Sample records for hypotension marked diuresis

  1. Effects of vasopressin administration on diuresis of water immersion in normal humans

    NASA Technical Reports Server (NTRS)

    Epstein, M.; Denunzio, A. G.; Loutzenhiser, R. D.

    1981-01-01

    The influence of vasopressin suppression on the diuresis encountered during water immersion is investigated in studies on normal humans immersed to the neck. Six hydrated male subjects were studied on two occasions while undergoing 6 h of immersion without or during the administration of aqueous vasopressin for the initial 4 h. Neck immersion is found to result in a significant increase in urinary flow rate beginning in the first hour and persisting throughout the immersion. The administration of vasopressin markedly attenuated the diuretic response throughout the period of infusion, while cessation of vasopressin administration during the final 2 h of immersion resulted in a marked offset of the antidiuresis. Results thus support the view that the suppression of antidiuretic hormone contributes to the immersion diuresis of hydrated subjects.

  2. Severe lithium intoxication treated by forced diuresis.

    PubMed Central

    Parfrey, P. S.; Ikeman, R.; Anglin, D.; Cole, C.

    1983-01-01

    In a woman who had been in coma for 4 days because of severe lithium intoxication forced diuresis led to full recovery. Forced diuresis is simpler than hemodialysis and may be as effective in some patients with severe lithium intoxication. PMID:6423251

  3. The non-diuretic hypotensive effects of thiazides are enhanced during volume depletion states

    PubMed Central

    Alshahrani, Saeed; Rapoport, Robert M.; Zahedi, Kamyar; Jiang, Min; Nieman, Michelle; Barone, Sharon; Meredith, Andrea L.; Lorenz, John N.; Rubinstein, Jack

    2017-01-01

    Thiazide derivatives including Hydrochlorothiazide (HCTZ) represent the most common treatment of mild to moderate hypertension. Thiazides initially enhance diuresis via inhibition of the kidney Na+-Cl- Cotransporter (NCC). However, chronic volume depletion and diuresis are minimal while lowered blood pressure (BP) is maintained on thiazides. Thus, a vasodilator action of thiazides is proposed, likely via Ca2+-activated K+ (BK) channels in vascular smooth muscles. This study ascertains the role of volume depletion induced by salt restriction or salt wasting in NCC KO mice on the non-diuretic hypotensive action of HCTZ. HCTZ (20mg/kg s.c.) lowered BP in 1) NCC KO on a salt restricted diet but not with normal diet; 2) in volume depleted but not in volume resuscitated pendrin/NCC dKO mice; the BP reduction occurs without any enhancement in salt excretion or reduction in cardiac output. HCTZ still lowered BP following treatment of NCC KO on salt restricted diet with paxilline (8 mg/kg, i.p.), a BK channel blocker, and in BK KO and BK/NCC dKO mice on salt restricted diet. In aortic rings from NCC KO mice on normal and low salt diet, HCTZ did not alter and minimally decreased maximal phenylephrine contraction, respectively, while contractile sensitivity remained unchanged. These results demonstrate 1) the non-diuretic hypotensive effects of thiazides are augmented with volume depletion and 2) that the BP reduction is likely the result of HCTZ inhibition of vasoconstriction through a pathway dependent on factors present in vivo, is unrelated to BK channel activation, and involves processes associated with intravascular volume depletion. PMID:28719636

  4. The incidence of urinary tract cancers is related to preserved diuresis: a single-center report.

    PubMed

    Premuzic, Vedran; Gamulin, Marija; Coric, Marijana; Jelakovic, Bojan

    2017-12-01

    Residual diuresis progressively decreases with longer dialysis vintage, and higher incidence of renal and urinary tract cancers was often observed in hemodialyzed patients compared to the general population so we hypothesized that patients without preserved residual diuresis have higher risk of renal and urinary tract cancers than patients with preserved residual diuresis. Retrospective clinical data and pathology reports were completed for 307 uremic patients undergoing chronic hemodialysis. Patients were divided into two subgroups regarding residual diuresis: the first group with residual diuresis < 500 mL, 133 of 173 (76.8%) patients from this group were completely anuric, and the second group with 134 patients with residual diuresis > 500 mL. Site- and type-specific cancers in our population of ESRD patients were all localized in estrogen-positive receptor organs. The increased risk of all types of urinary tract cancers occurred in the whole group, men and women, when compared to general population. There were a significantly higher number of patients with all types of cancers in the group with residual diuresis < 250 mL compared to patients with residual diuresis > 500 mL. Importantly, all urinary tract cancers were present in patients with residual diuresis < 500 mL. Higher incidence of urinary tract cancers found in ESRD patients undergoing chronic hemodialysis is associated with lost residual diuresis. Residual diuresis in these patients might be considered a risk marker for future urinary tract cancers as well as already established markers.

  5. Immersion diuresis without expected suppression of vasopressin

    NASA Technical Reports Server (NTRS)

    Keil, L. C.; Silver, J. E.; Wong, N.; Spaul, W. A.; Greenleaf, J. E.; Kravik, S. E.

    1984-01-01

    There is a shift of blood from the lower parts of the body to the thoracic circulation during bed rest, water immersion, and presumably during weightlessness. On earth, this central fluid shift is associated with a profound diuresis. However, the mechanism involved is not yet well understood. The present investigation is concerned with measurements regarding the plasma vasopressin, fluid, electrolyte, and plasma renin activity (PRA) responses in subjects with normal preimmersion plasma vasopressin (PVP) concentration. In the conducted experiments, PRA was suppressed significantly at 30 min of immersion and had declined by 74 percent by the end of the experiment. On the basis of previously obtained results, it appears that sodium excretion during immersion may be independent of aldosterone action. Experimental results indicate that PVP is not suppressed by water immersion in normally hydrated subjects and that other factors may be responsible for the diuresis.

  6. What Is Hypotension?

    MedlinePlus

    ... Hypotension Hypotension Also known as What Is Hypotension (HI-po-TEN-shun) is abnormally low blood pressure. ... this type of low blood pressure. Dehydration (de-hi-DRA-shun) is the most common cause of ...

  7. Osmotic diuresis-induced hypernatremia: better explained by solute-free water clearance or electrolyte-free water clearance?

    PubMed

    Popli, Subhash; Tzamaloukas, Antonios H; Ing, Todd S

    2014-01-01

    Hypernatremia may result from inadequate water intake, excessive water loss or a combination of the two. Osmotic diuresis leads to losses of both solute and water. The relationship between solute and water losses determines the resulting changes in serum osmolality and sodium concentration. Total solute loss is routinely higher than loss of water in osmotic diuresis. Theoretically, then, decreases in serum osmolality (and serum sodium concentration) should follow. In clinical situations of osmotic diuresis, however, reduction in osmolality can take place, but not reduction in serum sodium concentration. It is of note that serum sodium concentration changes are related to urinary losses of sodium and potassium but not to the loss of total solute. In osmotic diuresis, the combined loss of sodium and potassium per liter of urine is lower than the concurrent serum sodium level. Consequently, hypernatremia can ensue. A patient who presented with osmotic diuresis and hypernatremia is described here. In this patient, we have shown that electrolyte-free water clearance is a better index of the effect of osmotic diuresis on serum sodium concentration than the classic solute-free water clearance.

  8. Medial prefrontal cortex acetylcholine injection-induced hypotension: the role of hindlimb vasodilation

    NASA Technical Reports Server (NTRS)

    Crippa, G. E.; Lewis, S. J.; Johnson, A. K.; Correa, F. M.

    2000-01-01

    The injection of acetylcholine (ACh) into the cingulate region of the medial prefrontal cortex (MPFC) causes a marked fall in arterial blood pressure which is not accompanied by changes in heart rate. The purpose of the present study was to investigate the hemodynamic basis for this stimulus-induced hypotension in Sprague-Dawley rats. The study was designed to determine whether a change in the vascular resistance of hindlimb, renal or mesenteric vascular beds contributes to the fall in arterial pressure in response to ACh injection into the cingulate cortex. Miniature pulsed-Doppler flow probes were used to measure changes in regional blood flow and vascular resistance. The results indicated that the hypotensive response was largely due to a consistent and marked vasodilation in the hindlimb vascular bed. On this basis, an additional experiment was then undertaken to determine the mechanisms that contribute to hindlimb vasodilation. The effect of interrupting the autonomic innervation of one leg on the hindlimb vasodilator response was tested. Unilateral transection of the lumbar sympathetic chain attenuated the cingulate ACh-induced vasodilation in the ipsilateral, but not in the contralateral hindlimb. These results suggest that the hypotensive response to cingulate cortex-ACh injection is caused by skeletal muscle vasodilation mediated by a sympathetic chain-related vasodilator system.

  9. Response of the ECG to short-term diuresis in patients with heart failure.

    PubMed

    Madias, John E; Song, Jessica; White, C Michael; Kalus, James S; Kluger, Jeffrey

    2005-07-01

    Increase in the amplitude of electrocardiogram (ECG) QRS complexes has been observed in patients treated for heart failure (HF), but the underlying mechanism has not been delineated. Also, correlation of augmentation of the QRS potentials with loss of weight has been noted in patients recovering from anasarca of varying etiology, or after hemodialysis. We assessed the effect of diuresis-based fluid loss in patients treated for HF on the amplitude of ECG QRS complexes. This is a cohort study based on ECG and other data from a previously published investigation of patients with HF conducted at a university affiliated hospital, which used new measurements and analysis, performed by a totally blinded investigator based at another institution. Twenty-one patients (10 men) aged 70.5+/-12.7 years, 13 with ischemic, and 8 with nonischemic cardiomyopathy, were admitted to the hospital for management of exacerbated HF and were observed for 48 hours. The patients received diuresis, and had routine laboratory testing, documentation of the net fluid lost, and recording of ECGs prior to the initiation of therapy and at 24 and 48 hours. Percent change (%Delta) over the course of observation in the sums of the amplitude of QRS complexes from 12 leads (SigmaQRS12), 6-limb leads (SigmaQRS6), and leads 1+2 (SigmaQRS2) in mm of standard ECGs were correlated with net fluid loss corrected for admission weight in mL/kg. Fluid loss amounted to 3204.9+/-1399.5 mL in the course of 40+/-23 hours of diuresis. SigmaQRS12 was 160.9+/-42.3 mm before and 170.0+/-50.7 mm after diuresis (P=0. 024). Percent change in SigmaQRS12, SigmaQRS6, and SigmaQRS2 correlated well with the net fluid loss (r=-0.70, -0.82, -0.61, and P=0.002, 0.0005, 0.001) correspondingly. Changes in sums of the amplitude of QRS complexes of the standard ECG correlates well with net fluid loss in response to short-term diuresis in patients with HF. Change in the SigmaQRS12, SigmaQRS6, and SigmaQRS2 from ECGs before and after

  10. Thienoquinolins exert diuresis by strongly inhibiting UT-A urea transporters

    PubMed Central

    Ren, Huiwen; Wang, Yanhua; Xing, Yongning; Ran, Jianhua; Liu, Ming; Lei, Tianluo; Zhou, Hong; Li, Runtao; Sands, Jeff M.

    2014-01-01

    Urea transporters (UT) play an important role in the urine concentration mechanism by mediating intrarenal urea recycling, suggesting that UT inhibitors could have therapeutic use as a novel class of diuretic. Recently, we found a thienoquinolin UT inhibitor, PU-14, that exhibited diuretic activity. The purpose of this study was to identify more potent UT inhibitors that strongly inhibit UT-A isoforms in the inner medullary collecting duct (IMCD). Efficient thienoquinolin UT inhibitors were identified by structure-activity relationship analysis. Urea transport inhibition activity was assayed in perfused rat terminal IMCDs. Diuretic activity of the compound was determined in rats and mice using metabolic cages. The results show that the compound PU-48 exhibited potent UT-A inhibition activity. The inhibition was 69.5% with an IC50 of 0.32 μM. PU-48 significantly inhibited urea transport in perfused rat terminal IMCDs. PU-48 caused significant diuresis in UT-B null mice, which indicates that UT-A is the target of PU-48. The diuresis caused by PU-48 did not change blood Na+, K+, or Cl− levels or nonurea solute excretion in rats and mice. No toxicity was detected in cells or animals treated with PU-48. The results indicate that thienoquinolin UT inhibitors induce a diuresis by inhibiting UT-A in the IMCD. This suggests that they may have the potential to be developed as a novel class of diuretics with fewer side effects than classical diuretics. PMID:25298523

  11. Causes of chronic orthostatic hypotension

    NASA Technical Reports Server (NTRS)

    Robertson, D.; Robertson, R. M.

    1994-01-01

    OBJECTIVE: To determine the frequency of various causes of orthostatic hypotension. DESIGN: Survey. SETTING: Tertiary referral center. PATIENTS: One hundred patients with moderate to severe orthostatic hypotension. RESULTS: Twenty-seven percent of the patients had primary autonomic failure, 35% had secondary autonomic failure, and 38% had hypotension without evidence of generalized autonomic degeneration. CONCLUSIONS: In a tertiary referral center, only a minority of patients with severe orthostatic hypotension will have Shy-Drager syndrome or Bradbury-Eggleston syndrome as their primary disease. Occasional patients who initially appear to have Bradbury-Eggleston syndrome ultimately prove to have Shy-Drager syndrome or paraneoplastic autonomic failure. Antidepressant drugs, even in low doses, remain a major overlooked cause of orthostatic hypotension.

  12. Does training-induced orthostatic hypotension result from reduced carotid baroreflex responsiveness?

    NASA Technical Reports Server (NTRS)

    Pawelczyk, James A.; Raven, Peter B.

    1994-01-01

    As manned space travel has steadily increased in duration and sophistication, the answer to a simple, relevant question remains elusive. Does endurance exercise training - high intensity rhythmic activity, performed regularly for extended periods of time - alter the disposition to, or severity of, postflight orthostatic hypotension? Research results continue to provide different views; however, data are difficult to compare because of the following factors that vary between investigations: the type of orthostatic stress imposed (+Gz, lower body negative pressure (LBNP), head-up tilt); pretest perturbations used (exercise, heat exposure, head-down tilting, bed rest, water immersion, hypohydration, pharmacologically-induced diuresis); the length of the training program used in longitudinal investigations (days versus weeks versus months); the criteria used to define fitness; and the criteria used to define orthostatic tolerance. Generally, research results indicate that individuals engaged in aerobic exercise activities for a period of years have been reported to have reduced orthostatic tolerance compared to untrained control subjects, while the results of shorter term longitudinal studies remain equivocal. Such conclusions suggest that chronic athletic training programs reduce orthostatic tolerance, whereas relatively brief (days to weeks) training programs do not affect orthostatic tolerance to any significant degree (increase or decrease). A primary objective was established to identify the alterations in blood pressure control that contribute to training-induced orthostatic hypotension (TIOH). Although any aspect of blood pressure regulation is suspect, current research has been focused on the baroreceptor system. Reductions in carotid baroreflex responsiveness have been documented in exercise-trained rabbits, reportedly due to an inhibitory influence from cardiac afferent, presumably vagal, nerve fibers that is abolished with intrapericardiac denervation. The

  13. Crisis management during anaesthesia: hypotension.

    PubMed

    Morris, R W; Watterson, L M; Westhorpe, R N; Webb, R K

    2005-06-01

    Hypotension is commonly encountered in association with anaesthesia and surgery. Uncorrected and sustained it puts the brain, heart, kidneys, and the fetus in pregnancy at risk of permanent or even fatal damage. Its recognition and correction is time critical, especially in patients with pre-existing disease that compromises organ perfusion. To examine the role of a previously described core algorithm "COVER ABCD-A SWIFT CHECK", supplemented by a specific sub-algorithm for hypotension, in the management of hypotension when it occurs in association with anaesthesia. Reports of hypotension during anaesthesia were extracted and studied from the first 4000 incidents reported to the Australian Incident Monitoring Study (AIMS). The potential performance of the COVER ABCD algorithm and the sub-algorithm for hypotension was compared with the actual management as reported by the anaesthetist involved. There were 438 reports that mentioned hypotension, cardiovascular collapse, or cardiac arrest. In 17% of reports more than one cause was attributed and 550 causative events were identified overall. The most common causes identified were drugs (26%), regional anaesthesia (14%), and hypovolaemia (9%). Concomitant changes were reported in heart rate or rhythm in 39% and oxygen saturation or ventilation in 21% of reports. Cardiac arrest was documented in 25% of reports. As hypotension was frequently associated with abnormalities of other vital signs, it could not always be adequately addressed by a single algorithm. The sub-algorithm for hypotension is adequate when hypotension occurs in association with sinus tachycardia. However, when it occurs in association with bradycardia, non-sinus tachycardia, desaturation or signs of anaphylaxis or other problems, the sub-algorithm for hypotension recommends cross referencing to other relevant sub-algorithms. It was considered that, correctly applied, the core algorithm COVER ABCD would have diagnosed 18% of cases and led to resolution in

  14. Thienoquinolins exert diuresis by strongly inhibiting UT-A urea transporters.

    PubMed

    Ren, Huiwen; Wang, Yanhua; Xing, Yongning; Ran, Jianhua; Liu, Ming; Lei, Tianluo; Zhou, Hong; Li, Runtao; Sands, Jeff M; Yang, Baoxue

    2014-12-15

    Urea transporters (UT) play an important role in the urine concentration mechanism by mediating intrarenal urea recycling, suggesting that UT inhibitors could have therapeutic use as a novel class of diuretic. Recently, we found a thienoquinolin UT inhibitor, PU-14, that exhibited diuretic activity. The purpose of this study was to identify more potent UT inhibitors that strongly inhibit UT-A isoforms in the inner medullary collecting duct (IMCD). Efficient thienoquinolin UT inhibitors were identified by structure-activity relationship analysis. Urea transport inhibition activity was assayed in perfused rat terminal IMCDs. Diuretic activity of the compound was determined in rats and mice using metabolic cages. The results show that the compound PU-48 exhibited potent UT-A inhibition activity. The inhibition was 69.5% with an IC50 of 0.32 μM. PU-48 significantly inhibited urea transport in perfused rat terminal IMCDs. PU-48 caused significant diuresis in UT-B null mice, which indicates that UT-A is the target of PU-48. The diuresis caused by PU-48 did not change blood Na(+), K(+), or Cl(-) levels or nonurea solute excretion in rats and mice. No toxicity was detected in cells or animals treated with PU-48. The results indicate that thienoquinolin UT inhibitors induce a diuresis by inhibiting UT-A in the IMCD. This suggests that they may have the potential to be developed as a novel class of diuretics with fewer side effects than classical diuretics. Copyright © 2014 the American Physiological Society.

  15. A C-terminal Aldehyde Analog of the Insect Kinins Inhibits Diuresis in the Housefly

    DTIC Science & Technology

    2006-09-21

    p e p t i d e s 2 8 ( 2 0 0 7 ) 1 4 6 – 1 5 2A C-terminal aldehyde analog of the insect kinins inhibits diuresis in the housefly Ronald J. Nachman a...secretion in crickets, but shows inhibition of both in vitro and in vivo diuresis in the housefly . R-LK-CHO reduced the total amount of urine voided over 3 h...from flies injected with 1 mL of distilled water by almost 50%. The analog not only inhibits stimulation of housefly fluid secretion by the native

  16. Effects of maleic acid and uranyl on mercurial diuresis in dogs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nigrovic, V.; Koechel, D.A.; Cafruny, E.J.

    1973-01-01

    The effects of two nephrotoxic agents were studied in anesthetized dogs undergoing mercurial diuresis. One of the agents, uranyl, accumulates in the kidneys when administered as the acetate salt but does not readily react with sulfhydryl groups. In acute experiments uranyl acetate in doses up to 5 ..mu..mol/kg produced no change in the urinary excretion of sodium or chloride. Uranyl acetate given before the injection of mercury(II) did not reduce the diuretic response to inorganic mercury. The other compound, maleic acid, accumulates in the kidneys and also reacts readily with sulfhydryl groups. The administration of small doses of maleic acidmore » did not change the excretion of sodium but it decreased the excretion of chloride. The administration of maleic acid either before or after the administration of mercury completely abolished the diuretic response. The inhibition occurred without significant changes in urinary pH. Diuretic responses to ethacrynic acid, furosemide, hydrochlorothiazide or acetazolamide were preserved in maleate-treated dogs. Both the lack of any effect of uranyl on mercurial diuresis and the specific inhibition of mercurial diuresis by maleic acid support the presently accepted view that the renal diuretic receptor for mercury(II) has at least one sulfhydryl binding site. Although the inhibition is ascribed to competition between mercury(II) and maleate for binding on the receptor, it is conceivable that the reduction in urinary chloride excretion produced by maleate may be responsible, in part, for refractoriness to mercury(II).« less

  17. Evaluation of Polyuria: The Roles of Solute Loading and Water Diuresis.

    PubMed

    Bhasin, Bhavna; Velez, Juan Carlos Q

    2016-03-01

    Polyuria, defined as daily urine output in excess of 3.0 to 3.5L/d, can occur due to solute or water diuresis. Solute-induced polyuria can be seen in hospitalized patients after a high solute load from exogenous protein administration or following relief of urinary obstruction. Similar clinical scenarios are rarely encountered in the outpatient setting. We describe a case of polyuria due to high solute ingestion and excessive water intake leading to a mixed picture of solute and water diuresis. Restriction of the daily solute load and water intake resulted in complete resolution of polyuria. Determination of the daily excreted urinary osmoles may yield important clues to the cause of polyuria and should be included in the routine workup of polyuria. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  18. Treatment of Post-SCI Hypotension

    ClinicalTrials.gov

    2018-02-15

    Spinal Cord Injury; Autonomic Dysreflexia; Orthostatic Hypotension; Baroreceptor Integrity; Sympathetic Integrity; Vagal Integrity; Hypotension; Cerebral Blood Flow; Blood Pressure; Venous Occlusion Plethysmography

  19. Predictors of intraoperative hypotension and bradycardia.

    PubMed

    Cheung, Christopher C; Martyn, Alan; Campbell, Norman; Frost, Shaun; Gilbert, Kenneth; Michota, Franklin; Seal, Douglas; Ghali, William; Khan, Nadia A

    2015-05-01

    Perioperative hypotension and bradycardia in the surgical patient are associated with adverse outcomes, including stroke. We developed and evaluated a new preoperative risk model in predicting intraoperative hypotension or bradycardia in patients undergoing elective noncardiac surgery. Prospective data were collected in 193 patients undergoing elective, noncardiac surgery. Intraoperative hypotension was defined as systolic blood pressure <90 mm Hg for >5 minutes or a 35% decrease in the mean arterial blood pressure. Intraoperative bradycardia was defined as a heart rate of <60 beats/min for >5 minutes. A logistic regression model was developed for predicting intraoperative hypotension or bradycardia with bootstrap validation. Model performance was assessed using area under the receiver operating curves and Hosmer-Lemeshow tests. A total of 127 patients developed hypotension or bradycardia. The average age of participants was 67.6 ± 11.3 years, and 59.1% underwent major surgery. A final 5-item score was developed, including preoperative Heart rate (<60 beats/min), preoperative hypotension (<110/60 mm Hg), Elderly age (>65 years), preoperative renin-Angiotensin blockade (angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or beta-blockers), Revised cardiac risk index (≥3 points), and Type of surgery (major surgery), entitled the "HEART" score. The HEART score was moderately predictive of intraoperative bradycardia or hypotension (odds ratio, 2.51; 95% confidence interval, 1.79-3.53; C-statistic, 0.75). Maximum points on the HEART score were associated with an increased likelihood ratio for intraoperative bradycardia or hypotension (likelihood ratio, +3.64). The 5-point HEART score was predictive of intraoperative hypotension or bradycardia. These findings suggest a role for using the HEART score to better risk-stratify patients preoperatively and may help guide decisions on perioperative management of blood pressure and heart rate

  20. A pharmacokinetic/pharmacodynamic model capturing the time course of torasemide-induced diuresis in the dog.

    PubMed

    Paulin, A; Schneider, M; Dron, F; Woehrlé, F

    2016-12-01

    A pharmacokinetic/pharmacodynamic modelling approach was used to determine a dosage regimen which maximizes diuretic efficiency of torasemide in dogs. Kinetic profiles of plasma concentration, torasemide excretion rate in urine (TERU) and diuresis were investigated in 10 dogs after single oral administrations at 3 dose levels, 0.2, 0.8 and 1.6 mg/kg, and an intravenous injection of 0.2 mg/kg. Endogenous regulation was evidenced by a proteresis loop between TERU and diuresis. To describe the diuresis-time profile, TERU served as input into a turnover model with inhibition of loss of response, extended by a moderator acting on both loss and production of response. Estimated maximum inhibition of loss of response, I max , was 0.984 showing that torasemide is an efficacious diuretic able to suppress almost total water reabsorption. A TERU 50, value producing half of I max , of 1.45 μg/kg/h was estimated from the model. Pharmacokinetic and pharmacodynamic parameters were used to simulate the torasemide dose-effect relationship after oral administration. Model predictions were in good agreement with diuresis measured in a validation study conducted in 10 dogs, which were administered oral doses of 0.15, 0.4, 0.75, 1.5 and 4.5 mg/kg for 5 days. Finally, oral dose associated with the highest daily diuretic efficiency was predicted to be 0.1 mg/kg. © 2016 The Authors. Journal of Veterinary Pharmacology and Therapeutics Published by John Wiley & Sons Ltd.

  1. Effect of water temperature on diuresis-natriuresis: AVP, ANP, and urodilatin during immersion in men

    NASA Technical Reports Server (NTRS)

    Nakamitsu, S.; Sagawa, S.; Miki, K.; Wada, F.; Nagaya, K.; Keil, L. C.; Drummer, C.; Gerzer, R.; Greenleaf, J. E.; Hong, S. K.

    1994-01-01

    Effects of water temperature on diuresis, natriuresis, and associated endocrine responses during head-out immersion were studied in eight men during four 5-h experimental conditions: air control at 28 C and immersion at 34.5 C (thermoneutral (Tnt)), 36 C (above Tnt (aTnt)), and 32 C (below Tnt (bTnt). Esophageal temperature decreased by approximately 0.4 C in bTnt and increased by approximately 0.5 C in aTnt. Cardiac output increased by approximately 80% in aTnt and approximately 40% in bTnt while thoracic impedance, an index of central blood pooling, decreased by 7.5 ohms in bTnt (NS vs. Tnt) and 8.8 ohms in aTnt. Total peripheral resistance decreased at all temperatures (50% in aTnt, 20% in bTnt). Urine flow and Na(+) excretion increased by sixfold in bTnt and Tnt but by only threefold in aTnt. Creatinine clearance was unchanged while osmolal clearance (but not free water clearance) increased two-fold with all immersions. Plasma atrial natriuretic peptide (ANP), urinary urodilatin, and urinary guanosine 3',5'-cyclic monophosphate increased while plasma renin activity, aldosterone, and arginine vasopressin (AVP) decreased similarly at all temperatures. bTnt did not potentiate diuresis by selective attenuation of AVP. The overall natriuretic response exhibited a higher correlation with urodilatin than with ANP. Because diuresis and natriuresis were significantly attenuated in aTnt where central blood pooling was greater, we conclude that mechanisms other than the atrial stretch receptor reflex, i.e., urodilatin and effective arterial blood volume, may play more predominant roles in the mechanism of immersion-induced diuresis and natriuresis.

  2. Orthostatic hypotension-related hospitalizations in the United States.

    PubMed

    Shibao, Cyndya; Grijalva, Carlos G; Raj, Satish R; Biaggioni, Italo; Griffin, Marie R

    2007-11-01

    Orthostatic hypotension has been commonly described in elderly persons and is associated with an increased risk of falls, syncope, and cerebrovascular events. Nevertheless, the precise burden of this condition in the US is currently unknown. We analyzed discharge data from the Nationwide Inpatient Sample to identify orthostatic hypotension-related hospitalizations and associated comorbidities after excluding acute causes of this condition. National hospitalization rates were estimated using US census population estimates, and the medical conditions most frequently associated with orthostatic hypotension were assessed. In 2004, there were an estimated 80,095 orthostatic hypotension-related hospitalizations, yielding an overall rate of 36 (95% confidence interval, 34 to 38) hospitalizations per 100,000 US adults. Orthostatic hypotension was the primary diagnosis in 35% of these hospitalizations. The number of orthostatic hypotension-related hospitalizations increased steadily with age, and patients aged 75 years or older had the highest annual hospitalization rate, 233 per 100,000 (95% confidence interval, 217 to 249). The median length of hospital stay was 3 days (IQR 2-6) and the overall in-hospital mortality was 0.9%. Caucasian males were most likely to be hospitalized with orthostatic hypotension. Syncope was the most common comorbid condition reported among orthostatic hypotension patients. Orthostatic hypotension is a relatively common condition among hospitalized US elderly patients. In light of the progressive aging of the US population, the contribution of orthostatic hypotension to morbidity and mortality is likely to increase, and deserves further scrutiny.

  3. Forced diuresis with the RenalGuard system: impact on contrast induced acute kidney injury.

    PubMed

    Solomon, Richard

    2014-01-01

    Kidney injury following the administration of iodinated contrast media occurs particularly in patients with reduced kidney and cardiac function and when large doses of contrast are used. There is little compelling evidence that vasodilators and anti-oxidants prevent this injury. Most prevention trials have employed intravenous volume loading as a central strategy. However, the success of this approach depends upon maintaining euvolemia while producing a vigorous diuresis. A novel strategy for maintaining euvolemia and inducing a vigorous diuresis has been developed using the RenalGuard system. In this review; the mechanism of protective action is reviewed. The trials of the RenalGuard device are reviewed and future uses of the device are discussed. Copyright © 2013. Published by Elsevier Ltd.

  4. Ultrasonography-guided percutaneous nephrolithotomy with Chinese one-shot tract dilation technique based on stimulated diuresis: A report of 67 cases.

    PubMed

    Shi, Ying; Liang, Hua-Geng; Yang, Xiong; Hai, Bo; Wang, Liang; Xing, Yi-Fei; Ju, Wen; Zeng, Fu-Qing; Zhang, Xiao-Ping; Li, Wen-Cheng

    2016-12-01

    The safety and effectiveness of a novel Chinese one-shot dilation technique based on stimulated diuresis for percutaneous nephrolithotomy (PCNL) were investigated. After the feasibility of the Chinese one-shot dilation based on stimulated diuresis was verified by an animal study, this technique was applied in the clinical practice. A total of 67 patients in our department underwent the modified PCNL from July 2014 to June 2015. After the renal infundibulum was distended by stimulated diuresis, the kidney was punctured under the ultrasonographic guidance via the fornix of the target calyx. The working channel was dilated using a special designed pencil-shaped fascial dilator. The successful access rate, nephrostomy tract creation time, pre- and postoperative hemoglobin values and serum creatinine concentrations, stone-free rate and complications were recorded and analyzed. The renal infundibulum was successfully distended in all of the patients by the diuresis treatment. Under the ultrasonographic guidance, the successful access rate was 100% and the mean tract creation time was 2.0 min (range: 1.5-5.0 min). The stone-free rate right after surgery was 91.0%. Although the postoperative hemoglobin was significantly reduced (P<0.01), transfusion was not clinically necessary. There was no significant difference in serum creatinine concentrations before and after operation (P>0.05). No severe complication occurred during or after the PCNL. It was suggested that this Chinese one-shot dilation technique based on stimulated diuresis is an efficient and safe innovation for PCNL, and is even helpful for those patients with non-dilated pelvicaliceal systems.

  5. Perfusion index derived from a pulse oximeter can predict the incidence of hypotension during spinal anaesthesia for Caesarean delivery.

    PubMed

    Toyama, S; Kakumoto, M; Morioka, M; Matsuoka, K; Omatsu, H; Tagaito, Y; Numai, T; Shimoyama, M

    2013-08-01

    Hypotension during spinal anaesthesia for Caesarean delivery is a result of decreased vascular resistance due to sympathetic blockade and decreased cardiac output due to blood pooling in blocked areas of the body. Change in baseline peripheral vascular tone due to pregnancy may affect the degree of such hypotension. The perfusion index (PI) derived from a pulse oximeter has been used for assessing peripheral perfusion dynamics due to changes in peripheral vascular tone. The aim of this study was to examine whether baseline PI could predict the incidence of spinal anaesthesia-induced hypotension during Caesarean delivery. Parturients undergoing elective Caesarean delivery under spinal anaesthesia with hyperbaric bupivacaine 10 mg and fentanyl 20 μg were enrolled in this prospective study. The correlation between baseline PI and the degree of hypotension during spinal anaesthesia and also the predictability of spinal anaesthesia-induced hypotension during Caesarean delivery by PI were investigated. Baseline PI correlated with the degree of decreases in systolic and mean arterial pressure (r=0.664, P<0.0001 and r=0.491, P=0.0029, respectively). The cut-off PI value of 3.5 identified parturients at risk for spinal anaesthesia-induced hypotension with a sensitivity of 81% and a specificity of 86% (P<0.001). The change of PI in parturients with baseline PI ≤ 3.5 was not significant during the observational period, while PI in parturients with baseline PI>3.5 demonstrated marked decreases after spinal injection. We demonstrated that higher baseline PI was associated with profound hypotension and that baseline PI could predict the incidence of spinal anaesthesia-induced hypotension during Caesarean delivery.

  6. Orthostatic hypotension

    NASA Technical Reports Server (NTRS)

    Grimm, J. J.

    1980-01-01

    Following a brief physiopathological review, orthostatic hypotension is classified into three groups: organic, functional and medication-dependent. The importance of etiological diagnosis, the use of objective tests and appropriate therapy, especially concerning the organic forms, is stressed.

  7. Worsening Renal Function in Patients With Acute Heart Failure Undergoing Aggressive Diuresis Is Not Associated With Tubular Injury.

    PubMed

    Ahmad, Tariq; Jackson, Keyanna; Rao, Veena S; Tang, W H Wilson; Brisco-Bacik, Meredith A; Chen, Horng H; Felker, G Michael; Hernandez, Adrian F; O'Connor, Christopher M; Sabbisetti, Venkata S; Bonventre, Joseph V; Wilson, F Perry; Coca, Steven G; Testani, Jeffrey M

    2018-05-08

    Worsening renal function (WRF) in the setting of aggressive diuresis for acute heart failure treatment may reflect renal tubular injury or simply indicate a hemodynamic or functional change in glomerular filtration. Well-validated tubular injury biomarkers, N -acetyl-β-d-glucosaminidase, neutrophil gelatinase-associated lipocalin, and kidney injury molecule 1, are now available that can quantify the degree of renal tubular injury. The ROSE-AHF trial (Renal Optimization Strategies Evaluation-Acute Heart Failure) provides an experimental platform for the study of mechanisms of WRF during aggressive diuresis for acute heart failure because the ROSE-AHF protocol dictated high-dose loop diuretic therapy in all patients. We sought to determine whether tubular injury biomarkers are associated with WRF in the setting of aggressive diuresis and its association with prognosis. Patients in the multicenter ROSE-AHF trial with baseline and 72-hour urine tubular injury biomarkers were analyzed (n=283). WRF was defined as a ≥20% decrease in glomerular filtration rate estimated with cystatin C. Consistent with protocol-driven aggressive dosing of loop diuretics, participants received a median 560 mg IV furosemide equivalents (interquartile range, 300-815 mg), which induced a urine output of 8425 mL (interquartile range, 6341-10 528 mL) over the 72-hour intervention period. Levels of N -acetyl-β-d-glucosaminidase and kidney injury molecule 1 did not change with aggressive diuresis (both P >0.59), whereas levels of neutrophil gelatinase-associated lipocalin decreased slightly (-8.7 ng/mg; interquartile range, -169 to 35 ng/mg; P <0.001). WRF occurred in 21.2% of the population and was not associated with an increase in any marker of renal tubular injury: neutrophil gelatinase-associated lipocalin ( P =0.21), N -acetyl-β-d-glucosaminidase ( P =0.46), or kidney injury molecule 1 ( P =0.22). Increases in neutrophil gelatinase-associated lipocalin, N -acetyl

  8. Droxidopa for Symptomatic Neurogenic Hypotension.

    PubMed

    Ferguson-Myrthil, Nadia

    Droxidopa is a first-in-class, orally available, synthetic amino acid precursor of norepinephrine that received accelerated Food and Drug Administration approval in February 2014 after Orphan Drug status for a debilitating condition known as symptomatic neurogenic orthostatic hypotension. Neurogenic disorders often lead to postural hypotension as a result of poor norepinephrine release from its storage sites. Clinical data suggest increases in standing systolic blood pressure and improvements in many other markers for subjective relief in patients with symptomatic neurogenic hypotension who received droxidopa therapy over 1-2 weeks. Studies evaluating the sustained effects of droxidopa are ongoing. With minimal drug interactions (even with carbidopa use) or adverse effects, droxidopa therapy can be used safely in patients with a variety of neurologic conditions; however, more data are needed to determine its appropriate pharmacotherapeutic role. In all, droxidopa is a safe and effective medication for the treatment of orthostatic dizziness/lightheadedness, or the "feeling that you are about to black out" in adult patients with symptomatic neurogenic orthostatic hypotension secondary to primary autonomic failure (Parkinson's disease, multiple system atrophy, and pure autonomic failure), dopamine beta-hydroxylase deficiency, and nondiabetic autonomic neuropathy.

  9. Sympathoinhibition and hypotension in carotid sinus hypersensitivity

    NASA Technical Reports Server (NTRS)

    Smith, M. L.; Ellenbogen, K. A.; Eckberg, D. L.

    1992-01-01

    Carotid sinus reflex hypersensitivity is a known cause of syncope in humans. The condition is characterized by cardioinhibition and vasodepression, each to varying degrees. The extent and importance of sympathoinhibition has not been determined in patients with carotid sinus hypersensitivity. This study reports on the extent of sympathoinhibition measured directly directly during carotid massage with and without atrioventricular sequential pacing, in a patient with symptomatic carotid sinus reflex hypersensitivity. Carotid massage elicited asystole, hypotension and complete inhibition of muscle sympathetic nerve activity. Carotid massage during atrioventricular pacing produced similar sympathoinhibition, but with minimal hypotension. Therefore, sympathoinhibition did not contribute importantly to the hypotension during carotid massage in the supine position in this patient. Further investigations are required to elucidate the relation of sympathoinhibition to hypotension in patients with carotid sinus hypersensitivity in the upright position.

  10. Value of diuresis renography in the post-natal period of assumed physiological renal immaturity.

    PubMed

    Eising, E G; Bonzel, K E; Zander, C; Farahati, J; Reiners, C

    1997-11-01

    The aim of this study was to determine if it is possible to exclude renal obstruction using diuresis renography in the first 6 weeks of life (the period of physiological renal immaturity), thus avoiding unnecessary invasive procedures, such as the Whitaker test or surgery. Diuresis renography with 123I-hippuran was performed in 27 patients aged less than 6 weeks and in 50 older children who acted as a reference group (age 6 weeks to 1 year, n = 28; age 1-10 years, n = 22). All 27 patients had significant dilatation of the pelvicalyceal system on ultrasonography. Renal curves were evaluated by mathematical curve characteristics (split renal function, counts, T-max, etc.) as the visual grade of obstruction. Whole-kidney regions of interest were defined on images summed over 30 min; renal parenchyma on images summed over 5 min. The renal curves of 18/27 patients indicated tracer accumulation and led to frusemide administration. Only two patients showed no significant response to frusemide and had to be further investigated by the Whitaker test. The frequency of kidneys with no response to frusemide revealed no significant differences in the three groups. Whole-kidney evaluation resulted in an overestimation of obstruction in 9/150 kidneys, which matches the lower correlation to the DMSA separation values for this method of evaluation. In contrast with the literature, significant post-renal obstruction can be excluded by diuresis renography in most cases in spite of renal immaturity and can help to avoid invasive procedures.

  11. How do pediatric anesthesiologists define intraoperative hypotension?

    PubMed

    Nafiu, Olubukola O; Voepel-Lewis, Terri; Morris, Michelle; Chimbira, Wilson T; Malviya, Shobha; Reynolds, Paul I; Tremper, Kevin K

    2009-11-01

    Although blood pressure (BP) monitoring is a recommended standard of care by the ASA, and pediatric anesthesiologists routinely monitor the BP of their patients and when appropriate treat deviations from 'normal', there is no robust definition of hypotension in any of the pediatric anesthesia texts or journals. Consequently, what constitutes hypotension in pediatric anesthesia is currently unknown. We designed a questionnaire-based survey of pediatric anesthesiologists to determine the BP ranges and thresholds used to define intraoperative hypotension (IOH). Members of the Society of Pediatric Anesthesia (SPA) and the Association of Paediatric Anaesthetists (APA) of Great Britain and Ireland were contacted through e-mail to participate in this survey. We asked a few demographic questions and five questions about specific definitions of hypotension for different age groups of patients undergoing inguinal herniorraphy, a common pediatric surgical procedure. The overall response rate was 56% (483/860), of which 76% were SPA members. Majority of the respondents (72%) work in academic institutions, while 8.9% work in institutions with fewer than 1000 annual pediatric surgical caseload. About 76% of respondents indicated that a 20-30% reduction in baseline systolic blood pressure (SBP) indicates significant hypotension in children under anesthesia. Most responders (86.7%) indicated that they use mean arterial pressure or SBP (72%) to define IOH. The mean SBP values for hypotension quoted by SPA members was about 5-7% lower across all pediatric age groups compared to values quoted by APA members (P = 0.001 for all age groups). There is great variability in the BP parameters used and the threshold used for defining and treating IOH among pediatric anesthesiologists. The majority of respondents considered a 20-30% reduction from baseline in SBP as indicative of significant hypotension. Lack of a consensus definition for a common clinical condition like IOH could have

  12. Respective contributions of α-adrenergic and non-adrenergic mechanisms in the hypotensive effect of imidazoline-like drugs

    PubMed Central

    Bruban, Véronique; Feldman, Josiane; Greney, Hugues; Dontenwill, Monique; Schann, Stephan; Jarry, Christian; Payard, Marc; Boutin, Jean; Scalbert, Elizabeth; Pfeiffer, Bruno; Renard, Pierre; Vanhoutte, Paul; Bousquet, Pascal

    2001-01-01

    The hypotensive effect of imidazoline-like drugs, such as clonidine, was first attributed to the exclusive stimulation of central α2-adrenoceptors (α2ARs). However, a body of evidence suggests that non-adrenergic mechanisms may also account for this hypotension. This work aims (i) to check whether imidazoline-like drugs with no α2-adrenergic agonist activity may alter blood pressure (BP) and (ii) to seek a possible interaction between such a drug and an α2ARs agonist α-methylnoradrenaline (α-MNA). We selected S23515 and S23757, two imidazoline-like drugs with negligible affinities and activities at α2ARs but with high affinities for non-adrenergic imidazoline binding sites (IBS). S23515 decreased BP dose-dependently (−27±5% maximal effect) when administered intracisternally (i.c.) to anaesthetized rabbits. The hypotension induced by S23515 (100 μg kg−1 i.c.) was prevented by S23757 (1 mg kg−1 i.c.) and efaroxan (10 μg kg−1 i.c.), while these compounds, devoid of haemodynamic action by themselves, did not alter the hypotensive effect of α-MNA (3 and 30 μg kg−1 i.c.). Moreover, the α2ARs antagonist rauwolscine (3 μg kg−1 i.c.) did not prevent the effect of S23515. Finally, whilst 3 μg kg−1 of S23515 or 0.5 μg kg−1 of α-MNA had weak hypotensive effects, the sequential i.c. administration of these two drugs induced a marked hypotension (−23±2%). These results indicate that an imidazoline-like drug with no α2-adrenergic properties lowers BP and interacts synergistically with an α2ARs agonist. PMID:11350862

  13. Postprandial hypotension in older survivors of critical illness.

    PubMed

    Nguyen, Thu Anh Ngoc; Ali Abdelhamid, Yasmine; Weinel, Luke M; Hatzinikolas, Seva; Kar, Palash; Summers, Matthew J; Phillips, Liza K; Horowitz, Michael; Jones, Karen L; Deane, Adam M

    2018-06-01

    In older people postprandial hypotension occurs frequently; and is an independent risk factor for falls, cardiovascular events, stroke and death. The primary aim of this pilot study was to estimate the frequency of postprandial hypotension and evaluate the mechanisms underlying this condition in older survivors of an Intensive Care Unit (ICU). Thirty-five older (>65 years) survivors were studied 3 months after discharge. After an overnight fast, participants consumed a 300 mL drink containing 75 g glucose, labelled with 20 MBq 99m Tc-calcium phytate. Patients had concurrent measurements of blood pressure, heart rate, blood glucose and gastric emptying following drink ingestion. Proportion of participants is presented as percent (95% CI) and continuous variables as mean (SD). Postprandial hypotension was evident in 10 (29%; 95% CI 14-44), orthostatic hypotension in 2 (6%; 95% CI 0-13) and cardiovascular autonomic dysfunction in 2 (6%; 95% CI 0-13) participants. The maximal postprandial nadir for systolic blood pressure and diastolic blood pressures were -29 (14) mmHg and -18 (7) mmHg. In this cohort of older survivors of ICU postprandial hypotension occurred frequently . This suggests that postprandial hypotension is an unrecognised issue in older ICU survivors. Copyright © 2018. Published by Elsevier Inc.

  14. Orthostatic hypotension: epidemiology, pathophysiology and management

    NASA Technical Reports Server (NTRS)

    Jacob, G.; Robertson, D.

    1995-01-01

    Orthostatic hypotension is characterized by low upright blood pressure levels and symptoms of cerebral hypoperfusion. Whereas orthostatic hypotension is heterogeneous, correct pathophysiologic diagnosis is important because of therapeutic and prognostic considerations. Although therapy is not usually curative, it can be extraordinarily beneficial if it is individually tailored. Management of the Shy-Drager syndrome (multiple-system atrophy) remains a formidable challenge.

  15. Cognitive performance in hypotensive persons with spinal cord injury.

    PubMed

    Jegede, Adejoke B; Rosado-Rivera, Dwindally; Bauman, William A; Cardozo, Christopher P; Sano, Mary; Moyer, Jeremy M; Brooks, Monifa; Wecht, Jill Maria

    2010-02-01

    Due to sympathetic de-centralization, individuals with spinal cord injury (SCI), especially those with tetraplegia, often present with hypotension, worsened with upright posture. Several investigations in the non-SCI population have noted a relationship between chronic hypotension and deficits in memory, attention and processing speed and delayed reaction times. To determine cognitive function in persons with SCI who were normotensive or hypotensive over a 24-h observation period while maintaining their routine activities. Subjects included 20 individuals with chronic SCI (2-39 years), 13 with tetraplegia (C4-8) and 7 with paraplegia (T2-11). Individuals with hypotension were defined as having a mean 24-h systolic blood pressure (SBP) below 110 mmHg for males and 100 mmHg for females, and having spent >or=50% of the total time below these gender-specific thresholds. The cognitive battery used included assessment of memory (CVLT), attention and processing speed (Digit Span, Stroop word and color and Oral Trails A), language (COWAT) and executive function (Oral Trails B and Stroop color-word). Demographic parameters did not differ among the hypotensive and normotensive groups; the proportion of individuals with tetraplegia (82%) was higher in the hypotensive group. Memory was significantly impaired (P < 0.05) and there was a trend toward slowed attention and processing speed (P < 0.06) in the hypotensive compared to the normotensive group. These preliminary data suggest that chronic hypotension in persons with SCI is associated with deficits in memory and possibly attention and processing speed, as previously reported in the non-SCI population.

  16. Orthostatic hypotension predicts motor decline in early Parkinson disease.

    PubMed

    Kotagal, Vikas; Lineback, Christina; Bohnen, Nicolaas I; Albin, Roger L

    2016-11-01

    Orthostatic hypotension is increasingly reported as a risk factor for development of late-stage disease features in Parkinson disease (PD). Less is known about its significance in individuals with early PD who are often targeted for neuroprotective trials. Using data from the CALM-PD trial (n = 275), we explored whether early orthostatic hypotension predicts a decline in the Unified Parkinson's Disease Rating Scale (UPDRS) II (activities of daily living) or UDPRS III (motor) score after 102 weeks. We also explored risk factors for worsening orthostatic hypotension over a nearly 2-year period. After controlling for age, disease duration, gender, study drug, change in mini-mental status exam score, levodopa equivalent dose, and baseline UPDRS II or III score respectively, the degree of orthostatic hypotension at enrollment associated with a worsening in UPDRS motor score (t = 2.40, p = 0.017) at week 102 but not with UPDRS ADL score (t = 0.83, p = 0.409). Worsening in orthostatic hypotension during the study associated with longer disease duration (t = 2.37, p = 0.019) and lower body mass index (BMI) (t = -2.96, p = 0.003). Baseline orthostatic hypotension is a predictor of UPDRS motor decline in individuals with early PD and should be accounted for in clinical trial design. Low BMI may predict orthostatic hypotension in PD. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Antagonistic effects of atipamezole, yohimbine, and prazosin on xylazine-induced diuresis in clinically normal cats

    PubMed Central

    Murahata, Yusuke; Miki, Yuya; Hikasa, Yoshiaki

    2014-01-01

    This study aimed to investigate and compare the antagonistic effects of atipamezole, yohimbine, and prazosin on xylazine-induced diuresis in clinically normal cats. Five cats were repeatedly used in each of the 9 groups. One group was not medicated. Cats in the other groups received 2 mg/kg BW xylazine intramuscularly, and saline (as the control); 160 μg/kg BW prazosin; or 40, 160, or 480 μg/kg BW atipamezole or yohimbine intravenously 0.5 h later. Urine and blood samples were collected 10 times over 8 h. Urine volume, pH, and specific gravity; plasma arginine vasopressin (AVP) concentration; and creatinine, osmolality, and electrolyte values in both urine and plasma were measured. Both atipamezole and yohimbine antagonized xylazine-induced diuresis, but prazosin did not. The antidiuretic effect of atipamezole was more potent than that of yohimbine but not dose-dependent, in contrast to the effect of yohimbine at the tested doses. Both atipamezole and yohimbine reversed xylazine-induced decreases in both urine specific gravity and osmolality, and the increase in free water clearance. Glomerular filtration rate, osmolar clearance, and plasma electrolyte concentrations were not significantly altered. Antidiuresis of either atipamezole or yohimbine was not related to the area under the curve for AVP concentration, although the highest dose of both atipamezole and yohimbine increased plasma AVP concentration initially and temporarily, suggesting that this may in part influence antidiuretic effects of both agents. The diuretic effect of xylazine in cats may be mediated by α2-adrenoceptors but not α1-adrenoceptors. Atipamezole and yohimbine can be used as antagonistic agents against xylazine-induced diuresis in clinically normal cats. PMID:25356000

  18. Hypotension following patent ductus arteriosus ligation: the role of adrenal hormones.

    PubMed

    Clyman, Ronald I; Wickremasinghe, Andrea; Merritt, T Allen; Solomon, Tabitha; McNamara, Patrick; Jain, Amish; Singh, Jaideep; Chu, Alison; Noori, Shahab; Sekar, Krishnamurthy; Lavoie, Pascal M; Attridge, Joshua T; Swanson, Jonathan R; Gillam-Krakauer, Maria; Reese, Jeff; DeMauro, Sara; Poindexter, Brenda; Aucott, Sue; Satpute, Monique; Fernandez, Erika; Auchus, Richard J

    2014-06-01

    To test the hypothesis that an impaired adrenal response to stress might play a role in the hypotension that follows patent ductus arteriosus (PDA) ligation. We performed a multicenter study of infants born at <32 weeks' gestation who were about to undergo PDA ligation. Serum adrenal steroids were measured 3 times: before and after a cosyntropin (1.0 μg/kg) stimulation test (performed before the ligation), and at 10-12 hours after the ligation. A standardized approach for diagnosis and treatment of postoperative hypotension was followed at each site. A modified inotrope score (1 × dopamine [μg/kg/min] + 1 × dobutamine) was used to monitor the catecholamine support an infant received. Infants were considered to have catecholamine-resistant hypotension if their greatest inotrope score was >15. Of 95 infants enrolled, 43 (45%) developed hypotension and 14 (15%) developed catecholamine-resistant hypotension. Low postoperative cortisol levels were not associated with the overall incidence of hypotension after ligation. However, low cortisol levels were associated with the refractoriness of the hypotension to catecholamine treatment. In a multivariate analysis: the OR for developing catecholamine-resistant hypotension was OR 36.6, 95% CI 2.8-476, P = .006. Low cortisol levels (in infants with catecholamine-resistant hypotension) were not attributable to adrenal immaturity or impairment; their cortisol precursor concentrations were either low or unchanged, and their response to cosyntropin was similar to infants without catecholamine-resistant hypotension. Infants with low cortisol concentrations after PDA ligation are likely to develop postoperative catecholamine-resistant hypotension. We speculate that decreased adrenal stimulation, rather than an impaired adrenal response to stimulation, may account for the decreased production. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Hypotension following patent ductus arteriosus ligation: the role of adrenal hormones

    PubMed Central

    Clyman, Ronald I.; Wickremasinghe, Andrea; Merritt, T. Allen; Solomon, Tabitha; McNamara, Patrick; Jain, Amish; Singh, Jaideep; Chu, Alison; Noori, Shahab; Sekar, Krishnamurthy; Lavoie, Pascal M.; Attridge, Joshua T.; Swanson, Jonathan R.; Gillam-Krakauer, Maria; Reese, Jeff; DeMauro, Sara; Poindexter, Brenda; Aucott, Sue; Satpute, Monique; Fernandez, Erika; Auchus, Richard J.

    2014-01-01

    Objective To test the hypothesis that an impaired adrenal response to stress might play a role in the hypotension that follows patent ductus arteriosus (PDA) ligation. Study design We performed a multicenter study of infants born at <32 weeks gestation who were about to undergo PDA ligation. Serum adrenal steroids were measured three times: before and after a cosyntropin (1.0 microgram/kg) stimulation test (performed prior to the ligation), and at 10–12 hours after the ligation. A standardized approach for diagnosis and treatment of postoperative hypotension was followed at each site. A modified Inotrope Score (1 x dopamine (μg/kg/min) + 1 x dobutamine) was used to monitor the catecholamine support an infant received. Infants were considered to have catecholamine-resistant hypotension if their highest Inotrope Score was >15. Results Of 95 infants enrolled, 43 (45%) developed hypotension and 14 (15%) developed catecholamine-resistant hypotension. Low post-operative cortisol levels were not associated with the overall incidence of hypotension following ligation. However, low cortisol levels were associated with the refractoriness of the hypotension to catecholamine treatment. In a multivariate analysis: the odds ratio for developing catecholamine-resistant hypotension was OR=36.6, CI=2.8–476, p=0.006. Low cortisol levels (in infants with catecholamine-resistant hypotension) were not due to adrenal immaturity or impairment; their cortisol precursor concentrations were either low or unchanged and their response to cosyntropin was similar to infants without catecholamine-resistant hypotension. Conclusion Infants with low cortisol concentrations following PDA ligation are likely to develop postoperative catecholamine-resistant hypotension. We speculate that decreased adrenal stimulation, rather than an impaired adrenal response to stimulation, may account for the decreased production. PMID:24636853

  20. Postural hypotension and the anti-gravity suit.

    PubMed

    Brook, W H

    1994-10-01

    An air force anti-gravity suit, as used by fighter pilots to prevent loss of consciousness, has been successfully employed to treat severe postural hypotension in a patient with Shy-Drager syndrome. The definition of postural hypotension is reviewed, and reference is made to the previous use of the anti-gravity suit in the treatment of this condition.

  1. Autonomic Cardiovascular Control and Executive Function in Chronic Hypotension.

    PubMed

    Duschek, Stefan; Hoffmann, Alexandra; Reyes Del Paso, Gustavo A; Ettinger, Ulrich

    2017-06-01

    Chronic low blood pressure (hypotension) is characterized by complaints such as fatigue, reduced drive, dizziness, and cold limbs. Additionally, deficits in attention and memory have been observed. Autonomic dysregulation is considered to be involved in the origin of this condition. The study explored autonomic cardiovascular control in the context of higher cognitive processing (executive function) in hypotension. Hemodynamic recordings were performed in 40 hypotensive and 40 normotensive participants during execution of four classical executive function tasks (number-letter task, n-back task, continuous performance test, and flanker task). Parameters of cardiac sympathetic control, i.e., stroke volume, cardiac output, pre-ejection period, total peripheral resistance, and parasympathetic control, i.e., respiratory sinus arrhythmia and baroreflex sensitivity, were obtained. The hypotensive group exhibited lower stroke volume and cardiac output, as well as higher pre-ejection period and baroreflex sensitivity during task execution. Increased error rates in hypotensive individuals were observed in the n-back and flanker tasks. In the total sample, there were positive correlations of error rates with pre-ejection period, baroreflex sensitivity and respiratory sinus arrhythmia, and negative correlations with cardiac output. Group differences in stroke volume, cardiac output, and pre-ejection period suggest diminished beta-adrenergic myocardial drive during executive function processing in hypotension, in addition to increased baroreflex function. Although further research is warranted to quantify the extent of executive function impairment in hypotension, the results from correlation analysis add evidence to the notion that higher sympathetic inotropic influences and reduced parasympathetic cardiac influences are accompanied by better cognitive performance.

  2. Low Blood Pressure (Hypotension)

    MedlinePlus

    ... Low blood pressure on standing up (orthostatic, or postural, hypotension). This is a sudden drop in blood ... progressive damage to the autonomic nervous system, which controls involuntary functions such as blood pressure, heart rate, ...

  3. Continuous recording of excretory water loss from Musca domestica using a flow-through humidity meter: hormonal control of diuresis.

    PubMed

    Coast, Geoffrey M

    2004-05-01

    Water loss from adult male houseflies was continuously recorded using a flow-through humidity meter, which enabled losses to be apportioned between the sum of cuticular and respiratory transpiration, salivation and excretion. Transpiration accounted for >95% of water lost from sham-injected flies, compared with excretion (3.0%) and salivation (2.4%). In contrast, excretion accounted for 40% of water lost from flies injected with > or =3 microl of saline, whereas salivary losses were unchanged. Saline injections (1-5 microl) expanded the abdomen in the dorsal-ventral plane, and this expansion was positively correlated with the magnitude of the ensuing diuresis, suggesting the signal for diuretic hormone release originates from stretch receptors in abdominal tergal-sternal muscles. The effects of decapitation, severing the ventral nerve cord within the neck or ligaturing the neck, showed the head was needed to initiate and maintain diuresis, but was neither the source of diuretic hormone nor did it control the discharge of urine from the anus. These findings indicate the head is part of the neural-endocrine pathway between abdominal stretch receptors and sites for diuretic hormone release from the thoracic-abdominal ganglion mass. Evidence is presented for Musdo-K having a hormonal role in the control of diuresis, although other neuropeptides may also be implicated.

  4. A marked decrease in bispectral index with elevation of suppression ratio by cervical haematoma reducing cerebral perfusion pressure.

    PubMed

    Umegaki, N; Hirota, K; Kitayama, M; Yatsu, Y; Ishihara, H; Mtasuki, A

    2003-11-01

    A 77-year-old man with a ruptured abdominal aortic aneurysm undergoing aneurysmectomy were anaesthetised with ketamine under bispectral index (BIS) monitoring, which is a clinical EEG monitor for measurement of depth of anaesthesia/sedation. First marked BIS reduction with elevation of suppression ratio (SR) was observed following severe hypotension by deflation of the aortic occlusion balloon. The re-inflation and rapid blood transfusion improved haemodyanamics and BIS and SR. At second marked BIS reduction with SR elevation, a heavy cervical swelling due to a massive subcutaneous haematoma around the previously mis-punctured right carotid artery extending throughout the whole neck was observed without hypotension. Cervical relief incision improved the BIS and SR. The present case suggests that BIS monitor may be a simple and convenient monitor for cerebral ischaemia detection.

  5. Orthostatic hypotension acutely impairs executive functions in Parkinson's disease.

    PubMed

    Sforza, Michela; Assogna, Francesca; Rinaldi, Domiziana; Sette, Giuliano; Tagliente, Stefania; Pontieri, Francesco E

    2018-04-07

    Orthostatic hypotension is a frequent non-motor symptom of Parkinson's disease, with negative prognostic role on cognitive functions. Here we measured the acute effects of orthostatic hypotension on executive functions in Parkinson's disease patients devoid of hypertension, carotid artery stenosis, and significant chronic cerebrovascular pathology. Measurements were carried out during regular visits in outpatient setting. Twenty-eight Parkinson's disease patients were recruited and studied along scheduled outpatient visits. They were divided into two groups (n = 14 each) based on the presence or lack of orthostatic hypotension. This was diagnosed according to international guidelines. All patients were submitted to the Stroop's test and to the phonological and semantic verbal fluency test after 10-min resting in supine position and immediately upon standing in upright position. Testing lasted less than 5 min in either position. In upright position, subjects with orthostatic hypotension displayed significantly worse performances at the Stroop's test word reading time (22.1 ± 4.1 vs. 14.9 ± 4.0 s), interference time (56.1 ± 12.3 vs. 41.4 ± 11.8 s), and number of errors at the interference section (5.8 ± 3.2 vs. 1.3 ± 2.1) as compared to those without orthostatic hypotension. These results demonstrate that worsening of attentive function upon standing can be measured in Parkinson's disease patients with orthostatic hypotension during routine outpatient visits. These findings suggest that clinically asymptomatic orthostatic hypotension in Parkinson's disease patients may acutely worsen neuropsychological performances with possible negative impact on daily functioning.

  6. Audiovestibular impairments associated with intracranial hypotension.

    PubMed

    Choi, Jae-Hwan; Cho, Kee-Yong; Cha, Seung-Yi; Seo, Jae-Deuk; Kim, Min-Ji; Choi, Yu Ri; Kim, Sung-Hee; Kim, Ji-Soo; Choi, Kwang-Dong

    2015-10-15

    To investigate the patterns and mechanisms of audiovestibular impairments associated with intracranial hypotension. We had consecutively recruited 16 patients with intracranial hypotension at the Neurology Center of Pusan National University Hospital for two years. Spontaneous, gaze-evoked, and positional nystagmus were recorded using 3D video-oculography in all patients, and the majority of them also had pure tone audiometry and bithermal caloric tests. Of the 16 patients, five (31.3%) reported neuro-otological symptoms along with the orthostatic headache while laboratory evaluation demonstrated audiovestibular impairments in ten (62.5%). Oculographic analyses documented spontaneous and/or positional nystagmus in six patients (37.5%) including weak spontaneous vertical nystagmus with positional modulation (n=4) and pure positional nystagmus (n=2). One patient presented with recurrent spontaneous vertigo and tinnitus mimicking Meniere's disease, and showed unidirectional horizontal and torsional nystagmus with normal head impulse tests during the attacks. Bithermal caloric tests were normal in all nine patients tested. Audiometry showed unilateral (n=6) or bilateral (n=1) sensorineural hearing loss in seven (53.8%) of the 13 patients tested. Intracranial hypotension frequently induces audiovestibular impairments. In addition to endolymphatic hydrops and irritation of the vestibulocochlear nerve, compression or traction of the brainstem or cerebellum due to loss of CSF buoyancy may be considered as a mechanism of frequent spontaneous or positional vertical nystagmus in patients with intracranial hypotension. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Identification of Hypotensive Emergency Department Patients with Cardiogenic Etiologies.

    PubMed

    Henning, Daniel J; Kearney, Kathleen E; Hall, Michael Kennedy; Mahr, Claudius; Shapiro, Nathan I; Nichol, Graham

    2018-02-01

    Identify predictors of cardiogenic etiology among emergency department (ED) patients with hypotension, and use these predictors to create a clinical tool to discern cardiogenic etiology of hypotension. This secondary analysis evaluated a prospective cohort of consecutive patients with hypotension in an urban, academic, tertiary care ED from November 2012 to September 2013. We included adults with hypotension, defined as a new vasopressor requirement, systolic blood pressure (SBP) < 90 mm Hg after at least 1 L of crystalloid or 2 units packed red blood cells, or SBP < 90 mm Hg and fluids withheld due to concern for fluid overload. The primary outcome was cardiogenic etiology, adjudicated by two physician chart review, with 25% paired chart review (kappa = 0.92). We used multivariable logistic regression to predict cardiogenic etiology, utilizing clinical data abstracted from the electronic medical record. We created a prediction score from significant covariates and calculated its test characteristics for cardiogenic hypotension. Of 700 patients with hypotension, 107 (15.3%, 95% CI: 12.6%-18.0%) had cardiogenic etiology. Independent predictors of cardiogenic etiology were shortness of breath (OR 4.1, 95% CI: 2.5-6.7), troponin > 0.1 ng/mL (37.5, 7.1-198.2), electrocardiographic ischemia (8.9, 4.0-19.8), history of heart failure (2.0, 1.1-3.3), and absence of fever (4.5, 2.3-8.7) (area under the curve [AUC] = 0.83). The prediction score created from these predictors yielded 78% sensitivity and 77% specificity for cardiogenic etiology (AUC = 0.827). Clinical predictors offer reasonable ED screening sensitivity for cardiogenic hypotension, while demonstrating sufficient specificity to facilitate early cardiac interventions.

  8. High-volume forced diuresis with matched hydration using the RenalGuard System to prevent contrast-induced nephropathy: A meta-analysis of randomized trials.

    PubMed

    Shah, Rahman; Wood, Sarah J; Khan, Sajjad A; Chaudhry, Amina; Rehan Khan, M; Morsy, Mohamed S

    2017-12-01

    Contrast-induced nephropathy (CIN) is a well-recognized complication of coronary angiography that is associated with poor outcomes. Several small randomized controlled trials (RCTs) have recently shown that in patients with chronic kidney disease (CKD), furosemide-induced forced diuresis with matched hydration using the RenalGuard system can prevent its occurrence. However, individual studies have been underpowered and thus cannot show significant differences in major clinical endpoints. Forced diuresis with matched hydration using the RenalGuard system improves clinical outcomes in patients undergoing coronary angiography. Scientific databases and websites were searched for relevant RCTs. The pooled risk ratios were calculated using random-effects models. The primary endpoint was CIN, and the secondary endpoints were major adverse clinical events (MACEs) and the need for renal replacement therapy. Data from 3 trials including 586 patients were analyzed. High-volume forced diuresis with matched hydration using the RenalGuard system decreased risk of CIN by 60% (risk ratio: 0.40, 95% confidence interval: 0.25 to 0.65, P < 0.001), MACE rate by 59%, and the need for renal replacement therapy by 78%, compared with the standard of care. In patients with CKD undergoing coronary angiography, high-volume forced diuresis with matched hydration using the RenalGuard system significantly reduces the risk of CIN, MACE rate, and the need for renal replacement therapy. Larger RCTs with sufficient power are needed to confirm these findings. © 2017 Wiley Periodicals, Inc.

  9. Histamine-releasing properties of Polysorbate 80 in vitro and in vivo: correlation with its hypotensive action in the dog.

    PubMed

    Masini, E; Planchenault, J; Pezziardi, F; Gautier, P; Gagnol, J P

    1985-09-01

    The solvent of commercial amiodarone (Polysorbate 80) has been reported to produce haemodynamic responses in humans and in dogs similar to those produced by histamine infusion. We therefore evaluated the correlation between hypotension induced by the solvent of amiodarone and its histamine-releasing properties in the awake dog. The solvent of amiodarone administered to a dog, over 5 min in a dose of 10 mg/kg of Polysorbate 80, produced severe hypotension after the first administration; the second injection (24 h later) caused fewer hypotensive effects. Histamine release in the peripheral tissues was demonstrated by a marked increase in plasma histamine concentrations, with the maximum value 10 min after the solvent administration. H1- and H2-receptor blockade with mepyramine (5 mg/kg) and cimetidine (10 mg/kg) significantly reduced the cardiovascular effects of the solvent. Isolated peritoneal mast cells from rats also released histamine in response to Polysorbate 80. These studies show that Polysorbate 80 releases histamine both in vitro and in isolated mast cells from rats and in vivo in the dog, and that the plasma concentrations are correlated with the haemodynamic responses.

  10. A centrally mediated prolonged hypotension produced by oxotremorine or pilocarpine

    PubMed Central

    Dage, R.C.

    1979-01-01

    1 Oxotremorine, methyloxotremorine, pilocarpine or arecoline were given intravenously to anaesthetized cats, dogs or rats, and intraperitoneally to conscious normotensive and spontaneously hypertensive rats, pretreated with doses of methylatropine that completely blocked peripheral muscarinic receptors, to ascertain their effects on blood pressure and heart rate. 2 Oxotremorine but not methyloxotremorine produced a prolonged hypotension in cats and dogs but not in rats. Heart rate was not changed. Pilocarpine, although less potent, produced an identical effect, whereas the effect of arecoline was short by comparison. The hypotensive effect of these drugs was reversed by atropine. 3 In dogs, oxotremorine produced a prolonged hypotension with no change in heart rate or cardiac output. 4 A decrease in spontaneous sympathetic nerve activity accompanied the hypotension in cats. Both effects were reversed by atropine but could be reinvoked by large doses of oxotremorine. 5 The oxotremorine-induced hypotension in cats was not altered by decerebration but was abolished by high cervical spinal section. 6 The results indicate that the prolonged hypotension elicited by oxotremorine is mediated by an action at muscarinic receptors in the brain stem resulting in a decrease in sympathetic nerve activity and peripheral resistance but not heart rate or cardiac output. PMID:760887

  11. Response by the corpuscles of Stannius to hypotensive stimuli in three divergent ray-finned fishes (Amia calva, Anguilla rostrata, and Catastomus commersoni): cardiovascular and morphological changes.

    PubMed

    Butler, D G; Zhang, D H; Villadiego, R; Oudit, G Y; Youson, J H; Cadinouche, M Z A

    2003-06-15

    In accordance with their vital role in cardiovascular physiology () corpuscles of Stannius (CS) from two teleosts and an holostean species showed marked and consistent degranulation and exocytotic responses to hypotensive stimuli. In eels (Anguilla rostrata LeSueur) acute blood withdrawal (hypovolemic hypotension) was followed by a prompt decrease in cardiac output (CO) and dorsal aortic pressure (P(DA)), a compensatory tachycardic response and an increase in systemic vascular resistance (R(SYS)). Isovolemic hypotension induced by papaverine i.v., led to a similar, but more prolonged, decrease in P(DA) but the heart rate (HR) continued to accelerate, thereby counterbalancing the severe and persistent decrease in R(SYS). Both hypovolemic and isovolemic hypotension were followed by a significant depletion of cytoplasmic granules from eel CS even though plasma concentrations of Ca, Mg, Na(+), and K(+) were normal. In an ancient holostean fish, the bowfin, Amia calva and a generalized teleost fish, Catastomus commersoni, the number of cytoplasmic granules decreased by 39% and 54%, respectively, 120 min after the acute withdrawal of 8 ml kg bw(-1) of blood. These findings suggest that a primary role of the CS is to release cytoplasmic granules containing renin or isorenin into the blood circulation, in response to hypotension and/or hypovolemia.

  12. Prevalence of hypotension and its association with cognitive function among older adults.

    PubMed

    Momtaz, Yadollah Abolfathi; Hamid, Tengku Aizan; Haron, Sharifah Azizah; Bagat, Mohamad Fazdillah; Mohammadi, Fatemeh

    2018-04-01

    The negative effect of hypertension has overshadowed possible health problems associated with hypotension. The purposes of this study were to describe the prevalence of hypotension in older adults and to determine the association between hypotension and cognitive function, after adjusting for possible covariates. The data for the study consisting of 1067 community-dwelling older adults were obtained from a national survey entitled "Identifying Psychosocial and Identifying Economic Risk Factor of Cognitive Impairment among Elderly", conducted in Malaysia. The hypotension was considered as blood pressure <120/75 mm Hg, measuring by standard mercury manometer. Data analysis was performed using the SPSS Version 22.0. The mean age of the respondents was 68.27 (SD = 5.93). Mean score of cognitive function as measured by MMSE was 22.70 (SD = 4.95). The prevalence of hypotension was 29.3%. The prevalence of cognitive impairment for hypotension group was 25.6%. Results of multiple linear regression analysis revealed that hypotension is negatively associated with cognitive function (Beta = -0.11, p<.01), after adjusting for age, gender, education, marital status, employment status, diabetes, heart disease, stroke and gastritis. The study showing hypotension is significantly associated with decreased cognitive function in later life, implies more attention to low blood pressure in old age.

  13. Neurocirculatory abnormalities in Parkinson disease with orthostatic hypotension: independence from levodopa treatment.

    PubMed

    Goldstein, David S; Eldadah, Basil A; Holmes, Courtney; Pechnik, Sandra; Moak, Jeffrey; Saleem, Ahmed; Sharabi, Yehonatan

    2005-12-01

    Patients with Parkinson disease often have orthostatic hypotension. Neurocirculatory abnormalities underlying orthostatic hypotension might reflect levodopa treatment. Sixty-six Parkinson disease patients (36 with orthostatic hypotension, 15 off and 21 on levodopa; 30 without orthostatic hypotension) had tests of reflexive cardiovagal gain (decrease in interbeat interval per unit decrease in systolic pressure during the Valsalva maneuver; orthostatic increase in heart rate per unit decrease in pressure); reflexive sympathoneural function (decrease in pressure during the Valsalva maneuver; orthostatic increment in plasma norepinephrine); and cardiac and extracardiac noradrenergic innervation (septal myocardial 6-[18F]fluorodopamine-derived radioactivity; supine plasma norepinephrine). Severity of orthostatic hypotension did not differ between the levodopa-untreated and levodopa-treated groups with Parkinson disease and orthostatic hypotension (-52+/-6 [SEM] versus -49+/-5 mm Hg systolic). The 2 groups had similarly low reflexive cardiovagal gain (0.84+/-0.23 versus 1.33+/-0.35 ms/mm Hg during Valsalva; 0.43+/-0.09 versus 0.27+/-0.06 bpm/mm Hg during orthostasis); and had similarly attenuated reflexive sympathoneural responses (97+/-29 versus 71+/-23 pg/mL during orthostasis; -82+/-10 versus -73+/-8 mm Hg during Valsalva). In patients off levodopa, plasma norepinephrine was lower in those with (193+/-19 pg/mL) than without (348+/-46 pg/mL) orthostatic hypotension. Low values for reflexive cardiovagal gain, sympathoneural responses, and noradrenergic innervation were strongly related to orthostatic hypotension. Parkinson disease with orthostatic hypotension features reflexive cardiovagal and sympathoneural failure and cardiac and partial extracardiac sympathetic denervation, independent of levodopa treatment.

  14. The principles and technical aspects of diuresis renography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Conway, J.J.

    1989-12-01

    It is intuitive that dilation of the urinary tract is most likely caused by obstruction. However, the opposite is more often true. That is, dilation is not associated with obstruction, especially in children. The most common causes for hydronephrosis and hydroureter include infection, vesicoureteral reflux, congenital megacalyces and megaureter, previous obstruction, and bladder noncompliance. Theoretically, one can consider obstruction on the basis of its significance, which is that there may be a loss of renal function with time. Techniques such as intravenous pyelography and ultrasonography, which anatomically document the degree of dilation of the urinary tract, cannot quantitatively determine themore » presence of obstruction or its significance. Radionuclide renography more readily quantifies abnormal renal function. Serial renographic studies with furosemide can document renal function loss and, thus, determine the significance of the obstruction. Diuresis renography with furosemide provides an objective quantitative means for determining the renal function changes over time.« less

  15. Midodrine as a Countermeasure for Post-Spaceflight Orthostatic Hypotension

    NASA Technical Reports Server (NTRS)

    Stenger, Michael B.; Stein, Sydney P.; Meck, Janice V.; Platts, Steven H.

    2008-01-01

    One possible mechanism for post-spaceflight orthostatic hypotension, which affects approximately 30% of astronauts after short duration shuttle missions, is inadequate norepinephrine release during upright posture. We performed a two phased study to determine the effectiveness of an alpha1-adrenergic agonist, midodrine, as a countermeasure to post-spaceflight orthostatic hypotension. The first phase of the study examined the landing day orthostatic responses of six veteran astronauts after oral midodrine (10 mg) administered on the ground within approximately two hours of wheel stop. One female crewmember exhibited orthostatic hypotension in a previous flight but not after midodrine. Five male crewmembers, who did not exhibit orthostatic hypotension during previous flights, also did not show signs of orthostatic hypotension after midodrine. Additionally, phase one showed that midodrine did not cause hypertension in these crewmembers. In the second phase of this study, midodrine is ingested inflight (near time of ignition, TIG) and orthostatic responses are determined immediately upon landing via an 80 degree head-up tilt test performed on the crew transport vehicle (CTV). Four of ten crewmembers have completed phase two of this study. Two crewmembers completed the landing day tilt tests, while two tests were ended early due to presyncopal symptoms. All subjects had decreased landing day stroke volumes and increased heart rates compared to preflight. Midodrine appears to have increased total peripheral resistance in one crewmember who was able to complete the landing day tilt test. The effectiveness of midodrine as a countermeasure to immediate post-spaceflight orthostatic hypotension has yet to be determined; interpretation is made more difficult due to low subject number and the lack of control subjects on the CTV.

  16. Genetics and molecular biology of hypotension

    NASA Technical Reports Server (NTRS)

    Robertson, D.

    1994-01-01

    Major strides in the molecular biology of essential hypertension are currently underway. This has tended to obscure the fact that a number of inherited disorders associated with low blood pressure exist and that these diseases may have milder and underrecognized phenotypes that contribute importantly to blood pressure variation in the general population. This review highlights some of the gene products that, if abnormal, could cause hypotension in some individuals. Diseases due to abnormalities in the catecholamine enzymes are discussed in detail. It is likely that genetic abnormalities with hypotensive phenotypes will be as interesting and diverse as those that give rise to hypertensive disorders.

  17. The Association Between Mild Intraoperative Hypotension and Stroke in General Surgery Patients.

    PubMed

    Hsieh, Jason K; Dalton, Jarrod E; Yang, Dongsheng; Farag, Ehab S; Sessler, Daniel I; Kurz, Andrea M

    2016-10-01

    Intraoperative hypotension may contribute to perioperative strokes. We therefore tested the hypothesis that intraoperative hypotension is associated with perioperative stroke. After institutional review board approval for this case-control study, we identified patients who had nonneurological, noncardiac, and noncarotid surgery under general anesthesia at the Cleveland Clinic between 2005 and 2011 and experienced a postoperative stroke. Control patients not experiencing postoperative stroke were matched in a 4-to-1 ratio using propensity scores and restriction to the same procedure type as stroke patients. The association between intraoperative hypotension, measured as time-integrated area under a mean arterial pressure (MAP) of 70 mm Hg, and postoperative stroke was assessed using zero-inflated negative binomial regression. Among 106 337 patients meeting inclusion criteria, we identified 120 who had confirmed postoperative stroke events based on manual chart review. Four-to-one propensity matching yielded a final matched sample of 104 stroke cases and 398 controls. There was no association between stroke and intraoperative hypotension. Stroke patients were not more likely than controls to have been hypotensive (odds ratio, 0.49 [0.18-1.38]), and among patients with intraoperative hypotension, stroke patients did not experience a greater degree of hypotension than controls (ratio of geometric means, 1.07 [0.76-1.53]). In our propensity score-matched case-control study, we did not find an association between intraoperative hypotension, defined as MAP < 70 mm Hg, and postoperative stroke.

  18. Orthostatic hypotension

    NASA Technical Reports Server (NTRS)

    Ninet, J.

    1981-01-01

    Basic orientation of the article, by the leader of a group of medical researchers associated with hospitals in Lyon, France, is toward definition and classification. A table divides OH (orthostatic hypotension) according to physiopathological classification into sympathicotonic and asympathicotonic types and then each of these into primary and secondary with subdivisions. The figure sketches organization and functioning of the baroreflex arc. Applications to clinical study of circulatory reflexes, listing measurement tests and the biological study of hormonal regulation listing the appropriate kinds of studies. Data are not given.

  19. Orthostatic hypotension in patients, bed rest subjects, and astronauts

    NASA Technical Reports Server (NTRS)

    Lathers, C. M.; Charles, J. B.

    1994-01-01

    Orthostatic hypotension after even short space flights has affected a significant number of astronauts. Given the need for astronauts to function at a high level of efficiency during and after their return from space, the application of pharmacologic and other treatments is strongly indicated. This report addresses the clinical problem of orthostatic hypotension and its treatments to ascertain whether pharmacologic or physiologic treatment may be useful in the prevention of orthostatic hypotension associated with space flight. Treatment of orthostatic hypotension in patients now includes increasing intravascular volume with high sodium intake and mineralocorticoids, or increasing vascular resistance through the use of drugs to stimulate alpha or block beta vascular receptors. Earlier treatment used oral sympathomimetic ephedrine hydrochloride alone or with "head-up" bed rest. Then long-acting adrenocortical steroid desoxycorticosterone preparations with high-salt diets were used to expand volume. Fludrocortisone was shown to prevent the orthostatic drop in blood pressure. The combination of the sympathomimetic amine hydroxyamphetamine and a monoamine oxidase inhibitor tranylcypromine has been used, as has indomethacin alone. Davies et al. used mineralocorticoids at low doses concomitantly with alpha-agonists to increase vasoconstrictor action. Schirger et al used tranylcypromine and methylphenidate with or without a Jobst elastic leotard garment or the alpha-adrenergic agonist midodrine (which stimulates both arterial and venous systems without direct central nervous system or cardiac effects). Vernikos et al established that the combination of fludrocortisone, dextroamphetamine, and atropine exhibited a beneficial effect on orthostatic hypotension induced by 7-day 6 degrees head-down bed rest (a model used to simulate the weightlessness of space flight). Thus, there are numerous drugs that, in combination with mechanical techniques, including lower body negative

  20. Nimodipine-induced hypotension but not nitroglycerin-induced hypotension preserves long- and short-term memory in adult mice.

