Impulse oscillometry: a measure for airway obstruction.

PubMed

Vink, Geraldine R; Arets, Hubertus G M; van der Laag, Johan; van der Ent, Cornelis K

2003-03-01

The impulse oscillometry system (IOS) was introduced as a new technique to assess airflow obstruction in patients who are not able to perform forced breathing maneuvers, e.g., subjects with cerebral palsy or severe mental retardation, and young children. This study evaluates the sensitivity and specificity of IOS parameters to quantify changes in airflow obstruction in comparison with forced expiratory volume in the first second (FEV(1)) and peak expiratory flow (PEF) measurements. Measurements of FEV(1), PEF, and resistance (R) and reactance (X) at frequencies of 5-35 Hz were performed in 19 children with asthma before, during, and after methacholine challenge and subsequent bronchodilatation. All parameters changed significantly during tests. Values of R5 and R10 correlated with FEV(1) (r = -0.71 and -0.73, respectively, P < 0.001), as did values of X5 and X10 (r = 0.52 and 0.57, respectively, P < 0.01). Changes in R preceded changes in PEF and FEV(1) during methacholine challenge. The area under the receiver operating characteristic (ROC) curve to predict a 15% fall in FEV(1) showed better sensitivity and specificity for R5 (area under the curve, 0.85) compared to PEF (0.79) or R10 (0.73). We conclude that IOS parameters can be easily used as an indirect measure of airflow obstruction. This might be helpful in patients who are not able to perform forced breathing maneuvers. In individual subjects, R values measured at 5 Hz showed to be superior to PEF measurements in the detection of a 15% fall in FEV(1). Copyright 2003 Wiley-Liss, Inc.

A computational model of the cardiovascular system coupled with an upper-arm oscillometric cuff and its application to studying the suprasystolic cuff oscillation wave, concerning its value in assessing arterial stiffness.

PubMed

Liang, Fuyou; Takagi, Shu; Himeno, Ryutaro; Liu, Hao

2013-01-01

A variety of methods have been proposed to noninvasively assess arterial stiffness using single or multiple oscillometric cuffs. A common pitfall of most of such methods is that the individual-specific accuracy of assessment is not clearly known due to an insufficient understanding of the relationships between the characteristics of cuff oscillometry and cardiovascular properties. To provide a tool for quantitatively investigating such relationships, we developed a computational model of the cardiovascular system coupled with an oscillometric cuff wrapped around the left upper arm. The model was first examined by simulating the inflation-deflation process of the cuff. The simulated results reasonably reproduced the well-established characteristics of cuff oscillometry. The model was then applied to study the oscillation wave generated by a suprasystolic cuff that is currently under considerable debate regarding its validity for assessing aortic stiffness. The simulated results confirmed the experimental observations that the suprasystolic cuff oscillation wave resembles the blood pressure wave in the proximal brachial artery and is characterised by the presence of two systolic peaks. A systemic analysis on the simulation results for various cardiovascular/physiological conditions revealed that neither the time lag nor the height difference between the two peaks is a direct indicator of aortic stiffness. These findings provided useful evidence for explaining the conflicts among previous studies. Finally, it was stressed that although the emphasis of this study has been placed on a suprasystolic upper-arm cuff, the model could be employed to address more issues related to oscillometric cuffs.

Sensitivity of newly defined impulse oscillometry indices in preschool children.

PubMed

Knihtilä, Hanna; Kotaniemi-Syrjänen, Anne; Pelkonen, Anna S; Kalliola, Satu; Mäkelä, Mika J; Malmberg, L Pekka

2017-05-01

Early origins of chronic obstructive pulmonary disease have been recognized. Impulse oscillometry (IOS) is suitable for assessment of lung function also in preschool children, and some novel indices have been connected to assessment of small airway function. However, limited data exist on the sensitivity of these new indices to detect lung function deficits in young symptomatic children. IOS measurements of 103 healthy preschool children were evaluated to establish reference equations for the difference between respiratory resistance at 5 and 20 Hz (R5-20), the relative difference of R5-20 (R5-20%), and area under the reactance curve (AX). Thereafter, IOS results of children with late-onset troublesome lung symptoms (n = 20), a history of early wheeze (n = 37), or a history of bronchopulmonary dysplasia (BPD, n = 8) were compared to healthy children. None of the patient groups differed from healthy regarding respiratory resistance at 5 Hz (R5), and only children with a history of BPD differed from healthy regarding respiratory reactance at 5 Hz (X5). In contrast, z-scores of R5-20, R5-20%, and AX were significantly higher in all patient groups than in healthy children (P < 0.001), showing improved sensitivity (20-55%) compared to R5 and X5 (5-6%). R5-20, R5-20%, and AX are superior to conventional IOS parameters in distinguishing children with current or past lower respiratory tract symptoms from healthy, and may prove valuable for screening early lung function deficits. Pediatr Pulmonol. 2017;52:598-605. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Systolic arterial blood pressure estimated by mitral regurgitation velocity, high definition oscillometry, and Doppler ultrasonography in dogs with naturally occurring degenerative mitral valve disease.

PubMed

Hanzlicek, A S; Baumwart, R D; Payton, M E

2016-09-01

To determine if systolic blood pressure estimated by mitral regurgitation (MR) velocity can be used interchangeably with that estimated by high definition oscillometry (HDO) and Doppler ultrasonography (DU) in dogs with naturally occurring mitral valve disease (MVD). Forty-nine client-owned dogs with naturally occurring MVD. This is a retrospective study. Medical records were reviewed and dogs with MR caused by degenerative MVD were included if systolic blood pressure was estimated from MR velocity determined by continuous wave Doppler (CW), DU and HDO at the same visit. A Pearson product moment correlation coefficient was determined for each combination of measures and tested for significance with a paired t-test. Limits of agreement between 2 measures were determined by the 95% confidence interval of the average difference of the means and illustrated by Bland-Altman plots. Systolic pressure estimated from CW was significantly but only moderately correlated to DU (r = 0.42, p=0.0015) and HDO (r = 0.40, p=0.0021). Pressure estimated from DU was significantly but only moderately correlated to HDO (r = 0.57, p≤0.0001). Limits of agreement were wide for all measures including DU and CW (-61.9to 44.6 mmHg), HDO and CW (-65.2to 26.9 mmHg), and HDO and DU (-63.1 to 42.06 mmHg). Systolic blood pressure estimated by CW cannot be used interchangeably with HDO or DU in dogs with naturally occurring MVD. Copyright © 2016 Elsevier B.V. All rights reserved.

Relating small airways to asthma control using impulse oscillometry in children

PubMed Central

Shi, Yixin; Aledia, Anna S.; Tatavoosian, Ahramahzd V.; Vijayalakshmi, Shruthi; Galant, Stanley P.; George, Steven C.

2012-01-01

Background Previous reports suggest that peripheral airways are associated with asthma control. Patient history, although subjective is used largely to assess asthma control in children because spirometry is many times normal. Impulse oscillometry (IOS) is an objective non-invasive measurement of lung function, which has the potential to examine independently both small and large airway obstruction. Objective To determine the utility of IOS in assessing asthma control in children. Methods Asthmatic and healthy children (6–17 yrs) were enrolled in the study. Spirometry and IOS (resistance at 5 and 20 Hz, R5 and R20, respectively, reactance at 5 Hz, X5, resonant frequency, Fres, and area under the reactance curve between 5 Hz and Fres, AX) were collected in triplicate before and after a bronchodilator was administered. The physicians were blinded to the IOS measurements and assessed asthma control using ATS guidelines. Results Small airway IOS measurements, including R5-20, X5, Fres and AX, of children with uncontrolled asthma (n=44) were significantly different from those of controlled asthmatic (n=57) and healthy (n=14) children, especially prior to the administration of a bronchodilator. However, there was no difference in large airway IOS (R20). No differences were found between controlled asthmatic and healthy children in any of the endpoints. ROC analysis showed cut-points for baseline R5-20 (1.5 cmH2O·L−1·s) and AX (9.5 cmH2O·L−1) that effectively discriminated controlled versus uncontrolled asthma (AUC=0.86 and 0.84), and correctly classified more than 80% of the population. Conclusion Uncontrolled asthma is associated with small airways dysfunction, and IOS may be a reliable non-invasive method to assess asthma control in children. PMID:22178635

Progress in high-dose radiation dosimetry. Final report

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

Ettinger, K.V.; Nam, J.W.; McLaughlin, W.L.

1981-01-01

The last decade has witnessed a deluge of new high-dose dosimetry techniques and expended applications of methods developed earlier. Many of the principal systems are calibrated by means of calorimetry, although production of heat is not always the final radiation effect of interest. Requirements for a stable and reliable transfer dose meters have led to further developments of several important high-dose systems: thermoluminescent materials, radiochromic dyes, ceric-cerous solutions analyzed by high-frequency oscillometry. A number of other prospective dosimeters are also treated in this review. In addition, an IAEA program of high-dose intercomparison and standardization for industrial radiation processing is described.

Progress in high-dose radiation dosimetry. Final report

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

Ettinger, K.V.; Nam, J.W.; McLaughlin, W.L.

1981-01-01

The last decade has witnessed a deluge of new high-dose dosimetry techniques and expended applications of methods developed earlier. Many of the principal systems are calibrated by means of calorimetry, although production of heat is not always the final radiation effect of interest. Requirements for a stable and reliable transfer dose meters have led to further developments of several important high-dose systems: thermoluminescent materials, radiochromic dyes, ceric-cerous solutions analyzed by high-frequency oscillometry. A number of other prospective dosimeters also treated in this review. In addition, an IAEA programme of high-dose intercomparison and standardization for industrial radiation processing is described.

Military Personnel Selection and Diagnostic Control of Human Functional State in High Altitude Conditions

DTIC Science & Technology

2001-06-01

individually authored sections f proceedings, annals, symposia, etc. However, the component should be considered within [he context of the overall compilation...data of oscillometry are: a) an increase of diastolic and mean arterial pressure AP no more than 10-15 mm of mercury pole (Hg); b) changing of...Ow- 00 oC "_ I 1.4C" >. U0 U U4 15-12 C14) 00 F -- Ci-0 toiL C) f Cuu 4;- 0CD C)C 5 0 cuc cdo 4! C)* 00 09 0 0- C=1 -4o 0 F - 8 - gCsC u 0 > 0 >o > 2- 0

Impulse oscillometry at preschool age is a strong predictor of lung function by flow-volume spirometry in adolescence.

PubMed

Lauhkonen, Eero; Riikonen, Riikka; Törmänen, Sari; Koponen, Petri; Nuolivirta, Kirsi; Helminen, Merja; Toikka, Jyri; Korppi, Matti

2018-05-01

The transition from early childhood wheezing to persistent asthma is linked to lung function impairment over time. Little is known how the methods used to study lung function at different ages correlate longitudinally. Sixty-four children with a history of hospitalization for bronchiolitis before 6 months of age were prospectively studied with impulse oscillometry (IOS) at the mean age of 6.3 years and these preschool IOS results were compared with flow-volume spirometry (FVS) measurements at mean age of 11.4 years. The baseline respiratory system resistance at 5 Hz (Rrs5) showed a modest statistically significant correlation with all baseline FVS parameters except FVC. The post-bronchodilator (post-BD) Rrs5 showed a modest statistically significant correlation with post-BD FEV 1 and FEV 1 /FVC. The bronchodilator-induced decrease in Rrs5 showed a modest statistically significant correlation with the percent increase in FEV 1 . Baseline and post-BD respiratory reactance at 5 Hz (Xrs5) showed a modest statistically significant correlation with baseline and post-BD FVS parameters except post-BD FEV 1 /FVC, respectively, and post-BD Xrs5 showed a strong correlation with post-BD FVC (ρ = 0.61) and post-BD FEV 1 (ρ = 0.59). In adjusted linear regression, preschool Xrs5 remained as a statistically significant independent predictor of FVS parameters in adolescence; the one-unit decrease in the Z-score of preschool post-BD Xrs5 predicted 9.6% lower post-BD FEV 1 , 9.3% lower post-BD FVC, and 9.7% lower post-BD MEF 50 when expressed as %-predicted parameters. Persistent post-BD small airway impairment in children with a history of bronchiolitis detected with IOS at preschool age predicted FVS results measured in early adolescence. © 2018 Wiley Periodicals, Inc.

High Central Aortic Rather than Brachial Blood Pressure is Associated with Carotid Wall Remodeling and Increased Arterial Stiffness in Childhood.

PubMed

Peluso, Gonzalo; García-Espinosa, Victoria; Curcio, Santiago; Marota, Marco; Castro, Juan; Chiesa, Pedro; Giachetto, Gustavo; Bia, Daniel; Zócalo, Yanina

2017-03-01

In adults, central blood pressure (cBP) is reported to associate target organ damages (TODs) rather than peripheral blood pressure (pBP). However, data regarding the association of pre-clinical TODs with cBP and pBP in pediatric populations are scarce. To evaluate in children and adolescents the importance of cBP and pBP levels, in terms of their association with hemodynamic and vascular changes. 315 subjects [age (mean/range) 12/8-18 years] were included. pBP (oscillometry, Omron-HEM433INT and Mobil-O-Graph), cBP levels and waveforms (oscillometry, Mobil-O-Graph; applanation tonometry, SphygmoCor), aortic wave reflection-related parameters, carotid intima-media thickness (CIMT) and carotid (elastic modulus, stiffness-index) and aortic stiffness (carotid-femoral pulse wave velocity, PWV). Four groups were defined considering pBP and cBP percentiles (th): cBP ≥90th, cBP <90th, pBP ≥90th, pBP <90th. In each group, haemodynamic and vascular parameters were compared for subgroups defined considering the level of the remaining blood pressure (cBP or pBP). Subgroups were matched for anthropometric and cardiovascular risk factors (propensity matching-score). Subjects with high cBP showed a worse cardiovascular risk profile in addition to worse peripheral hemodynamic conditions. The CIMT, carotid and aortic stiffness levels were also higher in those subjects. CIMT and carotid stiffness remained statistically higher when subjects were matched for pBP and other cardiovascular risk factors. There were no differences in arterial properties when subjects were analyzed (compared) considering similar pBP levels, during normal and high cBP conditions. Compared with pBP, the cBP levels show a greater association with vascular alterations (high CIMT and arterial stiffness), in children and adolescents.

Non-invasive pulmonary function test on Morquio Patients

PubMed Central

Kubaski, Francyne; Tomatsu, Shunji; Patel, Pravin; Shimada, Tsutomu; Xie, Li; Yasuda, Eriko; Mason, Robert; Mackenzie, William G.; Theroux, Mary; Bober, Michael B.; Oldham, Helen M.; Orii, Tadao; Shaffer, Thomas H.