    PubMed

    Haile, Michael; Galoyan, Samuel; Li, Yong-Sheng; Cohen, Barry H; Quartermain, David; Blanck, Thomas; Bekker, Alex

    2012-05-01

    Acute hypotension may be implicated in cognitive dysfunction. L-type calcium channel blockers in the setting of hypoxia are protective of learning and memory. We tested the hypothesis that hypotension induced by nimodipine (NIMO) and nicardipine (NICA) would be protective of long- and short-term memory compared to hypotension induced by nitroglycerin (NTG). Forty Swiss-Webster mice (30 to 35 g, 6 to 8 weeks) were randomized into 4 groups for i.p. injection immediately after passive avoidance (PA) learning on day 0: (1) NTG (30 mg/kg); (2) NICA (40 mg/kg); (3) NIMO (40 mg/kg); and (4) saline. PA training latencies (seconds) were recorded for entry from a suspended platform into a Plexiglas tube where a shock (0.3 mA; 2-second duration) was automatically delivered. On day 2 latencies were recorded during a testing trial during which no shock was delivered. Latencies >900 seconds were assigned this value. Lower testing latency is indicative of an impairment of long-term associative memory. Forty-nine additional mice were randomized into similar groups for object recognition testing (ORT) and given i.p. injections on day 0. ORT measures short-term memory by exploiting the tendency of mice to prefer novel objects where a familiar object is present. On day 5 during training, 2 identical objects were placed in a circular arena and mice explored both for 15 minutes. A testing trial was conducted 1 hour later for 3 minutes after a novel object replaced a familiar one. Mice with intact memory spend about 65% of the time exploring the novel object. Mice with impaired memory devote equal time to each object. Recognition index (RI) is defined as the ratio of time spent exploring the novel object to time spent exploring both objects was the measure of memory. Mean arterial blood pressure (MAP), cerebral bloodflow, and body and brain oxygenation (PO(2)) studies were done in separate groups of mice to determine the dosages for matched degrees of hypotension and the physiological

  1. [Predictors of physical incapacity degree to chronic hemodialysis patients in Kinshasa : Key role of the residual diuresis].

    PubMed

    Mokoli, Vieux Momeme; Bukabau, Justine Busanga; Izeidi, Patrick Parmba Osa; Luse, Jeanine Losa; Mukendi, Stéphane Kalambay; Mashinda, Désiré Kulimba; Makulo, Jean Robert Rissassy; Sumaili, Ernest Kiswaya; Lepira, François Bompeka; Nseka, Nazaire Mangani

    2016-12-01

    Identifying predictors of physical incapacity degree in patients on chronic hemodialysis in Kinshasa. Bicentric analytical study, between January 2007 and July 2013. Degree of physical handicap was evaluated at 6months of hemodialysis based on the scale of Rosser. Logistic regression sought the predictors of no or light physical incapacity (Rosser<3) vs. moderate to maximum (Rosser≥3). P was set at 0.05. One hundred twenty-seven patients (127) patients received at least 6months of hemodialysis (53.3±11years; 73.2 % male), 79 (62.2 %) had no or light incapacity and 48 (37.8 %) moderate to maximum. Predictors of lower physical incapacity in univaried analysis were: secured funding, high socioeconomic level, lack of diabetes mellitus, high body weight, normal systolic and diastolic blood pressure, residual diuresis 3months later, hemoglobin and hematocrit, low comorbidity, arteriovenous fistula, erythropoietin, at least 12hours of hemodialysis per week and lack of intradialytic complications. After logistic regression, a high residual diuresis 3months of hemodialysis has proved an independent predictor of lower physical Incapacity (aOR 0.998; P=0.024) next to the lack of diabetes mellitus (aOR 0.239; P=0.024), good control of systolic (aOR 0.958; P=0.013) and diastolic (aOR 1.089; P=0.003) blood pressure and the use of erythropoietin (aOR 5.687; P=0.004). Preserving residual diuresis is associated with lower physical incapacity and must be integrated in the management in hemodialysis. Copyright © 2016 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.

  2. Effects of hypotensive anesthesia on blood transfusion rates in craniosynostosis corrections.

    PubMed

    Fearon, Jeffrey A; Cook, T Kevin; Herbert, Morley

    2014-05-01

    Hypotensive anesthesia is routinely used during craniosynostosis corrections to reduce blood loss. Noting that cerebral oxygenation levels often fell below recommended levels, the authors sought to measure the effects of hypotensive versus standard anesthesia on blood transfusion rates. One hundred children undergoing craniosynostosis corrections were randomized prospectively into two groups: a target mean arterial pressure of either 50 mm Hg or 60 mm Hg. Aside from anesthesiologists, caregivers were blinded and strict transfusion criteria were followed. Multiple variables were analyzed, and appropriate statistical testing was performed. The hypotensive and standard groups appeared similar, with no statistically significant differences in mean age (46.5 months versus 46.5 months), weight (19.25 kg versus 19.49 kg), procedure [anterior remodeling (34 versus 31) versus posterior (19 versus 16)], or preoperative hemoglobin level (13 g/dl versus 12.9 g/dl). Intraoperative mean arterial pressures differed significantly (56 mm Hg versus 66 mm Hg; p < 0.001). The captured cell saver amount was lower in the hypotensive group (163 cc versus 204 cc; p = 0.02), yet no significant differences were noted in postoperative hemoglobin levels (8.8 g/dl versus 9.3 g/dl). Fifteen of 100 patients (15 percent) received allogenic transfusions, but no statistically significant differences were noted in transfusion rates between the hypotensive [nine of 53 (17.0 percent)] and standard anesthesia [six of 47 (13 percent)] group (p = 0.056). No significant difference in transfusion requirements was found between hypotensive and standard anesthesia during craniosynostosis corrections. Considering potential benefits of improved cerebral blood flow and total body perfusion, surgeons might consider performing craniosynostosis corrections without hypotension. Therapeutic, II.

  3. OSMOTIC DIURESIS AND ITS EFFECT ON TOTAL ELECTROLYTE DISTRIBUTION IN PLASMA AND URINE OF THE AGLOMERULAR TELEOST, LOPHIUS AMERICANUS

    PubMed Central

    Forster, Roy P.; Berglund, Fredrik

    1956-01-01

    Quantitative evaluations have been made of the chief anions and cations in plasma, urine, and pericardial fluid taken both from freshly captured goosefish and from those undergoing "laboratory diuresis." Measurements included: Na, K, Ca, Mg, Cl, SO4, PO4, protein, HCO3, NH3, pH, titratable acidity, freezing point depression, creatine, trimethylamine oxide, and plasma volume. The total patterns of electrolyte distribution in these body fluids are presented. The morphologically undifferentiated aglomerular tubule acts as a barrier to the free diffusion of monovalent electrolytes, while transporting actively the divalent ions, especially Mg. Urine taken from freshly captured fish is hypotonic to plasma, low in electrolyte, and as much as 50 per cent of its total osmolarity is accounted for by nitrogenous components. Of these creatine is transported most actively by the renal tubule cells. With the onset of diuresis immediately after capture, plasma osmolarity slowly rises and urine suddenly becomes isotonic with plasma as chloride floods into the urine. The active movement of Mg continues during diuresis and urine/plasma concentration ratios of 100 or more are sustained for days while the animals are kept in the laboratory. Na follows chloride and never reaches 50 per cent of plasma values, and K never appears in urine in more than mere traces. Electrolytes in this system are viewed as not being in true equilibrium but rather as constituting a biological steady state with the distribution across renal cells being maintained against passive diffusion by the expenditure of cellular energy. PMID:13286453

  4. Interaction of mianserin and some hypotensive drugs in Wistar rats.

    PubMed

    Górska, Dorota; Andrzejczak, Dariusz

    2004-01-01

    Mianserin is thought to exert little effect on the cardiovascular system. In fact its safety in comparison with tricyclic drugs is high. Various experiments gave varying results as for the influence of the drug on arterial blood pressure in people and animals. Therefore, a study was undertaken in Wistar rats to evaluate interactions of mianserin administered intraperitoneally as a single dose, and for 21 days with 3 hypotensive drugs showing different mechanism of action (propranolol, enalapril, prazosine). The systolic, diastolic and mean blood pressure was measured with a LETICA apparatus. The results of the study revealed that administration of mianserin in normotensive rats leads to a short-term decrease in blood pressure and significantly enhanced the hypotensive effect of prazosine. Repeated doses of mianserin lead to a temporary increase in blood pressure after 2 weeks of administration. Single and repeated administration of mianserin did not change the hypotensive effect of propranolol and enalapril. Three-week therapy with mianserin significantly enhanced the hypotensive effect of prazosine.

  5. Point-of-care ultrasound leads to diagnostic shifts in patients with undifferentiated hypotension.

    PubMed

    Shokoohi, Hamid; Boniface, Keith S; Zaragoza, Michelle; Pourmand, Ali; Earls, James P

    2017-12-01

    To assess the impact of an ultrasound hypotension protocol in identifying life-threatening diagnoses that were missed in the initial evaluation of patients with hypotension and shock. A subset of cases from a previously published prospective study of hypotensive patients who presented at the Emergency Department in a single, academic tertiary care hospital is described. An ultrasound-trained emergency physician performed an ultrasound on each patient using a standardized hypotension protocol. In each case, the differential diagnosis and management plan was solicited from the treating physician immediately before and after the ultrasound. This is a case series of patients with missed diagnoses in whom ultrasound led to a dramatic shift in diagnosis and management by detecting life threatening pathologies. Following a published prospective study of the effect on an ultrasound protocol in 118 hypotensive patients, we identified a series of cases that ultrasound protocol unexpectedly determined serious life threatening diagnoses such as Takotsubo cardiomyopathy, pulmonary embolism, pericardial effusion with tamponade physiology, abdominal aortic aneurysm and perforated viscus resulting in proper diagnoses and management. These hypotensive patients had completely unsuspected but critical diagnoses explaining their hypotension, who in every case had their management altered to target the newly identified life-threatening condition. A hypotension protocol is an optimal use of ultrasound that exemplifies "right time, right place", and impacts decision-making at the bedside. In cases with undifferentiated hypotension, ultrasound is often the most readily available option to ensure that the most immediate life-threatening conditions are quickly identified and addressed in the order of their risk potential. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Midodrine as a Countermeasure for Post-spaceflight Orthostatic Hypotension

    NASA Technical Reports Server (NTRS)

    Platts, Steven H.; Ziegler, Michael G.; Waters, Wendy W.; Meck, Janice V.

    2007-01-01

    Up to 30 % of astronauts exhibit post-spaceflight orthostatic hypotension due to inadequate norepinephrine release during upright posture following short duration spaceflight. We hypothesize that the (alpha)1-adrenergic agonist midodrine will be an effective countermeasure. This study is being conducted in 2 phases. The first phase is complete and consisted testing six short duration crew members. All of these subjects participated in preflight and postflight tilt testing on a control flight as well as on the test flights, where midodrine was administered after landing, 1 hour before testing. Hemodynamic variables were compared between the 2 flights. Midodrine improved stroke volume, cardiac output, systolic pressure and heart rate, without increasing vascular resistance. None of these subjects experienced orthostatic hypotension on landing day. Phase II is similar to phase I, except that midodrine is ingested in flight (near TIG) and the tilt test is performed immediately after landing on the CTV. One crewmember has completed phase II testing. This crewmember had no evidence of orthostatic hypotension or presyncope, four additional crewmembers have volunteered for this study. To date, midodrine has been shown to be a safe and effective countermeasure to post-spaceflight orthostatic hypotension.

  7. Clinical application of diadenosine tetraphosphate (Ap4A:F-1500) for controlled hypotension.

    PubMed

    Kikuta, Y; Ohiwa, E; Okada, K; Watanabe, A; Haruki, S

    1999-01-01

    In our animal study, it was revealed that diadenosine tetraphosphate (Ap4A:F-1500) has a dose-dependent hypotension effect of up to 60% decrease in mean arterial pressure compared to control value. Furthermore, in healthy male volunteers, the safety of Ap4A up to 4 mg.min-1 was confirmed. In patients who require surgical procedures under general anesthesia together with controlled hypotension, hypotension was induced by Ap4A in order to examine its hypotensive effect and modulating action on the blood pressure. Ten patients who required controlled hypotension and who were scheduled for elective surgery under general anesthesia were studied. Anesthesia was maintained with isoflurane (n = 7) or sevoflurane (n = 3) in oxygen-nitrous oxide. Controlled hypotension was induced by Ap4A administered at a rate of 10-20 micrograms.kg-1.min-1. The dose was adjusted at a maximum rate of 80 micrograms.kg-1.min-1 until the target blood pressure was achieved. Arterial blood pressure and heart rate were monitored. Arterial samples were drawn at 4 separate time points to measure the concentration of Ap4A in the plasma. The time required for attaining the target blood pressure after initiation of Ap4A infusion was about 16 min, and the time lapse between withdrawal of infusion to recovery of blood pressure was about 18 min. No reflex tachycardia was observed during infusion of Ap4A and no rebound hypertension was evident after withdrawal. The plasma Ap4A concentration increased in response to the acceleration rate of Ap4A administration with a tendency of augmented hypotensive effect. As it produces an excellent hypotensive effect together with a modulating action on blood pressure, Ap4A was assessed as useful in producing controlled hypotension.

  8. Low-Volume Intense Exercise Elicits Post-exercise Hypotension and Subsequent Hypervolemia, Irrespective of Which Limbs Are Exercised.

    PubMed

    Graham, Matthew J; Lucas, Samuel J E; Francois, Monique E; Stavrianeas, Stasinos; Parr, Evelyn B; Thomas, Kate N; Cotter, James D

    2016-01-01

    Exercise reduces arterial and central venous blood pressures during recovery, which contributes to its valuable anti-hypertensive effects and to facilitating hypervolemia. Repeated sprint exercise potently improves metabolic function, but its cardiovascular effects (esp. hematological) are less well-characterized, as are effects of exercising upper versus lower limbs. The purposes of this study were to identify the acute (<24 h) profiles of arterial blood pressure and blood volume for (i) sprint intervals versus endurance exercise, and (ii) sprint intervals using arms versus legs. Twelve untrained males completed three cycling exercise trials; 50-min endurance (legs), and 5(*)30-s intervals using legs or arms, in randomized and counterbalanced sequence, at a standardized time of day with at least 8 days between trials. Arterial pressure, hemoglobin concentration and hematocrit were measured before, during and across 22 h after exercise, the first 3 h of which were seated rest. The post-exercise hypotensive response was larger after leg intervals than endurance (AUC: 7540 ± 3853 vs. 3897 ± 2757 mm Hg·min, p = 0.049, 95% CI: 20 to 6764), whereas exercising different limbs elicited similar hypotension (arms: 6420 ± 3947 mm Hg·min, p = 0.48, CI: -1261 to 3896). In contrast, arterial pressure at 22 h was reduced after endurance but not after leg intervals (-8 ± 8 vs. 0 ± 7 mm Hg, p = 0.04, CI: 7 ± 7) or reliably after arm intervals (-4 ± 8 mm Hg, p = 0.18 vs. leg intervals). Regardless, plasma volume expansion at 22 h was similar between leg intervals and endurance (both +5 ± 5%; CI: -5 to 5%) and between leg and arm intervals (arms: +5 ± 7%, CI: -8 to 5%). These results emphasize the relative importance of central and/or systemic factors in post-exercise hypotension, and indicate that markedly diverse exercise profiles can induce substantive hypotension and subsequent hypervolemia. At least for endurance exercise, this hypervolemia may not depend on the

  9. Severe post-renal acute kidney injury, post-obstructive diuresis and renal recovery.

    PubMed

    Hamdi, Aïcha; Hajage, David; Van Glabeke, Emmanuel; Belenfant, Xavier; Vincent, François; Gonzalez, Frédéric; Ciroldi, Magali; Obadia, Edouard; Chelha, Riad; Pallot, Jean-Louis; Das, Vincent

    2012-12-01

    Study Type--Therapy (case series) Level of Evidence 4. What's known on the subject? and What does the study add? The pathophysiology of post-renal acute kidney injury (PR-AKI), i.e. caused by urinary tract obstruction, has been extensively studied in animal models but clinical studies on this subject are outdated, and/or have focused on the mechanisms of 'post-obstructive diuresis' (POD), a potentially life-threatening polyuria that can develop after the release of obstruction. In severe PR-AKI, the risk of occurrence of POD is high. POD occurrence predicts renal recovery without the persistence of severe chronic kidney failure. In the present study, the occurrence of POD and the persistence of chronic renal sequelae could be predicted early from clinical variables at admission before the release of obstruction. • To identify predictors of post-obstructive diuresis (POD) occurrence or severe chronic renal failure (CRF) persistence after the release of urinary tract obstruction in the setting of post-renal acute kidney injury (PR-AKI). • Bi-centre retrospective observational study of all patients with PR-AKI treated in two intensive care units (ICUs) from 1998 to 2010. • Clinical, biological and imaging characteristics on admission and after the release of obstruction were analysed with univariate and, if possible, multivariate analysis to search for predictors of (i) occurrence of POD (diuresis >4 L/day) after the release of obstruction; (ii) persistence of severe CRF (estimated glomerular filtration rate <30 mL/min/1.73 m(2), including end-stage CRF) at 3 months. • On admission, median (range) serum creatinine was 866 (247-3119) µmol/L. • POD occurred in 34 (63%) of the 54 analysable patients. On admission, higher serum creatinine (Odds ratio [OR] 1.002 per 1 µmol/L, 95% confidence interval [CI] 1.000-1.004, P = 0.004), higher serum bicarbonate (OR 1.36 per 1 mmol/L, 95% CI 1.13-1.65, P < 0.001), and urinary retention (OR 6.96, 95% CI 1.34-36.23, P

  10. Imaging Signs in Spontaneous Intracranial Hypotension: Prevalence and Relationship to CSF Pressure.

    PubMed

    Kranz, P G; Tanpitukpongse, T P; Choudhury, K R; Amrhein, T J; Gray, L

    2016-07-01

    Patients with spontaneous intracranial hypotension often exhibit low CSF pressure and changes on brain MR imaging and/or evidence of CSF leak on myelography. We investigated whether individual imaging signs of spontaneous intracranial hypotension correlate with measured CSF pressure and how frequently these 2 markers of spontaneous intracranial hypotension were concordant. We performed a retrospective, cross-sectional study of 99 subjects with spontaneous intracranial hypotension. Prevalence of brain and myelographic imaging signs of spontaneous intracranial hypotension was recorded. CSF pressure among subjects with or without individual imaging signs was compared by using a 2-tailed t test and ANOVA. Concordance between low CSF pressure (≤6 cm H2O) and imaging was defined as the presence of the sign in a subject with low CSF pressure or absence of the sign when pressure was not low. Dural enhancement, brain sagging, and venous distension sign were present in 83%, 61%, and 75% of subjects, respectively, and myelographic evidence of CSF leak was seen in 55%. Marginal correlations between CSF pressure and brain sagging (P = .046) and the venous distension sign (P = .047) were found. Dural enhancement and myelographic evidence of leak were not significantly correlated with CSF pressure. Rates of concordance between imaging signs and low CSF pressure were generally low, ranging from 39% to 55%. Brain and myelographic signs of spontaneous intracranial hypotension correlate poorly with CSF pressure. These findings reinforce the need to base the diagnosis of spontaneous intracranial hypotension on multiple diagnostic criteria and suggest the presence of patient-specific variables that influence CSF pressure in these individuals. © 2016 by American Journal of Neuroradiology.

  11. Vertigo and nystagmus in orthostatic hypotension.

    PubMed

    Choi, J-H; Seo, J-D; Kim, M-J; Choi, B-Y; Choi, Y R; Cho, B M; Kim, J S; Choi, K-D

    2015-04-01

    Generalized cerebral ischaemia from cardiovascular dysfunction usually leads to presyncopal dizziness, but several studies reported a higher frequency of rotatory vertigo in cardiovascular patients. Whether generalized cerebral ischaemia due to cardiovascular disorders may produce objective vestibular dysfunction was investigated. Thirty-three patients with orthostatic dizziness/vertigo due to profound orthostatic hypotension and 30 controls were recruited. All participants underwent recording of eye movements during two orthostatic challenging tests: the Schellong and the squatting-standing tests. Most patients had neuroimaging, and patients with abnormal eye movements were subjected to follow-up evaluations. Symptoms associated with orthostatic dizziness/vertigo included blurred vision, fainting and tinnitus. Ten (30%) of 33 patients developed rotatory vertigo and nystagmus during the Schellong (n = 5) or squatting-standing test (n = 5). Four of them showed pure downbeat nystagmus whilst five had downbeat and horizontal nystagmus with or without torsional component. Patients with orthostatic nystagmus had shorter duration of orthostatic intolerance than those without nystagmus (1.0 ± 1.6 vs. 11.0 ± 9.7 months, P < 0.001). In two patients, orthostatic nystagmus disappeared during follow-up despite the persistence of profound orthostatic hypotension. Generalized cerebral ischaemia caused by orthostatic hypotension induces rotatory vertigo due to objective vestibular dysfunction. The presence of orthostatic vertigo and nystagmus has an association with the duration of orthostatic intolerance. © 2014 EAN.

  12. Orthostatic hypotension, cerebral hypoperfusion, and visuospatial deficits in Lewy body disorders.

    PubMed

    Robertson, Andrew D; Messner, Michelle A; Shirzadi, Zahra; Kleiner-Fisman, Galit; Lee, Joyce; Hopyan, Julia; Lang, Anthony E; Black, Sandra E; MacIntosh, Bradley J; Masellis, Mario

    2016-01-01

    Orthostatic hypotension and cognitive impairment are two non-motor attributes of Lewy body spectrum disorders that impact independence. This proof-of-concept study examined cerebral blood flow (perfusion) as a mediator of orthostatic hypotension and cognition. In fifteen patients with Lewy body disorders, we estimated regional perfusion using pseudo-continuous arterial spin labeling MRI, and quantified orthostatic hypotension from the change in systolic blood pressure between supine and standing positions. Executive, visuospatial, attention, memory, and language domains were characterized by neuropsychological tests. A matching sample of non-demented adults with cerebral small vessel disease was obtained to contrast perfusion patterns associated with comorbid vascular pathology. Compared to the vascular group, patients with Lewy body disorders exhibited lower perfusion to temporal and occipital lobes than to frontal and parietal lobes (q < 0.05). A greater orthostatic drop in systolic pressure was associated with lower occipito-parietal perfusion in these patients (uncorrected p < 0.005; cluster size ≥ 20 voxels). Although orthostatic hypotension and supine hypertension were strongly correlated (r = -0.79, p < 0.001), the patterns of association for each with perfusion were distinct. Specifically, supine hypertension was associated with high perfusion to anterior and middle cerebral arterial territories, as well as with low perfusion to posterior regions. Perfusion within orthostatic hypotension-defined regions was directly related to performance on visuospatial and attention tasks, independent of dementia severity (p < 0.05). These findings provide new insight that regional cerebral hypoperfusion is related to orthostatic hypotension, and may be involved in domain-specific cognitive deficits in Lewy body disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Vasopressor choice for hypotension in elective Cesarean section: ephedrine or phenylephrine?

    PubMed Central

    Gunda, Chandrakala P.; Malinowski, Jennifer; Tegginmath, Aruna; Suryanarayana, Venkatesh G.

    2010-01-01

    Introduction Hypotensive episodes are a common complication of spinal anesthesia during Cesarean section. The purpose of this study was to compare the effectiveness and the side effects of vasopressors, ephedrine and phenylephrine, administered for hypotension during elective Cesarean section under spinal anesthesia. Material and methods The study consisted of 100 selected ASA I/II females scheduled for elective Cesarean section under spinal anesthesia. Each patient was randomly assigned to one of the two double-blind study groups. Group E received 1 ml ephedrine (5 mg/ml) with normal saline if hypotension was present (n=50). Group P received 1 ml phenylephrine (100 µg/ml) with normal saline if hypotension developed (n=50). Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) were compared within and between groups to basal levels at time increments of 0, 2, 4, 6, 8, 10, 15, 20, 25, 30, 45, and 60 min from start of surgery. Incidence of side effects and neonatal outcomes were studied between groups. Results All patients required vasopressor therapy for hypotension. Administration of phenylephrine was associated with significant drop in HR. Changes in SBP, DBP, and MAP were similar in both groups for most observed times. The incidences of nausea/vomiting and tachycardia were significantly higher in the ephedrine group. Conclusions Phenylephrine and ephedrine are acceptable choices to combat maternal hypotension related to spinal anesthesia in elective Cesarean section. Complications of intra-operative nausea and vomiting, tachycardia and bradycardia should be considered when choosing a vasopressor, suggesting phenylephrine may be more appropriate when considering maternal well-being. PMID:22371756

  14. Central Methysergide Prevents Renal Sympathoinhibition and Bradycardia during Hypotensive Hemorrhage

    NASA Technical Reports Server (NTRS)

    Veelken, Roland; Johnson, Kim; Scrogin, Karie E.

    1998-01-01

    Central methysergide prevents renal sympathoinhibition and bradycardia during hypotensive hemorrhage. Mean arterial pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA) were measured in conscious rats during either hemorrhage or cardiopulmonary receptor stimulation with phenylbiguanide (PBG) after intracerebroventricular injection of the 5-HT1/5-HT2-receptor antagonist, methysergide (40 microg). Progressive hemorrhage caused an initial rise (109 +/- 33%) followed by a fall in RSNA (-60 +/- 7%) and a fall in HR (-126 +/- 7 beats/min). Methysergide delayed the hypotension and prevented both the sympathoinhibitory and bradycardic responses to hemorrhage. Systemic 5-HT3-receptor blockade did not influence responses to hemorrhage. The PBG infusion caused transient depressor(-25 +/- 6 mmHg), bradycardic (-176 +/- 40 beats/min), and renal sympathostimulatory (182 +/-47% baseline) responses that were not affected by central methysergide (-20 +/- 6 mmHg, -162 +/- 18 beats/min, 227 +/- 46% baseline). These data indicate that a central serotonergic receptor-mediated component contributes to the sympathoinhibitory and bradycardic responses to hypotensive hemorrhage in conscious rats. Furthermore, the same central 5-HT-receptor populations involved in reflex responses to hypotensive hemorrhage probably do not mediate the sympathoinhibitory response to cardiopulmonary chemosensitive 5-HT3 receptors.

  15. Effects of weight-based ultrafiltration rate limits on intradialytic hypotension in hemodialysis.

    PubMed

    Pirkle, James L; Comeau, Mary E; Langefeld, Carl D; Russell, Gregory B; Balderston, Somer S; Freedman, Barry I; Burkart, John M

    2018-04-01

    High ultrafiltration (UF) rates can result in intradialytic hypotension and are associated with increased mortality. The effects of a weight-based UF rate limit on intradialytic hypotension and the potential for unwanted fluid weight gain and hospitalizations for volume overload are unknown. This retrospective cohort study examined 123 in-center hemodialysis patients at one facility who transitioned to 13 mL/kg/h maximum UF rates. Patients were studied for an 8 week UF rate limit exposure period and compared to the 8-week period immediately prior, during which the cohort served as its own historical control. The primary outcomes were frequency of intradialytic hypotension events and percentage of treatments with a hypotension event. The delivered UF rate was lower during the exposure compared to the baseline period (mean UF rate 7.90 ± 4.45 mL/kg/h vs. 8.92 ± 5.64 mL/kg/h; P = 0.0005). The risk of intradialytic hypotension was decreased during the exposure compared to baseline period (event rate per treatment 0.0569 vs. 0.0719, OR 0.78 [95% CI 0.62-1.00]; P = 0.0474), as was the risk of having a treatment with a hypotension event (percentage of treatments with event 5.2% vs. 6.8%, OR 0.75 [95% CI 0.58-0.96]; P = 0.0217). Subgroup analyses demonstrated that these findings were attributable to patients with high baseline UF rates. Statistically significant differences in all-cause or volume overload-related hospitalization were not observed during the exposure period. A weight-based UF rate limit of 13 mL/kg/h was associated with a decrease in the rate of intradialytic hypotension events among in-center hemodialysis patients. © 2017 International Society for Hemodialysis.

  16. Recent advances in the treatment of orthostatic hypotension

    NASA Technical Reports Server (NTRS)

    Robertson, D.; Davis, T. L.

    1995-01-01

    Orthostatic hypotension is a fall in blood pressure on standing that causes symptoms of dizziness, visual changes, and discomfort in the head and neck. The goal of treatment is the improvement of the patient's functional capacity, rather than a target blood pressure. For treatment to be successful, it must be individualized. Non-pharmalogic interventions include carefully managed exercise, scheduled activities, and monitoring of the environmental temperature. Agents such as fludrocortisone, midodrine, and epoetin alfa offer successful pharmacologic interventions. Although these measures ease the symptoms of orthostatic hypotension, current approaches neither reverse nor stabilize the disease process in autonomic disorders.

  17. Permissive hypotension in extremely low birth weight infants (≤1000 gm).

    PubMed

    Ahn, So Yoon; Kim, Eun Sun; Kim, Jin Kyu; Shin, Jeong Hee; Sung, Se In; Jung, Ji Mi; Chang, Yun Sil; Park, Won Soon

    2012-07-01

    We performed this study to evaluate the safety of permissive hypotension management in extremely low birth weight infants (ELBWIs). Medical records of all inborn ELBWIs admitted to Samsung Medical Center from January 2004 to December 2008 were reviewed retrospectively. Of a total of 261 ELBWIs, 47 (18%) required treatment for hypotension (group T), 110 (42%) remained normotensive (group N), and 104 (40%) experienced more than one episode of hypotension without treatment (group P) during the first 72 hours of life. Treatment of hypotension included inotropic support and/or fluid loading. Birth weight and Apgar scores were significantly lower in the T group than the other two groups. In the N group, the rate of pathologically confirmed maternal chorioamnionitis was significantly higher than other two groups, and the rate was higher in the P group than the T group. After adjusting for covariate factors, no significant differences in mortality and major morbidities were found between the N and P groups. However, the mortality rate and the incidence of intraventricular hemorrhage (≥stage 3) and bronchopulmonary dysplasia (≥moderate) were significantly higher in the T group than the other two groups. Long term neurodevelopmental outcomes were not significantly different between the N and P groups. Close observation of hypotensive ELBWIs who showed good clinical perfusion signs without intervention allowed to avoid unnecessary medications and resulted in good neurological outcomes.

  18. Echocardiographic predictors of change in renal function with intravenous diuresis for decompensated heart failure.

    PubMed

    Gannon, Stephen A; Mukamal, Kenneth J; Chang, James D

    2018-06-14

    The aim of this study was to identify echocardiographic predictors of improved or worsening renal function during intravenous diuresis for decompensated heart failure. Secondary aim included defining the incidence and clinical risk factors for acute changes in renal function with decongestion. A retrospective review of 363 patients admitted to a single centre for decompensated heart failure who underwent intravenous diuresis and transthoracic echocardiography was conducted. Clinical, echocardiographic, and renal function data were retrospectively collected. A multinomial logistic regression model was created to determine relative risk ratios for improved renal function (IRF) or worsening renal function (WRF). Within this cohort, 36% of patients experienced WRF, 35% had stable renal function, and 29% had IRF. Patients with WRF were more likely to have a preserved left ventricular ejection fraction compared with those with stable renal function or IRF (P = 0.02). Patients with IRF were more likely to have a dilated, hypokinetic right ventricle compared with those with stable renal function or WRF (P ≤ 0.01), although this was not significant after adjustment for baseline characteristics. Left atrial size, left ventricular linear dimensions, and diastolic function did not significantly predict change in renal function. An acute change in renal function occurred in 65% of patients admitted with decompensated heart failure. WRF was statistically more likely in patients with a preserved left ventricular ejection fraction. A trend towards IRF was noted in patients with global right ventricular dysfunction. © 2018 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

  19. Prehospital Nitroglycerin in Tachycardic Chest Pain Patients: A Risk for Hypotension or Not?

    PubMed

    Proulx, Marie-Hélène; de Montigny, Luc; Ross, Dave; Vacon, Charlene; Juste, Louis Enock; Segal, Eli

    2017-01-01

    The American Heart Association guidelines (AHA) guidelines list tachycardia as a contraindication for the administration of nitroglycerin (NTG), despite limited evidence of adverse events. We sought to determine whether NTG administered for chest pain was a predictor of hypotension (systolic blood pressure <90 mmHg) in patients with tachycardia, compared to patients without tachycardia (50≥ heart rate ≤100). We performed a retrospective cohort study using patient care reports completed by basic life support (BLS) providers in a large urban Canadian EMS system for the period 2010-2012. We used logistic regression to test the association between post-NTG hypotension and tachycardia, independent of pre-NTG blood pressure, age, sex, and comorbidities. Using identical models, we tested four secondary outcomes (drop in blood pressure, reduced consciousness, bradycardia, and cardiac arrest). The cohort included 10,308 patients who were administered NTG by BLS in the prehospital setting; 2,057 (20%) of patients were tachycardic before NTG administration. Hypotension occurred in 320 of all patients (3.1%): 239 without tachycardia (2.9%) and 81 with tachycardia (3.9%). Compared to non-tachycardic patients, tachycardic patients showed increased adjusted odds of hypotension (AOR: 1.60; 95% CI: 1.23-2.08) or of a drop in blood pressure of 30mm Hg or greater (AOR: 1.11; CI: 1.00-1.24). Tachycardia was associated with decreased odds of bradycardia (OR: 0.33; CI: 0.17-0.64). We did not find a significant association between tachycardia and either post-NTG reduced level of consciousness or cardiac arrest. We did find a strong, significant association between pre-NTG blood pressure and post-NTG hypotension (AOR for units of 10mmHg: 0.64; CI: 0.61-0.69). Hypotension following prehospital administration of NTG was infrequent in patients with chest pain. However, while the absolute risk of NTG-induced hypotension was low, patients with pre-NTG tachycardia had a significant increase

  20. Hypoalbuminemia is an important risk factor of hypotension during hemodialysis.

    PubMed

    Nakamoto, Hidetomo; Honda, Nobuko; Mimura, Taku; Suzuki, Hiromichi

    2006-10-01

    Hypotension during hemodialysis (HD) is an important problem in patients on HD. To investigate the risk factors that contribute to the hypotension during HD, we compared background factors of hypotensive (HP) patients during HD. Among 58 patients undergoing HD in Tamura Memorial Hospital, 12 patients could not continue full HD because of hypotension. We compared the data of ultrafiltration volume, cardiothoracic ratio (CTR), total protein (TP), serum albumin, blood urea nitrogen (BUN), serum creatinine, total cholesterol (TC), hemoglobin (Hb), blood glucose (BS), brain natriuretic peptide (BNP), and cardiac function between HP patients (HP group; n=12) and sex- and age-matched control patients (NP group; n=12). There were no significant differences of age, sex, and duration of HD between the 2 groups. Cardiothoracic ratio is bigger and BNP is higher in the HP group compared with the NP group (CTR: HP 55.8+/-2.9% vs. NP 47.7+/-1.1%, p=0.0165; BNP: HP 602+/-171 vs. NP 147+/-38, p=0.0167). Serum albumin in the HP group is significantly lower compared with the NP group (HP 3.2+/-0.1 g/dL vs. NP 3.5+/-0.1 g/dL, p=0.0130). However, there were no significant differences of ultrafiltration rate (UFR), BS, TC, Hb, and cardiac function between the 2 groups. There is a significant negative correlation between changes of systolic blood pressure (delta systolic blood pressure) and serum albumin in these patients (r=-0.598, p=0.0016). From these data, we conclude that hypoalbuminemia is a major risk factor of hypotension during HD.

  1. Body water handling in response to hypertonic-saline induced diuresis in fasting northern elephant seal pups (Mirounga angustirostris)

    NASA Technical Reports Server (NTRS)

    Ortiz, Rudy M.; Wade, Charles E.; Ortiz, C. Leo

    2003-01-01

    During natural fasting conditions in postweaned northern elephant seal (NES) (Mirounga angustirostris) pups, urinary water loss is minimized and percent total body water (TBW) is maintained constant. However, following infusion of hypertonic saline, glomerular filtration rate (GFR) and urine output increased in fasting pups. Therefore, we quantified the magnitude of the hypernatremia-induced diuresis relative to the animal's total body water (TBW) pool and the percentage of filtered water reabsorbed. Following a 24 h control period, naturally fasting NES pups (n=7) were infused (4 ml min(-1)) with hypertonic saline (16.7%) at a dose of 3 mmol NaCl kg(-1) body mass. Total body water was estimated prior to infusion by tritium dilution, GFR was estimated by standard creatinine clearance, and urine output (V) was measured for 24 h during the control and post infusion periods. Percentage of filtered water reabsorbed was calculated as (1-(V/GFR))x100. Twenty-four hours following the infusion, GFR (control: 69+/-12 ml min(-1) and post-infusion: 118+/-19 ml min(-1); mean+/-S.E.) increased 77+/-28% above control and the percentage of filtered water reabsorbed was decreased 0.4+/-0.1%. The increase in urine output (control: 218+/-47 ml d(-1) and post-infusion: 883+/-92 ml d(-1)) accounted for 1.7+/-0.2% of the pups' TBW. The hypernatremia-induced diuresis was accompanied by the loss of body water indicating the lack of water retention. Although the 77% increase in GFR was only associated with a 0.4% decrease in the percentage of filtered water reabsorbed, this decrease was significant enough to result in a 4-fold increase in urine output. Despite the observed diuresis, fasting NES pups appear to possess an efficient water recycling mechanism requiring only a small percentage of body water to excrete an excess salt load. This water recycling mechanism may allow pups to avoid negative perturbations in body water as they initiate feeding in a marine environment following the

  2. Severe bradycardia and prolonged hypotension in ciguatera.

    PubMed

    Chan, Thomas Yan Keung

    2013-06-01

    Ciguatera results when ciguatoxin-contaminated coral reef fish from tropical or subtropical waters are consumed. The clinical features that present in affected persons are mainly gastrointestinal, neurological, general, and much less commonly, cardiovascular. We report the case of a 50-year-old man who developed the characteristic combination of acute gastrointestinal and neurological symptoms after the consumption of an unidentified coral reef fish head. In addition to those symptoms, he developed dizziness, severe bradycardia (46 bpm) and prolonged hypotension, which required the administration of intravenous atropine and over three days of intravenous fluid replacement with dopamine infusion. Patients with ciguatera can develop severe bradycardia and prolonged hypotension. Physicians should recognise the possible cardiovascular complications of ciguatera and promptly initiate treatment with intravenous atropine, intravenous fluid replacement and inotropic therapy if such complications are observed.

  3. Vitamin D deficiency is associated with orthostatic hypotension in oldest-old women.

    PubMed

    Annweiler, C; Schott, A-M; Rolland, Y; Beauchet, O

    2014-09-01

    Orthostatic hypotension, a condition that mostly affects 'oldest-old' (i.e. ≥80 years) adults, is primarily explained by age-related dysfunction of blood pressure control. Vitamin D may contribute to blood pressure control. The aim of this study was to determine whether vitamin D deficiency is associated with orthostatic hypotension in oldest-old adults. Cross-sectional analysis at baseline of the EPIDOS study. Five French areas. A total of 329 community-dwelling oldest-old women (mean age 83.3 ± 0.2 years). Orthostatic hypotension was defined as a systolic blood pressure drop of ≥20 mmHg and/or a diastolic blood pressure drop of ≥10 mmHg within 3 min of standing. Vitamin D deficiency was defined as a serum 25-hydroxyvitamin D (25OHD) concentration ≤10 ng mL(-1) . Covariates included in the models were age, body mass index, diabetes mellitus, supine mean arterial pressure, number of drugs taken per day, use of antihypertensive or psychoactive drugs, cognition, quadriceps strength, current smoking, alcohol consumption, serum concentrations of parathyroid hormone, calcium and creatinine and season of testing. Diastolic orthostatic hypotension was observed more often among women with vitamin D deficiency (19.2%) compared to those without (10.0%; P = 0.03). There was an inverse linear association between 25OHD concentration and change in diastolic blood pressure after 3 min of standing (adjusted β = -0.07, P = 0.046). Similarly, 25OHD deficiency was associated with orthostatic hypotension [adjusted odds ratio (OR) 3.36, P = 0.004], specifically with diastolic orthostatic hypotension (adjusted OR 3.81, P = 0.003). 25OHD deficiency was associated with orthostatic hypotension in oldest-old women, due to a greater drop in diastolic blood pressure on standing. This finding may lead to better understanding of the pathophysiology of falls in oldest-old adults with vitamin D deficiency. © 2014 The Association for the Publication of the Journal of

  4. Investigation of postural hypotension due to static prolonged standing in female workers.

    PubMed

    Kabe, Isamu; Tsuruoka, Hiroko; Tokujitani, Yoko; Endo, Yuichi; Furusawa, Mami; Takebayashi, Toru

    2007-07-01

    The "Just-in-Time system" improves productivity and efficiency through cost reduction while it makes workers work in a standing posture. The aim of this study was to investigate the prevalence of postural hypotension in females during prolonged standing work, and to discuss preventive methods. Twelve female static standing workers (mean age+/-standard deviation; 32+/-14 yr old), 6 male static standing workers (30+/-4 yr old), 10 female walking workers (27+/-7 yr old) and 9 female desk workers (31+/-5 yr old) in a certain telecommunications equipment manufacturing factory agreed to participate in this study. All participants received an interview with an occupational physician, and performed the standing up test before working and ambulatory blood pressure monitoring (ABPM) while working. Although the blood pressure of the standing up test did not differ among the groups, mean pulse rates on standing up significantly increased in every group. Hypotension rates in the female standing workers' group by ABPM were 9 persons of 12 participants (75%) for systolic blood pressure (SBP), and were 11 persons of 12 participants (92%) for diastolic blood pressure (DBP). There were significantly higher than those in the female desk workers' group, none of 9 participants (0%) for SBP and 2 of 9 participants (22%) for DBP. The hypotension rates both male standing and female walking worker groups did not differ. Because all 8 workers who were found to have postural hypotension by the standing up test had decreased SBP and/or DBP by ABPM, it is suggested that persons at high risk of postural hypotension during standing work could be screened by the standing up test. The mechanism of postural hypotension may be a decrease of venous return due to leg swelling, and neurocardiogenic or vasovagal response. Preventing the congestion of the lower limbs by walking, managing standing time and wearing elastic hose to keep the amount of the venous return could prevent postural hypotension

  5. Comparative hemodynamic effects of hypotension induced by diadenosine tetraphosphate (AP4A) and ATP in dogs.

    PubMed

    Takeda, Shohei; Inada, Yutaka; Fukui, Noriyuki; Tomaru, Teruaki

    1997-03-01

    ATP and diadenosine tetraphosphate (AP 4 A) have been shown to produce vasodilation mediated by P 1 - and P 2 -purinoceptor, respectively. The differing mechanisms involved in this vasodilating activity may induce different systemic hemodynamic changes. We compared the hemodynamic effects of AP 4 A-induced hypotension with those induced by ATP. Fourteen mongrel dogs were anesthetized with 0.87% halothane in oxygen (1 MAC). After the baseline period, mean arterial pressure was reduced to 60 mmHg for 60 min by the infusion of AP 4 A or ATP. The ATP- and AP 4 A-induced hypotension resulted in a maximum reduction in systemic vascular resistance of 43% and 46%, respectively (P<0.01), associated with a significant increase in stroke volume index. With ATP, a 20% of maximum increase (P<0.05) in cardiac index (CI) was observed during the induced hypotension. In contrast, AP 4 A-induced hypotension did not result in any changes in CI throughout the observation period. The varying results concerning CI during the ATP- and AP 4 A-induced hypotension were probably due to differences in ventricular filling pressure, since AP 4 A-induced hypotension was associated with decreases (P<0.01) in both right atrial and pulmonary capillary wedge pressures, whereas neither of these variables significantly changed with ATP. The hypotension induced by either ATP or AP 4 A was associated with a significant decrease in heart rate (HR). However, both the magnitude and duration of decreases in HR due to ATP-induced hypotension were more pronounced than those seen with AP 4 A. In conclusion, while both drugs were equally capable of inducing hypotension, our results suggest that AP 4 A was more suitable for induced hypotension because of its potent vasodilatory action with venodilation and less negative chronotropic action.

  6. A sequential compression mechanical pump to prevent hypotension during elective cesarean section under spinal anesthesia.

    PubMed

    Sujata, N; Arora, D; Panigrahi, B P; Hanjoora, V M

    2012-04-01

    Spinal anesthesia is a standard technique for cesarean section but can cause hypotension which may be related to venous pooling secondary to progesterone-induced decreases in vascular tone. This study investigated the use of a sequential compression mechanical pump with thigh-high sleeves with compression cycles timed to venous refilling. We hypothesized that this would recruit pooled venous blood from the lower limbs, maintain the central blood volume and thus decrease the incidence of hypotension. One hundred parturients scheduled for elective cesarean section under spinal anesthesia were recruited and randomly assigned to use of either a mechanical pump (Group M) or control (Group C). A standardized protocol for co-hydration and anesthesia was followed. Hypotension, defined as a decrease in systolic blood pressure by >20% from baseline, was treated with 6-mg boluses of intravenous ephedrine. The incidence of hypotension was defined as the primary outcome. Median ephedrine requirement was taken as a measure of the severity of hypotension. Hypotension occurred in 12 of 47 (25.5%) patients in Group M compared to 27 of 45 (60%) in Group C (P=0.001). The median [range] ephedrine dose was greater in Group C (12 [0-24]mg) compared to Group M (0 [0-12]mg) (P<0.001). There was no difference between groups in the time to onset of hypotension. The use of a sequential compression mechanical pump that detects venous refilling and cycles accordingly, reduced the incidence and severity of hypotension after spinal anesthesia for cesarean section. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Randomized Withdrawal Study of Patients With Symptomatic Neurogenic Orthostatic Hypotension Responsive to Droxidopa

    PubMed Central

    Freeman, Roy; Mathias, Christopher J.; Low, Phillip; Hewitt, L. Arthur; Kaufmann, Horacio

    2015-01-01

    Abstract— We evaluated whether droxidopa, a prodrug converted to norepinephrine, is beneficial in the treatment of symptomatic neurogenic orthostatic hypotension, which results from failure to generate an appropriate norepinephrine response to postural challenge. Patients with symptomatic neurogenic orthostatic hypotension and Parkinson disease, multiple system atrophy, pure autonomic failure, or nondiabetic autonomic neuropathy underwent open-label droxidopa titration (100–600 mg, 3× daily). Responders then received an additional 7-day open-label treatment at their individualized dose. Patients were subsequently randomized to continue with droxidopa or withdraw to placebo for 14 days. We then assessed patient-reported scores on the Orthostatic Hypotension Questionnaire and blood pressure measurements. Mean worsening of Orthostatic Hypotension Questionnaire dizziness/lightheadedness score from randomization to end of study (the primary outcome; N=101) was 1.9±3.2 with placebo and 1.3±2.8 units with droxidopa (P=0.509). Four of the other 5 Orthostatic Hypotension Questionnaire symptom scores and all 4 symptom-impact scores favored droxidopa, with statistical significance for the patient’s self-reported ability to perform activities requiring standing a short time (P=0.033) and standing a long time (P=0.028). Furthermore, a post hoc analysis of a predefined composite score of all symptoms (Orthostatic Hypotension Questionnaire composite) demonstrated a significant benefit for droxidopa (P=0.013). There was no significant difference between groups for standing systolic blood pressure (P=0.680). Droxidopa was well tolerated. In summary, this randomized withdrawal droxidopa study failed to meet its primary efficacy end point. Additional clinical trials are needed to confirm that droxidopa is beneficial in symptomatic neurogenic orthostatic hypotension, as suggested by the positive secondary outcomes of this trial. Clinical Trial Registration— URL: http

  8. Randomized withdrawal study of patients with symptomatic neurogenic orthostatic hypotension responsive to droxidopa.

    PubMed

    Biaggioni, Italo; Freeman, Roy; Mathias, Christopher J; Low, Phillip; Hewitt, L Arthur; Kaufmann, Horacio

    2015-01-01

    We evaluated whether droxidopa, a prodrug converted to norepinephrine, is beneficial in the treatment of symptomatic neurogenic orthostatic hypotension, which results from failure to generate an appropriate norepinephrine response to postural challenge. Patients with symptomatic neurogenic orthostatic hypotension and Parkinson disease, multiple system atrophy, pure autonomic failure, or nondiabetic autonomic neuropathy underwent open-label droxidopa titration (100-600 mg, 3× daily). Responders then received an additional 7-day open-label treatment at their individualized dose. Patients were subsequently randomized to continue with droxidopa or withdraw to placebo for 14 days. We then assessed patient-reported scores on the Orthostatic Hypotension Questionnaire and blood pressure measurements. Mean worsening of Orthostatic Hypotension Questionnaire dizziness/lightheadedness score from randomization to end of study (the primary outcome; N=101) was 1.9±3.2 with placebo and 1.3±2.8 units with droxidopa (P=0.509). Four of the other 5 Orthostatic Hypotension Questionnaire symptom scores and all 4 symptom-impact scores favored droxidopa, with statistical significance for the patient's self-reported ability to perform activities requiring standing a short time (P=0.033) and standing a long time (P=0.028). Furthermore, a post hoc analysis of a predefined composite score of all symptoms (Orthostatic Hypotension Questionnaire composite) demonstrated a significant benefit for droxidopa (P=0.013). There was no significant difference between groups for standing systolic blood pressure (P=0.680). Droxidopa was well tolerated. In summary, this randomized withdrawal droxidopa study failed to meet its primary efficacy end point. Additional clinical trials are needed to confirm that droxidopa is beneficial in symptomatic neurogenic orthostatic hypotension, as suggested by the positive secondary outcomes of this trial. http://www.clinicaltrials.gov. Unique identifier: NCT00633880

  9. Lack of causal association between spontaneous intracranial hypotension and cranial cerebrospinal fluid leaks.

    PubMed

    Schievink, Wouter I; Schwartz, Marc S; Maya, M Marcel; Moser, Franklin G; Rozen, Todd D

    2012-04-01

    Spontaneous intracranial hypotension is an important cause of headaches and an underlying spinal CSF leak can be demonstrated in most patients. Whether CSF leaks at the level of the skull base can cause spontaneous intracranial hypotension remains a matter of controversy. The authors' aim was to examine the frequency of skull base CSF leaks as the cause of spontaneous intracranial hypotension. Demographic, clinical, and radiological data were collected from a consecutive group of patients evaluated for spontaneous intracranial hypotension during a 9-year period. Among 273 patients who met the diagnostic criteria for spontaneous intracranial hypotension and 42 who did not, not a single instance of CSF leak at the skull base was encountered. Clear nasal drainage was reported by 41 patients, but a diagnosis of CSF rhinorrhea could not be established. Four patients underwent exploratory surgery for presumed CSF rhinorrhea. In addition, the authors treated 3 patients who had a postoperative CSF leak at the skull base following the resection of a cerebellopontine angle tumor and developed orthostatic headaches; spinal imaging, however, demonstrated the presence of a spinal source of CSF leakage in all 3 patients. There is no evidence for an association between spontaneous intracranial hypotension and CSF leaks at the level of the skull base. Moreover, the authors' study suggests that a spinal source for CSF leakage should even be suspected in patients with orthostatic headaches who have a documented skull base CSF leak.

  10. Hypotensive effect of agmatine, arginine metabolite, is affected by NO synthase.

    PubMed

    Gerová, M; Török, J

    2004-01-01

    The metabolites of arginine were recently shown to be involved in cardiovascular control. The study addresses the general cardiovascular response of anaesthetized rats to agmatine, a decarboxylated arginine. The relation between two arginine metabolic pathways governed by arginine decarboxylase and nitric oxide synthase was investigated. Intravenous administration of agmatine 30 and 60 microM/0.1 ml saline elicited remarkable hypotension of 42.6+/-4.6 and 70.9+/-6.5 mm Hg, respectively. The hypotension was characterized by long duration with half-time of return 171.6+/-2.9 and 229.2+/-3.8 s, respectively. The time of total blood pressure BP recovery was about 10 min. Dose-dependent relaxation to agmatine was also found in aorta rings in vitro. Both doses of agmatine administered 60-180 min after NO synthase inhibition L-NAME 40 mg/kg i.v. caused greater hypotension 59.0+/-7.6 and 95.8 8.8 mm Hg P<0.01 both compared to animals with intact NO synthase, but this was accompanied by a significant shortening of the half-time of BP return. If agmatine was administered to hypertensive NO-deficient rats treated with 40 mg/kg/day L-NAME for 4 weeks, similar significant enhancement of hypotension was observed at both agmatine doses, again with a significant shortening of half-time of BP return. It can be summarized that the long-lasting hypotension elicited by agmatine was amplified after acute or chronic NO synthase inhibition, indicating a feedback relation between the two metabolic pathways of arginine.

  11. Hypotensive Anesthesia versus Normotensive Anesthesia during Major Maxillofacial Surgery: A Review of the Literature

    PubMed Central

    Yoav, Leiser; Abu el-Naaj, Imad

    2015-01-01

    Steady blood pressure within normal limits during surgery is one of the markers of the ideal and skillful anesthesia. Yet, reduced blood pressure is advantageous in some settings because it can contribute to a reduction in overall blood loss and improve the surgical field conditions. Controlled hypotension during anesthesia or hypotensive anesthesia is often used in major maxillofacial operations. Since hypotensive anesthesia carries the risk of hypoperfusion to important organs and tissues, mainly the brain, heart, and kidneys, it cannot be applied safely in all patients. In this paper we review the medical literature regarding hypotensive anesthesia during major maxillofacial surgery, the means to achieve it, and the risks and benefits of this technique, in comparison to normotensive anesthesia. PMID:25811042

  12. Prehospital high-dose sublingual nitroglycerin rarely causes hypotension.

    PubMed

    Clemency, Brian M; Thompson, Jeffrey J; Tundo, Gina N; Lindstrom, Heather A

    2013-10-01

    High-dose intravenous nitroglycerin is a common in-hospital treatment for respiratory distress due to congestive heart failure (CHF) with hypertension. Intravenous (IV) nitroglycerin administration is impractical in the prehospital setting. In 2011, a new regional Emergency Medical Services (EMS) protocol was introduced allowing advanced providers to treat CHF with high-dose oral nitroglycerin. The protocol calls for patients to be treated with two sublingual tabs (0.8 mg) when systolic blood pressure (SBP) was >160 mm Hg, or three sublingual tabs (1.2 mg) when SBP was >200 mm Hg, every five minutes as needed. Hypothesis/Problem To assess the protocol's safety, the incidence of hypotension following prehospital administration of multiple simultaneous nitroglycerin (MSN) tabs by EMS providers was studied. This study was a retrospective cohort study of patients from a single commercial EMS agency over a 6-month period. Records from patients with at least one administration of MSN were reviewed. For each administration, the first documented vital signs pre- and post-administration were compared. Administrations were excluded if pre- or post-administration vital signs were missing. One hundred case-patients had at least one MSN administration by an advanced provider during the study period. Twenty-five case-patients were excluded due to incomplete vital signs. Seventy-five case-patients with 95 individual MSN administrations were included for analysis. There were 65 administrations of two tabs, 29 administrations of three tabs, and one administration of four tabs. The mean change in SBP following MSN was -14.7 mm Hg (SD = 30.7; range, +59 to -132). Three administrations had documented systolic hypotension in the post-administration vital signs (97/71, 78/50 and 66/47). All three patients were over 65 years old, were administered two tabs, had documented improved respiratory status, and had repeat SBP of at least 100. The incidence of hypotension following MSN

  13. Outcomes following trauma laparotomy for hypotensive trauma patients: a UK military and civilian perspective.

    PubMed

    Marsden, Max; Carden, Rich; Navaratne, Lalin; Smith, Iain M; Penn-Barwell, Jowan G; Kraven, Luke M; Brohi, Karim; Tai, Nigel R M; Bowley, Douglas M

    2018-05-25

    The management of trauma patients has changed radically in the last decade and studies have shown overall improvements in survival. However, reduction in mortality for the many may obscure a lack of progress in some high-risk patients. We sought to examine the outcomes for hypotensive patients requiring laparotomy in UK military and civilian cohorts. We undertook a review of two prospectively maintained trauma databases; the UK Joint Theatre Trauma Registry (JTTR) for the military cohort (4th February 2003 to 21st September 2014), and the trauma registry of the Royal London Hospital MTC (1st January 2012 to 1st January 2017) for civilian patients. Adults undergoing trauma laparotomy within 90 minutes of arrival at the Emergency Department (ED) were included. Hypotension was present on arrival at the ED in 155/761 (20.4%) military patients. Mortality was higher in hypotensive casualties 25.8% vs 9.7% normotensive casualties (p<0.001). Hypotension was present on arrival at the ED in 63/176 (35.7%) civilian patients. Mortality was higher in hypotensive patients 47.6% vs 12.4% normotensive patients (p<0.001). In both cohorts of hypotensive patients neither the average injury severity, the prehospital time, the ED arrival SBP, nor mortality rate changed significantly during the study period. Despite improvements in survival after trauma for patients overall, the mortality for patients undergoing laparotomy who arrive at the Emergency Department with hypotension has not changed and appears stubbornly resistant to all efforts. Specific enquiry and research should continue to be directed at this high-risk group of patients. IV; Observational Cohort Study.

  14. Effects of Sacubitril/Valsartan (LCZ696) on Natriuresis, Diuresis, Blood Pressures, and NT-proBNP in Salt-Sensitive Hypertension.

    PubMed

    Wang, Tzung-Dau; Tan, Ru-San; Lee, Hae-Young; Ihm, Sang-Hyun; Rhee, Moo-Yong; Tomlinson, Brian; Pal, Parasar; Yang, Fan; Hirschhorn, Elizabeth; Prescott, Margaret F; Hinder, Markus; Langenickel, Thomas H

    2017-01-01

    Salt-sensitive hypertension (SSH) is characterized by impaired sodium excretion and subnormal vasodilatory response to salt loading. Sacubitril/valsartan (LCZ696) was hypothesized to increase natriuresis and diuresis and result in superior blood pressure control compared with valsartan in Asian patients with SSH. In this randomized, double-blind, crossover study, 72 patients with SSH received sacubitril/valsartan 400 mg and valsartan 320 mg once daily for 4 weeks each. SSH was diagnosed if the mean arterial pressure increased by ≥10% when patients switched from low (50 mmol/d) to high (320 mmol/d) sodium diet. The primary outcome was cumulative 6- and 24-hour sodium excretion after first dose administration. Compared with valsartan, sacubitril/valsartan was associated with a significant increase in natriuresis (adjusted treatment difference: 24.5 mmol/6 hours, 50.3 mmol/24 hours, both P<0.001) and diuresis (adjusted treatment difference: 291.2 mL/6 hours, P<0.001; 356.4 mL/24 hours, P=0.002) on day 1, but not on day 28, and greater reductions in office and ambulatory blood pressure on day 28. Despite morning dosing of both drugs, ambulatory blood pressure reductions were more pronounced at nighttime than at daytime or the 24-hour average. Compared with valsartan, sacubitril/valsartan significantly reduced N-terminal pro B-type natriuretic peptide levels on day 28 (adjusted treatment difference: -20%; P=0.001). Sacubitril/valsartan and valsartan were safe and well tolerated with no significant changes in body weight or serum sodium and potassium levels with either treatments. In conclusion, sacubitril/valsartan compared with valsartan was associated with short-term increases in natriuresis and diuresis, superior office and ambulatory blood pressure control, and significantly reduced N-terminal pro B-type natriuretic peptide levels in Asian patients with SSH. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01681576. © 2016 American Heart Association, Inc.

  15. Risk of intraoperative hypotension with loop diuretics: a randomized controlled trial.

    PubMed

    Khan, Nadia A; Campbell, Norman R; Frost, Shaun D; Gilbert, Ken; Michota, Frank A; Usmani, Ali; Seal, Doug; Ghali, William A

    2010-11-01

    There is growing concern regarding the safety of blood pressure-lowering medications administered during the perioperative period. Whether loop diuretics also induce intraoperative hypotension is uncertain. Our objective was to compare the effects of continuing or withholding furosemide on the day of noncardiac elective surgery on intraoperative hypotension among chronic users of furosemide. A double blind, randomized, placebo controlled trial was conducted at 3 North American university centers between September 2000 and December 2006. Participants were randomly assigned in a 1:1 ratio to receive either furosemide or placebo on the day of surgery. The primary outcome was risk of developing intraoperative hypotension. A priori secondary outcomes included risk of heart failure; composite cardiovascular event (myocardial infarction, arrhythmia, stroke or transient ischemic attack, or death); and change in renal function and electrolytes. Of the 212 patients enrolled, 193 patients underwent surgery. There was no significant difference in risk of developing intraoperative hypotension between the furosemide (49%) and placebo (51.9%) groups (relative risk [RR], 0.95; 95% confidence interval [CI], 0.72-1.24; P = .78). The intraoperative administration of vasopressors and fluids were similar between both groups. The risk of developing postoperative cardiovascular events was not significantly different between those randomized to furosemide (4.8%) or placebo (2.8%) (RR, 1.73; 95% CI, 0.42-7.06; P = .49). There was no significant difference in renal function or electrolytes between the 2 groups. Among elective, noncardiac surgeries in patients chronically treated with furosemide, the administration of furosemide on the day of surgery did not significantly increase the risk for intraoperative hypotension. Copyright © 2010 Elsevier Inc. All rights reserved.

  16. Droxidopa: a review of its use in symptomatic neurogenic orthostatic hypotension.

    PubMed

    Keating, Gillian M

    2015-02-01

    The norepinephrine prodrug droxidopa (NORTHERA™) is approved in the US for the treatment of orthostatic dizziness, lightheadedness, or the 'feeling that you are about to black out' in adults with symptomatic neurogenic orthostatic hypotension associated with primary autonomic failure (e.g. Parkinson's disease, multiple system atrophy or pure autonomic failure), dopamine β-hydroxylase deficiency or nondiabetic autonomic neuropathy. This article reviews the clinical efficacy and tolerability of droxidopa in symptomatic neurogenic orthostatic hypotension, as well as summarizing its pharmacological properties. Oral droxidopa was effective in the shorter-term treatment of patients with symptomatic neurogenic orthostatic hypotension, with improvements seen in symptoms, the impact of symptoms on daily activities and standing systolic blood pressure. More data are needed to confirm the longer-term efficacy of droxidopa. Droxidopa was generally well tolerated, although patients should be monitored for supine hypertension.

  17. Permissive hypotension in bleeding trauma patients: helpful or not and when?

    PubMed

    Gourgiotis, Stavros; Gemenetzis, George; Kocher, Hemant M; Aloizos, Stavros; Salemis, Nikolaos S; Grammenos, Stylianos

    2013-12-01

    Severity of hemorrhage and rate of bleeding are fundamental factors in the outcomes of trauma. Intravenous administration of fluid is the basic treatment to maintain blood pressure until bleeding is controlled. The main guideline, used almost worldwide, Advanced Trauma Life Support, established by the American College of Surgeons in 1976, calls for aggressive administration of intravenous fluids, primarily crystalloid solutions. Several other guidelines, such as Prehospital Trauma Life Support, Trauma Evaluation and Management, and Advanced Trauma Operative Management, are applied according to a patient's current condition. However, the ideal strategy remains unclear. With permissive hypotension, also known as hypotensive resuscitation, fluid administration is less aggressive. The available models of permissive hypotension are based on hypotheses in hypovolemic physiology and restricted clinical trials in animals. Before these models can be used in patients, randomized, controlled clinical trials are necessary.

  18. [Prophylaxis and treatment of arterial hypotension during caesarean with spinal anaesthesia].

    PubMed

    Arias, J; Lacassie, H J

    2013-11-01

    Caesarean section is one of the most common surgical procedures worldwide. Arterial hypotension is the most prevalent adverse effect after spinal anaesthesia. Various methods have been used to prevent or treat hypotension. Since there is no treatment 100% effective by itself, a multimodal management is required to achieve an optimum balance and avoidance of hemodynamic imbalance. Strategies to avoid this side effect are analyzed on the basis of the best evidence available so far, summarized as mechanical factors, anesthetics, fluids and vasopressors. After spinal anaesthesia for caesarean section, the best strategy available for prevention of hypotension appears to be the combination of crystalloids along with an alpha 1 agonist vasopressor. Copyright © 2012 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

  19. Defining hypotension in moderate to severely injured trauma patients: raising the bar for the elderly.

    PubMed

    Edwards, Meghan; Ley, Eric; Mirocha, James; Hadjibashi, Anoushiravan Amini; Margulies, Daniel R; Salim, Ali

    2010-10-01

    Hypotension, defined as systolic blood pressure less than 90 mm Hg, is recognized as a sign of hemorrhagic shock and is a validated prognostic indicator. The definition of hypotension, particularly in the elderly population, deserves attention. We hypothesized that the systolic blood pressure associated with increased mortality resulting from hemorrhagic shock increases with increasing age. The Los Angeles County Trauma Database was queried for all moderate to severely injured patients without major head injuries admitted between 1998 and 2005. Several fit statistic analyses were performed for each systolic blood pressure from 50 to 180 mm Hg to identify the model that most accurately defined hypotension for three age groups. The optimal definition of hypotension for each group was determined from the best fit model. A total of 24,438 patients were analyzed. The optimal definition of hypotension was systolic blood pressure of 100 mm Hg for patients 20 to 49 years, 120 mm Hg for patients 50 to 69 years, and 140 mm Hg for patients 70 years and older. The optimal systolic blood pressure for improved mortality in hemorrhagic shock increases significantly with increasing age. Elderly trauma patients without major head injuries should be considered hypotensive for systolic blood pressure less than 140 mm Hg.

  20. Orthostatic hypotension as an unusual clinical manifestation of pheochromocytoma: a case report.

    PubMed

    Bortnik, Miriam; Occhetta, Eraldo; Marino, Paolo

    2008-08-01

    Pheochromocytoma is a rare endocrine tumor which can have a highly variable presentation related to increased catecholamine secretion. We report the case of a 74-year-old man in whom recurrent episodes of syncope due to orthostatic hypotension were the only clinical manifestations of this challenging entity. Diagnosis of pheochromocytoma was achieved by biochemical test samples and computed tomography scans. Surgical excision of the tumor resulted in clinical improvement with normalization of catecholamine concentrations and no more episodes of orthostatic hypotension during a follow-up of 24 months. Although rare, pheochromocytoma may frequently cause disorders of orthostatic tolerance; because of its meaningful implications, screening for this entity should be considered in case of recurrent syncopal episodes due to new-onset orthostatic hypotension.

  1. Influence of mianserin on the activity of some hypotensive drugs in spontaneously hypertensive rats.

    PubMed

    Górska, Dorota; Andrzejczak, Dariusz

    2003-01-01

    Mianserin might be an alternative drug in patients with depression accompanied by hypertension because of its effectiveness and lack of side effects in the circulatory system. However, a few studies reported in literature show influence of the drug on blood pressure. We investigate interactions between mianserin and commonly used hypotensive drugs (propranolol, enalapril and prazosin) in spontaneously hypertensive rats (SHR). The experiments were performed in two experimental designs: a single administration of both mianserin and a hypotensive drug, and repeated administration of mianserin with a single administration of a hypotensive drug. Arterial blood pressure was measured by bloodless method with manometer made by LETICA. A single administration of mianserin caused a statistically significant decrease in systolic, diastolic and mean blood pressure in the 60th minute of observation and intensified hypotensive effect of prazosin. However, long-term administration of mianserin in SHR rats had no significant influence on arterial blood pressure. Chronic and single administration of mianserin with propranolol or enalapril did not influence the circulatory system. A long-term administration of mianserin intensified the hypotensive effect of prazosin. This interaction might suggest possibility of dangerous complications in the treatment of humans with this drug combination.

  2. L-dihydroxyphenylserine (Droxidopa): a new therapy for neurogenic orthostatic hypotension: the US experience.

    PubMed

    Kaufmann, Horacio

    2008-03-01

    Neurogenic orthostatic hypotension results from failure to release norepinephrine, the neurotransmitter of sympathetic postganglionic neurons, appropriately upon standing. In double blind, cross over, placebo controlled trials, administration of droxidopa, a synthetic amino acid that is decarboxylated to norepinephrine by the enzyme L: -aromatic amino acid decarboxylase increases standing blood pressure, ameliorates symptoms of orthostatic hypotension and improves standing ability in patients with neurogenic orthostatic hypotension due to degenerative autonomic disorders. The pressor effect results from conversion of droxidopa to norepinephrine outside the central nervous system both in neural and non-neural tissue. This mechanism of action makes droxidopa effective in patients with central and peripheral autonomic disorders.

  3. Neurogenic orthostatic hypotension: a double-blind, placebo-controlled study with midodrine

    NASA Technical Reports Server (NTRS)

    Jankovic, J.; Gilden, J. L.; Hiner, B. C.; Kaufmann, H.; Brown, D. C.; Coghlan, C. H.; Rubin, M.; Fouad-Tarazi, F. M.

    1993-01-01

    PURPOSE: To investigate the efficacy and safety of midodrine for treatment of patients with orthostatic hypotension due to autonomic failure. PATIENTS: Ninety-seven patients with orthostatic hypotension were randomized in a 4-week, double-blinded, placebo-controlled study with a 1-week placebo run-in period. Patients ranged in age from 22 to 86 years (mean: 61 years). METHODS: After a 1-week run-in phase, either placebo or midodrine at a dose of 2.5 mg, 5 mg, or 10 mg was administered three times a day for 4 weeks. Both the placebo group and the 2.5-mg midodrine group received constant doses throughout the double-blind phase. The patients receiving 5 mg or 10 mg of midodrine were given doses that were increased at weekly intervals by 2.5-mg increments until the designated dose was reached. Efficacy evaluations were based on an improvement at 1-hour postdose in standing systolic blood pressure and in symptoms of orthostatic hypotension (syncope, dizziness/lightheadedness, weakness/fatigue, and low energy level). RESULTS: Midodrine (10 mg) increased standing systolic blood pressure by 22 mm Hg (28%, p < 0.001 versus placebo). Midodrine improved (p < 0.05) the following symptoms of orthostatic hypotension compared to placebo: dizziness/lightheadedness, weakness/fatigue, syncope, low energy level, impaired ability to stand, and feelings of depression. The overall side effects were mainly mild to moderate. One or more side effects were reported by 22% of the placebo group compared with 27% of the midodrine-treated group. Scalp pruritus/tingling, which was reported by 10 of 74 (13.5%) of the midodrine-treated patients, was most frequent. Other reported side effects included supine hypertension (8%) and feelings of urinary urgency (4%). CONCLUSION: We conclude that midodrine is an effective and well-tolerated treatment for moderate-to-severe orthostatic hypotension associated with autonomic failure.

  4. Exercise-induced decrease in insular cortex rCBF during postexercise hypotension.

    PubMed

    Lamb, Kala; Gallagher, Kevin; McColl, Roderick; Mathews, Dana; Querry, Ross; Williamson, Jon W

    2007-04-01

    The insular cortex (IC), a region of the brain involved in blood pressure (BP) modulation, shows decreases in regional cerebral blood flow (rCBF) during postexercise hypotension (PEH). To determine whether changes in IC neural activity were caused by prior exercise or by changes in BP, this investigation compared patterns of rCBF during periods of hypotension, which was induced by prior exercise (i.e., PEH) and sodium nitroprusside (SNP) infusion and a cold pressor (CP), to restore BP. Ten subjects were studied on three different days with randomly assigned conditions: i) resting baseline; ii) PEH; and iii) SNP-induced hypotension (matched to the PEH BP decrease). Data were collected for heart rate (HR) and mean BP, and rCBF was assessed using single-photon emission computed tomography (SPECT) as an index of brain activation. Using ANOVA across conditions, there were differences (P<0.05; mean +/- SD) from baseline during PEH for HR (+12 +/- 3 bpm) and mean BP (-8 +/- 2 mm Hg) and during SNP-induced hypotension (HR = +15 +/- 4 bpm; MBP = -9 +/- 2 mm Hg), with no differences between PEH and SNP. After exercise, there were decreases (P<0.05) in the leg sensorimotor area, anterior cingulate, and the right and left inferior thalamus, right inferior insula, and left anterior insular regions. During SNP-induced hypotension, there were significant increases in the right and left inferior thalamus and the right and left inferior anterior IC. CP during PEH increased BP and IC activity. Data show that reductions in IC neural activity are not caused by acute BP decreases. Findings suggest that exercise can lead to a temporary decrease in IC neural activity, which may be a significant neural factor contributing to PEH.

  5. Superoxide and Nitric Oxide Mechanisms in Traumatic Brain Injury and Hemorrhagic Hypotension.

    DTIC Science & Technology

    1999-12-01

    DISTRIBUTION CODE 13. ABSTRACT (Maximum 200 Words) Traumatic brain injury (TBI) renders the brain vulnerable to secondary ischemia and poor outcome...cerebral blood flow (CBF) and renders the brain vulnerable to secondary ischemia. There is clinical evidence that hypotension contributes to poor...without TBI. These data indicate that even moderate TBI renders the brain sensitive to ischemic injury during relative mild levels of hypotension that

  6. Increased diuresis, renal vascular reactivity, and blood pressure levels in young rats fed high sodium, moderately high fructose, or their association: a comparative evaluation.

    PubMed

    Da Silva, Rita de Cássia Vilhena A F; de Souza, Priscila; da Silva-Santos, José Eduardo

    2016-12-01

    Excessive intakes of sodium or fructose have been described as risk factors for hypertension. We hypothesized that even a moderately high fructose diet (6% fructose), either alone or in combination with high sodium (4% NaCl), may impair diuresis and renal and systemic vascular reactivity, contributing to the onset of high blood pressure in rats. Male Wistar rats were fed chow containing 4% NaCl (HS), 6% fructose (MHF), or both 4% NaCl and 6% fructose (HSMHF) for 6 weeks and had their diuresis, plasma creatinine, vascular reactivity of perfused kidneys and systemic arterial pressure evaluated. We found no differences in augmented diuresis among animals given HS, MHF, or HSMHF diets. After 6 weeks both the HS and HSMHF groups had increased weight in their left kidneys, but only the HSMHF group showed augmented plasma creatinine. The effects of phenylephrine on renal vascular perfusion pressure were similarly enhanced in kidneys from the HS, MHF, and HSMHF groups, but not on the systemic arterial pressure. Although when evaluated in anesthetized rats, only the HSMHF group presented augmented blood pressure, evaluation in conscious animals revealed that both the MHF and HSMHF diets, but not the HS alone, were able to induce tachycardia and hypertension. In conclusion, a MHF diet containing 6% fructose was enough to render the renal vascular bed hyperreactive to phenylephrine and to induce both hypertension and tachycardia. The combination of 6% fructose with 4% NaCl led to plasma accumulation of creatinine and accelerated the development of tachycardia.

  7. Automatic adaptive system dialysis for hemodialysis-associated hypotension and intolerance: a noncontrolled multicenter trial.

    PubMed

    Colì, Luigi; La Manna, Gaetano; Comai, Giorgia; Ursino, Mauro; Ricci, Davide; Piccari, Matteo; Locatelli, Francesco; Di Filippo, Salvatore; Cristinelli, Luciano; Bacchi, Massimo; Balducci, Alessandro; Aucella, Filippo; Panichi, Vincenzo; Ferrandello, Francesco Paolo; Tarchini, Renzo; Lambertini, Domenica; Mura, Carlo; Marinangeli, Giancarlo; Di Loreto, Ermanno; Quarello, Francesco; Forneris, Giacomo; Tancredi, Maurizio; Morosetti, Massimo; Palombo, Giuditta; Di Luca, Marina; Martello, Mauro; Emiliani, Giuseppe; Bellazzi, Roberto; Stefoni, Sergio

    2011-07-01

    Hemodialysis is complicated by a high incidence of intradialytic hypotension and disequilibrium symptoms caused by hypovolemia and a decrease in extracellular osmolarity. Automatic adaptive system dialysis (AASD) is a proprietary dialysis system that provides automated elaboration of dialysate and ultrafiltration profiles based on the prescribed decrease in body weight and sodium content. A noncontrolled (single arm), multicenter, prospective, clinical trial. 55 patients with intradialytic hypotension or disequilibrium syndrome in 15 dialysis units were studied over a 1-month interval using standard treatment (642 sessions) followed by 6 months using AASD (2,376 sessions). AASD (bicarbonate dialysis with dialysate sodium concentration and ultrafiltration rate profiles determined by the automated procedure). Primary and major secondary outcomes were the frequency of intradialytic hypotension and symptoms (hypotensive events, headache, nausea, vomiting, and cramps), respectively. More stable intradialytic systolic and diastolic blood pressures with lower heart rate were found using AASD compared with standard treatment. Sessions complicated by hypotension decreased from 58.7% ± 7.3% to 0.9% ± 0.6% (P < 0.001). The incidence of other disequilibrium syndrome symptoms was lower in patients receiving AASD. There were no differences in end-session body weight, interdialytic weight gain, or presession natremia between the standard and AASD treatment periods. A noncontrolled (single arm) study, no crossover from AASD to standard treatment. This study shows the long-term clinical efficacy of AASD for intradialytic hypotension and disequilibrium symptoms in a large number of patients and dialysis sessions. Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  8. Effects of hemorrhagic hypotension on tyrosine concentrations in rat spinal cord and plasma

    NASA Technical Reports Server (NTRS)

    Conlay, L. A.; Maher, T. J.; Roberts, C. H.; Wurtman, R. J.

    1988-01-01

    Tyrosine is the precursor for catecholamine neurotransmitters. When catecholamine-containing neurons are physiologically active (as sympathoadrenal cells are in hypotension), tyrosine administration increases catecholamine synthesis and release. Since hypotension can alter plasma amino acid composition, the effects of an acute hypotensive insult on tyrosine concentrations in plasma and spinal cord were examined. Rats were cannulated and bled until the systolic blood pressure was 50 mmHg, or were kept normotensive for 1 h. Tyrosine and other large neutral amino acids (LNAA) known to compete with tyrosine for brain uptake were assayed in plasma and spinal cord. The rate at which intra-arterial (H-3)tyrosine disappeared from the plasma was also estimated in hemorrhaged and control rats. In plasma of hemorrhaged animals, both the tyrosine concentration and the tyrosine/LNAA ratio was elevated; moreover, the disappearance of (H-3)tyrosine was slowed. Tyrosine concentrations also increased in spinal cords of hemorrhaged-hypotensive rats when compared to normotensive controls. Changes in plasma amino acid patterns may thus influence spinal cord concentrations of amino acid precursors for neurotransmitters during the stress of hemorrhagic shock.

  9. More hypotension in patients taking antihypertensives preoperatively during shoulder surgery in the beach chair position.

    PubMed

    Trentman, Terrence L; Fassett, Sharon L; Thomas, Justin K; Noble, Brie N; Renfree, Kevin J; Hattrup, Steven J

    2011-11-01

    Hypotension is common in patients undergoing surgery in the sitting position under general anesthesia, and the risk may be exacerbated by the use of antihypertensive drugs taken preoperatively. The purpose of this study was to compare hypotensive episodes in patients taking antihypertensive medications with normotensive patients during shoulder surgery in the beach chair position. Medical records of all patients undergoing shoulder arthroscopy during a 44-month period were reviewed retrospectively. The primary endpoint was the number of moderate hypotensive episodes (systolic blood pressure ≤ 85 mmHg) during the intraoperative period. Secondary endpoints included the frequency of vasopressor administration, total dose of vasopressors, and fluid administered. Values are expressed as mean (standard deviation). Of 384 patients who underwent shoulder surgery, 185 patients were taking no antihypertensive medication, and 199 were on at least one antihypertensive drug. The antihypertensive medication group had more intraoperative hypotensive episodes [1.7 (2.2) vs 1.2 (1.8); P = 0.01] and vasopressor administrations. Total dose of vasopressors and volume of fluids administered were similar between groups. The timing of the administration of angiotensin-converting enzyme inhibitors and of angiotensin receptor antagonists (≤ 10 hr vs > 10 hr before surgery) had no impact on intraoperative hypotension. Preoperative use of antihypertensive medication was associated with an increased incidence of intraoperative hypotension. Compared with normotensive patients, patients taking antihypertensive drugs preoperatively are expected to require vasopressors more often to maintain normal blood pressure.

  10. [How can we improve symptomatic hypotension in hemodialysis patients: cold dialysis vs isothermic dialysis].

    PubMed

    Ramos, R; Soto, C; Mestres, R; Jara, J; Zequera, H; Merello, J I; Moreso, F

    2007-01-01

    Symptomatic hypotension is the most frequent acute complication affecting patients during chronic hemodialysis treatment sessions. Many reports have demonstrated that the use of cool dialysate has a protective effect on blood pressure during hemodialysis treatments. In the present study, we investigated whether preventing the hyperthermic response had favourable effects on hemodynamic stability during the hemodialysis procedure while affording good tolerance to patients. We investigated the effect of thermal control of dialysate on hemodynamic stability in hypotension-prone patients in our center. Patients were eligible for the study if they had symptomatic hypotensive episodes (> 3/12session/ month) during the screening phase. The study was designed with two phases for the same selected patients and two treatment arms, each phase lasting 4 weeks. In the first phase, we adjusted dialysate temperature on 36 masculineC for 12 sessions (cold dialysis) and in the second phase we used a device allowing the regulation of thermal balance (Blood Temperature Monitor; Fresenius Medical Care, Bad Homberg, Germany), that keep body temperature unchanged (isothermic dialysis). Nine HD patients were enrolled and completed the study. During the screening phase the mean ultrafiltration was 4 1% of dry weight, and blood pressure decreased from 9916 to 8016 mm Hg (p<0.001). In 5.01.7 sessions of 12 treatments were complicated by hypotension. In the first and second phase we observed a decrease of complicated treatments with symptomatic hypotension (5.01.7 versus 2.71.6 y 2.81.7; p<0.01). Both procedures: Cold dialysis and Isothermic dialysis was well tolerated by patients. Results show that active control of body temperature can significantly improve intradialytic tolerance in hypotension-prone patients.

  11. Hypotension and Bradycardia Caused by the Inadvertent Ingestion of Rhododendron japonicum.

    PubMed

    Koda, Ryo; Honma, Miho; Suzuki, Kazuo; Kasai, Akio; Takeda, Tetsuro; Narita, Ichiei; Yoshida, Kazukiyo

    2016-01-01

    A 61-year-old man was transferred to our hospital with the complaints of dizziness, severe nausea and abdominal discomfort after consuming approximately 50 g of the flowers of Rhododendron japonicum. On admission, hypotension and sinus bradycardia were evident. Symptoms including hypotension and bradycardia completely recovered within 12 hours following normal saline infusion and intravenous atropine. The ingestion of certain types of Rhododendron species can cause intoxication, referred to as "mad honey poisoning", due to the action of grayanotoxins. This is the first local case of acute intoxication caused by Rhododendron japonicum.

  12. Orthostatic hypotension: pathophysiology, assessment, treatment and the paradox of supine hypertension.

    PubMed

    Chisholm, Peter; Anpalahan, Mahesan

    2017-04-01

    Both hypertension and orthostatic hypotension (OH) are strongly age-associated and are common management problems in older people. However, unlike hypertension, management of OH has unique challenges with few well-established treatments. Not infrequently, they both coexist, further compounding the management. This review provides comprehensive information on OH, including pathophysiology, diagnostic workup and treatment, with a view to provide a practical guide to its management. Special references are made to patients with supine hypertension and postprandial hypotension and older hypertensive patients. © 2016 Royal Australasian College of Physicians.

  13. Orthostatic hypotension and overall mortality in 1050 older patients of the outpatient comprehensive geriatric assessment unit.

    PubMed

    Freud, Tamar; Punchik, Boris; Kagan, Ella; Barzak, Alex; Press, Yan

    2018-03-02

    Orthostatic hypotension is a common problem in individuals aged ≥65 years. Its association with mortality is not clear. The aim of the present study was to evaluate associations between orthostatic hypotension and overall mortality in a sample of individuals aged ≥65 years who were seen at the Outpatient Comprehensive Geriatric Assessment Unit, Clalit Health Services, Beer-Sheva, Israel. Individuals who were evaluated in the Outpatient Comprehensive Geriatric Assessment Unit between January 2005 and December 2015, and who had data on orthostatic hypotension were included in the study. The database included sociodemographic characteristics, body mass index, functional and cognitive state, geriatric syndromes reached over the course of the assessment, and comorbidity. Data on mortality were also collected. The study sample included 1050 people, of whom 626 underwent comprehensive geriatric assessment and 424 underwent geriatric consultation. The mean age was 77.3 ± 5.4 years and 35.7% were men. Orthostatic hypotension was diagnosed in 294 patients (28.0%). In univariate analysis, orthostatic hypotension was associated with overall mortality only in patients aged 65-75 years (HR 1.5, 95% CI 1.07-2.2), but in the multivariate model this association disappeared. In older frail patients, orthostatic hypotension was not an independent risk factor for overall mortality. Geriatr Gerontol Int 2018; ••: ••-••. © 2018 Japan Geriatrics Society.

  14. Postural headache in marfan syndrome associated with spinal cysts and liquor hypotension.

    PubMed

    Voermans, N C; Dijk, K G J van; Bos, M M; Geus-Oei, L-F de; Verrips, A; Lindert, E J van

    2009-08-01

    We here report a 13-year-old Marfan patient who suffered from severe, medication-resistant, intermittent headache, which was provoked when getting into an upright position and immediately relieved by lying down or after intravenous rehydration. The postural benefit and the sudden relief after intravenous hydration suggested (intermittent) intracranial hypotension, although a normal opening pressure on lumbar punction was observed and no cerebrospinal fluid (CSF) leakage was identified. Imaging studies revealed severe dural ectasia at lumbosacral level, and two intradural cysts and two extradural presacral cysts were detected. Most likely, altered hydrodynamics in intra- and extracranial spinal meningeal cysts caused intermittent CSF hypotension above these cysts, resulting in intermittent intracranial hypotension. Surgical marsupialisation of the intradural cysts proved to be effective. This resulted in a significant reduction of the headache during the clinical follow-up of eight years. Georg Thieme Verlag KG Stuttgart New York.

  15. Anesthesia information management system-based near real-time decision support to manage intraoperative hypotension and hypertension.

    PubMed

    Nair, Bala G; Horibe, Mayumi; Newman, Shu-Fang; Wu, Wei-Ying; Peterson, Gene N; Schwid, Howard A

    2014-01-01

    Intraoperative hypotension and hypertension are associated with adverse clinical outcomes and morbidity. Clinical decision support mediated through an anesthesia information management system (AIMS) has been shown to improve quality of care. We hypothesized that an AIMS-based clinical decision support system could be used to improve management of intraoperative hypotension and hypertension. A near real-time AIMS-based decision support module, Smart Anesthesia Manager (SAM), was used to detect selected scenarios contributing to hypotension and hypertension. Specifically, hypotension (systolic blood pressure <80 mm Hg) with a concurrent high concentration (>1.25 minimum alveolar concentration [MAC]) of inhaled drug and hypertension (systolic blood pressure >160 mm Hg) with concurrent phenylephrine infusion were detected, and anesthesia providers were notified via "pop-up" computer screen messages. AIMS data were retrospectively analyzed to evaluate the effect of SAM notification messages on hypotensive and hypertensive episodes. For anesthetic cases 12 months before (N = 16913) and after (N = 17132) institution of SAM messages, the median duration of hypotensive episodes with concurrent high MAC decreased with notifications (Mann Whitney rank sum test, P = 0.031). However, the reduction in the median duration of hypertensive episodes with concurrent phenylephrine infusion was not significant (P = 0.47). The frequency of prolonged episodes that lasted >6 minutes (sampling period of SAM), represented in terms of the number of cases with episodes per 100 surgical cases (or percentage occurrence), declined with notifications for both hypotension with >1.25 MAC inhaled drug episodes (δ = -0.26% [confidence interval, -0.38% to -0.11%], P < 0.001) and hypertension with phenylephrine infusion episodes (δ = -0.92% [confidence interval, -1.79% to -0.04%], P = 0.035). For hypotensive events, the anesthesia providers reduced the inhaled drug concentrations to <1.25 MAC 81% of

  16. Deliberate fingolimod overdose presenting with delayed hypotension and bradycardia responsive to atropine.

    PubMed

    Stephenson, M; Wong, A; Rotella, J A; Crump, N; Kerr, F; Greene, S L

    2014-06-01

    Fingolimod is an immunomodulating agent used in multiple sclerosis (MS). It is a sphingosine-1-phosphate (S1P) receptor agonist prescribed for relapsing forms of MS to delay onset of physical disability. As fingolimod is known to cause first-dose bradycardia, telemetry is recommended for the first 6 h post-dose. We present the first reported case of deliberate fingolimod overdose requiring atropine administration for bradycardia and hemodynamic instability. A 33-year-old woman ingested 14 mg of fingolimod and 2 g of phenoxymethylpenicillin. After presenting to the emergency department 19 h later, she was initially hemodynamically stable (heart rate (HR) 60, blood pressure (BP) 113/89 mmHg). Two hours later, she then developed bradycardia (HR 48) and hypotension (87/57 mmHg). Despite intravenous fluids, stabilisation was only achieved after administration of atropine (300 μg). She was then admitted to the intensive care unit (ICU) for further monitoring where another episode of bradycardia and hypotension required atropine. She was monitored in the ICU for 48 h and then discharged on day 5 with no further episodes. Fingolimod is known to cause bradycardia in the first 6 h post first therapeutic dose. Following intentional overdose, onset of bradycardia occurred at 21 h post-ingestion and was associated with hypotension. Atropine was successful in treating bradycardia and associated hypotension.

  17. Atomoxetine for Orthostatic Hypotension in an Elderly Patient Over 10 Weeks: A Case Report.

    PubMed

    Hale, Genevieve M; Brenner, Michael

    2015-09-01

    Several nonpharmacologic strategies for orthostatic hypotension exist including avoiding large carbohydrate-rich meals; limiting alcohol consumption; maintaining adequate hydration; adding salt to foods; and using compression stockings, tilt-table exercises, or abdominal binders. If these fail, however, only limited evidence-based pharmacologic treatment options are available including the use of fludrocortisone, midodrine, pyridostigmine, and droxidopa as well as pseudoephedrine, ocetreotide, and atomoxetine. This report discusses a case of atomoxetine use for 10 weeks in an elderly patient with primary orthostatic hypotension. An 84-year-old man with long-standing primary orthostatic hypotension presented to our ambulatory cardiology pharmacotherapy clinic after several unsuccessful pharmacologic therapies including fludrocortisone, midodrine, and pyridostigmine. Nonpharmacologic strategies were also implemented. Atomoxetine was initiated, and the patient showed gradual improvements in symptoms and blood pressure control over the course of 10 weeks. Our data suggest that low-dose atomoxetine is an effective and safe agent for symptom improvement and blood pressure control in elderly patients with primary orthostatic hypotension. © 2015 Pharmacotherapy Publications, Inc.

  18. Effect of hemorrhage on cardiac output, vasopressin, aldosterone, and diuresis during immersion in men

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Simanonok, K.; Bernauer, E. M.; Wade, C. E.; Keil, L. C.

    1992-01-01

    The purpose of this research was to test the hypotesis that a reduction in blood volume would attenuate or eliminate immersion-induced increases in cardiac output (Q(sub co)) and urine excretion, and to investigate accompanying vasoactive and fluid-electrolyte hormonal responses. Eight men (19-23 yr) were supine during a 2-hr control period in air, and then sat for 5-hr test periods in air at 20 C (dry control, DC); water at 34.5 C (wet control, WC); and water (34.5 C) after hemorrhage (WH) of 14.8 plus or minus 0.3 percent of their blood volume. Blood volume was -11.6 plus or minus 0.6 percent at immersion (time 0). Mean (bar-X hrs 1-5) Q(sub co) was unchanged in WC (5.3 plus or minus 0.01 l/min) and in WH (4.5 plus or minus 0.1 l/min), but decreased (P less than 0.05) in DC to 3.6 plus or minus 0.1 l/min. Mean urine excretion rates were 1.0 plus or minus 0.2 ml/min for DC and 1.1 plus or minus 0.2 ml/min for WH; both were lower (P less than 0.05) than that for WC of 2.0 plus or minus 0.4 ml/min. Plasma (Na+) and (Osm) were unchanged in all experiments. Mean plasma vasopressin (PVP) (bar-X hrs 1-5) was 1.1 plus or minus 0.1 pg/ml in WC, and higher (P less than 0.05) in DC (2.1 plus or minus 0.2 pg/ml)and WH (2.1 plus or minus 0.1 pg/ml); it was unchanged during air and water test periods. Thus, hemorrhage attenuated the immersion-induced increase in Q(sub co), eliminated the WC diuresis, maintained plasma renin activity and PVP at DC levels and did not change immersion-induced aldosterone suppression; the osmotic diuresis during control immersion is apparently not due to either aldosterone suppression or vasopressin suppression.

  19. Forced diuresis with matched hydration in reducing acute kidney injury during transcatheter aortic valve implantation (Reduce-AKI): study protocol for a randomized sham-controlled trial.

    PubMed

    Arbel, Yaron; Ben-Assa, Eyal; Halkin, Amir; Keren, Gad; Schwartz, Arie Lorin; Havakuk, Ofer; Leshem-Rubinow, Eran; Konigstein, Maayan; Steinvil, Arie; Abramowitz, Yigal; Finkelstein, Ariel; Banai, Shmuel

    2014-07-02

    Acute kidney injury (AKI) is observed in up to 41% of patients undergoing transcatheter aortic valve implantation (TAVI) and is associated with increased risk for mortality. The aim of the present study is to evaluate whether furosemide-induced diuresis with matched isotonic intravenous hydration using the RenalGuard system reduces AKI in patients undergoing TAVI. Reduce-AKI is a randomized sham-controlled study designed to examine the effect of an automated matched hydration system in the prevention of AKI in patients undergoing TAVI. Patients will be randomized in a 1:1 fashion to the RenalGuard system (active group) versus non-matched saline infusion (sham-controlled group). Both arms receive standard overnight saline infusion and N-acetyl cysteine before the procedure. The Reduce-AKI trial will investigate whether the use of automated forced diuresis with matched saline infusion is an effective therapeutic tool to reduce the occurrence of AKI in patients undergoing TAVI. Clinicaltrials.gov: NCT01866800, 30 April 30 2013.

  20. Gallic acid, a phenolic compound isolated from Mimosa bimucronata (DC.) Kuntze leaves, induces diuresis and saluresis in rats.

    PubMed

    Schlickmann, Fabile; Boeing, Thaise; Mariano, Luisa Nathália Bolda; da Silva, Rita de Cássia Melo Vilhena de Andrade Fonseca; da Silva, Luisa Mota; de Andrade, Sérgio Faloni; de Souza, Priscila; Cechinel-Filho, Valdir

    2018-06-01

    Although present in the leaves of Mimosa bimucronata (DC.) and many other medicinal plants commonly used to augment urinary volume excretion, the effects of gallic acid as a diuretic agent remain to be studied. Wistar rats were orally treated with vehicle, hydrochlorothiazide, or gallic acid. The effects of gallic acid in the presence of hydrochlorothiazide, furosemide, amiloride, L-NAME, atropine, and indomethacin were also investigated. Diuretic index, pH, conductivity, and electrolyte excretion were evaluated at the end of the experiment (after 8 or 24 h). Gallic acid induced diuretic and saluretic (Na + and Cl - ) effects, without interfering with K + excretion, when orally given to female and male rats at a dose of 3 mg/kg. These effects were associated with increased creatinine and conductivity values while pH was unaffected by any of the treatments. Plasma Na + , K + , and Cl - levels were not affected by any of the acute treatments. The combination with hydrochlorothiazide or furosemide was unable to intensify the effects of gallic acid when compared with the response obtained with each drug alone. On the other hand, the treatment with amiloride plus gallic acid amplified both diuresis and saluresis, besides to a marked potassium-sparing effect. Its diuretic action was significantly prevented in the presence of indomethacin, a cyclooxygenase inhibitor, but not with the pretreatments with L-NAME or atropine. Although several biological activities have already been described for gallic acid, this is the first study demonstrating its potential as a diuretic agent.

  1. Intraoperative bradycardia and hypotension associated with timolol and pilocarpine eye drops.

    PubMed

    Mishra, P; Calvey, T N; Williams, N E; Murray, G R

    1983-09-01

    A 69-yr-old man, who was concurrently being treated with pilocarpine nitrate and timolol maleate eye drops, developed a bradycardia and became hypotensive during halothane anaesthesia. Both timolol and pilocarpine were subsequently identified in a 24-h collection of urine. Timolol (but not pilocarpine) was detected in a sample of plasma removed during surgery; the plasma concentration of timolol (2.6 ng ml-1) was consistent with partial beta-adrenoceptor blockade. It is postulated that this action may have been enhanced during halothane anaesthesia with resultant bradycardia and hypotension. Pilocarpine may have had a contributory effect.

  2. Adverse Drug Reactions for Medicines Newly Approved in Japan from 1999 to 2013: Hypertension and Hypotension.

    PubMed

    Nagayama, Takashi; Nishida, Minoru; Hizue, Masanori; Ogino, Yamato; Fujiyoshi, Masato

    2016-04-01

    In this survey, the correlation between adverse drug reactions (ADRs) in human and animal toxicities was investigated for 393 medicines which were approved in Japan from September 1999 to March 2013. ADRs were collected from each Japanese package insert. Comparable animal toxicities with ADRs were collected by thorough investigation of common technical documents. The results of this survey show that hypertension and/or hypotension were mainly observed in medicines affecting the central nervous system. Hypertension was also observed in antipyretics, analgesics, anti-inflammatory agents, vasoconstrictors and agents using antibody. Concordance between human ADRs and animal toxicities was analysed. True-positive rate for hypertension and hypotension is 0.29 and 0.52, respectively. Positive likelihood ratio and inverse negative likelihood ratio are 1.98 and 1.21, respectively, in hypertension and 1.67 and 1.44, respectively, in hypotension. Concordance between human ADRs and animal toxicities is not so high in hypertension and hypotension. Identified mechanisms as on-target for hypertension and hypotension are 29.8% and 30.5%, respectively. More than half of the causative factors of hypertension and hypotension were unable to be elucidated. Our results show that the intake of medicines is often linked to blood pressure variations that are not predicted in animal toxicity studies. Improvement of drug development processes may be necessary to provide safer medicines because current animal toxicity studies are insufficient to predict all ADRs in human beings. © 2015 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  3. Dosage variability of topical ocular hypotensive products: a densitometric assessment.

    PubMed

    Gaynes, Bruce I; Singa, Ramesh M; Cao, Ying

    2009-02-01

    To ascertain consequence of variability in drop volume obtained from multiuse topical ocular hypotensive products in terms of uniformity of product dosage. Densitometric assessment of drop volume dispensed from 2 alternative bottle positions. All except one product demonstrated a statistically significant difference in drop volume when administered at either a 45-degree or 90-degree bottle angle (Student t test, P<0.001). Product-specific drop volume ranged from a nadir of 22.36 microL to a high of 53.54 microL depending on bottle angle of administration. Deviation in drop dose was directly proportional to variability in drop volume. Variability in per drop dosage was conspicuous among products with a coefficient of variation from 1.49% to 15.91%. In accordance with drop volume, all products demonstrated a statistically significant difference in drop dose at 45-degree versus 90-degree administration angles. Drop volume was found unrelated to drop uniformity (Spearman r=0.01987 and P=0.9463). Variability and lack of uniformity in drop dosage is clearly evident among select ocular hypotensive products and is related to angle of drop administration. Erratic dosage of topical ocular hypotensive therapy may contribute in part to therapeutic failure and/or toxicity.

  4. Nimodipine prevents memory impairment caused by nitroglycerin-induced hypotension in adult mice.

    PubMed

    Bekker, Alex; Haile, Michael; Li, Yong-Sheng; Galoyan, Samuel; Garcia, Edwardo; Quartermain, David; Kamer, Angela; Blanck, Thomas

    2009-12-01

    Hypotension and a resultant decrease in cerebral blood flow have been implicated in the development of cognitive dysfunction. We tested the hypothesis that nimodipine (NIMO) administered at the onset of nitroglycerin (NTG)-induced hypotension would preserve long-term associative memory. The passive avoidance (PA) paradigm was used to assess memory retention. For PA training, latencies (seconds) were recorded for entry from a suspended platform into a Plexiglas tube where a shock was automatically delivered. Latencies were recorded 48 h later for a testing trial. Ninety-six Swiss-Webster mice (30-35 g, 6-8 wk), were randomized into 6 groups 1) saline (control), 2) NTG immediately after learning, 3) NTG 3 h after learning, 4) NTG and NIMO, 5) vehicle, and 6) NIMO alone. The extent of hypotension and changes in brain tissue oxygenation (PbtO(2)) and in cerebral blood flow were studied in a separate group of animals. All groups exhibited similar training latencies (17.0 +/- 4.6 s). Mice subjected to hypotensive episodes showed a significant decrease in latency time (178 +/- 156 s) compared with those injected with saline, NTG + NIMO, or delayed NTG (580 +/- 81 s, 557 +/- 67 s, and 493 +/- 146 s, respectively). A Kruskal-Wallis 1-way analysis of variance indicated a significant difference among the 4 treatment groups (H = 15.34; P < 0.001). In a separate group of mice not subjected to behavioral studies, the same dose of NTG (n = 3) and NTG + NIMO (n = 3) caused mean arterial blood pressure to decrease from 85.9 +/- 3.8 mm Hg sem to 31.6 +/- 0.8 mm Hg sem and from 86.2 +/- 3.7 mm Hg sem to 32.6 +/- 0.2 mm Hg sem, respectively. Mean arterial blood pressure in mice treated with NIMO alone decreased from 88.1 +/- 3.8 mm Hg to 80.0 +/- 2.9 mm Hg. The intergroup difference was statistically significant (P < 0.05). PbtO(2) decreased from 51.7 +/- 4.5 mm Hg sem to 33.8 +/- 5.2 mm Hg sem in the NTG group and from 38.6 +/- 6.1 mm Hg sem to 25.4 +/- 2.0 mm Hg sem in the NTG

  5. Effects of L-threo-3,4-dihydroxyphenylserine on orthostatic hypotension in hemodialysis patients.

    PubMed

    Iida, Nobutoshi; Koshikawa, Syozo; Akizawa, Tadao; Tsubakihara, Yoshiharu; Marumo, Fumiaki; Akiba, Takashi; Kawaguchi, Yoshindo; Imada, Akio; Yamazaki, Chikao; Suzuki, Masashi

    2002-01-01

    Orthostatic hypotension (OH) is a serious complication observed in hemodialysis (HD) patients after HD as well as during the interdialytic period. L-Threo-3,4-dihydroxyphenylserine (L-DOPS) is a nonphysiological neutral amino acid that is directly converted to the neurotransmitter norepinephrine by aromatic L-amino acid decarboxylase. A placebo-controlled double-blind study for 4 consecutive weeks and a long-term study (24-52 weeks) were conducted to evaluate the efficacy of L-DOPS for OH after HD. The drug was administered orally 30 min before the start of each HD period in both studies. Doses of 400 mg of L-DOPS or placebo were given to HD patients with OH (45 and 41 patients, respectively) in the double-blind study, and doses of 200 or 400 mg of L-DOPS were given to 74 HD patients in the long-term study. In the double-blind study, L-DOPS significantly ameliorated subjective symptoms related to OH, including dizziness/light-headed feeling, and malaise, throughout the interdialytic period. For 19 patients with delayed-type OH, hypotension with the lowest blood pressure recorded 10 min after standing, the decrease in blood pressure was suppressed significantly after L-DOPS treatment (10 patients) as compared with the placebo-treated group (9 patients). In the long-term study, the efficacy of L-DOPS was not attenuated, and the marked fluctuations in the plasma L-DOPS and norepinephrine levels were not noted after long-term use, without increases in incidence or severity of adverse reactions. These results indicate that L-DOPS is effective for improving OH-related interdialytic subjective symptoms in HD patients after short-term as well as after long-term administration. Copyright 2002 S. Karger AG, Basel

  6. Pharmacological properties of 2-(2-chloro-p-toluidino)-2-imidazoline-nitrate (tolonidine), a new antihypertensive agent. III. Action on the secretions of the digestive tract and on the central nervous system, acute toxicity.

    PubMed

    Cosnier, D; Hache, J; Labrid, C; Streichenberger, G

    1975-01-01

    The pharmacological properties of 2-(2-chloro-p-toluidino)-2-imidazoline-nitrate (tolonidine) a new synthetic derivative of imidazoline are reported in a series of three successive articles. This compound has been shown to possess hypotensive and antihypertensive properties. After i.v. administration, the hypotensive phase was preceded by hypertension related to the potent direct alpha-sympatheticomimetic properties of the product. This pressor response, which was not seen after oral administration, was accompanied by a marked decrease in cardiac output and a significant increase in peripheral vascular resistance. The hypotensive action of the product was due to a drop in cardiac output probably reinforced by a decrease in vasoconstrictor sympathetic tone due to a central action. Whatever the route of administration, tolonidine slowed heart rate independently of blood pressure variations, due essentially to an increase in vagal tone. In studies of diuresis, liquid and salt loss were observed in the cat, not in the dog. At doses which induce a drop in blood pressure tolonidine did not produce a reduction in pilocarpine-induced salivary secretion and only partially inhibited gastric secretion. In the central nervous system, tolonidine produced a sedation which first appeared at doses having an antihypertensive effect but which was only fully apparent with increased doses. A decrease in the release of cerebral amines, serotonin and noradrenaline by tolonidine is proposed. Tolonidine was compared with three other antihypertensive agents: clonidine, which is structurally related, and guanethidine and mecamylamine, which are structurally unrelated and have a different mode of action. A close resemblance of the pharmacological properties of tolonidine and clonidine was established due to the chemical relationship between the two substances.

  7. Hydrocortisone administration for the treatment of refractory hypotension in critically ill newborns.

    PubMed

    Baker, C F W; Barks, J D E; Engmann, C; Vazquez, D M; Neal, C R; Schumacher, R E; Bhatt-Mehta, V

    2008-06-01

    The purpose of this observation was to evaluate the safety and efficacy of hydrocortisone (HC) for the treatment of refractory hypotension in term and preterm infants. A secondary purpose was to determine the utility of serum cortisol concentrations in predicting the response to treatment. This is a retrospective observational study of 117 infants treated with a standardized HC protocol for refractory hypotension. Refractory hypotension was defined as a mean arterial pressure (MAP) less than the gestational age (GA) despite a total inotrope dose of 20 microg per kg per min. Baseline serum cortisol concentrations were determined prior to treatment with stress dose HC. Treatment with HC increased the MAP at 2, 6, 12 and 24 h after initiation, decreased the total inotrope dose at 6, 12 and 24 h, and was associated with resolution of oliguria. There was no correlation between the pretreatment baseline cortisol concentration and GA, birth weight or the response to treatment. The incidence of grades III to IV intraventricular hemorrhage, periventricular leukomalacia, bacterial or fungal sepsis and spontaneous intestinal perforation (SIP) after HC treatment was similar to institutional historic controls prior to institution of this standardized HC protocol. HC treatment was associated with a rapid resolution of cardiovascular compromise. The incidence of significant side effects was similar to that in previously published reports, including a comparable incidence of SIP. On the basis of our results, measuring baseline serum cortisol concentration to guide the management of refractory hypotension is unwarranted.

  8. Hypotensive effects of ghrelin receptor agonists mediated through a novel receptor.

    PubMed

    Callaghan, Brid; Kosari, Samin; Pustovit, Ruslan V; Sartor, Daniela M; Ferens, Dorota; Ban, Kung; Baell, Jonathan; Nguyen, Trung V; Rivera, Leni R; Brock, James A; Furness, John B

    2014-03-01

    Some agonists of ghrelin receptors cause rapid decreases in BP. The mechanisms by which they cause hypotension and the pharmacology of the receptors are unknown. The effects of ligands of ghrelin receptors were investigated in rats in vivo, on isolated blood vessels and on cells transfected with the only molecularly defined ghrelin receptor, growth hormone secretagogue receptor 1a (GHSR1a). Three agonists of GHSR1a receptors, ulimorelin, capromorelin and CP464709, caused a rapid decrease in BP in the anaesthetized rat. The effect was not reduced by either of two GHSR1a antagonists, JMV2959 or YIL781, at doses that blocked effects on colorectal motility, in vivo. The rapid hypotension was not mimicked by ghrelin, unacylated ghrelin or the unacylated ghrelin receptor agonist, AZP531. The early hypotension preceded a decrease in sympathetic nerve activity. Early hypotension was not reduced by hexamethonium or by baroreceptor (sino-aortic) denervation. Ulimorelin also relaxed isolated segments of rat mesenteric artery, and, less potently, relaxed aorta segments. The vascular relaxation was not reduced by JMV2959 or YIL781. Ulimorelin, capromorelin and CP464709 activated GHSR1a in transfected HEK293 cells at nanomolar concentrations. JMV2959 and YIL781 both antagonized effects in these cells, with their pA2 values at the GHSR1a receptor being 6.55 and 7.84. Our results indicate a novel vascular receptor or receptors whose activation by ulimorelin, capromorelin and CP464709 lowered BP. This receptor is activated by low MW GHSR1a agonists, but is not activated by ghrelin. © 2013 The British Pharmacological Society.

  9. Hypotensive effects of ghrelin receptor agonists mediated through a novel receptor

    PubMed Central

    Callaghan, Brid; Kosari, Samin; Pustovit, Ruslan V; Sartor, Daniela M; Ferens, Dorota; Ban, Kung; Baell, Jonathan; Nguyen, Trung V; Rivera, Leni R; Brock, James A; Furness, John B

    2014-01-01

    BACKGROUND AND PURPOSE Some agonists of ghrelin receptors cause rapid decreases in BP. The mechanisms by which they cause hypotension and the pharmacology of the receptors are unknown. EXPERIMENTAL APPROACH The effects of ligands of ghrelin receptors were investigated in rats in vivo, on isolated blood vessels and on cells transfected with the only molecularly defined ghrelin receptor, growth hormone secretagogue receptor 1a (GHSR1a). KEY RESULTS Three agonists of GHSR1a receptors, ulimorelin, capromorelin and CP464709, caused a rapid decrease in BP in the anaesthetized rat. The effect was not reduced by either of two GHSR1a antagonists, JMV2959 or YIL781, at doses that blocked effects on colorectal motility, in vivo. The rapid hypotension was not mimicked by ghrelin, unacylated ghrelin or the unacylated ghrelin receptor agonist, AZP531. The early hypotension preceded a decrease in sympathetic nerve activity. Early hypotension was not reduced by hexamethonium or by baroreceptor (sino-aortic) denervation. Ulimorelin also relaxed isolated segments of rat mesenteric artery, and, less potently, relaxed aorta segments. The vascular relaxation was not reduced by JMV2959 or YIL781. Ulimorelin, capromorelin and CP464709 activated GHSR1a in transfected HEK293 cells at nanomolar concentrations. JMV2959 and YIL781 both antagonized effects in these cells, with their pA2 values at the GHSR1a receptor being 6.55 and 7.84. CONCLUSIONS AND IMPLICATIONS Our results indicate a novel vascular receptor or receptors whose activation by ulimorelin, capromorelin and CP464709 lowered BP. This receptor is activated by low MW GHSR1a agonists, but is not activated by ghrelin. PMID:24670149

  10. Idiopathic orthostatic hypotension treated with levodopa and MAO inhibitor: a preliminary report

    PubMed Central

    Sharpe, J.; Marquez-Julio, A.; Ashby, P.

    1972-01-01

    The clinical and pathophysiological features of a case of idiopathic orthostatic hypotension (Shy-Drager syndrome) are presented. Recent reports on the pathological findings in this condition indicate that there may be a defect in catecholamine synthesis in the pigmented brain stem nuclei and sympathetic ganglia similar to that in idiopathic parkinsonism. On this basis a new form of therapy using levodopa combined with MAO inhibition is derived. The results of a trial of this therapy, which produced improvements in both the hypotension and in the extrapyramidal features of the disease, are reported. PMID:5056115

  11. A nationwide survey of factors influencing adherence to ocular hypotensive eyedrops in Japan.

    PubMed

    Tsumura, Toyoaki; Kashiwagi, Kenji; Suzuki, Yasuyuki; Yoshikawa, Keiji; Suzumura, Hirotaka; Maeda, Toshine; Takeda, Ryuji; Saito, Hitomi; Araie, Makoto

    2018-01-12

    Few reports have investigated the status of adherence in Japan on a large scale. We aimed to investigate the status of adherence to topical glaucoma treatment and its associated factors. A nationwide survey was conducted as a prospective fashion. Participants in this survey were subjects with primary open-angle glaucoma, normal-tension glaucoma, or ocular hypertension or pseudoexfoliation glaucoma who had been prescribed anti-glaucoma ophthalmic eyedrops and whose ophthalmologist considered prescribing any fixed combination of ocular hypotensive eyedrops for the first time between 2011 and 2012. Subjects and their attending ophthalmologists independently completed a questionnaire by utilizing a fixed combination of ocular hypotensive eyedrops. A total of 1358 ophthalmologists from 1071 medical institutions participated in this survey. We registered 4430 subjects (2049 males and 2381 females). In total, data from 3853 subjects (87.6%) were analyzed after inclusion of subjects based on inclusion and exclusion criteria. Good adherence was defined as not forgetting instillation during the past week. Rates of good adherence reported by subjects and ophthalmologists were 72.4 and 78.5%, respectively (P < 0.0001). The consistency of adherence evaluation between subjects and ophthalmologists was moderate [kappa score 0.5025 (95% confidence interval 0.4740-0.5309)]. Significant factors associated with adherence were size of clinic, age, gender, number of types of ocular hypotensive eyedrops, ease of instillation, preferred number of eyedrops, preferred frequency of instillation of eyedrops, and knowledge of glaucoma. Adherence to ocular hypotensive eyedrops among Japanese subjects was relatively good. Concordance of adherence between subjects' reports and ophthalmologists' responses was moderate. Size of clinic, number of types of ocular hypotensive eyedrops, ease of instillation, preferred number of eyedrops, preferred frequency of instillation of eyedrops, and knowledge

  12. Subclinical decelerations during developing hypotension in preterm fetal sheep after acute on chronic lipopolysaccharide exposure

    PubMed Central

    Lear, Christopher A.; Davidson, Joanne O.; Galinsky, Robert; Yuill, Caroline A.; Wassink, Guido; Booth, Lindsea C.; Drury, Paul P.; Bennet, Laura; Gunn, Alistair J.

    2015-01-01

    Subclinical (shallow) heart rate decelerations occur during neonatal sepsis, but there is limited information on their relationship with hypotension or whether they occur before birth. We examined whether subclinical decelerations, a fall in fetal heart rate (FHR) that remained above 100 bpm, were associated with hypotension in preterm fetal sheep exposed to lipopolysaccharide (LPS). Chronically-instrumented fetal sheep at 0.7 gestation received continuous low-dose LPS infusions (n = 15, 100 ng/kg over 24 h, followed by 250 ng/kg/24 h for 96 h) or saline (n = 8). Boluses of 1 μg LPS or saline were given at 48 and 72 h. FHR variability (FHRV) was calculated, and sample asymmetry was used to assess the severity and frequency of decelerations. Low-dose LPS infusion did not affect FHR. After the first LPS bolus, 7 fetuses remained normotensive, while 8 developed hypotension (a fall in mean arterial blood pressure of ≥5 mmHg). Developing hypotension was associated with subclinical decelerations, with a corresponding increase in sample asymmetry and FHRV (p < 0.05). The second LPS bolus was associated with similar but attenuated changes in FHR and blood pressure (p < 0.05). In conclusion, subclinical decelerations are not consistently seen during prenatal exposure to LPS, but may be a useful marker of developing inflammation-related hypotension before birth. PMID:26537688

  13. Opportunities for Web-based Drug Repositioning: Searching for Potential Antihypertensive Agents with Hypotension Adverse Events.

    PubMed

    Wang, Kejian; Wan, Mei; Wang, Rui-Sheng; Weng, Zuquan

    2016-04-01

    Drug repositioning refers to the process of developing new indications for existing drugs. As a phenotypic indicator of drug response in humans, clinical side effects may provide straightforward signals and unique opportunities for drug repositioning. We aimed to identify drugs frequently associated with hypotension adverse reactions (ie, the opposite condition of hypertension), which could be potential candidates as antihypertensive agents. We systematically searched the electronic records of the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) through the openFDA platform to assess the association between hypotension incidence and antihypertensive therapeutic effect regarding a list of 683 drugs. Statistical analysis of FAERS data demonstrated that those drugs frequently co-occurring with hypotension events were more likely to have antihypertensive activity. Ranked by the statistical significance of frequent hypotension reporting, the well-known antihypertensive drugs were effectively distinguished from others (with an area under the receiver operating characteristic curve > 0.80 and a normalized discounted cumulative gain of 0.77). In addition, we found a series of antihypertensive agents (particularly drugs originally developed for treating nervous system diseases) among the drugs with top significant reporting, suggesting the good potential of Web-based and data-driven drug repositioning. We found several candidate agents among the hypotension-related drugs on our list that may be redirected for lowering blood pressure. More important, we showed that a pharmacovigilance system could alternatively be used to identify antihypertensive agents and sustainably create opportunities for drug repositioning.

  14. Histopathological analysis of spontaneous large necrosis of adrenal pheochromocytoma manifested as acute attacks of alternating hypertension and hypotension: a case report.

    PubMed

    Ohara, Nobumasa; Uemura, Yasuyuki; Mezaki, Naomi; Kimura, Keita; Kaneko, Masanori; Kuwano, Hirohiko; Ebe, Katsuya; Fujita, Toshio; Komeyama, Takeshi; Usuda, Hiroyuki; Yamazaki, Yuto; Maekawa, Takashi; Sasano, Hironobu; Kaneko, Kenzo; Kamoi, Kyuzi

    2016-10-12

    Pheochromocytomas are rare catecholamine-producing neuroendocrine tumors. Hypertension secondary to pheochromocytoma is often paroxysmal, and patients occasionally present with sudden attacks of alternating hypertension and hypotension. Spontaneous, extensive necrosis within the tumor that is associated with catecholamine crisis is an infrequent complication of adrenal pheochromocytoma, but its pathogenesis remains unclear. A 69-year-old Japanese man developed acute-onset episodic headaches, palpitations, and chest pains. During the episodes, both marked fluctuations in blood pressure (ranging from 40/25 to 300/160 mmHg) and high plasma levels of catecholamines were found simultaneously. Radiological findings indicated a 4-cm left adrenal pheochromocytoma. These episodic symptoms disappeared within 2 weeks with normalization of plasma catecholamine levels. Two months later, the patient underwent adrenalectomy. Microscopic examinations revealed pheocromocytoma with a large central area of coagulative necrosis. The necrotic material was immunohistochemically positive for chromogranin A. Granulation tissue was adjacent to the necrotic area, accompanied by numerous hemosiderin-laden macrophages and histiocytes with vascular proliferation. Viable tumor cells, detected along the periphery of the tumor, demonstrated pyknosis, and the Ki-67 labeling index was 2 % in the hot spot. No embolus or thrombus formation was found in the resected specimen harboring the whole tumor. The Pheochromocytoma of the Adrenal gland Scaled Score was 2 out of 20. The patient's postoperative course was unremarkable for > 7 years. Presumed causal factors for the extensive necrosis of adrenal pheochromocytoma in previously reported cases include hemorrhage into the tumor, hypotension induced by a phentolamine administration, embolic infarction, high intracapsular pressure due to malignant growth of the tumor, and catecholamine-induced vasoconstriction. In the present case, histopathological

  15. Effect of discontinuation of antihypertensive medication on orthostatic hypotension in older persons with mild cognitive impairment: the DANTE Study Leiden.

    PubMed

    Moonen, Justine E F; Foster-Dingley, Jessica C; de Ruijter, Wouter; van der Grond, Jeroen; de Craen, Anton J M; van der Mast, Roos C

    2016-03-01

    the relationship between antihypertensive medication and orthostatic hypotension in older persons remains ambiguous, due to conflicting observational evidence and lack of data of clinical trials. to assess the effect of discontinuation of antihypertensive medication on orthostatic hypotension in older persons with mild cognitive impairment. a total of 162 participants with orthostatic hypotension were selected from the Discontinuation of Antihypertensive Treatment in Elderly people (DANTE) Study. This randomised clinical trial included community-dwelling participants aged ≥75 years, with mild cognitive impairment, using antihypertensive medication and without serious cardiovascular disease. Participants were randomised to discontinuation or continuation of antihypertensive treatment (ratio 1:1). Orthostatic hypotension was defined as a drop of at least 20 mmHg in systolic blood pressure and/or 10 mmHg in diastolic blood pressure on standing from a seated position. Outcome was the absence of orthostatic hypotension at 4-month follow-up. Relative risks (RR) were calculated by intention-to-treat and per-protocol analyses. at follow-up, according to intention-to-treat analyses, of the 86 persons assigned to discontinuation of antihypertensive medication, 43 (50%) were free from orthostatic hypotension, compared with 29 (38%) of the 76 persons assigned to continuation of medication [RR 1.31 (95% confidence interval (CI) 0.92-1.87); P = 0.13]. Per-protocol analysis showed that recovery from orthostatic hypotension was significantly higher in persons who completely discontinued all antihypertensive medication (61%) compared with the continuation group (38%) [RR 1.60 (95% CI 1.10-2.31); P = 0.01]. in older persons with mild cognitive impairment and orthostatic hypotension receiving antihypertensive medication, discontinuation of antihypertensive medication may increase the probability of recovery from orthostatic hypotension. © The Author 2016. Published by Oxford

  16. Overlap of Post-obstructive Diuresis and Unmasked Diabetes Insipidus in a Case of IgG4-related Retroperitoneal Fibrosis and Tuberoinfundibular Hypophysitis: A Case Report and Review of the Literature

    PubMed Central

    Sasaki Yatabe, Midori; Watanabe, Kimio; Hayashi, Yoshimitsu; Yatabe, Junichi; Morimoto, Satoshi; Ichihara, Atsuhiro; Nakayama, Masaaki; Watanabe, Tsuyoshi

    2017-01-01

    The clinical picture of IgG4-related disease (IgG4-RD) is diverse because various organs can be affected. We describe the case of a 56-year-old man with acute renal failure and tuberoinfundibular hypophysitis due to IgG4-RD. Steroid therapy lowered the serum IgG4 level and ameliorated renal dysfunction, bilateral hydronephrosis and retroperitoneal fibrosis. However, polyuria from post-obstructive diuresis and unmasked central diabetes insipidus ensued. The patient's polyuria continued despite the administration of a therapeutic dose of glucocorticoid; the patient's pituitary swelling and anterior pituitary dysfunction were partially ameliorated. The pituitary swelling recurred seven months later. In patients with IgG4-RD, the manifestation of polyuria after steroid therapy should prompt suspicion of post-obstructive diuresis and the unmasking of central diabetes insipidus. PMID:28049999

  17. Overlap of Post-obstructive Diuresis and Unmasked Diabetes Insipidus in a Case of IgG4-related Retroperitoneal Fibrosis and Tuberoinfundibular Hypophysitis: A Case Report and Review of the Literature.

    PubMed

    Sasaki Yatabe, Midori; Watanabe, Kimio; Hayashi, Yoshimitsu; Yatabe, Junichi; Morimoto, Satoshi; Ichihara, Atsuhiro; Nakayama, Masaaki; Watanabe, Tsuyoshi

    The clinical picture of IgG4-related disease (IgG4-RD) is diverse because various organs can be affected. We describe the case of a 56-year-old man with acute renal failure and tuberoinfundibular hypophysitis due to IgG4-RD. Steroid therapy lowered the serum IgG4 level and ameliorated renal dysfunction, bilateral hydronephrosis and retroperitoneal fibrosis. However, polyuria from post-obstructive diuresis and unmasked central diabetes insipidus ensued. The patient's polyuria continued despite the administration of a therapeutic dose of glucocorticoid; the patient's pituitary swelling and anterior pituitary dysfunction were partially ameliorated. The pituitary swelling recurred seven months later. In patients with IgG4-RD, the manifestation of polyuria after steroid therapy should prompt suspicion of post-obstructive diuresis and the unmasking of central diabetes insipidus.

  18. Forced diuresis with matched hydration in reducing acute kidney injury during transcatheter aortic valve implantation (Reduce-AKI): study protocol for a randomized sham-controlled trial

    PubMed Central

    2014-01-01

    Background Acute kidney injury (AKI) is observed in up to 41% of patients undergoing transcatheter aortic valve implantation (TAVI) and is associated with increased risk for mortality. The aim of the present study is to evaluate whether furosemide-induced diuresis with matched isotonic intravenous hydration using the RenalGuard system reduces AKI in patients undergoing TAVI. Methods/Design Reduce-AKI is a randomized sham-controlled study designed to examine the effect of an automated matched hydration system in the prevention of AKI in patients undergoing TAVI. Patients will be randomized in a 1:1 fashion to the RenalGuard system (active group) versus non-matched saline infusion (sham-controlled group). Both arms receive standard overnight saline infusion and N-acetyl cysteine before the procedure. Discussion The Reduce-AKI trial will investigate whether the use of automated forced diuresis with matched saline infusion is an effective therapeutic tool to reduce the occurrence of AKI in patients undergoing TAVI. Trial registration Clinicaltrials.gov: NCT01866800, 30 April 30 2013. PMID:24986373

  19. Report on 50 cases of severe acute hypotension at donor plasmaphereses: treatment and course.

    PubMed

    Evers, Josef; Schreiber, George B; Taborski, Uwe

    2017-05-29

    This paper reports our experience in 50 cases with severe hypotensive reactions at plasma donations (synonymous with donor plasmaphereses). Plasma donors who developed a severe acute hypotensive reaction at donor plasmapheresis, and were treated by placing the donor in the Trendelenburg position and rapid infusion of 1,000 mL saline were investigated. Plasmaphereses were performed with the Haemonetics® plasma collecting system 2 (PCS2). The results were analyzed using Excel. We observed 50 severe hypotensive reactions in plasma donors. The average systolic and diastolic blood pressures (SBP, DBP) were 128/75 mmHg - and heart rates were 78 beats/min (B/M) before plasmaphereses, 83/56 mmHg - 60 B/M at the event, and after treatment 119/71 mmHg - 69 B/M at the time of discharge. The volume of collected plasma was 602 ± 240 mL including anticoagulant (AC). The time until the event was 45 ± 20 minutes. With treatment 49 ± 18 minutes after the event all plasma donors had normal blood pressures and heart rates and could safely leave the center. Treatment by placing the donor in the Trendelenburg position and rapid infusion of 1,000 mL saline appears to be an effective procedure for resolving severe acute hypotension associated with donor plasmaphereses.

  20. The organizational structure of an intensive care unit influences treatment of hypotension among critically ill patients: A retrospective cohort study

    PubMed Central

    Boone, M. Dustin; Massa, Jennifer; Mueller, Ariel; Jinadasa, Sayuri P; Lee, Joon; Kothari, Rishi; Scott, Daniel J.; Callahan, Julie; Celi, Leo Anthony; Hacker, Michele R.

    2016-01-01

    Purpose Prior studies report that weekend admission to an intensive care unit is associated with increased mortality, potentially attributed to the organizational structure of the unit. This study aims to determine whether treatment of hypotension, a risk factor for mortality, differs according to level of staffing. Methods Using the Multiparameter Intelligent Monitoring in Intensive Care database, we conducted a retrospective study of patients admitted to an intensive care unit at Beth Israel Deaconess Medical Center who experienced one or more episodes of hypotension. Episode(s) were categorized according to the staffing level, defined as high during weekday daytime (7am–7pm) and low during weekends or nighttime (7pm–7am). Results Patients with a hypotensive event on a weekend were less likely to be treated compared to those that occurred during the weekday daytime (p=0.02). No association between weekday daytime versus weekday nighttime staffing levels and treatment of hypotension was found (RR 1.02; 95% CI 0.98–1.07). Conclusion Patients with a hypotensive event on a weekend were less likely to be treated than patients with an event during high-staffing periods. No association between weekday nighttime staffing and hypotension treatment was observed. We conclude that treatment of a hypotensive episode relies on more than solely staffing levels. PMID:26975737

  1. [Gastric dynamics analysis of TEAS combined SNP induced general anesthesia when controlled hypotension dropped to 60% of the MAP baseline].

    PubMed

    Zhang, Le-Le; Fang, Jian-Qiao; Shao, Xiao; Lian, Lin-Li; Yu, Xiao-Jing; Dong, Zhen-Hua; Mo, Ya-Di

    2015-01-01

    To observe the effect of gastric dynamics by transcutaneous electrical acupoint stimulation (TEAS) combined general anesthesia when controlled hypotension dropped to 60% of the mean arterial prenssure (MAP) baseline, and to provide experimental evidence for organ protection in clinical controlled hypotension. Eighteen male beagles were randomly divided into three groups, the general anesthesia group (blank), the general anesthesia induced controlled hypotension group (control), and the general anesthesia combined TEAS induced controlled hypotension group (experiment), 6 in each group. Controlled hypotension was performed in the latter two groups with isoflurane inhalation and intravenous injection of sodium nitroprusside (SNP). The mean arterial pressure (MAP) was lowered to 60% of the MAP baseline and kept for 60 min. Controlled hypotension was not performed in Beagles of the control group. For Beagles in the experiment group, TEAS [2/100 Hz, (4 ± 1) mA] was applied to bilateral Hegu (LI4), Quchi (LI11), Zusanli (ST36), and Sanyinjiao (SP6) from stable physiological conditions to the end of maintaining stages. Changes of EGG frequencies and EGG amplitudes were monitored. Serum levels of gastrin (GAS) and motilin (MTL) were also detected at corresponding time points during and after experiment. As for the pressure control effect of TEAS combined general anesthesia in the controlled hypotension, during the process of controlled hypotension (T1-T4), MAP levels of two controlled pressure groups remained relatively stable, and were kept at 60% of the MAP baseline. When the blood pressure dropped to the target low MAP and maintained at 60 min (T1-T4), EGG amplitudes of Beagles in all the three groups showed decreasing tendency. But it was more obviously lower than its basic level in the control group (P <0.05), while it was not obviously decreased in the experiment group (P < 0.05). EGG frequencies of Beagles in all the three groups showed no obvious change during this

  2. Dynamic regulation of heart rate during acute hypotension: new insight into baroreflex function

    NASA Technical Reports Server (NTRS)

    Zhang, R.; Behbehani, K.; Crandall, C. G.; Zuckerman, J. H.; Levine, B. D.; Blomqvist, C. G. (Principal Investigator)

    2001-01-01

    To examine the dynamic properties of baroreflex function, we measured beat-to-beat changes in arterial blood pressure (ABP) and heart rate (HR) during acute hypotension induced by thigh cuff deflation in 10 healthy subjects under supine resting conditions and during progressive lower body negative pressure (LBNP). The quantitative, temporal relationship between ABP and HR was fitted by a second-order autoregressive (AR) model. The frequency response was evaluated by transfer function analysis. Results: HR changes during acute hypotension appear to be controlled by an ABP error signal between baseline and induced hypotension. The quantitative relationship between changes in ABP and HR is characterized by a second-order AR model with a pure time delay of 0.75 s containing low-pass filter properties. During LBNP, the change in HR/change in ABP during induced hypotension significantly decreased, as did the numerator coefficients of the AR model and transfer function gain. Conclusions: 1) Beat-to-beat HR responses to dynamic changes in ABP may be controlled by an error signal rather than directional changes in pressure, suggesting a "set point" mechanism in short-term ABP control. 2) The quantitative relationship between dynamic changes in ABP and HR can be described by a second-order AR model with a pure time delay. 3) The ability of the baroreflex to evoke a HR response to transient changes in pressure was reduced during LBNP, which was due primarily to a reduction of the static gain of the baroreflex.

  3. The Treatment of Primary Orthostatic Hypotension.

    PubMed

    Hale, Genevieve M; Valdes, Jose; Brenner, Michael

    2017-05-01

    To review the efficacy and safety of pharmacological and nonpharmacological strategies used to treat primary orthostatic hypotension (OH). A literature review using PubMed and MEDLINE databases searching hypotension, non-pharmacological therapy, midodrine, droxidopa, pyridostigmine, fludrocortisone, atomoxetine, pseudoephedrine, and octreotide was performed. Randomized or observational studies, cohorts, case series, or case reports written in English between January 1970 and November 2016 that assessed primary OH treatment in adult patients were evaluated. Based on the chosen criteria, it was found that OH patients make up approximately 15% of all syncope patients, predominantly as a result of cardiovascular or neurological insults, or offending medication. Nonpharmacological strategies are the primary treatment, such as discontinuing offending medications, switching medication administration to bedtime, avoiding large carbohydrate-rich meals, limiting alcohol, maintaining adequate hydration, adding salt to diet, and so on. If these fail, pharmacotherapy can help ameliorate symptoms, including midodrine, droxidopa, fludrocortisone, pyridostigmine, atomoxetine, sympathomimetic agents, and octreotide. Midodrine and droxidopa possess the most evidence with respect to increasing blood pressure and alleviating symptoms. Pyridostigmine and fludrocortisone can be used in patients who fail to respond to these agents. Emerging evidence with low-dose atomoxetine is promising, especially in those with central autonomic failure, and may prove to be a viable alternative treatment option. Data surrounding other therapies such as sympathomimetic agents or octreotide are minimal. Medication management of primary OH should be guided by patient-specific factors, such as tolerability, adverse effects, and drug-drug and drug-disease interactions.

  4. [Intra-anesthetic arterial hypotension in elderly patients during emergency surgery: what are the risk factors?

    PubMed

    Boubacar Ba, El Hadji; Leye, Papa Alassane; Traoré, Mamadou Mour; Ndiaye, Pape Ibrahima; Gaye, Ibrahima; Bah, Mamadou Diawo; Fall, Mamadou Lamine; Diouf, Elisabeth

    2017-01-01

    Emergency anesthesia in elderly patients aged 65 years and older is complex. The occurrence of intraoperative incidents and arterial hypotension is conditioned by patients' initial health status and by the quality of intraoperative management. This study aimed to determine the incidence of intra-anesthetic arterial hypotension in elderly patients during emergency surgery and to assess the involvement of certain factors in its occurrence: age, sex, patient's history, ASA class, anesthetic technique. We conducted a retrospective descriptive and analytical study in the Emergency Surgery Department at the Aristide Le Dantec University Hospital from 1 March 2014 to 28 February 2015. We collected data from 210 patients out of 224 elderly patients aged 65 years and older undergoing emergency anesthesias (10.93%). Data of 101 men and 109 women were included in the analysis, of whom 64.3% had at least one defect. Patients' preoperative status was assessed using American Society of Anesthesiology (ASA) classification: 71% of patients were ASA class 1 and 2 and 29% were ASA class 3 and 4. Locoregional anesthesia was the most practiced anesthetic technique (56.7%). 28 patients (13.33%) had intra-anesthetic arterial hypotension, of whom 16 under general anesthesia and 12 under locoregional anesthesia. It was more frequent in patients with high ASA class and a little less frequent in patients with PAH and underlying heart disease. Arterial hypotension in elderly patients during emergency surgery exposes the subject to the risk of not negligible intraoperative hypotension, especially in patients with high ASA class. Prevention is based on adequate preoperative assessment and anesthetic management.

  5. Pulse Rate and Transit Time Analysis to Predict Hypotension Events After Spinal Anesthesia During Programmed Cesarean Labor.

    PubMed

    Bolea, Juan; Lázaro, Jesús; Gil, Eduardo; Rovira, Eva; Remartínez, José M; Laguna, Pablo; Pueyo, Esther; Navarro, Augusto; Bailón, Raquel

    2017-09-01

    Prophylactic treatment has been proved to reduce hypotension incidence after spinal anesthesia during cesarean labor. However, the use of pharmacological prophylaxis could carry out undesirable side-effects on mother and fetus. Thus, the prediction of hypotension becomes an important challenge. Hypotension events are hypothesized to be related to a malfunctioning of autonomic nervous system (ANS) regulation of blood pressure. In this work, ANS responses to positional changes of 51 pregnant women programmed for a cesarean labor were explored for hypotension prediction. Lateral and supine decubitus, and sitting position were considered while electrocardiographic and pulse photoplethysmographic signals were recorded. Features based on heart rate variability, pulse rate variability (PRV) and pulse transit time (PTT) analysis were used in a logistic regression classifier. The results showed that PRV irregularity changes, assessed by approximate entropy, from supine to lateral decubitus, and standard deviation of PTT in supine decubitus were found as the combination of features that achieved the best classification results sensitivity of 76%, specificity of 70% and accuracy of 72%, being normotensive the positive class. Peripheral regulation and blood pressure changes, measured by PRV and PTT analysis, could help to predict hypotension events reducing prophylactic side-effects in the low-risk population.

  6. Recurrence of non-cardiogenic pulmonary edema and sustained hypotension shock in cystic pheochromocytoma.

    PubMed

    Dai, Jin; Chen, Shen-Jie; Yang, Bing-Sheng; Lü, Shu-Min; Zhu, Min; Xu, Yi-Fei; Chen, Jie; Cai, Hong-Wen; Mao, Wei

    2017-05-01

    Pheochromocytoma is a rare neuroendocrine tumor which derives from chromaffin cells of the adrenal gland or relevant to sympathetic nerves and ganglia. The clinical features of pheochromocytoma are various. Paroxysmal episodes of serious hypertension, headache, palpitation, and diaphoresis are the typical manifestations (Bravo, 2004). Hypotension shock, pulmonary edema, and acute coronary syndrome induced by pheochromocytoma are uncommon (Malindretos et al., 2008; Batisse-Lignier et al., 2015). In this study, we present a rare case of cystic pheochromocytoma causing recurrent hypotension shock, non-cardiogenic pulmonary edema, and acute coronary syndrome, and the possible mechanisms are discussed.

  7. Droxidopa for orthostatic hypotension: a systematic review and meta-analysis.

    PubMed

    Strassheim, Victoria; Newton, Julia L; Tan, Maw Pin; Frith, James

    2016-10-01

    The systematic review and meta-analysis aims to determine the efficacy and safety of droxidopa in the treatment of orthostatic hypotension, following its recent approvals in the United States. MEDLINE, EMBASE, PubMed, Cochrane Controlled Trials Register, Web of Science, ProQuest, and the WHO Clinical Trials Registry were searched. Studies were included if they randomized adults with orthostatic hypotension to droxidopa or to control, and outcomes related to symptoms, daily activity, blood pressure, or adverse events. Data were extracted independently by two reviewers. Risk of bias was judged against the Cochrane risk of bias tool and quality of evidence measured using Grading of Recommendations Assessment, Development and Evaluation criteria. A fixed-effects model was used for pooled analysis. Of 224 identified records, four studies met eligibility, with a pooled sample size of 494. Study duration was between 1 and 8 weeks. Droxidopa was effective at reducing dizziness [mean difference -0.97 (95% confidence interval -1.51, -0.42)], overall symptoms [-0.52 (-0.98, -0.06)] and difficulty with activity [-0.86 (-1.34, -0.38)]. Droxidopa was also effective at improving standing SBP [3.9 (0.1, 7.69)]. Rates of adverse events were similar between droxidopa and control groups, including supine hypertension [odds ratio 1.93 (0.87, 4.25)]. Droxidopa is well tolerated and effective at reducing the symptoms associated with neurogenic orthostatic hypotension without increasing the risk of supine hypertension. PROSPERO ID CRD42015024612.

  8. Alanine increases blood pressure during hypotension

    NASA Technical Reports Server (NTRS)

    Conlay, L. A.; Maher, T. J.; Wurtman, R. J.

    1990-01-01

    The effect of L-alanine administration on blood pressure (BP) during haemorrhagic shock was investigated using anesthetized rats whose left carotid arteries were cannulated for BP measurement, blood removal, and drug administration. It was found that L-alanine, in doses of 10, 25, 50, 100, and 200 mg/kg, increased the systolic BP of hypotensive rats by 38 to 80 percent (while 100 mg/kg pyruvate increased BP by only 9.4 mmhg, not significantly different from saline). The results suggest that L-alanine might influence cardiovascular function.

  9. Minoxidil for severe hypertension after failure of other hypotensive drugs.

    PubMed Central

    Devine, B L; Fife, R; Trust, P M

    1977-01-01

    Forty-four patients with severe hypertension who were resistant to treatment with more conventional hypotensive drugs or could not tolerate the side effects were treated with minoxidil, a potent peripheral vasodilator. A beta-blocking drug and a diuretic were used routinely to control, respectively, the tachycardia and fluid retention caused by minoxidil. During treatment the outpatient supine blood pressure fell from a mean of 221/134 mm Hg to 162/98 mm Hg. Eleven patients required additional or alternative hypotensive agents before blood pressure was adequately controlled. Side effects were minor, although the invariable hirsuties caused by minoxidil was unacceptable to three women. The possibility of cardiotoxic effects, raised by early studies in dogs, has not been excluded, and therefore this drug should be used only in patients with severe hypertension. In such patients minoxidil appears to be most effective. PMID:902045

  10. Predicting the Occurrence of Hypotension in Stable Patients With Nonvariceal Upper Gastrointestinal Bleeding: Point-of-Care Lactate Testing.

    PubMed

    Ko, Byuk Sung; Kim, Won Young; Ryoo, Seung Mok; Ahn, Shin; Sohn, Chang Hwan; Seo, Dong Woo; Lee, Yoon-Seon; Lim, Kyoung Soo; Jung, Hwoon-Yong

    2015-11-01

    It is difficult to assess risk in normotensive patients with upper gastrointestinal bleeding. The aim of this study was to evaluate whether the initial lactate value can predict the in-hospital occurrence of hypotension in stable patients with acute nonvariceal upper gastrointestinal bleeding. Retrospective, observational, single-center study. Emergency department of a tertiary-care, university-affiliated hospital during a 5-year period. Medical records of 3,489 patients with acute upper gastrointestinal bleeding who were normotensive at presentation to the emergency department. We analyzed the ability of point-of-care testing of lactate at emergency department admission to predict hypotension development (defined as systolic blood pressure <90 mm Hg) within 24 hours after emergency department admission. None. Of the 1,003 patients with acute nonvariceal upper gastrointestinal bleeding, 157 patients experienced hypotension within 24 hours. Lactate was independently associated with hypotension development (odds ratio, 1.6; 95% CI, 1.4-1.7), and the risk of hypotension significantly increased as the lactate increased from 2.5-4.9 mmol/L (odds ratio, 2.2) to 5.0-7.4 mmol/L (odds ratio, 4.0) and to greater than or equal to 7.5 mmol/L (odds ratio, 39.2) (p<0.001). Lactate elevation (≥2.5 mmol/L) was associated with 90% specificity and an 84% negative predictive value for hypotension development. When the lactate levels were greater than 5.0 mmol/L, the specificity and negative predictive value increased to 98% and 87%, respectively. Point-of-care testing of lactate can predict in-hospital occurrence of hypotension in stable patients with acute nonvariceal upper gastrointestinal bleeding. However, subsequently, prospective validate research will be required to clarify this.

  11. Diagnosing and treating neurogenic orthostatic hypotension in primary care.

    PubMed

    Kuritzky, Louis; Espay, Alberto J; Gelblum, Jeffrey; Payne, Richard; Dietrich, Eric

    2015-01-01

    In response to a change in posture from supine or sitting to standing, autonomic reflexes normally maintain blood pressure (BP) by selective increases in arteriovenous resistance and by increased cardiac output, ensuring continued perfusion of the central nervous system. In neurogenic orthostatic hypotension (NOH), inadequate vasoconstriction and cardiac output cause BP to drop excessively, resulting in inadequate perfusion, with predictable symptoms such as dizziness, lightheadedness and falls. The condition may represent a central failure of baroreceptor signals to modulate cardiovascular function, a peripheral failure of norepinephrine release from cardiovascular sympathetic nerve endings, or both. Symptomatic patients may benefit from both non-pharmacologic and pharmacologic interventions. Among the latter, two pressor agents have been approved by the US Food and Drug Administration: the sympathomimetic prodrug midodrine, approved in 1996 for symptomatic orthostatic hypotension, and the norepinephrine prodrug droxidopa, approved in 2014, which is indicated for the treatment of symptomatic neurogenic orthostatic hypotension caused by primary autonomic failure (Parkinson's disease, multiple system atrophy and pure autonomic failure). A wide variety of off-label options also have been described (e.g. the synthetic mineralocorticoid fludrocortisone). Because pressor agents may promote supine hypertension, NOH management requires monitoring of supine BP and also lifestyle measures to minimize supine BP increases (e.g. head-of-bed elevation). However, NOH has been associated with cognitive impairment and increases a patient's risk of syncope and falls, with the potential for serious consequences. Hence, concerns about supine hypertension - for which the long-term prognosis in patients with NOH is yet to be established - must sometimes be balanced by the need to address a patient's immediate risks.

  12. Patients' choice of portable folding chairs to reduce symptoms of orthostatic hypotension

    NASA Technical Reports Server (NTRS)

    Smit, A. A.; Wieling, W.; Opfer-Gehrking, T. L.; van Emmerik-Levelt, H. M.; Low, P. A.

    1999-01-01

    Patients with neurogenic orthostatic hypotension may use portable folding chairs to prevent or reduce symptoms of low blood pressure. However, a concomitant movement disorder may limit the use of these chairs in daily living. In this prospective study, 13 patients with orthostatic hypotension, balance disturbance associated with motor disability, or both examined three commercially available portable folding chairs. A questionnaire was used to document the characteristics in chair design that were relevant for satisfactory use to these patients. Armrests, seat width, and an adjustable sitting height were found to be important features of a portable folding chair. One chair was selected by 11 of 13 patients to fit most needs.

  13. Maternal and anaesthesia-related risk factors and incidence of spinal anaesthesia-induced hypotension in elective caesarean section: A multinomial logistic regression.

    PubMed

    Fakherpour, Atousa; Ghaem, Haleh; Fattahi, Zeinabsadat; Zaree, Samaneh

    2018-01-01

    Although spinal anaesthesia (SA) is nowadays the preferred anaesthesia technique for caesarean section (CS), it is associated with considerable haemodynamic effects, such as maternal hypotension. This study aimed to evaluate a wide range of variables (related to parturient and anaesthesia techniques) associated with the incidence of different degrees of SA-induced hypotension during elective CS. This prospective study was conducted on 511 mother-infant pairs, in which the mother underwent elective CS under SA. The data were collected through preset proforma containing three parts related to the parturient, anaesthetic techniques and a table for recording maternal blood pressure. It was hypothesized that some maternal (such as age) and anaesthesia-related risk factors (such as block height) were associated with occurance of SA-induced hypotension during elective CS. The incidence of mild, moderate and severe hypotension was 20%, 35% and 40%, respectively. Eventually, ten risk factors were found to be associated with hypotension, including age >35 years, body mass index ≥25 kg/m 2 , 11-20 kg weight gain, gravidity ≥4, history of hypotension, baseline systolic blood pressure (SBP) <120 mmHg and baseline heart rate >100 beats/min in maternal modelling, fluid preloading ≥1000 ml, adding sufentanil to bupivacaine and sensory block height >T 4 in anaesthesia-related modelling ( P < 0.05). Age, body mass index, weight gain, gravidity, history of hypotension, baseline SBP and heart rate, fluid preloading, adding sufentanil to bupivacaine and sensory block hieght were the main risk factors identified in the study for SA-induced hypotension during CS.

  14. Hypovolemia-induced Orthostatic Hypotension Relates To Hypo-sympathetic Responsiveness

    NASA Technical Reports Server (NTRS)

    Meck, Janice V.

    2007-01-01

    We report a new model which uses hypovolemia to force humans into a hemodynamic state that is similar to that after spaceflight. This model can be used to test candidate countermeasures for postflight orthostatic hypotension and to identify crewmembers who will be most susceptible to that symptom on landing day.

  15. Early blood pressure, anti-hypotensive therapy and outcomes at 18 to 22 month corrected age in extremely preterm infants

    PubMed Central

    Batton, Beau; Li, Lei; Newman, Nancy S.; Das, Abhik; Watterberg, Kristi L.; Yoder, Bradley A.; Faix, Roger G.; Laughon, Matthew M.; Stoll, Barbara J.; Higgins, Rosemary D.; Walsh, Michele C.

    2016-01-01

    Objective Investigate relationships between early blood pressure (BP) changes, receipt of anti-hypotensive therapy, and 18 – 22 month corrected age (CA) outcomes for extremely preterm infants. Design Prospective observational study of infants 230/7 – 266/7 weeks gestational age (GA). Hourly BP values and anti-hypotensive therapy exposure in the first 24 hours were recorded. Four groups were defined: infants who did or did not receive anti-hypotensive therapy in whom BP did or did not rise at the expected rate (defined as an increase in the mean arterial BP of ≥5 mmHg/day). Random-intercept logistic modeling controlling for center clustering, GA, and illness severity was used to investigate the relationship between BP, anti-hypotensive therapies, and infant outcomes. Setting Sixteen academic centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Main Outcome Measures Death or neurodevelopmental impairment / developmental delay (NIDD) at 18 – 22 months CA. Results Of 367 infants, 203 (55%) received an anti-hypotensive therapy, 272 (74%) survived to discharge, and 331 (90%) had a known outcome at 18 – 22 months CA. With logistic regression, there was an increased risk of death/NIDD with anti-hypotensive therapy versus no treatment (odds ratio: 1.836, 95% confidence interval: 1.092 – 3.086), but not NIDD alone (odds ratio: 1.53, 95% confidence interval: 0.708 – 3.307). Conclusion Independent of early BP changes, anti-hypotensive therapy exposure was associated with an increased risk of death/NIDD at 18 to 22 months CA when controlling for risk factors known to affect survival and neurodevelopment. PMID:26567120

  16. Prediction of hypotension during spinal anesthesia for elective cesarean section by altered heart rate variability induced by postural change.

    PubMed

    Sakata, K; Yoshimura, N; Tanabe, K; Kito, K; Nagase, K; Iida, H

    2017-02-01

    Maternal hypotension is a common complication during cesarean section performed under spinal anesthesia. Changes in maternal heart rate with postural changes or values of heart rate variability have been reported to predict hypotension. Therefore, we hypothesized that changes in heart rate variability due to postural changes can predict hypotension. A total of 45 women scheduled to undergo cesarean section under spinal anesthesia were enrolled. A postural change test was performed the day before cesarean section. The ratio of the power of low and high frequency components contributing to heart rate variability was assessed in the order of supine, left lateral, and supine. Patients who exhibited a ⩾two-fold increase in the low-to-high frequency ratio when moving to supine from the lateral position were assigned to the postural change test-positive group. According to the findings of the postural change test, patients were assigned to the positive (n=22) and negative (n=23) groups, respectively. Hypotension occurred in 35/45 patients, of whom 21 (60%) were in the positive group and 14 (40%) were in the negative group. The incidence of hypotension was greater in the positive group (P<0.01). The total dose of ephedrine was greater in the positive group (15±11 vs. 7±7mg, P=0.005). The area under the receiver operating characteristic curve was 0.76 for the postural change test as a predictor of hypotension. The postural change test with heart rate variability analysis may be used to predict the risk of hypotension during spinal anesthesia for cesarean section. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Vasorelaxing Action of the Kynurenine Metabolite, Xanthurenic Acid: The Missing Link in Endotoxin-Induced Hypotension?

    PubMed

    Fazio, Francesco; Carrizzo, Albino; Lionetto, Luana; Damato, Antonio; Capocci, Luca; Ambrosio, Mariateresa; Battaglia, Giuseppe; Bruno, Valeria; Madonna, Michele; Simmaco, Maurizio; Nicoletti, Ferdinando; Vecchione, Carmine

    2017-01-01

    The kynurenine pathway of tryptophan metabolism is activated by pro-inflammatory cytokines. L-kynurenine, an upstream metabolite of the pathway, acts as a putative endothelium-derived relaxing factor, and has been hypothesized to play a causative role in the pathophysiology of inflammation-induced hypotension. Here, we show that xanthurenic acid (XA), the transamination product of 3-hydroxykynurenine, is more efficacious than L-kynurenine in causing relaxation of a resistance artery, but fails to relax pre-contracted aortic rings. In the mesenteric artery, XA enhanced activating phosphorylation of endothelial nitric oxide synthase (NOS), and the relaxing action of XA was abrogated by pharmacological inhibition of NOS and endothelial-derived hyperpolarizing factor. Systemic injection of XA reduced blood pressure in mice, and serum levels of XA increased by several fold in response to a pulse with the endotoxin, lipopolysaccharide (LPS). LPS-induced hypotension in mice was prevented by pre-treatment with the kynurenine monooxygenase (KMO) inhibitor, Ro-618048, which lowered serum levels of XA but enhanced serum levels of L-kynurenine. UPF 648, another KMO inhibitor, could also abrogate LPS-induced hypotension. Our data identify XA as a novel vasoactive compound and suggest that formation of XA is a key event in the pathophysiology of inflammation-induced hypotension.

  18. Vasorelaxing Action of the Kynurenine Metabolite, Xanthurenic Acid: The Missing Link in Endotoxin-Induced Hypotension?

    PubMed Central

    Fazio, Francesco; Carrizzo, Albino; Lionetto, Luana; Damato, Antonio; Capocci, Luca; Ambrosio, Mariateresa; Battaglia, Giuseppe; Bruno, Valeria; Madonna, Michele; Simmaco, Maurizio; Nicoletti, Ferdinando; Vecchione, Carmine

    2017-01-01

    The kynurenine pathway of tryptophan metabolism is activated by pro-inflammatory cytokines. L-kynurenine, an upstream metabolite of the pathway, acts as a putative endothelium-derived relaxing factor, and has been hypothesized to play a causative role in the pathophysiology of inflammation-induced hypotension. Here, we show that xanthurenic acid (XA), the transamination product of 3-hydroxykynurenine, is more efficacious than L-kynurenine in causing relaxation of a resistance artery, but fails to relax pre-contracted aortic rings. In the mesenteric artery, XA enhanced activating phosphorylation of endothelial nitric oxide synthase (NOS), and the relaxing action of XA was abrogated by pharmacological inhibition of NOS and endothelial-derived hyperpolarizing factor. Systemic injection of XA reduced blood pressure in mice, and serum levels of XA increased by several fold in response to a pulse with the endotoxin, lipopolysaccharide (LPS). LPS-induced hypotension in mice was prevented by pre-treatment with the kynurenine monooxygenase (KMO) inhibitor, Ro-618048, which lowered serum levels of XA but enhanced serum levels of L-kynurenine. UPF 648, another KMO inhibitor, could also abrogate LPS-induced hypotension. Our data identify XA as a novel vasoactive compound and suggest that formation of XA is a key event in the pathophysiology of inflammation-induced hypotension. PMID:28507519

  19. Recurrence of non-cardiogenic pulmonary edema and sustained hypotension shock in cystic pheochromocytoma*#

    PubMed Central

    Dai, Jin; Chen, Shen-jie; Yang, Bing-sheng; Lü, Shu-min; Zhu, Min; Xu, Yi-fei; Chen, Jie; Cai, Hong-wen; Mao, Wei

    2017-01-01

    Pheochromocytoma is a rare neuroendocrine tumor which derives from chromaffin cells of the adrenal gland or relevant to sympathetic nerves and ganglia. The clinical features of pheochromocytoma are various. Paroxysmal episodes of serious hypertension, headache, palpitation, and diaphoresis are the typical manifestations (Bravo, 2004). Hypotension shock, pulmonary edema, and acute coronary syndrome induced by pheochromocytoma are uncommon (Malindretos et al., 2008; Batisse-Lignier et al., 2015). In this study, we present a rare case of cystic pheochromocytoma causing recurrent hypotension shock, non-cardiogenic pulmonary edema, and acute coronary syndrome, and the possible mechanisms are discussed. PMID:28471119

  20. Magnitude of Hypotension Based on Office and Ambulatory Blood Pressure Monitoring: Results From a Cohort of 5066 Treated Hypertensive Patients Aged 80 Years and Older.

    PubMed

    Divisón-Garrote, Juan A; Ruilope, Luis M; de la Sierra, Alejandro; de la Cruz, Juan J; Vinyoles, Ernest; Gorostidi, Manuel; Escobar-Cervantes, Carlos; Velilla-Zancada, Sonsoles M; Segura, Julián; Banegas, José R

    2017-05-01

    Elderly patients can be particularly susceptible to the adverse effects of excessive blood pressure (BP) lowering by antihypertensive treatment. The identification of hypotension is thus especially important. Ambulatory BP monitoring (ABPM) is a more accurate technique than office for classifying BP status. This study examined the prevalence of hypotension and associated demographic and clinical factors among very old treated hypertensive patients undergoing ABPM. Cross-sectional study in which 5066 patients aged 80 years and older with treated hypertension drawn from the Spanish ABPM Registry were included. Office BP and 24-hour ambulatory BP were determined using validated devices under standardized conditions. Based on previous studies, hypotension was defined as systolic/diastolic BP <110 and/or 70 mmHg with office measurement, <105 and/or 65 mmHg with daytime ABPM, <90 and/or 50 mmHg with nighttime ABPM, and <100 and/or 60 mmHg with 24-hour ABPM. Participants' mean age was 83.2 ± 3.1 years (64.4% women). Overall, 22.8% of patients had office hypotension, 33.7% daytime hypotension, 9.2% nighttime hypotension, and 20.5% 24-hour ABPM hypotension. Low diastolic BP values were responsible for 90% of cases of hypotension. In addition, 59.1% of the cases of hypotension detected by daytime ABPM did not correspond to hypotension according to office BP. The variables independently associated with office and ABPM hypotension were diabetes, coronary heart disease, and a higher number of antihypertensive medications. One in 3 very elderly treated hypertensive patients attended in usual clinical practice were potentially at risk of having hypotension according to daytime ABPM. More than half of them had masked hypotension; that is, they were not identified if relying on office BP alone. Thus, ABPM could be especially helpful for identifying ambulatory hypotension and avoiding overtreatment, in particular, in patients with diabetes, heart disease, or on

  1. Forewarning of hypotensive events using a Bayesian artificial neural network in neurocritical care.

    PubMed

    Donald, Rob; Howells, Tim; Piper, Ian; Enblad, P; Nilsson, P; Chambers, I; Gregson, B; Citerio, G; Kiening, K; Neumann, J; Ragauskas, A; Sahuquillo, J; Sinnott, R; Stell, A

    2018-05-24

    Traumatically brain injured (TBI) patients are at risk from secondary insults. Arterial hypotension, critically low blood pressure, is one of the most dangerous secondary insults and is related to poor outcome in patients. The overall aim of this study was to get proof of the concept that advanced statistical techniques (machine learning) are methods that are able to provide early warning of impending hypotensive events before they occur during neuro-critical care. A Bayesian artificial neural network (BANN) model predicting episodes of hypotension was developed using data from 104 patients selected from the BrainIT multi-center database. Arterial hypotension events were recorded and defined using the Edinburgh University Secondary Insult Grades (EUSIG) physiological adverse event scoring system. The BANN was trained on a random selection of 50% of the available patients (n = 52) and validated on the remaining cohort. A multi-center prospective pilot study (Phase 1, n = 30) was then conducted with the system running live in the clinical environment, followed by a second validation pilot study (Phase 2, n = 49). From these prospectively collected data, a final evaluation study was done on 69 of these patients with 10 patients excluded from the Phase 2 study because of insufficient or invalid data. Each data collection phase was a prospective non-interventional observational study conducted in a live clinical setting to test the data collection systems and the model performance. No prediction information was available to the clinical teams during a patient's stay in the ICU. The final cohort (n = 69), using a decision threshold of 0.4, and including false positive checks, gave a sensitivity of 39.3% (95% CI 32.9-46.1) and a specificity of 91.5% (95% CI 89.0-93.7). Using a decision threshold of 0.3, and false positive correction, gave a sensitivity of 46.6% (95% CI 40.1-53.2) and specificity of 85.6% (95% CI 82.3-88.8). With a decision threshold of 0

  2. Maternal and anaesthesia-related risk factors and incidence of spinal anaesthesia-induced hypotension in elective caesarean section: A multinomial logistic regression

    PubMed Central

    Fakherpour, Atousa; Ghaem, Haleh; Fattahi, Zeinabsadat; Zaree, Samaneh

    2018-01-01

    Background and Aims: Although spinal anaesthesia (SA) is nowadays the preferred anaesthesia technique for caesarean section (CS), it is associated with considerable haemodynamic effects, such as maternal hypotension. This study aimed to evaluate a wide range of variables (related to parturient and anaesthesia techniques) associated with the incidence of different degrees of SA-induced hypotension during elective CS. Methods: This prospective study was conducted on 511 mother–infant pairs, in which the mother underwent elective CS under SA. The data were collected through preset proforma containing three parts related to the parturient, anaesthetic techniques and a table for recording maternal blood pressure. It was hypothesized that some maternal (such as age) and anaesthesia-related risk factors (such as block height) were associated with occurance of SA-induced hypotension during elective CS. Results: The incidence of mild, moderate and severe hypotension was 20%, 35% and 40%, respectively. Eventually, ten risk factors were found to be associated with hypotension, including age >35 years, body mass index ≥25 kg/m2, 11–20 kg weight gain, gravidity ≥4, history of hypotension, baseline systolic blood pressure (SBP) <120 mmHg and baseline heart rate >100 beats/min in maternal modelling, fluid preloading ≥1000 ml, adding sufentanil to bupivacaine and sensory block height >T4in anaesthesia-related modelling (P < 0.05). Conclusion: Age, body mass index, weight gain, gravidity, history of hypotension, baseline SBP and heart rate, fluid preloading, adding sufentanil to bupivacaine and sensory block hieght were the main risk factors identified in the study for SA-induced hypotension during CS. PMID:29416149

  3. New developments in the management of neurogenic orthostatic hypotension.

    PubMed

    Biaggioni, Italo

    2014-11-01

    Orthostatic hypotension (OH) is defined as a sustained reduction of ≥ 20 mmHg systolic blood pressure or ≥ 10 mmHg diastolic blood pressure upon standing for ≤ 3 min. Orthostatic hypotension is commonly associated with hypertension, and its prevalence is highest in those with uncontrolled hypertension compared to those with controlled hypertension or normotensive community elderly subjects. Orthostatic hypotension can cause significant disability, with patients experiencing dizziness, lightheadedness or syncope, and other problems that potentially have a profound negative impact on activities of daily living that require standing or walking. Furthermore, OH increases the risk of falls and, importantly, is an independent risk factor of mortality. Despite its importance, there is a paucity of treatment options for this condition. Most of the advances in treatment options have relied on small studies of repurposed drugs done in patients with severe OH due to rare neurodegenerative conditions. Midodrine, an oral prodrug converted to the selective α1-adrenoceptor agonist desglymidodrine, was approved by the FDA for the treatment of OH in 1996. For almost two decades, no other pharmacotherapy was developed specifically for the treatment of OH until 2014, when droxidopa was approved by the FDA for the treatment of neurogenic OH associated with primary autonomic neuropathies including Parkinson disease, multiple system atrophy, and pure autonomic failure. These are neurodegenerative diseases ultimately characterized by failure of the autonomic nervous system to generate norepinephrine responses appropriate to postural challenge. Droxidopa is a synthetic amino acid that is converted to norepinephrine by dopa-decarboxylase, the same enzyme that converts levodopa into dopamine in the treatment of Parkinson disease. We will review this and other advances in the treatment of OH in an attempt to provide a practical guide to its management.