2015-01-01

In clinical practice, respiratory function tests are difficult to perform in Morquio syndrome patients due to their characteristic skeletal dysplasia, small body size and lack of cooperation of young patients, where in some cases, conventional spirometry for pulmonary function is too challenging. To establish feasible clinical pulmonary endpoints and determine whether age impacts lung function in Morquio patients non-invasive pulmonary tests and conventional spirometry were evaluated. The non-invasive pulmonary tests: impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography in conjunction with conventional spirometry were evaluated in twenty-two Morquio patients (18 Morquio A and 4 Morquio B) (7 males), ranging from 3 and 40 years of age. Twenty-two patients were compliant with non-invasive tests (100%) with exception of IOS (81.8%–18 patients). Seventeen patients (77.3%) were compliant with spirometry testing. All subjects had normal vital signs at rest including > 95% oxygen saturation, end tidal CO2 (38–44 mmHg), and age-appropriate heart rate (mean=98.3, standard deviation=19) (two patients were deviated). All patients preserved normal values in impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography, although predicted forced expiratory volume total (72.8 ± 6.9 SE%) decreased with age and was below normal; phase angle (35.5 ± 16.5 Degrees), %Rib Cage (41.6 ± 12.7%), resonant frequency, and forced expiratory volume in one second/forced expiratory volume total (110.0 ± 3.2 SE%) were normal and not significantly impacted by age. The proposed non-invasive pulmonary function tests are able to cover a greater number of patients (young patients and/or wheel-chair bound), thus providing a new diagnostic approach for the assessment of lung function in Morquio syndrome which in many cases may be difficult to evaluate. Morquio patients studied herein demonstrated no clinical or functional signs of restrictive and/or obstructive lung disease. PMID:26116954

Application of impulse oscillometry and bronchial dilation test for analysis in patients with asthma and chronic obstructive pulmonary disease

PubMed Central

Li, Yueyue; Chen, Yang; Wang, Ping

2015-01-01

Impulse oscillometry (IOS) is a good method for measuring airway resistance. The aim of this study was to assess the diagnostic contribution of IOS combined with bronchial dilation test (BDT) when distinguishing between patients with asthma and those with chronic obstructive pulmonary disease (COPD). 870 were enrolled in the study including 561 patients with asthma, 100 patients with COPD and 209 patients with chronic coughing or normal subjects. All the participants underwent routine pulmonary function tests, IOS and BDT examination. And IOS examination was before and after BDT. IOS parameters (R5, R20, R25, R35, X5, X20, X25, X35, Fres, Zrs & RP) and forced expiratory volume in one second (FEV1) were recorded. Receiver operating characteristics (ROC) curve analysis was performed to evaluate the diagnostic ability to differentiate asthma and COPD. The discriminative power of the various parameters studied was determined by means of ROC curves: the area under the curve (AUC), sensitivity and specificity. The X5, X20, X25, X35, Fres, Zrs and Rp correlated better with COPD. In particular, X5, Fres and X25 have been found to be significantly correlated with COPD. The diagnostic efficiency of X5, Fres and X25 when diagnosis COPD, expressed by ROC curve parameters, was as follows: AUC (0.725, 0.730, 0.724), sensitivity (67%, 77%, 83%) and specificity (68%, 65%, 58%), respectively. The diagnostic efficiency of Zrs, R5 and X35 when diagnosis asthma, expressed by ROC curve parameters, was as follows: AUC (0.721, 0.710, 0.695), sensitivity (62%, 72%, 53%) and specificity (72%, 61%, 76%), respectively. Our findings show, that X5, X25 and Fres may be useful for predictions and evaluations for COPD. And R5, X35 and Zrs may provide useful IOS parameters for asthma. IOS combined BDT could be useful diagnostic and differential diagnosis between asthma and COPD. PMID:25785124

Application of impulse oscillometry and bronchial dilation test for analysis in patients with asthma and chronic obstructive pulmonary disease.

PubMed

Li, Yueyue; Chen, Yang; Wang, Ping

2015-01-01

Impulse oscillometry (IOS) is a good method for measuring airway resistance. The aim of this study was to assess the diagnostic contribution of IOS combined with bronchial dilation test (BDT) when distinguishing between patients with asthma and those with chronic obstructive pulmonary disease (COPD). 870 were enrolled in the study including 561 patients with asthma, 100 patients with COPD and 209 patients with chronic coughing or normal subjects. All the participants underwent routine pulmonary function tests, IOS and BDT examination. And IOS examination was before and after BDT. IOS parameters (R5, R20, R25, R35, X5, X20, X25, X35, Fres, Zrs & RP) and forced expiratory volume in one second (FEV1) were recorded. Receiver operating characteristics (ROC) curve analysis was performed to evaluate the diagnostic ability to differentiate asthma and COPD. The discriminative power of the various parameters studied was determined by means of ROC curves: the area under the curve (AUC), sensitivity and specificity. The X5, X20, X25, X35, Fres, Zrs and Rp correlated better with COPD. In particular, X5, Fres and X25 have been found to be significantly correlated with COPD. The diagnostic efficiency of X5, Fres and X25 when diagnosis COPD, expressed by ROC curve parameters, was as follows: AUC (0.725, 0.730, 0.724), sensitivity (67%, 77%, 83%) and specificity (68%, 65%, 58%), respectively. The diagnostic efficiency of Zrs, R5 and X35 when diagnosis asthma, expressed by ROC curve parameters, was as follows: AUC (0.721, 0.710, 0.695), sensitivity (62%, 72%, 53%) and specificity (72%, 61%, 76%), respectively. Our findings show, that X5, X25 and Fres may be useful for predictions and evaluations for COPD. And R5, X35 and Zrs may provide useful IOS parameters for asthma. IOS combined BDT could be useful diagnostic and differential diagnosis between asthma and COPD.

Asymptomatic tracheal MALT lymphoma discovered on spirometric findings presenting with elevated respiratory resistance.

PubMed

Kadota, Naoki; Shinohara, Tsutomu; Machida, Hisanori; Nakanishi, Hirofumi; Suehiro, Fumie; Toda, Hiroko; Yoshino, Tadashi; Ogushi, Fumitaka

2015-06-06

Central airway obstruction (CAO) may be caused by various etiologies. However, conventional chest X-rays are rarely diagnostic for patients with CAO. We here described a 64-year-old asymptomatic female with tracheal mucosa-associated lymphoid tissue lymphoma discovered on spirometric findings during a complete physical examination. The plateau of forced expiratory flow was consistent with CAO. A decreased peak expiratory flow rate was noted at least 3 years before the diagnosis, and was attributed to an insufficient effort by the patient. Impulse oscillometric measurements, which were taken during quiet breathing and were effort-independent, suggested elevated respiratory resistance. These abnormalities completely disappeared after radiation therapy. The addition of impulse oscillometry to spirometry may be useful for screening CAO in routine health examinations.

The effect of anesthetic drug choice on accuracy of high-definition oscillometry in laterally recumbent horses.

PubMed

Duke-Novakovski, Tanya; Ambros, Barbara; Feng, Cindy; Carr, Anthony P

2017-05-01

To determine the accuracy of high-definition oscillometry (HDO) for arterial pressure measurement during injectable or inhalation anesthesia in horses. Prospective, clinical study. Twenty-four horses anesthetized for procedures requiring lateral recumbency. Horses were premedicated with xylazine, and anesthesia induced with diazepam-ketamine. Anesthesia was maintained with xylazine-ketamine-guaifenesin combination [TripleDrip (TD; n = 12) or isoflurane (ISO; n = 12)]. HDO was used to obtain systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressures, and heart rate (HR) using an 8-cm-wide cuff around the proximal tail. Invasive blood pressure (IBP), SAP, MAP, DAP and HR were recorded during HDO cycling. Bland-Altman analysis for repeated measures was used to compare HDO and IBP for all measurements. The generalized additive model was used to determine if means in the differences between HDO and IBP were similar between anesthetic protocols for all measurements. There were >110 paired samples for each variable. There was no effect of anesthetic choice on HDO performance, but more variability was present in TD compared with ISO. Skewed data required log-transformation for statistical comparison. Using raw data and standard Bland-Altman analysis, HDO overestimated SAP (TD, 3.8 ± 28.3 mmHg; ISO, 3.5 ± 13.6 mmHg), MAP (TD, 4.0 ± 23.3 mmHg; ISO, 6.3 ± 10.0 mmHg) and DAP (TD, 4.0 ± 21.2 mmHg; ISO, 7.8 ± 13.6 mmHg). In TD, 26-40% HDO measurements were within 10 mmHg of IBP, compared with 60-74% in ISO. Differences between HDO and IBP for all measurements were similar between anesthetic protocols. The numerical difference between IBP and HDO measurements for SAP, MAP and DAP significantly decreased as cuff width:tail girth ratio increased toward 40%. More variability in HDO occurred during TD. The cuff width:tail girth ratio is important for accuracy of HDO. Copyright © 2017 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

Validating Reference Equations for Impulse Oscillometry in Healthy Mexican Children.

PubMed

Gochicoa-Rangel, Laura; Del Río-Hidalgo, Rodrigo; Hernández-Ruiz, Juana; Rodríguez-Moreno, Luis; Martínez-Briseño, David; Mora-Romero, Uri; Cid-Juárez, Silvia; García-Sancho, Cecilia; Torre-Bouscoulet, Luis

2017-09-01

The impulse oscillometry system (IOS) measures the impedance (Z) of the respiratory system, but proper interpretation of its results requires adequate reference values. The objectives of this work were: (1) to validate the reference equations for the IOS published previously by our group and (2) to compare the adjustment of new available reference equations for the IOS from different countries in a sample of healthy children. Subjects were healthy 4-15-y-old children from the metropolitan area of Mexico City, who performed an IOS test. The functional IOS parameters obtained were compared with the predicted values from 12 reference equations determined in studies of different ethnic groups. The validation methods applied were: analysis of the differences between measured and predicted values for each reference equation; correlation and concordance coefficients; adjustment by Z-score values; percentage of predicted value; and the percentage of patients below the lower limit of normality or above the upper limit of normality. Of the 224 participants, 117 (52.3%) were girls, and the mean age was 8.6 ± 2.3 y. The equations that showed the best adjustment for the different parameters were those from the studies by Nowowiejska et al (2008) and Gochicoa et al (2015). The equations proposed by Frei et al (2005), Hellinckx et al (1998), Kalhoff et al (2011), Klug and Bisgaard (1998), de Assumpção et al (2016), and Dencker et al (2006) overestimated the airway resistance of the children in our sample, whereas the equation of Amra et al (2008) underestimated it. In the analysis of the lower and upper limits of normality, Gochicoa et al equation was the closest, since 5% of subjects were below or above percentiles 5 and 95, respectively. The study found that, in general, all of the equations showed greater error at the extremes of the age distribution. Because of the robust adjustment of the present study reference equations for the IOS, it can be recommended for both clinical and research purposes in our population. The differential adjustment of other equations underlines the need to obtain local reference values. Copyright © 2017 by Daedalus Enterprises.

Clinical application value of impulse oscillometry in geriatric patients with COPD

PubMed Central

Liu, Zhonghui; Lin, Lianjun; Liu, Xinmin

2017-01-01

Background The diagnosis and assessment of COPD rely mainly on the use of spirometry, which is an effort-dependent test and requires good patient cooperation. Impulse oscillometry (IOS) is a non-volitional method that requires less effort and cooperation and presents advantages for geriatric patients. However, the clinical application value of IOS in geriatric patients with COPD remains unclear. Aim The aim of this study was to investigate the clinical application value of IOS in geriatric patients with COPD. Subjects and methods A total of 234 subjects were retrospectively enrolled in this study, including 133 patients with COPD and 101 healthy volunteers. All the participants underwent IOS and spirometry examination. The data were collected and analyzed in the overall group, the geriatric group (aged ≥65 years), and the advanced elderly group (aged ≥80 years). Results 1) In COPD patients, a significant increase in respiratory impedance (Z5), resonant frequency (Fres), and respiratory resistance (R5, R20, R5–R20) and a decrease in respiratory reactance (X5) were observed in the overall group, the geriatric group, and the advanced elderly group compared with the healthy control subjects. 2) The IOS parameters correlated well with spirometry in COPD. In particular, R5–R20 showed the best correlation with forced expiratory volume in 1 second (FEV1) in the different age groups. 3) Fres and R5–R20 had the best diagnostic efficiency for COPD. The area under the curve (AUC) values for Fres, expressed by the receiver operating characteristic (ROC) curve, were 0.905, 0.909, and 0.914, for the different age groups, respectively. 4) The optimal cutoff values for Fres to diagnose airflow obstruction from ROC curves was 17.715 in the COPD patients. Its sensitivity and specificity were 0.789 and 0.931, respectively, and the cutoff values were similar in geriatric and advanced elderly patients. Conclusion IOS demonstrated good relevance compared with spirometry for geriatric patients with COPD. IOS may serve as an alternative method for spirometry in elderly subjects for the evaluation of the state of COPD. PMID:28352170

Relating small airways to asthma control by using impulse oscillometry in children.

PubMed

Shi, Yixin; Aledia, Anna S; Tatavoosian, Ahramahzd V; Vijayalakshmi, Shruthi; Galant, Stanley P; George, Steven C

2012-03-01

Previous reports suggest that the peripheral airways are associated with asthma control. Patient history, although subjective, is used largely to assess asthma control in children because spirometric results are many times normal values. Impulse oscillometry (IOS) is an objective and noninvasive measurement of lung function that has the potential to examine independently both small- and large-airway obstruction. We sought to determine the utility of IOS in assessing asthma control in children. Asthmatic and healthy children (6-17 years) were enrolled in the study. Spirometric and IOS (resistance of the respiratory system at 5 Hz [R5] and 20 Hz [R20], reactance of the respiratory system at 5 Hz [X5], resonant frequency of reactance [Fres], and area under the reactance curve between 5 Hz and Fres [reactance area {AX}]) values were collected in triplicate before and after a bronchodilator was administered. The physicians were blinded to the IOS measurements and assessed asthma control using American Thoracic Society guidelines. Small-airway IOS measurements, including the difference of R5 and R20 [R5-20], X5, Fres, and AX, of children with uncontrolled asthma (n = 44) were significantly different from those of children with controlled asthma (n = 57) and healthy children (n = 14), especially before the administration of a bronchodilator. However, there was no difference in large-airway IOS values (R20). No differences were found between children with controlled asthma and healthy children in any of the end points. Receiver operating characteristic analysis showed cut points for baseline R5-20 (1.5 cm H(2)O · L(-1) · s) and AX (9.5 cm H(2)O · L(-1)) that effectively discriminated controlled versus uncontrolled asthma (area under the curve, 0.86 and 0.84) and correctly classified more than 80% of the population. Uncontrolled asthma is associated with small-airways dysfunction, and IOS might be a reliable and noninvasive method to assess asthma control in children. Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Peripheral airway impairment measured by oscillometry predicts loss of asthma control in children.