  4. Burr hole drainage for complicated spontaneous intracranial hypotension syndrome.

    PubMed

    Liu, Yu-Fang; Lin, Hung-Lin; Cho, Der-Yang; Chen, Chun-Chung; Lo, Yu-Chien; Chiou, Shang-Ming

    2008-09-01

    Spontaneous intracranial hypotension is a potentially severe condition that is caused by continuous cerebrospinal fluid leakage. Clinically, most patients have a benign course and the condition remits after conservative management. We report two consecutive patients who presented with acute expansion of subdural collection and disturbed consciousness. Both patients recovered completely after undergoing burr hole drainage.

  5. [Experimental study on ocular hypotensive efficacy of parenteral metoprolol].

    PubMed

    Onishchenko, A L; Kolbasko, A V; Safronova, M A; Tarash, O S; Dimaksyan, M V

    2015-01-01

    to evaluate ocular hypotensive efficacy of parenteral metoprolol in an experiment. A total of 3 series of experiments on 24 rabbits were performed. The first series involved a single subconjunctival injection of 0.3 mg of metoprolol in the right eye, while the left served as a control. During the second series the rabbits received 0.5 mg of metoprolol intramuscularly. The third series also implied a subconjunctival injection of 0.3 mg of metoprolol in the right eye, however, supplemented with timolol 0.5% instilled in the left. In all rabbits tonometry was performed before the injection and then in 30 min, 1, 2, 3, 6, 8, and 24 hours. Biomicroscopy and ophthalmoscopy were also performed before and 1, 3, and 7 days after the injection. The maximum reduction (down to 30% from the baseline) of intraocular pressure (IOP) was registered in intramuscular metoprolol rabbits. Subconjunctival metoprolol was associated with a faster and more pronounced decrease in IOP as compared to timolol instillations. In case of local or systemic parenteral administration the hypotensive effect of metoprolol lasts for more than a day.

  6. The effect of permissive hypotension in combined traumatic brain injury and blunt abdominal trauma: an experimental study in swines.

    PubMed

    Vrettos, T; Poimenidi, E; Athanasopoulos, P; Balasis, S; Karagiorgos, N; Siklis, T; Gatzounis, G; Fligkou, F

    2016-01-01

    Optimal hemodynamic resuscitation strategy of the trauma patient with uncontrolled hemorrhage and severe head injury in the pre-hospital setting remains a special challenge. Permissive hypotension prior to definite surgical haemostasis promotes coagulation, decreases blood loss and favors survival. However, hypotension is associated with poor outcome in severe head injury. The purpose of this experimental animal study was to assess the impact of permissive hypotension on survival, hemodynamic profile and brain oxygenation parameters before and/or after definite surgical haemostasis. Six-week-old pigs (n=12) underwent general anesthesia and brain injury was produced by the fluid percussion model. Animals were instrumented to measure hemodynamic parameters and cerebral blood flow. All animals (n=12) were subjected to laparotomy and a surgical knot was placed through the abdominal aorta wall. Uncontrolled hemorrhage was simulated by pulling out the intentionally left protruding free ends of the suture (goal MAP=30 mmHg). Animals were randomly divided into two groups; group A (n=6) was subjected to aggressive fluid resuscitation (goal SAP >80 mmHg) and group B (n=6) was left hypotensive (permissive hypotension). Animals who survived one hour of hypotensive shock underwent definite surgical haemostasis and were resuscitated for one hour. We measured survival, hemodynamic and brain oxygenation parameters at different time points before and after surgical haemostasis. All animals from Group A and 50% from Group B died before surgical haemostasis. In surviving animals (Group B, 50%, p=0.033), MAP, CO, rCBF, SjO2 and AVDO2 were restored to pre-procedural levels. Permissive hypotension by delaying fluid resuscitation up to definite surgical haemostasis improves survival, hemodynamics and allows restoration of cerebral oxygenation in severe head injury.

  7. Increase in gastric pH reduces hypotensive effect of oral sodium nitrite in rats.

    PubMed

    Pinheiro, Lucas C; Montenegro, Marcelo F; Amaral, Jefferson H; Ferreira, Graziele C; Oliveira, Alisson M; Tanus-Santos, Jose E

    2012-08-15

    The new pathway nitrate-nitrite-nitric oxide (NO) has emerged as a physiological alternative to the classical enzymatic pathway for NO formation from l-arginine. Nitrate is converted to nitrite by commensal bacteria in the oral cavity and the nitrite formed is then swallowed and reduced to NO under the acidic conditions of the stomach. In this study, we tested the hypothesis that increases in gastric pH caused by omeprazole could decrease the hypotensive effect of oral sodium nitrite. We assessed the effects of omeprazole treatment on the acute hypotensive effects produced by sodium nitrite in normotensive and L-NAME-hypertensive free-moving rats. In addition, we assessed the changes in gastric pH and plasma levels of nitrite, NO(x) (nitrate+nitrite), and S-nitrosothiols caused by treatments. We found that the increases in gastric pH induced by omeprazole significantly reduced the hypotensive effects of sodium nitrite in both normotensive and L-NAME-hypertensive rats. This effect of omeprazole was associated with no significant differences in plasma nitrite, NO(x), or S-nitrosothiol levels. Our results suggest that part of the hypotensive effects of oral sodium nitrite may be due to its conversion to NO in the acidified environment of the stomach. The increase in gastric pH induced by treatment with omeprazole blunts part of the beneficial cardiovascular effects of dietary nitrate and nitrite. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Exogenous L-Arginine Attenuates the Effects of Angiotensin II on Renal Hemodynamics and the Pressure Natriuresis-Diuresis Relationship

    PubMed Central

    Das, Satarupa; Mattson, David L.

    2014-01-01

    SUMMARY Administration of exogenous L-Arginine (L-Arg) attenuates Angiotensin II (AngII)-mediated hypertension and kidney disease in rats. The present study assessed renal hemodynamics and pressure-diuresis-natriuresis in anesthetized rats infused with vehicle, AngII (20 ng/kg/min, iv) or AngII + L-Arg (300 µg/kg/min, iv). Increasing renal perfusion pressure (RPP) from approximately 100 to 140 mmHg resulted in a 9–10 fold increase in urine flow and sodium excretion rate in control animals. In comparison, AngII infusion significantly reduced renal blood flow (RBF) and glomerular filtration rate (GFR) by 40–42% and blunted the pressure-dependent increase in urine flow and sodium excretion rate by 54–58% at elevated RPP. Supplementation of L-Arg reversed the vasoconstrictor effects of AngII and restored pressure-dependent diuresis to levels not significantly different from control rats. Experiments in isolated aortic rings were performed to assess L-Arg effects on the vasculature. Dose-dependent contraction to AngII (10−10M to 10−7M) was observed with a maximal force equal to 27±3% of the response to 10−5M phenylephrine. Contraction to 10−7M AngII was blunted by 75±3% with 10−4M L-Arg. The influence of L-Arg to blunt AngII mediated contraction was eliminated by endothelial denudation or incubation with nitric oxide synthase inhibitors. Moreover, the addition of 10−3M cationic or neutral amino acids, which compete with L-Arg for cellular uptake, blocked the effect of L-Arg. Anionic amino acids did not influence the effects of L-Arg on AngII-mediated contraction. These studies indicate that L-Arg blunts AngII-mediated vascular contraction by an endothelial- and NOS-dependent mechanism involving cellular uptake of L-Arg. PMID:24472006

  9. MRI Reveals Edema in Larynx (But Not in Brain) During Anaphylactic Hypotension in Anesthetized Rats

    PubMed Central

    Toyota, Ichiro; Tanida, Mamoru; Wang, Mofei; Kurata, Yasutaka; Tonami, Hisao

    2013-01-01

    Purpose Anaphylactic shock is sometimes accompanied by local interstitial edema due to increased vascular permeability. We performed magnetic resonance imaging (MRI) to compare edema in the larynx and brain of anesthetized rats during anaphylactic hypotension versus vasodilator-induced hypotension. Methods Male Sprague Dawley rats were subjected to hypotension induced by the ovalbumin antigen (n=7) or a vasodilator sodium nitroprusside (SNP; n=7). Apparent diffusion coefficient (ADC) and T2-relaxation time (T2RT) were quantified on MRI performed repeatedly for up to 68 min after the injection of either agent. The presence of laryngeal edema was also examined by histological examination. Separately, the occurrence of brain edema was assessed by measuring brain water content using the wet/dry method in rats with anaphylaxis (n=5) or SNP (n=5) and the non-hypotensive control rats (n=5). Mast cells in hypothalamus were morphologically examined. Results Mean arterial blood pressure similarly decreased to 35 mmHg after an injection of the antigen or SNP. Hyperintensity on T2-weighted images (as reflected by elevated T2RT) was found in the larynx as early as 13 min after an injection of the antigen, but not SNP. A postmortem histological examination revealed epiglottic edema in the rats with anaphylaxis, but not SNP. In contrast, no significant changes in T2RT or ADC were detectable in the brains of any rats studied. In separate experiments, the quantified brain water content did not increase in either anaphylaxis or SNP rats, as compared with the non-hypotensive control rats. The numbers of mast cells with metachromatic granules in the hypothalamus were not different between rats with anaphylaxis and SNP, suggesting the absence of anaphylactic reaction in hypothalamus. Conclusion Edema was detected using the MRI technique in the larynx during rat anaphylaxis, but not in the brain. PMID:24179686

  10. MRI reveals edema in larynx (but not in brain) during anaphylactic hypotension in anesthetized rats.

    PubMed

    Toyota, Ichiro; Tanida, Mamoru; Shibamoto, Toshishige; Wang, Mofei; Kurata, Yasutaka; Tonami, Hisao

    2013-11-01

    Anaphylactic shock is sometimes accompanied by local interstitial edema due to increased vascular permeability. We performed magnetic resonance imaging (MRI) to compare edema in the larynx and brain of anesthetized rats during anaphylactic hypotension versus vasodilator-induced hypotension. Male Sprague Dawley rats were subjected to hypotension induced by the ovalbumin antigen (n=7) or a vasodilator sodium nitroprusside (SNP; n=7). Apparent diffusion coefficient (ADC) and T2-relaxation time (T2RT) were quantified on MRI performed repeatedly for up to 68 min after the injection of either agent. The presence of laryngeal edema was also examined by histological examination. Separately, the occurrence of brain edema was assessed by measuring brain water content using the wet/dry method in rats with anaphylaxis (n=5) or SNP (n=5) and the non-hypotensive control rats (n=5). Mast cells in hypothalamus were morphologically examined. Mean arterial blood pressure similarly decreased to 35 mmHg after an injection of the antigen or SNP. Hyperintensity on T2-weighted images (as reflected by elevated T2RT) was found in the larynx as early as 13 min after an injection of the antigen, but not SNP. A postmortem histological examination revealed epiglottic edema in the rats with anaphylaxis, but not SNP. In contrast, no significant changes in T2RT or ADC were detectable in the brains of any rats studied. In separate experiments, the quantified brain water content did not increase in either anaphylaxis or SNP rats, as compared with the non-hypotensive control rats. The numbers of mast cells with metachromatic granules in the hypothalamus were not different between rats with anaphylaxis and SNP, suggesting the absence of anaphylactic reaction in hypothalamus. Edema was detected using the MRI technique in the larynx during rat anaphylaxis, but not in the brain.

  11. Pharmacological observations on the hypotensive action of extracts of teleost fish urophyses (urotensin I) in the rat

    PubMed Central

    Lederis, K.; Medaković, M.

    1974-01-01

    1 Intravenous injections of urotensin I regularly caused a long-lasting, dose-related, lowering of blood pressure and an increase in heart rate in conscious rats, or a reduction in perfusion pressure in the isolated hind limb of the rat. 2 After subcutaneous administration, the hypotensive effect of urotensin I was greater in extent and in duration (> 24 hours). 3 Anaesthesia with ether, chloralose, pentobarbitone and thiobarbitone caused a decrease in blood pressure and only slightly diminished the hypotensive effect of urotensin. 4 Mecamylamine, hexamethonium, atropine, phenoxybenzamine, propranolol and diphenhydramine did not alter the effect of urotensin in conscious rats or in the isolated hind limb, although the effects of the respective agonists, i.e. nicotine, acetylcholine, noradrenaline, isoprenaline and histamine were inhibited. 5 In conscious rats, pressor effects of adrenaline, noradrenaline, nicotine and angiotensin II, and depressor effects of acetylcholine and bradykinin, were decreased or inhibited, whereas the hypotensive effect of phenoxybenzamine was potentiated by previous administration of urotensin I. Carotid occlusion reflex was partially inhibited by lower doses of urotensin and abolished by higher doses in rats lightly anaesthetized with chloralose. Urotensin elicited postural hypotension in rats anaesthetized with pentobarbitone. 6 The increase in heart rate produced by urotensin was not affected by phenoxybenzamine, but was abolished by propranolol or ganglion blocking agents (mecamylamine or hexamethonium). 7 It is concluded that urotensin elicits hypotension in the rat by a direct dilatory action on the resistance vessels causing a simultaneous reflex tachycardia. PMID:4375526

  12. [Comparison of metaraminol, phenylephrine and ephedrine in prophylaxis and treatment of hypotension in cesarean section under spinal anesthesia].

    PubMed

    Aragão, Fábio Farias de; Aragão, Pedro Wanderley de; Martins, Carlos Alberto de Souza; Salgado Filho, Natalino; Barroqueiro, Elizabeth de Souza Barcelos

    2014-01-01

    Maternal hypotension is a common complication after spinal anesthesia for cesarean section, with deleterious effects on the fetus and mother. Among the strategies aimed at minimizing the effects of hypotension, vasopressor administration is the most efficient. The aim of this study was to compare the efficacy of phenylephrine, metaraminol, and ephedrine in the prevention and treatment of hypotension after spinal anesthesia for cesarean section. Ninety pregnant women, not in labor, undergoing cesarean section were randomized into three groups to receive a bolus followed by continuous infusion of vasopressor as follows: phenylephrine group (50μg+50μg/min); metaraminol group (0.25mg+0.25mg/min); ephedrine group (4mg+4mg/min). Infusion dose was doubled when systolic blood pressure decreased to 80% of baseline and a bolus was given when systolic blood pressure decreased below 80%. The infusion dose was divided in half when systolic blood pressure increased to 120% and was stopped when it became higher. The incidence of hypotension, nausea and vomiting, reactive hypertension, bradycardia, tachycardia, Apgar scores, and arterial cord blood gases were assessed at the 1st and 5th minutes. There was no difference in the incidence of hypotension, bradycardia, reactive hypertension, infusion discontinuation, atropine administration or Apgar scores. Rescue boluses were higher only in the ephedrine group compared to metaraminol group. The incidence of nausea and vomiting and fetal acidosis were greater in the ephedrine group. The three drugs were effective in preventing hypotension; however, fetal effects were more frequent in the ephedrine group, although transient. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  13. Circulatory Insufficiency and Hypotension Related to the Ductus Arteriosus in Neonates

    PubMed Central

    Rios, Danielle R.; Bhattacharya, Soume; Levy, Philip T.; McNamara, Patrick J.

    2018-01-01

    The biological role of the ductus arteriosus (DA) in neonates varies from an innocent bystander role during normal postnatal transition, to a supportive role when there is compromise to either systemic or pulmonary blood flow, to a pathological state in the presence of hemodynamically significant systemic to pulmonary shunts, as occurs in low birth weight infants. Among a wide array of clinical manifestations arising due to the ductal entity, systemic circulatory insufficiency and hypotension are of significant concern as they are particularly challenging to manage. An understanding of the physiologic interplay between the DA and the circulatory system is the key to developing appropriate targeted therapeutic strategies. In this review, we discuss the relationship of systemic hypotension to the DA, emphasizing the importance of critical thinking and a precise individual approach to intensive care support. We particularly focus on the variable states of hypotension arising directly due to a hemodynamically significant DA or seen in the period following successful surgical ligation. In addition, we explore the mechanistic contributions of the ductus to circulatory insufficiency that may manifest during the transitional period, states of maladapted transition (such as acute pulmonary hypertension of the newborn), and congenital heart disease (both ductal dependent and non-ductal dependent lesions). Understanding the dynamic modulator role of the ductus according to the ambient physiology enables a more precise approach to management. We review the pathophysiology, clinical manifestations, diagnosis, monitoring, and therapeutic intervention for the spectrum of DA-related circulatory compromise. PMID:29600242

  14. CADASIL accelerated by acute hypotension: Arterial and venous contribution to leukoaraiosis.

    PubMed

    Pettersen, Jacqueline A; Keith, Julia; Gao, Fuqiang; Spence, J David; Black, Sandra E

    2017-03-14

    To underline the importance of blood pressure regulation in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and to describe changes that occur in the veins in this condition, specifically venous collagenosis associated with leukoaraiosis. Case report with neuroimaging and pathologic data. A 61-year-old man with genetically confirmed CADASIL was initially lucid following a motor vehicle accident but subsequently became hypotensive (60/40 mm Hg) due to an open femur fracture and required intubation. Multiple new white matter infarcts appeared on brain imaging. A second hypotensive episode days later was associated with new coin-sized infarcts in the bilateral corona radiata and cerebellar peduncles, and resulted in quadriplegia. No embolic source was found on cardiac or vascular imaging. He died 5 weeks post trauma. Autopsy revealed extensive subcortical and periventricular leukoencephalopathy and multiple cavitations involving deep subcortical gray and white matter. Small arteries had thickened walls, disruption of the muscularis, and intimal periodic acid-Schiff (PAS)-positive material. Both larger periventricular and small caliber veins had thickened walls that were PAS-negative and trichrome-positive, consistent with venous collagenosis. There was no pathologic evidence of global hypoxia or diffuse axonal injury. The findings suggest rapid acceleration of CADASIL pathology from acute hypotension in the setting of impaired vasoreactivity. In addition, collagenosis of veins in the affected white matter regions suggests that the veins may play an important, though largely overlooked, role in maintaining white matter integrity. © 2017 American Academy of Neurology.

  15. Dilator and constrictor response of renal vasculature during acute renal hypotension in anesthetized goats. Role of nitric oxide.

    PubMed

    Diéguez, Godofredo; García-Villalón, Angel Luis

    2011-01-01

    The relative role of NO derived from endothelium NO synthase (eNOS) and neuronal NO synthase (nNOS) in renovascular reactivity during renal hypotension is unknown. To examine this issue, we recorded the effects of unspecific inhibitor of NO synthase N(w)-nitro-L-arginine methyl esther (L-NAME) and inhibitor of nNOS 7-nitroindazole monosodium salt (7-NINA) on renal vasodilator and vasoconstrictor responses in anesthetized goats during renal hypotension by constricting the abdominal aorta. Intrarenal administration of L-NAME and hypotension, either untreated or treated with L-NAME, decreased resting renal blood flow, and the increases in renal blood flow by acetylcholine but not those by sodium nitroprusside were tempered, and the decreases by norepinephrine and angiotensin II were augmented. Intraperitoneal administration of 7-NINA did not affect, and 7-NINA+hypotension decreased renal blood flow, and under these conditions the increases in renal blood flow by acetylcholine and sodium nitroprusside were not modified, and the decreases by norepinephrine and angiotensin II were slightly (during 7-NINA) or consistently augmented (7-NINA+hypotension). Therefore, NO derived from eNOS plays a significant role, while that derived from nNOS plays a little role, if any, to regulate renal blood flow and to mediate acetylcholine-induced vasodilation, as well to modulate renal vasoconstriction by norepinephrine and angiotensin II. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Effect of perturbations and a meal on superior mesenteric artery flow in patients with orthostatic hypotension

    NASA Technical Reports Server (NTRS)

    Fujimura, J.; Camilleri, M.; Low, P. A.; Novak, V.; Novak, P.; Opfer-Gehrking, T. L.

    1997-01-01

    Our aims were to evaluate to role of superior mesenteric blood flow in the pathophysiology of orthostatic hypotension in patients with generalized autonomic failure. METHODS: Twelve patients with symptomatic neurogenic orthostatic hypotension and 12 healthy controls underwent superior mesenteric artery flow measurements using Doppler ultrasonography during head-up tilt and tilt plus meal ingestion. Autonomic failure was assessed using standard tests of the function of the sympathetic adrenergic, cardiovagal and postganglionic sympathetic sudomotor function. RESULTS: Superior mesenteric flow volume and time-averaged velocity were similar in patients and controls at supine rest; however, responses to cold pressor test and upright tilt were attenuated (p < 0.05) in patients compared to controls. Head-up tilt after the meal evoked a profound fall of blood pressure and mesenteric blood flow in the patients; the reduction of mesenteric blood flow correlated (r = 0.89) with the fall of blood pressure in these patients, providing another manifestation of failed baroreflexes. We make the novel finding that the severity of postprandial orthostatic hypotension regressed negatively with the postprandial increase in mesenteric flow in patients with orthostatic hypotension. CONCLUSION: Mesenteric flow is under baroreflex control, which when defective, results in, or worsens orthostatic hypotension. Its large size and baroreflexivity renders it quantitatively important in the maintenance of postural normotension. The effects of orthostatic stress can be significantly attenuated by reducing the splanchnic-mesenteric volume increase in response to food. Evaluation of mesenteric flow in response to eating and head-up tilt provide important information on intra-abdominal sympathetic adrenergic function, and the ability of the patient to cope with orthostatic stress.

  17. Characterization of renal response to prolonged immersion in normal man

    NASA Technical Reports Server (NTRS)

    Epstein, M.; Denunzio, A. G.; Ramachandran, M.

    1980-01-01

    ?jDuring the initial phase of space flight, there is a translocation of fluid from the lower parts of the body to the central vascular compartment with a resultant natriuresis, diuresis, and weight loss. Because water immersion is regarded as an appropriate model for studying the redistribution of fluid that occurs in weightlessness, an immersion study of relatively prolonged duration was carried out in order to characterize the temporal profile of the renal adaptation to central hypervolemia. Twelve normal male subjects underwent an immersion study of 8-h duration in the sodium-replete state. Immersion resulted in marked natriuresis and diuresis which were sustained throughout the immersion period. The failure of that natriuresis and diuresis of immersion to abate or cease despite marked extracellular fluid volume contraction as evidenced by a mean weight loss of -2.2 + or - 0.3 kg suggests that central blood volume was not restored to normal and that some degree of central hypervolemia probably persisted.

  18. Effect of midodrine on chlorpromazine-induced orthostatic hypotension in rabbits: comparison with amezinium, etilefrine and droxidopa.

    PubMed

    Kurihara, J; Takata, Y; Suzuki, S; Okubo, Y; Kato, H

    2000-12-01

    Orthostatic hypotension was produced in urethane-anesthetized rabbit by a combination of chlorpromazine (0.1 mg/kg, i.v.) and 45 degrees head-up tilt. The effect of midodrine (1 and 3 mg/kg, i.d.) was investigated in comparison with amezinium (10 and 30 mg/kg, i.d.), etilefrine (10 and 30 mg/kg, i.d.) and droxidopa (30 and 100 mg/kg, i.d.). The higher doses of each drug significantly mitigated the chlorpromazine-induced orthostatic hypotension, while none of the lower doses caused a significant effect. The effect of midodrine developed most rapidly; a significant effect was observed 25 min after administration. The order of onset time was midodrine < etilefrine < amezinium < droxidopa. The effect of droxidopa was significant only at 130 to 160 min after administration. The amplitude of effect was in the following order; midodrine = droxidopa > or = etilefrine > amezinium. Midodrine (3 mg/kg, i.d.) mitigated orthostatic hypotension induced by prazosin (0.1 mg/kg, i.v.), but not by pentolinium (0.6 mg/kg, i.v.). It is suggested that midodrine competes with chlorpromazine at alpha1-adrenoceptors and subsequently recovers reflex vasoconstriction. Midodrine may be useful to protect patients with impaired baroreflex activity from accidental orthostatic hypotension during treatment with neuroleptics.

  19. Efficacy of atomoxetine versus midodrine for the treatment of orthostatic hypotension in autonomic failure.

    PubMed

    Ramirez, Claudia E; Okamoto, Luis E; Arnold, Amy C; Gamboa, Alfredo; Diedrich, André; Choi, Leena; Raj, Satish R; Robertson, David; Biaggioni, Italo; Shibao, Cyndya A

    2014-12-01

    The clinical presentation of autonomic failure is orthostatic hypotension. Severely affected patients require pharmacological treatment to prevent presyncopal symptoms or frank syncope. We previously reported in a proof of concept study that pediatric doses of the norepinephrine transporter blockade, atomoxetine, increases blood pressure in autonomic failure patients with residual sympathetic activity compared with placebo. Given that the sympathetic nervous system is maximally activated in the upright position, we hypothesized that atomoxetine would be superior to midodrine, a direct vasoconstrictor, in improving upright blood pressure and orthostatic hypotension-related symptoms. To test this hypothesis, we compared the effect of acute atomoxetine versus midodrine on upright systolic blood pressure and orthostatic symptom scores in 65 patients with severe autonomic failure. There were no differences in seated systolic blood pressure (means difference=0.3 mm Hg; 95% confidence [CI], -7.3 to 7.9; P=0.94). In contrast, atomoxetine produced a greater pressor response in upright systolic blood pressure (means difference=7.5 mm Hg; 95% CI, 0.6 to 15; P=0.03) compared with midodrine. Furthermore, atomoxetine (means difference=0.4; 95% CI, 0.1 to 0.8; P=0.02), but not midodrine (means difference=0.5; 95% CI, -0.1 to 1.0; P=0.08), improved orthostatic hypotension-related symptoms as compared with placebo. The results of our study suggest that atomoxetine could be a superior therapeutic option than midodrine for the treatment of orthostatic hypotension in autonomic failure. © 2014 American Heart Association, Inc.

  20. A systematic review of vasopressor blood pressure targets in critically ill adults with hypotension.

    PubMed

    Hylands, Mathieu; Moller, Morten Hylander; Asfar, Pierre; Toma, Augustin; Frenette, Anne Julie; Beaudoin, Nicolas; Belley-Côté, Émilie; D'Aragon, Frédérick; Laake, Jon Henrik; Siemieniuk, Reed Alexander; Charbonney, Emmanuel; Lauzier, François; Kwong, Joey; Rochwerg, Bram; Vandvik, Per Olav; Guyatt, Gordon; Lamontagne, François

    2017-07-01

    Clinicians must balance the risks from hypotension with the potential adverse effects of vasopressors. Experts have recommended a mean arterial pressure (MAP) target of at least 65 mmHg, and higher in older patients and in patients with chronic hypertension or atherosclerosis. We conducted a systematic review of randomized-controlled trials comparing higher vs lower blood pressure targets for vasopressor therapy administered to hypotensive critically ill patients. We searched MEDLINE®, EMBASE™, and the Cochrane Central Register of Controlled Trials for studies of higher vs lower blood pressure targets for vasopressor therapy in critically ill hypotensive adult patients. Two reviewers independently assessed trial eligibility based on titles and abstracts, and they then selected full-text reports. Outcomes, subgroups, and analyses were prespecified. We used GRADE (Grading of Recommendations Assessment, Development and Evaluation) to rate the overall confidence in the estimates of intervention effects. Of 8001 citations, we retrieved 57 full-text articles and ultimately included two randomized-controlled trials (894 patients). Higher blood pressure targets were not associated with lower mortality (relative risk [RR], 1.05; 95% confidence interval [CI], 0.90 to 1.23; P = 0.54), and neither age (P = 0.17) nor chronic hypertension (P = 0.32) modified the overall effect. Nevertheless, higher blood pressure targets were associated with a greater risk of new-onset supraventricular cardiac arrhythmia (RR, 2.08; 95% CI, 1.28 to 3.38; P < 0.01). Current evidence does not support a MAP target > 70 mmHg in hypotensive critically ill adult patients requiring vasopressor therapy.

  1. Influence of endogenous opiates on the hypotensive action of taurine in DOCA-salt rats.

    PubMed

    Sato, Y; Fujita, T

    1988-12-01

    We studied the role of endogenous opiate activation in the hypotensive action of taurine, a sulphur amino acid, in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Previous work had shown that supplementation with 1% taurine reduced blood pressure when given after DOCA-salt hypertension had been established. In the present study, in conscious rats, intraperitoneal injection of naloxone, an opiate antagonist, increased blood pressure in taurine-supplemented DOCA-salt rats, but not in DOCA-salt rats or vehicle-treated control rats. These results suggest that activation of an endogenous opiate might contribute to the hypotensive action of taurine in DOCA-salt hypertensive rats.

  2. Droxidopa for neurogenic orthostatic hypotension

    PubMed Central

    Freeman, Roy; Biaggioni, Italo; Low, Phillip; Pedder, Simon; Hewitt, L. Arthur; Mauney, Joe; Feirtag, Michael; Mathias, Christopher J.

    2014-01-01

    Objective: To determine whether droxidopa, an oral norepinephrine precursor, improves symptomatic neurogenic orthostatic hypotension (nOH). Methods: Patients with symptomatic nOH due to Parkinson disease, multiple system atrophy, pure autonomic failure, or nondiabetic autonomic neuropathy underwent open-label droxidopa dose optimization (100–600 mg 3 times daily), followed, in responders, by 7-day washout and then a 7-day double-blind trial of droxidopa vs placebo. Outcome measures included patient self-ratings on the Orthostatic Hypotension Questionnaire (OHQ), a validated, nOH-specific tool that assesses symptom severity and symptom impact on daily activities. Results: From randomization to endpoint (n = 162), improvement in mean OHQ composite score favored droxidopa over placebo by 0.90 units (p = 0.003). Improvement in OHQ symptom subscore favored droxidopa by 0.73 units (p = 0.010), with maximum change in “dizziness/lightheadedness.” Improvement in symptom-impact subscore favored droxidopa by 1.06 units (p = 0.003), with maximum change for “standing a long time.” Mean standing systolic blood pressure (BP) increased by 11.2 vs 3.9 mm Hg (p < 0.001), and mean supine systolic BP by 7.6 vs 0.8 mm Hg (p < 0.001). At endpoint, supine systolic BP >180 mm Hg was observed in 4.9% of droxidopa and 2.5% of placebo recipients. Adverse events reported in ≥3% of double-blind droxidopa recipients were headache (7.4%) and dizziness (3.7%). No patients discontinued double-blind treatment because of adverse events. Conclusions: In patients with symptomatic nOH, droxidopa improved symptoms and symptom impact on daily activities, with an associated increase in standing systolic BP, and was generally well tolerated. Classification of evidence: This study provides Class I evidence that in patients with symptomatic nOH who respond to open-label droxidopa, droxidopa improves subjective and objective manifestation of nOH at 7 days. PMID:24944260

  3. The SLUScore: A Novel Method for Detecting Hazardous Hypotension in Adult Patients Undergoing Noncardiac Surgical Procedures

    PubMed Central

    Yuan, Hui; Dryden, Jefferson K.; Strehl, Kristen E.; Cywinski, Jacek B.; Ehrenfeld, Jesse M.; Bromley, Pamela

    2017-01-01

    BACKGROUND: It has been suggested that longer-term postsurgical outcome may be adversely affected by less than severe hypotension under anesthesia. However, evidence-based guidelines are unavailable. The present study was designed to develop a method for identifying patients at increased risk of death within 30 days in association with the severity and duration of intraoperative hypotension. METHODS: Intraoperative mean arterial blood pressure recordings of 152,445 adult patients undergoing noncardiac surgery were analyzed for periods of time accumulated below each one of the 31 thresholds between 75 and 45 mm Hg (hypotensive exposure times). In a development cohort of 35,904 patients, the associations were sought between each of these 31 cumulative hypotensive exposure times and 30-day postsurgical mortality. On the basis of covariable-adjusted percentage increases in the odds of mortality per minute elapsed of hypotensive exposure time, certain sets of exposure time limits were calculated that portended certain percentage increases in the odds of mortality. A novel risk-scoring method was conceived by counting the number of exposure time limits that had been exceeded within each respective set, one of them being called the SLUScore. The validity of this new method in identifying patients at increased risk was tested in a multicenter validation cohort consisting of 116,541 patients from Cleveland Clinic, Vanderbilt and Saint Louis Universities. Data were expressed as 95% confidence interval, P < .05 considered significant. RESULTS: Progressively greater hypotensive exposures were associated with greater 30-day mortality. In the development cohort, covariable-adjusted (age, Charlson score, case duration, history of hypertension) exposure limits were identified for time accumulated below each of the thresholds that portended certain identical (5%–50%) percentage expected increases in the odds of mortality. These exposure time limit sets were shorter in patients

  4. Depression of fractional sodium reabsorption by the proximal tubule of the dog without sodium diuresis

    PubMed Central

    Howards, Stuart S.; Davis, Bernard B.; Knox, Franklyn G.; Wright, Fred S.; Berliner, Robert W.

    1968-01-01

    The effect of infusions of hyperoncotic solutions on fractional sodium reabsorption by the proximal tubule of the dog was studied by the recollection micropuncture method. Tubule fluid to plasma inulin concentration ratios were measured for identified proximal tubule segments before and after infusion of 25% albumin or dextran solutions. Results were compared with changes in fractional reabsorption during saline diuresis. Plasma volume increased 66% ± SE 5.8 after infusion of albumin solution and 94% ± SE 8.2 after infusion of dextran solution. Fractional sodium reabosorption by the proximal tubule was depressed after infusion of both of these hyperoncotic solutions. Nevertheless, changes in sodium excretion after infusion of albumin and dextran were small. In contrast, after infusions of isotonic sodium chloride solution, which increased plasma volume 61% ± SE 5.8, a decrease in fractional reabsorption of 50.7% ± SE 7.2 was associated with large changes in sodium excretion. PMID:5658588

  5. A polymorphism in the glucocorticoid receptor gene is associated with refractory hypotension in premature infants.

    PubMed

    Ogasawara, Kei; Sato, Maki; Hashimoto, Koichi; Imamura, Takashi; Go, Hayato; Hosoya, Mitsuaki

    2018-06-01

    Glucocorticoids play an important role in endocrine control. The association of glucocorticoid receptor (GR) gene polymorphisms with altered sensitivity to glucocorticoid therapy has been reported in adults. However, there are few such reports in infants. The present study analyzed the prevalence of four GR polymorphisms in preterm infants born before 30 weeks of gestation and determined the associations between these polymorphisms and clinical outcomes in the infants. Totally, 41 preterm infants born at two hospitals in Fukushima were retrospectively screened for the presence of four GR gene polymorphisms, using a TaqMan single-nucleotide polymorphism genotyping assay. The effect of GR gene polymorphisms on clinical outcomes during hospitalization was evaluated. The following primary clinical outcomes were assessed: refractory hypotension in the acute phase and/or severe bronchopulmonary dysplasia, maximum dopamine and dobutamine doses administered, and total hydrocortisone dose administered in the first 48 h of life. Multivariate analysis with logistic regression was used to assess the association between clinical factors and refractory hypotension. Of the four GR polymorphisms, only the BclI polymorphism was detected. The genotype distribution was as follows: C/C, 33; C/G, 8; and G/G, 0 infants. Significant differences were observed between the C/C and C/G genotypes with respect to the following variables: refractory hypotension (6% vs. 50%), dopamine dose [3.0 (2.0-4.0) vs. 4.8 (4.0-7.5) μg/kg/min], dobutamine dose [2.4 (0.0-3.6) vs. 4.0 (0-10.0) μg/kg/min], and total hydrocortisone dose administered in the first 48 h of life [2.0 (0-10.0) vs. 6.0 (0-12.0) mg/kg]. Multivariate analysis showed that the BclI genotype (C/C) was significantly less associated with refractory hypotension in the acute phase (odds ratio, 0.008; 95% confidence interval, 0.000-0.371; p = 0.013). The incidence of refractory hypotension in infants with the C/C genotype was initially

  6. Bed Rest and Orthostatic-Hypotensive Intolerance

    NASA Technical Reports Server (NTRS)

    Schneider, Suzanne M.

    2000-01-01

    Orthostatic tolerance may be defined as the ability of humans to maintain cerebral perfusion and consciousness upon movement from a supine or sitting position to the upright posture; for example, subjects can stand suddenly or be tilted to the head-up body position. Similar but not identical physiological responses can be induced by positive G(sub Z) (head to foot) acceleration or exposure to lower body negative pressure (LBNP). The objective is to suddenly shift blood to the lower body to determine how effectively cardiovascular and neural-hormonal compensatory responses react to maintain blood pressure. In the most precise method for measuring tolerance, individuals would be stressed until they faint (syncope). However, the potential consequences and discomforts of such a test usually prohibit such a procedure so that few investigators actually induce syncope. In a more common approach, subjects are exposed to a given level of stress, for example, head-up tilt for 15 min, and any increases in heart rate or decreases in blood pressure are interpreted as indicators of progress toward syncope. Presumably, the greater the perturbation of heart rate and blood pressure, the closer to "tolerance," i.e., point of unconsciousness. Another more appropriate approach is to induce a progressively increasing hypotensive stress until pre-determined physiological responses or pre-syncopal symptoms appear. The physiological criteria may include a sudden drop in systolic blood pressure (greater than 25 mm/min), a sudden drop in heart rate (greater than 15 beats/min), or a systolic blood pressure less than 70 mmHg. The most common pre-syncopal symptoms include lightheadedness, stomach awareness or distress, feelings of warmth, tingly skin, and light to profuse sweating. Usually a combination of physiological responses and symptoms occurs such that, on different days, the tolerance time to the same orthostatic protocol is reproducible for a given individual. The assumption is that

  7. Droxidopa in neurogenic orthostatic hypotension

    PubMed Central

    Kaufmann, Horacio; Norcliffe-Kaufmann, Lucy; Palma, Jose-Alberto

    2015-01-01

    Neurogenic orthostatic hypotension (nOH) is a fall in blood pressure on standing due to reduced norepinephrine release from sympathetic nerve terminals. nOH is a feature of several neurological disorders that affect the autonomic nervous system, most notably Parkinson disease (PD), multiple system atrophy, pure autonomic failure and other autonomic neuropathies. Droxidopa, an orally active synthetic amino acid that is converted to norepinephrine by the enzyme aromatic L-amino acid decarboxylase (dopa-decarboxylase), was recently approved by the FDA for the short-term treatment of nOH. It is presumed to raise blood pressure by acting at the neurovascular junction to increase vascular tone. This review summarizes the pharmacological properties of droxidopa, its mechanism of action, and the efficacy and safety results of clinical trials. PMID:26092297

  8. Droxidopa in neurogenic orthostatic hypotension.

    PubMed

    Kaufmann, Horacio; Norcliffe-Kaufmann, Lucy; Palma, Jose-Alberto

    2015-01-01

    Neurogenic orthostatic hypotension (nOH) is a fall in blood pressure (BP) on standing due to reduced norepinephrine release from sympathetic nerve terminals. nOH is a feature of several neurological disorders that affect the autonomic nervous system, most notably Parkinson disease (PD), multiple system atrophy (MSA), pure autonomic failure (PAF), and other autonomic neuropathies. Droxidopa, an orally active synthetic amino acid that is converted to norepinephrine by the enzyme aromatic L-amino acid decarboxylase (dopa-decarboxylase), was recently approved by the FDA for the short-term treatment of nOH. It is presumed to raise BP by acting at the neurovascular junction to increase vascular tone. This article summarizes the pharmacological properties of droxidopa, its mechanism of action, and the efficacy and safety results of clinical trials.

  9. Biphasic changes in fetal heart rate variability in preterm fetal sheep developing hypotension after acute on chronic lipopolysaccharide exposure.

    PubMed

    Lear, Christopher A; Davidson, Joanne O; Booth, Lindsea C; Wassink, Guido; Galinsky, Robert; Drury, Paul P; Fraser, Mhoyra; Bennet, Laura; Gunn, Alistair J

    2014-08-15

    Perinatal exposure to infection is highly associated with adverse outcomes. Experimentally, acute, severe exposure to gram-negative bacterial lipopolysaccharide (LPS) is associated with increased fetal heart rate variability (FHRV). It is unknown whether FHRV is affected by subclinical infection with or without acute exacerbations. We therefore tested the hypothesis that FHRV would be associated with hypotension after acute on chronic exposure to LPS. Chronically instrumented fetal sheep at 0.7 gestation were exposed to a continuous low-dose LPS infusion (n = 12, 100 ng/kg over 24 h, followed by 250 ng·kg(-1)·24 h(-1) for a further 96 h) or the same volume of saline (n = 10). Boluses of either 1 μg LPS or saline were given at 48, 72, and 96 h. Low-dose infusion was not associated with hemodynamic or FHRV changes. The first LPS bolus was associated with tachycardia and suppression of nuchal electromyographic activity in all fetuses. Seven of twelve fetuses developed hypotension (a fall in mean arterial blood pressure ≥5 mmHg). FHRV was transiently increased only at the onset of hypotension, in association with increased cytokine induction and electroencephalogram suppression. FHRV then fell before the nadir of hypotension, with transient suppression of short-term FHRV. After the second LPS bolus, the hypotension group showed a biphasic pattern of a transient increase in FHRV followed by more prolonged suppression. These findings suggest that infection-related hypotension in the preterm fetus mediates the transient increase in FHRV and that repeated exposure to LPS leads to progressive loss of FHRV. Copyright © 2014 the American Physiological Society.

  10. Caffeine and diuresis during rest and exercise: A meta-analysis

    PubMed Central

    Coca, Aitor; Casa, Douglas J.; Antonio, Jose; Green, James M.; Bishop, Phillip A.

    2016-01-01

    Objectives Although ergogenic, acute caffeine ingestion may increase urine volume, prompting concerns about fluid balance during exercise and sport events. This meta-analysis evaluated caffeine induced diuresis in adults during rest and exercise. Design Meta-analysis. Methods A search of three databases was completed on November 1, 2013. Only studies that involved healthy adults and provided sufficient information concerning the effect size (ES) of caffeine ingestion on urine volume were included. Sixteen studies met the inclusion criteria, providing a total of 28 ESs for the meta-analysis. Heterogeneity was assessed using a random-effects model. Results The median caffeine dosage was 300 mg. The overall ES of 0.29 (95% confidence interval (CI) = 0.11-0.48, p = 0.001) corresponds to an increase in urine volume of 109 ± 195 mL or 16.0 ± 19.2% for caffeine ingestion vs. non-caffeine conditions. Subgroup meta-analysis confirmed exercise as a strong moderator: active ES = 0.10, 95% CI = −0.07 to 0.27, p = 0.248 vs. resting ES = 0.54, 95% CI = 0.22–0.85, p = 0.001 (Cochran's Q, p = 0.019). Females (ES = 0.75,95% CI = 0.38–1.13, p< 0.001) were more susceptible to diuretic effects than males (ES = 0.13,95% CI = −0.05 to 0.31, p = 0.158) (Cochran's Q, p = 0.003). Conclusions Caffeine exerted a minor diuretic effect which was negated by exercise. Concerns regarding unwanted fluid loss associated with caffeine consumption are unwarranted particularly when ingestion precedes exercise. PMID:25154702

  11. Hemodynamic response to fluid removal during hemodialysis: categorization of causes of intradialytic hypotension.

    PubMed

    Levin, Nathan W; de Abreu, Marcia H F G; Borges, Lucas E; Tavares Filho, Helcio A; Sarwar, Rabia; Gupta, Surendra; Hafeez, Tahir; Lev, Shaul; Williams, Caroline

    2018-04-14

    Intradialytic hypotension is a clinically significant problem, however, the hemodynamics that underlie ultrafiltration and consequent hypotensive episodes has not been studied comprehensively. Intradialytic cardiac output, cardiac power and peripheral resistance changes from pretreatment measurements were evaluated using a novel regional impedance cardiographic device (NICaS, NI Medical, Peta Tikva, Israel) in 263 hemodialysis sessions in 54 patients in dialysis units in the USA and Brazil with the goal of determining the various hemodynamic trends as blood pressure decreases. Hypotensive episodes occurred in 99 (13.5%) of 736 intra- and postdialytic evaluations. The hemodynamic profiles of the episodes were categorized: (i) The cardiac power index significantly decreased in 35% of episodes by 36%, from 0.66 [95% confidence interval (CI) 0.60-0.72] to 0.43 (95% CI 0.37-0.48) [w/m2] with a small reduction in the total peripheral resistance index. (ii) The total peripheral resistance index significantly decreased in 37.4% of episodes by 33%, from 3342 (95% CI 2824-3859) to 2251 (95% CI 1900-2602) [dyn × s/cm5 × m2] with a small reduction in the cardiac power index. (iii) Both the cardiac power index and total peripheral resistance index significantly decreased in 27.3% of episodes, the cardiac power index by 25% from 0.63 (95% CI 0.57-0.70) to 0.48 (95% CI 0.42-0.53) [w/m2] and the total peripheral resistance index by 23% from 2964 (95% CI 2428-3501) to 2266 (95% CI 1891-2642). The hemodynamic profiles clearly define specific hemodynamic mechanisms of cardiac power reduction and/or vasodilatation as underlying intradialytic hypotensive episodes. A reduction in cardiac power (reduction of both blood pressure and cardiac output) could be the result of preload reduction due to a high ultrafiltration rate with not enough refilling or low target weight. A reduction in peripheral resistance (reduction in blood pressure and increase in cardiac output) could be the result

  12. Refractory hypotension due to Rogaine® (minoxidil) ingestion managed with midodrine.

    PubMed

    Garrard, Alexander; Wood, Adam; Sollee, Dawn; Aaronson, Patrick

    2011-12-01

    Minoxidil (Rogaine®) is a direct vasodilator that can cause significant toxicity when ingested. We report a case of ingestion of topical minoxidil [Rogaine® (Johnson & Johnson Healthcare Products, Division of McNeil-PPC, Inc)] resulting in refractory hypotension that was successfully managed with the oral α (1) agonist midodrine. A 48-year-old male who ingested an eight ounce bottle of Rogaine® presented to the emergency department. The patient presented with a blood pressure of 57/45 mmHg and a pulse of 84 beats per minute. The patient received IV fluids and multiple vasopressors to maintain an adequate mean arterial pressure. Midodrine, an oral α (1) vasopressor, was added 10 hours post ingestion and was able to maintain an adequate mean arterial pressure. Over the next two days, midodrine was titrated down as his blood pressure returned to baseline. Midodrine may serve as an additional option to treat toxicant induced hypotension.

  13. Accuracy and Precision of Noninvasive Blood Pressure in Normo-, Hyper-, and Hypotensive Standing and Anesthetized Adult Horses.

    PubMed

    Heliczer, N; Lorello, O; Casoni, D; Navas de Solis, C

    2016-05-01

    Blood pressure is relevant to the diagnosis and management of many medical, cardiovascular and critical diseases. The accuracy of many commonly used noninvasive blood pressure (NIBP) monitors and the accuracy of NIBP measurements in hypo- and hypertensive standing horses has not been determined. The objective of this study was to investigate the accuracy of an oscillometric BP monitor in standing horses before and during pharmacologically induced hyper- and hypotension and to compare results in standing and anesthetized horses. Eight standing mares from a research herd (SG) and eight anesthetized horses from a hospital population (AG). Prospective experimental and observational studies. Invasive blood pressure (IBP) and NIBP, corrected to heart level, were measured simultaneously. In the SG hyper- and hypotension were induced by administration of phenylephrine (3 μg/kg/min IV for 15 minutes) and acepromazine (0.05 mg/kg IV), respectively. In the AG NIBP and IBP were recorded during regular hospital procedures. There was a significant correlation between mean NIBP and IBP in standing (R = 0.88, P < .001) and anesthetized horses (R = 0.81, P < .001). The mean bias (lower, upper limit of agreement) was 16.4(-16.1, 48.9) mmHg for mean BP in the SG and 0.5(-22.3, 23.2) mmHg in the AG. The NIBP device was capable of identifying the increase and decrease in BP in all horses, but in the SG significant correlation between NIBP and IBP was only detected for the normotensive phase. While the evaluated oscillometric BP device allowed estimation of BP and adequately differentiated marked trends, the accuracy and precision were low in standing horses. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  14. Harmane produces hypotension following microinjection into the RVLM: possible role of I(1)-imidazoline receptors.

    PubMed

    Musgrave, I F; Badoer, E

    2000-03-01

    The beta-carboline, harmane (0.1 - 1.0 nmol) produces dose dependent hypotension when microinjected unilaterally into the rostral ventrolateral medulla (RVLM) of the anaesthetized rat. The potency of harmane on blood pressure is similar to that of the imidazoline, clonidine. The hypotensive effects of both clonidine and harmane are reversed by microinjection of the relatively I(1)-receptor selective antagonist efaroxan (20 nmol). These results are consistent with harmane acting at an I(1)-receptor in the RVLM. This is the first report of an endogenous ligand for I(1)-receptors that has central effects on blood pressure.

  15. Aortic stiffness and hypotension episodes are associated with impaired cognitive function in older subjects with subjective complaints of memory loss.

    PubMed

    Scuteri, Angelo; Tesauro, Manfredi; Guglini, Letizia; Lauro, Davide; Fini, Massimo; Di Daniele, Nicola

    2013-11-20

    Though CV risk factors and markers of arterial aging are recognized risky for cognition, no study has simultaneously investigated the impact of multiple cardiac, arterial (large and small vessels), and hemodynamic parameters on cognitive function in older subjects. Two hundred eighty older subjects with subjective complaints of memory loss and no previous stroke (mean age 78.3 ± 6.3 years) were studied. Global cognitive function was evaluated with the Mini-Mental State Examination (MMSE). Cognitive impairment was defined as a MMSE < 21. We measured: traditional CV risk factors; aorta stiffness (Pulse Wave Velocity, PWV); LV mass; presence of WML at neuroimaging; episodes of hypotension (SBP <100 mmHg during 24 h Ambulatory Blood Pressure Monitoring). In both cross-sectional and longitudinal analyses PWV, WML, and episodes of hypotension were significantly associated with poorer cognitive function-controlling for age, sex, education, depression, traditional CV risk factors, and medications. LV mass was no longer associated with cognition in multiple regression. Older subjects with stiffer arteries or episodes of hypotension presented a 4-fold and an 11-fold, respectively, greater odds for progression from normal cognitive function to cognitive impairment. A synergistic effect between PWV, WML, and hypotension was observed: the occurrence of any two of PWV, WML, or hypotension was accompanied by lower MMSE; in the presence of all three factors, a further significant decline in cognitive function was observed. Systemic hemodynamic parameters (higher PWV and hypotension) together with cerebral microvascular damage (WML) are significantly associated with poorer cognitive function and may identify older subjects with subjective complaints of memory loss at higher risk of cognitive decline. © 2013.

  16. Long-Lasting Orthostatic Hypotension and Constipation After Celiac Plexus Block; A Case Report.

    PubMed

    Yousefshahi, Fardin; Tahmasebi, Mamak

    2018-02-01

    This case report presents a 55 years old man, presented with abdominal pain and diagnosed with a metastatic pancreatic tumor, who developed long lasting orthostatic hypotension and constipation following a celiac plexus block.

  17. Controlled hypotension versus normotensive resuscitation strategy for people with ruptured abdominal aortic aneurysm.

    PubMed

    Moreno, Daniel H; Cacione, Daniel G; Baptista-Silva, Jose C C

    2016-05-13

    An abdominal aortic aneurysm (AAA) is the pathological enlargement of the aorta and can develop in both men and women. Progressive aneurysm enlargement can lead to rupture. The rupture of an AAA is frequently fatal and accounts for the death from haemorrhagic shock of at least 45 people per 100,000 population. The outcome of people with ruptured AAA varies among countries and healthcare systems, with mortality ranging from 53% to 90%. Definitive treatment for ruptured AAA includes open surgery or endovascular repair. The management of haemorrhagic shock is crucial for the person's outcome and aims to restore organ perfusion and systolic blood pressure above 100 mm Hg through immediate and aggressive fluid replacement. This rapid fluid replacement is known as the normotensive resuscitation strategy. However, evidence suggests that infusing large volumes of cold fluid causes dilutional and hypothermic coagulopathy. The association of these factors may exacerbate bleeding, resulting in a 'lethal triad' of hypothermia, acidaemia, and coagulopathy. An alternative to the normotensive resuscitation strategy is the controlled (permissive) hypotension resuscitation strategy, with a target systolic blood pressure of 50 to 100 mm Hg. The principle of controlled or hypotensive resuscitation has been used in some management protocols for endovascular repair of ruptured AAA. It may be beneficial in preventing blood loss by avoiding the clot disruption caused by the rapid increase in systolic blood pressure; avoiding dilution of clotting factors, platelets and fibrinogen; and by avoiding the temperature decrease that inhibits enzyme activity involved in platelet and clotting factor function. To compare the effects of controlled (permissive) hypotension resuscitation and normotensive resuscitation strategies for people with ruptured AAA. The Cochrane Vascular Information Specialist searched the Specialised Register (April 2016) and the Cochrane Register of Studies (CENTRAL (2016

  18. Hypotension, lipodystrophy, and insulin resistance in generalized PPARγ-deficient mice rescued from embryonic lethality

    PubMed Central

    Duan, Sheng Zhong; Ivashchenko, Christine Y.; Whitesall, Steven E.; D’Alecy, Louis G.; Duquaine, Damon C.; Brosius, Frank C.; Gonzalez, Frank J.; Vinson, Charles; Pierre, Melissa A.; Milstone, David S.; Mortensen, Richard M.

    2007-01-01

    We rescued the embryonic lethality of global PPARγ knockout by breeding Mox2-Cre (MORE) mice with floxed PPARγ mice to inactivate PPARγ in the embryo but not in trophoblasts and created a generalized PPARγ knockout mouse model, MORE-PPARγ knockout (MORE-PGKO) mice. PPARγ inactivation caused severe lipodystrophy and insulin resistance; surprisingly, it also caused hypotension. Paradoxically, PPARγ agonists had the same effect. We showed that another mouse model of lipodystrophy was hypertensive, ruling out the lipodystrophy as a cause. Further, high salt loading did not correct the hypotension in MORE-PGKO mice. In vitro studies showed that the vasculature from MORE-PGKO mice was more sensitive to endothelial-dependent relaxation caused by muscarinic stimulation, but was not associated with changes in eNOS expression or phosphorylation. In addition, vascular smooth muscle had impaired contraction in response to α-adrenergic agents. The renin-angiotensin-aldosterone system was mildly activated, consistent with increased vascular capacitance or decreased volume. These effects are likely mechanisms contributing to the hypotension. Our results demonstrated that PPARγ is required to maintain normal adiposity and insulin sensitivity in adult mice. Surprisingly, genetic loss of PPARγ function, like activation by agonists, lowered blood pressure, likely through a mechanism involving increased vascular relaxation. PMID:17304352

  19. [Ocular hypotensive effect of alpha-adrenoceptor agonist and antagonist in the conscious pigmented rabbit].

    PubMed

    Moriwaki, Y; Iizuka, T; Nakamura, A; Nakata, K; Masaoka, Y; Ueda, T; Koide, R; Inatomi, M; Fukado, Y; Uchida, E

    1992-02-01

    It has been reported that some of the topically-used antiglaucomatics have a central ocular hypotensive effect. In this study, the influence of topical and intracerebroventricular (i.c.v.) administration of phenylephrine, clonidine, guanfacine, prazosin, yohimbine on the intraocular pressure (IOP) was investigated in the rabbit. Male pigmented rabbits were used throughout the experiments. For measurement of IOP, an applanation pneumatonograph was used. By unilateral topical administration of phenylephrine, an increase in IOP in the eye in which instillation was performed was observed. On the other hand, a slight decrease in IOP was observed by similar treatment of prazosin and yohimbine. No significant change of IOP in the contralateral eye was observed with these drugs. On the contrary, unilateral topical administration of clonidine or guanfacine decreased the IOP of both eyes. Furthermore, the decrease of IOP was more remarkable in the contralateral eye compared to the eye which received instillation. The IOP of both eyes was decreased in a dose-related fashion by i.c.v. administration of clonidine or guanfacine. The ocular hypotensive effects of clonidine were diminished by the pretreatment by i.c.v. administration with yohimbine. These results suggest that the ocular hypotensive effect of clonidine and guanfacine is due to their alpha 2-adrenoceptor stimulation in the central nervous system.

  20. Long-term safety of droxidopa in patients with symptomatic neurogenic orthostatic hypotension.

    PubMed

    Isaacson, Stuart; Vernino, Steven; Ziemann, Adam; Rowse, Gerald J; Kalu, Uwa; White, William B

    2016-10-01

    The long-term safety of droxidopa for the treatment of symptomatic neurogenic orthostatic hypotension in patients with Parkinson disease, pure autonomic failure, multiple system atrophy, or nondiabetic autonomic neuropathy was evaluated in a phase 3, multinational, open-label study in patients who previously participated in a double-blind, placebo-controlled clinical trial of droxidopa. A total of 350 patients received droxidopa 100 to 600 mg three times daily. Mean duration of droxidopa exposure was 363 days (range, 2-1133 days). Rates of serious adverse events (AEs), cardiac-related AEs, and supine hypertension were 24%, 5%, and 5%, respectively. Most AEs, including those of a cardiovascular nature, were not attributed by investigators to droxidopa. In this large cohort of patients with neurogenic orthostatic hypotension, droxidopa was well tolerated during long-term use. Copyright © 2016 The Author. Published by Elsevier Inc. All rights reserved.

  1. Long-Lasting Orthostatic Hypotension and Constipation After Celiac Plexus Block; A Case Report

    PubMed Central

    Yousefshahi, Fardin; Tahmasebi, Mamak

    2018-01-01

    This case report presents a 55 years old man, presented with abdominal pain and diagnosed with a metastatic pancreatic tumor, who developed long lasting orthostatic hypotension and constipation following a celiac plexus block. PMID:29868459

  2. Droxidopa and Reduced Falls in a Trial of Parkinson Disease Patients With Neurogenic Orthostatic Hypotension.

    PubMed

    Hauser, Robert A; Heritier, Stephane; Rowse, Gerald J; Hewitt, L Arthur; Isaacson, Stuart H

    2016-01-01

    Droxidopa is a prodrug of norepinephrine indicated for the treatment of orthostatic dizziness, lightheadedness, or the "feeling that you are about to black out" in adult patients with symptomatic neurogenic orthostatic hypotension caused by primary autonomic failure including Parkinson disease (PD). The objective of this study was to compare fall rates in PD patients with symptomatic neurogenic orthostatic hypotension randomized to droxidopa or placebo. Study NOH306 was a 10-week, phase 3, randomized, placebo-controlled, double-blind trial of droxidopa in PD patients with symptomatic neurogenic orthostatic hypotension that included assessments of falls as a key secondary end point. In this report, the principal analysis consisted of a comparison of the rate of patient-reported falls from randomization to end of study in droxidopa versus placebo groups. A total of 225 patients were randomized; 222 patients were included in the safety analyses, and 197 patients provided efficacy data and were included in the falls analyses. The 92 droxidopa patients reported 308 falls, and the 105 placebo patients reported 908 falls. In the droxidopa group, the fall rate was 0.4 falls per patient-week; in the placebo group, the rate was 1.05 falls per patient-week (prespecified Wilcoxon rank sum P = 0.704; post hoc Poisson-inverse Gaussian test P = 0.014), yielding a relative risk reduction of 77% using the Poisson-inverse Gaussian model. Fall-related injuries occurred in 16.7% of droxidopa-treated patients and 26.9% of placebo-treated patients. Treatment with droxidopa appears to reduce falls in PD patients with symptomatic neurogenic orthostatic hypotension, but this finding must be confirmed.

  3. Droxidopa and Reduced Falls in a Trial of Parkinson Disease Patients With Neurogenic Orthostatic Hypotension

    PubMed Central

    Hauser, Robert A.; Heritier, Stephane; Rowse, Gerald J.; Hewitt, L. Arthur; Isaacson, Stuart H.

    2016-01-01

    Objectives Droxidopa is a prodrug of norepinephrine indicated for the treatment of orthostatic dizziness, lightheadedness, or the “feeling that you are about to black out” in adult patients with symptomatic neurogenic orthostatic hypotension caused by primary autonomic failure including Parkinson disease (PD). The objective of this study was to compare fall rates in PD patients with symptomatic neurogenic orthostatic hypotension randomized to droxidopa or placebo. Methods Study NOH306 was a 10-week, phase 3, randomized, placebo-controlled, double-blind trial of droxidopa in PD patients with symptomatic neurogenic orthostatic hypotension that included assessments of falls as a key secondary end point. In this report, the principal analysis consisted of a comparison of the rate of patient-reported falls from randomization to end of study in droxidopa versus placebo groups. Results A total of 225 patients were randomized; 222 patients were included in the safety analyses, and 197 patients provided efficacy data and were included in the falls analyses. The 92 droxidopa patients reported 308 falls, and the 105 placebo patients reported 908 falls. In the droxidopa group, the fall rate was 0.4 falls per patient-week; in the placebo group, the rate was 1.05 falls per patient-week (prespecified Wilcoxon rank sum P = 0.704; post hoc Poisson-inverse Gaussian test P = 0.014), yielding a relative risk reduction of 77% using the Poisson-inverse Gaussian model. Fall-related injuries occurred in 16.7% of droxidopa-treated patients and 26.9% of placebo-treated patients. Conclusions Treatment with droxidopa appears to reduce falls in PD patients with symptomatic neurogenic orthostatic hypotension, but this finding must be confirmed. PMID:27332626

  4. Methylene blue, midodrine, and pseudoephedrine: a review of alternative agents for refractory hypotension in the intensive care unit.

    PubMed

    Van Berkel, Megan A; Fuller, Laura A; Alexandrov, Anne W; Jones, G Morgan

    2015-01-01

    Hypotensive episodes are common among patients in the intensive care unit and can lead to multiorgan failure if uncontrolled. Fluid administration and continuous infusion of vasoactive agents are frequently used for management of hypotension; however, both therapies may be associated with adverse effects including pulmonary edema and tissue necrosis. In addition, availability of these first-line agents has been impacted by the increasing occurrence of drug shortages. Methylene blue, pseudoephedrine, and midodrine have been considered potential alternatives to standard therapy. These agents may not only be used when first-line agents are unavailable due to shortages, but they may also aid in reducing the cumulative dose of other vasoactive agents used. The purpose of this review was to discuss strategies for the safe and effective use of methylene blue, pseudoephedrine, and midodrine for the treatment of hypotension in the critically ill.

  5. Harmane produces hypotension following microinjection into the RVLM: possible role of I1-imidazoline receptors

    PubMed Central

    Musgrave, I F; Badoer, E

    2000-01-01

    The β-carboline, harmane (0.1–1.0 nmol) produces dose dependent hypotension when microinjected unilaterally into the rostral ventrolateral medulla (RVLM) of the anaesthetized rat. The potency of harmane on blood pressure is similar to that of the imidazoline, clonidine. The hypotensive effects of both clonidine and harmane are reversed by microinjection of the relatively I1-receptor selective antagonist efaroxan (20 nmol). These results are consistent with harmane acting at an I1-receptor in the RVLM. This is the first report of an endogenous ligand for I1-receptors that has central effects on blood pressure. PMID:10725251

  6. [Can Glasgow-Blatchford Score and Pre-endoscopic Rockall Score Predict the Occurrence of Hypotension in Initially Normotensive Patients with Non-variceal Upper Gastrointestinal Bleeding?].

    PubMed

    Kim, June Sung; Ko, Byuk Sung; Son, Chang Hwan; Ahn, Shin; Seo, Dong Woo; Lee, Yoon Seon; Lee, Jae Ho; Oh, Bum Jin; Lim, Kyoung Soo; Kim, Won Young

    2016-01-25

    The aim of this study was to identify the ability of Glasgow-Blatchford score (GBS) and pre-endoscopic Rockall score (pre-E RS) to predict the occurrence of hypotension in patients with non-variceal upper gastrointestinal bleeding who are initially normotensive at emergency department. Retrospective observational study was conducted at Asan Medical Center emergency department (ED) in patients who presented with non-variceal upper gastrointestinal bleeding from January 1, 2011 to December 31, 2013. Study population was divided according to the development of hypotension, and demographics, comorbidities, and laboratory findings were compared. GBS and pre-E RS were estimated to predict the occurrence of hypotension. A total of 747 patients with non-variceal upper gastrointestinal bleeding were included during the study period, and 120 (16.1%) patients developed hypotension within 24 hours after ED admission. The median values GBS and pre-E RS were statistically different according to the occurrence of hypotension (8.0 vs. 10.0, 2.0 vs. 3.0, respectively; p<0.001). In the receiver operating characteristic curve analysis of hypotension development, the area under the curve of GBS and pre-E RS were 66% and 64%, respectively. The sensitivity and the specificity of GBS using optimal cut-off value were 81% and 46%, respectively, while those based on the pre-E RS were 74% and 46%, respectively. GBS and pre-E RS were both not sufficient for predicting the occurrence of hypotension in non-variceal upper gastrointestinal bleeding. Development of other scoring systems are needed.

  7. Pediatric Diabetic Ketoacidosis With Hypotensive Shock and Rash-An Unusual Presentation.

    PubMed

    Pasternak, Yehonatan; Niv, Omer; Waisman, Yehezkel Hezi

    2018-05-15

    We describe a previously healthy adolescent boy who presented with respiratory distress, hypotensive shock, and a diffuse erythematous rash. The final diagnosis was diabetic ketoacidosis. Caregivers should be alert to this unusual combination of symptoms in the emergency department setting in order to improve the recognition and management of children with new-onset diabetes.

  8. Recurrent syncope, orthostatic hypotension and volatile hypertension: think outside the box.

    PubMed

    Aung, Thein; Fan, Wuqiang; Krishnamurthy, Mahesh

    2013-01-01

    The baroreceptors in the neck and aortic arch are important regulators of sudden blood pressure changes. They are innervated by CN IX and X and synapse in the brainstem. Baroreceptor failure is an under-recognized cause of recurrent syncope, orthostatic hypotension, and volatile hypertension, which is refractory to and may in fact worsen with conventional treatments. Baroreflex failure can be the result of neck and chest radiation, head and neck surgery, and cerebrovascular accidents involving the brainstem nuclei. The management of baroreflex failure is a challenge since patient education, lifestyle changes, and family support are extremely important in managing blood pressure. Leg exercises and Thrombo-Embolic Deterrent Stockings (TED) stockings are important in treating orthostatic hypotension. Clonidine is the antihypertensive of choice for supine hypertension. Low-dose benzodiazepines are helpful in suppressing sympathetic surges. We have encountered two patients with baroreflex failure after chemotherapy and radiation to the neck or upper chest. Temporal relationship between symptoms onset and the history of head, neck, and upper chest radiation or trauma is important in reaching a diagnosis.

  9. Hypoxia and hypotension in patients intubated by physician staffed helicopter emergency medical services - a prospective observational multi-centre study.

    PubMed

    Sunde, Geir Arne; Sandberg, Mårten; Lyon, Richard; Fredriksen, Knut; Burns, Brian; Hufthammer, Karl Ove; Røislien, Jo; Soti, Akos; Jäntti, Helena; Lockey, David; Heltne, Jon-Kenneth; Sollid, Stephen J M

    2017-07-11

    The effective treatment of airway compromise in trauma and non-trauma patients is important. Hypoxia and hypotension are predictors of negative patient outcomes and increased mortality, and may be important quality indicators of care provided by emergency medical services. Excluding cardiac arrests, critical trauma and non-trauma patients remain the two major groups to which helicopter emergency medical services (HEMS) are dispatched. Several studies describe the impact of pre-hospital hypoxia or hypotension on trauma patients, but few studies compare this in trauma and non-trauma patients. The primary aim was to describe the incidence of pre-hospital hypoxia and hypotension in the two groups receiving pre-hospital tracheal intubation (TI) by physician-staffed HEMS. Data were collected prospectively over a 12-month period, using a uniform Utstein-style airway template. Twenty-one physician-staffed HEMS in Europe and Australia participated. We compared peripheral oxygen saturation and systolic blood pressure before and after definitive airway management. Data were analysed using Cochran-Mantel-Haenszel methods and mixed-effects models. Eight hundred forty three trauma patients and 422 non-trauma patients receiving pre-hospital TI were included. Non-trauma patients had significantly lower predicted mean pre-intervention SpO 2 compared to trauma patients. Post-intervention and admission SpO 2 for the two groups were comparable. However, 3% in both groups were still hypoxic at admission. For hypotension, the differences between the groups were less prominent. However, 9% of trauma and 10% of non-trauma patients were still hypotensive at admission. There was no difference in short-term survival between trauma (97%) and non-trauma patients (95%). Decreased level of consciousness was the most frequent indication for TI, and was associated with increased survival to hospital (cOR 2.8; 95% CI: 1.4-5.4). Our results showed that non-trauma patients had a higher incidence of

  10. Pilot Study: Colostomy and Urine Collection Protocol for Investigating Potential Inciting Causes of Hen Diuresis Syndrome.

    PubMed

    Jones, Kelli; Turner, Bradley; Brandão, João; Hubbard, Sue Ann; Magee, Danny; Baughman, Brittany; Wills, Robert; Tully, Thomas

    2015-06-01

    Hen diuresis syndrome has emerged over the past 5 yr as a significant cause of mortality in the U.S. broiler breeder industry. The condition affects hens in production and is characterized by transient muscle weakness in the vent region, transient diuresis, and often urate deposits on the skin below the vent. Affected hens are often seen straining to lay an egg, which suggests oviduct contraction is also impaired. Related hen mortality, often reaching 1% or more a week, is believed to be primarily the result of male aggression of the vent region (Turner et al., "Investigating Causes of Excessive Urate Production in Broiler Breeder Hens Associated with Peritonitis and Cannibalism Mortality," Oral Presentation at The American Association of Avian Pathologists Annual Meeting, p. 139, 2010). The exact association between the cause of mortality and this syndrome is unknown, but it may be the consequence of transient partial to full oviduct prolapse, which predisposes or stimulates cannibalism and aggression. Based on unpublished work done prior to this study (Turner et al., ibid.), the evidence suggests the underlying problem is metabolic. We feel that urine collection and analysis is an essential component to understanding this condition. This study serves as a pilot study for future investigations that attempt to identify the nature and cause of the metabolic disturbance through paired urine and serum collection and analysis. For the purpose of this study, a small sample of 10 affected and 10 unaffected birds was used for sample collection. In order to collect pure urine, the birds were surgically colostomized. Colostomy did prove to be a useful means of collecting urine free of feces, and for the purposes of our study it yielded adequate urine samples for analysis. There were statistically relevant urine values observed. Affected birds had a higher presence of blood in the urine, a lower uric acid excretion rate (mg/hr), higher concentration (mEq/L) of urine Na+, and

  11. CHHIPS (Controlling Hypertension and Hypotension Immediately Post-Stroke) Pilot Trial: rationale and design.

    PubMed

    Potter, J; Robinson, T; Ford, G; James, M; Jenkins, D; Mistri, A; Bulpitt, C; Drummond, A; Jagger, C; Knight, J; Markus, H; Beevers, G; Dewey, M; Lees, K; Moore, A; Paul, S

    2005-03-01

    High and low blood pressure (BP) levels are common following acute stroke, with up to 60% of patients being hypertensive (SBP > 160 mmHg) and nearly 20% having relative hypotension (SBP < or = 140 mmHg), within the first few hours of ictus, both conditions being associated with an adverse prognosis. At present, the optimum management of blood pressure in the immediate post-stroke period is unclear. The primary aim of the Controlling Hypertension and Hypotension Immediately Post-Stroke (CHHIPS) Pilot Trial is to assess whether hypertension and relative hypotension, manipulated therapeutically in the first 24 h following acute stroke, affects short-term outcome measures. The CHHIPS Pilot Trial is a UK based multi-centre, randomized, double-blind, placebo-controlled, titrated dose trial. Acute stroke and medical units in teaching and district general hospitals, in the UK. The CHHIPS Pilot Study aims to recruit 2050 patients, with clinically suspected stroke, confirmed by brain imaging, who have no compelling indication or contraindication for BP manipulation. The primary outcome measure will be the effects of acute pressor therapy (initiated < or = 12 h from stroke onset) or depressor therapy (started < or = 24 h post-ictus) on death and dependency at 14 days post-stroke. Secondary outcome measures will include the influence of therapy on early neurological deterioration, the effectiveness of treatment in manipulating BP levels, the influence of time to treatment and stroke type on response and a cost-effectiveness analysis.

  12. Hemodynamic Effects of Midodrine After Space Flight in Astronauts Without Orthostatic Hypotension

    NASA Technical Reports Server (NTRS)

    Platts, Steven H.; Ziegler, Michael G.; Waters, Wendy W.; Meck, Janice V.

    2006-01-01

    Orthostatic hypotension and presyncope are common and potentially serious risks for astronauts returning from space. Susceptible subjects fail to generate an adequate adrenergic response to upright posture. The -1 adrenergic agonist, midodrine, may be an effective countermeasure. We tested the hypothesis that midodrine would have no negative hemodynamic effect on healthy astronauts returning from space. Five male astronauts participated in preflight and postflight tilt testing on a control flight as well as on the test flights, where midodrine (10 mg, orally) was administered after landing, approximately 1 hour before testing. None of these astronauts exhibited orthostatic hypotension or presyncope before or after either flight. Midodrine did not cause any untoward reactions in these subjects before or after flight, in fact a modest beneficial effect was seen on postflight tachycardia (p=0.036). These data show that midodrine protected against post-spaceflight increases in heart rate, without having any adverse hemodynamic effects on non-presyncopal, male astronauts. Among these subjects, midodrine was a safe cardiovascular countermeasure.

  13. Population pharmacokinetics of unbound hydrocortisone in critically ill neonates and infants with vasopressor-resistant hypotension.

    PubMed

    Vezina, Heather E; Ng, Chee M; Vazquez, Delia M; Barks, John D; Bhatt-Mehta, Varsha

    2014-07-01

    To determine the population pharmacokinetics of unbound hydrocortisone in critically ill neonates and infants receiving IV hydrocortisone for treatment of vasopressor-resistant hypotension and to identify patient-specific sources of pharmacokinetic variability. Prospective observational cohort study. Level 3 neonatal ICU. Sixty-two critically ill neonates and infants receiving IV hydrocortisone as part of standard of care for the treatment of vasopressor-resistant hypotension: median gestational age 28 weeks (range, 23-41), median weight 1.2 kg (range, 0.5-4.4), and 29 females. None. Unbound baseline cortisol and postdose hydrocortisone concentrations measured from blood samples being drawn for routine laboratory tests. A one-compartment model best described the data. Allometric weight and postmenstrual age were significant covariates on unbound hydrocortisone clearance and volume of distribution. Final population estimates for clearance, volume of distribution, and baseline cortisol concentration were 20.2 L/hr, 244 L, and 1.37 ng/mL, respectively. Using the median weight and postmenstrual age of our subjects (i.e., 1.2 kg and 28 wk) in the final model, the typical unbound hydrocortisone clearance and volume of distribution were 1.0 L/hr and 4.2 L, respectively. The typical half-life for unbound hydrocortisone was 2.9 hours. A sharp and continuous increase in unbound hydrocortisone clearance was observed at 35 weeks postmenstrual age. We report the first pharmacokinetic data for unbound hydrocortisone, the pharmacologically active moiety, in critically ill neonates and infants with vasopressor-resistant hypotension. Unbound hydrocortisone clearance increased with body weight and was faster in children with an older postmenstrual age. Unbound hydrocortisone clearance increased sharply at 35 weeks postmenstrual age and continued to mature thereafter. This study lays the groundwork for evaluating unbound hydrocortisone exposure-response relationships and drawing

  14. An enantiomerically pure formulation of esmolol attenuates hypotension and preserves heart rate control in dogs.

    PubMed

    McKee, Jeffrey S; Rabinow, Barrett E; Daller, Justin R; Brooks, Benjamin D; Baumgartner, Bernhard; Rohatgi, Priyanka

    2014-12-01

    Esmolol is marketed as a racemate (RS-esmolol) with hypotension being the most frequently reported adverse event. Previously, it has been shown that the S-enantiomer (S-esmolol) possesses all of the heart rate (HR) control. The authors studied whether S-esmolol alone mitigates hypotension at similar degrees of HR control compared with RS-esmolol. The effects of RS- and S-esmolol on blood pressure (BP) were compared at multiple infusion rates producing similar HR control in dogs (N=21). Differences in BP were further interrogated by monitoring global cardiovascular function and included the R-enantiomer (R-esmolol) (N=3). S-esmolol at half the rate (μg kg min) of RS-esmolol provided the same degree of HR control over all infusion rates. RS-esmolol lowered BP by 3, 6, 11, 20, and 38 mmHg at 90, 300, 600, 1,000, and 2,000 μg kg min, compared with 2, 4, 5, 10, and 16 mmHg at 45, 150, 300, 500, and 1,000 μg kg min for S-esmolol. Decreased BP with RS-esmolol was attributed to decreases in left ventricular developed pressure (LVDP) (-34 mmHg), LVdP/dt+max (-702 mmHg/s), and cardiac output (-1 l/min). R-esmolol also decreased BP (-10 mmHg), LVDP (-10 mmHg), LVdP/dt+max (-241 mmHg/s), and cardiac output (to -0.2 l/min). S-esmolol reversed these trends toward pre-esmolol values by increasing BP (+13 mmHg), LVDP (+12 mmHg), LVdP/dt+max (+76 mmHg/s), and cardiac output (+0.4 l/min). R-enantiomer provided no HR control, but contributed to the hypotension with RS-esmolol, which appears to be due to negative inotropy. Thus, an S-enantiomer formulation of esmolol may provide similar HR control with less hypotension.

  15. Comparison of hypotensive, diuretic and renal effects between cladodes of Opuntia ficus-indica and furosemide.

    PubMed

    Bakour, Meryem; Al-Waili, Noori; El-Haskoury, Redouan; El-Menyiy, Nawal; Al-Waili, Thia; Al-Waili, Ali; Lyoussi, Badiaa

    2017-09-01

    To investigate the diuretic, hypotensive and renal effect of Opuntia ficus-indica in two different species in oral and intravenous administration. Diuretic activity was evaluated in rats with the plant cladode gel and aqueous extract administrated orally, and was evaluated in rabbits with plant extract administered intravenously. Single and repeated doses of cladode gel or aqueous extract of cladode were tested. Urine volume and blood and urine creatinine, sodium and potassium were measured, and creatinine clearance was calculated. The hypotensive effect of lyophilized extract of cladode was evaluated in rabbits. Two polyethylene PE50 catheters were used: one in the jugular vein for the infusion of the plant extract and the other in the carotid for the evaluation of the arterial pressure. The cladode gel or aqueous extract increased urine volume, creatinine clearance and urinary excretion of sodium and potassium without significant effect on serum creatinine or blood urea. Furosemide, gel and aqueous extract of cladode insignificantly lowered plasma potassium in rats. Intravenous administration of the lyophilized extract caused a significant decrease in mean arterial pressure in rabbits with a significant increase in urine volume and urine sodium and potassium; the effect was dose dependent. Intravenous administration of lyophilized extract did not affect plasma sodium or potassium. Gel and aqueous extract of Opuntia ficus-indica cladode have a significant diuretic effect on rats, and the lyophilized extract has a diuretic and hypotensive effect on normotensive rabbits without deterioration in renal function test. Additional studies on active ingredients are essential to pave the way for clinical studies on diuretic and hypotensive effect of the plant. Copyright © 2017 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.

  16. Characterization of Human Torso Vascular Morphometry in Normotensive and Hypotensive Trauma Patients

    DTIC Science & Technology

    2015-07-01

    Aorta Wall Measures Merged for Analysis Landmarks & User-aided Segmentation 5cm Volume...with Centerline Measures AORTA PROCESSING VENA CAVA PROCESSING Basic Morphomics Scan Identification Aorta Centerline Segmented Aorta and Vena...Analysis 49 Data Presentation Aorta  Radius  Popula/on       Normotensive   Hypotensive  

  17. Sympatho-vagal balance, as quantified by ANSindex, predicts post spinal hypotension and vasopressor requirement in parturients undergoing lower segmental cesarean section: a single blinded prospective observational study.

    PubMed

    Prashanth, Anitha; Chakravarthy, Murali; George, Antony; Mayur, Rohini; Hosur, Rajathadri; Pargaonkar, Sumant

    2017-08-01

    Hypotension subsequent to spinal anesthesia occurs in a significant number of parturients undergoing lower segment caesarian section. Currently available methods to predict the incidence of hypotension, its severity and the outcome are sub-optimal. Many workers have used basal heart rate as one of the predictors. But using this method it is not possible to objectively analyze and predict the extent and severity of hypotension. We used an equipment measuring the level of sympatho-vagal balance, ANSiscope™, which derives these values from computed value of RR interval variability. We made a single measure of the value which was blinded to the patient and the anesthesiologist. We studied one hundred eight patients who underwent lower segment caesarian section under spinal anesthesia and found the variability of preoperative ANSindex (% activity displayed by the equipment) from 9 to 65 %. Higher ANSindex value was significantly associated with post spinal hypotension (p 0.017). A value of 24 % indicated the critical level above which hypotension appeared commonly. The ANSindex value might help anesthesiologist to anticipate and prepare for hypotension that is likely to ensue.

  18. Modulation of cardiac autonomic tone in non-hypotensive hypovolemia during blood donation.

    PubMed

    Yadav, Kavita; Singh, Akanksha; Jaryal, Ashok Kumar; Coshic, Poonam; Chatterjee, Kabita; Deepak, K K

    2017-08-01

    Non-hypotensive hypovolemia, observed during mild haemorrhage or blood donation leads to reflex readjustment of the cardiac autonomic tone. In the present study, the cardiac autonomic tone was quantified using heart rate and blood pressure variability during and after non-hypotensive hypovolemia of blood donation. 86 voluntary healthy male blood donors were recruited for the study (age 35 ± 9 years; weight 78 ± 12 kg; height 174 ± 6 cms). Continuous lead II ECG and beat-to-beat blood pressure was recorded before, during and after blood donation followed by offline time and frequency domain analysis of HRV and BPV. The overall heart rate variability (SDNN and total power) did not change during or after blood donation. However, there was a decrease in indices that represent the parasympathetic component (pNN50 %, SDSD and HF) while an increase was observed in sympathetic component (LF) along with an increase in sympathovagal balance (LF:HF ratio) during blood donation. These changes were sustained for the period immediately following blood donation. No fall of blood pressure was observed during the period of study. The blood pressure variability showed an increase in the SDNN, CoV and RMSSD time domain measures in the post donation period. These results suggest that mild hypovolemia produced by blood donation is non-hypotensive but is associated with significant changes in the autonomic tone. The increased blood pressure variability and heart rate changes that are seen only in the later part of donation period could be because of the progressive hypovolemia associated parasympathetic withdrawal and sympathetic activation that manifest during the course of blood donation.

  19. Feasibility of intermittent back-filtrate infusion hemodiafiltration to reduce intradialytic hypotension in patients with cardiovascular instability: a pilot study.

    PubMed

    Koda, Yutaka; Aoike, Ikuo; Hasegawa, Shin; Osawa, Yutaka; Nakagawa, Yoichi; Iwabuchi, Fumio; Iwahashi, Chikara; Sugimoto, Tokuichiro; Kikutani, Toshihiko

    2017-04-01

    Intradialytic hypotension (IDH) is one of the major problems in performing safe hemodialysis (HD). As blood volume depletion by fluid removal is a major cause of hypotension, careful regulation of blood volume change is fundamental. This study examined the effect of intermittent back-filtrate infusion hemodiafiltration (I-HDF), which modifies infusion and ultrafiltration pattern. Purified on-line quality dialysate was intermittently infused by back filtration through the dialysis membrane with a programmed dialysis machine. A bolus of 200 ml of dialysate was infused at 30 min intervals. The volume infused was offset by increasing the fluid removal over the next 30 min by an equivalent amount. Seventy-seven hypotension-prone patients with over 20-mmHg reduction of systolic blood pressure during dialysis or intervention-requirement of more than once a week were included in the crossover study of 4 weeks duration for each modality. In a total of 1632 sessions, the frequency of interventions, the blood pressure, and the pulse rate were documented. During I-HDF, interventions for symptomatic hypotension were reduced significantly from 4.5 to 3.0 (per person-month, median) and intradialytic systolic blood pressure was 4 mmHg higher on average. The heart rate was lower during I-HDF than HD in the later session. Older patients and those with greater interdialytic weight gain responded to I-HDF. I-HDF could reduce interventions for IDH. It is accompanied with the increased intradialytic blood pressure and the less tachycardia, suggesting less sympathetic stimulation occurs. Thus, I-HDF could be beneficial for some hypotension-prone patients. 000013816.

  20. Controlled hypotension versus normotensive resuscitation strategy for people with ruptured abdominal aortic aneurysm.

    PubMed

    Moreno, Daniel H; Cacione, Daniel G; Baptista-Silva, Jose Cc

    2018-06-13

    An abdominal aortic aneurysm (AAA) is the pathological enlargement of the aorta and can develop in both men and women. Progressive aneurysm enlargement can lead to rupture. The rupture of an AAA is frequently fatal and accounts for the death from haemorrhagic shock of at least 45 people per 100,000 population. The outcome of people with ruptured AAA varies among countries and healthcare systems, with mortality ranging from 53% to 90%. Definitive treatment for ruptured AAA includes open surgery or endovascular repair. The management of haemorrhagic shock is crucial for the person's outcome and aims to restore organ perfusion and systolic blood pressure above 100 mmHg through immediate and aggressive fluid replacement. This rapid fluid replacement is known as the normotensive resuscitation strategy. However, evidence suggests that infusing large volumes of cold fluid causes dilutional and hypothermic coagulopathy. The association of these factors may exacerbate bleeding, resulting in a 'lethal triad' of hypothermia, acidaemia, and coagulopathy. An alternative to the normotensive resuscitation strategy is the controlled (permissive) hypotension resuscitation strategy, with a target systolic blood pressure of 50 mmHg to 100 mmHg. The principle of controlled or hypotensive resuscitation has been used in some management protocols for endovascular repair of ruptured AAA. It may be beneficial in preventing blood loss by avoiding the clot disruption caused by the rapid increase in systolic blood pressure; avoiding dilution of clotting factors, platelets and fibrinogen; and by avoiding the temperature decrease that inhibits enzyme activity involved in platelet and clotting factor function. This is an update of a review first published in 2016. To compare the effects of controlled (permissive) hypotension resuscitation and normotensive resuscitation strategies for people with ruptured AAA. The Cochrane Vascular Information Specialist searched the Specialised Register (August

  1. Hypotensive anesthesia with esmolol. Assessment of hemodynamics, consumption of anesthetic drugs, and recovery.

    PubMed

    Gökçe, Biricik M; Karabiyik, Lale; Karadenizli, Yener

    2009-06-01

    To assess the effect of esmolol added to propofol-remifentanil combination for hypotensive anesthesia on hemodynamic conditions, consumption of anesthetic drugs, and recovery, during elective septorhinoplasty. This prospective, randomized study was carried out at Gazi University, Faculty of Medicine, Ankara, Turkey in 2005. Following Institutional Ethical Committee approval, 40 American Society of Anesthesiologists (ASA) I patients were divided into 2 equal groups group remifentanil infusion RP and group esmolol infusion (RP-E). After anesthesia induction with propofol (2-2.5 mg/kg), the mean arterial pressure was aimed to be between 50 mm Hg and 65 mm Hg for controlled hypotensive anesthesia in both groups. In group RP, a remifentanil infusion of 0.1-0.5 microg/kg/min was titrated, following a bolus of 1 microg/kg; for group RP-E, an esmolol infusion of 100-300 mg/kg/min was titrated, following a bolus of 500 microg/kg; to achieve a target blood pressure. In addition, propofol was infused according to depth of anesthesia to maintain anesthesia in both groups. Electrocardiography, heart rate, blood pressure, cardiac output, and consumption of anesthetic drugs were recorded. Postoperatively, recovery times, visual analog pain scores, and side effects were observed. The decrease in the intraoperative heart rate was more significant in group RP-E than in group RP. The remifentanil consumption was much lower in group RP-E. The recovery times were similar in both groups. Addition of esmolol to propofol-remifentanil combination leads to a decrease in remifentanil consumption, without a decrease in cardiac output during hypotensive anesthesia.

  2. Antagonistic effects of atipamezole and yohimbine on medetomidine-induced diuresis in healthy dogs

    PubMed Central

    Talukder, Md. Hasanuzzaman; Hikasa, Yoshiaki; Takahashi, Hajime; Sato, Kanako; Matsuu, Aya

    2009-01-01

    This study aimed to investigate and compare the antagonistic effects of atipamezole and yohimbine on medetomidine-induced diuresis in healthy dogs. Five dogs were used repeatedly in each of 8 groups. One group was not medicated. Dogs in the other groups received 20 μg/kg of medetomidine intramuscularly and, 0.5 h later, saline (as the control injection), 50, 100, or 300 μg/kg of atipamezole, or 50, 100, or 300 μg/kg of yohimbine intramuscularly. Urine and blood samples were taken 11 times over 24 h for measurement of the following: urine volume, specific gravity, and creatinine concentration; urine and plasma osmolality; urine and plasma concentrations of electrolytes and arginine vasopressin (AVP); and the plasma concentration of atrial natriuretic peptide (ANP). Both atipamezole and yohimbine antagonized the diuretic effect of medetomidine, inhibiting medetomidine-induced decreases in urine specific gravity, osmolality, and concentrations of creatinine, sodium, potassium, chloride, and AVP and reversing both the medetomidine-induced increase in plasma concentrations of sodium, potassium, and chloride and the medetomidine-induced decrease in the plasma AVP concentration. Atipamezole significantly stimulated ANP release. The antidiuretic action of yohimbine was more potent than that of atipamezole but was not dose-dependent, in contrast to the action of atipamezole. The effects of these drugs may not be due only to actions mediated by α2-adrenoceptors. PMID:20046627

  3. Neonatal capsaicin treatment impairs vasopressin-mediated blood pressure recovery following acute hypotension.

    PubMed Central

    Bennett, T.; Gardiner, S. M.

    1984-01-01

    Rats were treated with a single injection of either capsaicin (50 mg kg-1 s.c.) or vehicle on day 2 after birth. When the animals were adult, they were challenged with osmotic (water deprivation) and haemodynamic (acute hypotension) stimuli that normally evoke vasopressin release. Capsaicin-treated and vehicle-injected rats showed similar body weight losses and plasma osmolalities following 48 h of water deprivation. Thus it appears that neonatal treatment with capsaicin does not impair the antidiuretic response to plasma hyperosmolality. Following acute ganglion blockade in the presence of angiotensin converting enzyme inhibition, there was some recovery of blood pressure in the vehicle-injected rats, but recovery was significantly (P less than 0.001) less in the capsaicin-treated animals. The recovery may be attributed to vasopressin since it was abolished by an antagonist selective for the pressor action of the peptide (d(CH2)5DAVP). These results suggest that neonatal treatment with capsaicin impairs vasopressin-mediated recovery of blood pressure following acute hypotension. The possible involvement of baro- or chemoreceptor afferents is discussed. PMID:6704593

  4. Increased incidence of clinical hypotension with etomidate compared to ketamine for intubation in septic patients: A propensity matched analysis.

    PubMed

    Van Berkel, Megan A; Exline, Matthew C; Cape, Kari M; Ryder, Lindsay P; Phillips, Gary; Ali, Naeem A; Doepker, Bruce A

    2017-04-01

    This study compared the incidence of clinical hypotension between ketamine and etomidate within a 24 hour period following endotracheal intubation. This single-center, retrospective propensity-matched cohort study included septic patients admitted to our medical intensive care unit who received either etomidate or ketamine for intubation. Clinical hypotension was defined as any one of the following: mean arterial pressure (MAP) decrease >40% compared to baseline and MAP <70 mmHg, MAP <60 mmHg, initiation of a vasopressor, or increase to >30% of the initial vasopressor dose. Patients were matched based on propensity scores determined by demographics and baseline characteristics. A total of 384 (200 etomidate and 184 ketamine) patients were included for analysis with 230 patients (115 in each group) matched. Clinical hypotension was less prevalent in patients who received ketamine as compared to etomidate [51.3% vs. 73% (odds ratio=0.39, 95% confidence interval=0.22-0.67, P=.001]. The etomidate group experienced significantly lower MAPs at time periods 6.1-12 hours (65.1 mmHg vs. 69.3 mmHg, P=.01) and 12.1-24 hours (63.9 mmHg vs. 68.4 mmHg, P=.003). Ketamine was associated with a lower incidence of clinical hypotension within the 24 hour period following endotracheal intubation in septic patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Induction of rat hepatic aryl sulfotransferase (SULT1A1) gene expression by triamcinolone acetonide: impact on minoxidil-mediated hypotension.

    PubMed

    Duanmu, Z; Dunbar, J; Falany, C N; Runge-Morris, M

    2000-05-01

    The hypotensive agent minoxidil (6-imino-1, 2-dihydro-1-hydroxy-2-imino-4-piperidinopyrimidine) depends upon aryl sulfotransferase (SULT1)-catalyzed sulfation for its bioactivation. Previous reports suggest that glucocorticoids induce class-specific SULT1 and isoform-specific SULT1A1 gene expression in rat liver. In the present study, rats were treated with the glucocorticoid triamcinolone acetonide (TA, 5 mg/kg/day i.p. x 3 days) or its vehicle, 2% Tween-20, prior to minoxidil, and subsequent effects on mean arterial pressure (MAP), heart rate (HR), and hepatic SULT1 gene expression were characterized. Minoxidil treatment (1.5 mg/kg) resulted in a steady decline in MAP values of 16.3 to 18.6% relative to basal control levels at 35 to 60 min following minoxidil injection. Pentachlorophenol (PCP, 40 micromol/kg i.p.), an inhibitor of SULT1 enzyme activity, effectively ablated the hypotensive effects of minoxidil. By contrast, pretreatment with TA significantly enhanced minoxidil-induced hypotension. Relative to vehicle-treated controls, TA-treated rats displayed a steeper rate of decline in MAP and more profound levels of hypotension with decreases in MAP following minoxidil administration of 27.8%. TA also produced significant increases in hepatic SULT1 mRNA expression (of 271%) and SULT1A1 immunoreactive protein levels (of 273%), relative to vehicle-treated controls. These results provide physiological evidence to support the biological relevance of SULT1A1 induction by glucocorticoids. The data indicate that steroid treatment induces SULT1A1 gene expression and, as a consequence, accentuates the hypotensive effects of minoxidil. Copyright 2000 Academic Press.

  6. Two syringe spinal anesthesia technique for cesarean section: A controlled randomized study of a simple way to achieve more satisfactory block and less hypotension.

    PubMed

    Keera, Amr Aly Ismail; Elnabtity, Ali Mohamed Ali

    2016-01-01

    Multiple trials have been tried to prevent hypotension during spinal anesthesia. However, the drug choice and mode of administration is still a matter of debate. To compare the outcome of spinal injection of hyperbaric bupivacaine and fentanyl separately to standard injection of mixed fentanyl with hyperbaric bupivacaine. A randomized, controlled clinical trial. One hundred twenty-four parturient scheduled for elective cesarean section were randomly allocated into two groups, each 62 parturient: Group M received spinal anesthesia using 10 mg bupivacaine 0.5% premixed with 25 μg fentanyl in the same syringe and Group S received 25 μg fentanyl in one syringe and 10 mg bupivacaine 0.5% without barbotage in a second syringe. Patients with intraoperative pain that was controllable without the need for a shift to general anesthesia was significantly lower in Group S (3.2%) than in Group M (16.1%). The frequency of hypotension was significantly lower in Group S compared to Group M (P < 0.05). Time till the onset of sensory block was nonsignificantly shorter with nonsignificantly higher mean level of maximal sensory block in Group S compared to Group M (P > 0.05). There was no significant difference in the time till occurrence of hypotension, duration of hypotension, mean dose of ephedrine used for the treatment of hypotension and frequency of patients developed itching between the groups (P > 0.05). Separate intrathecal injection of fentanyl and hyperbaric bupivacaine provided a significant improvement in the quality of sensory block and significant reduction of the frequency of hypotension compared to injection of mixed medications.

  7. 46 CFR 108.661 - Unit markings: Draft marks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Unit markings: Draft marks. 108.661 Section 108.661... AND EQUIPMENT Equipment Markings and Instructions § 108.661 Unit markings: Draft marks. (a) Each unit must have draft marks for each foot of immersion— (1) If the unit is a surface unit, on both the port...

  8. 46 CFR 108.661 - Unit markings: Draft marks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Unit markings: Draft marks. 108.661 Section 108.661... AND EQUIPMENT Equipment Markings and Instructions § 108.661 Unit markings: Draft marks. (a) Each unit must have draft marks for each foot of immersion— (1) If the unit is a surface unit, on both the port...

  9. 46 CFR 108.661 - Unit markings: Draft marks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Unit markings: Draft marks. 108.661 Section 108.661... AND EQUIPMENT Equipment Markings and Instructions § 108.661 Unit markings: Draft marks. (a) Each unit must have draft marks for each foot of immersion— (1) If the unit is a surface unit, on both the port...

  10. 46 CFR 108.661 - Unit markings: Draft marks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Unit markings: Draft marks. 108.661 Section 108.661... AND EQUIPMENT Equipment Markings and Instructions § 108.661 Unit markings: Draft marks. (a) Each unit must have draft marks for each foot of immersion— (1) If the unit is a surface unit, on both the port...

  11. 46 CFR 108.661 - Unit markings: Draft marks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Unit markings: Draft marks. 108.661 Section 108.661... AND EQUIPMENT Equipment Markings and Instructions § 108.661 Unit markings: Draft marks. (a) Each unit must have draft marks for each foot of immersion— (1) If the unit is a surface unit, on both the port...

  12. Population pharmacokinetics of unbound hydrocortisone in critically ill neonates and infants with vasopressor-resistant hypotension

    PubMed Central

    Vezina, Heather E.; Ng, Chee M.; Vazquez, Delia M.; Barks, John D.; Bhatt-Mehta, Varsha

    2014-01-01

    Objective To determine the population pharmacokinetics of unbound hydrocortisone (HC) in critically ill neonates and infants receiving intravenous HC for treatment of vasopressor-resistant hypotension and to identify patient-specific sources of pharmacokinetic variability. Design Prospective observational cohort study. Setting Level 3 neonatal intensive care unit. Patients Sixty-two critically ill neonates and infants receiving intravenous HC as part of standard of care for the treatment of vasopressor-resistant hypotension: median gestational age 28 weeks (range, 23 to 41), median weight 1.2 kg (range, 0.5 to 4.4), 29 females. Interventions None. Measurements Unbound baseline cortisol and post-dose HC concentrations measured from blood samples being drawn for routine laboratory tests. Main Results A one compartment model best described the data. Allometric weight and postmenstrual age (PMA) were significant covariates on unbound HC clearance (CL) and volume of distribution (V). Final population estimates for CL, V, and baseline cortisol concentration were 20.2 L/h, 244 L, and 1.37 ng/mL, respectively. Using the median weight and PMA of our subjects (i.e. 1.2 kg and 28 weeks) in the final model, the typical unbound HC CL and V were 1.0 L/h and 4.2 L, respectively. The typical half-life for unbound HC was 2.9 hours. A sharp and continuous increase in unbound HC CL was observed at 35 weeks PMA. Conclusions We report the first pharmacokinetic data for unbound HC, the pharmacologically active moiety, in critically ill neonates and infants with vasopressor-resistant hypotension. Unbound HC CL increased with body weight and was faster in children with an older PMA. Unbound HC CL increased sharply at 35 weeks PMA and continued to mature thereafter. This study lays the groundwork for evaluating unbound HC exposure-response relationships and drawing definitive conclusions about the dosing of intravenous HC in critically-ill neonates and infants with vasopressor

  13. The effect of milrinone on induced hypotension in elderly patients during spinal surgery: a randomized controlled trial.

    PubMed

    Hwang, Wonjung; Kim, Eunsung

    2014-08-01

    Induced hypotension is widely used intraoperatively to reduce blood loss and to improve the surgical field during spinal surgery. To determine the effect of milrinone on induced hypotension during spinal surgery in elderly patients. Prospective randomized clinical trial. Forty patients, 60 to 70 years old, ASA I-II, who underwent elective lumbar fusion surgery. Intraoperative hemodynamics, blood loss, hourly urine output, and grade of surgical field. All patients were randomized to group M or N. The study drug was infused after perivertebral muscle retraction until complete interbody fusion. In group M, 50 μg/kg/min of milrinone was infused over 10 minutes as a loading dose followed by 0.6 μg/kg/min of milrinone as a continuous dose. In group N, an identical volume of normal saline was infused in the same fashion. This study was not funded by commercial or other sponsorship and the authors confirm no conflicts of interest, financial or otherwise. During infusion of the study drug, the systolic and mean blood pressures were maintained within adequate limits of induced hypotension in group M. Intraoperative blood loss was 445.0±226.5 mL in group M and 765.0±339.2 mL in group N (p=.001). Hourly urine output was 1.4±0.6 mL in group M and 0.8±0.2 mL in group N (p<.001). The grade of the surgical field was better in group M than in group N (p=.004). We conclude that milrinone is useful for induced hypotension in elderly patients during spinal surgery. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Prehospital management and fluid resuscitation in hypotensive trauma patients admitted to Karolinska University Hospital in Stockholm.

    PubMed

    Talving, Peep; Pålstedt, Joakim; Riddez, Louis

    2005-01-01

    Few previous studies have been conducted on the prehospital management of hypotensive trauma patients in Stockholm County. The aim of this study was to describe the prehospital management of hypotensive trauma patients admitted to the largest trauma center in Sweden, and to assess whether prehospital trauma life support (PHTLS) guidelines have been implemented regarding prehospital time intervals and fluid therapy. In addition, the effects of the age, type of injury, injury severity, prehospital time interval, blood pressure, and fluid therapy on outcome were investigated. This is a retrospective, descriptive study on consecutive, hypotensive trauma patients (systolic blood pressure < or = 90 mmHg on the scene of injury) admitted to Karolinska University Hospital in Stockholm, Sweden, during 2001-2003. The reported values are medians with interquartile ranges. Basic demographics, prehospital time intervals and interventions, injury severity scores (ISS), type and volumes of prehospital fluid resuscitation, and 30-day mortality were abstracted. The effects of the patient's age, gender, prehospital time interval, type of injury, injury severity, on-scene and emergency department blood pressure, and resuscitation fluid volumes on mortality were analyzed using the exact logistic regression model. In 102 (71 male) adult patients (age > or = 15 years) recruited, the median age was 35.5 years (range: 27-55 years) and 77 patients (75%) had suffered blunt injury. The predominant trauma mechanisms were falls between levels (24%) and motor vehicle crashes (22%) with an ISS of 28.5 (range: 16-50). The on-scene time interval was 19 minutes (range: 12-24 minutes). Fluid therapy was initiated at the scene of injury in the majority of patients (73%) regardless of the type of injury (77 blunt [75%] / 25 penetrating [25%]) or injury severity (ISS: 0-20; 21-40; 41-75). Age (odds ratio (OR) = 1.04), male gender (OR = 3.2), ISS 21-40 (OR = 13.6), and ISS >40 (OR = 43.6) were the

  15. Acute Radiation Hypotension in the Rabbit: a Model for the Human Radiation Shock Syndrome.

    NASA Astrophysics Data System (ADS)

    Makale, Milan Theodore

    This study has shown that total body irradiation (TBI) of immature (40 to 100 day old) rabbits leads to an acute fall in mean arterial pressure (MAP) 30 to 90 minutes after exposure, which takes no more than about three minutes, and often results in pressures which are less than 50% of the lowest pre-exposure MAP. This is termed acute cardiovascular collapse (ACC). ACC is often accompanied by ECG T-wave elevation, a sharp rise in ear temperature, labored breathing, pupillary constriction, bladder emptying, and loss of abdominal muscle tone. About 73% of 40 to 100 day rabbits exhibit ACC; the others and most older rabbits display gradual pressure reductions (deliberate hypotension) which may be profound, and which may be accompanied by the same changes associated with ACC. ACC and deliberate hypotension occurred in rabbits cannulated in the dorsal aorta, and in non-operated animals. The decline in MAP for all 40 to 100 day cannulated rabbits (deliberate and ACC responders) is 55.4%. The experiments described below only involved 40 to 100 day cannulated TBI rabbits. Heart region irradiation resulted in an average MAP decline of 29.1%, with 1/15 rabbits showing ACC. Heart shielding during TBI reduced the decline in MAP to 19%, with 1/10 rabbits experiencing ACC. These results imply that the heart region, which includes the heart, part of the lungs, neural receptors, roots of the systemic vessels, and the blood, is a sensitive target. Bilateral vagotomy reduced the decline in MAP to 24.9%, and abolished ACC. Atropine (6 mg/kg) reduced the frequency of ACC to 26%, and the decline in MAP to 41.4%. In 11/13 rabbits the voltage generated by left vagal transmission rose after TBI. The vagi appear to participate in radiation hypotension. Heart shielding together with bilateral vagotomy reduced the decline in MAP to only 9.9%, with no ACC responders. The mean right ventricular pressure (MRVP) rose after TBI in 8/10 rabbits. In animals which displayed either ACC or steep

  16. Extended Essay Marking on Screen: Is Examiner Marking Accuracy Influenced by Marking Mode?

    ERIC Educational Resources Information Center

    Johnson, Martin; Hopkin, Rebecca; Shiell, Hannah; Bell, John F.

    2012-01-01

    In the UK and elsewhere, large-scale educational assessment agencies are shifting the mode of school examination marking towards having examiners mark examination scripts on screen rather than on paper. This shift has prompted questions about whether the mode of marking might influence examiner marking accuracy, particularly in relation to…

  17. Effect of time to operation on mortality for hypotensive patients with gunshot wounds to the torso: The golden 10 minutes.

    PubMed

    Meizoso, Jonathan P; Ray, Juliet J; Karcutskie, Charles A; Allen, Casey J; Zakrison, Tanya L; Pust, Gerd D; Koru-Sengul, Tulay; Ginzburg, Enrique; Pizano, Louis R; Schulman, Carl I; Livingstone, Alan S; Proctor, Kenneth G; Namias, Nicholas

    2016-10-01

    Timely hemorrhage control is paramount in trauma; however, a critical time interval from emergency department arrival to operation for hypotensive gunshot wound (GSW) victims is not established. We hypothesize that delaying surgery for more than 10 minutes from arrival increases all-cause mortality in hypotensive patients with GSW. Data of adults (n = 309) with hypotension and GSW to the torso requiring immediate operation from January 2004 to September 2013 were retrospectively reviewed. Patients with resuscitative thoracotomies, traumatic brain injury, transfer from outside institutions, and operations occurring more than 1 hour after arrival were excluded. Survival analysis using multivariate Cox regression models was used for comparison. Hazard ratios (HRs) and 95% confidence intervals (CIs) are reported. Statistical significance was considered at p ≤ 0.05. The study population was aged 32 ± 12 years, 92% were male, Injury Severity Score was 24 ± 15, systolic blood pressure was 81 ± 29 mm Hg, Glasgow Coma Scale score was 13 ± 4. Overall mortality was 27%. Mean time to operation was 19 ± 13 minutes. After controlling for organ injury, patients who arrived to the operating room after 10 minutes had a higher likelihood of mortality compared with those who arrived in 10 minutes or less (HR, 1.89; 95% CI, 1.10-3.26; p = 0.02); this was also true in the severely hypotensive patients with systolic blood pressure of 70 mm Hg or less (HR, 2.67; 95% CI, 0.97-7.34; p = 0.05). The time associated with a 50% cumulative mortality was 16 minutes. Delay to the operating room of more than 10 minutes increases the risk of mortality by almost threefold in hypotensive patients with GSW. Protocols should be designed to shorten time in the emergency department. Further prospective observational studies are required to validate these findings. Therapeutic study, level IV.

  18. What is the definition of intraoperative hypotension in dogs? Results from a survey of diplomates of the ACVAA and ECVAA.

    PubMed

    Ruffato, Marco; Novello, Lorenzo; Clark, Louise

    2015-01-01

    Determine arterial blood pressure range that diplomates of the American College of Veterinary Anesthesia and Analgesia (ACVAA) and European College of Veterinary Anaesthesia and Analgesia (ECVAA) use to define intraoperative hypotension in dogs and identify the threshold values used for intervention. Survey of veterinary anesthesia specialists. Diplomates of the ACVAA and ECVAA. ACVAA and ECVAA diplomates (n = 313) were invited to participate in an Internet-based survey regarding anesthetized healthy dogs undergoing two types of procedures (diagnostic or surgical). There were 151 respondents to the survey; 70.2% were ACVAA diplomates and 29.8% were ECVAA diplomates. The majority of the respondents (70.9%) worked in academia while the others were in private practice (19.2%), or research, diagnostic or pharmaceutical fields (9.9%). Hypotension was defined (mean ± SD) by the respondents as systolic arterial blood pressure (SAP) <87 ± 8 mmHg for surgical cases and <87 ± 6 mmHg for diagnostic cases, or mean arterial pressure (MAP) <62 ± 4 mmHg for both types of cases. Arterial pressures reported to prompt treatment were SAP 85 ± 13 mmHg or MAP 61 ± 4 mmHg in surgical cases, and SAP 84 ± 11 mmHg or MAP 63 ± 8 mmHg in diagnostic cases. There was agreement between ACVAA and ECVAA diplomates on the definition of intraoperative hypotension in dogs during anesthesia. The blood pressures used to define hypotension were similar to the pressures that would prompt diplomates to start treatment. Readers could infer that diplomates define hypotension as a clinical condition that requires treatment at the time of diagnosis. © 2014 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

  19. Influence of intraoperative hypotension on leaks after sleeve gastrectomy.

    PubMed

    Nienhuijs, Simon W; Kaymak, Uzay; Korsten, Erik; Buise, Marc P

    2016-01-01

    Leak after a sleeve gastrectomy (SG) is a severe complication. Risk factors, such as regional ischemia, increased intraluminal pressure, technical failure of the stapling device, and surgeon error, have been reported. It was hypothesized that intraoperative hypotension is another risk factor for leak, similar to that reported for colorectal surgery. Tertiary teaching hospital in The Netherlands. Results of a 7-year cohort of primary SGs were reviewed in relation to multiple intraoperative blood pressure measurements. The thresholds for the mean pressure were 40 to 70 mm Hg and for the systolic pressure 70 to 100 mm Hg. Only continuous episodes of 15 and 20 minutes were included. Twenty-four leaks were identified in a cohort of 1041 primary SGs. Episodes of systolic blood pressure<100 mm Hg for 15 min (P = .027) and 20 minutes (P = .008) were significantly related to a staple line leak. An episode of mean blood pressure<70 mm Hg for 20 min was significantly related to leak (P = .014). Episodes with lower thresholds of pressure occurred less frequently and revealed no significant differences. Other identified risk factors were smoking (P = .019), fast-track recovery program (P = .006), use of a tri-stapler (P = .004), and duration of surgery (P = .000). In a multivariate analysis, only intraoperative systolic pressure<100 mm Hg for 20 minutes remained significant (odds ratio, 2.45; P = .012). Intraoperative hypotension may contribute independently to a leak after SG. Copyright © 2016 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

  20. Mechanism of action of hypotensive prostaglandins in patients with essential hypertension.

    PubMed

    Michibayashi, Tsutomu

    2002-06-01

    Despite extensive investigation, the biological mechanisms causing essential hypertension (EHT) remain unclear. To clarify the means by which hypotensive prostaglandins (Hypo-PGs, mainly PGE1 and PGE2) act in patients with EHT, the interaction between intravenously infused Hypo-PGs and pressor substances such as an adrenergic neurotransmitter, noradrenaline (NA) and angiotensin II (AII) was examined both in patients with EHT and in perfused isolated rabbit ear artery preparations. In patients with EHT, Hypo-PGs were shown to reduce the pressor responses to intravenously infused NA or AII, although no significant difference was found between the pressor responses to NA under basal conditions and the responses during intravenous infusion of Hypo-PGs. Animal studies were undertaken to investigate the inhibitory action of Hypo-PGs on the vasoconstrictive responses to electrical stimulation of the perivascular sympathetic nerves (VSNS) and to exogenous NA at pre- and postjunctional sites in blood vessel walls. The suppressive action of Hypo-PGs on the response to VSNS was shown to be more potent than that to their action on the response to exogenous NA. Thus, it was concluded that the hypotensive action of intravenously infused Hypo-PGs in patients with EHT may be more dependent on prejunctional sites than on the postjunctional sites in the walls of blood vessels.

  1. Neural mechanism of electroacupuncture's hypotensive effects

    PubMed Central

    Li, Peng; Longhurst, John C.

    2010-01-01

    EA at P 5–6 and S 36–37 using low current and low frequency may be able to reduce elevated blood pressure in a subset of patients (~70%) with mild to moderate hypertension. The effect is slow in onset but is long-lasting. Experimental studies have shown that EA inhibition of cardiovascular sympathetic neurons that have been activated through visceral reflex stimulation is through activation of neurons in the arcuate nucleus of the hypothalamus, vlPAG in the midbrain and NRP in the medulla, which, in turn, inhibit the activity of premotor sympathetic neurons in the rVLM. The arcuate also provides direct projections to the rVLM that contain endorphins. Glutamate, acetylcholine, opioids, GABA, nociceptin, serotonin and endocannabinoids all appear to participate in the EA hypotensive response although their importance varies between nuclei. Thus, a number of mechanisms underlying the long-lasting effect of EA on cardiovascular function have been identified but clearly further investigation is warranted. PMID:20444652

  2. Bilateral blindness secondary to optic nerve ischemia from severe amlodipine overdose: a case report.

    PubMed

    Kao, Raymond; Landry, Yves; Chick, Genevieve; Leung, Andrew

    2017-08-03

    Calcium channel blockers are commonly prescribed medications; calcium channel blocker overdose is becoming increasingly prevalent. The typical presentation of a calcium channel blocker overdose is hypotension and decreased level of consciousness. We describe a case of a calcium channel blocker overdose that led to bilateral cortical blindness, a presentation that has not previously been reported. A 49-year-old white woman with known bilateral early optic atrophy presented to our hospital with hypotension and obtundation following a known ingestion of 150 mg of amlodipine. She was transferred to our intensive care unit where she was intubated, mechanically ventilated, and required maximal vasopressor support (norepinephrine 40 mcg/minute, epinephrine 40 mcg/minute, and vasopressin 2.4 units/hour) along with intravenously administered crystalloid boluses. Despite these measures, she continued to deteriorate with persistent hypotension and tachycardia, as well as anuria. Intralipid emulsion therapy was subsequently administered to which no initial response was observed. A chest X-ray revealed diffuse pulmonary edema; intravenous diuresis as well as continuous renal replacement therapy was initiated. Following the initiation of continuous renal replacement therapy, her oxygen requirements as well as urine output began to improve, and 3 days later she was liberated from mechanical ventilation. Following extubation, she complained of new onset visual impairment, specifically seeing only red-green colors, but no objects. An ophthalmologic examination revealed that this was due to bilateral optic atrophy from prolonged hypotension during the first 24 hours after the overdose. Persistent hypotension in the setting of a calcium channel blocker overdose can lead to worsening optic atrophy resulting in bilateral cortical blindness.

  3. Dialysate bicarbonate variation in maintenance hemodiafiltration patients: Impact on serum bicarbonate, intradialytic hypotension and interdialytic weight gain.

    PubMed

    Viegas, Márcio; Cândido, Cristina; Felgueiras, Joana; Clemente, José; Barros, Sara; Farbota, Rostislav; Vera, Filipa; Matos, Antero; Sousa, Francisco

    2017-07-01

    The dialysate bicarbonate (DB) influences the acid-base balance in dialysis patients. Very low and high serum bicarbonate (SB) have been related with a higher mortality. Acid-base balance also has been associated with hemodynamic effects in these patients. The trial aim was to compare the effect of DB concentration variation on SB levels in maintenance hemodiafiltration (HDF) patients and the effect on intradialytic hypotension and interdialytic weight gain. A prospective study, with 9 months of follow-up, involving 93 patients, divided in two groups: group 1 and group 2 with a DB of 34 mmol/L and 30 mmol/L, respectively, with monitoring of pre and post HDF SB, intradialytic hypotension, and interdialytic weight gain. Pre dialysis SB was higher in group 1: median concentration of 22.7 mmol/L vs. 21.1 mmol/L (P < 0.001). Post dialysis SB levels were higher in group 1: median concentration of 28.0 mmol/L vs. 25.3 mmol/L (P < 0.001). Post dialysis SB in alkalotic range was only detected in group 1 (51.2% of the patients). No significant differences were detected in intradialytic hypotension rate [28.0 vs. 27.4 episodes per 1000 sessions in group 1 and 2, respectively, (P = 0.906)] or in average interdialytic weight gain [2.9% vs. 3.0% in group 1 and 2, respectively, (P = 0.710)]. DB of 30 mmol/L appears to be associated with SB levels closer to physiological levels than 34 mmol/L. The bicarbonate dialysate, in the tested concentrations, did not appear to have a significant impact on intradialytic hypotension and interdialytic weight gain in maintenance HDF patients. © 2016 International Society for Hemodialysis.

  4. Meta-analysis of the safety and efficacy of droxidopa for neurogenic orthostatic hypotension.

    PubMed

    Elgebaly, Ahmed; Abdelazeim, Bassant; Mattar, Omar; Gadelkarim, Mohamed; Salah, Rehab; Negida, Ahmed

    2016-06-01

    Droxidopa has been approved for the treatment of neurogenic orthostatic hypotension (NOH) under the US Food and Drug Administration accelerated approval program, which warrants confirmatory evidence on long-term efficacy of droxidopa. Hereby, we synthesize evidence from published randomized controlled trials (RCTs) about the safety and efficacy of droxidopa for patients with neurogenic orthostatic hypotension. A computer literature search of PubMed, Scopus, Web of Science, and Cochrane Central was conducted using relevant keywords. Records were screened for eligible studies and data were extracted and synthesized using Review Manager version 5.3 for Windows. Subgroup analysis and sensitivity analysis were conducted to investigate long-term durability of droxidopa against placebo. Four RCTs with a total of 485 patients (droxidopa, n = 246; placebo, n = 239) were eligible for the final analysis. The mean difference (MD) of change in the main outcomes from baseline to endpoint favored droxidopa than placebo [Orthostatic Hypotension Questionnaire (OHQ) MD -0.61, P = 0.004; dizziness/lightheadedness score MD -0.83, P = 0.008; and standing systolic blood pressure (SBP) MD 4.09, P = 0.03]. The efficacy of droxidopa decreased gradually after 2 weeks, and its statistical significance was lost after 8 weeks (OHQ score MD -0.18, P = 0.61; dizziness/lightheadedness score MD -0.71, P = 0.11; and standing SBP MD 2.96, P = 0.29). None of the adverse events were significantly higher in the case of droxidopa compared to placebo. Droxidopa is a safe and effective drug for the short-term management of NOH symptoms. However, current evidence is insufficient to confirm the efficacy of droxidopa for long-term use. Therefore, further studies with increased sample size are needed.

  5. A New Orally Active, Aminothiol Radioprotector-Free of Nausea and Hypotension Side Effects at Its Highest Radioprotective Doses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Soref, Cheryl M.; Hacker, Timothy A.; Fahl, William E., E-mail: fahl@oncology.wisc.edu

    Purpose: A new aminothiol, PrC-210, was tested for orally conferred radioprotection (rats, mice; 9.0 Gy whole-body, which was otherwise lethal to 100% of the animals) and presence of the debilitating side effects (nausea/vomiting, hypotension/fainting) that restrict use of the current aminothiol, amifostine (Ethyol, WR-2721). Methods and Materials: PrC-210 in water was administered to rats and mice at times before irradiation, and percent-survival was recorded for 60 days. Subcutaneous (SC) amifostine (positive control) or SC PrC-210 was administered to ferrets (Mustela putorius furo) and retching/emesis responses were recorded. Intraperitoneal amifostine (positive control) or PrC-210 was administered to arterial cannulated rats tomore » score drug-induced hypotension. Results: Oral PrC-210 conferred 100% survival in rat and mouse models against an otherwise 100% lethal whole-body radiation dose (9.0 Gy). Oral PrC-210, administered by gavage 30-90 min before irradiation, conferred a broad window of radioprotection. The comparison of PrC-210 and amifostine side effects was striking because there was no retching or emesis in 10 ferrets treated with PrC-210 and no induced hypotension in arterial cannulated rats treated with PrC-210. The tested PrC-210 doses were the ferret and rat equivalent doses of the 0.5 maximum tolerated dose (MTD) PrC-210 dose in mice. The human equivalent of this mouse 0.5 MTD PrC-210 dose would likely be the highest PrC-210 dose used in humans. By comparison, the mouse 0.5 MTD amifostine dose, 400 {mu}g/g body weight (equivalent to the human amifostine dose of 910 mg/m{sup 2}), when tested at equivalent ferret and rat doses in the above models produced 100% retching/vomiting in ferrets and 100% incidence of significant, progressive hypotension in rats. Conclusions: The PrC-210 aminothiol, with no detectable nausea/vomiting or hypotension side effects in these preclinical models, is a logical candidate for human drug development to use in

  6. Post-Exercise Hypotension and Its Mechanisms Differ after Morning and Evening Exercise: A Randomized Crossover Study

    PubMed Central

    da Silva Junior, Natan D.; Tinucci, Tais; Casarini, Dulce E.; Cipolla-Neto, José

    2015-01-01

    Post-exercise hypotension (PEH), calculated by the difference between post and pre-exercise values, it is greater after exercise performed in the evening than the morning. However, the hypotensive effect of morning exercise may be masked by the morning circadian increase in blood pressure. This study investigated PEH and its hemodynamic and autonomic mechanisms after sessions of aerobic exercise performed in the morning and evening, controlling for responses observed after control sessions performed at the same times of day. Sixteen pre-hypertensive men underwent four sessions (random order): two conducted in the morning (7:30am) and two in the evening (5pm). At each time of day, subjects underwent an exercise (cycling, 45 min, 50%VO2peak) and a control (sitting rest) session. Measurements were taken pre- and post-interventions in all the sessions. The net effects of exercise were calculated for each time of day by [(post-pre exercise)-(post-pre control)] and were compared by paired t-test (P<0.05). Exercise hypotensive net effects (e.g., decreasing systolic, diastolic and mean blood pressure) occurred at both times of day, but systolic blood pressure reductions were greater after morning exercise (-7±3 vs. -3±4 mmHg, P<0.05). Exercise decreased cardiac output only in the morning (-460±771 ml/min, P<0.05), while it decreased stroke volume similarly at both times of day and increased heart rate less in the morning than in the evening (+7±5 vs. +10±5 bpm, P<0.05). Only evening exercise increased sympathovagal balance (+1.5±1.6, P<0.05) and calf blood flow responses to reactive hyperemia (+120±179 vs. -70±188 U, P<0.05). In conclusion, PEH occurs after exercise conducted at both times of day, but the systolic hypotensive effect is greater after morning exercise when circadian variations are considered. This greater effect is accompanied by a reduction of cardiac output due to a smaller increase in heart rate and cardiac sympathovagal balance. PMID:26186444

  7. The efficacy and hemodynamic response to Dexmedetomidine as a hypotensive agent in posterior fixation surgery following traumatic spine injury

    PubMed Central

    Jamaliya, Ramila H; Chinnachamy, Rajesh; Maliwad, Jyotsna; Deshmukh, Varun P; Shah, Bharat J; Chadha, Indu A

    2014-01-01

    Aim: This study was designed to evaluate the efficacy of dexmedetomidine (DEX) as a hypotensive agent in comparison to nitroglycerin (NTG) in posterior fixation surgery for traumatic spine injury. Materials and Methods: Forty patients ASA I or II aged 18-65 years scheduled for posterior fixation surgery were randomly assigned to receive either DEX 1 μg/kg over 10 min before induction of anesthesia followed by 0.2-0.7 μg/kg/h infusion during maintenance in DEX group or NTG 3-5 μg/kg/min infusion after induction of anesthesia in NTG group to maintain mean arterial blood pressure (MAP) between 65 and 70 mmHg. The two groups were compared for achievement of target MAP, intraoperative blood loss, and reversibility of hypotensive state. Student's t-test was used for continuous variables and chi-square test for categorical variables. P-value < 0.05 was considered significant. Results: Patients in DEX group achieved the target MAP with better heart rate (HR) control, as compared to NTG group during the period of observation. The blood loss was significantly lesser in the DEX group (422.11 ± 149.34 ml) than the NTG group (564.51 ± 160.88 ml), P = 0.01. The time to hypotension reversal in NTG group (5.63 ± 1.93 min) was lesser compared to DEX group (9.15 ± 2.16 min), P = 0.65. Conclusion: DEX is an effective and safe agent in achieving controlled hypotension in adults undergoing posterior fixation spine surgery. PMID:24803758

  8. Pre-existing arterial stiffness can predict hypotension during induction of anaesthesia in the elderly.

    PubMed

    Alecu, C; Cuignet-Royer, E; Mertes, P M; Salvi, P; Vespignani, H; Lambert, M; Bouaziz, H; Benetos, A

    2010-11-01

    The aim of the present study was to establish whether elevated carotid-femoral pulse wave velocity (c-fPWV), an indicator of aortic stiffness, assessed before surgery, is correlated with variations in arterial pressure (AP) during induction of anaesthesia in elderly patients undergoing non-cardiovascular surgery. c-fPWV was measured with the PulsePen(®) device during pre-surgical anaesthetic evaluation. Monitoring included electrocardiography, pulse oximetry, non-invasive AP, heart rate, bispectral index (BIS), and oxygen concentration during induction of anaesthesia with propofol and remifentanil. Anaesthesia was induced so as to maintain BIS values between 40 and 50. Forty-five patients, aged [mean (sd)] 71.1 (5.8) yr, were studied. The mean value of c-fPWV was 12.1 (3.9) m s⁻¹. There was no correlation between hypotension during anaesthesia induction and total dosage or rate of administration of propofol or remifentanil. In univariate analysis, only age and PWV significantly correlated with the decreases in AP, and the association between c-fPWV and a decrease in AP was also seen in multivariate analysis (r = 0.36, P< 0.05). Patients classified as having 'high stiffness' (c-fPWV ≥ 12.9 m s⁻¹) had 25% further decrease in systolic AP during anaesthesia induction than those with lower PWV [75.2 (5.7) vs 60.2 (4.2) mm Hg, P < 0.05]. Increased aortic stiffness, as assessed by PWV measured during preoperative anaesthetic evaluation, is associated with more pronounced hypotension during induction of anaesthesia. Measurement of aortic stiffness in the elderly may thus represent a valid indicator of the risk of hypotension during anaesthesia induction.

  9. Role of prostaglandin/cAMP pathway in the diuretic and hypotensive effects of purified fraction of Maytenus ilicifolia Mart ex Reissek (Celastraceae).

    PubMed

    Leme, Thiago dos Santos Vilhena; Prando, Thiago Bruno Lima; Gasparotto, Francielly Mourão; de Souza, Priscila; Crestani, Sandra; de Souza, Lauro Mera; Cipriani, Thales Ricardo; Lourenço, Emerson Luiz Botelho; Gasparotto, Arquimedes

    2013-10-28

    Although Maytenus ilicifolia is used in Brazilian folk medicine as a diuretic drug, no study has been conducted to this date in order to evaluate this ethnopharmacological statement. So, the aim of this study was to evaluate possible mechanisms involved in acute diuretic activity of the ethanolic supernatant of the infusion (SEI) obtained from Maytenus ilicifolia and to assess its relationship with a hypotensive activity by a bioassay-guided fractionation using normotensive Wistar rats. The preparation obtained from the infusion (SEI) and their respective fractions (Fr·H2O and Fr·EtOAc) were orally administered in a single dose to rats. The urine excretion rate, pH, density, conductivity and content of Na(+), K(+), Cl(-) and HCO3(-) were measured in the urine of saline-loaded animals. Samples of the concentration of electrolytes, urea, creatinine, aldosterone, vasopressin and angiotensin converting enzyme (ACE) activity were evaluated in collected serum. The hypotensive activity and the involvement of nitric oxide, bradykinin and prostaglandin/cAMP pathway in the hypotensive and diuretic effects were also determined. Water and Na(+) excretion rate were significantly increased by Fr·EtOAc and the arterial pressure was significantly reduced, while the urinary excretion of potassium and chloride were reduced. Pre-treatment with indomethacin or DDA (2',5'-dideoxyadenosine) significantly reduced the hypotensive and diuretic activity observed. All other parameters evaluated were not affected by any treatment. The present study reveals that Fr·EtOAc obtained from Maytenus ilicifolia may present compounds responsible for diuretic and hypotensive activities, and this effect, could involve the prostaglandin/cAMP pathway. © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Spontaneous intracranial hypotension.

    PubMed

    Gordon, Neil

    2009-12-01

    Since the introduction of magnetic resonance imaging (MRI), spontaneous intracranial hypotension has been diagnosed much more frequently. The aim of this review is to discuss the symptoms and signs of the condition, in particular the characteristics of the associated headache, with sudden onset after sitting or standing, so that it can be included under the rubric of 'thunderclap headache'. This type of headache, like post lumbar puncture headaches, may be caused by cerebral vasodilatation and exacerbated by lowered pressure of the cerebrospinal fluid (CSF). Other symptoms include neck stiffness, nausea, vomiting, vertigo, tinnitus, deafness, and cognitive abnormalities. The clinical picture can sometimes mimic frontotemporal dementia, and the behaviour of some patients can sometimes be described as hypoactive-hypoalert, with somnolence, impaired attention, and stereotyped motor activity. Sagging of the brain, caused by leakeage of the CSF, can cause lesions in the brainstem with stupor, gaze palsies, and cranial nerve palsies. The condition can be a risk factor for cerebral venous thrombosis because of slowing of the blood flow and distortion of the blood vessels. The clinical picture may well suggest the diagnosis, but the headache may possibly indicate a subarachnoid haemorrhage. However, MRI will help to confirm the diagnosis and to localize the site of the CSF leak. MRI myelograms are of particular value, but if they are equivocal a computed tomography myelogram should be performed. The leakage of CSF is due to a tear in the dura, most frequently where the spinal roots leave the subarachnoid space. If this does not heal with bedrest, an epidural blood patch or a percutaneous injection of fibrin glue may be needed. More information is required on long-term follow-up.

  11. Transient adrenocortical insufficiency of prematurity and systemic hypotension in very low birthweight infants

    PubMed Central

    Ng, P; Lee, C; Lam, C; Ma, K; Fok, T; Chan, I; Wong, E

    2004-01-01

    Objectives: A proportion of preterm, very low birthweight (VLBW, < 1500 g) infants may show inadequate adrenal response to stress in the immediate postnatal period. The human corticotrophin releasing hormone (hCRH) stimulation test was used to: (a) determine the relation between pituitary-adrenal response and systemic blood pressure in these infants; (b) characterise the endocrinological features of transient adrenocortical insufficiency of prematurity (TAP). Study design: A total of 226 hCRH tests were performed on 137 VLBW infants on day 7 and 14 of life in a tertiary neonatal centre. Results: Basal, peak, and incremental rise in serum cortisol (ΔCort0–30) on day 7 were associated significantly with the lowest systolic, mean, and diastolic blood pressures recorded during the first two weeks of life (r > 0.25, p < 0.005). These cortisol concentrations also correlated significantly but negatively with the maximum and total cumulative dose of dopamine (r > -0.22, p < 0.02), dobutamine (r > -0.18, p < 0.04), and adrenaline (r > -0.26, p < 0.004), total volume of crystalloid (r > -0.22, p < 0.02), and duration of inotrope treatment (r > -0.25, p < 0.006). Multivariate regression analysis of significant factors showed that the lowest systolic, mean, and diastolic blood pressures remained independently associated with serum cortisol (basal, peak, and ΔCort0–30) on day 7. Hypotensive infants requiring inotropes (group 2) were significantly less mature and more sick than infants with normal blood pressure (group 1). The areas under the ACTH response curves were significantly greater in group 2 than in group 1, on both day 7 (p = 0.004) and day 14 (p = 0.004). In contrast, the area under the cortisol response curve was significantly greater in group 1 than in group 2 on day 7 (p = 0.001), but there was no significant difference between the two groups on day 14. In addition, serum cortisol at the 50th centile in hypotensive infants had high specificity and positive

  12. Comparative efficacy of yohimbine against pyridostigmine for the treatment of orthostatic hypotension in autonomic failure.

    PubMed

    Shibao, Cyndya; Okamoto, Luis E; Gamboa, Alfredo; Yu, Chang; Diedrich, Andre'; Raj, Satish R; Robertson, David; Biaggioni, Italo

    2010-11-01

    Orthostatic hypotension affects patients with autonomic failure producing considerable disability because of presyncopal symptoms. Severely affected patients may have residual sympathetic tone that can be engaged to increase blood pressure (BP) with the α-2 adrenergic antagonist yohimbine. This medication activates sympathetic outflow centrally and unrestrains norepinephrine release from noradrenergic neurons. Alternatively, the acetylcholinesterase inhibitor, pyridostigmine, can increase sympathetic tone by improving ganglionic cholinergic neurotransmission. Our purpose was to compare these complementary approaches and to explore whether the combination would lead to synergistic increases in BP. We compared the effects of 60 mg of pyridostigmine and 5.4 mg of yohimbine in a single-blind, randomized, placebo-controlled, crossover fashion. In a subset of patients we tested the combination of pyridostigmine and yohimbine. Our primary outcome was the change in standing diastolic BP 60 minutes after drug administration from baseline. We studied a total of 31 patients with severe autonomic failure. Yohimbine significantly improved standing diastolic BP as compared with placebo (11±3 mm Hg [95% CI: 6 to 16 mm Hg]; P<0.001). On the contrary, pyridostigmine did not increase the standing diastolic BP (0.6±3 mm Hg [95% CI: -5 to 5 mm Hg]; P=0.823). Only yohimbine showed a significant improvement in presyncopal symptoms. Sixteen patients received the combination of pyridostigmine and yohimbine, but no evidence of synergistic pressor effect was found. Engaging residual sympathetic tone with yohimbine is a more effective approach to improve orthostatic hypotension as compared with pyridostigmine in patients with severe orthostatic hypotension.

  13. COMPARATIVE EFFICACY OF YOHIMBINE AGAINST PYRIDOSTIGMINE FOR THE TREATMENT OF ORTHOSTATIC HYPOTENSION IN AUTONOMIC FAILURE

    PubMed Central

    Shibao, Cyndya; Okamoto, Luis E.; Gamboa, Alfredo; Yu, Chang; Diedrich, Andre'; Raj, Satish R.; Robertson, David; Biaggioni, Italo

    2010-01-01

    Orthostatic hypotension affects patients with autonomic failure producing considerable disability because of pre-syncopal symptoms. Severely affected patients may have residual sympathetic tone that can be engaged to increase blood pressure with the alpha-2 adrenergic antagonist yohimbine. This medication activates sympathetic outflow centrally and unrestrains norepinephrine release from noradrenergic neurons. Alternatively, the acetylcholinesterase inhibitor, pyridostigmine, can increase sympathetic tone by improving ganglionic cholinergic neurotransmission. Our purpose was to compare these complementary approaches and test the hypothesis that the combination would lead to synergistic increases in blood pressure. We compared the effects of pyridostigmine 60 mg and yohimbine 5.4 mg in a single-blind, randomized, placebo-controlled, crossover fashion. In a subset of patients we tested the combination of pyridostigmine and yohimbine. Our primary outcome was the change in standing diastolic blood pressure 60 minutes after drug administration from baseline. We studied a total of 31 patients with confirmed severe autonomic failure. Yohimbine significantly improved standing diastolic blood pressure as compared to placebo (11±3 mm Hg 95%CI: 6 to 16, P <0.001). On the contrary, Pyridostigmine did not increase the standing diastolic blood pressure (0.6±3 mm Hg 95%CI: −5 to 5, P =0.823). Only yohimbine showed a significant improvement in presyncopal symptoms. Sixteen patients received the combination of pyridostigmine and yohimbine, but no evidence of synergistic pressor effect was found. Engaging residual sympathetic tone with yohimbine is a more effective approach to improve orthostatic hypotension as compared to pyridostigmine in patients with severe orthostatic hypotension. PMID:20837887

  14. Evaluation of the advantageous anesthetic properties of dexmedetomidine used as hypotensive agent compared with nitroglycerin in orthognathic surgery.

    PubMed

    Rummasak, Duangdee; Apipan, Benjamas

    2014-12-01

    To evaluate the advantageous anesthetic properties, such as the decrease of intraoperative analgesic requirement, time to extubation and recovery, and early postoperative pain, of dexmedetomidine used as hypotensive agent compared with nitroglycerin in orthognathic surgery. The authors implemented a prospective, single-blinded, randomized clinical trial. The sample was composed of healthy patients who were admitted for bimaxillary osteotomies and were assigned to 1 of 2 groups by a computer-generated random number and blinded to the group. Dexmedetomidine or nitroglycerin was used as the hypotensive drug for each group. All patients underwent hypotensive anesthesia and surgery according to standard protocol. Intraoperative amount of fentanyl, time to eye opening, time to follow basic verbal commands, time to extubation, early postoperative pain scores, and analgesics were recorded. Compared means were analyzed using the unpaired Student t test. A 2-sided statistical test was used. A P value less than .05 was considered significant. The sample was composed of 40 participants. The intraoperative fentanyl requirement was significantly lower in the dexmedetomidine group than in the nitroglycerin group (168.75±56.29 and 222.50±96.12 μg, respectively; P=.037). Times to eye opening and following commands were considerably longer in the dexmedetomidine group, but the time to extubation showed no meaningful difference. Early postoperative pain after 30 and 60 minutes and the requirement for meperidine were not meaningfully different between the 2 groups. Dexmedetomidine, used as a hypotensive drug, has anesthetic benefits compared with nitroglycerin. Dexmedetomidine decreases the intraoperative fentanyl requirement and does not meaningfully change the time to extubation, early postoperative pain, and analgesic drug requirement. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  15. Impact of hypotension after return of spontaneous circulation on survival in patients of out-of-hospital cardiac arrest.

    PubMed

    Chiu, Yu Koon; Lui, Chun Tat; Tsui, Kwok Leung

    2018-01-01

    To investigate the relationship between hypotension in the first 3h after return of spontaneous circulation (ROSC) in patients with out-of-hospital cardiac arrest. This retrospective cohort study occurred at two regional hospitals and included adult OHCA patients who experienced ROSC from July 1, 2014 to December 31, 2015. Hemodynamic and inotrope administration data were retrieved for 3h after ROSC. We calculated the hypotensive exposure index (HEI) as the surrogate marker of the exposure of hypotension. The area under the ROC curve and multivariate logistic regression models were performed to analyze the effect of HEI on survival. Mean arterial pressure (MAP) was explored in the surviving and non-surviving patient groups using repeated measures MANCOVA, adjusted for the use of inotropes and down time. A total of 289 patients were included in the study, and 29 survived. The median 1-hour HEI and 3-hour HEI were significantly lower in the survival group (p<0.001). The area under the ROC curve for 3-hour HEI was 0.861. The repeated measures MANCOVA indicated that an interaction existed between post-ROSC time and downtime [F(5,197)=2.31, p=0.046]. No significant change in the MAP was observed in the 3h after ROSC, except in the group with a prolonged down time. According to the tests examining the effects of the use of inotropes on the survival outcomes of the different subjects, the MAP was significantly higher in the surviving group [F(1,201)=4.11; p=0.044; ηp2=0.020]. Among the patients who experienced ROSC after OHCA, post-ROSC hypotension was an independent predictor of survival. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Role of the median preoptic nucleus in the chronic hypotensive effect of losartan in sodium-replete normal rats.

    PubMed

    Ployngam, Trasida; Katz, Stephen S; Collister, John P

    2010-01-01

    1. We have shown previously that the chronic hypotensive effect of the angiotensin II AT1 receptor antagonist losartan is mediated, in part, by the subfornical organ (SFO). However, the neural pathway(s) mediating this central effect of losartan downstream from the SFO has not been completely elucidated. 2. The present study was designed to test the hypothesis that the median preoptic nucleus (MnPO) is a crucial part of the neural pathway necessary for the chronic hypotensive effect of losartan. To test this hypothesis, male Sprague-Dawley rats were subjected to either Sham or electrolytic lesion of the MnPO (MnPOx). Rats were instrumented with radiotelemetric transducers and aortic flow probes for the continuous measurement of mean arterial pressure (MAP) and heart rate and cardiac output (CO), respectively. Total peripheral resistance (TPR) was calculated as MAP/CO. After 3 days of baseline measurements, rats were infused intraperitoneally with losartan (10 mg/kg per day) via an osmotic minipump at a rate of 5 microL/min. 3. The data revealed that, by Day 9 of losartan treatment, MAP had decreased 34 +/- 2 mmHg in MnPOx rats (n = 9), whereas the MAP of Sham-lesioned rats (n = 8) had only decreased 24 +/- 3 mmHg. These findings were accompanied by a greater decrease in TPR in MnPOx compared with Sham rats (-0.464 vs-0.237 mmHg/mL per min, respectively), whereas CO remained unchanged throughout the study protocol. 4. These results do not support the hypothesis that an intact MnPO is necessary to mediate the full chronic hypotensive effect of losartan in normal rats. Instead, they appear to suggest that the MnPO may play an important role in buffering the profound hypotension induced by losartan.

  17. Cationic solid lipid nanoparticles enhance ocular hypotensive effect of melatonin in rabbit.

    PubMed

    Leonardi, Antonio; Bucolo, Claudio; Drago, Filippo; Salomone, Salvatore; Pignatello, Rosario

    2015-01-15

    The study was aimed at evaluating whether the ocular hypotensive effect of melatonin (MEL) was enhanced by its encapsulation in cationic solid lipid nanoparticles (cSLN), as well as at determining the tolerability of these formulations on the ocular surface. MEL was loaded in cSLN that had already been shown to be suitable for ophthalmic use. The formulations were prepared using Softisan(®) 100 as the main lipid matrix, with the presence of either stearic (SA) or palmitic acid (PA) as lipid modifiers. A fixed positive charge was provided by the addition of a cationic lipid (didecyldimethylammonium bromide). The ocular hypotensive effect was evaluated by measuring the intraocular pressure (IOP) during 24h in albino rabbits. MEL elicited a significant (p<0.01) IOP reduction in rabbit eye. All the formulations tested in vivo demonstrated a good tolerability. The nanocarrier containing SA was the most effective in terms of IOP reduction (maximum IOP reduction: -7 mmHg), and its effect lasted approximately 24h. The experimental data indicate that the new formulations based on cSLN loaded with MEL represent a potent anti-glaucoma treatment with a safe profile, warranting further clinical evaluation of the proposed nanotechnological strategy. Copyright © 2014. Published by Elsevier B.V.

  18. Profound Obstructive Hypotension From Prone Positioning Documented by Transesophageal Echocardiography in a Patient With Scoliosis: A Case Report.

    PubMed

    Abcejo, Arnoley S; Diaz Soto, Juan; Castoro, Courtney; Armour, Sarah; Long, Timothy R

    2017-08-01

    In a healthy 12-year-old female with scoliosis, prone positioning resulted in pressor-refractory cardiovascular collapse. Resumption of supine position immediately improved hemodynamics. Intraoperative transesophageal echocardiography (TEE) revealed a collapsed left atrium and biventricular failure. Repeat prone positioning resulted in a recurrence of hypotension. However, hemodynamic stabilization was restored and maintained by repositioning chest pads caudally. The patient successfully underwent a 6-hour scoliosis repair without perioperative morbidity. With this case, we aim to: (1) reintroduce awareness of this mechanical obstructive cause of reversible hypotension; (2) highlight the use of intraoperative TEE during prone hemodynamic collapse; and (3) suggest an alternative prone positioning technique if chest compression results in hemodynamic instability.

  19. Injection speed of spinal anaesthesia for Caesarean delivery in Asian women and the incidence of hypotension: A randomised controlled trial.

    PubMed

    Chiang, Chun Fai; Hasan, M Shahnaz; Tham, Sin Wan; Sundaraj, Sebastian; Faris, Ahmad; Ganason, Nagappan

    2017-06-01

    The purpose of this investigation was to determine if a slower speed of spinal anaesthesia injection would reduce the incidence of hypotension. Randomised controlled trial. Tertiary level hospital in Malaysia. 77 patients undergoing elective Caesarean delivery. Differing speeds of spinal injection. Systolic blood pressure was assessed every minute for the first 10min and incidence of hypotension (reduction in blood pressure of >30% of baseline) was recorded. The use of vasopressor and occurrence of nausea/vomiting were also recorded. 36 patients in SLOW group and 41 patients in FAST group were recruited into the study. There was no significant difference in blood pressure drop of >30% (p=0.497) between the two groups. There was no difference in the amount of vasopressor used and incidence of nausea/vomiting in both groups. In our study population, there was no difference in incidence of hypotension and nausea/vomiting when spinal injection time is prolonged beyond 15s to 60s. ClinicalTrials.govNCT02275897. Registered on 15 October 2014. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Comparison of two different approaches to hypotension following spinal anaesthesia for Caesarean delivery: effects on neonatal and maternal wellbeing.

    PubMed

    Zasa, Michele; Conci, Eleonora; Marchignoli, Alessandro; Pini, Rita; Passeri, Lorenzo; Fanelli, Guido; Cornini, Andrea

    2015-04-27

    Maternal hypotension during spinal anaesthesia for Caesarean delivery is a common event, with potential detrimental consequences. We led a prospective, randomized study to compare the effects of two strategies on neonatal and maternal wellbeing. Parturients scheduled for elective Caesarean section in spinal anaesthesia were preoperatively studied with a supine stress test. Those with a positive test were enrolled in the study and received a solution of 0.5% hyperbaric bupivacaine 12.5 mg and 0.02% morphine 200 µg intrathecally. Patients received a 37.5 mg/h preventive intravenous (IV) infusion of ephedrine (Pharmacologic Group), or a 15° left lateral tilt (Non-Pharmacologic Group). In Pharmacolgic Group hypotension was treated for 20% drops in systolic blood pressure; in Non-Pharmacolgic Group only severe hypotension - defined as a 40% drop in systolic blood pressure - was treated. Thirty-six patients were studied. Study groups were statistically similar in terms of demographic variables and intraoperative times. No statistical differences were found in terms of umbilical arterial blood base excess [-1.4 (-3.7 to -0.3) mEq/l Pharmacologic Group vs. -1.7 (-2.7 to -1.0) mEq/l Non-Pharmacologic Group; p=0.815] and other umbilical blood gas values. Apgar scores were statistically similar between study groups. Treatment for hypotension was required by 13 (72.2%) patients in Pharmacologic Group and 9 (50%) patients in Non-Pharmacologic Group (p=0.171). No differences were found at the analysis of serial changes in vital signs. Both studied strategies guaranteed a comparable safe outcome in terms of maternal and neonatal wellbeing. (www.actabiomedica.it).

  1. Fludrocortisone does not prevent orthostatic hypotension in astronauts after spaceflight.

    PubMed

    Shi, Shang-Jin; South, Donna A; Meck, Janice V

    2004-03-01

    During stand/tilt tests after spaceflight, 20% of astronauts experience orthostatic hypotension and presyncope. Spaceflight-induced hypovolemia is a contributing factor. Fludrocortisone, a synthetic mineralocorticoid, has been shown to increase plasma volume and orthostatic tolerance in Earth-bound patients. The efficacy of fludrocortisone as a treatment for postflight hypovolemia and orthostatic hypotension in astronauts has not been studied. Our purpose was to test the hypothesis that astronauts who ingest fludrocortisone prior to landing would have less loss of plasma volume and greater orthostatic tolerance than astronauts who do not ingest fludrocortisone. There were 25 male astronauts who were randomized into 2 groups: placebo (n = 18) and fludrocortisone (n = 7), and participated in stand tests 10 d before launch and 2-4 h after landing. Subjects took either 0.3 mg fludrocortisone or placebo orally 7 h prior to landing. Supine plasma and red cell volumes, supine and standing HR, arterial pressure, aortic outflow, and plasma norepinephrine and epinephrine were measured. On landing day, 2 of 18 in the placebo group and 1 of 7 in the fludrocortisone group became presyncopal (chi2 = 0.015, p = 0.90). Plasma volumes were significantly decreased after flight in the placebo group, but not in the fludrocortisone group. During postflight stand tests, standing plasma norepinephrine was significantly less in the fludrocortisone group compared with the placebo group. Treatment with a single dose of fludrocortisone results in protection of plasma volume but no protection of orthostatic tolerance. Fludrocortisone is not recommended as a countermeasure for spaceflight-induced orthostatic intolerance.

  2. Orthostatic Hypotension: Epidemiology, Prognosis, and Treatment.

    PubMed

    Ricci, Fabrizio; De Caterina, Raffaele; Fedorowski, Artur

    2015-08-18

    Orthostatic hypotension (OH) is a common cardiovascular disorder, with or without signs of underlying neurodegenerative disease. OH is diagnosed on the basis of an orthostatic challenge and implies a persistent systolic/diastolic blood pressure decrease of at least 20/10 mm Hg upon standing. Its prevalence is age dependent, ranging from 5% in patients <50 years of age to 30% in those >70 years of age. OH may complicate treatment of hypertension, heart failure, and coronary heart disease; cause disabling symptoms, faints, and traumatic injuries; and substantially reduce quality of life. Despite being largely asymptomatic or with minimal symptoms, the presence of OH independently increases mortality and the incidence of myocardial infarction, stroke, heart failure, and atrial fibrillation. In this review, we outline the etiology and prevalence of OH in the general population, summarize its relationship with morbidity and mortality, propose a diagnostic and therapeutic algorithm, and delineate current challenges and future perspectives. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  3. Intravenous Lipid Emulsion Therapy Does Not Improve Hypotension Compared to Sodium Bicarbonate for Tricyclic Antidepressant Toxicity: A Randomized, Controlled Pilot Study in a Swine Model

    DTIC Science & Technology

    2014-11-01

    ORIGINAL CONTRIBUTION Intravenous Lipid Emulsion Therapy Does Not Improve Hypotension Compared to Sodium Bicarbonate for Tricyclic Antidepressant...and chronic pain. Intravenous lipid emulsion (ILE) is a recent antidote for lipophilic drug overdose with unclear effectiveness. ILE has been studied in...Intravenous Lipid Emulsion Therapy Does Not Improve Hypotension Compared to Sodium Bicarbonate for Tricyclic Antidepressant Toxicity: A Randomized, Controlled

  4. Improved management of intradialytic hypotension (IDH) using vitamin E-bonded polysulfone membrane dialyzer.

    PubMed

    Matsumura, Masaki; Sasaki, Hisako; Sekizuka, Kumiko; Sano, Hiroyuki; Ogawa, Kouji; Shimizu, Chihiro; Yoshida, Hiroaki; Kobayashi, Satsuki; Koremoto, Masahide; Aritomi, Masaharu; Ueki, Kazue

    2010-03-01

    Intradialytic hypotension (IDH) is a common clinical trait in hemodialysis (HD) which is caused by poor biocompatibility of the dialyzer membrane. Aiming to improve IDH, vitamin E-bonded polysulfone dialyzer (VPS-H) was evaluated in a pilot study. Eight IDH patients on standard HD were switched from their conventional high-flux dialyzers to VPS-H, and intradialytic blood pressure (BP) was monitored regularly for 10 months. The results showed that hypotension of systolic BP (SBP), diastolic BP (DBP) and pulse pressure (PP) during the session were improved after changing the dialyzer. Notably, almost all the values recorded from 120 minutes into the session until the end of the treatment in the period between the second and tenth month after treatment were significantly different from the corresponding baseline values. Moreover, after 8 to 10 months, the SBP prior to a dialysis session was significantly reduced compared with baseline values. On the other hand, the pulse rate showed no difference throughout the study period. This study provides early evidence of the beneficial role that vitamin E-bonded dialyzers may have in preventing IDH. Larger controlled trials are needed to confirm this original finding.

  5. Arterial baroreflex control of sympathetic nerve activity during acute hypotension: effect of fitness

    NASA Technical Reports Server (NTRS)

    Fadel, P. J.; Stromstad, M.; Hansen, J.; Sander, M.; Horn, K.; Ogoh, S.; Smith, M. L.; Secher, N. H.; Raven, P. B.

    2001-01-01

    We examined arterial baroreflex control of muscle sympathetic nerve activity (MSNA) during abrupt decreases in mean arterial pressure (MAP) and evaluated whether endurance training alters baroreflex function. Acute hypotension was induced nonpharmacologically in 14 healthy subjects, of which 7 were of high fitness (HF) and 7 were of average fitness (AF), by releasing a unilateral arterial thigh cuff after 9 min of resting ischemia under two conditions: control, which used aortic and carotid baroreflex (ABR and CBR, respectively) deactivation; and suction, which used ABR deactivation alone. The application of neck suction to counteract changes in carotid sinus transmural pressure during cuff release significantly attenuated the MSNA response (which increased 134 +/- 32 U/14 s) compared with control (which increased 195 +/- 43 U/14 s) and caused a greater decrease in MAP (19 +/- 2 vs. 15 +/- 2 mmHg; P < 0.05). Furthermore, during both trials, the HF subjects exhibited a greater decrease in MAP compared with AF subjects despite an augmented baroreflex control of MSNA. These data indicate that the CBR contributes importantly to the MSNA response during acute systemic hypotension. Additionally, we suggest that an impaired control of vascular reactivity hinders blood pressure regulation in HF subjects.

  6. Arterial baroreflex control of sympathetic nerve activity during acute hypotension: effect of fitness.

    PubMed

    Fadel, P J; Stromstad, M; Hansen, J; Sander, M; Horn, K; Ogoh, S; Smith, M L; Secher, N H; Raven, P B

    2001-06-01

    We examined arterial baroreflex control of muscle sympathetic nerve activity (MSNA) during abrupt decreases in mean arterial pressure (MAP) and evaluated whether endurance training alters baroreflex function. Acute hypotension was induced nonpharmacologically in 14 healthy subjects, of which 7 were of high fitness (HF) and 7 were of average fitness (AF), by releasing a unilateral arterial thigh cuff after 9 min of resting ischemia under two conditions: control, which used aortic and carotid baroreflex (ABR and CBR, respectively) deactivation; and suction, which used ABR deactivation alone. The application of neck suction to counteract changes in carotid sinus transmural pressure during cuff release significantly attenuated the MSNA response (which increased 134 +/- 32 U/14 s) compared with control (which increased 195 +/- 43 U/14 s) and caused a greater decrease in MAP (19 +/- 2 vs. 15 +/- 2 mmHg; P < 0.05). Furthermore, during both trials, the HF subjects exhibited a greater decrease in MAP compared with AF subjects despite an augmented baroreflex control of MSNA. These data indicate that the CBR contributes importantly to the MSNA response during acute systemic hypotension. Additionally, we suggest that an impaired control of vascular reactivity hinders blood pressure regulation in HF subjects.

  7. Mark-recapture with multiple, non-invasive marks.

    PubMed

    Bonner, Simon J; Holmberg, Jason

    2013-09-01

    Non-invasive marks, including pigmentation patterns, acquired scars, and genetic markers, are often used to identify individuals in mark-recapture experiments. If animals in a population can be identified from multiple, non-invasive marks then some individuals may be counted twice in the observed data. Analyzing the observed histories without accounting for these errors will provide incorrect inference about the population dynamics. Previous approaches to this problem include modeling data from only one mark and combining estimators obtained from each mark separately assuming that they are independent. Motivated by the analysis of data from the ECOCEAN online whale shark (Rhincodon typus) catalog, we describe a Bayesian method to analyze data from multiple, non-invasive marks that is based on the latent-multinomial model of Link et al. (2010, Biometrics 66, 178-185). Further to this, we describe a simplification of the Markov chain Monte Carlo algorithm of Link et al. (2010, Biometrics 66, 178-185) that leads to more efficient computation. We present results from the analysis of the ECOCEAN whale shark data and from simulation studies comparing our method with the previous approaches. © 2013, The International Biometric Society.

  8. Orthostatic Hypotension: Mechanisms, Causes, Management

    PubMed Central

    Tomalia, Victoria A.

    2015-01-01

    Orthostatic hypotension (OH) occurs when mechanisms for the regulation of orthostatic BP control fails. Such regulation depends on the baroreflexes, normal blood volume, and defenses against excessive venous pooling. OH is common in the elderly and is associated with an increase in mortality rate. There are many causes of OH. Aging coupled with diseases such as diabetes and Parkinson's disease results in a prevalence of 10-30% in the elderly. These conditions cause baroreflex failure with resulting combination of OH, supine hypertension, and loss of diurnal variation of BP. The treatment of OH is imperfect since it is impossible to normalize standing BP without generating excessive supine hypertension. The practical goal is to improve standing BP so as to minimize symptoms and to improve standing time in order to be able to undertake orthostatic activities of daily living, without excessive supine hypertension. It is possible to achieve these goals with a combination of fludrocortisone, a pressor agent (midodrine or droxidopa), supplemented with procedures to improve orthostatic defenses during periods of increased orthostatic stress. Such procedures include water bolus treatment and physical countermaneuvers. We provide a pragmatic guide on patient education and the patient-orientated approach to the moment to moment management of OH. PMID:26174784

  9. Role of angiotensin-converting enzyme 2/angiotensin-(1-7)/Mas axis in the hypotensive effect of azilsartan.

    PubMed

    Iwanami, Jun; Mogi, Masaki; Tsukuda, Kana; Wang, Xiao-Li; Nakaoka, Hirotomo; Ohshima, Kousei; Chisaka, Toshiyuki; Bai, Hui-Yu; Kanno, Harumi; Min, Li-Juan; Horiuchi, Masatsugu

    2014-07-01

    The possible counteracting effect of angiotensin (Ang)-converting enzyme (ACE)2/Ang-(1-7)/Mas axis against the ACE/Ang II/Ang II type 1 (AT1) receptor axis in blood pressure control has been previously described. We examined the possibility that this pathway might be involved in the anti-hypertensive effect of a newly developed AT1 receptor blocker (ARB), azilsartan, and compared azilsartan's effects with those of another ARB, olmesartan. Transgenic mice carrying the human renin and angiotensinogen genes (hRN/hANG-Tg) were given azilsartan or olmesartan. Systolic and diastolic blood pressure, as determined by radiotelemetry, were significantly higher in hRN/hANG-Tg mice than in wild-type (WT) mice. Treatment with azilsartan or olmesartan (1 or 5 mg kg(-1) per day) significantly decreased systolic and diastolic blood pressure, and the blood pressure-lowering effect of azilsartan was more marked than that of olmesartan. The urinary Na concentration decreased in an age-dependent manner in hRN/hANG-Tg mice. Administration of azilsartan or olmesartan increased urinary Na concentration, and this effect was weaker with olmesartan than with azilsartan. Azilsartan decreased ENaC-α mRNA expression in the kidney and decreased the ratio of heart to body weight. Olmesartan had a similar but less-marked effect. ACE2 mRNA expression was lower in the kidneys and hearts of hRN/hANG-Tg mice than in WT mice. This decrease in ACE2 mRNA expression was attenuated by azilsartan, but not by olmesartan. These results suggest that the hypotensive and anti-hypertrophic effects of azilsartan may involve activation of the ACE2/Ang-(1-7)/Mas axis with AT1 receptor blockade.

  10. Incidence, Predictors, and Outcomes Associated With Hypotensive Episodes Among Heart Failure Patients Receiving Sacubitril/Valsartan or Enalapril: The PARADIGM-HF Trial (Prospective Comparison of Angiotensin Receptor Neprilysin Inhibitor With Angiotensin-Converting Enzyme Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure).

    PubMed

    Vardeny, Orly; Claggett, Brian; Kachadourian, Jessica; Pearson, Scott M; Desai, Akshay S; Packer, Milton; Rouleau, Jean; Zile, Michael R; Swedberg, Karl; Lefkowitz, Martin; Shi, Victor; McMurray, John J V; Solomon, Scott D

    2018-04-01

    In PARADIGM-HF (Prospective Comparison of Angiotensin Receptor Neprilysin Inhibitor With Angiotensin-Converting Enzyme Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure), heart failure treatment with sacubitril/valsartan reduced the primary composite outcome of cardiovascular death or heart failure hospitalization compared with enalapril but resulted in more symptomatic hypotension. Concern on hypotension may be limiting use of sacubitril/valsartan in appropriate patients. We characterized patients in PARADIGM-HF by whether they reported hypotension during study run-in periods (enalapril, followed by sacubitril/valsartan) and after randomization and assessed whether hypotension modified the efficacy of sacubitril/valsartan. Of the 10 513 patients entering the enalapril run-in, 136 (1.3%) experienced hypotension and 93 (68%) were unable to continue to the next phase; of 9419 patients entering the sacubitril/valsartan run-in period, 228 (2.4%) patients experienced hypotension and 51% were unable to successfully complete the run-in. After randomization, 388 (9.2%) participants had 501 hypotensive events with enalapril, and 588 (14.0%) participants had 803 hypotensive events with sacubitril/valsartan ( P <0.001). There was no difference between randomized treatment groups in the number of participants who discontinued therapy because of hypotension. Individuals with a hypotensive event in either group were older, had lower blood pressure at randomization, and were more likely to have an implantable cardioverter defibrillator. Participants with hypotensive events during run-in who were ultimately randomized derived similar efficacy from sacubitril/valsartan compared with enalapril as those without hypotensive events ( P interaction>0.90). Hypotension was more common with sacubitril/valsartan relative to enalapril in PARADIGM-HF but did not differentially affect permanent discontinuations. Patients with hypotension during run-in derived

  11. Chronic Renin-Angiotensin System (RAS) Blockade May Not Induce Hypotension During Anaesthesia for Bariatric Surgery.

    PubMed

    Salvetti, Guido; Di Salvo, Claudio; Ceccarini, Giovanni; Abramo, Antonio; Fierabracci, Paola; Magno, Silvia; Piaggi, Paolo; Vitti, Paolo; Santini, Ferruccio

    2016-06-01

    The use of angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin II receptor blockers (ARB) for the treatment of hypertensive obese patients is steadily increasing. Some studies have reported that the use of these drugs was associated with an increased risk of hypotensive episodes, during general anaesthesia. The number of bariatric procedures is also increasing worldwide, but there is a lack of studies investigating the hypotensive effect of renin-angiotensin system (RAS) blockers in severely obese patients during general anaesthesia for bariatric surgery. The aim of this pilot study was to evaluate hemodynamic changes induced by general anaesthesia in obese patients chronically treated with ACE-I or ARB compared to a control group not treated with antihypertensive therapy. Fourteen obese subjects (mean body mass index (BMI) 47.5 kg/m(2)) treated with ACE-I or ARB and twelve obese (mean BMI 45.7 kg/m2) controls not treated with antihypertensive therapy underwent general anaesthesia to perform laparoscopic bariatric surgery. Systolic blood pressure, diastolic blood pressure, and heart rate were monitored continuously and registered at different time points: T0 before induction, then at 2, 5, 7, 10, 15, 20, 30, 60, 90, 120, and 150 min after induction, and the last time point taken following recovery from anaesthesia. A progressive reduction of both systolic and diastolic blood pressure values was observed without significant differences between the two groups. A similar trend of heart rate values was observed. In conclusion, our pilot study suggests that RAS blockers may be continued during the perioperative period in patients undergoing bariatric surgery, without increasing the risk of hypotensive episodes.