PubMed

Shi, Yixin; Aledia, Anna S; Galant, Stanley P; George, Steven C

2013-03-01

We previously showed that impulse oscillometry (IOS) indices of peripheral airway function are associated with asthma control in children. However, little data exist on whether dysfunction in the peripheral airways can predict loss of asthma control. We sought to determine the utility of peripheral airway impairment, as measured by IOS, in predicting loss of asthma control in children. Fifty-four children (age, 7-17 years) with controlled asthma were enrolled in the study. Spirometric and IOS indices of airway function were obtained at baseline and at a follow-up visit 8 to 12 weeks later. Physicians who were blinded to the IOS measurements assessed asthma control (National Asthma Education and Prevention Program guidelines) on both visits and prescribed no medication change between visits. Thirty-eight (70%) patients maintained asthma control between 2 visits (group C-C), and 16 patients had asthma that became uncontrolled on the follow-up visit (group C-UC). There was no difference in baseline spirometric results between the C-C and C-UC groups, except for FEV1/forced vital capacity ratio (86% vs 82%, respectively; P < .01). Baseline IOS results, including resistance of the respiratory system at 5 Hz (R5; 6.4 vs 4.3 cm H2O · L(-1) · s), frequency dependence of resistance (difference of R5 and resistance of the respiratory system at 20 Hz [R5-20]; 2.0 vs 0.7 cm H2O · L(-1) · s), and reactance area (13.1 vs 4.1 cm H2O · L(-1)), of group C-UC were significantly higher than those of group C-C (P < .01). Receiver operating characteristic analysis showed baseline R5-20 and reactance area effectively predicted asthma control status at the follow-up visit (area under the curve, 0.91 and 0.90). Children with controlled asthma who have increased peripheral airway IOS indices are at risk of losing asthma control. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Airway reactivity in response to repeated emotional film clip presentation in asthma.

PubMed

Janssens, Thomas; Steele, Ashton M; Rosenfield, David; Ritz, Thomas

2017-02-01

Emotional stimuli elicit airway constriction in individuals with asthma and in healthy individuals, but little is known about effects of repeated stimulation. We therefore explored the effect of repeated emotion induction on respiratory resistance (R rs ) using unpleasant, high-arousal surgery films and investigated effects of respiration and emotional reactivity. Twenty-six participants (13 with asthma) watched a series of 12 short, 45-s surgery films followed by 2-min recovery periods. R rs assessed with impulse oscillometry was significantly elevated during films in both groups compared to baseline and recovered quickly after that. No habituation of airway responses occurred. R rs was higher in participants who felt more aroused and less in control when watching the films. Changes in R rs remained significant when controlling for changes in respiration or emotional experience. Thus, although unpleasant stimuli lead to elevated R rs , airway obstruction is not exacerbated with repeated stimulation due to a fast return to baseline after stimulation. Copyright © 2016 Elsevier B.V. All rights reserved.

Allergic reaction to mint leads to asthma

PubMed Central

Barnett, Tisha

2011-01-01

Respiratory and cutaneous adverse reactions to mint can result from several different mechanisms including IgE-mediated hypersensitivity, delayed-type hypersensitivity (contact dermatitis), and nonimmunologic histamine release. Reactions to cross-reacting plants of the Labiatae family, such as oregano and thyme, as well as to the chemical turpentine, may clue the clinician in on the diagnosis of mint allergy. Contact dermatitis can result from menthol in peppermint. Contact allergens have been reported in toothpastes, which often are mint-flavored. Allergic asthma from mint is less well-recognized. A case of a 54-year-old woman with dyspnea on exposure to the scent of peppermint is presented in whom mint exposure, as seemingly innocuous as the breath of others who had consumed Tic Tac candies, exacerbated her underlying asthma. This case highlights the importance of testing with multiple alternative measures of specific IgE to mint, including skin testing with mint extract, and skin testing with fresh mint leaves. Additionally, this cases suggests that asthma can result from inhaling the scent of mint and gives consideration to obtaining confirmatory pre- and postexposure pulmonary function data by both impulse oscillometry and spirometry. PMID:22852115

Genetic effects on refraction and correlation with hemodynamic variables: a twin study.

PubMed

Toth, G Zs; Tarnoki, Adam Domonkos; Tarnoki, D L; Racz, A; Szekelyhidi, Z; Littvay, L; Karlinger, K; Lannert, A; Molnar, A A; Garami, Zs; Berczi, V; Suveges, I; Nemeth, J

2014-09-01

Spherical equivalent (SE) has not been linked to increased cardiovascular morbidity. Methods: 132 Hungarian twins(age 43.3±16.9 years) underwent refraction measurements (Huvitz MRK-3100 Premium AutoRefractokeratometer)and oscillometry (TensioMed Arteriograph). Results: Heritability analysis indicated major role for genetic components in the presence of right and left SE (82.7%, 95%CI, 62.9 to 93.7%, and 89.3%, 95%CI, 72.8 to 96.6%),while unshared environmental effects accounted for 17% (95%CI, 6.3% to 37%), and 11% (95%CI, 3.4% to 26.7%)of variations adjusted for age and sex. Bilateral SE showed weak age-dependent correlations with augmentation index (AIx), aortic pulse wave velocity (r ranging between 0.218 and 0.389, all p < 0.01), aortic systolic blood pressure and pulse pressure (r between 0.188 and 0.289, p < 0.05). Conclusions: These findings support heritability of spherical equivalent, which does not coexist with altered hemodynamics (e.g. accelerated arterial aging).Accordingly, SE and the investigated hemodynamic parameters seem neither phenotypically nor genetically associated.

Exposure of healthy subjects with emissions from a gas metal arc welding process: part 3--biological effect markers and lung function.

PubMed

Brand, P; Bischof, K; Siry, L; Bertram, J; Schettgen, T; Reisgen, U; Kraus, T; Gube, M

2013-01-01

Metal active gas welding (MAG) is a widely-used welding technique resulting in high emissions of welding fume particles. This study investigated whether short-term exposure to these fume particles results in changes in lung function and early stages of inflammatory reactions. Twelve healthy, young male subjects were exposed to MAG fumes for 6 h with three different exposure concentrations in a three-fold cross-over study design. Exposure was performed in the "Aachen Workplace Simulation Laboratory" under controlled conditions with constant fume concentration. Fume concentrations were 0, 1, and 2.5 mg m(-3) in randomized order. Before and after each exposure, spirometry, and impulse oscillometry were performed and breath condensate samples were collected in order to quantify inflammatory markers like Nitrate, Nitrite, Nitrotyrosine, Hydroxyprolin and Malondialdehyde. A significant dependency on the exposure concentration could not be established for any of the endpoint parameters. In healthy, young subjects neither changes in spirometry nor changes in inflammatory markers measured in exhaled breath condensate could be detected after short-term exposure.

Clinical accuracy of inflationary oscillometry in pregnancy and pre-eclampsia: Omron-MIT Elite.

PubMed

Chung, Y; Brochut, M C; de Greeff, A; Shennan, A H

2012-10-01

To evaluate the accuracy of the Omron MIT Elite in pregnancy and pre-eclampsia according to the British Hypertension Society protocol (BHS). Prospective observational study. Antenatal clinics and wards at St. Thomas' Hospital (London, UK). Forty-five pregnant women including 15 with pre-eclampsia. Nine sequential same arm blood pressure (BP) measurements were taken from each woman by trained observers, alternating between mercury sphygmomanometry and the test device. Grading criteria of the BHS protocol (A/B grade=pass; C/D=fail). The Omron MIT Elite achieved a grade A/A in both pregnancy and pre-eclampsia. The mean difference (SD) between the mercury standard and the device in pregnancy was -1.1 (5.2)mmHg and 1.5 (4.8)mmHg for systolic and diastolic BP respectively compared to 0.2 (5.3)mmHg and 2.2 (5.5)mmHg in pre-eclampsia. The Omron MIT Elite can be recommended for use in pregnancy and pre-eclampsia according to the BHS protocol. To date, this is the most accurate automated BP device validated in pre-eclampsia. Copyright © 2012. Published by Elsevier B.V.

Comparison of Direct and Indirect Methods of Measuring Arterial Blood Pressure in Healthy Male Rhesus Macaques (Macaca mulatta).

PubMed

France, Logan K; Vermillion, Meghan S; Garrett, Caroline M

2018-01-01

Blood pressure is a critical parameter for evaluating cardiovascular health, assessing effects of drugs and procedures, monitoring physiologic status during anesthesia, and making clinical decisions. The placement of an arterial catheter is the most direct and accurate method for measuring blood pressure; however, this approach is invasive and of limited use during brief sedated examinations. The objective of this study was to determine which method of indirect blood pressure monitoring was most accurate compared with measurement by direct arterial catheterization. In addition, we sought to determine the relative accuracy of each indirect method (compared with direct arterial measurement) at a given body location and to assess whether the accuracy of each indirect method was dependent on body location. We compared direct blood pressure measurements by means of catheterization of the saphenous artery with oscillometric and ultrasonic Doppler flow detection measurements at 3 body locations (forearm, distal leg, and tail base) in 16 anesthetized, male rhesus macaques. The results indicate that oscillometry at the forearm is the best indirect method and location for accurately and consistently measuring blood pressure in healthy male rhesus macaques.

Small airway dysfunction in smokers with stable ischemic heart disease.

PubMed

Llontop, Claudia; Garcia-Quero, Cristina; Castro, Almudena; Dalmau, Regina; Casitas, Raquel; Galera, Raúl; Iglesias, Alberto; Martinez-Ceron, Elisabet; Soriano, Joan B; García-Río, Francisco

2017-01-01

A higher prevalence of airflow limitation (AL) has been described in patients with ischemic heart disease (IHD). Although small airway dysfunction (SAD) is an early feature of AL, there is little information about its occurrence in IHD patients. Our objective was to describe the prevalence of SAD in IHD patients, while comparing patient-related outcomes and future health risk among IHD patients with AL, SAD and normal lung function. In 118 consecutive smoking patients with stable IHD, comorbidities, utilization of healthcare resources, current treatment, blood biochemistry and health status were recorded. SAD was evaluated by impulse oscillometry, and pre- and post-bronchodilator spirometry was performed. The prevalence of AL and SAD were 20.3 (95% CI, 13.1-27.6%) and 26.3% (95% CI, 18.3-34.2%), respectively. Compared to the normal lung function group, patients with SAD and without AL had lower spirometric values, poorer quality of life and higher levels of C-reactive protein (CRP), as well as increased cardiovascular risk and more vascular age. In patients with normal spirometry, the presence of SAD was independently associated with pack-years, HDL-cholesterol and CRP levels. In patients with IHD, the presence of SAD is common and that it is associated with reduced health status and increased future cardiac risk.

Small airway dysfunction in smokers with stable ischemic heart disease

PubMed Central

Llontop, Claudia; Garcia-Quero, Cristina; Castro, Almudena; Dalmau, Regina; Casitas, Raquel; Galera, Raúl; Iglesias, Alberto; Martinez-Ceron, Elisabet; Soriano, Joan B.; García-Río, Francisco

2017-01-01

Background A higher prevalence of airflow limitation (AL) has been described in patients with ischemic heart disease (IHD). Although small airway dysfunction (SAD) is an early feature of AL, there is little information about its occurrence in IHD patients. Our objective was to describe the prevalence of SAD in IHD patients, while comparing patient-related outcomes and future health risk among IHD patients with AL, SAD and normal lung function. Methods In 118 consecutive smoking patients with stable IHD, comorbidities, utilization of healthcare resources, current treatment, blood biochemistry and health status were recorded. SAD was evaluated by impulse oscillometry, and pre- and post-bronchodilator spirometry was performed. Results The prevalence of AL and SAD were 20.3 (95% CI, 13.1–27.6%) and 26.3% (95% CI, 18.3–34.2%), respectively. Compared to the normal lung function group, patients with SAD and without AL had lower spirometric values, poorer quality of life and higher levels of C-reactive protein (CRP), as well as increased cardiovascular risk and more vascular age. In patients with normal spirometry, the presence of SAD was independently associated with pack-years, HDL-cholesterol and CRP levels. Conclusion In patients with IHD, the presence of SAD is common and that it is associated with reduced health status and increased future cardiac risk. PMID:28846677

Oscillating Positive Expiratory Pressure on Respiratory Resistance in Chronic Obstructive Pulmonary Disease With a Small Amount of Secretion

PubMed Central

Gastaldi, Ada Clarice; Paredi, Paolo; Talwar, Anjana; Meah, Sally; Barnes, Peter J.; Usmani, Omar S.

2015-01-01

Abstract This study aims to evaluate the acute effects of an oscillating positive expiratory pressure device (flutter) on airways resistance in patients with chronic obstructive pulmonary disease (COPD). Randomized crossover study: 15 COPD outpatients from Asthma Lab–Royal Brompton Hospital underwent spirometry, impulse oscillometry (IOS) for respiratory resistance (R) and reactance (X), and fraction exhaled nitric oxide (FeNO) measures. Thirty minutes of flutter exercises: a “flutter-sham” procedure was used as a control, and airway responses after a short-acting bronchodilator were also assessed. Respiratory system resistance (R): in COPD patients an increase in X5insp (−0.21 to −0.33 kPa/L/s) and Fres (24.95 to 26.16 Hz) occurred immediately after flutter exercises without bronchodilator. Following 20 min of rest, a decrease in the R5, ΔR5, R20, X5, and Ax was observed, with R5, R20, and X5 values lower than baseline, with a moderate effect size; there were no changes in FeNO levels or spirometry. The use of flutter can decrease the respiratory system resistance and reactance and expiratory flow limitation in stable COPD patients with small amounts of secretions. PMID:26496331

Determinants of peripheral airway function in adults with and without asthma.

PubMed

Robinson, Paul D; King, Gregory G; Sears, Malcolm R; Hong, Chuen Y; Hancox, Robert J

2017-08-01

Peripheral airway involvement in asthma remains poorly understood. We investigated impulse oscillometry (IOS) measures of peripheral airway function in a population-based birth cohort. Pre- and post-bronchodilator spirometry and IOS measures of respiratory resistance and reactance were measured in 915 participants at age 38 years. Current asthma was associated with impairments in both spirometry and IOS parameters. These impairments were greater in men and in those with childhood persistent asthma. Spirometry and IOS values for those whose asthma was in remission were not different to non-asthmatic participants. There were significant changes in IOS in both asthmatic and non-asthmatic participants after bronchodilator, but between-group differences persisted. Higher BMIs were associated with impairments in IOS but not spirometry. Cumulative tobacco use was associated with spirometric airflow obstruction in both sexes, whereas cannabis use was associated with impairments in IOS in women. Despite higher lifetime exposure, there were few associations between cannabis and IOS in men. Asthma is associated with abnormalities in IOS measures of peripheral airway dysfunction. This association is stronger in men and in those with asthma persisting since childhood. Tobacco and cannabis use are associated with different patterns of spirometry and IOS abnormalities and may affect the bronchial tree at different airway generations with differences in susceptibility between sexes. © 2017 Asian Pacific Society of Respirology.