  12. Cardiovascular Safety of Droxidopa in Patients With Symptomatic Neurogenic Orthostatic Hypotension.

    PubMed

    White, William B; Hauser, Robert A; Rowse, Gerald J; Ziemann, Adam; Hewitt, L Arthur

    2017-04-01

    The norepinephrine prodrug droxidopa improves symptoms of neurogenic orthostatic hypotension, a condition that is associated with diseases of neurogenic autonomic failure (e.g., Parkinson disease, multiple system atrophy, pure autonomic failure). These conditions are more prevalent in older patients who also have cardiovascular co-morbidities. Hence, we evaluated the cardiovascular safety of droxidopa in patients with symptomatic neurogenic orthostatic hypotension who participated in randomized controlled studies (short-term studies of 1 to 2 weeks and an intermediate 8- to 10-week study) and long-term open-label studies. Rates of cardiovascular adverse events (AEs) for patients treated with droxidopa were 4.4% in the intermediate study and 10.8% in the long-term open-label studies. Adjusting for exposure time, cardiovascular AE rates were 0.30 events/patient-year in the short-term and intermediate studies and 0.15 events/patient-year in the long-term open-label studies. The incidence of treatment discontinuation due to blood pressure-related events was approximately 2.5%. Among patients with a history of cardiac disorders at baseline, the rates of cardiovascular-related and blood pressure-related AEs were nominally higher with droxidopa compared to placebo. Most of these events were minor atrial arrhythmias; none were major adverse cardiovascular events or deaths. In conclusion, small increases in cardiovascular AEs were observed with droxidopa compared to placebo; this was most evident in patients with preexisting cardiac disorders. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  13. Temazepam, but not zolpidem, causes orthostatic hypotension in astronauts after spaceflight

    NASA Technical Reports Server (NTRS)

    Shi, Shang-Jin; Garcia, Kathleen M.; Meck, Janice V.

    2003-01-01

    Insomnia is a common symptom, not only in the adult population but also in many astronauts. Hypnotics, such as temazepam (a benzodiazepine) and zolpidem (an imidazopyridine), are often taken to relieve insomnia. Temazepam has been shown clinically to have hemodynamic side effects, particularly in the elderly; however, the mechanism is not clear. Zolpidem does not cause hemodynamic side effects. The purpose of this study was to determine whether the use of different hypnotics during spaceflight might contribute significantly to the high incidence of postflight orthostatic hypotension, and to compare the findings in astronauts with clinical research. Astronauts were separated into three groups: control (n = 40), temazepam (15 or 30 mg; n = 9), and zolpidem (5 or 10 mg; n = 8). In this study, temazepam and zolpidem were only taken the night before landing. The systolic and diastolic blood pressures and heart rates of the astronauts were measured during stand tests before spaceflight and on landing day. On landing day, systolic pressure decreased significantly and heart rate increased significantly in the temazepam group, but not in the control group or in the zolpidem group. Temazepam may aggravate orthostatic hypotension after spaceflight when astronauts are hemodynamically compromised. Temazepam should not be the initial choice as a sleeping aid for astronauts. These results in astronauts may help to explain the hemodynamic side effects in the elderly who are also compromised. Zolpidem may be a better choice as a sleeping aid in these populations.

  14. Hypotensive effect and vascular relaxation in different arteries induced by the nitric oxide donor RuBPY.

    PubMed

    Pereira, Amanda de Carvalho; Araújo, Alice Valença; Paulo, Michele; Andrade, Fernanda Aparecida de; Silva, Bruno Rodrigues; Vercesi, Juliana Aparecida; da Silva, Roberto Santana; Bendhack, Lusiane Maria

    2017-01-30

    NO donors are compounds that release NO that can be used when the endogenous NO bioavailability is impaired. The compound cis-[Ru(bpy) 2 (py)(NO 2 )](PF 6 ) (RuBPY) is a nitrite-ruthenium, since it has a NO 2 in its molecule. The aim of the present study was to evaluate the effect of RuBPY on arterial pressure, as well as on the vascular relaxation of different vascular arteries in renal hypertensive (2K-1C) and normotensive (2K) rats. We have evaluated the arterial pressure and heart rate changes as well as the RuBPY and SNP-induced relaxation (thoracic aorta, mesenteric resistance, coronary and basilar arteries). The administration of RuBPY in awake rats evoked a smaller but long lasting hypotensive effect when compared to SNP, with no increase in heart rate. The relaxation induced by RuBPY was similar between 2K-1C and 2K rats in thoracic aorta, mesenteric resistance and coronary arteries. However, the relaxation induced by RuBPY was smaller in basilar arteries from 2K-1C than in 2K. Taken together, our results show that RuBPY presents several advantages over SNP, since it does not induce hypotensive effect in normotensive animals, the hypotensive effect is slower, with no reflex tachycardia, and it is long lasting. In addition, RuBPY induces coronary artery relaxation (useful for angina) and presented only a small effect on basilar artery (may not induce headache). Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Hypotensive and vasorelaxant effects induced by the ethanolic extract of the Mimosa caesalpiniifolia Benth. (Mimosaceae) inflorescences in normotensive rats.

    PubMed

    Santos, M E P; Moura, L H P; Mendes, M B; Arcanjo, D D R; Monção, N B N; Araújo, B Q; Lopes, J A D; Silva-Filho, J C; Fernandes, R M; Oliveira, R C M; Citó, A M G L; Oliveira, A P

    2015-04-22

    Caatinga is highly influenced by its seasonality. This species is endemic in the northeastern region, which is rich in plants with pharmacological potential. Many of these plants are used by the population and some of them have confirmed pharmacological properties. Mimosa caesalpiniifolia Benth. (Mimosaceae) is a native plant from northeastern Brazil׳s caatinga, popularly known as sabiá and cascudo. The tea from the inflorescence of this species is used by the population of the semi-arid for the treatment of hypertension, and the utilization of the plant bark for the staunching of bleedings and wound washing in order to prevent inflammation; also, the ingestion of the bark infusion is used in the treatment of bronchitis. However, its pharmacological effects and mechanisms of action have not yet been studied. The aim of the present study was to determine the effect of the ethanolic extract of M. caesalpiniifolia on the cardiovascular system in rats. In a study for the assessment of the hypotensive effect of the extract, the polyethylene catheters were inserted in the aorta artery and inferior vena cava for the measurement of the arterial pressure and heart rate. When intragastric administration was performed, only one catheter was implanted in the abdominal aorta. In studies for the vasorelaxant activity, mesenteric arterial rings (1-2mm) were used: they were kept in Tyrode׳s solution (95% O2 and 5% CO2) and submitted to tension of 0.75 g/f for 1h. The results were expressed as mean ± S.E.M., significant to the values of p<0.05. The administration of the doses through venous pathway (6.25; 12.5 and 25mg/kg, i.v.) promoted hypotension followed by bradycardia in the higher doses. The pre-treatment with atropine (2mg/kg, i.v.) interrupted both the hypotension and the bradycardia; with hexamethonium, hypotension was reverted and bradycardia was attenuated. While the administration of tea/flowers (25mg/kg i.v.) also promoted a following section of hypotension, a

  16. Brain Slump Caused by Jugular Venous Stenoses Treated by Stenting: A Hypothesis to Link Spontaneous Intracranial Hypotension with Idiopathic Intracranial Hypertension

    PubMed Central

    Higgins, Nicholas; Trivedi, Rikin; Greenwood, Richard; Pickard, John

    2015-01-01

    Spontaneous intracranial hypotension, of which brain slump is an extreme expression, is caused by a cerebrospinal fluid leak. The reason the leak develops in the first place, however, is unknown, and some cases can be very difficult to manage. We describe a patient with severe symptoms of spontaneous intracranial hypotension and brain slump documented by magnetic resonance imaging whose clinical syndrome and structural brain anomaly resolved completely after treatment directed exclusively at improving cranial venous outflow. Diagnostics included computed tomography (CT) venography, catheter venography, and jugular venoplasty. CT venography showed narrowing of both internal jugular veins below the skull base. Catheter venography confirmed that these were associated with pressure gradients. Jugular venoplasty performed on two separate occasions as a clinical test gave temporary respite. Lasting remission (2 years of follow-up) was achieved by stenting the dominant internal jugular vein. These findings and this outcome suggest a mechanism for the development of spontaneous intracranial hypotension that would link it to idiopathic intracranial hypertension and have cranial venous outflow obstruction as the underlying cause. PMID:26251803

  17. Brain Slump Caused by Jugular Venous Stenoses Treated by Stenting: A Hypothesis to Link Spontaneous Intracranial Hypotension with Idiopathic Intracranial Hypertension.

    PubMed

    Higgins, Nicholas; Trivedi, Rikin; Greenwood, Richard; Pickard, John

    2015-07-01

    Spontaneous intracranial hypotension, of which brain slump is an extreme expression, is caused by a cerebrospinal fluid leak. The reason the leak develops in the first place, however, is unknown, and some cases can be very difficult to manage. We describe a patient with severe symptoms of spontaneous intracranial hypotension and brain slump documented by magnetic resonance imaging whose clinical syndrome and structural brain anomaly resolved completely after treatment directed exclusively at improving cranial venous outflow. Diagnostics included computed tomography (CT) venography, catheter venography, and jugular venoplasty. CT venography showed narrowing of both internal jugular veins below the skull base. Catheter venography confirmed that these were associated with pressure gradients. Jugular venoplasty performed on two separate occasions as a clinical test gave temporary respite. Lasting remission (2 years of follow-up) was achieved by stenting the dominant internal jugular vein. These findings and this outcome suggest a mechanism for the development of spontaneous intracranial hypotension that would link it to idiopathic intracranial hypertension and have cranial venous outflow obstruction as the underlying cause.

  18. Vasopressor Use for Severe Hypotension-A Multicentre Prospective Observational Study.

    PubMed

    Lamontagne, Francois; Cook, Deborah J; Meade, Maureen O; Seely, Andrew; Day, Andrew G; Charbonney, Emmanuel; Serri, Karim; Skrobik, Yoanna; Hebert, Paul; St-Arnaud, Charles; Quiroz-Martinez, Hector; Mayette, Michaël; Heyland, Daren K

    2017-01-01

    The optimal approach to titrate vasopressor therapy is unclear. Recent sepsis guidelines recommend a mean arterial pressure (MAP) target of 65 mmHg and higher for chronic hypertensive patients. As data emerge from clinical trials comparing blood pressure targets for vasopressor therapy, an accurate description of usual care is required to interpret study results. Our aim was to measure MAP values during vasopressor therapy in Canadian intensive care units (ICUs) and to compare these with stated practices and guidelines. In a multicenter prospective cohort study of critically ill adults with severe hypotension, we recorded MAP and vasopressor doses hourly. We investigated variability across patients and centres using multivariable regression models and Analysis of variance (ANOVA), respectively. We included data from 56 patients treated in 6 centers. The mean (standard deviation [SD]) age and Acute Physiology and Chronic Health Evaluation (APACHE) II score were 64 (14) and 25 (8). Half (28 of 56) of the patients were at least 65 years old, and half had chronic hypertension. The patient-averaged MAP while receiving vasopressors was 75 mm Hg (6) and the median (1st quartile, 3rd quartile) duration of vasopressor therapy was 43 hours (23, 84). MAP achieved was not associated with history of underlying hypertension (p = 0.46) but did vary by center (p<0.001). In this multicenter, prospective observational study, the patient-level average MAP while receiving vasopressors for severe hypotension was 75 mmHg, approximately 10 mmHg above current recommendations and stated practices. Moreover, our results do not support the notion that clinicians tailor vasopressor therapy to individual patient characteristics such as underlying chronic hypertension but MAP achieved while receiving vasopressors varied by site.

  19. Suppression of Peripheral Sympathetic Activity Underlies Protease-Activated Receptor 2-Mediated Hypotension

    PubMed Central

    Kim, Young-Hwan; Ahn, Duck-Sun; Joeng, Ji-Hyun

    2014-01-01

    Protease-activated receptor (PAR)-2 is expressed in endothelial cells and vascular smooth muscle cells. It plays a crucial role in regulating blood pressure via the modulation of peripheral vascular tone. Although some reports have suggested involvement of a neurogenic mechanism in PAR-2-induced hypotension, the accurate mechanism remains to be elucidated. To examine this possibility, we investigated the effect of PAR-2 activation on smooth muscle contraction evoked by electrical field stimulation (EFS) in the superior mesenteric artery. In the present study, PAR-2 agonists suppressed neurogenic contractions evoked by EFS in endothelium-denuded superior mesenteric arterial strips but did not affect contraction elicited by the external application of noradrenaline (NA). However, thrombin, a potent PAR-1 agonist, had no effect on EFS-evoked contraction. Additionally, ω-conotoxin GVIA (CgTx), a selective N-type Ca2+ channel (ICa-N) blocker, significantly inhibited EFS-evoked contraction, and this blockade almost completely occluded the suppression of EFS-evoked contraction by PAR-2 agonists. Finally, PAR-2 agonists suppressed the EFS-evoked overflow of NA in endothelium-denuded rat superior mesenteric arterial strips and this suppression was nearly completely occluded by ω-CgTx. These results suggest that activation of PAR-2 may suppress peripheral sympathetic outflow by modulating activity of ICa-N which are located in peripheral sympathetic nerve terminals, which results in PAR-2-induced hypotension. PMID:25598663

  20. Hypotensive effect of aqueous extract of Averrhoa carambola L. (Oxalidaceae) in rats: an in vivo and in vitro approach.

    PubMed

    Soncini, Roseli; Santiago, Michael B; Orlandi, Lidiane; Moraes, Gabriel O I; Peloso, André Luiz M; dos Santos, Marcelo H; Alves-da-Silva, Geraldo; Paffaro, Valdemar A; Bento, Antonio C; Giusti-Paiva, Alexandre

    2011-01-27

    Averrhoa carambola L. (Oxalidaceae) leaves are used in Brazilian traditional medicine to treat hypertension. This study was conducted to evaluate the hypotensive effect of the aqueous extract of Averrhoa carambola (AEAc) and its underlying mechanisms in the isolated rat aorta. The effect of AEAc on the mean arterial pressure (MAP) was determined in vivo in anesthetized rats. In vitro, thoracic aortic rings were isolated and suspended in organ baths, and the effects of AEAc were studied by means of isometric tension recording experiments. In HPLC analysis, the fingerprint chromatogram of AEAc was established. In normotensive rats, AEAc (12.5-50.0 mg/kg, i.v.) induced dose-dependent hypotension. In vitro, AEAc caused a depression in the E(max) response to phenylephrine without a change in sensibility. Also, in a depolarized Ca(2+)-free medium, AEAc inhibited CaCl(2)-induced contractions and caused a concentration-dependent rightward shift of the response curves, indicating that AEAc inhibited the contractile mechanisms involving extracellular Ca(2+) influx. These results demonstrate the hypotensive effects of AEAc, and these effects may, in part, be due to the inhibition of Ca(2+), which supports previous claims of its traditional use. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  1. Effects of the amount of rice in meals on postprandial blood pressure in older people with postprandial hypotension: a within-subjects design.

    PubMed

    Son, Jung Tae; Lee, Eunjoo

    2015-08-01

    To determine the effect of the amount of rice carbohydrates consumed during mealtime on the extent of decrease in postprandial blood pressure in older people with postprandial hypotension. The incidence of postprandial hypotension is as high as 74% in older people with hypertension. A within-subjects repeated measures design was used. Thirty-nine older people in nursing homes received a full serving and a half-serving of rice on two separate days, in random order blood pressure and heart rate were measured before each meal and every 15 minutes for a total of 120 minutes after each meal. Data were analysed using repeated measures analysis of variance and the paired t-test with a Bonferroni adjustment using IBM spss version 19.0. The control and intervention conditions yielded significantly different patterns in systolic blood pressure and diastolic blood pressure. Postprandial hypotension was less frequent under the intervention condition; however, decrease in rice intake did not significantly affect heart rate. Reducing the amount of rice intake per meal prevents postprandial blood pressure decreases in the older people. Small and frequent meals with decreased carbohydrate content are recommended to prevent postprandial hypotension and its complications in the older people. Patients, dieticians and caregivers of older patients should be aware of the importance of diet, especially of decreasing the amount of carbohydrate in a meal. Smaller and more frequent meals are recommended for older people to slow gastric emptying. © 2015 John Wiley & Sons Ltd.

  2. Renal denervation decreases blood pressure and renal tyrosine hydroxylase but does not augment the effect of hypotensive drugs.

    PubMed

    Skrzypecki, Janusz; Gawlak, Maciej; Huc, Tomasz; Szulczyk, Paweł; Ufnal, Marcin

    2017-01-01

    The effect of renal denervation on the efficacy of antihypertensive drugs has not yet been elucidated. Twenty-week-old spontaneously hypertensive rats were treated with metoprolol, losartan, indapamide, or saline (controls) and assigned to renal denervation or a sham procedure. Acute hemodynamic measurements were performed ten days later. Series showing a significant interaction between renal denervation and the drugs were repeated with chronic telemetry measurements. In the saline series, denervated rats showed a significantly lower mean arterial blood pressure (blood pressure) than the sham-operated rats. In contrast, in the metoprolol series denervated rats showed a significantly higher blood pressure than sham rats. There were no differences in blood pressure between denervated and sham rats in the losartan and indapamide series. In chronic studies, a 4-week treatment with metoprolol caused a decrease in blood pressure. Renal denervation and sham denervation performed 10 days after the onset of metoprolol treatment did not affect blood pressure. Denervated rats showed markedly reduced renal nerve tyrosine hydroxylase levels. In conclusion, renal denervation decreases blood pressure in hypertensive rats. The hypotensive action of metoprolol, indapamide, and losartan is not augmented by renal denervation, suggesting the absence of synergy between renal denervation and the drugs investigated in this study.

  3. 18F-FDG PET/CT delayed images with forced diuresis for revaluating abdominopelvic malignancies.

    PubMed

    Wang, Hui-Chun; Wang, Zhi-Min; Wang, Yu-Bin; Chen, Xiao-Hong; Cui, Lan-Lan

    2017-05-01

    The aim of this retrospective study was to evaluate the role of delayed images after forced diuresis coupled with oral hydration in abdominopelvic 18 F-FDG PET/CT. Forty-six patients consisting of 17 urological diseases, 9 gynecological tumors, 18 colorectal malignancies, and 2 cancers of unknown primary site were retrospectively analyzed. All patients who presented with indeterminate or equivocal abdominopelvic foci on standard 18 F-FDG PET/CT underwent a delayed abdominopelvic imaging after administration of 20 mg furosemide intravenously and extra water intake of 500 mL. PET/CT images before and after furosemide were compared with each other and their findings correlated with pathology or clinical follow-up (>6 months). On initial PET/CT, the glucose metabolism characters of lesions were disguised by radioactive urine, or some undetermined 18 F-FDG accumulating foci near the urinary tract appeared. While postdiuretic PET/CT demonstrated an excellent urinary tracer washout, and hypermetabolic lesions could be clearly detected and precisely localized in all cases. On the other hand, the suspected active foci caused by potential stagnation of excreted 18 F-FDG in urinary tract were eliminated. The sensitivity, specificity, and accuracy were 94.4% (34/36), 8/10, 91.3% (42/46), respectively. Furthermore, the additional lesions with surrounding invasion or locoregional metastasis were discovered in 8 of 46 (17.4%) patients only by the delayed images, including 2 gynecological and 6 rectal malignancies. Detection of abdominopelvic malignancies can be improved using delayed 18 F-FDG PET/CT images after a diuretic and oral hydration.

  4. Effects of beach-chair position and induced hypotension on cerebral oxygen saturation in patients undergoing arthroscopic shoulder surgery.

    PubMed

    Lee, Jae Hoon; Min, Kyeong Tae; Chun, Yong-Min; Kim, Eun Jung; Choi, Seung Ho

    2011-07-01

    We investigated the effects of the beach-chair position and induced hypotension on regional cerebral oxygen saturation (rSO(2)) in patients undergoing arthroscopic shoulder surgery by using near-infrared spectroscopy. Twenty-eight patients scheduled for arthroscopic shoulder surgery were enrolled prospectively. After induction of anesthesia, mechanical ventilation was controlled to maintain Paco(2) at 35 to 40 mm Hg. Anesthesia was maintained with sevoflurane and remifentanil. After radial artery cannulation, mean arterial pressure (MAP) was measured at the external auditory meatus level and maintained between 60 and 65 mm Hg. The rSO(2) was measured by use of near-infrared spectroscopy. MAP and rSO(2) were recorded at the following times: before induction (T(0)), immediately after induction (T(1) [baseline]), after beach-chair position (T(2)), immediately after induced hypotension (T(3)), 1 hour after induced hypotension (T(4)), and after supine position at the end of surgery (T(5)). Cerebral desaturation was defined as a reduction in rSO(2) to less than 80% of baseline value for 15 seconds or greater. A total of 27 patients were evaluated until the end of this study. The MAP at T(2) was significantly lower than that at T(1). The MAP values at T(3) and T(4) were significantly lower than those at T(1) and T(2). The rSO(2) at T(2) was significantly lower than that at T(1). Unlike the pattern of change in the MAP, there was no additional decrease in rSO(2) at T(3) and T(4). There were 2 patients who had an episode of cerebral desaturation. The beach-chair position combined with induced hypotension significantly decreases rSO(2) in patients undergoing shoulder arthroscopic surgery under general anesthesia. Level IV, study of nonconsecutive patients without consistently applied reference gold standard. Copyright © 2011 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  5. Pathophysiology and management of spontaneous intracranial hypotension--a review.

    PubMed

    Syed, Nadir Ali; Mirza, Farhan Arshad; Pabaney, Aqueel Hussain; Rameez-ul-Hassan

    2012-01-01

    Spontaneous Intracranial Hypotension is a syndrome involving reduced intracranial pressure secondary to a dural tear which occurs mostly due to connective tissue disorders such as Marfans Syndrome, and Ehler Danlos Syndrome. Patients with dural ectasias leading to CSF leakage into the subdural or epidural space classically present with orthostatic headaches and cranial nerve deficits mostly seen in cranial nerves V-VIII. Diagnosis of SIH is confirmed with the aid of neuroimaging modalities of which Cranial MR imaging is most widely used. SIH can be treated conservatively or with epidural blood patches which are now widely being used to repair dural tears, and their effectiveness is being recognized. Recently epidural injection of fibrin glue has also been used which has been found to be effective in certain patients.

  6. Antioxidant and Vasodilator Activity of Ugni molinae Turcz. (Murtilla) and Its Modulatory Mechanism in Hypotensive Response

    PubMed Central

    Jofré, Ignacio; Pezoa, Cesar; Scheuermann, Erick; Rosalen, Pedro Luiz; Romero, Fernando

    2016-01-01

    Hypertension is a systemic condition with high morbidity and mortality rates worldwide, which poses an increased risk for cardiovascular diseases. In this study, we demonstrated the antioxidant and vasodilator activity of Ugni molinae Turcz. (Murtilla) fruit, a berry native to Chile and proposed models to explain its modulatory mechanism in hypotensive response. Murtilla fruits were cultivated in a germplasm bank and submitted to chemical and biological analyses. The phenolic compounds gallic acid, Catechin, Quercetin-3-β-D-glucoside, Myricetin, Quercetin, and Kaempferol were identified. Murtilla extract did not generate toxic effects on human endothelial cells and had significant antioxidant activity against ROS production, lipid peroxidation, and superoxide anion production. Furthermore, it showed dose-dependent vasodilator activity in aortic rings in the presence of endothelium, whose hypotensive mechanism is partially mediated by nitric oxide synthase/guanylate cyclase and large-conductance calcium-dependent potassium channels. Murtilla fruits might potentially have beneficial effects on the management of cardiovascular diseases. PMID:27688827

  7. Hypotensive effects of hawthorn for patients with diabetes taking prescription drugs: a randomised controlled trial

    PubMed Central

    Walker, Ann F; Marakis, Georgios; Simpson, Eleanor; Hope, Jessica L; Robinson, Paul A; Hassanein, Mohamed; Simpson, Hugh CR

    2006-01-01

    Background Hawthorn (Crataegus laevigata) leaves, flowers and berries are used by herbal practitioners in the UK to treat hypertension in conjunction with prescribed drugs. Small-scale human studies support this approach. Aim To investigate the effects of hawthorn for hypertension in patients with type 2 diabetes taking prescribed drugs. Design of study Randomised controlled trial. Setting General practices in Reading, UK. Method Patients with type 2 diabetes (n = 79) were randomised to daily 1200 mg hawthorn extract (n = 39) or placebo (n = 40) for 16 weeks. At baseline and outcome a wellbeing questionnaire was completed and blood pressure and fasting blood samples taken. A food frequency questionnaire estimated nutrient intake. Results Hypotensive drugs were used by 71% of the study population with a mean intake of 4.4 hypoglycaemic and/or hypotensive drugs. Fat intake was lower and sugar intake higher than recommendations, and low micronutrient intake was prevalent. There was a significant group difference in mean diastolic blood pressure reductions (P = 0.035): the hawthorn group showed greater reductions (baseline: 85.6 mmHg, 95% confidence interval [CI] = 83.3 to 87.8; outcome: 83.0 mmHg, 95% CI = 80.5 to 85.7) than the placebo group (baseline: 84.5 mmHg, 95% CI = 82 to 87; outcome: 85.0 mmHg, 95% CI = 82.2 to 87.8). There was no group difference in systolic blood pressure reduction from baseline (3.6 and 0.8 mmHg for hawthorn and placebo groups, respectively; P = 0.329). Although mean fat intake met current recommendations, mean sugar intake was higher and there were indications of potential multiple micronutrient deficiencies. No herb–drug interaction was found and minor health complaints were reduced from baseline in both groups. Conclusions This is the first randomised controlled trial to demonstrate a hypotensive effect of hawthorn in patients with diabetes taking medication. PMID:16762125

  8. Hypotensive effects of hawthorn for patients with diabetes taking prescription drugs: a randomised controlled trial.

    PubMed

    Walker, Ann F; Marakis, Georgios; Simpson, Eleanor; Hope, Jessica L; Robinson, Paul A; Hassanein, Mohamed; Simpson, Hugh C R

    2006-06-01

    Hawthorn (Crataegus laevigata) leaves, flowers and berries are used by herbal practitioners in the UK to treat hypertension in conjunction with prescribed drugs. Small-scale human studies support this approach. To investigate the effects of hawthorn for hypertension in patients with type 2 diabetes taking prescribed drugs. Randomised controlled trial. General practices in Reading, UK. Patients with type 2 diabetes (n = 79) were randomised to daily 1200 mg hawthorn extract (n = 39) or placebo (n = 40) for 16 weeks. At baseline and outcome a wellbeing questionnaire was completed and blood pressure and fasting blood samples taken. A food frequency questionnaire estimated nutrient intake. Hypotensive drugs were used by 71% of the study population with a mean intake of 4.4 hypoglycaemic and/or hypotensive drugs. Fat intake was lower and sugar intake higher than recommendations, and low micronutrient intake was prevalent. There was a significant group difference in mean diastolic blood pressure reductions (P = 0.035): the hawthorn group showed greater reductions (baseline: 85.6 mmHg, 95% confidence interval [CI] = 83.3 to 87.8; outcome: 83.0 mmHg, 95% CI = 80.5 to 85.7) than the placebo group (baseline: 84.5 mmHg, 95% CI = 82 to 87; outcome: 85.0 mmHg, 95% CI = 82.2 to 87.8). There was no group difference in systolic blood pressure reduction from baseline (3.6 and 0.8 mmHg for hawthorn and placebo groups, respectively; P = 0.329). Although mean fat intake met current recommendations, mean sugar intake was higher and there were indications of potential multiple micronutrient deficiencies. No herb-drug interaction was found and minor health complaints were reduced from baseline in both groups. This is the first randomised controlled trial to demonstrate a hypotensive effect of hawthorn in patients with diabetes taking medication.

  9. Mark-resight abundance estimation under incomplete identification of marked individuals

    USGS Publications Warehouse

    McClintock, Brett T.; Hill, Jason M.; Fritz, Lowell; Chumbley, Kathryn; Luxa, Katie; Diefenbach, Duane R.

    2014-01-01

    Often less expensive and less invasive than conventional mark–recapture, so-called 'mark-resight' methods are popular in the estimation of population abundance. These methods are most often applied when a subset of the population of interest is marked (naturally or artificially), and non-invasive sighting data can be simultaneously collected for both marked and unmarked individuals. However, it can often be difficult to identify marked individuals with certainty during resighting surveys, and incomplete identification of marked individuals is potentially a major source of bias in mark-resight abundance estimators. Previously proposed solutions are ad hoc and will tend to underperform unless marked individual identification rates are relatively high (>90%) or individual sighting heterogeneity is negligible.Based on a complete data likelihood, we present an approach that properly accounts for uncertainty in marked individual detection histories when incomplete identifications occur. The models allow for individual heterogeneity in detection, sampling with (e.g. Poisson) or without (e.g. Bernoulli) replacement, and an unknown number of marked individuals. Using a custom Markov chain Monte Carlo algorithm to facilitate Bayesian inference, we demonstrate these models using two example data sets and investigate their properties via simulation experiments.We estimate abundance for grassland sparrow populations in Pennsylvania, USA when sampling was conducted with replacement and the number of marked individuals was either known or unknown. To increase marked individual identification probabilities, extensive territory mapping was used to assign incomplete identifications to individuals based on location. Despite marked individual identification probabilities as low as 67% in the absence of this territorial mapping procedure, we generally found little return (or need) for this time-consuming investment when using our proposed approach. We also estimate rookery abundance

  10. [Orthostatic hypotension in the elderly].

    PubMed

    Ferrer-Gila, Teresa; Rízea, Cristian

    2013-03-16

    Orthostatic hypotension (OH) is defined as a decrease in systolic blood pressure of 20 mmHg, or a decrease in diastolic blood pressure of 10 mmHg within three minutes of standing. It results from an inadequate response to postural changes in blood pressure. Common symptoms include dizziness, light-headedness, blurred vision, weakness, fatigue, nausea, palpitations, sweating, head and neck ache, slow cognitive performance and transient loss of conscientiousness. OH is a common problem among elderly patients and its aetiology is diverse, including autonomic nervous system dysfunction, cardiac problems, medication side effects, ageing changes or transitory deregulation of blood volume. The instrumental diagnosis can be easily accomplished by the tilt-table test, with continuous monitoring of blood pressure and cardiac parameters. It is a non-invasive technique and needs minimal collaboration from the patient. In our experience, when reviewing 327 patients, aged over 40 years and examined because of clinical suspicion of OH, the prevalence thereof was 51% whereas if focused in subjects older than 70, OH was proven in 90% of the cases. The older the patients, the more frequently they presented general deterioration, neurological or cardiac problems as well as pharmacological side effects. Ruling out neurological or cardiac malfunction can drastically improve the prognosis with possible reversibility of symptoms. Some nonpharmacological and pharmacological approaches to improve management of OH and life quality are described for guidance.

  11. Evaluation of cerebral vasomotor reactivity in Parkinson's disease: is there any association with orthostatic hypotension?

    PubMed

    Zamani, Babak; Mehrabani, Mehrnoush; Fereshtehnejad, Seyed-Mohammad; Rohani, Mohammad

    2011-06-01

    Our aim was to look for a probable relationship between cerebral vasomotor reactivity (VMR) and orthostatic hypotension (OH) in Parkinson's disease (PD). This study was conducted on 44 patients with PD. Assessment of cerebral VMR was performed by means of transcranial Doppler (TCD) of middle cerebral artery (MCA) before and after a vasodilatory stimulus, carbon dioxide test. Moreover, orthostatic hypotension was evaluated. OH was presented in 12 (27.3%) Parkinson's patients. The average resting blood flow velocity (BFV) in the MCA was 30.20 (SD=9.58)cms(-1) which significantly increased to 46.25 (SD=16.23)cms(-1) after carbon dioxide test (P<0.001). Impaired VMR was observed in 15 (34.1%) of the subjects, while it was not associated with the presence of OH (P=0.770). Evaluation of VMR in patients affected by PD, could assist in early diagnosis of cerebral autonomic dysfunction and prevent its serious consequences prior and more valid to OH. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.

  12. The Role of Permissive and Induced Hypotension in Current Neuroanesthesia Practice.

    PubMed

    Soghomonyan, Suren; Stoicea, Nicoleta; Sandhu, Gurneet S; Pasternak, Jeffrey J; Bergese, Sergio D

    2017-01-01

    Induced hypotension (IH) had been used for decades in neurosurgery to reduce the risk for intraoperative blood loss and decrease blood replacement. More recently, this method fell out of favor because of concerns for cerebral and other end-organ ischemia and worse treatment outcomes. Other contributing factors to the decline in its popularity include improvements in microsurgical technique, widespread use of endovascular procedures, and advances in blood conservation and transfusion protocols. Permissive hypotension (PH) is still being used occasionally in neurosurgery; however, its role in current anesthesia practice remains unclear. Our objective was to describe contemporary utilization of IH and PH (collectively called PH) in clinical practice among members of the Society for Neuroscience in Anesthesiology and Critical Care (SNACC). A questionnaire was developed and distributed among SNACC members that addressed practice patterns related to the use of PH. The responses were analyzed based on the number of individuals who responded to each specific question. Of 72 respondents, 67.6% reported over 10 years of clinical experience, while 15.5% reported 5-10 years of post-training experience. The respondents admitted to providing anesthesia for 300 (median) neurosurgical cases per year. PH was applied most commonly during open interventions on cerebral aneurysms (50.8%) and arteriovenous malformations (46%). Seventy-three percent of respondents were not aware of any complications in their practice attributable to PH. PH is still being used in neuroanesthesia practice by some providers. Further research is justified to clarify the risks and benefits of PH in modern neuroanesthesia practice.

  13. Neurogenic orthostatic hypotension: roles of norepinephrine deficiency in its causes, its treatment, and future research directions.

    PubMed

    Loavenbruck, Adam; Sandroni, Paola

    2015-11-01

    Although a diversity of neurotransmitters and hormones participate in controlling blood pressure, norepinephrine released from postganglionic sympathetic nerve terminals is an important mediator of the rapid regulation of cardiovascular function required for homeostasis of cerebral perfusion. Hence, neurogenic orthostatic hypotension (NOH) often represents a deficiency of noradrenergic responsiveness to postural change. PubMed searches with 'orthostatic hypotension' and 'norepinephrine' as conjoint search terms and no restriction on language or date, so as to survey the pathophysiologic and clinical relevance of norepinephrine deficiency for current NOH interventions and for future directions in treatment and research. Norepinephrine deficiency in NOH can arise peripherally, due to cardiovascular sympathetic denervation (as in pure autonomic failure, Parkinson's disease, and a variety of neuropathies), or centrally, due to a failure of viscerosensory signals to generate adequate sympathetic traffic to intact sympathetic nerve endings (as in multiple system atrophy). Nonpharmacologic countermeasures such as pre-emptive water intake may yield blood-pressure increases exceeding those achieved pharmacologically. For patients with symptomatic NOH unresponsive to such strategies, a variety of pharmacologic interventions have been administered off-label on the basis of drug mechanisms expected to increase blood pressure via blood-volume expansion or vasoconstriction. Two pressor agents have received FDA approval: the sympathomimetic midodrine and more recently the norepinephrine prodrug droxidopa. Pressor agents are important for treating symptomatic NOH in patients unresponsive to lifestyle changes alone. However, the dysautonomia underlying NOH often permits blood-pressure excursions toward both hypotension and hypertension. Future research should aim to shed light on the resulting management issues, and should also explore the possibility of pharmacotherapy selectively

  14. Glyburide, a K(+)(ATP)channel blocker, improves hypotension and survival in anaphylactic shock induced in Wistar rats sensitized to ovalbumin.

    PubMed

    Dhanasekaran, Subramanian; Nemmar, Abderrahim; Aburawi, Elhadi H; Kazzam, Elsadig E; Abdulle, Abdishakur; Bellou, Moufida; Bellou, Abdelouahab

    2013-11-15

    Allergens can induce anaphylactic shock and death due to serve hypotension. Potassium channel blockers (K(+)(ATP)) such as glyburide (GLY) induce vasoconstriction. The effect of (K(+)(ATP)) channel blockers on anaphylactic shock is poorly understood. Objective of the study was to test the hypothesis that GLY reduces hypotension induced in anaphylactic shock and increases survival. Rats were grouped into: G1-N=Naïve; G2-SC=Sensitized-Control; G3-SG=Sensitized-GLY (glyburide 40 mg/kg); G4-SE=Sensitized-EPI (epinephrine 10 mg/kg). G2 to G4 groups were sensitized with ovalbumin (OVA) and shock was induced by i.v. injection of OVA. Treatments were administered intravenously 5 min later. Mean arterial pressure (MAP), heart rate (HR), and mean survival time (MST) were measured for 60 min following OVA injection and treatments administration. At the end of the experiment, blood withdrawal was performed to measure plasma levels of histamine, leukotriene B(4) (LTB(4)), prostaglandin E(2) (PGE(2)) and prostaglandin F(2) (PGF(2)). Additionally blood gas (paO2, paCO2, SaO2) and electrolytes (Na(+), K(+) and Ca (++)) were measured. MAP was normal in G1-N; severe hypotension, negative inotropic and short MST were observed in G2-SC; normalization of MAP, with lesser negative inotropism and increased MST were observed in G3-SG; full recovery was observed in G4-SE. Histamine level was significantly higher in G2-SC; reduced in G3-SG and G4-SE. PGE(2) increased in G3-SG; PGF(2) increased in G2-SC and G3-SG. Na(+) and Ca (++) concentration decreased in sensitized rats but reversed in treated groups, without change in K(+) concentration. In conclusion, our data suggest that administration of GLY reduced hypotension and increases survival time in rat anaphylactic shock.

  15. Hypotensive effects of hemopressin and bradykinin in rabbits, rats and mice. A comparative study.

    PubMed

    Blais, Paul-André; Côté, Jérôme; Morin, Josée; Larouche, Annie; Gendron, Gabrielle; Fortier, Audrey; Regoli, Domenico; Neugebauer, Witold; Gobeil, Fernand

    2005-08-01

    Hemopressin is a novel vasoactive nonapeptide derived from hemoglobin's alpha-chain as recently reported by Rioli et al. [Rioli V, Gozzo FC, Heimann AS, Linardi A, Krieger JE, Shida CS, et al. Novel natural peptide substrates for endopeptidase 24.15, neurolysin, and angiotensin-converting enzyme. J Biol Chem 2003;278(10):8547-55]. In anesthetized male Wistar rats, this peptide exhibited hypotensive actions similar to those of bradykinin (BK) when administered intravenously (i.v.), and was found to be metabolized both in vitro and in vivo by several peptidases, including the angiotensin-converting enzyme (ACE). In this study, these findings were expanded upon by examining: (i) the degradation kinetics following incubation with ACE purified from rabbit lung and (ii) the blood pressure lowering effects of HP and BK injected i.v. or intra-arterially (i.a.) in male rabbits, rats, and mice. Our findings demonstrate that, in vitro, HP and BK are both degraded by ACE, but at different velocity rates. Furthermore, both HP and BK induced transient hypotension in all animals tested, although the responses to HP relative to the administration sites were significantly lower (by 10-100-fold) on an equimolar basis compared to those of BK. In rabbits, the decrease of blood pressure induced by HP (10-100 nmol/kg) did not differ whether it was administered i.v. or i.a., suggesting an absence of pulmonary/cardiac inactivation in contrast to BK (0.1-1 nmol/kg). The in vivo effect of HP was significantly potentiated in rabbits immunostimulated with bacterial lipopolysaccharide (LPS), but was unaffected by both the B2 receptor antagonist HOE 140 (0.1 micromol/kg) and captopril (100 microg/kg), contrary to BK. Therefore, HP acts as a weak hypotensive mediator, which does not activate kinin B2 receptors, but uses a functional site and/or signaling paths appearing to be up-regulated by LPS.

  16. Role of physical countermaneuvers in the management of orthostatic hypotension: efficacy and biofeedback augmentation

    NASA Technical Reports Server (NTRS)

    Bouvette, C. M.; McPhee, B. R.; Opfer-Gehrking, T. L.; Low, P. A.

    1996-01-01

    OBJECTIVE: To evaluate the efficacy of various physical countermaneuvers in reducing orthostatic hypotension and its associated symptoms and to assess the efficacy of biofeedback training in enhancing the effectiveness of physical countermaneuvers. MATERIAL AND METHODS: In nine study subjects with neurogenic orthostatic hypotension, four training sessions on physical countermaneuvers were performed after tilt-up, three with visual feedback on the effect of physical countermaneuvers on blood pressure and other cardiovascular variables. Blood pressure change and orthostatic symptoms during tilt-up were determined, as were the changes in total peripheral resistance, stroke index, and heart rate. RESULTS: The five female and four male patients had a mean age of 53 years and a mean duration of symptoms of 4.2 years. On an orthostatic symptom scale of 0 to 10, these patients had a mean symptom score of 7.3. The increment in systolic blood pressure was better for some maneuvers (such as leg crossing and a combination) than others (such as neck flexion and abdominal contraction). Three patterns of responses to biofeedback were found. Simple maneuvers such as squatting did not improve with training; visual feedback was needed for maneuvers such as thigh contraction, and performance declined without biofeedback; the third pattern, seen in maneuvers such as leg crossing, showed continued improvement with training, even without biofeedback. A survey at 3 to 4 months after training revealed continued use of physical maneuvers (3.8 +/- 3.1 per day), increased standing time with each episode of presyncopal symptoms (8.3 +/- 5.8 minutes), and continued global symptomatic improvement. Total peripheral resistance, but not heart rate or stroke index, showed significant regression with blood pressure improvement. CONCLUSION: Physical countermaneuvers are efficacious in reducing orthostatic hypotension, can be augmented by use of biofeedback, and may significantly improve the

  17. Camphor-Crataegus berry extract combination dose-dependently reduces tilt induced fall in blood pressure in orthostatic hypotension.

    PubMed

    Belz, G G; Butzer, R; Gaus, W; Loew, D

    2002-10-01

    In order to test the efficacy of a combination of natural D-camphor and an extract of fresh crataegus berries (Korodin Herz-Kreislauf-Tropfen) on orthostatic hypotension, two similar, controlled, randomized studies were carried out in a balanced crossover design in 24 patients each with orthostatic dysregulation. The camphor-crataegus berry combination (CCC) was orally administered as a single regimen in 3 different dosages of 5 drops, 20 drops and 80 drops; a placebo with 20 drops of a 60% alcoholic solution served as control. Orthostatic hypotension was assessed with the tilt table test before and after medication. Source data of both studies were pooled and meta-analytically evaluated for all 48 patients. CCC drops decreased the orthostatic fall in blood pressure versus placebo, as almost uniformly established at all times by mean arterial pressure and diastolic blood pressure. Mean arterial pressure demonstrated the very fast onset of action by a clearly dose-dependent statistically significant effect even after 1-minute orthostasis. Increase of mean arterial pressure as compared to the orthostasis test before medication was on average 4.5 mmHg. CCC affected diastolic blood pressure after 1 minute of orthostasis in all dosages as compared to placebo. A statistically significant effect of the highest dose of 80 drops on diastolic blood pressure could be demonstrated after 1-, 3-, and 5-minute orthostasis. The hemodynamic findings of a stabilizing effect on arterial pressure in orthostasis corroborate the long-term medical experience with CCC and justify the indication orthostatic hypotension.

  18. Intracranial hypotension and hypertension in children and adolescents.

    PubMed

    Ozge, Aynur; Bolay, Hayrunnisa

    2014-07-01

    The specific aim of this review is to report the features of intracranial pressure changes [spontaneous intracranial hypotension (SIH) and idiopathic intracranial hypertension (IIH)] in children and adolescents, with emphasis on the presentation, diagnosis, and treatment modalities. Headache associated with intracranial pressure changes are relatively rare and less known in children and adolescents. SIH is a specific syndrome involving reduced intracranial pressure with orthostatic headache, frequently encountered connective tissue disorders, and a good prognosis with medical management, initial epidural blood patching, and sometimes further interventions may be required. IIH is an uncommon condition in children and different from the disease in adults, not only with respect to clinical features (likely to present with strabismus and stiff neck rather than headache or pulsatile tinnitus) but also different in outcome. Consequently, specific ICP changes of pediatric ages required specific attention both of exact diagnosis and entire management.

  19. Agonistic autoantibodies as vasodilators in orthostatic hypotension: a new mechanism.

    PubMed

    Li, Hongliang; Kem, David C; Reim, Sean; Khan, Muneer; Vanderlinde-Wood, Megan; Zillner, Caitlin; Collier, Daniel; Liles, Campbell; Hill, Michael A; Cunningham, Madeleine W; Aston, Christopher E; Yu, Xichun

    2012-02-01

    Agonistic autoantibodies to the β-adrenergic and muscarinic receptors are a novel investigative and therapeutic target for certain orthostatic disorders. We have identified the presence of autoantibodies to β2-adrenergic and/or M3 muscarinic receptors by ELISA in 75% (15 of 20) of patients with significant orthostatic hypotension. Purified serum IgG from all 20 of the patients and 10 healthy control subjects were examined in a receptor-transfected cell-based cAMP assay for β2 receptor activation and β-arrestin assay for M3 receptor activation. There was a significant increase in IgG-induced activation of β2 and M3 receptors in the patient group compared with controls. A dose response was observed for both IgG activation of β2 and M3 receptors and inhibition of their activation with the nonselective β blocker propranolol and muscarinic blocker atropine. The antibody effects on β2 and/or M3 (via production of NO) receptor-mediated vasodilation were studied in a rat cremaster resistance arteriole assay. Infusion of IgG from patients with documented β2 and/or M3 receptor agonistic activity produced a dose-dependent vasodilation. Sequential addition of the β-blocker propranolol and the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester partially inhibited IgG-induced vasodilation (percentage of maximal dilatory response: from 57.7±10.4 to 35.3±4.6 and 24.3±5.8, respectively; P<0.01; n=3), indicating that antibody activation of vascular β2 and/or M3 receptors may contribute to systemic vasodilation. These data support the concept that circulating agonistic autoantibodies serve as vasodilators and may cause or exacerbate orthostatic hypotension.

  20. Integrated analysis of droxidopa trials for neurogenic orthostatic hypotension.

    PubMed

    Biaggioni, Italo; Arthur Hewitt, L; Rowse, Gerald J; Kaufmann, Horacio

    2017-05-12

    Droxidopa, a prodrug of norepinephrine, was approved for treatment of neurogenic orthostatic hypotension (nOH) due to primary autonomic disorders based on 3 randomized double-blind studies. We performed safety and efficacy analyses of this pooled dataset (n = 460). Efficacy was assessed using Orthostatic Hypotension Questionnaire (OHQ) scores (composite and individual items). Safety and tolerability were also examined. Droxidopa improved virtually all nOH symptom scores compared with placebo, significantly reducing OHQ composite score (-2.68 ± 2.20 vs -1.82 ± 2.34 units; P < 0.001), dizziness/lightheadedness score (-3.0 ± 2.9 vs -1.8 ± 3.1 units; P < 0.001), and 3 of 5 other symptom assessments (visual disturbances, weakness, and fatigue [P ≤ 0.010]). Droxidopa significantly improved 3 of 4 measures of activities of daily living (standing a long time, walking a short time, and walking a long time [P ≤ 0.003]) and significantly increased upright systolic blood pressure (11.5 ± 20.5 vs 4.8 ± 21.0 mmHg for placebo; P < 0.001). Droxidopa was effective in patients using inhibitors of dopa decarboxylase (DDCI; the enzyme that converts droxidopa to norepinephrine), but its efficacy was numerically greater in non-DDCI users. Droxidopa was well-tolerated. Rates of most adverse events were similar between groups. Supine hypertension rates were low, but slightly higher in patients receiving droxidopa (≤7.9% vs ≤4.6% for placebo); patients with severe hypertension at screening were excluded from these studies. Droxidopa is effective for the treatment of nOH in patients with primary autonomic disorders and is generally well-tolerated. A longer trial is underway to confirm efficacy beyond the ≤2 to 10 - week period assessed in the current trials. ClinicalTrials.gov identifiers: NCT00782340 , first received October 29, 2008; NCT00633880 , first received March 5, 2008; and NCT01176240 , first received July 30, 2010.

  1. Natural products with hypoglycemic, hypotensive, hypocholesterolemic, antiatherosclerotic and antithrombotic activities.

    PubMed

    Wang, H X; Ng, T B

    1999-01-01

    This article reviews compounds of botanical origin which are capable of lowering plasma levels of glucose and cholesterol and blood pressure, as well as compounds inhibiting atherosclerosis and thrombosis. Hypoglycemic natural products comprise flavonoids, xanthones, triterpenoids, alkaloids, glycosides, alkyldisulfides, aminobutyric acid derivatives, guanidine, polysaccharides and peptides. Hypotensive compounds include flavonoids, diterpenes, alkaloids, glycosides, polysaccharides and proteins. Among natural products with hypocholesterolemic activity are beta-carotene, lycopene, cycloartenol, beta-sitosterol, sitostanol, saponin, soybean protein, indoles, dietary fiber, propionate, mevinolin (beta-hydroxy-beta-methylglutaryl coenzyme A reductase inhibitor) and polysaccharides. Heparins, flavonoids, tocotrienols, beta-hydroxy-beta-methylglutaryl coenzyme A reductase inhibitors (statins), garlic compounds and fungal proteases exert antithrombotic action. Statins and garlic compounds also possess antiatherosclerotic activity.

  2. The use of antigravity suits in the treatment of idiopathic orthostatic hypotension

    NASA Technical Reports Server (NTRS)

    Landmark, K.; Kravik, S.

    1980-01-01

    Idiopathic orthostatic hypotension is an uncommon disease characterized by a drop in blood pressure when going from a recumbent to a standing position. Treatment by medication generally produces poor results. Three patients at the Royal Hospital in Oslo were treated with antigravity suits and all were able to maintain adequate blood pressures in the standing position. One patient improved dramatically and was able to take short walks while wearing the suit. The two other patients, however, felt that wearing the suits eventually became uncomfortable. This treatment represents a useful treatment alternative for intractable cases.

  3. Mark.

    ERIC Educational Resources Information Center

    Lipman, Matthew; Smith, Theresa L., Ed.

    Mark is the central character in this story designed to help adolescents formulate a philosophy of values. The story is well suited for use in high school social studies courses and/or in philosophy or guidance units. Mark's thoughts and actions are reported as he interacts with his family, friends, acquaintances, and individuals of authority…

  4. Evaluation of Hypotensive and Antihypertensive Effects of Velvet Bean (Mucuna pruriens L.) Hydrolysates.

    PubMed

    Chel-Guerrero, Luis; Galicia-Martínez, Saulo; Acevedo-Fernández, Juan José; Santaolalla-Tapia, Jesus; Betancur-Ancona, David

    2017-01-01

    Hypertension could cause significant worldwide health problems that affect 15-20% of all adults; according to National Health and Nutrition Examination Survey, about 29% of the adult population in the United States are hypertensive. Recent research has shown that peptides derived from the hydrolysis of food proteins can decrease blood pressure. This study was carried out to evaluate the hypotensive and antihypertensive potential of Mucuna pruriens protein hydrolysates in in vitro and in vivo models. M. pruriens protein concentrate was prepared by wet fractionation and enzymatically hydrolyzed using Alcalase ® , Flavourzyme ® , and the sequential system Alcalase-Flavourzyme at different times (5-120 min). The biological potential was measured in vitro based on the IC 50 value as well as in vivo effect, measuring the systolic (SBP) and diastolic (DBP) blood pressure in normotensive and antihypertensive Wistar-Kyoto rats by the tail-cuff method. Hydrolysis of M. pruriens protein concentrates with commercial enzymes generated extensive hydrolysates with angiotensin-converting enzyme (ACE-I) inhibitory activity (IC 50 : 0.589-0.993 mg/mL) and hypotensive (SBP: 0.6-47.43%, DBP: 1.94-43.47%) and antihypertensive (SBP: 8.84-27.29% DBP: 16.1-29.37%) effect. These results indicate that Mucuna pruriens protein hydrolysate (MPPH) could be used as a functional ingredient to prevent blood pressure increase.

  5. Adding hydrocortisone as 1st line of inotropic treatment for hypotension in very low birth weight infants.

    PubMed

    Hochwald, Ori; Palegra, Gustavo; Osiovich, Horacio

    2014-08-01

    In this pilot study the authors demonstrate the feasibility, effectiveness and safety of the combined early treatment with hydrocortisone and dopamine for refractory hypotension in preterm newborns. Very low birth weight infants born at gestational age < 30 wk or birth weight < 1250 g in the first 48 h of life with hypotension after receiving 10-20 mL/kg bolus of normal saline, were randomized to receive concurrently with the initiation of dopamine, intravenous hydrocortisone (11 infants) or an equivalent volume of placebo (11 infants). Despite no significant clinical difference between the groups including gestational age, birth weight, prevalence of chorioamnionitis, prenatal steroid treatment, cord PH, baseline cortisol level, there was a trend towards lower incidence of bronchopulmonary dysplasia (BPD), and higher survival without BPD rate in the hydrocortisone group. In this very sick small group of infants, hydrocortisone was not associated with more adverse effects, but rather showed a trend toward association with better outcome, including survival without BPD.

  6. Enamel-based mark performance for marking Chinese mystery snail Bellamya chinensis

    USGS Publications Warehouse

    Wong, Alec; Allen, Craig R.; Hart, Noelle M.; Haak, Danielle M.; Pope, Kevin L.; Smeenk, Nicholas A.; Stephen, Bruce J.; Uden, Daniel R.

    2013-01-01

    The exoskeleton of gastropods provides a convenient surface for carrying marks, and i the interest of improving future marking methods our laboratory assessed the performance of an enamel paint. The endurance of the paint was also compared to other marking methods assessed in the past. We marked the shells of 30 adult Chinese mystery snails Bellamya chinensis and held them in an aquarium for 181 days. We observed no complete degradation of any enamel-paint mark during the 181 days. The enamel-paint mark was superior to a nai;-polish mark, which lasted a median of 100 days. Enamel-paint marks also have a lower rate of loss (0.00 month-1 181 days) than plastic bee tags (0.01 month-1, 57 days), gouache paint (0.07 month-1, 18.5 days), or car body paint from studies found in scientific literature. Legibility of enamel-paint marks had a median lifetime of 102 days. The use of enamel paint on the shells of gastropods is a viable option for studies lasting up to 6 months. Furthermore, visits to capture-mark-recapture site 1 year after application of enamel-paint marks on B. chinesnis shells produced several individuals on which the enamel paint was still visible, although further testing is required to clarify durability over longer periods.

  7. On denture marking.

    PubMed

    Borrman, H I; DiZinno, J A; Wasén, J; René, N

    1999-06-01

    During the last decades in Sweden dentures have been permanently marked with a stainless steel metal band incorporated into the acrylic and containing the patient's birth date, a special number, and "S" for Sweden. The last recommendation issued by the National Board of Health and Welfare states that "the patients shall always be offered denture marking and be informed about the benefit thereof. Denture marking is not permitted if the patient refuses it". Requirements for denture markers have been that they should be biologically inert (when incorporated into the denture), not be expensive, be easy to inscribe, be possible to retrieve after an accident, and survive elevated temperatures for a reasonable time under normal circumstances. Although the frequency of edentulousness has decreased in recent years due to the improvement in oral health there remains a need to address the issue of marking of complete dentures, because there is a large variation in the oral status of populations in different countries. Given that only one marked denture can reveal the identity of a deceased person when all other methods fail to do so, makes it worthwhile. Furthermore, denture marking is important in long-term care facilities. We have investigated the issue of denture marking in Europe and in the United States. The results from the European survey show that denture marking is, to our knowledge regulated by law only in Sweden and Iceland. In the US denture marking is so far mandatory in 21 states while New York State requires dentures to be marked if the patient requests it and several other states impose the obligation to mark dentures on long-term care facilities. Since there is no international consensus regarding the issue of denture marking it is important to address it. A survey from the Nordic countries has shown that if denture marking was in general use, the contribution to the establishment of identity by forensic odontology in cases of fire would increase by about 10

  8. A conscious rat model involving bradycardia and hypotension after oral administration: a toxicokinetical study of aconitine.

    PubMed

    Zhang, Panpan; Kong, Dezhi; Du, Qian; Zhao, Jing; Li, Qing; Zhang, Jianghua; Li, Tonghui; Ren, Leiming

    2017-06-01

    1. A model of aconitine-induced bradycardia and hypotension, which is similar to aconitine poisoning in humans, was constructed in conscious rats by oral administration. 2. Blood pressure (BP) and heart rate (HR) of Sprague-Dawley rats were measured using a volume pressure recording (VPR) system. The pharmacokinetics of toxic doses of aconitine and its metabolites were analyzed using UPLC-MS/MS. 3. The HR was significantly decreased by 29% at 2 h after oral administration of 200 μg/kg aconitine. When the dose was increased to 400 μg/kg, systolic BP and diastolic BP were significantly decreased by 11% and 12% at 2 h after the administration, except when bradycardia occurred at 2 h and 4 h. The drug concentration-time curve showed a double-peak phenomenon in rats administered a 400 μg/kg dose. The AUC 0-12 h value in the 400 μg/kg group significantly increased 0.8-fold compared to the 200 μg/kg group. Moreover, a high plasma concentration of 16-O-demethyaconitine was found in the rats that received two toxic doses. 4. In conclusion, bradycardia and hypotension are induced in conscious rats by a toxic dose of aconitine (400 μg/kg), and there was no significant difference in dose-normalized AUC 0-12 h values between oral administrations of 200 μg/kg and that of 400 μg/kg. However, the dose-normalized C max and AUC 0-12 h values in 200 μg/kg and 400 μg/kg groups were significantly smaller than those in 100 μg/kg group. The metabolites of aconitine, 16-O-demethyaconitine, and benzoylaconitine may also contribute to the hypotensive response.

  9. Spinal instrumentation for Duchenne's muscular dystrophy: experience of hypotensive anaesthesia to minimise blood loss.

    PubMed

    Fox, H J; Thomas, C H; Thompson, A G

    1997-01-01

    Nineteen patients with Duchenne's muscular dystrophy underwent segmental spinal instrumentation and posterior fusion between 1989 and 1994. The indication for surgery was loss of the ability to walk and development of scoliosis with sitting discomfort. Preoperative assessment included evaluation of pulmonary function. Average age at operation was 12.5 years. Instrumentation and fusion extended from upper thoracic levels to L-5 or the sacrum. A Hartshill rectangle was used in all cases, with banked allograft bone. Severe intraoperative blood loss was avoided by use of hypotensive anaesthesia. Peroperatively, systolic blood pressure was maintained between 75 and 85 mm Hg. Average blood loss was 1,246 ml (range, 400-3,100) or 30% of estimated total blood volume. Average transfusion requirements were 3 units of packed cells. Postoperative analgesia was provided by infusion via an epidural catheter. There were no postoperative wound or chest infections. Three patients required catheterisation for urinary retention. Postoperatively patients were fitted with a Neofract jacket to allow early mobilisation and discharge. Mean postoperative length of stay was 16 days. Posterior spinal fusion by using the Hartshill rectangle provided good correction and fixation. Hypotensive anaesthesia permitted surgery to be performed rapidly in a relatively dry field and avoided the complications of severe intraoperative blood loss and massive transfusion.

  10. Epidemiology, Diagnosis, and Management of Neurogenic Orthostatic Hypotension

    PubMed Central

    Palma, Jose-Alberto; Kaufmann, Horacio

    2017-01-01

    Background Orthostatic hypotension (OH) is a sustained fall in blood pressure on standing which can cause symptoms of organ hypoperfusion. OH is associated with increased morbidity and mortality and leads to a significant number of hospital admissions particularly in the elderly (233 per 100,000 patients over 75 years of age in the US). OH can be due to volume depletion, blood loss, large varicose veins, medications, or due to defective activation of sympathetic nerves and reduced norepinephrine release upon standing (i.e., neurogenic OH). Methods and Findings Literature review. Neurogenic OH is a frequent and disabling problem in patients with synucleinopathies such as Parkinson disease, multiple system atrophy, and pure autonomic failure, and is commonly associated with supine hypertension. Several pharmacological and non-pharmacological therapeutic options are available. Conclusions Here we review the epidemiology, diagnosis, and management of neurogenic OH, and provide an algorithm for its treatment emphasizing the importance of removing aggravating factors, implementing non-pharmacologic measures, and selecting appropriate pharmacological treatments. PMID:28713844

  11. Reversible Holmes' tremor due to spontaneous intracranial hypotension.

    PubMed

    Iyer, Rajesh Shankar; Wattamwar, Pandurang; Thomas, Bejoy

    2017-07-27

    Holmes' tremor is a low-frequency hand tremor and has varying amplitude at different phases of motion. It is usually unilateral and does not respond satisfactorily to drugs and thus considered irreversible. Structural lesions in the thalamus and brainstem or cerebellum are usually responsible for Holmes' tremor. We present a 23-year-old woman who presented with unilateral Holmes' tremor. She also had hypersomnolence and headache in the sitting posture. Her brain imaging showed brain sagging and deep brain swelling due to spontaneous intracranial hypotension (SIH). She was managed conservatively and had a total clinical and radiological recovery. The brain sagging with the consequent distortion of the midbrain and diencephalon was responsible for this clinical presentation. SIH may be considered as one of the reversible causes of Holmes' tremor. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  12. Hemodynamic and autonomic nervous system responses to mixed meal ingestion in healthy young and old subjects and dysautonomic patients with postprandial hypotension

    NASA Technical Reports Server (NTRS)

    Lipsitz, L. A.; Ryan, S. M.; Parker, J. A.; Freeman, R.; Wei, J. Y.; Goldberger, A. L.

    1993-01-01

    BACKGROUND. Although postprandial hypotension is a common cause of falls and syncope in elderly persons and in patients with autonomic insufficiency, the pathophysiology of this disorder remains unknown. METHODS AND RESULTS. We examined the hemodynamic, splanchnic blood pool, plasma norepinephrine (NE), and heart rate (HR) power spectra responses to a standardized 400-kcal mixed meal in 11 healthy young (age, 26 +/- 5 years) and nine healthy elderly (age, 80 +/- 5 years) subjects and 10 dysautonomic patients with symptomatic postprandial hypotension (age, 65 +/- 16 years). Cardiac and splanchnic blood pools were determined noninvasively by radionuclide scans, and forearm vascular resistance was determined using venous occlusion plethysmography. In healthy young and old subjects, splanchnic blood volume increased, but supine blood pressure remained unchanged after the meal. In both groups, HR increased and systemic vascular resistance remained stable. Forearm vascular resistance and cardiac index increased after the meal in elderly subjects, whereas these responses were highly variable and of smaller magnitude in the young. Young subjects demonstrated postprandial increases in low-frequency HR spectral power, representing cardiac sympatho-excitation, but plasma NE remained unchanged. In elderly subjects, plasma NE increased after the meal but without changes in the HR power spectrum. Patients with dysautonomia had a large postprandial decline in blood pressure associated with no change in forearm vascular resistance, a fall in systemic vascular resistance, and reduction in left ventricular end diastolic volume index. HR increased in these patients but without changes in plasma NE or the HR power spectrum. CONCLUSIONS. 1) In healthy elderly subjects, the maintenance of blood pressure homeostasis after food ingestion is associated with an increase in HR, forearm vascular resistance, cardiac index, and plasma NE. In both young and old, systemic vascular resistance is

  13. The effect of intraoperative hypotension on the outcomes of initial hybrid palliation for single ventricle congenital heart disease: an historical cohort study.

    PubMed

    Koziol, James; Gertler, Ralph; Manlhiot, Cedric; McCrindle, Brian; Holtby, Helen; Caldarone, Christopher A; Taylor, Katherine

    2013-05-01

    The "hybrid procedure" is an alternative surgical palliation strategy for single ventricle congenital heart disease. The purported benefit is improved cognitive ability secondary to avoidance of cardiopulmonary bypass in the neonatal period when neuronal apoptosis is greater. It is unknown whether survival is improved after this procedure. Intraoperative hypotension is common in these patients, and we hypothesized that this hypotension was associated with mortality or morbidity. We reviewed the records of 58/58 patients undergoing a first-stage hybrid procedure from 2004 to 2010 in a tertiary pediatric academic centre. Risk factors for poor outcome and the association between intraoperative hypotension and morbidity or mortality were investigated. Average preoperative arterial blood pressure (ABP) [systolic/diastolic presented as mean (standard deviation)] were 68 (12.7) / 38 (9.4) mmHg. Post-induction ABP was 65 (15.2) / 37 (8.6) mmHg. The average intraoperative nadir of ABP was 45 (7.0) / 26 (4.8) mmHg. On return to the intensive care unit (ICU), the average ABP was 69 (13.7) / 38 (11.6) mmHg. The nadir lasted longer than ten minutes in 32/58 patients. The mortality at 48 hr, 60 days, and 12 months was 3/58 (5%), 10/58 (17%), and 15/58 (26%), respectively. Six patients returned to the ICU on extracorporeal membrane oxygenation (ECMO). There was a weak statistical correlation between the average mean and diastolic BP pre-induction and changes of > 20% in systolic and diastolic BP during the case. In this patient cohort, we can show an association between short periods of intraoperative hypotension and mortality or return to the ICU on ECMO, but the importance of this is not certain.

  14. The efficacy of Labetalol versus Nitroglycerin for induction of controlled hypotension during sinus endoscopic surgery. A prospective, double-blind and randomized study.

    PubMed

    El-Shmaa, Nagat S; Ezz, Hoda Alsaid Ahmed; Younes, Ahmed

    2017-06-01

    To assess the efficacy of labetalol versus nitroglycerin for induction of controlled hypotension during sinus endoscopic surgery. A prospective, double-blind and randomized study. Carried out in operating room in university hospital. 60 patients of both sexes, American Society of Anesthesiologists (ASA) physical status I and II, age range from 20 to 60years; scheduled for elective sinus endoscopic surgery under general anesthesia (GA). Patients were divided into two groups (30 each). NTG group received nitroglycerin infusion at a dose of 2-5μg/kg/min, LAB group received labetalol infusion at a dose of 0.5-2mg/min. Surgical condition was assessed by surgeon using average category scale (ACS) of 0-5, a value of 2-3 being ideal. In both groups mean arterial blood pressure (MAP) was gradually reduced till the ideal ACS for assessment of surgical condition, the target of ACS was 2-3 or lower. Both studied drugs achieved desired hypotension and improved visualization of surgical field by decreasing bleeding in the surgical site, but ideal surgical conditions were created at mild hypotension (MAP 70-75) in LAB group while same conditions were created at MAP of 65-69mmHg in NTG group. Mean heart rate (HR) was significantly higher in NTG group as compared to LAB group. Blood loss decreased significantly in LAB group. Both labetalol and NTG are effective and safe drugs for induction of controlled hypotension during sinus endoscopic surgery. While, labetalol was better as it offered optimum operative condition with mild decrease in blood pressure, decreased surgical bleeding and less tachycardia during the surgery. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Effects of Hypotensive Anesthesia on Reducing Intraoperative Blood Loss, Duration of Operation, and Quality of Surgical Field During Orthognathic Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

    PubMed

    Lin, Susie; McKenna, Samuel J; Yao, Chuan-Fong; Chen, Yu-Ray; Chen, Chit

    2017-01-01

    The objective of this study was to evaluate the efficacy of hypotensive anesthesia in reducing intraoperative blood loss, decreasing operation time, and improving the quality of the surgical field during orthognathic surgery. A systematic review and meta-analysis of randomized controlled trials addressing these issues were carried out. An electronic database search was performed. The risk of bias was evaluated with the Jadad Scale and Delphi List. The inverse variance statistical method and a random-effects model were used. Ten randomized controlled trials were included for analysis. Our meta-analysis indicated that hypotensive anesthesia reduced intraoperative blood loss by a mean of about 169 mL. Hypotensive anesthesia was not shown to reduce the operation time for orthognathic surgery, but it did improve the quality of the surgical field. Subgroup analysis indicated that for blood loss in double-jaw surgery, the weighted mean difference favored the hypotensive group, with a reduction in blood loss of 175 mL, but no statistically significant reduction in blood loss was found for anterior maxillary osteotomy. If local anesthesia with epinephrine was used in conjunction with hypotensive anesthesia, the reduction in intraoperative blood loss was increased to 254.93 mL. Hypotensive anesthesia was effective in reducing blood loss and improving the quality of the surgical field, but it did not reduce the operation time for orthognathic surgery. The use of local anesthesia in conjunction with hypotensive general anesthesia further reduced the amount of intraoperative blood loss for orthognathic surgery. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Diuresis and reduced urinary osmolality in rats produced by small-molecule UT-A-selective urea transport inhibitors.

    PubMed

    Esteva-Font, Cristina; Cil, Onur; Phuan, Puay-Wah; Su, Tao; Lee, Sujin; Anderson, Marc O; Verkman, A S

    2014-09-01

    Urea transport (UT) proteins of the UT-A class are expressed in epithelial cells in kidney tubules, where they are required for the formation of a concentrated urine by countercurrent multiplication. Here, using a recently developed high-throughput assay to identify UT-A inhibitors, a screen of 50,000 synthetic small molecules identified UT-A inhibitors of aryl-thiazole, γ-sultambenzosulfonamide, aminocarbonitrile butene, and 4-isoxazolamide chemical classes. Structure-activity analysis identified compounds that inhibited UT-A selectively by a noncompetitive mechanism with IC50 down to ∼1 μM. Molecular modeling identified putative inhibitor binding sites on rat UT-A. To test compound efficacy in rats, formulations and administration procedures were established to give therapeutic inhibitor concentrations in blood and urine. We found that intravenous administration of an indole thiazole or a γ-sultambenzosulfonamide at 20 mg/kg increased urine output by 3-5-fold and reduced urine osmolality by ∼2-fold compared to vehicle control rats, even under conditions of maximum antidiuresis produced by 1-deamino-8-D-arginine vasopressin (DDAVP). The diuresis was reversible and showed urea > salt excretion. The results provide proof of concept for the diuretic action of UT-A-selective inhibitors. UT-A inhibitors are first in their class salt-sparing diuretics with potential clinical indications in volume-overload edemas and high-vasopressin-associated hyponatremias. © FASEB.

  17. Level of adherence to ocular hypotensive agents and its determinant factors among glaucoma patients in Menelik II Referral Hospital, Ethiopia.

    PubMed

    Mehari, Tesfay; Giorgis, Abeba T; Shibeshi, Workineh

    2016-08-02

    Good adherence to ocular hypotensive agents is important to control intraocular pressure and hence to prevent progressive glaucomatous optic nerve head damage. Periodic investigation of adherence is crucial in glaucoma treatment. The purpose of this study was to assess level of adherence to ocular hypotensive agents and to identify factors affecting adherence among glaucoma patients at a tertiary public eye care center. The study was a hospital-based cross-sectional study that was conducted in Menelik II Referral Hospital from June 1, 2015 to July 31, 2015. A systematic random sampling technique was used to select 359 study participants from the source population. The study patients were interviewed and their medical charts were reviewed using a pretested structured questionnaire. Adherence was assessed using Morisky Medication Adherence Scale - 8 and adherence determinant factors were identified using multivariate binary logistic regression analysis. The association was declared statistically significant at p < 0.05. Among the 359 study glaucoma patients, 42.6 % were adherent to their prescribed hypotensive agents. Higher educational level (AOR = 4.60, 95 % CI: 1.01-21.03, p < 0.049), being self - employed (AOR = 6.14, 95 % CI: 1.37-27.50, p < 0.018) and taking lesser frequency of drops (AOR = 2.89, 95 % CI: 1.25-6.66, p < 0.013) were significantly associated with adherence, whereas being a farmer (AOR = 0.07, 95 % CI: 0.01-0.75, p < 0.028), having very low monthly family income (AOR = 0.22, 95 % CI: 0.06-0.77, p < 0.019) and self - purchasing of medications (AOR = 0.30, 95 % CI: 0.10-0.93, p < 0.036) were significantly associated with non-adherence. The study has identified the adherence level to the prescribed ocular hypotensive agents to be sub-optimal and is influenced by different factors among glaucoma patients of the public tertiary center. We recommend glaucoma care providers to pay due attention

  18. Graded Compression Stockings Prevent Post-spaceflight Orthostatic Hypotension

    NASA Technical Reports Server (NTRS)

    Platts, S. H.; Brown, A. K.; Locke, J.; Stenger, M. B.

    2008-01-01

    Post-spaceflight orthostatic intolerance is characterized by hypotension and presyncope in 20-30% of returning astronauts. Previous data from our laboratory suggests that this is largely a result of decreased venous return. Currently, NASA astronauts wear an anti-gravity suit (AGS) which consists of inflatable air bladders over the calves, thighs and abdomen, which are typically pressurized from 0.5 to 1.5 PSI (27 to 78 mmHg). ISS crew members sometimes wear Russian Kentavr suits which consist of laced compression shorts and gaiters, providing 30 mmHg nominally. While these garments are effective during reentry, there are a number of drawbacks that make them impractical for postflight use. We studied the ability of commercially available, custom fit, graded compression stockings (Jobst, 55 mmHg at ankle to 6 mmHg at top of thigh, 25 mmHg mean compression) to prevent postflight orthostatic intolerance, hypothesizing that these garments would prevent orthostatic intolerance following short duration space flight. Crew members from a single Space Shuttle flight were tilted to 80 degrees for 10 min while wearing the stockings (n=5 males) upon arrival at the clinic (2 hrs after landing). Hemodynamic data were compared to data from all crewmembers tilted (without countermeasures) since return to flight (n=9). Two-way, repeated measures ANOVA, using the entire tilt time curve (0-10 min) show that systolic blood pressure (SBP, group effect p=0.008), stroke volume (SV, group effect p=0.003), and cardiac output (CO, group effect p=0.004) were higher in crewmembers who wore the Jobst stockings. A one-way ANOVA comparing the last minute standing also showed that SV (p=0.001) and CO (p less than 0.001) were higher and SBP tended to be higher (p=0.06) in Jobst subjects compared to controls. Control subjects had a higher rate of presyncope than Jobst subjects (3/9 vs 0/5) during the tilt on landing day. Orthostatic hypotension continues to present following spaceflight, despite

  19. Stretch marks

    MedlinePlus

    Stretch marks can appear when there is rapid stretching of the skin. The marks appear as parallel ... often disappear after the cause of the skin stretching is gone. Avoiding rapid weight gain helps reduce ...

  20. Neurogenic orthostatic hypotension in Parkinson's disease: evaluation, management, and emerging role of droxidopa.

    PubMed

    Isaacson, Stuart H; Skettini, Julia

    2014-01-01

    Neurogenic orthostatic hypotension (nOH) is due to failure of the autonomic nervous system to regulate blood pressure in response to postural changes due to an inadequate release of norepinephrine, leading to orthostatic hypotension and supine hypertension. nOH is common in Parkinson's disease (PD). Prevalence varies throughout the course of PD, ranging from 40% to 60%, and resulting in symptomatic nOH in approximately half. Symptomatic nOH, including lightheadedness, can limit daily activities and lead to falls. Symptomatic nOH can also limit therapeutic options for treating PD motor symptoms. Clinical evaluation should routinely include symptom assessment and blood pressure measurement of supine, sitting, and 3-minute standing; 24-hour ambulatory blood pressure monitoring can also be helpful. Non-pharmacological management of symptomatic nOH involves education, physical maneuvers, and adequate hydration. Current pharmacological treatment of symptomatic nOH includes salt supplement, fludrocortisone, midodrine, pyridostigmine, and other empiric medications. Despite these options, treatment of symptomatic nOH remains suboptimal, often limited by severe increases in supine blood pressure. Droxidopa, an oral prodrug converted by decarboxylation to norepinephrine, is a promising therapeutic option for symptomatic nOH in PD, improving symptoms of nOH, daily activities, falls, and standing systolic blood pressure in several recent trials. These trials demonstrated short-term efficacy and tolerability, with comparable increases in standing and supine blood pressures. Longer-term studies are ongoing to confirm durability of treatment effect.

  1. Semicarbazide-sensitive amine oxidase substrates potentiate hydralazine hypotension: possible role of hydrogen peroxide.

    PubMed

    Vidrio, Horacio; Medina, Martha; González-Romo, Pilar; Lorenzana-Jiménez, Marte; Díaz-Arista, Patricia; Baeza, Alejandro

    2003-11-01

    The relation between inhibition of semicarbazide-sensitive amine oxidase (SSAO) and vasodilation by hydralazine (HYD) was evaluated in chloralose/urethane-anesthetized rats pretreated with various substrates of the enzyme and subsequently administered a threshold hypotensive dose of the vasodilator. The SSAO substrates benzylamine, phenethylamine, and methylamine potentiate the hypotensive response to HYD. Methylamine, which was studied in greater detail because of its status as a possible endogenous SSAO substrate, does not influence the response to the reference vasodilator pinacidil; it does enhance HYD relaxation in aortic rings obtained from pretreated rats. Experiments designed to identify the product of SSAO activity responsible for potentiation by methylamine suggest involvement of hydrogen peroxide (H2O2), as evidenced by the findings that such potentiation is abolished by additional pretreatment with the H2O2-metabolizing enzyme catalase, and that the plasma concentration of H2O2 is increased by methylamine and decreased by HYD. These results are interpreted as a substantiation of the relation between the known SSAO inhibitory effect of HYD and its vasodilator activity. Pretreatment with the SSAO substrates would increase production of H2O2 in vascular smooth muscle and thus magnify the influence of this vasoconstrictor agent on vascular tone. In these conditions, the decrease in H2O2 production and hence in vascular tone caused by SSAO inhibition by HYD would also be magnified. It is speculated that inhibition of vascular SSAO could represent a novel mechanism of vasodilation.

  2. Androgenic-anabolic steroids inhibited post-exercise hypotension: a case control study.

    PubMed

    Junior, Jefferson F C R; Silva, Alexandre S; Cardoso, Glêbia A; Silvino, Valmir O; Martins, Maria C C; Santos, Marcos A P

    There is evidence of hypertensive effects caused by anabolic androgenic steroids (AAS). A single exercise session promotes the acute reduction of blood pressure, but the effects of AAS on this phenomenon are unknown. To investigate the post-exercise blood pressure response in androgenic-anabolic steroid users. Thirteen AAS users (23.9±4.3 years old) and sixteen controls (22.1±4.5 years old) performed a session of aerobic exercise. Heart rate and blood pressure were assessed before exercise and during a 60min post-exercise resting period. Repeated ANOVA measures were used to determine differences between the groups. While the control group had a significant reduction in post-exercise systolic blood pressure of up to 13.9±11.6mmHg at 40min, this phenomenon was limited among AAS users who reached a maximum of 6.2±11.5mmHg at 60min. The between groups comparison revealed significant higher post-exercise hypotension (PEH) for the control group at 30min (-12.9±14.1mmHg versus -2.9±7.6mmHg), 40min (-13.9±11.6mmHg versus -2.5±8.3mmHg), 50min (-13.9±13.9mmHg versus -5.0±7.9mmHg) and 60min (-12.5±12.8mmHg versus -6.2±11.5mmHg). There was no significant diastolic PEH in any of the groups. This study demonstrated impaired systolic post-exercise hypotension as a new adverse effect of AAS usage. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

  3. Involvement of nitric oxide in the mediation of the hypotensive action of the essential oil of Mentha x villosa in normotensive conscious rats.