Abnormal lung function at preschool age asthma in adolescence?

PubMed

Lajunen, Katariina; Kalliola, Satu; Kotaniemi-Syrjänen, Anne; Sarna, Seppo; Malmberg, L Pekka; Pelkonen, Anna S; Mäkelä, Mika J

2018-05-01

Asthma often begins early in childhood. However, the risk for persistence is challenging to evaluate. This longitudinal study relates lung function assessed with impulse oscillometry (IOS) in preschool children to asthma in adolescence. Lung function was measured with IOS in 255 children with asthma-like symptoms aged 4-7 years. Baseline measurements were followed by exercise challenge and bronchodilation tests. At age 12-16 years, 121 children participated in the follow-up visit, when lung function was assessed with spirometry, followed by a bronchodilation test. Asthma symptoms and medication were recorded by a questionnaire and atopy defined by skin prick tests. Abnormal baseline values in preschool IOS were significantly associated with low lung function, the need for asthma medication, and asthma symptoms in adolescence. Preschool abnormal R5 at baseline (z-score ≥1.645 SD) showed 9.2 odds ratio (95%CI 2.7;31.7) for abnormal FEV1/FVC, use of asthma medication in adolescence, and 9.9 odds ratio (95%CI 2.9;34.4) for asthma symptoms. Positive exercise challenge and modified asthma-predictive index at preschool age predicted asthma symptoms and the need for asthma medication, but not abnormal lung function at teenage. Abnormal preschool IOS is associated with asthma and poor lung function in adolescence and might be utilised for identification of asthma persistence. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Childhood Obesity Associates Haemodynamic and Vascular Changes That Result in Increased Central Aortic Pressure with Augmented Incident and Reflected Wave Components, without Changes in Peripheral Amplification

PubMed Central

Castro, Juan M.; García-Espinosa, Victoria; Curcio, Santiago; Arana, Maite; Chiesa, Pedro; Giachetto, Gustavo; Zócalo, Yanina; Bia, Daniel

2016-01-01

The aims were to determine if childhood obesity is associated with increased central aortic blood pressure (BP) and to characterize haemodynamic and vascular changes associated with BP changes in obese children and adolescents by means of analyzing changes in cardiac output (stroke volume, SV), arterial stiffness (aortic pulse wave velocity, PWV), peripheral vascular resistances (PVR), and net and relative contributions of reflected waves to the aortic pulse wave amplitude. We included 117 subjects (mean/range age: 10 (5–15) years, 49 females), who were obese (OB) or had normal weight (NW). Peripheral and central aortic BP, PWV, and pulse wave-derived parameters (augmentation index, amplitude of forward and backward components) were measured with tonometry (SphygmoCor) and oscillometry (Mobil-O-Graph). With independence of the presence of dyslipidemia, hypertension, or sedentarism, the aortic systolic and pulse BP were higher in OB than in NW subjects. The increase in central BP could not be explained by the elevation in the relative contribution of reflections to the aortic pressure wave and higher PVR or by an augmented peripheral reflection coefficient. Instead, the rise in central BP could be explained by an increase in the amplitude of both incident and reflect wave components associated to augmented SV and/or PWV. PMID:26881081

Non-invasive determination of instantaneous brachial blood flow using the oscillometric method.

PubMed

Liu, Shing-Hong; Wang, Jia-Jung; Cheng, Da-Chuan

2009-08-01

The oscillometric method has been widely used to measure arterial systolic and diastolic blood pressures, but its potential for arterial blood flow measurements still remains to be explored. The aim of this study was to non-invasively determine arterial blood flow using an oscillometric blood flow measurement system. The system consists of a pneumatic elastic cuff, an air-pumping motor, a releaser valve, a pressure transducer, and an airflow meter. To build a non-linear cuff model, we measured airflow pumped into the pneumatic cuff and cuff pressure using an airflow meter and pressure transducer during the inflation period, respectively. During the deflation period, only the pressure transducer was used to record cuff pressure. Based on the cuff model, the oscillometric blood flow waveform was obtained by integrating the oscillometric pressure waveform. We compared arterial blood flow derived from the maximum amplitude of the oscillometric blood flow waveform with Doppler-measured blood flow calculated with the diameters and blood velocities of the brachial arteries in 32 subjects who underwent diagnostic evaluations for peripheral arterial embolism. A linear correlation coefficient of r = 0.716 was found between the oscillometry- and Doppler-based blood flow measurements in the 32 subjects. These results suggest that blood flow passing through the brachial artery can be quantified non-invasively using the oscillometric approach after appropriate calibration.

Development of a tool to recognize small airways dysfunction in asthma (SADT).

PubMed

Schiphof-Godart, Lieke; van der Wiel, Erica; Ten Hacken, Nick H T; van den Berge, Maarten; Postma, Dirkje S; van der Molen, Thys

2014-11-22

Small airways dysfunction (SAD) contributes to the clinical expression of asthma. The identification of patients who suffer from SAD is important from a clinical perspective, as targeted therapy may improve patients' well-being and treatment efficacy. We aimed to realize the first step in the development of a simple small airways dysfunction tool (SADT) that may help to identify asthma patients having SAD. Asthma patients with and without SAD were interviewed. Patients were selected to participate in this study based on FEF50% and R5-R20 values from spirometry and impulse oscillometry respectively. Ten in depth interviews and two focus groups revealed that patients with and without SAD perceived differences in symptoms and signs, habits and health related issues. For example, patients with SAD reported to wheeze easily, were unable to breathe in deeply, mentioned more symptoms related to bronchial hyperresponsiveness, experienced more pronounced exercise-induced symptoms and more frequently had allergic respiratory symptoms after exposure to cats and birds. Based on these differences, 63 items were retained to be further explored for the SADT. The first step of the development of the SADT tool shows that there are relevant differences in signs and respiratory symptoms between asthma patients with and without SAD. The next step is to test and validate all items in order to retain the most relevant items to create a short and simple tool, which should be useful to identify asthma patients with SAD in clinical practice.

Effects of exercise on secretion transport, inflammation, and quality of life in patients with noncystic fibrosis bronchiectasis

PubMed Central

dos Santos, Daniele Oliveira; de Souza, Hugo Celso Dutra; Baddini-Martinez, José Antônio; Ramos, Ercy Mara Cipulo; Gastaldi, Ada Clarice

2018-01-01

Abstract Background: Bronchiectasis is characterized by pathological and irreversible bronchial dilatation caused by the inefficient mucus and microorganism clearance and progression of inflammatory processes. The most frequent characteristic is the increase in bronchial mucus production resulting in slower transport and damage to the mucociliary transport. Aims: To evaluate the effects of exercise on mucus transport, inflammation, and resistance of the respiratory and autonomic nervous systems and subsequent effects on quality of life in patients with bronchiectasis who are enrolled in a pulmonary rehabilitation program. Methods: Sixty subjects of both sexes between 18 and 60 years (30 volunteers with clinically stable bronchiectasis and 30 healthy volunteers) will be included. Participants with chronic obstructive pulmonary disease, decompensated cardiovascular or metabolic diseases, neuromuscular and musculoskeletal diseases, and active smokers will be excluded. Volunteers will be randomly allocated to the pulmonary rehabilitation or control groups. The primary outcomes will be nasal transport time as evaluated by nasal saccharin transport time, analysis of nasal lavage, enzyme immunoassay of exhaled expiration, and analysis of the mucus properties. The secondary outcomes will include pulmonary function tests, impulse oscillometry, heart rate variability analysis, and quality of life questionnaires. Discussion: In addition to the benefits for patients already described in the literature, the additional benefit of mucus removal may contribute to optimizing treatments and better control of the disease. Conclusion: This protocol could provide new information about the unclear mechanisms regarding exercise to aid in the removal of secretions. PMID:29443739

IL-10 Gene Polymorphisms Are Associated with Post-Bronchiolitis Lung Function Abnormalities at Six Years of Age

PubMed Central

Lauhkonen, Eero; Koponen, Petri; Teräsjärvi, Johanna; Gröndahl-Yli-Hannuksela, Kirsi; Vuononvirta, Juho; Nuolivirta, Kirsi; Toikka, Jyri O.; Helminen, Merja; He, Qiushui; Korppi, Matti

2015-01-01

Aim Interleukin-10 (IL-10) has been associated with wheezing and asthma in children and the genetic variation of the IL-10 cytokine production may be linked to post-bronchiolitis lung function. We used impulse oscillometry (IOS) to evaluate the associations of IL10 polymorphisms with lung function at a median age of 6.3 years in children hospitalised for bronchiolitis before six months of age. Methods We performed baseline and post-exercise IOS on 103 former bronchiolitis patients. Data on single nucleotide polymorphisms (SNP) of IL10 rs1800896 (–1082G/A), rs1800871 (–819C/T), rs1800872 (–592C/A) were available for 99 children and of IL10 rs1800890 (–3575T/A) for 98 children. Results IL10 rs1800896, rs1800871 and rs1800872 combined genotype AA+CT+CA and carriage of haplotype ATA, respectively, were associated with higher resistance and lower reactance in baseline IOS in adjusted analyses. At IL10 rs1800890, the A/A-genotype and carriers of A-allele were associated with lower reactance in baseline IOS. There were no significant associations between the studied SNPs and airway hyper-reactivity to exercise. Conclusion Low-IL-10-producing polymorphisms in the IL-10 encoding gene were associated with obstructive lung function parameters, suggesting an important role for IL-10 in development of lung function deficit in early bronchiolitis patients. PMID:26473365

Low ankle brachial index is associated with the magnitude of impaired walking endurance in patients with heart failure.

PubMed

Tanaka, Shinya; Kamiya, Kentaro; Masuda, Takashi; Hamazaki, Nobuaki; Matsuzawa, Ryota; Nozaki, Kohei; Maekawa, Emi; Noda, Chiharu; Yamaoka-Tojo, Minako; Matsunaga, Atsuhiko; Ako, Junya

2016-12-01

Measurement of the ankle brachial index (ABI) is a simple, noninvasive means of diagnosing peripheral arterial disease, and has been shown to be associated with mortality rate. Here, we examined the association between ABI and physical function in patients with heart failure (HF). The study population consisted of 524 admitted patients (67.2±13.9years, 343 males) with HF. Blood pressure and the ABI were determined by oscillometry. Prior to hospital discharge, ABI, 6-minute walking distance, walking velocity, handgrip strength, quadriceps isometric strength, and standing balance were determined. The 524 patients were divided according to ABI as follows: ABI≤0.90 (low ABI), ABI 0.91 to 0.99 (borderline ABI), and ABI 1.00 to 1.40 (normal ABI). Lower ABI values were associated with shorter 6-minute walking distance (p trend=0.001), slower walking velocity (p trend=0.023), and poorer standing balance (p trend=0.048). There were no significant associations between ABI and handgrip strength or quadriceps isometric strength. After adjusting for potential confounders, patients with ABI≤0.90 had shorter 6-minute walking distance compared to those with ABI 1.00 to 1.40 (adjusted mean value: 344m vs. 395m, respectively, p<0.001). There were no significant differences in any of the other physical function parameters examined. In patients with HF, low ABI is associated with the magnitude of impairment in walking endurance. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Oscillometric and spirometric bronchodilator response in preschool children with and without asthma

PubMed Central

Shin, Youn Ho; Jang, Sun Jung; Yoon, Jung Won; Jee, Hye Mi; Choi, Sun Hee; Yum, Hye Yung; Warburton, David; Han, Man Yong

2012-01-01

BACKGROUND: Bronchodilator responses (BDR) are routinely used in the diagnosis and management of asthma; however, their acceptability and repeatability have not been evaluated using quality control criteria for preschool children. OBJECTIVES: To compare conventional spirometry with an impulse oscillometry system (IOS) in healthy and asthmatic preschool children. METHODS: Data from 30 asthmatic children and 29 controls (two to six years of age) who underwent IOS and spirometry before and after salbutamol administration were analyzed. RESULTS: Stable asthmatic subjects significantly differed versus controls in their spirometry-assessed BDR (forced expiratory volume in 1 s [FEV1], forced vital capacity and forced expiratory flow at 25% to 75% of forced vital capacity) as well as their IOS-assessed BDR (respiratory resistance at 5 Hz [Rrs5], respiratory reactance at 5 Hz and area under the reactance curve). However, comparisons based on the area under the ROC curve for ΔFEV1 % initial versus ΔRrs5 % initial were 0.82 (95% CI 0.71 to 0.93) and 0.75 (95% CI 0.62 to 0.87), respectively. Moreover, the sensitivity and specificity for ΔFEV1 ≥9% were 0.53 and 0.93, respectively. Importantly, sensitivity increased to 0.63 when either ΔFEV1 ≥9% or ΔRrs5 ≥29% was considered as an additional criterion for the diagnosis of asthma. CONCLUSION: The accuracy of asthma diagnosis in preschool children may be increased by combining spirometry with IOS when measuring BDR. PMID:22891189

Sleep and pulmonary outcomes for clinical trials of airway plexiform neurofibromas in NF1.

PubMed

Plotkin, Scott R; Davis, Stephanie D; Robertson, Kent A; Akshintala, Srivandana; Allen, Julian; Fisher, Michael J; Blakeley, Jaishri O; Widemann, Brigitte C; Ferner, Rosalie E; Marcus, Carole L

2016-08-16

Plexiform neurofibromas (PNs) are complex, benign nerve sheath tumors that occur in approximately 25%-50% of individuals with neurofibromatosis type 1 (NF1). PNs that cause airway compromise or pulmonary dysfunction are uncommon but clinically important. Because improvement in sleep quality or airway function represents direct clinical benefit, measures of sleep and pulmonary function may be more meaningful than tumor size as endpoints in therapeutic clinical trials targeting airway PN. The Response Evaluation in Neurofibromatosis and Schwannomatosis functional outcomes group reviewed currently available endpoints for sleep and pulmonary outcomes and developed consensus recommendations for response evaluation in NF clinical trials. For patients with airway PNs, polysomnography, impulse oscillometry, and spirometry should be performed to identify abnormal function that will be targeted by the agent under clinical investigation. The functional group endorsed the use of the apnea hypopnea index (AHI) as the primary sleep endpoint, and pulmonary resistance at 10 Hz (R10) or forced expiratory volume in 1 or 0.75 seconds (FEV1 or FEV0.75) as primary pulmonary endpoints. The group defined minimum changes in AHI, R10, and FEV1 or FEV0.75 for response criteria. Secondary sleep outcomes include desaturation and hypercapnia during sleep and arousal index. Secondary pulmonary outcomes include pulmonary resistance and reactance measurements at 5, 10, and 20 Hz; forced vital capacity; peak expiratory flow; and forced expiratory flows. These recommended sleep and pulmonary evaluations are intended to provide researchers with a standardized set of clinically meaningful endpoints for response evaluation in trials of NF1-related airway PNs. © 2016 American Academy of Neurology.

Association of physical activity and physical fitness with blood pressure profile in Gujarati Indian adolescents.

PubMed

Shaikh, Wasim A; Patel, Minal C; Singh, S K

2011-01-01

The current study was conducted to determine how physical activity level and physical fitness affects the blood pressure profile of Gujarati Indian adolescents so as to help in developing preventive strategies for the local population as ethnic differences exist in the aetiopathogenesis of hypertension. A cross-sectional study was conducted on 485 Gujarati Indian adolescent boys and girls of age group 16-19 years. Physical activity level was assessed using Johnson Space Center/NASA Physical Activity Rating Scale and VO2 max was used to assess the physical fitness. Body composition was assessed in terms of Body Mass Index, Fat Mass Index and Waist Circumference. Blood Pressure was measured by oscillometry. One-way ANOVA was used to study if any significant differences (P<0.05) existed in the blood pressure profile between the high, moderate and low physical activity groups. Pearson's correlation coefficient was determined to assess the relationship between VO2 max and blood pressure profile. In girls, physical activity level was not found to have a significant effect on the blood pressure profile. In boys, systolic blood pressure and mean arterial pressure were found to be significantly higher in Moderate Physical Activity Group as compared to Low Physical Activity Group. PVO2 max was found to have a significant negative correlationship with SBP, DBP and MAP in girls and a significant negative correlationship with SBP, PP and MAP in boys. It could thus be concluded that a better physical fitness rather than a higher physical activity level could keep the blood pressure in check in the Gujarati Indian adolescents.

Evaluation of impulse oscillometry during bronchial challenge testing in children.

PubMed

Bailly, Carole; Crenesse, Dominique; Albertini, Marc

2011-12-01

The impulse oscillation system (IOS) allows easy measurement of respiratory system impedance (Zrs). The aim of this retrospective study was to evaluate the accuracy of IOS parameters obtained during methacholine challenge by comparison with "the gold standard" forced expiratory volume in the first second (FEV1). Measurements of FEV1 and resistances at 5 and 20 Hz, reactance at 5 Hz, impedance at 5 Hz and resonant frequency were performed in 227 children with suspected asthma, before and during methacholine challenge. Data were analyzed in the overall population and in three subgroups according to the final diagnosis: asthma (n = 72), chronic cough and nonspecific respiratory symptoms (n = 122), allergic rhinitis (n = 33). All IOS parameters changed significantly during the tests but only changes in X5 were significantly different between responders and nonresponders. Moreover, changes in IOS parameters were not correlated with changes in FEV1 apart from a weak correlation for X5. The receiver operating characteristic (ROC) curve for changes in X5 (to predict a 20% decrease in FEV1 showed a best decision level for a 50% decrease in X5 with a sensitivity of 36% and a specificity of 85%. Results were not different in the asthma group. The accuracy of measurements by IOS during methacholine bronchial challenge in children was not suitable when compared with FEV1 . It could be assumed that spirometry and IOS, while both providing indirect indices of airway patency, are exploring different mechanisms, each with its own methodological potentials and limitations. Copyright © 2011 Wiley Periodicals, Inc.

Arterial waveform parameters in a large, population-based sample of adults: relationships with ethnicity and lifestyle factors.

PubMed

Sluyter, J D; Hughes, A D; Thom, S A McG; Lowe, A; Camargo, C A; Hametner, B; Wassertheurer, S; Parker, K H; Scragg, R K R

2017-05-01

Little is known about how aortic waveform parameters vary with ethnicity and lifestyle factors. We investigated these issues in a large, population-based sample. We carried out a cross-sectional analysis of 4798 men and women, aged 50-84 years from Auckland, New Zealand. Participants were 3961 European, 321 Pacific, 266 Maori and 250 South Asian people. We assessed modifiable lifestyle factors via questionnaires, and measured body mass index (BMI) and brachial blood pressure (BP). Suprasystolic oscillometry was used to derive aortic pressure, from which several haemodynamic parameters were calculated. Heavy alcohol consumption and BMI were positively related to most waveform parameters. Current smokers had higher levels of aortic augmentation index than non-smokers (difference=3.7%, P<0.0001). Aortic waveform parameters, controlling for demographics, antihypertensives, diabetes and cardiovascular disease (CVD), were higher in non-Europeans than in Europeans. Further adjustment for brachial BP or lifestyle factors (particularly BMI) reduced many differences but several remained. Despite even further adjustment for mean arterial pressure, pulse rate, height and total:high-density lipoprotein cholesterol, compared with Europeans, South Asians had higher levels of all measured aortic waveform parameters (for example, for backward pressure amplitude: β=1.5 mm Hg; P<0.0001), whereas Pacific people had 9% higher log e (excess pressure integral) (P<0.0001). In conclusion, aortic waveform parameters varied with ethnicity in line with the greater prevalence of CVD among non-white populations. Generally, this was true even after accounting for brachial BP, suggesting that waveform parameters may have increased usefulness in capturing ethnic variations in cardiovascular risk. Heavy alcohol consumption, smoking and especially BMI may partially contribute to elevated levels of these parameters.

Arterial waveform parameters in a large, population-based sample of adults: relationships with ethnicity and lifestyle factors

PubMed Central

Sluyter, J D; Hughes, A D; Thom, S A McG; Lowe, A; Camargo Jr, C A; Hametner, B; Wassertheurer, S; Parker, K H; Scragg, R K R

2017-01-01

Little is known about how aortic waveform parameters vary with ethnicity and lifestyle factors. We investigated these issues in a large, population-based sample. We carried out a cross-sectional analysis of 4798 men and women, aged 50–84 years from Auckland, New Zealand. Participants were 3961 European, 321 Pacific, 266 Maori and 250 South Asian people. We assessed modifiable lifestyle factors via questionnaires, and measured body mass index (BMI) and brachial blood pressure (BP). Suprasystolic oscillometry was used to derive aortic pressure, from which several haemodynamic parameters were calculated. Heavy alcohol consumption and BMI were positively related to most waveform parameters. Current smokers had higher levels of aortic augmentation index than non-smokers (difference=3.7%, P<0.0001). Aortic waveform parameters, controlling for demographics, antihypertensives, diabetes and cardiovascular disease (CVD), were higher in non-Europeans than in Europeans. Further adjustment for brachial BP or lifestyle factors (particularly BMI) reduced many differences but several remained. Despite even further adjustment for mean arterial pressure, pulse rate, height and total:high-density lipoprotein cholesterol, compared with Europeans, South Asians had higher levels of all measured aortic waveform parameters (for example, for backward pressure amplitude: β=1.5 mm Hg; P<0.0001), whereas Pacific people had 9% higher loge (excess pressure integral) (P<0.0001). In conclusion, aortic waveform parameters varied with ethnicity in line with the greater prevalence of CVD among non-white populations. Generally, this was true even after accounting for brachial BP, suggesting that waveform parameters may have increased usefulness in capturing ethnic variations in cardiovascular risk. Heavy alcohol consumption, smoking and especially BMI may partially contribute to elevated levels of these parameters. PMID:28004730

Changes in Central Aortic Pressure Levels, Wave Components and Determinants Associated with High Peripheral Blood Pressure States in Childhood: Analysis of Hypertensive Phenotype.

PubMed

García-Espinosa, Victoria; Curcio, Santiago; Marotta, Marco; Castro, Juan M; Arana, Maite; Peluso, Gonzalo; Chiesa, Pedro; Giachetto, Gustavo; Bia, Daniel; Zócalo, Yanina

2016-10-01

The aims were to determine whether children's high peripheral blood pressure states (HBP) are associated with increased central aortic blood pressure (BP) and to characterize hemodynamic and vascular changes associated with HBP in terms of changes in cardiac output (stroke volume, SV), arterial stiffness (aortic pulse wave velocity, PWV), peripheral vascular resistances (PVR) and net and relative contributions of reflected waves to the aortic pulse amplitude. We included 154 subjects (mean age 11; range 4-16 years) assigned to one of two groups: normal peripheral BP (NBP, n = 101), defined as systolic and diastolic BP < 90th percentile, or high BP (HBP, n = 53), defined as average systolic and/or diastolic BP levels ≥90th percentile (curves for sex, age and body height). The HBP group included children with hypertensive and pre-hypertensive BP levels. After a first analysis, groups were compared excluding obese and dyslipidemic children. Peripheral and central aortic BP, PWV and pulse wave-derived parameters (augmentation index, forward and backward wave components' amplitude) were measured using gold-standard techniques, applanation tonometry (SphygmoCor) and oscillometry (Mobil-O-Graph). Independent of the presence of dyslipidemia and/or obesity, aortic systolic and pulse BP were higher in HBP than in NBP children. The increase in central BP could not be explained by an increase in the relative contribution of reflections to the aortic pressure wave, higher PVR or by an augmented peripheral reflection coefficient. Instead, the rise in central BP would be explained by an increase in the amplitude of both incident and reflected wave components.

Effects of a mixture of chloromethylisothiazolinone and methylisothiazolinone on peripheral airway dysfunction in children

PubMed Central

Cho, Hyun-Ju; Park, Dong-Uk; Yoon, Jisun; Lee, Eun; Yang, Song-I; Kim, Young-Ho; Lee, So-Yeon

2017-01-01

Background Children who were only exposed to a mixture of chloromethylisothiazolinone (CMIT) and methylisothiazolinone (MIT) as humidifier disinfectant (HD) components were evaluated for humidifier disinfectant-associated lung injury (HDLI) from 2012. This study was to evaluate the pulmonary function using, impulse oscillometry (IOS) for children exposed to a mixture of CMIT/MIT from HD. Methods Twenty-four children who were only exposed to a mixture of CMIT/MIT, with no previous underlying disease, were assessed by IOS. Diagnostic criteria for HDLI were categorized as definite, probable, possible, or unlikely. Home visits and administration of a standardized questionnaire were arranged to assess exposure characteristics. Results Definite and probable cases showed higher airborne disinfectant exposure intensity during sleep (32.4 ± 8.7 μg/m3) and younger age at initial exposure (3.5 ± 3.3 months) compared with unlikely cases (17.3 ± 11.0 μg/m3, p = 0.026; 22.5 ± 26.2 months, p = 0.039, respectively). Reactance at 5 Hz was significantly more negative in those with high-density exposure during sleep (mean, -0.463 kPa/L/s vs. low density, -0.296, p = 0.001). The reactance area was also higher with high-density exposure during sleep (mean, 3.240 kPa/L vs. low density, 1.922, p = 0.039). The mean bronchodilator response with high-density exposure was within the normal range for reactance. Conclusions Significant peripheral airway dysfunction were found in children with high levels of inhalation exposure to a mixture of CMIT/MIT during sleep. Strict regulation of a mixture of CMIT/MIT exposure were associated with positive effects on lung function of children. PMID:28453578

Sensitivity of two noninvasive blood pressure measurement techniques compared to telemetry in cynomolgus monkeys and beagle dogs.

PubMed

Mitchell, Andrea Z; McMahon, Carrie; Beck, Tom W; Sarazan, R Dustan

2010-01-01

Animals are commonly used in toxicological research for the evaluation of drug effects on the cardiovascular system. Accurate and reproducible determination of blood pressure (BP) in conscious, manually restrained monkeys and dogs is a challenge with current non-invasive cuff techniques. The High Definition Oscillometry (HDO) technique enables real time measurements with immediate visual feedback via PC screen on data validity. HDO measurements are considerably faster with a duration of approximately 8 to 15s than conventional cuff methods that can take several minutes. HDO Memo Diagnostic Model Science and Cardell BP Monitor Model 9401 measurements were compared for accuracy and reliability with simultaneously recorded direct blood pressure data captured via radiotelemetry. Six monkeys and six dogs implanted with DSI PCT telemetry transmitters were used; BP data were collected by all methods under manual constraint and compared. Measurements were performed with HDO and Cardell in the presence of a BP lowering drug (hexamethonium bromide). Systolic, diastolic, mean arterial pressure, and pulse rate were determined before, during and following up to 10mg/kg hexamethonium administration via intravenous slow bolus injection. Drug induced hemodynamic changes could be detected in monkeys and dogs with the HDO method but only in dogs with the Cardell method. Correlation coefficients were generally higher for HDO versus Telemetry than Cardell versus Telemetry comparisons, indicating that this novel, non-invasive technique produces reliable blood pressure data and is able to detect drug-induced hemodynamic changes. HDO provides an alternative approach for invasive telemetry surgeries to obtain reliable hemodynamic data in animal models for cardiovascular research when invasive techniques are not warranted. Copyright 2010 Elsevier Inc. All rights reserved.

Ankle-Brachial index by oscillometry: A very useful method to assess peripheral arterial disease in diabetes

PubMed Central

Premanath, M.; Raghunath, M.

2010-01-01

Background: Peripheral Arterial Disease (PAD) remains the least recognized form of atherosclerosis. The Ankle-Brachial Index (ABI) has emerged as one of the potent markers of diffuse atherosclerosis, cardiovascular (CV) risk, and overall survival in general public, especially in diabetics. The important reason for the lack of early diagnosis is the non-availability of a test that is easy to perform and less expensive, with no training required. Objectives: To evaluate the osillometric method of performing ABI with regard to its usefulness in detecting PAD cases and to correlate the signs and symptoms with ABI. Materials and Methods: Two hundred diabetics of varying duration attending the clinic for a period of eight months, from August 2006 to April 2007, were evaluated for signs, symptoms, and risk factors. ABI was performed using the oscillometric method. The positives were confirmed by Doppler evaluation. An equal number of age- and sex-matched controls, which were ABI negative, were also assessed by Doppler. Sensitivity and Specificity were determined. Results: There were 120 males and 80 females. Twelve males (10%) and six females (7.5%) were ABI positive. On Doppler, eleven males (91.5%) and three females (50%) were true positives. There were six false negatives from the controls (three each). The Sensitivity was 70% and Specificity was 75%. Symptoms and signs correlated well with ABI positives. Hypertension was the most important risk factor. Conclusions: In spite of the limitations, the oscillometric method of performing ABI is a simple procedure, easy to perform, does not require training and can be performed as an outpatient procedure not only by doctors, but also by the paramedical staff to detect more PAD cases. PMID:20535314

Arterial stiffness in normotensive and hypertensive subjects: Frequency in community pharmacies.