    PubMed

    Lahlou, Saad; Magalhães, Pedro Jorge Caldas; Carneiro-Leão, Ricardo Ferreira Lima; Leal-Cardoso, José Henrique

    2002-08-01

    Recently, we showed that intravenous (i.v.) treatment with the essential oil of Mentha x villosa (EOMV) in pentobarbitone-anaesthetised rats decreased blood pressure; the effect occurred independently of the presence of an operational central autonomic drive to the cardiovascular system. This finding suggested that the hypotensive activity of EOMV may result from its vasodilatory effects directly upon vascular smooth muscle. The present study examines this possibility and whether EOMV-induced hypotension is mediated, at least in part, by an endothelial L-arginine/nitric oxide pathway. In conscious rats, i.v. injections of bolus doses (1 to 20 mg/kg) of EOMV elicited immediate and dose-dependent decreases in mean aortic pressure (MAP) and heart rate (HR). Pretreatment with i.v. hexamethonium (30 mg/kg) reduced the EOMV-induced bradycardia without affecting the hypotension. However, i.v. pretreatment with the nitric oxide synthase inhibitor, N(G)-nitro-L-arginine methyl (L-NAME, 20 mg/kg), reduced partially, but significantly, the maximal percent decreases in MAP elicited by EOMV without affecting the bradycardia. In rat isolated thoracic aorta preparations, EOMV (1 - 130 microg/ml) induced a concentration-dependent reduction of potassium (60 mM)-induced contraction. This smooth muscle-relaxant activity of EOMV was significantly reduced by the incubation of endothelium-intact rings with L-NAME (20 microM), as evidenced by the significant enhancement in the IC50 for EOMV-induced reduction of potassium-induced contraction (133.8 +/- 26.5 vs. 65.2 +/- 8.2 microg/ml in the absence of L-NAME). Furthermore, the vasorelaxant effects of EOMV in endothelium-denuded aortic rings were also significantly reduced (IC50 = 109 +/- 10 microg/ml), compared to those observed in segments with intact endothelium (IC50 = 61 +/- 13 microg/ml). These results show that i.v. treatment with EOMV dose-dependently decreases blood pressure in conscious rats, and that this action is due to an

  4. Stretch Marks

    MedlinePlus

    ... stretch marks. This isn't true with regular tanning or tanning beds , though: Stretch marks are less likely to ... up looking more obvious. Plus, the sun and tanning beds do more harm than good when it ...

  5. Effect of physical countermaneuvers on orthostatic hypotension in familial dysautonomia.

    PubMed

    Tutaj, Marcin; Marthol, Harald; Berlin, Dena; Brown, Clive M; Axelrod, Felicia B; Hilz, Max J

    2006-01-01

    Familial dysautonomia (FD) patients frequently experience debilitating orthostatic hypotension. Since physical countermaneuvers can increase blood pressure (BP) in other groups of patients with orthostatic hypotension, we evaluated the effectiveness of countermaneuvers in FD patients. In 17 FD patients (26.4 +/- 12.4 years, eight female), we monitored heart rate (HR), blood pressure (BP), cardiac output (CO), total peripheral resistance (TPR) and calf volume while supine, during standing and during application of four countermaneuvers: bending forward, squatting, leg crossing, and abdominal compression using an inflatable belt. Countermaneuvers were initiated after standing up,when systolic BP had fallen by 40mmHg or diastolic BP by 30mmHg or presyncope had occurred. During active standing, blood pressure and TPR decreased, calf volume increased but CO remained stable. Mean BP increased significantly during bending forward (by 20.0 (17 - 28.5) mmHg; P = 0.005) (median (25(th) - 75(th) quartile)), squatting (by 50.8 (33.5 - 56) mmHg; P = 0.002), and abdominal compression (by 5.8 (-1 - 34.7) mmHg; P = 0.04) - but not during leg-crossing. Squatting and abdominal compression also induced a significant increase in CO (by 18.1 (-1.3 - 47.9) % during squatting (P = 0.02) and by 7.6 (0.4 - 19.6) % during abdominal compression (P=0.014)). HR did not change significantly during the countermaneuvers. TPR increased significantly only during squatting (by 37.2 (11.8 - 48.2) %; P = 0.01). However, orthopedic problems or ataxia prevented several patients from performing some of the countermaneuvers. Additionally, many patients required assistance with the maneuvers. Squatting, bending forward and abdominal compression can improve orthostatic BP in FD patients, which is achieved mainly by an increased cardiac output. Squatting has the greatest effect on orthostatic blood pressure in FD patients. Suitability and effectiveness of a specific countermaneuver depends on the orthopedic

  6. [Headhache secondary to intracranial hypotension in a Lumbar Spinal Stenosis Surgery].

    PubMed

    Hidalgo-Mendía, Begoña; Angulo-Tabernero, Marina; Jaroid-Audes, Ricardo; Untoria-Agustín, Carmen; Rivero-Zelada, David

    2016-01-01

    Intracraneal hypotension headache is a well known syndrome in neurosurgery practice. In most cases cerebrospinal fluid leaks are caused by medical interventions, such as lumbar puncture, peridural anesthesia and surgical interventions on the spine. Clinical symptoms tipically show orthostatic headache that resolves in supine position, and other symptoms like neck tightness, vertigo and diplopia. RMI diagnostic confirms paquimeningeal enhancement and subdural hygromas. Conservative treatment usually includes bed resting, hydratation and administration of caffeine or glucocorticoids, resolving spontaneously in one to four months. The importance of the diagnosis lies in the differential diagnosis with other causes of headache, as symptomatic limiting factor in the rehabilitation of the patient and the same favorable prognosis.

  7. Neurogenic orthostatic hypotension - management update and role of droxidopa.

    PubMed

    Vijayan, Joy; Sharma, Vijay K

    2015-01-01

    Orthostatic hypotension (OH) is defined as a significant decrease in blood pressure (BP) during the first 3 minutes of standing or a head up on a tilt table. Symptoms of OH are highly variable, ranging from mild light-headedness to recurrent syncope. OH occurs due to dysfunction of one or more components of various complex mechanisms that interplay closely to maintain BP in a normal range during various physiological and associated disease states. Various biochemical and electrophysiological studies are often undertaken to assess the severity and etiology of OH. In addition to the lifestyle modifications, various medications that stimulate the adrenergic receptors or increase central blood volume are used in patients with OH. Droxidopa is a newer agent that increases the levels of norepinephrine in postganglionic sympathetic neurons. Management strategies for OH are presented, including the mechanism of action of droxidopa and various studies performed to assess its efficacy.

  8. Pavement markings and safety.

    DOT National Transportation Integrated Search

    2010-11-01

    Previous research on pavement markings from a safety perspective tackled various issues such as pavement marking retroreflectivity : variability, relationship between pavement marking retroreflectivity and driver visibility, or pavement marking impro...

  9. The effect of pre-donation hypotension on whole blood donor adverse reactions: a systematic review.

    PubMed

    Pauwels, Nele S; Cusack, Leila; De Buck, Emmy; Compernolle, Veerle; Vandekerckhove, Philippe

    2014-06-01

    Blood services are reliant upon healthy blood donors to provide a safe and adequate supply of blood products. Inappropriate variables contained within blood donor exclusion criteria can defer potentially appropriate donors. The aim of this systematic review was to examine the effect of low pre-donation blood pressure, as compared with normal blood pressure, on adverse events in allogeneic whole blood donors. A systematic review was performed using highly sensitive search strategies within five databases (Cochrane Central Register of Controlled Trials, CINAHL, Embase, MEDLINE, and Web of Science) from inception date until April 12, 2013. Out of 8305 records, 10 observational studies were identified that addressed the question. Five of these studies (with a combined total of 1,482,020 donations and 2903 donors) included either a statistical analysis or an appropriate study design that controlled for possible confounding factors. Based on the currently available evidence, hypotension has not been shown to be an independent predictive factor for donor complications. However, the overall quality of evidence was rather limited and rated 'low,' using the GRADE approach. In conclusion there is currently no evidence that hypotensive blood donors have a greater risk for donor adverse events compared with their normotensive counterparts. Copyright © 2014 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

  10. Hypotensive effects and angiotensin-converting enzyme inhibitory peptides of reishi (Ganoderma lingzhi) auto-digested extract.

    PubMed

    Tran, Hai-Bang; Yamamoto, Atsushi; Matsumoto, Sayaka; Ito, Hisatomi; Igami, Kentaro; Miyazaki, Toshitsugu; Kondo, Ryuichiro; Shimizu, Kuniyoshi

    2014-08-29

    Reishi (Ganoderma lingzhi) has been used as a traditional medicine for millennia. However, relatively little is known about this mushroom's proteins and their bioactivities. In this study, we used reishi's own proteases to hydrolyze its protein and obtained auto-digested reishi (ADR) extract. The extract was subjected to in vitro assays and administered to spontaneous hypertensive rats (SHRs) to determine its potential for use as a hypotensive medication. Bioassay-guided fractionation and de novo sequencing were used for identifying the active compounds. After 4 h administration of ADR, the systolic pressure of SHRs significantly decreased to 34.3 mmHg (19.5% change) and the effect was maintained up to 8 h of administration, with the decrease reaching as low as 26.8 mmHg (15% reduction-compare to base line a decrease of 26.8 mmHg is less than a decrease of 34.3 mmHg so it should give a smaller % reduction). Eleven peptides were identified and four of them showed potent inhibition against ACE with IC50 values ranging from 73.1 μM to 162.7 μM. The results showed that ADR could be a good source of hypotensive peptides that could be used for antihypertensive medication or incorporation into functional foods.

  11. Contribution of the leg vasculature to hypotensive effects of an antiorthostatic posture change in humans

    PubMed Central

    Pump, Bettina; Schou, Morten; Gabrielsen, Anders; Norsk, Peter

    1999-01-01

    Previous results from our laboratory have shown that vasodilatation in the legs prevents mean arterial pressure (MAP) from increasing during water immersion. Therefore, we tested the hypothesis that vasodilatation in the legs is necessary for the hypotensive effects to occur during a moderate antiorthostatic posture change. Ten healthy males underwent a 5 min posture change from upright seated to horizontal supine (SUP) and back to seated again with (OCCL-SUP) and without simultaneous total arterial (154 ± 1 mmHg) thigh occlusion, and a control seated period, also with and without arterial occlusion. Cardiac output (CO) was measured by a non-invasive foreign (N2O) gas rebreathing technique. MAP (brachial auscultation) decreased during SUP from 94 ± 3 to 84 ± 2 mmHg (P < 0.0001) and total peripheral vascular resistance (TPR = MAP/CO, n = 8) decreased by 15 ± 4 % (P < 0.001). During OCCL-SUP, MAP decreased from 98 ± 2 to 90 ± 2 mmHg (P < 0.005) and TPR decreased by 14 ± 3 % (P < 0.01). In conclusion, vasodilatation in the legs is not necessary for the decrease in MAP to occur during a moderate antiorthostatic manoeuvre. Therefore, vasodilatation in more central vascular beds (e.g. abdomen) can alone account for the hypotensive effects. PMID:10457077

  12. Evidence against bicarbonate reabsorption in the ascending limb, particularly as disclosed by free-water clearance studies.

    PubMed Central

    Seldin, D. W.; Rosin, J. M.; rector, F. C.

    1975-01-01

    Bicarbonate reabsorption in the thick ascending limb of Henle's loop was examined by studies of free-water clearance (CH2O) and free-water reabsorption (TcH2O). During maximal water diuresis in the dog, CH2O/GFR was taken as an indes of sodium reabsorption in, and urine flow (V/GFR) as an index of delivery of filtrate to, this scarbonate, infusion of a nonreabsorbable solute (hypotonic mannitol) and administration of an inhibitor of bicarbonate reabsorption (acetaent, but less than that achieved with hypotonic saline infusion. This suggests that sodium that sodium bicarbonate is not reabsorbed in the ascending limb. Rather, it is the sodium chloride, swept out of the proximal tubule by osmotic diuresis due to nonreabsorbed mannitol or sodium bicarbonate, that is reabsorbed in the ascending limb thereby increasing CH2O, whereas the nonreabsorption of mannitol and sodium bicarbonate results in a depressed CH20 per unit V when compared with hypotonic saline. V/GFR is not a satisfactory index of delivery to the ascending limb during osmotic diuresis, since it includes water obligated by nonreabsorbable solutes. When a better index of delivery, the sum of the clearances of chloride (CC1) and free-water (CH2O) is used, hypotonic bicarbonate infusion, hypotonic mannitol infusion and acetazolamide administration increase CH2O/GFR per unit delivery to the same extent as odes hypotonic saline infusion. Studies in dogs and rats on TcH2O also indicate that sodium bicarbonate is an impermeant solute in the ascending limb. Osmotic diuresis due to sodium bicarbonate diuresis, produced either by inhibition of sodium bicarbonate reabsorption (acetazolamide, L-lysine mono-hydrochloride) or infusion of sodium bicarbonate, or mannitol diuresis both produced marked chloruresis and increased TcH2O to the same extent as did hypertonic saline infusion. If chloride excretion was almost eliminated by hemodialysis against a chloride-free dialysate (dogs) or prolonged feeding of a salt

  13. L-dihydroxyphenylserine (Droxidopa) in the treatment of orthostatic hypotension: the European experience.

    PubMed

    Mathias, Christopher J

    2008-03-01

    Neurogenic orthostatic hypotension is a cardinal feature of generalised autonomic failure and commonly is the presenting sign in patients with primary autonomic failure. Orthostatic hypotension can result in considerable morbidity and even mortality and is a major management problem in disorders such as pure autonomic failure, multiple system atrophy and also in Parkinson's disease. Treatment is ideally two pronged, using non-pharmacological and pharmacological measures. Drug treatment ideally is aimed at restoring adequate amounts of the neurotransmitter noradrenaline. This often is not achievable because of damage to sympathetic nerve terminals, to autonomic ganglia or to central autonomic networks. An alternative is the use of sympathomimetics (that mimic the effects of noradrenaline, but are not identical to noradrenaline), in addition to other agents that target physiological mechanisms that contribute to blood pressure control.L-threo-dihydroxyphenyslerine (Droxidopa) is a pro-drug which has a structure similar to noradrenaline, but with a carboxyl group. It has no pressor effects in this form. It can be administered orally, unlike noradrenaline, and after absorption is converted by the enzyme dopa decarboxylase into noradrenaline thus increasing levels of the neurotransmitter which is identical to endogenous noradrenaline. Experience in Caucasians and in Europe is limited mainly to patients with dopamine beta hydroxylase deficiency. This review focuses on two studies performed in Europe, and provides information on its efficacy, tolerability and safety in patients with pure autonomic failure, multiple system atrophy and Parkinson's disease. It also addresses the issue of whether addition of dopa decarboxylase inhibitors, when combined with l-dopa in the treatment of the motor deficit in Parkinson's disease, impairs the pressor efficacy of Droxidopa.

  14. A diminished aortic-cardiac reflex during hypotension in aerobically fit young men

    NASA Technical Reports Server (NTRS)

    Shi, X.; Crandall, C. G.; Potts, J. T.; Williamson, J. W.; Foresman, B. H.; Raven, P. B.

    1993-01-01

    We compared the aortic-cardiac baroreflex sensitivity in eight average fit (AF: VO2max = 44.7 +/- 1.3 ml.kg-1 x min-1) and seven high fit (HF: VO2max = 64.1 +/- 1.7 ml.min-1 x kg-1) healthy young men during hypotension elicited by steady state sodium nitroprusside (SN) infusion. During SN mean arterial pressure (MAP) was similarly decreased in AF (-12.6 +/- 1.0 mm Hg) and HF (-12.1 +/- 1.1 mm Hg). However, the increases in heart rate (HR) were less (P < 0.023) in HF (15 +/- 3 bpm) than AF (25 +/- 1 bpm). When sustained neck suction (NS, -22 +/- 1 torr in AF and -20 +/- 1 torr in HF, P > 0.05) was applied to counteract the decreased carotid sinus transmural pressure during SN, thereby isolating the aortic baroreceptors, the increased HR remained less (P < 0.021) in HF (8 +/- 2 bpm) than AF (16 +/- 2 bpm). During both SN infusion and SN+NS, the calculated gains (i.e., delta HR/delta MAP) were significantly greater in AF (2.1 +/- 0.3 and 1.3 +/- 0.2 bpm.mm Hg-1) than HF (1.2 +/- 0.2 and 0.6 +/- 0.2 bpm.mm Hg-1). However, the estimated carotid-cardiac baroreflex sensitivity (i.e., the gain difference between the stage SN and SN + NS) was not different between AF (0.7 +/- 0.2 bpm.mm Hg-1) and HF (0.6 +/- 0.1 bpm.mm Hg-1). These data indicated that the aortic-cardiac baroreflex sensitivity during hypotension was significantly diminished with endurance exercise training.

  15. Hypotensive effect of alpha-lipoic acid after a single administration in rats.

    PubMed

    Dudek, Magdalena; Razny, Katarzyna; Bilska-Wilkosz, Anna; Iciek, Malgorzata; Sapa, Jacek; Wlodek, Lidia; Filipek, Barbara

    2016-05-01

    The effect of alpha-lipoic acid on blood pressure was investigated many times in chronic studies, but there are no studies on the effect of this compound after a single administration. Alpha-lipoic acid is a drug used in diabetic neuropathy, often in obese patients, to treat hypertension. Therefore, knowledge of the potential antihypertensive effect of alpha-lipoic acid even after a single dose and possibly too much pressure reduction is interesting and useful. The mechanism of the hypotensive effect of alpha-lipoic acid was examined in normotensive rats in vivo after a single intraperitoneal administration, blood pressure in the left carotid artery of the rats was measured prior to the administration of the compounds (alpha- lipoic acid and/or glibenclamide) and 80 min thereafter. Alpha-lipoic acid at a dosage of 50 mg/kg b.w. i.p. significantly decreased the blood pressure from the 50th min after drug administration. This cardiovascular effect of this compound was reversed by glibenclamide, a selective KATP blocker. Glibenclamide alone at this dose did not significantly affect the blood pressure. Statistical significance was evaluated using two-way ANOVA. This suggests that alpha-lipoic acid affects ATP-dependent potassium channels. It is possible that this is an indirect effect of hydrogen sulfide because alpha-lipoic acid can increase its concentration. The results obtained in this study are very important because the patients taking alpha-lipoic acid may be treated for co-existing hypertension. Therefore, the possibility of blood pressure lowering by alpha-lipoic acid should be taken into account, although it does not lead to excessive orthostatic hypotension.

  16. Prophylaxis against the systemic hypotension induced by propofol during rapid-sequence intubation.

    PubMed

    el-Beheiry, H; Kim, J; Milne, B; Seegobin, R

    1995-10-01

    The objective of this study was to determine the effectiveness of two prophylactic approaches against the anticipated hypotension induced by propofol during rapid-sequence intubation. Thirty-six male or female nonpremedicated ASA class I-II patients aged 21-60 yr undergoing elective outpatient surgery were included in the study. Patients were randomly allocated to receive pre-induction ephedrine sulphate (70 micrograms x kg(-1)iv), pre-induction volume loading (12 ml x kg(-1) Ringer's lactate) or no treatment. Rapid-sequence intubation with cricoid pressure was then performed with propofol (2.5 mg. x kg(-1)) and succinylcholine (1.5 mg x kg(-1). The lungs were subsequently ventilated with 0.25-0.5% isoflurane in a 2:1 N2O/O2 mixture. Vecuronium was given once neuromuscular function had recovered from the succinylcholine. Heart rate and systemic arterial blood pressure were measured non-invasively before induction, after propofol administration and every minute for ten minutes after intubation. Pre-induction volume loading prevented the hypotension observed before surgical stimulation in control and ephedrine groups. Moreover, pre-induction volume loading was not associated with increases in heart rate after intubation as was ephedrine administration. The intubating conditions were excellent to satisfactory in most patients and the overall incidence of adverse events during intubation was mainly due to pain during injection of propofol. The present study showed that preoperative volume loading is more efficacious than pre-induction administration of ephedrine sulphate in maintaining haemodynamic stability during rapid-sequence induction with propofol and succinylcholine. In addition, propofol in combination with succinylcholine provides excellent conditions for rapid-sequence intubation.

  17. Midodrine as a Countermeasure to Orthostatic Hypotension Immediately After Space Shuttle Landing

    NASA Technical Reports Server (NTRS)

    Platts, Steven H.; Stenger, Michael B.; Ribeiro, L. Christine; Lee, Stuart M. C.

    2010-01-01

    Midodrine prevents post-space flight orthostatic intolerance when testing is conducted in a controlled laboratory setting within 2-4 hours after Space Shuttle landing. It is unknown if midodrine is as effective during re-entry and immediately following landing. METHODS: Cardiovascular responses to 10 minutes of 80 head-up tilt in five male astronauts were compared before and immediately after Space Shuttle missions. Preflight tests were conducted in the Johnson Space Center Cardiovascular Laboratory without midodrine. Post-flight testing was performed in the Crew Transport Vehicle on the Space Shuttle runway within 60 minutes of landing; midodrine was self-administered before re-entry. Survival analysis was performed (Gehan-Breslow test) to compare presyncope rates pre- to post-flight. Cardiovascular responses (last minute standing minus supine) to tilt before and after space flight were compared using paired t-tests. RESULTS: Midodrine did not prevent post-flight orthostatic hypotension in two of the five astronauts, but the rate of presyncope across the group did not increase (p=0.17) from pre- to post-flight. Also, although the change in heart rate from supine to the last minute of standing was not affected by space flight, systolic blood pressure decreased more (p=0.05) and diastolic blood pressure tended to decrease (p=0.08) after space flight. CONCLUSIONS: Accurate interpretation of the current results requires that similar data be collected in control subjects (without midodrine) on the CTV. However, drug interaction concerns with commonly used anti-emetics and potentiation of prolonged QTc intervals observed in long duration astronauts make the routine use of midodrine for immediate post-flight orthostatic hypotension unlikely. 2

  18. Marking nut anaphylaxis

    PubMed Central

    Kral, Anita Christine; Hayball, John; Smith, William B

    2016-01-01

    Marking nut Semecarpus anacardium, so-called because it contains a pigment that has been used in the past to mark fabrics, is a known cause of contact hypersensitivity. It may be ingested as an ingredient of some traditional Hindi foods. We describe the first reported case of anaphylaxis to marking nut. PMID:27489793

  19. Mark Mehos | NREL

    Science.gov Websites

    Mehos Photo of Mark Mehos Mark Mehos Group Manager, Thermal Systems R&D Mark.Mehos@nrel.gov Thermal Systems R&D group at NREL, which includes the Concentrating Solar Power (CSP) Program. Since SolarPACES "Solar Thermal Electric Power Systems" task, which focuses on the development of

  20. Spontaneous Intracranial Hypotension: A Review and Introduction of an Algorithm For Management.

    PubMed

    Davidson, Benjamin; Nassiri, Farshad; Mansouri, Alireza; Badhiwala, Jetan H; Witiw, Christopher D; Shamji, Mohammed F; Peng, Philip W; Farb, Richard I; Bernstein, Mark

    2017-05-01

    Spontaneous intracranial hypotension (SIH) is a condition of low cerebrospinal fluid volume and pressure caused by a leak of cerebrospinal fluid through a dural defect. Diagnosis and management can be difficult, often requiring coordination between multiple disciplines for myelography, blood patching, and possible surgical repair. Patients should be monitored closely, because they can deteriorate into a coma or even death. There are no widely accepted guidelines for the management of SIH. We review the existing SIH literature, illustrate management challenges via a case review, and propose an algorithm developed by neurosurgeons, radiologists, and anesthesiologists intended to simplify and streamline the management of SIH. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Leaving A Mark: A Comparison Arthropod Protein Marking Protocols

    USDA-ARS?s Scientific Manuscript database

    Knowledge of arthropod pest and natural enemy disperal patterns is needed for effective and environmentally benign pest control. The most common tactics used to monitor arthropod dispersal patterns include mark-release-recapture (MRR) and mark-capture methodologies. Both methods require the applica...

  2. Mastering Marking Madness

    ERIC Educational Resources Information Center

    Moore, Brooke

    2009-01-01

    Teachers are smart people, so why does marking reduce them to stressed and soulless messes? Because in their hearts they know that students do not learn from it, and that drives them nuts. Researchers like Lorna Earl and Dylan Wiliam have looked closely at marking systems and have proven what teachers already know deep down: marking student work…

  3. Controlled hypotension for middle ear surgery: a comparison between remifentanil and magnesium sulphate.

    PubMed

    Ryu, J-H; Sohn, I-S; Do, S-H

    2009-10-01

    This prospective, randomized study was designed to compare remifentanil and magnesium sulphate during middle ear surgery in terms of postoperative pain and other complications. Eighty patients undergoing middle ear surgery were enrolled in the study. Patients were randomized into two groups of 40 to receive remifentanil (Group R) or magnesium sulphate (Group M) infusion. Propofol 2 mg kg(-1) was administered to induce anaesthesia, which was maintained using sevoflurane. Group R received a continuous infusion of remifentanil titrated between 3 and 4 ng ml(-1) using target-controlled infusion, whereas Group M received an i.v. magnesium sulphate bolus of 50 mg kg(-1) followed by a 15 mg kg(-1) h(-1) continuous infusion to maintain a mean arterial pressure (MAP) between 60 and 70 mm Hg. Haemodynamic variables, surgical conditions, postoperative pain, and adverse effects, such as postoperative nausea and vomiting (PONV) and shivering, were recorded. Controlled hypotension was well maintained in both groups. MAP and heart rate were higher in Group R than in Group M after operation. Surgical conditions were not different between the two groups. Postoperative pain scores were significantly lower in Group M than in Group R (P<0.05). Seventeen patients in Group R (43%) and seven patients in Group M (18%) developed PONV (P=0.01). Both magnesium sulphate and remifentanil when combined with sevoflurane provided adequate controlled hypotension and proper surgical conditions for middle ear surgery. However, patients administered magnesium sulphate had a more favourable postoperative course with better analgesia and less shivering and PONV.

  4. Comparison of surgical conditions in 2 different anesthesia techniques of esmolol-induced controlled hypotension in breast reduction surgery

    PubMed Central

    Besir, Ahmet; Cekic, Bahanur; Kutanis, Dilek; Akdogan, Ali; Livaoglu, Murat

    2017-01-01

    Abstract Background: Breast reduction surgery is a common cosmetic surgery with a high incidence of blood loss and transfusion. In this surgery, the reduction of blood loss related to surgical manipulation and the volume of resected tissue is a target. In the present study, we compared the effects of esmolol-induced controlled hypotension on surgical visibility, surgical bleeding, and the duration of surgery in patients anesthetized with propofol/remifentanil (PR) or sevoflurane/remifentanil (SR). Methods: Patients in the American Society of Anesthesiologists I/II risk group undergoing breast reduction surgery were prospectively randomized into PR (n = 25) and SR (n = 25) groups. Controlled hypotension was induced with esmolol in both groups. During the intraoperative period, the heart rate (HR), mean arterial pressure (MAP), operation duration, volume of intraoperative blood loss, volume of blood received through postoperative drains, volume of resected tissues, and surgical area bleeding score were recorded. Results: The duration of operation in the incisional period was shorter in group PR compared to group SR (P = 0.04). The change in HR was lower in incision and hemostasis periods in the group PR compared to the group SR (P < 0.001). Total intraoperative intraoperative bleeding volume and volume of blood received through drains on postoperative postoperative day 1, day 2, and in total were found to be significantly lower in group PR compared to group SR. Surgical visibility scoring was more effective in group PR compared to SR. Conclusion: In the breast reduction surgery performed under esmolol-induced controlled hypotension, the effect of propofol + remifentanil anesthesia on the duration of incisional surgery, surgical visibility, and volume of surgical blood loss was more reliable and effective compared to that of sevoflurane + remifentanil, which seems to be an advantage. PMID:28272228

  5. Sequential compression pump effect on hypotension due to spinal anesthesia for cesarean section: A double blind clinical trial.

    PubMed

    Zadeh, Fatemeh Javaherforoosh; Alqozat, Mostafa; Zadeh, Reza Akhond

    2017-05-01

    Spinal anesthesia (SA) is a standard technique for cesarean section. Hypotension presents an incident of 80-85% after SA in pregnant women. To determine the effect of intermittent pneumatic compression of lower limbs on declining spinal anesthesia induced hypotension during cesarean section. This double-blind clinical prospective study was conducted on 76 non-laboring parturient patients, aged 18-45 years, with the American Society of Anesthesiologist physical status I or II who were scheduled for elective cesarean section at Razi Hospital, Ahvaz, Iran from December 21, 2015 to January 20, 2016. Patients were divided into treatment mechanical pump (Group M) or control group (Group C) with simple random sampling. Fetal presentation, birth weight, Apgar at 1 and 5 min, time taken for pre-hydration (min), pre-hydration to the administration of spinal anesthesia (min), initiation of spinal to the delivery (min) and total volume of intravenous fluids, total dose of ephedrine and metoclopramide were recorded. Data were analyzed by SPSS version 19, using repeated measures of ANOVA and Chi square test. Heart rate, MPA, DAP and SAP changes were significantly higher in off-pump group in the baseline and 1st-minute (p<0.05), and in the other times, this change was significantly different with control groups. This research showed the suitability of the use of Sequential Compression Device (SCD) in reducing hypotension after spinal anesthesia for cesarean section, also this method can cause reducing vasopressor dosage for increased blood pressure, but the approval of its effectiveness requires repetition of the study with a larger sample size. The trial was registered at the Iranian Registry of Clinical Trials (http://www.irct.ir) with the IRCT ID: IRCT2015011217742N3. The authors received no financial support for the research, authorship, and/or publication of this article.

  6. Sequential compression pump effect on hypotension due to spinal anesthesia for cesarean section: A double blind clinical trial

    PubMed Central

    Zadeh, Fatemeh Javaherforoosh; Alqozat, Mostafa; Zadeh, Reza Akhond

    2017-01-01

    Background Spinal anesthesia (SA) is a standard technique for cesarean section. Hypotension presents an incident of 80–85% after SA in pregnant women. Objective To determine the effect of intermittent pneumatic compression of lower limbs on declining spinal anesthesia induced hypotension during cesarean section. Methods This double-blind clinical prospective study was conducted on 76 non-laboring parturient patients, aged 18–45 years, with the American Society of Anesthesiologist physical status I or II who were scheduled for elective cesarean section at Razi Hospital, Ahvaz, Iran from December 21, 2015 to January 20, 2016. Patients were divided into treatment mechanical pump (Group M) or control group (Group C) with simple random sampling. Fetal presentation, birth weight, Apgar at 1 and 5 min, time taken for pre-hydration (min), pre-hydration to the administration of spinal anesthesia (min), initiation of spinal to the delivery (min) and total volume of intravenous fluids, total dose of ephedrine and metoclopramide were recorded. Data were analyzed by SPSS version 19, using repeated measures of ANOVA and Chi square test. Results Heart rate, MPA, DAP and SAP changes were significantly higher in off-pump group in the baseline and 1st-minute (p<0.05), and in the other times, this change was significantly different with control groups. Conclusion This research showed the suitability of the use of Sequential Compression Device (SCD) in reducing hypotension after spinal anesthesia for cesarean section, also this method can cause reducing vasopressor dosage for increased blood pressure, but the approval of its effectiveness requires repetition of the study with a larger sample size. Trial registration The trial was registered at the Iranian Registry of Clinical Trials (http://www.irct.ir) with the IRCT ID: IRCT2015011217742N3. Funding The authors received no financial support for the research, authorship, and/or publication of this article. PMID:28713516

  7. Neurogenic orthostatic hypotension in Parkinson’s disease: evaluation, management, and emerging role of droxidopa

    PubMed Central

    Isaacson, Stuart H; Skettini, Julia

    2014-01-01

    Neurogenic orthostatic hypotension (nOH) is due to failure of the autonomic nervous system to regulate blood pressure in response to postural changes due to an inadequate release of norepinephrine, leading to orthostatic hypotension and supine hypertension. nOH is common in Parkinson’s disease (PD). Prevalence varies throughout the course of PD, ranging from 40% to 60%, and resulting in symptomatic nOH in approximately half. Symptomatic nOH, including lightheadedness, can limit daily activities and lead to falls. Symptomatic nOH can also limit therapeutic options for treating PD motor symptoms. Clinical evaluation should routinely include symptom assessment and blood pressure measurement of supine, sitting, and 3-minute standing; 24-hour ambulatory blood pressure monitoring can also be helpful. Non-pharmacological management of symptomatic nOH involves education, physical maneuvers, and adequate hydration. Current pharmacological treatment of symptomatic nOH includes salt supplement, fludrocortisone, midodrine, pyridostigmine, and other empiric medications. Despite these options, treatment of symptomatic nOH remains suboptimal, often limited by severe increases in supine blood pressure. Droxidopa, an oral prodrug converted by decarboxylation to norepinephrine, is a promising therapeutic option for symptomatic nOH in PD, improving symptoms of nOH, daily activities, falls, and standing systolic blood pressure in several recent trials. These trials demonstrated short-term efficacy and tolerability, with comparable increases in standing and supine blood pressures. Longer-term studies are ongoing to confirm durability of treatment effect. PMID:24729712

  8. Comparison of clinical efficacy among remifentanil, nicardipine, and remifentanil plus nicardipine continuous infusion for hypotensive anesthesia during arthroscopic shoulder surgery.

    PubMed

    Kim, Joon Yub; Song, Seong Hun; Cho, Jae Ho; Cho, Hyung Rae

    2017-01-01

    Hypotensive anesthesia is crucial during arthroscopic shoulder surgery to reduce bleeding and allow for clear visibility. The aim of this study was to compare the clinical efficacy of continuous infusion of remifentanil, nicardipine, and remifentanil plus nicardipine to control hypotensive anesthesia in arthroscopic shoulder surgery. For this study, we enrolled 45 consecutive patients who were scheduled to have arthroscopic rotator cuff repair surgery and randomly allocated them into remifentanil (group R, n = 15), nicardipine (group N, n = 15), and remifentanil plus nicardipine (group RN, n = 15) groups. During the surgeries, these drugs were administered with continuous infusion. We analyzed the mean arterial pressure (MAP) and heart rate during surgery, stay time in the recovery room, visual analogue scale (VAS) scores, use of antiemetics in the recovery room, and postoperative blood urea nitrogen and creatinine changes. The VAS score in the recovery room was higher for group R (mean 5.6, SD 1.4) than for groups N (mean 3.9, SD 0.9) and RN (mean 4.0, SD 1.1; p = 0.000). There were no statistical differences regarding other clinical variables among the three groups (all p > 0.05) except for MAP at 120 min of surgery between groups N and RN (N: 84.67 (SD 10.7) mmHg, RN: 65.4 (SD 9.2) mmHg, p = 0.027). The continuous infusion of remifentanil plus nicardipine appeared to be advantageous for maintaining hypotensive anesthesia until 120 min of arthroscopic shoulder surgery without rebound pain in a postanesthesia care unit.

  9. Effectiveness of droxidopa compared to midodrine in standing blood pressure and orthostatic tolerance in adults with neurogenic orthostatic hypotension: a systematic review protocol.

    PubMed

    Patrick, Kelli; Martin, Tina

    2017-09-01

    The question of this review is: what is the effectiveness of droxidopa compared to midodrine on standing blood pressure and orthostatic intolerance symptoms in adults with neurogenic orthostatic hypotension?

  10. [Indices of 24-hour monitoring of arterial blood pressure in patients with neurogenic syncope and patients with chronic constitution- dependent hypotension].

    PubMed

    Musaeva, Z A; Khapaev, B A; Fedotova, A V; Oknin, V Iu

    1999-01-01

    Clinical-psychologic study, spectral analysis of heart rate variability, 24-h monitoring of arterial pressure (AP) were performed in 20 patients with chronic constitutional arterial hypotension and in 18 patients with neurogenic syncopal states. Both groups were characterised by considerable manifestations of the syndrome of autonomic dystonia, by emotional-personal disorders that correlated with elevated level of slow-waves of the second order in heart rhythms' spectrum. That testified activation of supersegmental sympathetic-adrenal systems. Disorders in sympathetic-parasympathetic correlations were specific in each group. In patients with arterial hypotension disorder of circadian rhythm was observed in the form of superfluous decrease of diastolic AP during sleep. Circadian rhythms in patients with neurogenic syncopes have parameters characteristic for normals showing a preverved chronobiologic AP regulation. A role of the alterations revealed in pathogenesis of arterial hypotensionis discussed.

  11. Droxidopa for neurogenic orthostatic hypotension: a randomized, placebo-controlled, phase 3 trial.

    PubMed

    Kaufmann, Horacio; Freeman, Roy; Biaggioni, Italo; Low, Phillip; Pedder, Simon; Hewitt, L Arthur; Mauney, Joe; Feirtag, Michael; Mathias, Christopher J

    2014-07-22

    To determine whether droxidopa, an oral norepinephrine precursor, improves symptomatic neurogenic orthostatic hypotension (nOH). Patients with symptomatic nOH due to Parkinson disease, multiple system atrophy, pure autonomic failure, or nondiabetic autonomic neuropathy underwent open-label droxidopa dose optimization (100-600 mg 3 times daily), followed, in responders, by 7-day washout and then a 7-day double-blind trial of droxidopa vs placebo. Outcome measures included patient self-ratings on the Orthostatic Hypotension Questionnaire (OHQ), a validated, nOH-specific tool that assesses symptom severity and symptom impact on daily activities. From randomization to endpoint (n = 162), improvement in mean OHQ composite score favored droxidopa over placebo by 0.90 units (p = 0.003). Improvement in OHQ symptom subscore favored droxidopa by 0.73 units (p = 0.010), with maximum change in "dizziness/lightheadedness." Improvement in symptom-impact subscore favored droxidopa by 1.06 units (p = 0.003), with maximum change for "standing a long time." Mean standing systolic blood pressure (BP) increased by 11.2 vs 3.9 mm Hg (p < 0.001), and mean supine systolic BP by 7.6 vs 0.8 mm Hg (p < 0.001). At endpoint, supine systolic BP >180 mm Hg was observed in 4.9% of droxidopa and 2.5% of placebo recipients. Adverse events reported in ≥ 3% of double-blind droxidopa recipients were headache (7.4%) and dizziness (3.7%). No patients discontinued double-blind treatment because of adverse events. In patients with symptomatic nOH, droxidopa improved symptoms and symptom impact on daily activities, with an associated increase in standing systolic BP, and was generally well tolerated. This study provides Class I evidence that in patients with symptomatic nOH who respond to open-label droxidopa, droxidopa improves subjective and objective manifestation of nOH at 7 days. © 2014 American Academy of Neurology.

  12. Potent aquaretic agent. A novel nonpeptide selective vasopressin 2 antagonist (OPC-31260) in men.

    PubMed Central

    Ohnishi, A; Orita, Y; Okahara, R; Fujihara, H; Inoue, T; Yamamura, Y; Yabuuchi, Y; Tanaka, T

    1993-01-01

    Solute-free water diuretics (aquaretics) by antagonizing hydrosmotic vasopressin receptors (V2) may be useful in treating water-retaining diseases. The effects of intravenous administration of a newly developed nonpeptide, selective V2 antagonist, OPC-31260, at doses ranging from 0.017 to 1.0 mg/kg to groups of healthy, normally hydrated men were compared with those of 0.33 mg/kg furosemide and placebo. OPC-31260 increased the hypotonic urine volume dose dependently for the first 4 h, while furosemide induced sodium diuresis for 2 h. The absolute increase in the cumulative response in the urine to the highest doses of OPC-31260 was not significantly different from that to furosemide. The higher doses of OPC-31260 rapidly lowered urine osmolality for 2 h, particularly between minutes 15 and 45 (e.g., 1.0-mg/kg dose: 63 +/- 2 mOsm/kg in urine collected between minutes 30 and 45). In a marked hypotonic diuresis, mean free water clearance of the 4-h urine increased dose proportionally into the positive range, reaching 1.80 +/- 0.21 ml/min at 1.0 mg/kg. Whereas furosemide induced marked Na and K diuresis, OPC-31260 increased urinary Na excretion only slightly. At 4 h, 0.75 and 1.0 mg/kg of OPC-31260 almost doubled the plasma arginine vasopressin; and the higher doses increased plasma osmolality and plasma Na slightly, but did not alter plasma K, blood pressure, or heart rate. OPC-31260 thus safely induced a potent aquaretic effect in men. Images PMID:8254021

  13. Mark Tracking: Position/orientation measurements using 4-circle mark and its tracking experiments

    NASA Technical Reports Server (NTRS)

    Kanda, Shinji; Okabayashi, Keijyu; Maruyama, Tsugito; Uchiyama, Takashi

    1994-01-01

    Future space robots require position and orientation tracking with visual feedback control to track and capture floating objects and satellites. We developed a four-circle mark that is useful for this purpose. With this mark, four geometric center positions as feature points can be extracted from the mark by simple image processing. We also developed a position and orientation measurement method that uses the four feature points in our mark. The mark gave good enough image measurement accuracy to let space robots approach and contact objects. A visual feedback control system using this mark enabled a robot arm to track a target object accurately. The control system was able to tolerate a time delay of 2 seconds.

  14. Marking Time

    ERIC Educational Resources Information Center

    Foster, Colin

    2011-01-01

    Teachers say that they would gladly teach a day in the classroom if at the end of the day they could leave and have no marking. There is a common staffroom perception that mathematics teachers have it easy when it comes to marking. In arts subjects, setting an essay can be a fairly straightforward matter--a one-line question may suffice--but…

  15. Improving Marking Quality through a Taxonomy of Mark Schemes

    ERIC Educational Resources Information Center

    Ahmed, Ayesha; Pollitt, Alastair

    2011-01-01

    At the heart of most assessments lies a set of questions, and those who write them must achieve "two" things. Not only must they ensure that each question elicits the kind of performance that shows how "good" pupils are at the subject, but they must also ensure that each mark scheme gives more marks to those who are…

  16. Effects of water immersion on plasma catecholamines in normal humans

    NASA Technical Reports Server (NTRS)

    Epstein, M.; Johnson, G.; Denunzio, A. G.

    1983-01-01

    An investigation was conducted in order to determine whether water immersion to the neck (NI) alters plasma catecholamines in normal humans. Eight normal subjects were studied during a seated control study (C) and during 4 hr of NI, and the levels of norepinephrine (NE) and epinephrine (E) as determined by radioenzymatic assay were measured hourly. Results show that despite the induction of a marked natriuresis and diuresis indicating significant central hypervolemia, NI failed to alter plasma NE or E levels compared with those of either C or the corresponding prestudy 1.5 hr. In addition, the diuresis and natriuresis was found to vary independently of NE. These results indicate that the response of the sympathetic nervous system to acute volume alteration may differ from the reported response to chronic volume expansion.

  17. Neurogenic orthostatic hypotension – management update and role of droxidopa

    PubMed Central

    Vijayan, Joy; Sharma, Vijay K

    2015-01-01

    Orthostatic hypotension (OH) is defined as a significant decrease in blood pressure (BP) during the first 3 minutes of standing or a head up on a tilt table. Symptoms of OH are highly variable, ranging from mild light-headedness to recurrent syncope. OH occurs due to dysfunction of one or more components of various complex mechanisms that interplay closely to maintain BP in a normal range during various physiological and associated disease states. Various biochemical and electrophysiological studies are often undertaken to assess the severity and etiology of OH. In addition to the lifestyle modifications, various medications that stimulate the adrenergic receptors or increase central blood volume are used in patients with OH. Droxidopa is a newer agent that increases the levels of norepinephrine in postganglionic sympathetic neurons. Management strategies for OH are presented, including the mechanism of action of droxidopa and various studies performed to assess its efficacy. PMID:26089676

  18. Post-resistance exercise hypotension in spontaneously hypertensive rats is mediated by nitric oxide.

    PubMed

    Lizardo, J H F; Silveira, E A A; Vassallo, D V; Oliveira, E M

    2008-07-01

    1. Postexercise hypotension (PEH) plays an important role in the non-pharmacological treatment of hypertension. It is characterized by a decrease in blood pressure (BP) after a single bout of exercise in relation to pre-exercise levels. 2. The present study investigated the effect of a single session of resistance exercise, as well as the effect of nitric oxide (NO) and the autonomic nervous system (ANS), in PEH in spontaneously hypertensive rats (SHR). 3. Catheters were inserted into the left carotid artery and left jugular vein of male SHR (n = 37) for the purpose of measuring BP or heart rate (HR) and drug or vehicle administration, respectively. Haemodynamic measurements were made before and after acute resistance exercise. The roles of NO and the ANS were investigated by using N(G)-nitro-L-arginine methyl ester (L-NAME; 15 mg/kg, i.v.) and hexamethonium (20 mg/kg, i.v.) after a session of acute resistance exercise. 4. Acute resistance exercise promoted a pronounced reduction in systolic and diastolic BP (-37 +/- 1 and -8 +/- 1 mmHg, respectively; P < 0.05), which was suppressed after treatment with L-NAME. The reduction in systolic BP caused by exercise (-37 +/- 1 mmHg) was not altered by the administration of hexamethonium (-38 +/- 2 mmHg; P > 0.05). After exercise, the decrease in diastolic BP was greater with hexamethonium (-26 +/- 1 mmHg; P < 0.05) compared with the decrease caused by exercise alone. 5. The results suggest that acute resistance exercise has an important hypotensive effect on SHR and that NO plays a crucial role in this response.

  19. Elemental marking of arthropod pests in agricultural systems: single and multigenerational marking

    Treesearch

    Jane Leslie Hayes

    1991-01-01

    Use of elemental markers to study movement of arthropod pests of field crops is reviewed. Trace elements, rubidium (Rb) and cesium (Cs), have provided a nondisruptive method of marking natural adult populations via developmental stage consumption of treated host plants. Multigenerational marking occurs with the transfer of elemental markers from marked adults to...

  20. 14 CFR 45.10 - Marking.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Marking. 45.10 Section 45.10 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT IDENTIFICATION AND REGISTRATION MARKING Marking of Products and Articles § 45.10 Marking. No person may mark a product or article...

  1. 14 CFR 45.10 - Marking.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Marking. 45.10 Section 45.10 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT IDENTIFICATION AND REGISTRATION MARKING Marking of Products and Articles § 45.10 Marking. No person may mark a product or article...

  2. 14 CFR 45.10 - Marking.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Marking. 45.10 Section 45.10 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT IDENTIFICATION AND REGISTRATION MARKING Marking of Products and Articles § 45.10 Marking. No person may mark a product or article...

  3. 14 CFR 45.10 - Marking.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Marking. 45.10 Section 45.10 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT IDENTIFICATION AND REGISTRATION MARKING Marking of Products and Articles § 45.10 Marking. No person may mark a product or article...

  4. L-threo-dihydroxyphenylserine (L-threo-DOPS; droxidopa) in the management of neurogenic orthostatic hypotension: a multi-national, multi-center, dose-ranging study in multiple system atrophy and pure autonomic failure.

    PubMed

    Mathias, C J; Senard, J M; Braune, S; Watson, L; Aragishi, A; Keeling, J E; Taylor, M D

    2001-08-01

    This study was designed to determine the efficacy and tolerability of increasing doses of L-threo-dihydroxyphenylserine (L-threo-DOPS) in treating symptomatic orthostatic hypotension associated with multiple system atrophy (MSA) and pure autonomic failure (PAF). Following a one-week run-in, patients (26 MSA; 6 PAF) with symptomatic orthostatic hypotension received increasing doses of L-threo-DOPS (100, 200 and 300 mg, twice daily) in an open, dose-ranging study. Incremental dose adjustment (after weeks two and four of outpatient treatment) was based on clinical need until blood pressure (BP), and symptoms improved. Final dosage was maintained for six weeks. With L-threo-DOPS, systolic BP decrease was reduced during orthostatic challenge (-22+/-28 mm Hg reduction from a baseline decrease of 54.3+/-27.7 mm Hg, p = 0.0001, n = 32; supine systolic BP at final visit was 118.9+/-28.2 mm Hg). By the end of the study, 25 patients (78%) improved, and in 14 patients (44%) orthostatic hypotension was no longer observed. Decreased orthostatic systolic BP decrease occurred in 22% (7/32), 24% (6/25) and 61% (11/18) of patients treated with 100, 200, and 300 mg L-threo-DOPS twice daily, respectively. An improvement occurred in symptoms associated with orthostatic hypotension, such as light-headedness, dizziness (p = 0.0125), and blurred vision (p = 0.0290). L-threo-DOPS was well tolerated, with the 2 serious adverse events reported being a possible complication of the disease under study, and with no reports of supine hypertension. In conclusion, L-threo-DOPS (100, 200, and 300 mg, twice daily) was well tolerated. The dosage of 300 mg twice daily L-threo-DOPS seemed to offer the most effective control of symptomatic orthostatic hypotension in MSA and PAF.

  5. Effect of hypotensive therapy combined with modified diet or zinc supplementation on biochemical parameters and mineral status in hypertensive patients.

    PubMed

    Suliburska, Joanna; Skrypnik, Katarzyna; Szulińska, Monika; Kupsz, Justyna; Bogdański, Paweł

    2018-05-01

    Hypotensive therapy leads to a number of trace elements metabolism disturbances. Zinc balance is frequently affected by antihypertensive treatment. To evaluate the effect of a hypotensive treatment, modified diet and zinc supplementation on mineral status and selected biochemical parameters in newly diagnosed hypertensive patients on monotherapy. In the first stage, arterial hypertension in ninety-eight human subjects was diagnosed. In the second stage, antihypertensive monopharmacotherapy was implemented. In the third stage, patients were randomized into three groups and continued antihypertensive monotherapy: group D received an optimal-mineral-content diet, group S received zinc supplementation, and group C had no changes in diet or zinc supplementation. Iron, zinc, and copper concentrations in serum, erythrocytes, urine, and hair were determined. Lipids, glucose, ceruloplasmin, ferritin, albumin, C-reactive protein (CRP), tumor necrosis factor α (TNF-α), nitric oxide (NO), superoxide dismutase (SOD) and catalase (CAT) were assayed in serum. Antihypertensive monotherapy decreased zinc concentration in serum and erythrocytes and increased the level of zinc in urine, decreased CAT and SOD activity, TNF-α concentration in serum, and increased the level of NO in the serum. Zinc supply led to an increase in zinc concentration in serum, erythrocytes, and hair (in group S only). In the groups with higher zinc intake, decreased glucose concentration in the serum was observed. Significant correlation was seen between the zinc and glucose serum concentrations. Hypotensive drugs disturb zinc status in newly diagnosed hypertensive patients. Antihypertensive monotherapy combined with increased zinc supply in the diet or supplementation favorably modify zinc homeostasis and regulate glucose status without blood pressure affecting in patients with hypertension. Copyright © 2018 Elsevier GmbH. All rights reserved.

  6. Reversible coma and Duret hemorrhage after intracranial hypotension from remote lumbar spine surgery: case report.

    PubMed

    Bonow, Robert H; Bales, James W; Morton, Ryan P; Levitt, Michael R; Zhang, Fangyi

    2016-03-01

    Intracranial hypotension is a rare condition caused by spontaneous or iatrogenic CSF leaks that alter normal CSF dynamics. Symptoms range from mild headaches to transtentorial herniation, coma, and death. Duret hemorrhages have been reported to occur in some patients with this condition and are traditionally believed to be associated with a poor neurological outcome. A 73-year-old man with a remote history of spinal fusion presented with syncope and was found to have small subdural hematomas on head CT studies. He was managed nonoperatively and discharged with a Glasgow Coma Scale score of 15, only to return 3 days later with obtundation, fixed downward gaze, anisocoria, and absent cranial nerve reflexes. A CT scan showed Duret hemorrhages and subtle enlargement of the subdural hematomas, though the hematomas remained too small to account for his poor clinical condition. Magnetic resonance imaging of the spine revealed a large lumbar pseudomeningocele in the area of prior fusion. His condition dramatically improved when he was placed in the Trendelenburg position and underwent repair of the pseudomeningocele. He was kept flat for 7 days and was ultimately discharged in good condition. On long-term follow-up, his only identifiable deficit was diplopia due to an internuclear ophthalmoplegia. Intracranial hypotension is a rare condition that can cause profound morbidity, including tonsillar herniation and brainstem hemorrhage. With proper identification and treatment of the CSF leak, patients can make functional recoveries.

  7. Alkaloids in Erythrina by UPLC-ESI-MS and In Vivo Hypotensive Potential of Extractive Preparations

    PubMed Central

    Merlugo, Liara; Santos, Marí C.; Sant'Anna, Liane S.; Cordeiro, Everson W. F.; Batista, Luiz A. C.; Miotto, Silvia T. S.; Garcia, Cássia V.; Moreira, Cleci M.; Mendez, Andreas S. L.

    2015-01-01

    Erythrina species are used in popular medicine as sedative, anxiolytic, anti-inflammatory, and antihypertensive. In this work, we investigated the chemical composition of extracts obtained from leaves of E. falcata and E. crista-galli. The hypotensive potential of E. falcata and the mechanism of action were also studied. The extracts were obtained by maceration and infusion. The total content of phenolic compounds and flavonoids was estimated by spectrophotometric methods. The chemical constituents were studied performing a chromatographic analysis by UPLC-ESI-MS. For in vivo protocols, blood pressure and heart rate were measured by the invasive hemodynamic monitoring method. Different concentrations of extracts and drugs such as L-NAME, losartan, hexamethonium, and propranolol were administrated i.v. The results of total phenolic contents for E. falcata and E. crista-galli were 1.3193–1.4989 mgGAE/mL for maceration and 0.8771–0.9506 mgGAE/mL for infusion. In total flavonoids, the content was 7.7829–8.1976 mg RE/g for maceration and 9.3471–10.4765 RE mg/g for infusion. The chemical composition was based on alkaloids, suggesting the presence of erythristemine, 11β-methoxyglucoerysodine, erysothiopine, 11β-hydroxyerysodine-glucose, and 11-hydroxyerysotinone-rhamnoside. A potent dose-dependent hypotensive effect was observed for E. falcata, which may be related to the route of β-adrenergic receptors. PMID:26356581

  8. L-NAME, a nitric oxide synthase inhibitor, as a potential countermeasure to post-suspension hypotension in rats

    NASA Technical Reports Server (NTRS)

    Bayorh, M. A.; Socci, R. R.; Watts, S.; Wang, M.; Eatman, D.; Emmett, N.; Thierry-Palmer, M.

    2001-01-01

    A large number of astronauts returning from spaceflight experience orthostatic hypotension. This hypotension may be due to overproduction of vasodilatory mediators, such as nitric oxide (NO) and prostaglandins. To evaluate the role of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) as a countermeasure against the post-suspension reduction in mean arterial pressure (MAP), we assessed the cardiovascular responses and vascular reactivity to 7-day 30 degrees tail-suspension and a subsequent 6 hr post-suspension period in conscious rats. After a pre-suspension reading, direct MAP and heart rate (HR) were measured daily and every 2 hrs post-suspension. The NO synthase inhibitor L-NAME (20 mg/kg, i.v.), or saline, were administered after the 7th day reading prior to release from suspension and at 2 and 4 hrs post-suspension. At 6 hrs post-suspension, vascular reactivity was assessed. While MAP did not change during the suspension period, it was reduced post-suspension. Heart rate was not significantly altered. L-NAME administration reversed the post-suspension reduction in MAP. In addition, the baroreflex sensitivity for heart rate was modified by L-NAME. Thus, the post-suspension reduction in MAP may be due to overproduction of NO and altered baroreflex activity.

  9. Mark-recapture and mark-resight methods for estimating abundance with remote cameras: a carnivore case study

    USGS Publications Warehouse

    Alanso, Robert S.; McClintock, Brett T.; Lyren, Lisa M.; Boydston, Erin E.; Crooks, Kevin R.

    2015-01-01

    Abundance estimation of carnivore populations is difficult and has prompted the use of non-invasive detection methods, such as remotely-triggered cameras, to collect data. To analyze photo data, studies focusing on carnivores with unique pelage patterns have utilized a mark-recapture framework and studies of carnivores without unique pelage patterns have used a mark-resight framework. We compared mark-resight and mark-recapture estimation methods to estimate bobcat (Lynx rufus) population sizes, which motivated the development of a new "hybrid" mark-resight model as an alternative to traditional methods. We deployed a sampling grid of 30 cameras throughout the urban southern California study area. Additionally, we physically captured and marked a subset of the bobcat population with GPS telemetry collars. Since we could identify individual bobcats with photos of unique pelage patterns and a subset of the population was physically marked, we were able to use traditional mark-recapture and mark-resight methods, as well as the new “hybrid” mark-resight model we developed to estimate bobcat abundance. We recorded 109 bobcat photos during 4,669 camera nights and physically marked 27 bobcats with GPS telemetry collars. Abundance estimates produced by the traditional mark-recapture, traditional mark-resight, and “hybrid” mark-resight methods were similar, however precision differed depending on the models used. Traditional mark-recapture and mark-resight estimates were relatively imprecise with percent confidence interval lengths exceeding 100% of point estimates. Hybrid mark-resight models produced better precision with percent confidence intervals not exceeding 57%. The increased precision of the hybrid mark-resight method stems from utilizing the complete encounter histories of physically marked individuals (including those never detected by a camera trap) and the encounter histories of naturally marked individuals detected at camera traps. This new estimator

  10. Subdural hematoma caused by intracranial hypotension after syringosubarachnoid shunting--case report.

    PubMed

    Yamazaki, Tomosato; Yanaka, Kiyoyuki; Uemura, Kazuya; Tsukada, Atsuro

    2004-09-01

    A 32-year-old man developed an extremely rare subdural hematoma after syringosubarachnoid shunting for syringomyelia. He presented with a 4-year history of neck pain and spastic paraparesis resulting from T-7 and T-8 vertebral body fracture suffered in a traffic accident at age 22 years. Magnetic resonance imaging revealed syringomyelia between the craniocervical junction and the T-10 level. The symptoms were slowly progressive, and a syringosubarachnoid shunting was performed. His spasticity improved after surgery, but he developed orthostatic headache 7 days after surgery. Magnetic resonance imaging of the brain demonstrated a thin subdural hematoma over the right cerebral convexity. The subdural hematoma resolved spontaneously within a week with conservative treatment. Vigorous cerebrospinal fluid outflow observed during surgery presumably lowered the pressure in the syrinx cavity, leading to significant but transient intracranial hypotension and consequently the formation of subdural hematoma.

  11. Droxidopa for the short-term treatment of symptomatic neurogenic orthostatic hypotension in Parkinson's disease (nOH306B).

    PubMed

    Hauser, Robert A; Isaacson, Stuart; Lisk, Jerome P; Hewitt, L Arthur; Rowse, Gerry

    2015-04-15

    Neurogenic orthostatic hypotension (nOH) results from failure of norepinephrine responses to postural change to maintain standing systolic blood pressure (s-SBP). Droxidopa is an oral prodrug of norepinephrine. Study nOH306 enrolled patients with Parkinson's disease (PD) and symptomatic nOH. Subjects underwent up to 2 weeks of double-blind titration of droxidopa or placebo, followed by 8 weeks of double-blind maintenance treatment (100-600 mg thrice-daily). For the initial 51 subjects (study nOH306A, previously reported), the primary efficacy measure, Orthostatic Hypotension Questionnaire (OHQ) composite score, did not demonstrate significant change versus placebo at maintenance week 8. For the subsequent 171 subjects (study nOH306B, reported here), the primary efficacy measure was change versus placebo on item 1 ("dizziness, lightheadedness, feeling faint, or feeling like you might black out") of the Orthostatic Hypotension Symptom Assessment (OHSA) subsection of the OHQ at maintenance week 1. At week 1, mean (standard deviation) improvement on OHSA item 1 was 2.3 (2.95) for droxidopa versus 1.3 (3.16) for placebo (P = 0.018). In addition, mean increase in s-SBP at week 1 was 6.4 (18.85) for droxidopa versus 0.7 (20.18) mmHg for placebo (nominal P value: 0.032). Differences in change in OHSA item 1 scores from baseline to maintenance weeks 2, 4, and 8 were not statistically significant. Adverse-event (AE) incidence was similar across groups, but 12.4% of droxidopa and 6.1% of placebo subjects withdrew because of AEs. The most common AEs on droxidopa (vs. placebo) were headache (13.5% vs. 7.3%) and dizziness (10.1% vs. 4.9%). Study nOH306B demonstrated subjective (OHSA item 1) and objective (s-SBP) evidence of short-term droxidopa efficacy (vs. placebo) for symptomatic nOH in PD. © 2014 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

  12. Lujan Mark-4

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mocko, Michael Jeffrey; Zavorka, Lukas; Koehler, Paul E.

    2017-11-13

    This is a review of Mark-IV target neutronics design. It involved the major redesign of the upper tier, offering harder neutron spectra for upper-tier FPs; a redesign of the high-resolution (HR) moderator; and a preservation of the rest of Mark-III features.

  13. Minimal Marking: A Success Story

    ERIC Educational Resources Information Center

    McNeilly, Anne

    2014-01-01

    The minimal-marking project conducted in Ryerson's School of Journalism throughout 2012 and early 2013 resulted in significantly higher grammar scores in two first-year classes of minimally marked university students when compared to two traditionally marked classes. The "minimal-marking" concept (Haswell, 1983), which requires…

  14. 14 CFR 45.10 - Marking.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Marking. 45.10 Section 45.10 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT IDENTIFICATION AND REGISTRATION MARKING Identification of Aircraft and Related Products § 45.10 Marking. No person may mark a...

  15. A randomized trial of Korodin Herz-Kreislauf-Tropfen as add-on treatment in older patients with orthostatic hypotension.

    PubMed

    Kroll, M; Ring, C; Gaus, W; Hempel, B

    2005-06-01

    In a randomized, double-blind, placebo-controlled, parallel group, phase III clinical trial efficacy and safety of Korodin, a combination of natural D-camphor and an extract from fresh crataegus berries, was investigated in patients 50 years and older with orthostatic hypotension. At visit 1 eligibility of patients was checked and a placebo medication was given to all patients. At visit 2 orthostatic hypotension had to be reconfirmed, then the patient was randomized either to Korodin or placebo, study medication (25 drops) was applied once and then outcome was measured. After 7 days of home treatment with daily 3 x 25 drops outcome was measured at visit 3. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were documented 10, 5, 2 and 0 min before as well as 1, 3, 5, 8, and 10 min after getting in the upright position at visit 1, at visit 2 before and after application of study medication and at visit 3. Primary outcome was the change of mean arterial blood pressure (MAP) from just before standing up to the nadir within the first 3 min after standing up. Secondary outcome variables were SBP, DBP, HR, quality of life (SF-12) and seven typical signs and symptoms of orthostatic hypotension. The study was performed in a rehabilitation clinic and in two doctor's practices in Germany from November 2002 to May 2003. During this time, 57 patients were admitted to the study, 39 patients were eligible and randomized, 38 patients were treated according to protocol and evaluated, 21 patients with Korodin and 17 patients with placebo. After a single application the median decrease of MAP was 11.4 mmHg for Korodin and 14.0 mmHg for placebo. Compared to baseline, the median MAP improved 4.3 mmHg for Korodin and 0.3 mmHg for placebo. After 1 week of treatment the decrease of median MAP after standing up was 9.3 mmHg for Korodin and 13.3 mmHg for placebo. Compared to baseline, the improvement was 5.9 mmHg for Korodin and 1.6 mmHg for placebo. Efficacy

  16. Laser marking as environment technology

    NASA Astrophysics Data System (ADS)

    Sobotova, Lydia; Badida, Miroslav

    2017-11-01

    The contribution deals with the laser marking as one of the progressive and environment friendly technologies with utilisation in many branches of industry. Engraving and other types of laser marking of different types of materials are very actual technologies these days. Laser marking decreases the waste creation in comparison with the other classical marking technologies, which use paintings or created chips. In this experimental investigation the laser marking surface texturing of material AL99,7 according to STN 42 4003:1993-08 (STN EN 573) has been conducted. The laser marking machine TruMark 6020 and software TruTops Mark were used. Laser surface texturing after laser marking has been realised under different combinations of process parameters: pulse frequency, pulse energy and laser beam scanning speed. The morphological characterization of engraving or annealing surfaces has been performed using scanning electron microscopy (SEM) technique. The evaluation of roughness of engraved surfaces has been realized according to STN EN ISO 4287 by using Surftest SJ 301. The aim of the contribution was to show how different laser parameters affect the surface texture and colour change of metallic materials while creating minimal waste.

  17. The clinical effectiveness of permissive hypotension in blunt abdominal trauma with hemorrhagic shock but without head or spine injuries or burns: a systematic review

    PubMed Central

    Alsawadi, Abdulrahman

    2012-01-01

    Background Trauma is a major cause of death and disability. The current trend in trauma management is the rapid administration of fluid as per the Advanced Trauma Life Support guidelines, although there is no evidence to support this and even some to suggest it might be harmful. Some guidelines, protocols, and recommendations have been established for the use of permissive hypotension although there is reluctance concerning its application in blunt injuries. Objectives The aim of this review is to determine whether there is evidence of the use of permissive hypotension in the management of hemorrhagic shock in blunt trauma patients. This review also aims to search for any reason for the reluctance to apply permissive hypotension in blunt injuries. Methods This systematic review has followed the steps recommended in the Cochrane Handbook for Systematic Reviews of Interventions. It is also being reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement and checklist. Database searches of MEDLINE, EMBASE, the Centre for Reviews and Dissemination databases and the Cochrane Library were made for eligible studies as well as journal searches. Inclusion criteria included systematic reviews that have similar primary questions to this review and randomized controlled trials where patients with blunt torso injuries and hemorrhagic shock were not excluded. Rapid or early fluid administration was compared with controlled or delayed fluid resuscitation and a significant outcome was obtained. Results No systematic reviews attempting to answer similar questions were found. Two randomized controlled trials with mixed types of injuries in the included patients found no significant difference between the groups used in each study. Data concerning the question of this review was sought after these papers were appraised. Conclusion The limited available data are not conclusive. However, the supportive theoretical concept and laboratory

  18. Anxiety can significantly explain bolus perception in the context of hypotensive esophageal motility: Results of a large multicenter study in asymptomatic individuals.

    PubMed

    Cisternas, D; Scheerens, C; Omari, T; Monrroy, H; Hani, A; Leguizamo, A; Bilder, C; Ditaranto, A; Ruiz de León, A; Pérez de la Serna, J; Valdovinos, M A; Coello, R; Abrahao, L; Remes-Troche, J; Meixueiro, A; Zavala, M A; Marin, I; Serra, J

    2017-09-01

    Previous studies have not been able to correlate manometry findings with bolus perception. The aim of this study was to evaluate correlation of different variables, including traditional manometric variables (at diagnostic and extreme thresholds), esophageal shortening, bolus transit, automated impedance manometry (AIM) metrics and mood with bolus passage perception in a large cohort of asymptomatic individuals. High resolution manometry (HRM) was performed in healthy individuals from nine centers. Perception was evaluated using a 5-point Likert scale. Anxiety was evaluated using Hospitalized Anxiety and Depression scale (HAD). Subgroup analysis was also performed classifying studies into normal, hypotensive, vigorous, and obstructive patterns. One hundred fifteen studies were analyzed (69 using HRM and 46 using high resolution impedance manometry (HRIM); 3.5% swallows in 9.6% of volunteers were perceived. There was no correlation of any of the traditional HRM variables, esophageal shortening, AIM metrics nor bolus transit with perception scores. There was no HRM variable showing difference in perception when comparing normal vs extreme values (percentile 1 or 99). Anxiety but not depression was correlated with perception. Among hypotensive pattern, anxiety was a strong predictor of variance in perception (R 2 up to .70). Bolus perception is less common than abnormal motility among healthy individuals. Neither esophageal motor function nor bolus dynamics evaluated with several techniques seems to explain differences in bolus perception. Different mechanisms seem to be relevant in different manometric patterns. Anxiety is a significant predictor of bolus perception in the context of hypotensive motility. © 2017 John Wiley & Sons Ltd.

  19. TIA, stroke and orthostatic hypotension: a disease spectrum related to ageing vasculature?

    PubMed

    Kwok, C S; Ong, A C L; Potter, J F; Metcalf, A K; Myint, P K

    2014-06-01

    We sought to identify the determinants of orthostatic hypotension (OH) among patients referred to the transient ischaemic attack (TIA) clinic. We conducted a retrospective analysis of prospectively collected data on patients who attended the TIA clinic in a UK hospital between January 2006 and September 2009. Each patient had their supine and standing or sitting blood pressure measured. Logistic regression was used to estimate the univariate and multivariate odds of OH for the subgroups of patients based on their diagnosis. A 10% significance level for the univariate analysis was used to identify variables in the multivariate model. A total of 3222 patients were studied of whom 1131 had a TIA, 665 a stroke and 1426 had other diagnoses. The prevalence of either systolic or diastolic OH in the TIA, stroke and patients with other diagnoses was similar being 22% (n = 251), 24% (n = 162) and 20% (n = 292), respectively. Multivariate analyses showed age, prior history of TIA, and diabetes were independently significantly associated with systolic OH alone or diastolic OH alone or either systolic or diastolic OH [ORs 1.03 (1.02-1.05); 1.56 (1.05-2.31); 1.65 (1.10-2.47), respectively]. Among the patients with the diagnosis of stroke, peripheral vascular disease (PVD) was significantly associated with increased odds of OH (3.56, 1.53-8.31), whereas male gender had a significantly lower odds of OH (0.61, 0.42-0.88). In patients with other diagnoses, age (1.04, 1.02-1.05) and diabetes (1.47, 1.04-2.09) were associated with OH, whereas male gender was (0.76, 0.58-1.00) not associated with OH. Orthostatic hypotension is prevalent among patients presenting to TIA clinic. Previous history of vascular disease (prior TIA/stroke/PVD) appears to be a significant associate of OH in this patient population. © 2014 John Wiley & Sons Ltd.

  20. Time-dependent interactions of the hypotensive effects of sildenafil citrate and sublingual glyceryl trinitrate

    PubMed Central

    Oliver, James J; Kerr, Debra M; Webb, David J

    2009-01-01

    AIM To investigate the time course of the hypotensive interaction between sildenafil and glyceryl trinitrate (GTN). METHODS Two double-blind, placebo-controlled, randomized, crossover studies were performed. Subjects were challenged with sublingual GTN 400 µg at different times after oral sildenafil 100 mg. After each GTN challenge frequent measures of blood pressure (BP) were made. In the first study GTN was given 1–48 h after sildenafil/placebo to 33 healthy men. In the second study GTN was given 1–8 h after sildenafil/placebo to 20 men with stable angina. RESULTS In healthy men there was a greater mean maximum reduction in BP with sildenafil/GTN than with placebo/GTN only at 1 h. In angina patients, there was a greater mean maximum reduction in BP with sildenafil/GTN than with placebo/GTN for up to 8 h. The mean (95% confidence interval) differences in maximum systolic BP reduction (mmHg) at 1, 4, 6 and 8 h were −16 (−12, −21), −12 (−4, −20), −6 (1, −12) and −9 (−3, −15), all P < 0.05 except at 6 h (NS). At 6 and 8 h the interaction was not more than additive, and hypotensive symptoms did not occur. CONCLUSIONS In men with angina there is an interaction on BP reduction between sildenafil and GTN for ≥ 8 h after sildenafil administration, but this is no more than additive from 6 h. These data may be helpful to clinicians who are considering the use of GTN in patients presenting with angina who have received sildenafil within 24 h. PMID:19371313

  1. The association between orthostatic hypotension, falling and successful rehabilitation in a nursing home population.

    PubMed

    Hartog, L C; Cizmar-Sweelssen, M; Knipscheer, A; Groenier, K H; Kleefstra, N; Bilo, H J G; van Hateren, K J J

    2015-01-01

    Our objectives were to identify the prevalence of orthostatic hypotension (OH) in frail, elderly nursing home residents, and assess its possible association with falling and chances of successful rehabilitation. A prospective observational cohort study. A total of 290 patients participated in this study, of which 128 were admitted to the rehabilitation department. OH was defined as a drop in systolic blood pressure of >20mmHg and diastolic blood pressure of >10mmHg after postural change within 3min. The analyses regarding falling and successful rehabilitation were only performed in the rehabilitation group. Multivariate binary logistic regression analyses were used to describe risk factors related with falling. Cox proportional hazard modeling was used to investigate the relation between OH and the time to successful rehabilitation. The prevalence of OH in the studied nursing home population was 36.6% (95% CI (confidence interval): 31.1-42.1%). The prevalence varied from 28.6% (95% CI: 16.8-40.4%) in somatic patients, 36.7% (95% CI: 28.4-45.1%) in rehabilitation patients, to 40.6% (95% CI: 31.3-50.0%) in psychogeriatric patients. The association between orthostatic hypotension and previous falling was not significant; Odds ratio 0.66 (95% CI: 0.30-1.48). The Hazard ratio of the relationship between OH and successful rehabilitation was 2.88 (95% CI:1.77-4.69). OH is highly prevalent in nursing home residents. Surprisingly, patients with OH were found to have a higher chance of successful rehabilitation compared to patients without OH. If confirmed in other studies, these results may change our view of the implications of OH. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Norepinephrine precursor therapy in neurogenic orthostatic hypotension.

    PubMed

    Kaufmann, Horacio; Saadia, Daniela; Voustianiouk, Andrei; Goldstein, David S; Holmes, Courtney; Yahr, Melvin D; Nardin, Rachel; Freeman, Roy

    2003-08-12

    In patients with neurogenic orthostatic hypotension (NOH), the availability of the sympathetic neurotransmitter norepinephrine (NE) in the synaptic cleft is insufficient to maintain blood pressure while in the standing posture. We determined the effect of oral administration of the synthetic amino acid L-threo-3,4-dihydroxyphenylserine (L-DOPS), which is decarboxylated to NE by the enzyme L-aromatic amino acid decarboxylase (L-AADC) in neural and nonneural tissue, on blood pressure and orthostatic tolerance in 19 patients with severe NOH (8 with pure autonomic failure and 11 with multiple-system atrophy). A single-blind dose-titration study determined the most appropriate dose for each patient. Patients were then enrolled in a double-blind, placebo-controlled, crossover trial. L-DOPS significantly raised mean blood pressure both supine (from 101+/-4 to 141+/-5 mm Hg) and standing (from 60+/-4 to 100+/-6 mm Hg) for several hours and improved orthostatic tolerance in all patients. After L-DOPS, blood pressure increases were closely associated with increases in plasma NE levels. Oral administration of carbidopa, which inhibits L-AADC outside the blood-brain barrier, blunted both the increase in plasma NE and the pressor response to L-DOPS in all patients Acute administration of L-DOPS increases blood pressure and improves orthostatic tolerance in patients with NOH. The pressor effect results from conversion of L-DOPS to NE outside the central nervous system.

  3. Marking as Judgment

    ERIC Educational Resources Information Center

    Brooks, Val

    2012-01-01

    An aspect of assessment which has received little attention compared with perennial concerns, such as standards or reliability, is the role of judgment in marking. This paper explores marking as an act of judgment, paying particular attention to the nature of judgment and the processes involved. It brings together studies which have explored…

  4. Involvement of arginine-vasopressin in the diuretic and hypotensive effects of Pereskia grandifolia Haw. (Cactaceae).

    PubMed

    Kazama, Caroline Calixto; Uchida, Denise Thiemi; Canzi, Karina Natally; de Souza, Priscila; Crestani, Sandra; Gasparotto, Arquimedes; Laverde, Antonio

    2012-10-31

    Pereskia grandifolia Haw. (Cactaceae), popularly known as "ora-pro-nobis" is well recognized in Brazilian traditional medicine as a diuretic agent, although no scientific data have been published to support this effect. The aim of this work is to evaluate the diuretic and hypotensive activities of the infusion (INFPG) and the ethanol extract (HEPG) of Pereskia grandifolia and possible mechanism of action. The infusions (2.5-10%) and the HEPG (3-100 mg/kg) were orally administered in a single dose or daily (for seven days) to rats. The urine excretion rate, pH, density, conductivity and content of Na(+), K(+), Cl(-) and HCO(3)(-) were measured in the urine of saline-loaded animals. In collected serum samples the concentration of electrolytes, urea, creatinine, aldosterone, vasopressin and angiotensin converting enzyme (ACE) activity were evaluated. The involvement of V(2) vasopressin receptor in the diuretic activity and the hypotensive effect of HEPG were also determined. Water excretion rate was significantly increased by HEPG, while the urinary K(+) and Cl(-) excretion was significantly reduced in acute and prolonged treatment. The oral administration of the HEPG (30mg/kg) significantly reduced serum levels of vasopressin and the mean arterial pressure (MAP) in normotensive rats. All other evaluated parameters have not been affected by any treatment. The results showed that HEPG could present compound(s) responsible for aquaretic activities with no signs of toxicity, and this effect could involve a reduction in the arginine-vasopressin release. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  5. 9 CFR 316.9 - Products to be marked with official marks.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... marks. 316.9 Section 316.9 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... liver, beef tongue, and beef heart which has been inspected and passed shall be marked with the official... round, flank, loin, rib, plate, brisket, chuck, and shank are primal parts of beef carcasses. Veal...

  6. 9 CFR 316.9 - Products to be marked with official marks.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... marks. 316.9 Section 316.9 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... liver, beef tongue, and beef heart which has been inspected and passed shall be marked with the official... round, flank, loin, rib, plate, brisket, chuck, and shank are primal parts of beef carcasses. Veal...

  7. 9 CFR 316.9 - Products to be marked with official marks.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... marks. 316.9 Section 316.9 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... liver, beef tongue, and beef heart which has been inspected and passed shall be marked with the official... round, flank, loin, rib, plate, brisket, chuck, and shank are primal parts of beef carcasses. Veal...

  8. 9 CFR 316.9 - Products to be marked with official marks.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... marks. 316.9 Section 316.9 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... liver, beef tongue, and beef heart which has been inspected and passed shall be marked with the official... round, flank, loin, rib, plate, brisket, chuck, and shank are primal parts of beef carcasses. Veal...

  9. 9 CFR 316.9 - Products to be marked with official marks.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... marks. 316.9 Section 316.9 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... liver, beef tongue, and beef heart which has been inspected and passed shall be marked with the official... round, flank, loin, rib, plate, brisket, chuck, and shank are primal parts of beef carcasses. Veal...

  10. Management of Patient Care in Hemodialysis While Focusing on Cardiovascular Disease Events and the Atypical Role of Hyper- and/or Hypotension: A Systematic Review

    PubMed Central

    Khan, Amer Hayat; Syed Sulaiman, Syed Azhar; Khan, Irfanullah

    2016-01-01

    Background. Hemodialysis related hemodynamic instability is a major but an underestimated issue. Moreover, cardiovascular events are the leading cause of morbidity and mortality associated with blood pressure in hemodialysis patients. However, there have been many controversies regarding the role and management of hyper- and/or hypotension during hemodialysis that needs to be addressed. Objective. To critically review the available published data on the atypical role of hyper- and/or hypotension in cardiovascular associated morbidity and mortality in patients on hemodialysis and to understand the discrepancies in this context. Methods. A comprehensive search of literature employing electronic as well as manual sources and screening 2783 papers published between Jan 1980 and Oct 2015 was conducted to collect, identify, and analyze relevant information through peer-reviewed research articles, systematic reviews, and other published works. The cardiovascular events, including accelerated atherosclerotic cardiovascular disease (ASCVD), stroke, heart failure, myocardial infarction, myocardial ischemia, and stress induced myocardial dysfunction, leading to death were considered relevant. Results. A total of 23 published articles met the inclusion criteria and were included for in-depth review and analysis to finalize a comprehensive systematic review article. All the studies showed a significant association between the blood pressure and cardiovascular disease events in hemodialysis patients. Conclusions. Both intradialytic hypertension/hypotension episodes are major risk factors for cardiovascular mortality with a high percentage of probable causality; however, clinicians are faced with a dilemma on how to evaluate blood pressure and treat this condition. PMID:27833921

  11. Pavement marking performance analysis

    DOT National Transportation Integrated Search

    2009-06-30

    This research evaluated pavement marking performance and developed useful degradation models for thermoplastic : and paint pavement markings which can help North Carolina meet the pending FHWA minimum retroreflectivity : requirements. The impacts of ...

  12. Predictors of Arterial Blood Pressure Control During Deliberate Hypotension with Sodium Nitroprusside in Children

    PubMed Central

    Spielberg, David R; Barrett, Jeffrey S; Hammer, Gregory B; Drover, David R; Reece, Tammy; Cohane, Carol A; Schulman, Scott R

    2014-01-01

    Background Sodium nitroprusside (SNP) is used to decrease arterial blood pressure (BP) during certain surgical procedures. There are limited data regarding efficacy of BP control with SNP. There are no data on patient and clinician factors that affect BP control. We evaluated the dose-response relationship of SNP in infants and children undergoing major surgery and performed a quantitative assessment of BP control. Methods One hundred fifty-three subjects at 7 sites received a blinded infusion followed by open-label SNP during operative procedures requiring controlled hypotension. SNP was administered by continuous infusion and titrated to maintain BP control (mean arterial BP [MAP] within ±10% of clinician-defined target). BP was recorded using an arterial catheter. Statistical Process Control methodology was used to quantify BP control. A multivariable model assessed the effects of patient and procedural factors. Results BP was controlled an average 45.4% (SD 23.9%, 95% CI 41.5%-49.18%) of the time. Larger changes in infusion rate were associated with worse BP control (7.99% less control for 1 mcg•kg−•min− increase in average titration size, p=0.0009). A larger difference between a patient's baseline and target MAP predicted worse BP control (0.93% worse control per 1 mmHg increase in MAP difference, p=0.0013). Both effects persisted in multivariable models. Conclusions : SNP was effective in reducing BP. However, BP was within the target range less than half of the time. No clinician or patient factors were predictive of BP control, although two inverse relationships were identified. These relationships require additional study and may be best coupled with exposure-response modeling to propose improved dosing strategies when using SNP for controlled hypotension in the pediatric population. PMID:25099924

  13. Droxidopa in patients with neurogenic orthostatic hypotension associated with Parkinson's disease (NOH306A).

    PubMed

    Hauser, Robert A; Hewitt, L Arthur; Isaacson, Stuart

    2014-01-01

    Neurogenic orthostatic hypotension (nOH) is common in Parkinson's disease (PD), and represents a failure to generate norepinephrine responses appropriate for postural change. Droxidopa (L-threo-3,4-dihydroxyphenylserine) is an oral norepinephrine prodrug. Interim analyses of the initial patients enrolled in a multicenter, randomized, double-blind, placebo-controlled phase 3 trial of droxidopa for nOH in PD (ClinicalTrials.gov Identifier: NCT01176240). PD patients with documented nOH underwent ≤ 2 weeks of double-blind droxidopa or placebo dosage optimization followed by 8 weeks of maintenance treatment (100-600 mg t.i.d.). The primary efficacy measure was change in Orthostatic Hypotension Questionnaire (OHQ) composite score from baseline to Week 8. Key secondary variables included dizziness/lightheadedness score (OHQ item 1) and patient-reported falls. Among 24 droxidopa and 27 placebo recipients, mean OHQ composite-score change at Week 8 was -2.2 versus -2.1 (p = 0.98); in response to this pre-planned futility analysis, the study was temporarily stopped and all data from these patients were considered exploratory. At Week 1, mean dizziness/lightheadedness score change favored droxidopa by 1.5 units (p = 0.24), with subsequent numerical differences favoring droxidopa throughout the observation period, and at Week 1, mean standing systolic blood-pressure change favored droxidopa by 12.5 mmHg (p = 0.04). Compared with placebo, the droxidopa group exhibited an approximately 50% lower rate of reported falls (p = 0.16) and fall-related injuries (post-hoc analysis). This exploratory analysis of a small dataset failed to show benefit of droxidopa, as compared with placebo by the primary endpoint. Nonetheless, there were signals of potential benefit for nOH, including improvement in dizziness/lightheadedness and reduction in falls, meriting evaluation in further trials.