PubMed

Rodilla Sala, Enrique; Adell Alegre, Manuel; Giner Galvañ, Vicente; Perseguer Torregrosa, Zeneida; Pascual Izuel, Jose Maria; Climent Catalá, María Teresa

2017-12-07

Arterial stiffness (AS) is a well-recognized target organ lesion. This study aims to determine: 1) the frequency of AS in community pharmacies; 2) if stiffened subjects identified by brachial oscillometry have more CV risk factors than normal subjects, and 3) the dependence of stiffness on using either age-adjusted values or a fixed threshold. Observational, cross-sectional study in 32 community pharmacies of the Valencia Community, between November/2015 and April/2016. Stiffness was as pulse wave velocity (PWV) measured with a semi-automatic, validated device (Mobil-O-Graph ® , IEM), followed by a 10-item questionnaire. Mean age of the 1,427 consecutive recruited patients was 56.6 years. Overall proportion of patients with AS was 17.4% with age-adjusted PWV (9.4% in normotensives, 28.3% in hypertensives). Multivariate logistic regression showed independent association of stiffness in normotensives with male gender, obesity, higher pulse pressure and heart rate, in hypertensives, with higher pulse pressure and lower age. AS was globally found in 20.5% of subjects, defining stiffness by PWV>10m/s (6.2% in normotensives, 40.2% in hypertensives). It was associated with higher age and pulse pressure in both groups. Concordance in classifying stiffness was 74.6%. Frequency of AS varied between 17.4-20.5%. Age-adjusted stiffness is associated in normotensives with male gender, pulse pressure, obesity and heart rate, in hypertensives with pulse pressure and inversely to age. Stiffness by 10m/s is determined by higher pulse pressure and higher age. Both definitions of PWV are not interchangeable. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Diagnostic value of a pattern of exhaled breath condensate biomarkers in asthmatic children.

PubMed

Maloča Vuljanko, I; Turkalj, M; Nogalo, B; Bulat Lokas, S; Plavec, D

Diagnosing asthma in children is a challenge and using a single biomarker from exhaled breath condensate (EBC) showed the lack of improvement in it. The aim of this study was to assess the diagnostic potential of a pattern of simple chemical biomarkers from EBC in diagnosing asthma in children in a real-life setting, its association with lung function and gastroesophageal reflux disease (GERD). In 75 consecutive children aged 5-7 years with asthma-like symptoms the following tests were performed: skin prick tests, spirometry, impulse oscillometry (IOS), exhaled NO (F E NO), 24-hour oesophageal pH monitoring and EBC collection with subsequent analysis of pH, carbon dioxide tension, oxygen tension, and concentrations of magnesium, calcium, iron and urates. No significant differences were found for individual EBC biomarkers between asthmatics and non-asthmatics (p>0.05 for all). A pattern of six EBC biomarkers showed a statistically significant (p=0.046) predictive model for asthma (AUC=0.698, PPV=84.2%, NPV=38.9%). None to moderate association (R 2 up to 0.43) between EBC biomarkers and lung function measures and F E NO was found, with IOS parameters showing the best association with EBC biomarkers. A significantly higher EBC Fe was found in children with asthma and GERD compared to asthmatics without GERD (p=0.049). An approach that involves a pattern of EBC biomarkers had a better diagnostic accuracy for asthma in children in real-life settings compared to a single one. Poor to moderate association of EBC biomarkers with lung function suggests a complementary value of EBC analysis for asthma diagnosis in children. Copyright © 2016 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

Effects of granulocyte colony stimulating factor on retinal leukocyte and erythrocyte flux in the human retina.

PubMed

Fuchsjäger-Mayrl, Gabriele; Malec, Magdalena; Polska, Elzbieta; Jilma, Bernd; Wolzt, Michael; Schmetterer, Leopold

2002-05-01

The blue-field entoptic technique was introduced more than 20 years ago to quantify perimacular white blood cell flux. However, a final confirmation that the perceived corpuscles represent leukocytes is still unavailable. The study design was randomized, placebo-controlled, and double masked with two parallel groups. Fifteen healthy male subjects received a single dose of granulocyte colony stimulating factor (G-CSF, 300 microg) and 15 other subjects received placebo. The following parameters were assessed at baseline and at 12 minutes and 8 hours after administration: retinal white blood cell flux, with the blue-field entoptic technique; retinal blood velocities, with bidirectional laser Doppler velocimetry; retinal venous diameter determined with a retinal vessel analyzer; and blood pressure and pulse rate determined by automated oscillometry and pulse oxymetry, respectively. After 12 minutes, G-CSF reduced total leukocyte count from 5.5 +/- 1.4 10(9)/L at baseline to 1.9 +/- 0.4 10(9)/L. This was paralleled by a 35% +/- 11% decrease in retinal white blood cell density. After 8 hours G-CSF increased total leukocyte counts to 20.0 +/- 4.4 10(9)/L. Again, this increase in circulating leukocytes was reflected by an increase in retinal white blood cell density (110% +/- 48%). All effects were significant at P < 0.001. By contrast, none of the other hemodynamic parameters was changed by administration of G-CSF. The results clearly indicate that the blue-field entoptic technique assesses leukocyte movement in the perimacular capillaries of the retina. Moreover, white blood cell density appears to adequately reflect the number of circulating leukocytes within the retinal microvasculature. Hence, an increase in retinal white blood cell density does not necessarily reflect retinal vasodilatation.

Deposition efficiency of inhaled particles (15-5000 nm) related to breathing pattern and lung function: an experimental study in healthy children and adults.

PubMed

Rissler, Jenny; Gudmundsson, Anders; Nicklasson, Hanna; Swietlicki, Erik; Wollmer, Per; Löndahl, Jakob

2017-04-08

Exposure to airborne particles has a major impact on global health. The probability of these particles to deposit in the respiratory tract during breathing is essential for their toxic effects. Observations have shown that there is a substantial variability in deposition between subjects, not only due to respiratory diseases, but also among individuals with healthy lungs. The factors determining this variability are, however, not fully understood. In this study we experimentally investigate factors that determine individual differences in the respiratory tract depositions of inhaled particles for healthy subjects at relaxed breathing. The study covers particles of diameters 15-5000 nm and includes 67 subjects aged 7-70 years. A comprehensive examination of lung function was performed for all subjects. Principal component analyses and multiple regression analyses were used to explore the relationships between subject characteristics and particle deposition. A large individual variability in respiratory tract deposition efficiency was found. Individuals with high deposition of a certain particle size generally had high deposition for all particles <3500 nm. The individual variability was explained by two factors: breathing pattern, and lung structural and functional properties. The most important predictors were found to be breathing frequency and anatomical airway dead space. We also present a linear regression model describing the deposition based on four variables: tidal volume, breathing frequency, anatomical dead space and resistance of the respiratory system (the latter measured with impulse oscillometry). To understand why some individuals are more susceptible to airborne particles we must understand, and take into account, the individual variability in the probability of particles to deposit in the respiratory tract by considering not only breathing patterns but also adequate measures of relevant structural and functional properties.

Heart Rate Variability Biofeedback Does Not Substitute for Asthma Steroid Controller Medication.

PubMed

Lehrer, Paul M; Irvin, Charles G; Lu, Shou-En; Scardella, Anthony; Roehmheld-Hamm, Beatrix; Aviles-Velez, Milisyaris; Graves, Jessica; Vaschillo, Evgeny G; Vaschillo, Bronya; Hoyte, Flavia; Nelson, Harold; Wamboldt, Frederick S

2018-03-01

Despite previous findings of therapeutic effects for heart rate variability biofeedback (HRVB) on asthma, it is not known whether HRVB can substitute either for controller or rescue medication, or whether it affects airway inflammation. Sixty-eight paid volunteer steroid naïve study participants with mild or moderate asthma were given 3 months of HRVB or a comparison condition consisting of EEG alpha biofeedback with relaxing music and relaxed paced breathing (EEG+), in a two-center trial. All participants received a month of intensive asthma education prior to randomization. Both treatment conditions produced similar significant improvements on the methacholine challenge test (MCT), asthma symptoms, and asthma quality of life (AQOL). MCT effects were of similar size to those of enhanced placebo procedures reported elsewhere, and were 65% of those of a course of a high-potency inhaled steroid budesonide given to a sub-group of participants following biofeedback training. Exhaled nitric oxide decreased significantly only in the HRVB group, 81% of the budesonide effect, but with no significant differences between groups. Participants reported becoming more relaxed during practice of both techniques. Administration of albuterol after biofeedback sessions produced a large improvement in pulmonary function test results, indicating that neither treatment normalized pulmonary function as a potent controller medication would have done. Impulse oscillometry showed increased upper airway (vocal cord) resistance during biofeedback periods in both groups. These data suggest that HRVB should not be considered an alternative to asthma controller medications (e.g., inhaled steroids), although both biofeedback conditions produced some beneficial effects, warranting further research, and suggesting potential complementary effects. Various hypotheses are presented to explain why HRVB effects on asthma appeared smaller in this study than in earlier studies. Clinical Trial Registration NCT02766374.

Exercise-associated Excessive Dynamic Airway Collapse in Military Personnel.

PubMed

Weinstein, Daniel J; Hull, James E; Ritchie, Brittany L; Hayes, Jackie A; Morris, Michael J

2016-09-01

Evaluation of military personnel for exertional dyspnea can present a diagnostic challenge, given multiple unique factors that include wide variation in military deployment. Initial consideration is given to common disorders such as asthma, exercise-induced bronchospasm, and inducible laryngeal obstruction. Excessive dynamic airway collapse has not been reported previously as a cause of dyspnea in these individuals. To describe the clinical and imaging characteristics of military personnel with exertional dyspnea who were found to have excessive dynamic collapse of large airways during exercise. After deployment to Afghanistan or Iraq, 240 active U.S. military personnel underwent a standardized evaluation to determine the etiology of persistent dyspnea on exertion. Study procedures included full pulmonary function testing, impulse oscillometry, exhaled nitric oxide measurement, methacholine challenge testing, exercise laryngoscopy, cardiopulmonary exercise testing, and fiberoptic bronchoscopy. Imaging included high-resolution computed tomography with inspiratory and expiratory views. Selected individuals underwent further imaging with dynamic computed tomography. A total of five men and one woman were identified as having exercise-associated excessive dynamic airway collapse on the basis of the following criteria: (1) exertional dyspnea without resting symptoms, (2) focal expiratory wheezing during exercise, (3) functional collapse of the large airways during bronchoscopy, (4) expiratory computed tomographic imaging showing narrowing of a large airway, and (5) absence of underlying apparent pathology in small airways or pulmonary parenchyma. Identification of focal expiratory wheezing correlated with bronchoscopic and imaging findings. Among 240 military personnel evaluated after presenting with postdeployment exertional dyspnea, a combination of symptoms, auscultatory findings, imaging, and visualization of the airways by bronchoscopy identified six individuals with excessive dynamic central airway collapse as the sole apparent cause of dyspnea. Exercise-associated excessive dynamic airway collapse should be considered in the differential diagnosis of exertional dyspnea.

Comparison of noninvasive blood pressure measurement techniques via the coccygeal artery in anesthetized cheetahs (Acinonyx jubatus).

PubMed

Sadler, Ryan A; Hall, Natalie H; Kass, Philip H; Citino, Scott B

2013-12-01

Two indirect blood pressure measurement techniques, Doppler (DOP) sphygmomanometry and oscillometry, applied at the ventral coccygeal artery were compared with simultaneous direct blood pressure measurements at the dorsal pedal artery in 10 anesthetized, captive cheetahs (Acinonyx jubatus). The DOP method was moderately accurate, with relatively little bias (mean difference 3.8 mmHg) and 88.6% of the DOP systolic arterial pressure measurements being within 10 mmHg of the direct systolic arterial measurement. With the oscillometric (OM) method, 89.2% of the mean arterial pressure measurements were within 10 mmHg of the direct measurement and had the least bias (mean difference 2.3 mmHg), 80.7% of the systolic measurements were within 10 mmHg of the direct measurement and had the second least bias (mean difference 2.3 mmHg), and 59% of the diastolic measurements were within 10 mmHg of the direct measurement and had significant bias (mean difference 7.3 mmHg). However, DOP showed relatively poor precision (SD 11.2 mmHg) compared with OM systolic (SD 8.0 mmHg), diastolic (SD 8.6 mmHg), and mean (SD 5.7 mmHg). Both techniques showed a linear relationship with the direct technique measurements over a wide range of blood pressures. The DOP method tended to underestimate systolic measurements below 160 mmHg and overestimate systolic measurements above 160 mmHg. The OM method tended to underestimate mean pressures below 160 mm Hg, overestimate mean pressures above 160 mmHg, underestimate systolic pressures below 170 mmHg, overestimate systolic pressures above 170 mmHg, and underestimate diastolic pressures throughout the measured blood pressure range. Indirect blood pressure measurement using the ventral coccygeal artery, particularly when using an OM device for mean and systolic arterial pressure, may be useful in the clinical assessment of cheetahs when monitoring trends over time, but caution should be taken when interpreting individual values.

COMPARISON OF HIGH-DEFINITION OSCILLOMETRIC AND DIRECT ARTERIAL BLOOD PRESSURE MEASUREMENT IN ANESTHETIZED CHEETAHS (ACINONYX JUBATUS).

PubMed

Sant Cassia, Emma V; Boswood, Adrian; Tordiffe, Adrian S W

2015-09-01

Blood pressure measurement reveals important insights into the health of conscious and anesthetized individuals. This is of particular interest in cheetahs (Acinonyx jubatus), which in captivity are known to suffer from chronic diseases that may be associated with hypertension and which often require immobilization for transport or veterinary treatment. Invasive testing methods are considered the gold standard but are not practical in many settings. Consequently, it is important to evaluate the use of noninvasive methods in this species. Measurements for systolic, diastolic, and mean arterial pressure obtained using high-definition oscillometry (HDO) at the coccygeal artery were compared to simultaneous direct measurements obtained via catheterization of the femoral or dorsal pedal artery in eight anesthetized captive cheetahs during nine anesthetic events. Overall, HDO and direct measurements agreed most closely for mean arterial pressure, and the poorest agreement was observed for systolic pressure. There was a tendency for low diastolic pressures to be underestimated and for high diastolic pressures to be overestimated. Across all three parameters, HDO measurements from the tail overestimated directly measured pressures in the femoral artery and underestimated those in the dorsal pedal artery. HDO agreed most closely with directly measured dorsal pedal pressures. Mean arterial pressure showed the greatest precision (standard deviation of 10.2 mm Hg) and lowest bias (-1.2 mm Hg), with 75.9% of readings within 10 mm Hg of the direct dorsal pedal pressure. Agreement with systolic pressure was hindered by a high bias (-10.4 mm Hg), but if a correction factor of +10 mm Hg was applied to all systolic measurements, agreement was improved and 65.7% of readings were within 10 mm Hg of the direct pressure. When compared to criteria defined by the American College of Veterinary Internal Medicine for validation of blood pressure devices, results were favorable, but a limited sample size prevented formal validation.

Pulse wave velocity and augmentation index are not independently associated with carotid atherosclerosis in patients with rheumatoid arthritis.

PubMed

Robustillo-Villarino, M; Alegre-Sancho, J J; Rodilla-Sala, E; Corrales, A; Llorca, J; Gonzalez-Gay, M A; Dessein, P H

2017-11-01

Arterial stiffness can enhance cardiovascular risk by increasing atherogenesis or adverse hemodynamic effects. We examined whether the arterial stiffness markers of aortic pulse wave velocity (PWV) and the augmentation index (AIx) are independently associated with carotid artery intima-media thickness (IMT) and plaque in patients with rheumatoid arthritis (RA). PWV and AIx were determined by brachial oscillometry using the Mobil-O-Graph® system and carotid IMT and plaque by ultrasound in 194 consecutive RA patients without established cardiovascular disease, chronic kidney disease, and diabetes at disease onset. In crude analysis, PWV was associated with IMT (β (95% CI) = 0.04 (0.03 to 0.05), p value < 0.0001) and plaque (OR (95% CI) = 1.69 (1.40 to 2.04), p value < 0.0001). Upon adjustment for the confounders of age, sex, mean blood pressure, body height, and cardiovascular risk factors comprising smoking, the atherogenic index, and diabetes, PWV was not related to IMT (β (95% CI) = 0.01 (-0.02 to 0.04), p value = 0.5) or plaque (OR (95% CI) = 0.99 (0.96 to 1.01), p value = 0.3). AIx was not associated with IMT in crude (β (95% CI) = -0.002 (-0.004 to 0.007), p value = 0.2) and adjusted analyses (β (95% CI) = -0.002 (-0.004 to 0.000), p value = 0.06). AIx was also unrelated to carotid plaque in crude (OR (95% CI) = 1.04 (0.60 to 1.82), p value = 0.9) and adjusted analyses (OR (95% CI) = 0.97 (0.94 to 1.01), p value = 0.1). PWV and AIx are not independently associated with subclinical carotid atherosclerosis in RA.

Recanalization of Acute and Subacute Femoropopliteal Artery Occlusions with the Rotarex Catheter: One Year Follow-up, Single Center Experience

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

Duc, Sylvain R., E-mail: Sylvain.duc@balgrist.ch; Schoch, Eric; Pfyffer, Markus

2005-06-15

Purpose:To assess the efficacy and safety of a new rotational catheter for percutaneous removal of fresh and organized thrombi in the femoropopliteal artery.Methods:Forty-one limbs in 38 patients (age 56-90 years, mean 75.6 years) with acute, subacute or chronic femoropopliteal occlusions of 1-180 days' duration (mean 31.6 days) were treated with the Rotarex device. The Fontaine stage was mainly IIB (Rutherford 2-3, 22 patients) or III (Rutherford 4, 14 patients). The length of occlusion varied from 2 to 35 cm (mean 13.1 cm). After recanalization percutaneous transluminal angioplasty (PTA) was performed if there was a residual stenosis of >25%. Patients weremore » followed up with color Doppler ultrasound at 48 hr and clinically with Doppler pressures and oscillometry at 3, 6, and 12 months.Results:After an average of two passages with the Rotarex catheter all but two limbs required PTA for residual stenosis >25%. Five patients needed additional stenting. Major complications were one groin hematoma requiring blood transfusion and one arteriovenous fistula spontaneously thrombosing after unsuccessful primary prolonged balloon dilation. Distal embolizations occurred in 10 patients; 6 clinically relevant emboli were aspirated. All occlusions were technically successfully recanalised there were 2 early reocclusions after 1 day and two at 2 weeks. Brachial-ankle indices improved from an average of 0.41 before to 0.93 after recanalization. Primary and secondary patency rates were 62% / 84% after 6 months and 39% / 68% after 1 year. The amputation-free survival at 12 months was 100%.Conclusion:The Rotarex mechanical thrombectomy device is an efficient, quick, easy to handle, and safe tool for the treatment of acute, subacute or even chronic peripheral arterial thromboembolic occlusions. It can be used for short or long occlusions with equal success, provided the obstruction is not heavily calcified and has been safely passed with a guidewire first.« less

Importance of Calibration Method in Central Blood Pressure for Cardiac Structural Abnormalities.

PubMed

Negishi, Kazuaki; Yang, Hong; Wang, Ying; Nolan, Mark T; Negishi, Tomoko; Pathan, Faraz; Marwick, Thomas H; Sharman, James E

2016-09-01

Central blood pressure (CBP) independently predicts cardiovascular risk, but calibration methods may affect accuracy of central systolic blood pressure (CSBP). Standard central systolic blood pressure (Stan-CSBP) from peripheral waveforms is usually derived with calibration using brachial SBP and diastolic BP (DBP). However, calibration using oscillometric mean arterial pressure (MAP) and DBP (MAP-CSBP) is purported to provide more accurate representation of true invasive CSBP. This study sought to determine which derived CSBP could more accurately discriminate cardiac structural abnormalities. A total of 349 community-based patients with risk factors (71±5years, 161 males) had CSBP measured by brachial oscillometry (Mobil-O-Graph, IEM GmbH, Stolberg, Germany) using 2 calibration methods: MAP-CSBP and Stan-CSBP. Left ventricular hypertrophy (LVH) and left atrial dilatation (LAD) were measured based on standard guidelines. MAP-CSBP was higher than Stan-CSBP (149±20 vs. 128±15mm Hg, P < 0.0001). Although they were modestly correlated (rho = 0.74, P < 0.001), the Bland-Altman plot demonstrated a large bias (21mm Hg) and limits of agreement (24mm Hg). In receiver operating characteristic (ROC) curve analyses, MAP-CSBP significantly better discriminated LVH compared with Stan-CSBP (area under the curve (AUC) 0.66 vs. 0.59, P = 0.0063) and brachial SBP (0.62, P = 0.027). Continuous net reclassification improvement (NRI) (P < 0.001) and integrated discrimination improvement (IDI) (P < 0.001) corroborated superior discrimination of LVH by MAP-CSBP. Similarly, MAP-CSBP better distinguished LAD than Stan-CSBP (AUC 0.63 vs. 0.56, P = 0.005) and conventional brachial SBP (0.58, P = 0.006), whereas Stan-CSBP provided no better discrimination than conventional brachial BP (P = 0.09). CSBP is calibration dependent and when oscillometric MAP and DBP are used, the derived CSBP is a better discriminator for cardiac structural abnormalities. © American Journal of Hypertension, Ltd 2016. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Validity and reliability of central blood pressure estimated by upper arm oscillometric cuff pressure.

PubMed

Climie, Rachel E D; Schultz, Martin G; Nikolic, Sonja B; Ahuja, Kiran D K; Fell, James W; Sharman, James E

2012-04-01

Noninvasive central blood pressure (BP) independently predicts mortality, but current methods are operator-dependent, requiring skill to obtain quality recordings. The aims of this study were first, to determine the validity of an automatic, upper arm oscillometric cuff method for estimating central BP (O(CBP)) by comparison with the noninvasive reference standard of radial tonometry (T(CBP)). Second, we determined the intratest and intertest reliability of O(CBP). To assess validity, central BP was estimated by O(CBP) (Pulsecor R6.5B monitor) and compared with T(CBP) (SphygmoCor) in 47 participants free from cardiovascular disease (aged 57 ± 9 years) in supine, seated, and standing positions. Brachial mean arterial pressure (MAP) and diastolic BP (DBP) from the O(CBP) device were used to calibrate in both devices. Duplicate measures were recorded in each position on the same day to assess intratest reliability, and participants returned within 10 ± 7 days for repeat measurements to assess intertest reliability. There was a strong intraclass correlation (ICC = 0.987, P < 0.001) and small mean difference (1.2 ± 2.2 mm Hg) for central systolic BP (SBP) determined by O(CBP) compared with T(CBP). Ninety-six percent of all comparisons (n = 495 acceptable recordings) were within 5 mm Hg. With respect to reliability, there were strong correlations but higher limits of agreement for the intratest (ICC = 0.975, P < 0.001, mean difference 0.6 ± 4.5 mm Hg) and intertest (ICC = 0.895, P < 0.001, mean difference 4.3 ± 8.0 mm Hg) comparisons. Estimation of central SBP using cuff oscillometry is comparable to radial tonometry and has good reproducibility. As a noninvasive, relatively operator-independent method, O(CBP) may be as useful as T(CBP) for estimating central BP in clinical practice.

Pulmonary Vascular Congestion: A Mechanism for Distal Lung Unit Dysfunction in Obesity.

PubMed

Oppenheimer, Beno W; Berger, Kenneth I; Ali, Saleem; Segal, Leopoldo N; Donnino, Robert; Katz, Stuart; Parikh, Manish; Goldring, Roberta M

2016-01-01

Obesity is characterized by increased systemic and pulmonary blood volumes (pulmonary vascular congestion). Concomitant abnormal alveolar membrane diffusion suggests subclinical interstitial edema. In this setting, functional abnormalities should encompass the entire distal lung including the airways. We hypothesize that in obesity: 1) pulmonary vascular congestion will affect the distal lung unit with concordant alveolar membrane and distal airway abnormalities; and 2) the degree of pulmonary congestion and membrane dysfunction will relate to the cardiac response. 54 non-smoking obese subjects underwent spirometry, impulse oscillometry (IOS), diffusion capacity (DLCO) with partition into membrane diffusion (DM) and capillary blood volume (VC), and cardiac MRI (n = 24). Alveolar-capillary membrane efficiency was assessed by calculation of DM/VC. Mean age was 45±12 years; mean BMI was 44.8±7 kg/m2. Vital capacity was 88±13% predicted with reduction in functional residual capacity (58±12% predicted). Despite normal DLCO (98±18% predicted), VC was elevated (135±31% predicted) while DM averaged 94±22% predicted. DM/VC varied from 0.4 to 1.4 with high values reflecting recruitment of alveolar membrane and low values indicating alveolar membrane dysfunction. The most abnormal IOS (R5 and X5) occurred in subjects with lowest DM/VC (r2 = 0.31, p<0.001; r2 = 0.34, p<0.001). Cardiac output and index (cardiac output / body surface area) were directly related to DM/VC (r2 = 0.41, p<0.001; r2 = 0.19, p = 0.03). Subjects with lower DM/VC demonstrated a cardiac output that remained in the normal range despite presence of obesity. Global dysfunction of the distal lung (alveolar membrane and distal airway) is associated with pulmonary vascular congestion and failure to achieve the high output state of obesity. Pulmonary vascular congestion and consequent fluid transudation and/or alterations in the structure of the alveolar capillary membrane may be considered often unrecognized causes of airway dysfunction in obesity.

Evaluation of indirect blood pressure monitoring in awake and anesthetized red-tailed hawks (Buteo jamaicensis): effects of cuff size, cuff placement, and monitoring equipment.

PubMed

Zehnder, Ashley M; Hawkins, Michelle G; Pascoe, Peter J; Kass, Philip H

2009-09-01

To compare Doppler and oscillometric methods of indirect arterial blood pressure (IBP) with direct arterial measurements in anesthetized and awake red-tailed hawks. Prospective, randomized, blinded study. Six, sex unknown, adult red-tailed hawks. Birds were anesthetized and IBP measurements were obtained by oscillometry (IBP-O) and Doppler (IBP-D) on the pectoral and pelvic limbs using three cuffs of different width based on limb circumference: cuff 1 (20-30% of circumference), cuff 2 (30-40%), and cuff 3 (40-50%). Direct arterial pressure measurements were obtained from the contralateral superficial ulnar artery. Indirect blood pressure measurements were compared to direct systolic arterial pressure (SAP) and mean arterial pressure (MAP) during normotension and induced states of hypotension and hypertension. Measurements were also obtained in awake, restrained birds. Three-way anova, linear regression and Bland-Altman analyses were used to evaluate the IBP-D data. Results are reported as mean bias (95% confidence intervals). The IBP-O monitor reported errors during 54% of the measurements. Indirect blood pressure Doppler measurements were most accurate with cuff 3 and were comparable to MAP with a bias of 2 (-9, 13 mmHg). However, this cuff consistently underestimated SAP with a bias of 33 (19, 48 mmHg). Variability in the readings within and among birds was high. There was no significant difference between sites of cuff placement. Awake birds had SAP, MAP and diastolic arterial pressure that were 56, 43, and 38 mmHg higher than anesthetized birds. Indirect blood pressure (oscillometric) measurements were unreliable in red-tailed hawks. Indirect blood pressure (Doppler) measurements were closer to MAP measurements than SAP measurements. There was slightly better agreement with the use of cuff 3 on either the pectoral or pelvic limbs. Awake, restrained birds have significantly higher arterial pressures than those under sevoflurane anesthesia.

The Prevention of Early Asthma in Kids study: design, rationale and methods for the Childhood Asthma Research and Education network.

PubMed

Guilbert, Theresa W; Morgan, Wayne J; Krawiec, Marzena; Lemanske, Robert F; Sorkness, Chris; Szefler, Stanley J; Larsen, Gary; Spahn, Joseph D; Zeiger, Robert S; Heldt, Gregory; Strunk, Robert C; Bacharier, Leonard B; Bloomberg, Gordon R; Chinchilli, Vernon M; Boehmer, Susan J; Mauger, Elizabeth A; Mauger, David T; Taussig, Lynn M; Martinez, Fernando D

2004-06-01

Pediatric asthma remains an important public health concern as its prevalence and cost to the health care system is rising. In order to promote innovative research in asthma therapies, the National Heart, Lung and Blood Institute created the Childhood Asthma Research and Education Network in 1999. As its first study, the steering committee of the Childhood Asthma Research and Education Network designed a randomized clinical trial to determine if persistent asthma could be prevented in children at a high risk to develop the disease. This communication presents the design of its first clinical trial, the Prevention of Asthma in Kids (PEAK) trial and the organization of the Childhood Asthma Research and Education Network that developed and implemented this trial. Studies of the natural history of asthma have shown that, in persistent asthma, the initial asthma-like symptoms and loss of lung function occur predominately during the first years of life. Therefore, in the Prevention of Asthma in Kids study, children 2 and 3 years old with a positive asthma predictive index were randomized to twice daily treatment with fluticasone 88 microg or placebo via metered-dose inhaler and Aerochamber for 2 years. The double blind treatment period was followed by a 1-year observational period. Lung function was measured by spirometry and oscillometry technique at 4-month intervals throughout the study. Bronchodilator reversibility and exhaled nitric oxide (ENO) studies were performed at the end of the treatment and observation periods. The primary outcome measure was the number of asthma-free days. Other secondary outcomes included number of exacerbations, use of asthma medications and lung function. These measures were chosen to reflect the progression of the disease from intermittent wheezing to persistent asthma and measurement of the extent of airflow limitation and airway reactivity.