  14. Predictors of arterial blood pressure control during deliberate hypotension with sodium nitroprusside in children.

    PubMed

    Spielberg, David R; Barrett, Jeffrey S; Hammer, Gregory B; Drover, David R; Reece, Tammy; Cohane, Carol A; Schulman, Scott R

    2014-10-01

    Sodium nitroprusside (SNP) is used to decrease arterial blood pressure (BP) during certain surgical procedures. There are limited data regarding efficacy of BP control with SNP. There are no data on patient and clinician factors that affect BP control. We evaluated the dose-response relationship of SNP in infants and children undergoing major surgery and performed a quantitative assessment of BP control. One hundred fifty-three subjects at 7 sites received a blinded infusion followed by open-label SNP during operative procedures requiring controlled hypotension. SNP was administered by continuous infusion and titrated to maintain BP control (mean arterial BP [MAP] within ±10% of clinician-defined target). BP was recorded using an arterial catheter. Statistical process control methodology was used to quantify BP control. A multivariable model assessed the effects of patient and procedural factors. BP was controlled an average 45.4% (SD 23.9%; 95% CI, 41.5%-49.18%) of the time. Larger changes in infusion rate were associated with worse BP control (7.99% less control for 1 μg·kg·min increase in average titration size, P = 0.0009). A larger difference between a patient's baseline and target MAP predicted worse BP control (0.93% worse control per 1-mm Hg increase in MAP difference, P = 0.0013). Both effects persisted in multivariable models. SNP was effective in reducing BP. However, BP was within the target range less than half of the time. No clinician or patient factors were predictive of BP control, although 2 inverse relationships were identified. These relationships require additional study and may be best coupled with exposure-response modeling to propose improved dosing strategies when using SNP for controlled hypotension in the pediatric population.

  15. Intra-dialytic blood oxygen saturation (SO2): association with dialysis hypotension (the SOGLIA Study).

    PubMed

    Mancini, E; Perazzini, C; Gesualdo, L; Aucella, F; Limido, A; Scolari, F; Savoldi, S; Tramonti, M; Corazza, L; Atti, M; Severi, S; Bolasco, P; Santoro, A

    2017-12-01

    Intradialytic hypotension (IDH) has a dramatic impact on the main outcomes of dialysis patients. Early warning of hemodynamic worsening during dialysis would enable preventive measures to be taken. Blood oxygen saturation (SO 2 ) is used for hemodynamic monitoring in the critical care setting and may provide useful information about IDH onset. To evaluate whether short- and medium-term variations in the SO 2 signal (ST-SO 2var , MT-SO 2var ,) during dialysis are a predictor of IDH. In this 3-month observational cohort study, 51 hypotension-prone chronic hemodialysis (HD) patients, with vascular access by arteriovenous fistula (AVF) or central venous catheter (CVC), were enrolled. Continuous non-invasive blood SO 2 was monitored (fc = 0.2 Hz) by an optical sensor on the arterial line of the extracorporeal circulation; blood pressure (every 30 min), symptoms and their time of appearance were noted. Predictive power of IDH was expressed by the area under curve (AUC) sensitivity and specificity based on intradialytic variations in SO 2 . A total of 1290 HD sessions were analyzed. Overall, off-line ST-SO 2var analysis proved able to correctly predict IDH in 67 % of the sessions where IDH occurred. The best predictive performance was found in the presence of highly arterialized AVF (SO 2  > 95 %) (75 % sensitivity; AUC 0.825; p < 0.05). On the contrary, in sessions with CVC, IDH prediction proved more efficient by MT-SO 2var (AUC 0.575; p = 0.01). Intradialytic SO 2 variability could be a valid parameter to detect in advance the hemodynamic worsening that precedes IDH. Appropriate timely intervention could help prevent IDH onset.

  16. Idiopathic orthostatic hypotension: Recent data (eleven cases) and review of the literature

    NASA Technical Reports Server (NTRS)

    Ninet, J.; Annat, G.; Boisson, D.; Holzhapfel, L.; Vincent, M.; Peyrin, L.; Michel, D.; Schott, B.; Devic, M.; Levrat, R.

    1981-01-01

    Eight cases of Shy-Drager syndrome and three of Bradbury-Eggleston idiopathic orthostatic hypotension were examined. In all cases, examination of circulatory reflexes showed major dysfunction of the sympathetic vasoconstrictor system. Anomalies in the vagal cardiomoderator system were less constant. Normal urinary elimination of catecholamines was recorded daily. Characteristically, no elevation of blood or urine norepinephrine levels were found in orthostatism. Insulin hypoglycemia normally raised urinary adrenalin elimination in three of ten patients. Plasma dopa-beta-hydroxylase activity was normal. Renin-angiotensin-aldosterone system showed variable activity at basal state but usually rose during orthostatism. On the average, very low homovanillic acid levels were found in cerebrospinal fluid before and after probenecid; hydroxyindolacetic acid was normal. Cerebral autoregulation had deteriorated in two of four cases. Physiopathologically the two clinical types are indistinguishable with or without central neurological signs.

  17. A non-human primate model for investigating drug-induced risk of orthostatic hypotension and sympathetic dysfunction: Preclinical correlate to a clinical test.

    PubMed

    Bhatt, Siddhartha; Foote, Stephen; Smith, Andrew; Butler, Paul; Steidl-Nichols, Jill

    2015-01-01

    Drug induced orthostatic hypotension (OH) is an important clinical concern and can be an unexpected hurdle during drug development. OH is defined as an abnormal decrease in blood pressure (BP) triggered by a rapid postural change. The sympathetic nervous system is critical for controlling normal cardiovascular function and compensatory responses to changes in posture. Thus, OH can also serve as a surrogate indicator of sympathetic dysfunction. However, preclinical conscious models for investigating risk of OH and/or sympathetic dysfunction are lacking. Herein, we describe a conscious nonhuman primate (NHP) model which mimics the widely used clinical tilt table test for OH. Male, Cynomolgus NHPs (n = 7-8) implanted with radio-telemetry transmitters were placed in modified tilt chairs in a supine position. Subsequently, a 90° head up tilt was performed for 3 min followed by return to the supine position. BP and heart rate were continuously monitored. Test compounds were administered either intravenously or via oral gavage in a crossover design, with blood samples collected at the end of the each tilt to assess total drug concentrations. Tilt responses were assessed following treatment with positive control compounds that cause sympathetic dysfunction; hexamethonium (ganglionic blocker) and prazosin (alpha-1 adrenergic receptor antagonist). Both compounds induced marked OH as evidenced by robust and sustained BP reduction in response to a head up tilt (decrease of 25-35 mmHg for hexamethonium, decrease of 21-44 mmHg for prazosin). OH incidence rates increased in a dose-dependent manner. OH incidences following treatment with minoxidil (vasodilator) were markedly lower to those observed with hexamethonium and prazosin indicating the role of sympathetic dysfunction in causing OH. These data demonstrate that the NHP tilt test is a valuable model for investigating OH risk. This model fills an important preclinical gap for assessing such a safety concern and can be

  18. GCF Mark IV development

    NASA Technical Reports Server (NTRS)

    Mortensen, L. O.

    1982-01-01

    The Mark IV ground communication facility (GCF) as it is implemented to support the network consolidation program is reviewed. Changes in the GCF are made in the area of increased capacity. Common carrier circuits are the medium for data transfer. The message multiplexing in the Mark IV era differs from the Mark III era, in that all multiplexing is done in a GCF computer under GCF software control, which is similar to the multiplexing currently done in the high speed data subsystem.

  19. A non-interventional comparative study of the 20:1 combination of cafedrine/theodrenaline versus ephedrine for the treatment of intra-operative arterial hypotension: the 'HYPOTENS' study design and rationale.

    PubMed

    Eberhart, Leopold; Geldner, Götz; Huljic, Susanne; Marggraf, Kerstin; Keller, Thomas; Koch, Tilo; Kranke, Peter

    2018-06-01

    To compare the effectiveness of 20:1 cafedrine/theodrenaline approved for use in Germany to ephedrine in the restoration of arterial blood pressure and on post-operative outcomes in patients with intra-operative arterial hypotension of any origin under standard clinical practice conditions. 'HYPOTENS' is a national, multi-center, prospective, open-label, two-armed, non-interventional study. Effectiveness and post-operative outcome following cafedrine/theodrenaline or ephedrine therapy will be evaluated in two cohorts of hypotensive patients. Cohort A includes patients aged ≥50 years with ASA-classification 2-4 undergoing non-emergency surgical procedures under general anesthesia. Cohort B comprises patients undergoing Cesarean section under spinal anesthesia. Participating surgical departments will be assigned to a treatment arm by routinely used anti-hypotensive agent. To minimize bias, matched department pairs will be compared in a stratified selection process. The composite primary end-point is the lower absolute deviation from individually determined target blood pressure (IDTBP) and the incidence of heart rate ≥100 beats/min in the first 15 min. Secondary end-points include incidence and degree of early post-operative delirium (cohort A), severity of fetal acidosis in the newborn (cohort B), upper absolute deviation from IDTBP, percentage increase in systolic blood pressure, and time to IDTBP. This open-label, non-interventional study design mirrors daily practice in the treatment of patients with intra-operative hypotension and ensures full treatment decision autonomy with respect to each patient's individual condition. Selection of participating sites by a randomization process addresses bias without interfering with the non-interventional nature of the study. First results are expected in 2018. ClinicalTrials.gov identifier: NCT02893241; DRKS identifier: DRKS00010740.

  20. Medicines can affect thermoregulation and accentuate the risk of dehydration and heat-related illness during hot weather.

    PubMed

    Westaway, K; Frank, O; Husband, A; McClure, A; Shute, R; Edwards, S; Curtis, J; Rowett, D

    2015-08-01

    Hot days are increasingly common and are often associated with increased morbidity and mortality, especially in the elderly. Most heat-related illness and heat-related deaths are preventable. Medicines may accentuate the risk of dehydration and heat-related illness, especially in elderly people taking multiple medicines, through the following mechanisms: diuresis and electrolyte imbalance, sedation and cognitive impairment, changed thermoregulation, reduced thirst recognition, reduced sweat production, and hypotension and reduced cardiac output. Commonly used medicines that may significantly increase the risk include diuretics, especially when combined with an angiotensin converting enzyme (ACE) inhibitor or an angiotensin II receptor blocker (ARB), anticholinergics and psychotropics. Initiation of individualized preventive measures prior to the start of the hot weather season, which includes a review of the patient and their medicines to identify thermoregulatory issues, may reduce the risk of heat-related illness or death. © 2015 John Wiley & Sons Ltd.

  1. Association between postexercise hypotension and long-term training-induced blood pressure reduction: a pilot study.

    PubMed

    Hecksteden, Anne; Grütters, Teresa; Meyer, Tim

    2013-01-01

    The interindividual variability in the efficacy of regular endurance exercise to lower blood pressure is high. Therefore, to optimize training prescriptions, predictors would be desirable. The main hypothesis of the present study was an association between postexercise hypotension after an exhaustive exercise test and chronic blood pressure reductions in response to an endurance training program. Uncontrolled prospective training study. University department. Healthy untrained subjects were recruited by flyers. Inclusion criteria were age 30 to 60 years, body mass index 25 to 35 kg/m(2), untrained status (<1 hour/week regular activity; V[Combining Dot Above]O(2max) < 45 mL·min(-1)·kg(-1)), blood pressure 150/95 mm Hg, nonsmoker; 14 subjects were included, 12 could be analyzed. Walking/running 4 times per week at 60% heart rate reserve for 4 weeks. Difference in blood pressure from the initial resting value to 1 and 24 hours after the initial test (acute) and the resting value before the final test (chronic), respectively. Initial resting systolic blood pressure was 134 ± 18 mm Hg. Values were significantly reduced at all time points thereafter (1 hour: 125 ± 13 mm Hg; 24 hours: 128 ± 12 mm Hg; final: 125 ± 18 mm Hg). Acute and chronic changes correlated significantly (1 hour: P = 0.003; r = 0.77; 24 hours: P = 0.017; r = 0.67). Results for diastolic blood pressure were comparable yet less pronounced. The magnitude of postexercise hypotension is a promising candidate for the prediction of individual blood pressure-related training efficacy. Easily determined, it might be used to improve training prescriptions. However, further studies are needed to assess predictive accuracy.

  2. [Unusual and fatal type of burn injury: hot air sauna burn].

    PubMed

    García-Tutor, E; Koljonen, V

    2007-01-01

    Sauna bathing is a popular recreational activity in Finland and is generally considered safe even for pregnant women and patients suffering from heart problems; but mixing alcohol with sauna bathing can be hazardous. In the normal Finnish recreational sauna the temperature is usually between 80 and 90 degrees C. A wide variety of burn injuries, in all age groups, are related to sauna bathing; scalds and contact burns account for over 85% while hot air, steam and flame burns for only 15%. Dehydration in patients under the influence of alcohol heightens the risk of hypotension which impairs skin blood circulation. This increased warming of the skin is an effect that is more marked on the outer and upper parts of the body exposed to hot air. Such patients require intensive care on admission: fluid replacement according to the Parkland formula, forced diuresis and immediate correction of acidosis and myoglobinuria. These patients have significant rhabdomyolysis on admission. The best predictor of survival is the creatine kinase level on the second post-injury day. CT scans are necessary to diagnose the underlying conditions of unconsciousness. The necrotic area extends to subcutaneous fat tissue and even to the underlying muscles. The level of excision is typically fascial and, in some areas, layers of the muscle must be removed. Owing to the popularity of sauna bathing throughout the world, it is important to know the extent of damage in this type of injury, in order not to underestimate the severity of such lesions.

  3. Heavily T2-weighted MR myelography vs CT myelography in spontaneous intracranial hypotension.

    PubMed

    Wang, Y-F; Lirng, J-F; Fuh, J-L; Hseu, S-S; Wang, S-J

    2009-12-01

    To assess the diagnostic accuracy of heavily T2-weighted magnetic resonance myelography (MRM) in patients with spontaneous intracranial hypotension (SIH). Patients with SIH were recruited prospectively, and first underwent MRM and then computed tomographic myelography (CTM). The results of MRM were validated with the gold standard, CTM, focusing on 1) CSF leaks along the nerve roots, 2) epidural CSF collections, and 3) high-cervical (C1-3) retrospinal CSF collections. Comparisons of these 3 findings between the 2 studies were made by kappa statistics and agreement rates. Targeted epidural blood patches (EBPs) were placed at the levels of CSF leaks if supportive treatment failed. Nineteen patients (6 men and 13 women, mean age 37.9 +/- 8.6 years) with SIH completed the study. MRM did not differ from CTM in the detection rates of CSF leaks along the nerve roots (84% vs 74%, p = 0.23), high-cervical retrospinal CSF collections (32% vs 16%, p = 0.13), and epidural CSF collections (89% vs 79%, p = 0.20). MRM demonstrated more spinal levels of CSF leaks (2.2 +/- 1.7 vs 1.5 +/- 1.5, p = 0.011) and epidural collections (12.2 +/- 5.9 vs 7.1 +/- 5.8, p < 0.001) than CTM. The overall level-by-level concordance was substantial for CSF leaks along the nerve roots (C1-L3) (kappa = 0.71, p < 0.001, agreement = 95%) and high-cervical retrospinal CSF collections (C1-3) (kappa = 0.73, p < 0.001, agreement = 92%), and moderate for epidural CSF collections (C1-L3) (kappa = 0.47, p < 0.001, agreement = 72%). Ten of the 14 patients (71%) receiving targeted EBPs experienced sustained symptomatic relief after a single attempt. Heavily T2-weighted magnetic resonance myelography was accurate in localizing CSF leaks for patients with spontaneous intracranial hypotension. This noninvasive technique may be an alternative to computed tomographic myelography before targeted epidural blood patches.

  4. 49 CFR 172.304 - Marking requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Marking requirements. 172.304 Section 172.304 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... SECURITY PLANS Marking § 172.304 Marking requirements. (a) The marking required in this subpart— (1) Must...

  5. Classroom Mark-Recapture with Crickets

    ERIC Educational Resources Information Center

    Whiteley, Andrew R.; Woolfe, Jennifer; Kennedy, Kathleen; Oberbillig, David; Brewer, Carol

    2007-01-01

    Mark-recapture techniques are commonly used by ecologists to estimate abundance of naturally occurring animals and are an important component of ecology curricula. This investigation teaches a mark-recapture technique using store-bought crickets in 10-gallon aquaria and provides an inexpensive way to teach students about mark-recapture in a real…

  6. Effects of the novel norepinephrine prodrug, droxidopa, on ambulatory blood pressure in patients with neurogenic orthostatic hypotension.

    PubMed

    Kaufmann, Horacio; Norcliffe-Kaufmann, Lucy; Hewitt, L Arthur; Rowse, Gerald J; White, William B

    2016-10-01

    The prodrug droxidopa increases blood pressure (BP) in patients with neurogenic orthostatic hypotension. The BP profile of droxidopa in neurogenic orthostatic hypotension patients (n = 18) was investigated using ambulatory BP monitoring. Following dose optimization and a washout period, 24-hour "off-drug" data were collected. "On-drug" assessment was conducted after 4-5 weeks of droxidopa treatment (mean dose, 444 mg, three times daily). Ambulatory monitoring off drug revealed that 90% of patients already had abnormalities in the circadian BP profile and did not meet criteria for normal nocturnal BP dipping. On treatment, both overall mean 24-hour systolic and diastolic BPs were higher compared to off drug (137/81 mm Hg vs. 129/76 mm Hg; P = .017/.002). Mean daytime systolic BP was significantly higher with droxidopa (8.4 ± 3.1 mm Hg; P = .014). Although nocturnal BP was not significantly higher on droxidopa versus off treatment (P = .122), increases in nocturnal (supine) BP ≥10 mm Hg were observed in four cases (22%). Severe supine systolic hypertensive readings at night (>200 mm Hg) were captured in one case and only while on treatment. These data demonstrate that ambulatory BP monitoring is useful to evaluate the circadian BP profile after initiating treatment with a pressor agent. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  7. New fluoroprostaglandin F(2alpha) derivatives with prostanoid FP-receptor agonistic activity as potent ocular-hypotensive agents.

    PubMed

    Nakajima, Tadashi; Matsugi, Takeshi; Goto, Wakana; Kageyama, Masaaki; Mori, Nobuaki; Matsumura, Yasushi; Hara, Hideaki

    2003-12-01

    To find new prostanoid FP-receptor agonists possessing potent ocular-hypotensive effects with minimal side effects, we evaluated the agonistic activities of newly synthesized prostaglandin F(2alpha) derivatives for the prostanoid FP-receptor both in vitro and in vivo. The iris constrictions induced by the derivatives and their effects on melanin content were examined using cat isolated iris sphincters and cultured B16 melanoma cells, respectively. The effects of derivative ester forms on miosis and intraocular pressure (IOP) were evaluated in cats and cynomolgus monkeys, respectively. Of these derivatives, 6 out of 12 compounds were more potent iris constrictors, with EC(50) values of 0.6 to 9.4 nM, than a carboxylic acid of latanoprost (EC(50)=13.6 nM). A carboxylic acid of latanoprost (100 microM) significantly increased the melanin content of cultured B16 melanoma cells, but some 15,15-difluoro derivatives, such as AFP-157 and AFP-172, did not. Topically applied AFP-168, AFP-169 and AFP-175 (isopropyl ester, methyl ester and ethyl ester forms, respectively, of AFP-172) induced miosis in cats more potently than latanoprost. AFP-168 (0.0005%) reduced IOP to the same extent as 0.005% latanoprost (for at least 8 h). These findings indicate that 15,15-difluoroprostaglandin F(2alpha) derivatives, especially AFP-168, have more potent prostanoid FP-receptor agonistic activities than latanoprost. Hence, AFP-168 may be worthy of further evaluation as an ocular-hypotensive agent.

  8. Dietary calcein marking of shovelnose sturgeon and the effect of sunlight on mark retention

    USGS Publications Warehouse

    Honeyfield, D.C.; Kindschi, G.A.; Bell, T.A.; Mohler, J.W.

    2011-01-01

    Calcein, a fluorochrome dye, is a potential fish-marking agent that has not been evaluated in sturgeon. Shovelnose sturgeon Scaphirhynchus platorynchus (average weight, 9.7 g) were fed calcein, immersed in a calcein bath, or left unmarked to determine calcein mark intensity. In the first study, six treatments were evaluated in a two-by-three factorial arrangement. Feed was formulated with 2.0 g of SE-MARK/kg either as powder or in an encapsulated form. Sturgeon were fed the test diets for 5, 10, or 15 d. They readily ate feed containing powdered or encapsulated calcein. Sturgeon fed powdered calcein had more brilliant marks than those fed encapsulated calcein (8.27 versus 4.66 lm; P < 0.03) 6 months postexposure. Fish fed calcein for 15 d (11.26 lm) were more brilliant (P < 0.002) than fish fed for either 5 d (3.02 lm) or 10 d (5.11 lm). Post hoc comparison of the three treatment groups showed that sturgeon fed powdered calcein for 15 d (14.06 lm) were brighter (P < 0.01) than fish fed encapsulated calcein (8.46 lm) or fish immersed in calcein (9.68 lm). In the second study, previouslymarked sturgeon were exposed to sunlight for 14months to determine their retention of calcein marks. Dorsal marks were no longer visible on fish exposed to 100% sunlight after 8 weeks. Most but not all fish exposed to 20% sunlight had no discernable dorsalmarks after 8 weeks, but ventral marks at the pectoral fin girdle were present on all fish in the 0% and 20% sunlight exposure treatments. Feeding calcein for 15 d appears to have excellent potential for practical application, such as distinguishing hatchery-reared from wild fish. Ventral calcein marks remained visible after 14 months of exposure to 20% sunlight when sturgeon were reared in clear water. ?? American Fisheries Society 2011.

  9. 46 CFR 185.602 - Hull markings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Hull markings. 185.602 Section 185.602 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) OPERATIONS Markings Required § 185.602 Hull markings. (a) Each vessel must be marked as required by part 67...

  10. 14 CFR 23.1555 - Control markings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Markings and Placards § 23.1555 Control markings. (a) Each cockpit control, other than primary flight controls and simple push button type starter switches, must be plainly marked as to its function and method... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Control markings. 23.1555 Section 23.1555...

  11. 14 CFR 23.1555 - Control markings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Markings and Placards § 23.1555 Control markings. (a) Each cockpit control, other than primary flight controls and simple push button type starter switches, must be plainly marked as to its function and method... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Control markings. 23.1555 Section 23.1555...

  12. 14 CFR 23.1555 - Control markings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Markings and Placards § 23.1555 Control markings. (a) Each cockpit control, other than primary flight controls and simple push button type starter switches, must be plainly marked as to its function and method... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Control markings. 23.1555 Section 23.1555...

  13. 14 CFR 23.1555 - Control markings.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Control markings. 23.1555 Section 23.1555... Markings and Placards § 23.1555 Control markings. (a) Each cockpit control, other than primary flight controls and simple push button type starter switches, must be plainly marked as to its function and method...

  14. Effect of the exercise of walkers performed in public squares with spontaneous or prescribed intensity on post-exercise hypotension.

    PubMed

    Silva, Taís Feitosa da; Souza, Alesandra Araújo de; Lima, Fabiano Ferreira de; Suassuna, Jennifer Ariely Sales; Couto, Henrique Eduardo Paiva Lira do; Tenório, Gustavo Roque; Silva, Maria Irene de Andrade Gomes; Dias, Guilherme Leandebal Bonifácio; Silva, Alexandre Sérgio

    2017-07-20

    To quantify the intensity adopted by walkers in public squares and check the occurrence and magnitude of post-exercise hypotension in the spontaneously adopted intensity and in a prescribed intensity. In 98 volunteers (38 of them being hypertensive), walkers in public squares of the city of João Pessoa, State of Paraíba, Brazil, we have identified the intensity of a usual training monitored by heart rate and we have investigated the occurrence and magnitude of post-exercise hypotension. Subsequently, participants were instructed to walk with moderate intensity. Blood pressure was measured after rest and during post-exercise recovery. Of the total participants, 41% of the hypertensive and 36% of the normotensive individuals walked with light intensity. With the prescription, intensity increased to 55% and 52%, for the hypertensive and normotensive individuals, respectively. In the usual and prescribed intensity, the hypertensive individuals had post-exercise hypotension of -3.7±11.6 mmHg and -4.72±12.8 mmHg, respectively. There was no correlation between post-exercise hypotension and the initial systolic component of the hypertensive individuals (r2 = 0.2; p < 0.002). Walkers in public squares choose light intensity for walking. When they exercise with the prescribed intensity, they increase the intensity, but the magnitude of the PEH is not increase with this guidance. Quantificar a intensidade adotada por caminhantes em praças públicas e verificar a ocorrência e a magnitude da hipotensão pós-exercício na intensidade espontaneamente adotada e em uma intensidade prescrita. Em 98 voluntários (38 hipertensos), caminhantes em praças públicas da cidade de João Pessoa, PB, identificamos a intensidade de um treino habitual monitorada por meio da frequência cardíaca e averiguamos a ocorrência e magnitude de hipotensão pós-exercício. Posteriormente, os participantes foram instruídos a caminhar com intensidade moderada. A pressão arterial foi aferida ap

  15. 27 CFR 28.144 - Export marks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Export marks. 28.144... § 28.144 Export marks. (a) General Requirement. In addition to the marks and brands required to be... brewer shall mark the word “Export” on each container or case of beer, or the words “Beer concentrate for...

  16. 27 CFR 28.103 - Export marks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Export marks. 28.103... Manufacturing Bonded Warehouse § 28.103 Export marks. (a) General. In addition to the marks and brands required... provisions of part 19 of this chapter, the proprietor shall mark the word “Export” on the Government side of...

  17. 27 CFR 28.193 - Export marks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Export marks. 28.193... Drawback Filing of Notice and Removal § 28.193 Export marks. In addition to the marks and brands required... chapter, the exporter shall mark the word “Export” on the Government side of each case or Government head...

  18. 27 CFR 28.154 - Export marks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Export marks. 28.154..., for Exportation or Transfer to a Foreign-Trade Zone § 28.154 Export marks. In addition to the marks... provisions of part 19 of this chapter, the proprietor shall mark the word “Export” on the Government side of...

  19. 1L Mark-IV Target Design Review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koehler, Paul E.

    This presentation includes General Design Considerations; Current (Mark-III) Lower Tier; Mark-III Upper Tier; Performance Metrics; General Improvements for Material Science; General Improvements for Nuclear Science; Improving FOM for Nuclear Science; General Design Considerations Summary; Design Optimization Studies; Expected Mark-IV Performance: Material Science; Expected Mark-IV Performance: Nuclear Science (Disk); Mark IV Enables Much Wider Range of Nuclear-Science FOM Gains than Mark III; Mark-IV Performance Summary; Rod or Disk? Center or Real FOV?; and Project Cost and Schedule.

  20. The research of laser marking control technology

    NASA Astrophysics Data System (ADS)

    Zhang, Qiue; Zhang, Rong

    2009-08-01

    In the area of Laser marking, the general control method is insert control card to computer's mother board, it can not support hot swap, it is difficult to assemble or it. Moreover, the one marking system must to equip one computer. In the system marking, the computer can not to do the other things except to transmit marking digital information. Otherwise it can affect marking precision. Based on traditional control methods existed some problems, introduced marking graphic editing and digital processing by the computer finish, high-speed digital signal processor (DSP) control marking the whole process. The laser marking controller is mainly contain DSP2812, digital memorizer, DAC (digital analog converting) transform unit circuit, USB interface control circuit, man-machine interface circuit, and other logic control circuit. Download the marking information which is processed by computer to U disk, DSP read the information by USB interface on time, then processing it, adopt the DSP inter timer control the marking time sequence, output the scanner control signal by D/A parts. Apply the technology can realize marking offline, thereby reduce the product cost, increase the product efficiency. The system have good effect in actual unit markings, the marking speed is more quickly than PCI control card to 20 percent. It has application value in practicality.

  1. Evidence for vestibular dysfunction in orthostatic hypotension.

    PubMed

    Aoki, Mitsuhiro; Sakaida, Yuzuru; Tanaka, Kunihiko; Mizuta, Keisuke; Ito, Yatsuji

    2012-03-01

    There is little definitive evidence of the clinical significance of the vestibular-cardiovascular reflex in humans, despite the fact that the vestibular system is known to contribute to cardiovascular control in animals. The present study involved 248 dizzy patients (127 male patients and 121 female patients) aged 65 years and younger. We classified all participants into three groups based on their vestibular evoked myogenic potential (VEMP) responses; absent VEMP, asymmetry VEMP and normal VEMP. To investigate the effect of the otolith disorder, which was estimated by the VEMP, on the orthostatic blood pressure responses, the subjects' systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate were monitored during the orthostatic test after they actively stood up. The male patients in the absent VEMP group had a significant drop in their DBP at 1 min after active standing up (P < 0.05) without any change in their SBP. Conversely, male patients in the asymmetry VEMP and normal VEMP groups showed a significant increase in the SBP at 1 min after active standing up (P < 0.05). Female patients in the absent VEMP group did not show any significant drop in their blood pressure after standing up (P > 0.05). In the entire group of participants, a total of 19.6% of the patients in the absent VEMP group fulfilled the criteria for orthostatic hypotension (OH), which was significantly > the 8.6% of patients in the normal VEMP group and the 7.2% in the asymmetry VEMP group (P < 0.05). Our results suggest that vestibular disorders due to the dysfunction of otolith organs provoke OH.

  2. Orthostatic Hypotension and Mortality in Elderly Frail Patients

    PubMed Central

    Freud, Tamar; Punchik, Boris; Yan, Press

    2015-01-01

    Abstract Orthostatic hypotension (OH) is a common problem in the elderly age group, and some studies have reported an association between OH and increased mortality. We evaluated possible associations between OH and mortality in a retrospective study of frail elderly patients who came for a comprehensive geriatric assessment. The study included all patients ≥65 years who were assessed in the outpatient Comprehensive Geriatric Assessment Unit. Data were collected from the computerized medical record, including blood pressure, sociodemographic data, lifestyle, falls, pulse rate, body mass index, functional and cognitive status, and comorbidity. Data on mortlaity were also collected. The study population consisted of 571 patients who underwent assessment over a 9-year study period. The mean age was 83.7 ± 6.1, 35.9% were males, and 183 (32.1%) were diagnosed with OH. Systolic OH (OHS) was more common than diastolic OH (25.2% vs 15.6%). In univariate analyses, OHS was associated with increased overall mortality. Over the follow-up period, 30.2% of the OHS patients died compared with 22.3% (P = 0.037), but in the Cox models there was no statistically significant associations between OHS and overall mortality. In contrast, age, burden of comorbidity, a low high-density lipoprotein level, and low creatinine clearance were independent predictors of increased overall mortality. In a population of frail elderly patients with a high burden of comorbidity, OH was not an independent risk factor for overall mortality. PMID:26091470

  3. Use of an Impedance Threshold Device in Spontaneously Breathing Patients with Hypotension Secondary to Trauma: An Observational Cohort Feasibility Study

    DTIC Science & Technology

    2014-09-09

    hypotensive patient. Crystalloid infusion is not necessarily benign.1,2 Difficult vascular access, hemodilution, acidosis , decreased oxygen delivery, and...blood pressure, heart rate (HR), respiratory rate, and arterial oxygen saturation (SpO2) were recorded im- mediately before application of the ITD...per minute (p = 0.007). The respiratory rate was constant: 19 (7) breaths before to 18 (4) breaths (p = 0.31) per minute after ITD use. Oxygen

  4. Exercise training hypotension - Implications for plasma volume, renin, and vasopressin

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Sciaraffa, D.; Shvartz, E.; Keil, L. C.; Brock, P. J.

    1981-01-01

    The relation of changes in plasma volume, plasma renin activity and arginine vasopressin to changes in resting blood pressure during exercise training is investigated. Resting supine, sitting, and standing systolic and fifth-phase diastolic blood pressures were measured in ten men before and after an eight-day training period on a cycle ergometer in either a hot (39.8 C) or cool (23.8 C) environment, and compared with plasma volume, renin and vasopressin levels, heart rates, maximal oxygen uptakes, rectal temperatures and sweat rates. Following acclimatization, resting supine and sitting diastolic pressures are observed to decrease by 6 and 9 mm Hg, respectively, while no significant changes are found in the diastolic pressures of the control group or the systolic pressures of either group. Resting plasma volume is found to increase by 12.2% in the controls and by 17.6% after acclimatization following the exercise training. Results suggest that the resting hypotension produced is not attributable to changes in resting plasma volume, renin or vasopressin, although heat acclimatization, which leads to large decreases in plasma volume and increases in vasopressin and renin activity, may be useful in the treatment of hypertension.

  5. The Pathophysiology of Early Hypotension Following Epinephrine-containing Local Anesthetic Infiltration of the Nasal Mucosa in Patients Undergoing Endoscopic Transsphenoidal Hypophysectomy: A Prospective, Observational Study.

    PubMed

    Wiles, Matthew D; Sanders, Matthew I; Sinha, Saurabh; Mirza, Showkat; Andrzejowski, John C

    2017-07-01

    In patients undergoing endoscopic transsphenoidal hypophysectomy, the nasal mucosa is often infiltrated with local anesthetic solutions that contain epinephrine to aid hemostasis. This may, however, result in hemodynamic changes, especially hypotension. We characterized the cardiovascular changes using a LiDCOrapid monitor in 13 patients after the infiltration of 4% articaine containing 1:200,000 epinephrine. Nine (69%) had a >20% decrease in mean arterial pressure at a median time of 116 seconds after the infiltration of articaine with epinephrine. Analysis of the cardiac output data revealed that this was caused by a sustained reduction in systemic vascular resistance. The arterial blood pressure normalized over a period of 60 to 90 seconds secondary to increases in stroke volume and heart rate producing an elevation in cardiac output. Transient hypotension following the infiltration of epinephrine-containing local anesthetics may be caused by epinephrine stimulation of β2-adrenoceptors producing vasodilation.

  6. Analysis of number needed to treat for droxidopa in patients with symptomatic neurogenic orthostatic hypotension.

    PubMed

    François, Clément; Rowse, Gerald J; Hewitt, L Arthur; Vo, Pamela; Hauser, Robert A

    2016-08-18

    Droxidopa is an orally active prodrug that significantly improved dizziness/lightheadedness measured using the Orthostatic Hypotension Symptom Assessment (OHSA) Item 1 in patients with neurogenic orthostatic hypotension (nOH) caused by primary autonomic failure (Parkinson disease, multiple system atrophy, and pure autonomic failure), dopamine β-hydroxylase deficiency, or nondiabetic autonomic neuropathy. The efficacy and safety of droxidopa were assessed by determining the number needed to treat (NNT) and the number needed to harm (NNH). Data collected in randomized, placebo-controlled clinical studies in adults with a clinical diagnosis of symptomatic nOH were pooled for efficacy and safety analyses. NNT and NNH were calculated as reciprocals of the risk difference (difference in event rates) for droxidopa versus placebo. The NNT for droxidopa for improvement in OHSA Item 1 was <10. The NNH for adverse events (AEs) leading to discontinuation in the pooled studies was 81. The likelihood of being helped or harmed (LHH) calculated from pooled analysis of the NNT for ≥2 units of improvement in OHSA Item 1 score and the NNH for discontinuations due to AEs were 7.8, 8.8, 3.1, and 3.5 for weeks 1, 2, 4, and 8 after randomization, respectively. Droxidopa is efficacious for treatment of nOH, with an NNT below 10 and an acceptable tolerability profile with NNH ranging from 23 to 302 in the pooled analysis of frequently occurring AEs. Based on the LHH for the pooled analysis at week 1, droxidopa is 7.8 times more likely than placebo to show a clinical benefit than result in discontinuation because of an AE. ClinicalTrials.gov identifiers: NCT00782340 , first received October 29, 2008; NCT00633880 , first received March 5, 2008; and NCT01176240 , first received July 30, 2010.

  7. Intralipid™ administration attenuates the hypotensive effects of acute intravenous amiodarone overdose in a swine model.

    PubMed

    Xanthos, Theodoros; Psichalakis, Nikolaos; Russell, David; Papalois, Apostolos; Koutsovasilis, Anastasios; Athanasopoulos, Dimitrios; Gkiokas, Georgios; Chalkias, Athanasios; Iacovidou, Nicoletta

    2016-08-01

    To investigate whether a lipid emulsion could counteract the hypotensive effects of amiodarone overdose after an acute intravenous administration and improve 4 h survival in an established model of swine cardiovascular research. Twenty pigs were intubated and instrumented to measure aortic pressures and central venous pressures (CVP). After allowing the animals to stabilize for 60 minutes, amiodarone overdose (1 mg/kg/min) was initiated for a maximum of 20 minutes. Afterwards, the animals were randomized into 2 groups. Group A (n = 10) received 0.9% Normal Saline (NS) and Group B (n = 10) received 20% Intralipid® (ILE). A bolus dose of 2 ml/kg in over 2 min time was initially administered in both groups followed by a 45 min infusion (0.2 ml/kg/min) of either NS or ILE. All animals survived the overdose and all animals survived the monitoring period of 4 hours. Systolic aortic pressure (SpthAorta) (6.90 vs 14.10 mmHg, P = .006) and mean arterial pressure (MAP) (6.10 vs 14.90 mmHg, P = .001) were higher in the ILE group 2 min after the bolus ILE infusion. This difference was maintained for 15 min after ILE infusion for both SpthAorta (7.85 vs 13.15 mmHg, P = .044) and MAP (7.85 vs 13.15 mmHg, P = .042). Animals that received ILE had higher CVP (11.6 vs 15.7 mmHg, P = .046), an effect which was attenuated 2 and 4 hours post administration. Animals receiving ILE were more acidotic (7.21 vs 7.38, P = .048) in the monitoring period compared to animals receiving NS. Intralipid attenuated the hypotensive effects of amiodarone toxicity for a period of 15 minutes compared to animals receiving NS. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Respiratory failure and lethal hypotension due to blue-ringed octopus and tetrodotoxin envenomation observed and counteracted in animal models.

    PubMed

    Flachsenberger, W A

    The effects of crude blue-ringed octopus venom gland extract and tetrodotoxin (TTX) on anaesthetised rats and rabbits were studied. Paralysis of the respiratory musculature causing anoxia and cyanosis was overcome with positive, artificial respiration. The second lethal mechanism of the toxins: rapid and severe hypotension, had to be counteracted peripherally, since neural transmission had been drastically reduced by the toxins. Noradrenaline, d-amphetamine, phenylephrine and methoxamine, agonists acting on vascular adrenergic a-receptors, were tested.

  9. Meetings with Mark Vishik

    NASA Astrophysics Data System (ADS)

    Kalikinskaya, E. I.

    2014-12-01

    Mark Iosifovich Vishik was my husband Vladimir Chepyzhov's advisor during his years as a student in the Faculty of Mechanics and Mathematics at Moscow State University, and afterwards they worked together for almost 30 years. This is why I knew him personally while not being a mathematician myself: we sometimes talked on the phone, and met during common trips and a few holidays. In his last years, after the death of his devoted wife who was also his best friend, my husband and I decided to visit Mark regularly in order to comfort him in his loneliness, and many other of his friends did the same. I can say without exaggeration that Mark loved to talk with me about everyday matters, to reminisce about his wife Asya Moiseevna, their friends and relatives, to tell stories of his youth and the wonderful encounters that had so enriched his life. We had the idea to write down our conversations and publish them as a book. Unfortunately, few such conversations lay ahead. The last one took place in January 2010. We did not write a book, but we did write an article [1], which was published in English in the form of an interview with Mark. The present article is based on our conversations with Mark. Here I will try to recount his memories about people who played an important role in his life.

  10. Swash mark and grain flow

    USGS Publications Warehouse

    Sallenger,, Asbury H.

    1981-01-01

    Swash marks composed entirely of coarse sand are commonly found on coarse-sand beaches. These swash marks are 10 to 30 centimeters in width and a few millimeters to one centimeter in height. Previous observations, mostly on finer-sand beaches, indicate swash marks are seldom over a few millimeters in height and are commonly composed of material readily floated by surface tension (e.g., mica flakes and shell fragments). Swash marks composed of coarse sand have both fining seaward and fining with depth trends in grain size. Apparently, the leading margin of a wave upwash drives a highly concentrated flow of grains in which both grain size and grain velocity decrease with depth. Therefore, large grains are transported at greater velocities than are smaller grains. Thus, at the maximum advance of an upwash, a swash mark is deposited which has the observed fining seaward and fining with depth trends in grain size.

  11. Vascular and renal effects of dopamine during extracellular volume expansion: Role of nitric oxide pathway.

    PubMed

    Costa, María A; Elesgaray, Rosana; Loria, Analía; Balaszczuk, Ana María; Arranz, Cristina

    2006-02-28

    The aim of the study was to determine the possible role of NO-system activation in vascular and renal effects of the dopaminergic system and the probable interaction between both systems during acute volume expansion in rats. Expanded (10% bw) and non-expanded anaesthetized male Wistar rats were treated with haloperidol, a DA receptor antagonist (3 mg/kg bw, ip). Mean arterial pressure, diuresis, natriuresis, renal plasma flow, glomerular filtration rate, nitrites and nitrates excretion (NOx) were determined. NADPH diaphorase activity was measured using a histochemistry technique in kidney, aorta and renal arteries. NOS activity in kidney and aorta from expanded and non-expanded animals was determined with L-[U14C]-arginine substrate, in basal conditions and after DA (1 microM) administration. The hypotensive effect of L-arg and hypertension induced by L-NAME were not modified by haloperidol. This blocker reverted the increase in diuresis, natriuresis and RPF induced by L-arg in both groups. Dopaminergic blockade induced a decrease in NOx excretion and in NADPH-diaphorase activity in glomeruli, proximal tubule and medullar collecting duct and in endothelium and vascular smooth muscle of renal arteries. DA induced an increase in NOS activity in renal medulla and cortex in both groups, but no changes in the aorta were observed. Our results suggest that renal DA would be associated with the renal response induced by NO during extracellular volume expansion. NO-system activation would be one of the mechanisms involved in renal DA activity during saline load, but NO appears not to be involved in DA vascular effects.

  12. Severe bradycardia and hypotension after connecting negative pressure to the subgaleal drain during craniotomy closure.

    PubMed

    Karamchandani, K; Chouhan, R S; Bithal, P K; Dash, H H

    2006-05-01

    Negative pressure drainage systems are often used after craniotomy for evacuation of potential bleeding. There are several reports of haemodynamic disturbances with epidural negative pressure drainage, but such reports are very few for subgaleal drains placed over the bone flap. We report a case in which a patient developed severe cardiovascular disturbances after the vacuum drainage was connected to a subgaleal drain after craniotomy for aneurysm clipping. The patient had no significant cardiac history, had an uneventful intra-operative course and yet developed bradycardia and hypotension, which were reproducible and severe enough to require atropine administration. Anaesthetists must be aware of these effects, so that they can anticipate and treat such complications.

  13. 48 CFR 227.7103-10 - Contractor identification and marking of technical data to be furnished with restrictive markings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... and marking of technical data to be furnished with restrictive markings. 227.7103-10 Section 227.7103... DEFENSE GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Technical Data 227.7103-10 Contractor identification and marking of technical data to be furnished with restrictive markings...

  14. Post-exercise hypotension and heart rate variability response after water- and land-ergometry exercise in hypertensive patients.

    PubMed

    Bocalini, Danilo Sales; Bergamin, Marco; Evangelista, Alexandre Lopes; Rica, Roberta Luksevicius; Pontes, Francisco Luciano; Figueira, Aylton; Serra, Andrey Jorge; Rossi, Emilly Martinelli; Tucci, Paulo José Ferreira; Dos Santos, Leonardo

    2017-01-01

    systemic arterial hypertension is the most prevalent cardiovascular disease; physical activity for hypertensive patients is related to several beneficial cardiovascular adaptations. This paper evaluated the effect of water- and land-ergometry exercise sessions on post-exercise hypotension (PEH) of healthy normotensive subjects versus treated or untreated hypertensive patients. Forty-five older women composed three experimental groups: normotensive (N, n = 10), treated hypertensive (TH, n = 15) and untreated hypertensive (UH, n = 20). The physical exercise acute session protocol was performed at 75% of maximum oxygen consumption (VO2max) for 45 minutes; systolic (SBP), diastolic (DBP) and mean (MBP) blood pressure were evaluated at rest, peak and at 15, 30, 45, 60, 75 and 90 minutes after exercise cessation. Additionally, the heart rate variability (HRV) was analyzed by R-R intervals in the frequency domain for the assessment of cardiac autonomic function. In both exercise modalities, equivalent increases in SBP were observed from rest to peak exercise for all groups, and during recovery, significant PEH was noted. At 90 minutes after the exercise session, the prevalence of hypotension was significantly higher in water- than in the land-based protocol. Moreover, more pronounced reductions in SBP and DBP were observed in the UH patients compared to TH and N subjects. Finally, exercise in the water was more effective in restoring HRV during recovery, with greater effects in the untreated hypertensive group. Our data demonstrated that water-ergometry exercise was able to induce expressive PEH and improve cardiac autonomic modulation in older normotensive, hypertensive treated or hypertensive untreated subjects when compared to conventional land-ergometry.

  15. Wet night visibility of pavement markings.

    DOT National Transportation Integrated Search

    2004-01-01

    This report describes an investigation into the performance of pavement markings in wet night conditions. The performance of a typical pavement marking will degrade when it gets wet. This is a result of the flooding of the marking optics, thereby red...

  16. 9 CFR 317.3 - Approval of abbreviations of marks of inspection; preparation of marking devices bearing...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... marking device containing any official mark or simulation thereof, or any label bearing any such mark or simulation, without the written authority therefor of the Administrator. However, when any such sample label... inspection legend, or simulation thereof, shown in § 312.2(a), § 312.3(a) (only the legend appropriate for...

  17. 9 CFR 317.3 - Approval of abbreviations of marks of inspection; preparation of marking devices bearing...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... marking device containing any official mark or simulation thereof, or any label bearing any such mark or simulation, without the written authority therefor of the Administrator. However, when any such sample label... inspection legend, or simulation thereof, shown in § 312.2(a), § 312.3(a) (only the legend appropriate for...

  18. 9 CFR 317.3 - Approval of abbreviations of marks of inspection; preparation of marking devices bearing...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... marking device containing any official mark or simulation thereof, or any label bearing any such mark or simulation, without the written authority therefor of the Administrator. However, when any such sample label... inspection legend, or simulation thereof, shown in § 312.2(a), § 312.3(a) (only the legend appropriate for...

  19. 9 CFR 317.3 - Approval of abbreviations of marks of inspection; preparation of marking devices bearing...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... marking device containing any official mark or simulation thereof, or any label bearing any such mark or simulation, without the written authority therefor of the Administrator. However, when any such sample label... inspection legend, or simulation thereof, shown in § 312.2(a), § 312.3(a) (only the legend appropriate for...

  20. 9 CFR 317.3 - Approval of abbreviations of marks of inspection; preparation of marking devices bearing...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... marking device containing any official mark or simulation thereof, or any label bearing any such mark or simulation, without the written authority therefor of the Administrator. However, when any such sample label... inspection legend, or simulation thereof, shown in § 312.2(a), § 312.3(a) (only the legend appropriate for...

  1. Use of hemodialysis in meprobamate overdosage.

    PubMed

    Lobo, P I; Spyker, D; Surratt, P; Westervelt, F B

    1977-02-01

    A case of meprobamate overdosage successfully treated with hemodialysis is described. The patient was admitted 4 hours after an overdosage of meprobamate (30-40 g) deeply unconscious, hypotensive, in respiratory failure and with a serum meprobamate level of 50 mg/100 ml. Hemodialysis was instituted using a Gambro parallel flow dialyzer and a portable re-circulating dialyzate delivery system (Redy, CCi Life Systems). Meprobamate removal with hemodialysis was 672+/-167 mg/hr with a corresponding clearance of 61.97+/-9.9 ml/min. Drug removal with forced diuresis was 177+/-23.4 mg/hr. Metabolic degradation of the drug was approximately 482 mg/hr with a plasma disappearance rate of 5.2%/hr. No drug could be detected in the dialyzate fluid after its passage through the Redy re-circulating dialyzate system. Because of the rapidity of metabolic degradation of meprobamate, we feel that hemodialysis should be reserved for severe clinical intoxication and either compromised normal excretory routes or progressive clinical deterioration.

  2. Pyridostigmine treatment trial in neurogenic orthostatic hypotension.

    PubMed

    Singer, Wolfgang; Sandroni, Paola; Opfer-Gehrking, Tonette L; Suarez, Guillermo A; Klein, Caroline M; Hines, Stacy; O'Brien, Peter C; Slezak, Jeffrey; Low, Phillip A

    2006-04-01

    Midodrine hydrochloride is the only drug demonstrated in a placebo-controlled treatment trial to improve orthostatic hypotension (OH) but it significantly worsens supine hypertension. By enhancing ganglionic transmission, pyridostigmine bromide can potentially ameliorate OH without worsening supine hypertension. To evaluate the efficacy of a single 60-mg dose of pyridostigmine bromide, alone or in combination with a subthreshold (2.5 mg) or suprathreshold (5 mg) dose of midodrine hydrochloride, compared with placebo. We report a double-blind, randomized, 4-way cross-over study of pyridostigmine in the treatment of neurogenic OH. A total of 58 patients with neurogenic OH were enrolled. After 1 day of baseline measurements, patients were given 4 treatments (3 active treatments [60 mg of pyridostigmine bromide; 60 mg of pyridostigmine bromide and 2.5 mg of midodrine hydrochloride; 60 mg of pyridostigmine bromide and 5 mg of midodrine hydrochloride] and a placebo) in random order on successive days. Blood pressure (BP) and heart rate were measured, both supine and standing, immediately before treatment and hourly for 6 hours after the treatment was given. No significant differences were seen in the supine BP, either systolic (P = .36) or diastolic (P = .85). In contrast, the primary end point of the fall in standing diastolic BP was significantly reduced (P = .02) with treatment. Pairwise comparison showed significant reduction by pyridostigmine alone (BP fall of 27.6 mm Hg vs 34.0 mm Hg with placebo; P = .04) and pyridostigmine and 5 mg of midodrine hydrochloride (BP fall of 27.2 mm Hg vs 34.0 mm Hg with placebo; P = .002). Standing BP improvement significantly regressed with improvement in OH symptoms. Pyridostigmine significantly improves standing BP in patients with OH without worsening supine hypertension. The greatest effect is on diastolic BP, suggesting that the improvement is due to increased total peripheral resistance.

  3. 49 CFR 15.13 - Marking SSI.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Office of the Secretary of Transportation PROTECTION OF SENSITIVE SECURITY INFORMATION § 15.13 Marking... document. (b) Protective marking. The protective marking is: SENSITIVE SECURITY INFORMATION. (c... Sensitive Security Information that is controlled under 49 CFR parts 15 and 1520. No part of this record may...

  4. 49 CFR 15.13 - Marking SSI.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Office of the Secretary of Transportation PROTECTION OF SENSITIVE SECURITY INFORMATION § 15.13 Marking... document. (b) Protective marking. The protective marking is: SENSITIVE SECURITY INFORMATION. (c... Sensitive Security Information that is controlled under 49 CFR parts 15 and 1520. No part of this record may...

  5. 46 CFR 160.060-8 - Marking.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoyant Vest, Unicellular Polyethylene Foam, Adult and Child § 160.060-8 Marking. (a) Each buoyant vest must have the following information clearly... manufacturer or distributor). (Lot No.). (b) Waterproof marking. Marking of buoyant vests shall be sufficiently...

  6. 46 CFR 160.060-8 - Marking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoyant Vest, Unicellular Polyethylene Foam, Adult and Child § 160.060-8 Marking. (a) Each buoyant vest must have the following information clearly... manufacturer or distributor). (Lot No.). (b) Waterproof marking. Marking of buoyant vests shall be sufficiently...

  7. 46 CFR 160.060-8 - Marking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoyant Vest, Unicellular Polyethylene Foam, Adult and Child § 160.060-8 Marking. (a) Each buoyant vest must have the following information clearly... manufacturer or distributor). (Lot No.). (b) Waterproof marking. Marking of buoyant vests shall be sufficiently...

  8. Evaluation of pavement marking performance.

    DOT National Transportation Integrated Search

    2008-06-01

    The objective of the investigation was to evaluate the useful life of pavement markings. The Manual on Uniform Traffic Control Devices (MUTCD) provides general guidelines for the application and installation of pavement markings. However, performance...

  9. 49 CFR 180.515 - Markings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Pressure converted tank cars must have the new specification and conversion date permanently marked in... the manway nozzle flange on the left side of the car. The marking may have the last numeral of the...

  10. Prospective, randomized study of one, two, or three trabecular bypass stents in open-angle glaucoma subjects on topical hypotensive medication

    PubMed Central

    Katz, L Jay; Erb, Carl; Carceller, Guillamet Amadeu; Fea, Antonio M; Voskanyan, Lilit; Wells, Jeffrey M; Giamporcaro, Jane Ellen

    2015-01-01

    Purpose To assess the safety and efficacy of one, two, or three trabecular microbypass stents in eyes with primary open-angle glaucoma (OAG) not controlled on ocular hypotensive medication. A total of 119 subjects were followed for 18 months postoperatively. Materials and methods Subjects with medicated intraocular pressure (IOP) 18–30 mmHg and postmedication-washout baseline IOP 22–38 mmHg were randomized to implantation of one, two, or three stents. Ocular hypotensive medication was to be used if postoperative IOP exceeded 18 mmHg. Results A total of 38 subjects were implanted with one stent, 41 subjects with two stents, and 40 subjects with three stents. Both month 12 IOP reduction ≥20% without ocular hypotensive medication vs baseline unmedicated IOP and month 12 unmedicated IOP ≤18 mmHg were achieved by 89.2%, 90.2%, and 92.1% of one-, two-, and three-stent eyes, respectively. Furthermore, 64.9%, 85.4%, and 92.1% of the three respective groups achieved unmedicated IOP ≤15 mmHg. Over the 18-month follow-up period, medication was required in seven one-stent subjects, four two-stent subjects, and three three-stent subjects. At 18 months, mean unmedicated IOP was 15.9±0.9 mmHg in one-stent subjects, 14.1±1.0 mmHg in two-stent subjects, and 12.2±1.1 mmHg in three-stent subjects. Month 18 IOP reduction was significantly greater (P<0.001) with implantation of each additional stent, with mean differences in reduction of 1.84 mmHg (95% confidence interval 0.96–2.73) for three-stent vs two-stent groups and 1.73 mmHg (95% confidence interval 0.83–2.64) for two-stent vs one-stent groups. Adverse events through 18 months were limited to cataract progression with best-corrected visual acuity loss and subsequent cataract surgery. Conclusion In this series, implantation of each additional stent resulted in significantly greater IOP reduction with reduced medication use. Titratability of stents as a sole procedure was shown to be effective and safe, with

  11. [Effects of the renal blood flow at different levels by transcutaneous electrical acupoint stimulation combined general anesthesia induced controlled hypotension].

    PubMed

    Fang, Jian-Qiao; Zhang, Le-Le; Shao, Xiao-Mei

    2012-11-01

    To observe the intervention of transcutaneous electrical acupoint stimulation (TEAS) on the renal blood flow at different levels of mean arterial pressure (MAP) in controlled hypotension. Forty-two male beagle dogs were randomly divided into seven groups, i. e., the general anesthesia group, the 50% controlled group, the 40% controlled group, the 30% controlled group, the 50% experimental group, the 40% experimental group, and the 30% experimental group, 6 in each group. Beagles in the general anesthesia group were not treated with controlled hypotension, and the target MAP was achieved in those of the rest groups and maintained for 60 min. In the experimental groups, TEAS was applied to bilateral Hegu (LI4), Zusanli (ST36), Sanyinjiao (SP6), and Quchi (LI11) at 2/100 Hz with the stimulation strength of (4 +/- 1) mA starting from the stability of their physiological conditions to 60 min of maintaining the target MAP level. The changes of the renal blood flow were monitored at different time points using laser Doppler. From starting pressure control to the target MAP level, the renal blood flow was significantly lower in the 30% controlled group than in the general anesthesia group and the basic level of the same group (P < 0.05), while there was no obvious change in the 30% experimental group. In maintaining the blood pressure, the renal blood flow was significantly lower in the 50% controlled group, the 40% controlled group, the 30% controlled group, and the 30% experimental group than in the general anesthesia group (P < 0.05), while there was no obvious change in the 50% experimental group or the 40% experimental group. By the end of blood pressure recovery, the renal blood flow restored to the basic level in the 50% controlled group, the 50% experimental group, and the 40% experimental group (P > 0.05), while it was not restored to the basic level in the 40% controlled group, the 30% controlled group, and the 30% experimental group (P < 0.05). TEAS combined

  12. Marking Student Programs Using Graph Similarity

    ERIC Educational Resources Information Center

    Naude, Kevin A.; Greyling, Jean H.; Vogts, Dieter

    2010-01-01

    We present a novel approach to the automated marking of student programming assignments. Our technique quantifies the structural similarity between unmarked student submissions and marked solutions, and is the basis by which we assign marks. This is accomplished through an efficient novel graph similarity measure ("AssignSim"). Our experiments…

  13. 14 CFR 27.1555 - Control markings.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Control markings. (a) Each cockpit control, other than primary flight controls or control whose function... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Control markings. 27.1555 Section 27.1555... fuel controls— (1) Each fuel tank selector control must be marked to indicate the position...

  14. 14 CFR 27.1555 - Control markings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Control markings. (a) Each cockpit control, other than primary flight controls or control whose function... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Control markings. 27.1555 Section 27.1555... fuel controls— (1) Each fuel tank selector control must be marked to indicate the position...

  15. 14 CFR 27.1555 - Control markings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Control markings. (a) Each cockpit control, other than primary flight controls or control whose function... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Control markings. 27.1555 Section 27.1555... fuel controls— (1) Each fuel tank selector control must be marked to indicate the position...

  16. 14 CFR 27.1555 - Control markings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Control markings. (a) Each cockpit control, other than primary flight controls or control whose function... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Control markings. 27.1555 Section 27.1555... fuel controls— (1) Each fuel tank selector control must be marked to indicate the position...

  17. 14 CFR 27.1555 - Control markings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Control markings. 27.1555 Section 27.1555... Control markings. (a) Each cockpit control, other than primary flight controls or control whose function... fuel controls— (1) Each fuel tank selector control must be marked to indicate the position...

  18. Treatment of erectile dysfunction with sildenafil citrate (Viagra) in parkinsonism due to Parkinson's disease or multiple system atrophy with observations on orthostatic hypotension

    PubMed Central

    Hussain, I; Brady, C; Swinn, M; Mathias, C; Fowler, C

    2001-01-01

    OBJECTIVES—To assess the efficacy and safety of sildenafil citrate (Viagra) in men with erectile dysfunction and parkinsonism due either to Parkinson's disease or multiple system atrophy.
METHODS—Twenty four patients with erectile disease were recruited, 12 with Parkinson's disease and 12 with multiple system atrophy, into a randomised, double blind, placebo controlled, crossover study of sildenafil citrate. The starting dose was 50 mg active or placebo medication with the opportunity for dose adjustment depending on efficacy and tolerability. The international index of erectile function questionnaire (IIEF) was used to assess treatment efficacy and a quality of life questionnaire to assess the effect of treatment on sex life and whole life. Criteria for entry included a definite neurological diagnosis and a standing systolic blood pressure of 90-180 mm Hg and diastolic blood pressure of 50-110 mm Hg, on treatment if necessary. Blood pressure was taken at randomisation (visit 2) and crossover (visit 5) lying, sitting, and standing, before and 1 hour after taking the study medication in hospital.
RESULTS—Sidenafil citrate was efficacious in men with parkinsonism with a significant improvement, as demonstrated in questionnaire responses, in ability to achieve and maintain an erection and improvement in quality of sex life. In Parkinson's disease there was minimal change in blood pressure between active and placebo medication. In multiple system atrophy, six patients were studied before recruitment was stopped because three men showed a severe drop in blood pressure 1 hour after taking the active medication. Two were already known to have orthostatic hypotension and were receiving treatment with ephedrine and midodrine but the third had asymptomatic hypotension. However, the blood pressures in all three had been within the inclusion criterion for the study protocol. Despite a significant postural fall in blood pressure after sildenafil, all patients with

  19. Osmotic diuresis

    MedlinePlus

    ... disorders. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 125. Review Date 8/22/2016 Updated by: Laura J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine ...

  20. Mark IVA microprocessor support

    NASA Technical Reports Server (NTRS)

    Burford, A. L.

    1982-01-01

    The requirements and plans for the maintenance support of microprocessor-based controllers in the Deep Space Network Mark IVA System are discussed. Additional new interfaces and 16-bit processors have introduced problems not present in the Mark III System. The need for continuous training of maintenance personnel to maintain a level of expertise consistent with the sophistication of the required tools is also emphasized.

  1. 14 CFR 45.11 - Marking of products.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT IDENTIFICATION AND REGISTRATION MARKING Marking of Products and Articles § 45.11 Marking of products. (a) Aircraft. A manufacturer of aircraft covered under § 21.182 of this chapter must mark each aircraft by attaching a...

  2. 14 CFR 45.11 - Marking of products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT IDENTIFICATION AND REGISTRATION MARKING Marking of Products and Articles § 45.11 Marking of products. (a) Aircraft. A manufacturer of aircraft covered under § 21.182 of this chapter must mark each aircraft by attaching a...

  3. 14 CFR 45.11 - Marking of products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT IDENTIFICATION AND REGISTRATION MARKING Marking of Products and Articles § 45.11 Marking of products. (a) Aircraft. A manufacturer of aircraft covered under § 21.182 of this chapter must mark each aircraft by attaching a...

  4. 14 CFR 29.1555 - Control markings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....1555 Control markings. (a) Each cockpit control, other than primary flight controls or control whose... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Control markings. 29.1555 Section 29.1555... fuel controls— (1) Each fuel tank selector valve control must be marked to indicate the position...

  5. 14 CFR 29.1555 - Control markings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....1555 Control markings. (a) Each cockpit control, other than primary flight controls or control whose... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Control markings. 29.1555 Section 29.1555... fuel controls— (1) Each fuel tank selector valve control must be marked to indicate the position...

  6. 14 CFR 29.1555 - Control markings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....1555 Control markings. (a) Each cockpit control, other than primary flight controls or control whose... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Control markings. 29.1555 Section 29.1555... fuel controls— (1) Each fuel tank selector valve control must be marked to indicate the position...

  7. 14 CFR 29.1555 - Control markings.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....1555 Control markings. (a) Each cockpit control, other than primary flight controls or control whose... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Control markings. 29.1555 Section 29.1555... fuel controls— (1) Each fuel tank selector valve control must be marked to indicate the position...

  8. 14 CFR 29.1555 - Control markings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....1555 Control markings. (a) Each cockpit control, other than primary flight controls or control whose... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Control markings. 29.1555 Section 29.1555... fuel controls— (1) Each fuel tank selector valve control must be marked to indicate the position...

  9. 46 CFR 122.602 - Hull markings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hull markings. 122.602 Section 122.602 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE THAN 150....602 Hull markings. (a) Each vessel must be marked as required by part 67, subpart I, of this chapter...

  10. High contrast laser marking of alumina

    NASA Astrophysics Data System (ADS)

    Penide, J.; Quintero, F.; Riveiro, A.; Fernández, A.; del Val, J.; Comesaña, R.; Lusquiños, F.; Pou, J.

    2015-05-01

    Alumina serves as raw material for a broad range of advanced ceramic products. These elements should usually be identified by some characters or symbols printed directly on them. In this sense, laser marking is an efficient, reliable and widely implemented process in industry. However, laser marking of alumina still leads to poor results since the process is not able to produce a dark mark, yielding bad contrast. In this paper, we present an experimental study on the process of marking alumina by three different lasers working in two wavelengths: 1064 nm (Near-infrared) and 532 nm (visible, green radiation). A colorimetric analysis has been carried out in order to compare the resulting marks and its contrast. The most suitable laser operating conditions were also defined and are reported here. Moreover, the physical process of marking by NIR lasers is discussed in detail. Field Emission Scanning Electron Microscopy, High Resolution Transmission Electron Microscopy and X-ray Photoelectron Spectroscopy were also employed to analyze the results. Finally, we propose an explanation for the differences of the coloration induced under different atmospheres and laser parameters. We concluded that the atmosphere is the key parameter, being the inert one the best choice to produce the darkest marks.

  11. 46 CFR 111.25-5 - Marking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Marking. 111.25-5 Section 111.25-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Motors § 111.25-5 Marking. (a) Each motor must have a marking or nameplate that meets either Section 430...

  12. 46 CFR 111.25-5 - Marking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Marking. 111.25-5 Section 111.25-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Motors § 111.25-5 Marking. (a) Each motor must have a marking or nameplate that meets either Section 430...

  13. 46 CFR 111.25-5 - Marking.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Marking. 111.25-5 Section 111.25-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Motors § 111.25-5 Marking. (a) Each motor must have a marking or nameplate that meets either Section 430...

  14. 46 CFR 111.25-5 - Marking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Marking. 111.25-5 Section 111.25-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Motors § 111.25-5 Marking. (a) Each motor must have a marking or nameplate that meets either Section 430...

  15. 46 CFR 111.25-5 - Marking.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Marking. 111.25-5 Section 111.25-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Motors § 111.25-5 Marking. (a) Each motor must have a marking or nameplate that meets either Section 430...

  16. 27 CFR 28.123 - Export marks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Export marks. 28.123..., or Transportation to a Manufacturing Bonded Warehouse § 28.123 Export marks. (a) General. In addition... filled under the provisions of part 24 of this chapter, the proprietor shall mark the word “Export” on...

  17. Recent advances in orthostatic hypotension presenting orthostatic dizziness or vertigo.

    PubMed

    Kim, Hyun-Ah; Yi, Hyon-Ah; Lee, Hyung

    2015-11-01

    Orthostatic hypotension (OH), a proxy for sympathetic adrenergic failure, is the most incapacitating sign of autonomic failure. Orthostatic dizziness (OD) is known to be the most common symptom of OH. However, recent studies have demonstrated that 30-39 % of patients with OH experienced rotatory vertigo during upright posture (i.e., orthostatic vertigo, OV), which challenges the dogma that OH induces dizziness and not vertigo. A recent population-based study on spontaneously occurring OD across a wide age range showed that the one-year and lifetime prevalence of OD was 10.9 and 12.5 %, respectively. Approximately 83 % of patients with OD had at least one abnormal autonomic function test result. So far, 11 subtypes of OD have been proposed according to the pattern of autonomic dysfunction, and generalized autonomic failure of sympathetic adrenergic and parasympathetic cardiovagal functions was the most common type. Four different patterns of OH, such as classic, delayed, early, and transient type have been found in patients with OD. The head-up tilt test and Valsalva maneuver should be performed for a comprehensive evaluation of sympathetic adrenergic failure in patients with OD/OV. This review summarizes current advances in OH presenting OD/OV, with a particular focus on the autonomic dysfunction associated with OD.

  18. 14 CFR 25.1555 - Control markings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....1555 Control markings. (a) Each cockpit control, other than primary flight controls and controls whose... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Control markings. 25.1555 Section 25.1555... aerodynamic control must be marked under the requirements of §§ 25.677 and 25.699. (c) For powerplant fuel...

  19. 14 CFR 25.1555 - Control markings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....1555 Control markings. (a) Each cockpit control, other than primary flight controls and controls whose... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Control markings. 25.1555 Section 25.1555... aerodynamic control must be marked under the requirements of §§ 25.677 and 25.699. (c) For powerplant fuel...

  20. 14 CFR 25.1555 - Control markings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....1555 Control markings. (a) Each cockpit control, other than primary flight controls and controls whose... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Control markings. 25.1555 Section 25.1555... aerodynamic control must be marked under the requirements of §§ 25.677 and 25.699. (c) For powerplant fuel...

  1. 27 CFR 28.223 - Export marks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Export marks. 28.223... Export marks. In addition to the marks and brands required to be placed on kegs, barrels, cases, crates... “Export” on each container or case before removal for export, for use on vessels or aircraft, or for...

  2. 40 CFR 761.45 - Marking formats.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... POLYCHLORINATED BIPHENYLS (PCBs) MANUFACTURING, PROCESSING, DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Marking...) Large PCB Mark—M L. Mark ML shall be as shown in Figure 1, letters and striping on a white or yellow... PCB Mark—M s. Mark Ms shall be as shown in Figure 2, letters and striping on a white or yellow...

  3. 14 CFR 23.1555 - Control markings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Control markings. 23.1555 Section 23.1555... Markings and Placards § 23.1555 Control markings. Link to an amendment published at 76 FR 75763, December 2, 2011. (a) Each cockpit control, other than primary flight controls and simple push button type starter...

  4. 14 CFR 25.1555 - Control markings.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Control markings. 25.1555 Section 25.1555....1555 Control markings. (a) Each cockpit control, other than primary flight controls and controls whose... aerodynamic control must be marked under the requirements of §§ 25.677 and 25.699. (c) For powerplant fuel...

  5. 14 CFR 25.1555 - Control markings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Control markings. 25.1555 Section 25.1555....1555 Control markings. (a) Each cockpit control, other than primary flight controls and controls whose... aerodynamic control must be marked under the requirements of §§ 25.677 and 25.699. (c) For powerplant fuel...

  6. 46 CFR 97.40-5 - Hull markings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hull markings. 97.40-5 Section 97.40-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS OPERATIONS Markings on Vessels § 97.40-5 Hull markings. Vessels shall be marked as required by parts 67 and 69 of this...

  7. 46 CFR 196.40-5 - Hull markings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Hull markings. 196.40-5 Section 196.40-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS OPERATIONS Markings on Vessels § 196.40-5 Hull markings. Vessels shall be marked as required by parts 67 and 69 of this chapter...

  8. 46 CFR 78.50-5 - Hull markings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Hull markings. 78.50-5 Section 78.50-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS OPERATIONS Markings on Vessels § 78.50-5 Hull markings. Vessels shall be marked as required by parts 67 and 69 of this chapter. [CGD 72...

  9. Post-exercise hypotension and heart rate variability response after water- and land-ergometry exercise in hypertensive patients

    PubMed Central

    Bocalini, Danilo Sales; Bergamin, Marco; Evangelista, Alexandre Lopes; Rica, Roberta Luksevicius; Pontes, Francisco Luciano; Figueira, Aylton; Serra, Andrey Jorge; Rossi, Emilly Martinelli; Tucci, Paulo José Ferreira

    2017-01-01

    Background systemic arterial hypertension is the most prevalent cardiovascular disease; physical activity for hypertensive patients is related to several beneficial cardiovascular adaptations. This paper evaluated the effect of water- and land-ergometry exercise sessions on post-exercise hypotension (PEH) of healthy normotensive subjects versus treated or untreated hypertensive patients. Methods Forty-five older women composed three experimental groups: normotensive (N, n = 10), treated hypertensive (TH, n = 15) and untreated hypertensive (UH, n = 20). The physical exercise acute session protocol was performed at 75% of maximum oxygen consumption (VO2max) for 45 minutes; systolic (SBP), diastolic (DBP) and mean (MBP) blood pressure were evaluated at rest, peak and at 15, 30, 45, 60, 75 and 90 minutes after exercise cessation. Additionally, the heart rate variability (HRV) was analyzed by R-R intervals in the frequency domain for the assessment of cardiac autonomic function. Results In both exercise modalities, equivalent increases in SBP were observed from rest to peak exercise for all groups, and during recovery, significant PEH was noted. At 90 minutes after the exercise session, the prevalence of hypotension was significantly higher in water- than in the land-based protocol. Moreover, more pronounced reductions in SBP and DBP were observed in the UH patients compared to TH and N subjects. Finally, exercise in the water was more effective in restoring HRV during recovery, with greater effects in the untreated hypertensive group. Conclusion Our data demonstrated that water-ergometry exercise was able to induce expressive PEH and improve cardiac autonomic modulation in older normotensive, hypertensive treated or hypertensive untreated subjects when compared to conventional land-ergometry. PMID:28658266

  10. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Safe water marks. 62.27 Section... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is navigable water all around the mark. They are often used to indicate...

  11. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Safe water marks. 62.27 Section... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is navigable water all around the mark. They are often used to indicate...

  12. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Safe water marks. 62.27 Section... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is navigable water all around the mark. They are often used to indicate...

  13. A Comparative Evaluation of Analytical Methods to Allocate Individual Marks from a Team Mark

    ERIC Educational Resources Information Center

    Nepal, Kali

    2012-01-01

    This study presents a comparative evaluation of analytical methods to allocate individual marks from a team mark. Only the methods that use or can be converted into some form of mathematical equations are analysed. Some of these methods focus primarily on the assessment of the quality of teamwork product (product assessment) while the others put…

  14. Hypotensive Effect and Accumulation of Dinitrosyl Iron Complexes in Blood and Tissues after Intravenous and Subcutaneous Injection.

    PubMed

    Timoshin, A A; Lakomkin, V L; Abramov, A A; Ruuge, E K; Vanin, A F

    2016-12-01

    Subcutaneous injection of Oxacom with glutathione-bound dinitrosyl iron complex as the active principle produced a slower drop of mean BP and longer accumulation of protein-bound dinitrosyl iron complexes in whole blood and tissues than intravenous injection of this drug, while durations of hypotensive effect in both cases were practically identical. In contrast to intravenous injection of the drug, its subcutaneous administration was not characterized by a high concentration of protein-bound dinitrosyl iron complexes in the blood at the onset of experiment; in addition, accumulation of these NO forms in the lungs was more pronounced after subcutaneous injection than after intravenous one.

  15. Nitroglycerin hypotensive effect and application in a combined surgery for reconstruction after ipsilateral maxillectomy and orbit evisceration.

    PubMed

    Sun, Yuhang; Dong, Xiaohui; Zhang, Guofeng; An, Jing; Yuan, Haojun

    2017-05-01

    The oral and maxillofacial region is rich in blood, and it is often difficult to stop bleeding during the operation of maxilla. Nitroglycerin is one of the most commonly used antihypertensive drugs in our hospital. We observed the effect of controlled hypotension in patients with maxillary resection. In group N, the patients had different degrees of tachycardia after using nitroglycerin only. In addition, nitroglycerin has the characteristics of rapid drug resistance. A combined reversed temporal muscle flap and random forehead flap technique was performed successfully to reconstruct the large defect after ipsilateral maxillectomy and orbit evisceration. There were 43 cases used this method during 2014-2016 without large side effects.

  16. 22 CFR 226.91 - Marking.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., public communications, and commodities, specified further at paragraph (b)-(e) of this section, partially... funded public communications and program materials for compliance with the approved Marking Plan. (3... marked with the USAID Identity. (1) Any “public communications” as defined in § 226.2, funded by USAID...

  17. 22 CFR 226.91 - Marking.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., public communications, and commodities, specified further at paragraph (b)-(e) of this section, partially... funded public communications and program materials for compliance with the approved Marking Plan. (3... marked with the USAID Identity. (1) Any “public communications” as defined in § 226.2, funded by USAID...

  18. A 33-year-old white female with abdominal pain, nausea, vomiting and hypotension.

    PubMed

    Westfall, M D; Lumpkin, J

    1993-01-01

    A thirty-three year old female presented to our emergency department complaining of severe abdominal pain, nausea, and vomiting. On physical examination she was hypotensive with a firm, tender abdomen, cervical motion tenderness and a diffuse erythematous rash. A surgical diagnosis of Acute Pelvic Inflammatory Disease was made during laparoscopy. Coagulant studies, liver function tests, culture results, and the desquamation of the patient's palms led to the additional diagnosis of Toxic Shock Syndrome. A literature search failed to reveal any similar cases of Pelvic Inflammatory Disease (PID) and Toxic Shock Syndrome (TSS) occurring concomitantly. Patients may present severely ill with either of these disease entities but potential for serious illness is greater when both of these syndromes occur in the same patient. We conclude that in patients with a similar presentation, the symptoms should not be attributed completely to PID without further investigation and consideration of a concomitant disease process including TSS.

  19. Prevention of hypotension and prolongation of postoperative analgesia in emergency cesarean sections: A randomized study with intrathecal clonidine

    PubMed Central

    Bajwa, Sukhminder Jit Singh; Bajwa, Sukhwinder Kaur; Kaur, Jasbir; Singh, Amarjit; Singh, Anita; Parmar, Surjit Singh

    2012-01-01

    Background and Context: Different adjuvants been tried out for neuraxial anesthesia in emergency caesarean section so that the dose of the local anesthetic can be reduced and hypotension thereby prevented. Aims and Objectives: The present study was carried out in patients presenting for emergency lower segment caesarean section (LSCS) to establish the dose of intrathecal clonidine that would allow reduction of the dose of local anesthetic (thereby reducing the incidence and magnitude of hypotension) while at the same time providing clinically relevant prolongation of spinal anesthesia without significant side effects. Materials and Methods: This randomized clinical study was carried out in our institution among 100 pregnant females who underwent emergency caesarean section. The participants were divided randomly into four groups: A, B, C, and D, each comprising 25 parturients. Subarachnoid block was performed using a 26G Quincke needle, with 12 mg of hyperbaric bupivacaine (LA) in group A, 9 mg of LA + 30 μg of clonidine in group B, LA + 37.5 μg of clonidine in group C, and LA + 45 μg of clonidine in group D. The solution was uniformly made up to 2.2 mL with normal saline in all the groups. Onset of analgesia at T10 level, sensory and motor blockade levels, maternal heart rate and blood pressure, neonatal Apgar scores, postoperative block characteristics, and adverse events were looked for and recorded. Statistical analysis was carried out with SPSS® version 10.0 for Windows®, using the ANOVA test with post hoc significance, the Chi-square test, and the Mann-Whitney U test. P<.05 was considered significant and P<.0001 as highly significant. Results: One hundred patients were enrolled for this study. The four groups were comparable with regard to demographic data and neonatal Apgar scores. Onset and establishment of sensory and motor analgesia was significantly shorter in groups C and D, while hypotension (and the use of vasopressors) was significantly higher

  20. Autoregulation of cerebral blood flow in orthostatic hypotension

    NASA Technical Reports Server (NTRS)

    Novak, V.; Novak, P.; Spies, J. M.; Low, P. A.

    1998-01-01

    BACKGROUND AND PURPOSE: We sought to evaluate cerebral autoregulation in patients with orthostatic hypotension (OH). METHODS: We studied 21 patients (aged 52 to 78 years) with neurogenic OH during 80 degrees head-up tilt. Blood flow velocities (BFV) from the middle cerebral artery were continuously monitored with transcranial Doppler sonography, as were heart rate, blood pressure (BP), cardiac output, stroke volume, CO2, total peripheral resistance, and cerebrovascular resistance. RESULTS: All OH patients had lower BP (P<.0001), BFV_diastolic (P<.05), CVR (P<.007), and TPR (P<.02) during head-up tilt than control subjects. In control subjects, no correlations between BFV and BP were found during head-up tilt, suggesting normal autoregulation. OH patients could be separated into those with normal or expanded autoregulation (OH_NA; n=16) and those with autoregulatory failure (OH_AF; n=5). The OH_NA group showed either no correlation between BFV and BP (n=8) or had a positive BFV/BP correlation (R2>.75) but with a flat slope. An expansion of the "autoregulated" range was seen in some patients. The OH_AF group was characterized by a profound fall in BFV in response to a small reduction in BP (mean deltaBP <40 mm Hg; R2>.75). CONCLUSIONS: The most common patterns of cerebral response to OH are autoregulatory failure with a flat flow-pressure relationship or intact autoregulation with an expanded autoregulated range. The least common pattern is autoregulatory failure with a steep flow-pressure relationship. Patients with patterns 1 and 2 have an enhanced capacity to cope with OH, while those with pattern 3 have reduced capacity.