Gene Polymorphism of Toll-Like Receptors and Lung Function at Five to Seven Years of Age after Infant Bronchiolitis

PubMed Central

Lauhkonen, Eero; Koponen, Petri; Vuononvirta, Juho; Teräsjärvi, Johanna; Nuolivirta, Kirsi; Toikka, Jyri O.; Helminen, Merja; He, Qiushui; Korppi, Matti

2016-01-01

Aim Toll-like receptors (TLR) play a crucial role in innate immunity, protecting the host from pathogens such as viruses. Genetic variations in TLRs have been associated with the severity of viral bronchiolitis in infancy and with the later occurrence of post-bronchiolitis asthma. The aim of the present study was to evaluate if there are any exploratory associations between TLR gene polymorphisms and lung function at 5 to 7 years of age in former bronchiolitis patients. Methods We performed impulse oscillometry (IOS) at the median age of 6.3 years for 103 children who had been hospitalized for bronchiolitis at less than six months of age. The main parameters evaluated were airway resistance and reactance at 5Hz in baseline and post-exercise measurements. Data on single nucleotide polymorphisms (SNP) of TLR1 rs5743618, TLR2 rs5743708, TLR6 rs5743810 and TLR10 rs4129009 (TLR2 subfamily) and TLR3 rs3775291, TLR4 rs4986790, TLR7 rs179008, TLR8 rs2407992 and TLR 9 rs187084 were available for analyses. Results The TLR4 rs4986790 wild genotype A/A was associated with a greater Rrs5 response (0.72 vs. -0.42, p = 0.03) to exercise. In TLR6 rs5743810, the minor allele T was associated with greater Rrs5 response (0.80 vs. -0.03, p = 0.04) to exercise. In TLR7 rs179008, the major allele A was associated with baseline decline in dRrs/df (-1.03 vs 0.61, p = 0.01) and increased Fres (2.28 vs. 0.89, p = 0.01) in girls. Conclusion Among the nine studied TLRs, only TLR7 rs179008 showed some exploratory associations with post-bronchiolitis lung function deficiency, and polymorphisms of TLR4 rs4986790, and TLR6 rs5743810 in particular, with airway reactivity. These findings call for further confirmatory studies. PMID:26741133

Impulse oscillometry system as an alternative diagnostic method for chronic obstructive pulmonary disease.

PubMed

Wei, Xia; Shi, Zhihong; Cui, Yajuan; Mi, Jiuyun; Ma, Zhengquan; Ren, Jingting; Li, Jie; Xu, Shudi; Guo, Youmin

2017-11-01

We aimed to compare impulse oscillation system (IOS) and traditional pulmonary function tests (PFTs) for the assessment of the severity of chronic obstructive pulmonary disease (COPD), and to assess the use of IOS parameters to identify patients who were forced expiratory volume in 1 second (FEV1)%pred < 50%.Patients with COPD (n = 215) were enrolled at the Ninth Hospital of Xi'an Affiliated Hospital of Xi'an Jiaotong University between October 2014 and September 2016. All patients were assessed by traditional PFT and IOS. Diagnostic performance of IOS parameters to determine indication for patients of FEV1%pred < 50% was assessed on receiver-operating characteristics (ROC) curve analysis.Out of 215 patients, 18, 83, 78, and 36 patients were classified as grade 1, 2, 3, and 4, respectively, according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) severity grading. On Spearman correlation analysis, FEV1%pred, MMEF 75%-25%, and residual volume/total lung capacity (RV/TLC) correlated with total respiratory impedance (Z5)%pred, resistance at 5 Hz (R5)-resistance at 20 Hz (R20), R5-R20% R5, R5, R5%pred, frequency response (Fres), reactance area (Ax), and reactance at 5 Hz (X5). On ROC curve analysis, the area under the curve (AUC) of X5 absolute value, Fres, Ax, Z5%pred, R5-R20, and R5-R20% R5 were 0.748, 0.755, 0.760, 0.705, 0.715, and 0.735, respectively, for COPD patients who required inhalational glucocorticoid therapy.IOS parameters showed a good correlation with traditional pulmonary function parameters; reactance parameters showed a stronger correlation than that of the resistance parameters. IOS can be used as an alternative method for pulmonary function assessment in patients with COPD with FEV1%pred < 50% who need inhalational glucocorticoid therapy. ChiCTR-OCH-14004904.

Impulse oscillometry system as an alternative diagnostic method for chronic obstructive pulmonary disease

PubMed Central

Wei, Xia; Shi, Zhihong; Cui, Yajuan; Mi, Jiuyun; Ma, Zhengquan; Ren, Jingting; Li, Jie; Xu, Shudi; Guo, Youmin

2017-01-01

Abstract We aimed to compare impulse oscillation system (IOS) and traditional pulmonary function tests (PFTs) for the assessment of the severity of chronic obstructive pulmonary disease (COPD), and to assess the use of IOS parameters to identify patients who were forced expiratory volume in 1 second (FEV1)%pred < 50%. Patients with COPD (n = 215) were enrolled at the Ninth Hospital of Xi’an Affiliated Hospital of Xi’an Jiaotong University between October 2014 and September 2016. All patients were assessed by traditional PFT and IOS. Diagnostic performance of IOS parameters to determine indication for patients of FEV1%pred < 50% was assessed on receiver-operating characteristics (ROC) curve analysis. Out of 215 patients, 18, 83, 78, and 36 patients were classified as grade 1, 2, 3, and 4, respectively, according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) severity grading. On Spearman correlation analysis, FEV1%pred, MMEF 75%–25%, and residual volume/total lung capacity (RV/TLC) correlated with total respiratory impedance (Z5)%pred, resistance at 5 Hz (R5)-resistance at 20 Hz (R20), R5-R20% R5, R5, R5%pred, frequency response (Fres), reactance area (Ax), and reactance at 5 Hz (X5). On ROC curve analysis, the area under the curve (AUC) of X5 absolute value, Fres, Ax, Z5%pred, R5-R20, and R5-R20% R5 were 0.748, 0.755, 0.760, 0.705, 0.715, and 0.735, respectively, for COPD patients who required inhalational glucocorticoid therapy. IOS parameters showed a good correlation with traditional pulmonary function parameters; reactance parameters showed a stronger correlation than that of the resistance parameters. IOS can be used as an alternative method for pulmonary function assessment in patients with COPD with FEV1%pred < 50% who need inhalational glucocorticoid therapy. Clinical trial registration number: ChiCTR-OCH-14004904. PMID:29145259

Useful marker of oscillatory lung function in methacholine challenge test-comparison of reactance and resistance with dose-response slope.

PubMed

Yoon, Jung Won; Shin, Youn Ho; Jee, Hye Mi; Chang, Sun Jung; Baek, Ji Hyeon; Choi, Sun Hee; Kim, Hyeong Yun; Han, Man Yong

2014-06-01

There are few studies focusing on the comparison of resistance (Rrs) and reactance (Xrs) in impulse oscillometry system (IOS) in the bronchial challenge test using dose-response slope (DRS), a quantitative index of bronchial hyperresponsiveness. We conducted a case-control study of 144 asthmatic and 218 non-asthmatic children to compare the diagnostic accuracy of two-point linear DRS for FEV1 , Rrs5 , and Xrs5 (DRS_FEV1 , DRS_Rrs5 , and DRS_Xrs5 ) and assessed various diagnostic cut-off points of provocation concentrations (PC) using receiver operating characteristic (ROC) curves. DRS_FEV1 had a stronger correlation with DRS_Xrs5 (r = 0.739, P < 0.001) than with DRS_Rrs5 (r = 0.652, P < 0.001) and the area under the ROC curves of DRS_Xrs5 (0.737) was similar to that of DRS_FEV1 (0.732) and higher than that of DRS_Rrs5 (0.668). The area under the ROC curves in order of greater value was as follows: absolute change of Xrs5 (Abs_Xrs5 ) (0.759) > percent change of FEV1 (Pch_FEV1 ) (0.735) > Pch_Xrs5 (0.727) > Abs_Rrs5 (0.690) > Pch_Rrs5 (0.630). PC78 _Xrs5 and PC0.17 _Xrs5 of IOS showed considerably good sensitivity and specificity comparable to those of PC20 _FEV1 by spirometry. Additional 18 (13%) children who showed normal spirometric measures were identified as asthmatics with the use of IOS. The utility of the DRS_Xrs5 to differentiate asthmatics from controls was comparable to that of the DRS_FEV1 and better than that of the DRS_Rrs5 . In addition, IOS could detect additional asthmatic patients who did not show positive responses in spirometry. © 2013 Wiley Periodicals, Inc.

Risk factors for persistence of lower respiratory symptoms among community members exposed to the 2001 World Trade Center terrorist attacks

PubMed Central

Jordan, Hannah T; Friedman, Stephen M; Reibman, Joan; Goldring, Roberta M; Miller Archie, Sara A; Ortega, Felix; Alper, Howard; Shao, Yongzhao; Maslow, Carey B; Cone, James E; Farfel, Mark R; Berger, Kenneth I

2017-01-01

Objectives We studied the course of lower respiratory symptoms (LRS; cough, wheeze or dyspnoea) among community members exposed to the 9/11/2001 World Trade Center (WTC) attacks during a period of 12–13 years following the attacks, and evaluated risk factors for LRS persistence, including peripheral airway dysfunction and post-traumatic stress disorder (PTSD). Methods Non-smoking adult participants in a case-control study of post-9/11-onset LRS (exam 1, 2008–2010) were recruited for follow-up (exam 2, 2013–2014). Peripheral airway function was assessed with impulse oscillometry measures of R5 and R5-20. Probable PTSD was a PTSD checklist score ≥44 on a 2006–2007 questionnaire. Results Of 785 exam 1 participants, 545 (69%) completed exam 2. Most (321, 59%) were asymptomatic at all assessments. Among 192 participants with initial LRS, symptoms resolved for 110 (57%) by exam 2, 55 (29%) had persistent LRS and 27 (14%) had other patterns. The proportion with normal spirometry increased from 65% at exam 1 to 85% at exam 2 in the persistent LRS group (p<0.01) and was stable among asymptomatic participants and those with resolved LRS. By exam 2, spirometry results did not differ across symptom groups; however, R5 and R5-20 abnormalities were more common among participants with persistent LRS (56% and 46%, respectively) than among participants with resolved LRS (30%, p<0.01; 27%, p=0.03) or asymptomatic participants (20%, p<0.001; 8.2%, p<0.001). PTSD, R5 at exam 1, and R5-20 at exam 1 were each independently associated with persistent LRS. Conclusions Peripheral airway dysfunction and PTSD may contribute to LRS persistence. Assessment of peripheral airway function detected pulmonary damage not evident on spirometry. Mental and physical healthcare for survivors of complex environmental disasters should be coordinated carefully. PMID:28341697

The effect of body weight on distal airway function and airway inflammation.

PubMed

van de Kant, Kim D G; Paredi, Paolo; Meah, Sally; Kalsi, Harpal S; Barnes, Peter J; Usmani, Omar S

Obesity is a global health problem that adversely influences the respiratory system. We assessed the effects of body mass index (BMI) on distal airway function and airway inflammation. Impulse oscillometry (IOS) as a measure of distal airway function, together with spirometry, were assessed in adults with a range of different BMIs. Airway inflammation was assessed with the fraction of exhaled nitric oxide (FeNO) and participants exhaled at various exhalation flows to determine alveolar and bronchial NO. In total 34 subjects were enrolled in the study; 19 subjects had a normal BMI (18.50-24.99), whilst 15 subjects were overweight (BMI 25.00-29.99), or obese (BMI ≥30). All subjects had normal spirometry. However, IOS measures of airway resistance (R) at 5Hz, 20Hz and frequency dependence (R 5-20 ) were elevated in overweight/obese individuals, compared to subjects with a normal BMI (median (interquartile range)); 5Hz: 0.41 (0.37, 0.45) vs. 0.32 (0.30, 0.37)kPa/l/s; 20Hz: 0.34 (0.30, 0.37) vs. 0.30 (0.26, 0.33)kPa/l/s; R 5-20 : 0.06 (0.04, 0.11) vs. 0.03 (0.01, 0.05)kPa/l/s; p<0.05), whereas airway reactance at 20Hz was decreased in overweight/obese individuals (20Hz: 0.07 (0.03, 0.09) vs. 0.10 (0.07, 0.13)kPa/l/s, p=0.009; 5Hz: -0.12 (-0.15, -0.10) vs. -0.10 (-0.13, -0.09)kPa/l/s, p=0.07). In contrast, within-breath IOS measures (a sign of expiratory flow limitation) and FeNO inflammatory measures, did not differ between groups (p>0.05). Being overweight has significant effects on distal and central airway function as determined by IOS, which is not detected by spirometry. Obesity does not influence airway inflammation as measured by FeNO. IOS is a reliable technique to identify airway abnormalities in the presence of normal spirometry in overweight people. Copyright © 2015 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.

Pulse Oximeter Plethysmograph Estimate of Pulsus Paradoxus as a Measure of Acute Asthma Exacerbation Severity and Response to Treatment.

PubMed

Arnold, Donald H; Wang, Li; Hartert, Tina V

2016-03-01

Pulsus paradoxus is one of the few objective bedside measures of acute asthma exacerbation severity but is difficult to measure in tachypneic and tachycardic patients and in noisy clinical environments. Our primary objective was to examine whether pulse oximeter plethysmograph estimate of pulsus paradoxus (PEP) is associated with physiologic and symptom measures of acute exacerbation severity (airway resistance by impulse oscillometry [%IOS] and the Acute Asthma Intensity Research Score [AAIRS]). Secondary objectives were to validate the previous association of PEP with percent predicted forced expiratory volume in 1 second (%FEV1 ) and to examine associations of change of PEP with change of these outcomes after 2 hours of treatment. This was a secondary analysis of data from a prospective observational study of patients aged 5-17 years with acute asthma exacerbations. The predictor variable, PEP, was measured using a dedicated pulse oximeter and waveform analysis program. Outcome measures included the AAIRS, %IOS, and %FEV1 at baseline and after 2 hours of treatment. We examined associations of PEP with %IOS and the AAIRS at baseline using multiple linear regression models adjusted for age, sex, and race. As secondary analyses we similarly examined the association of PEP with %FEV1 at baseline and change of PEP with change of %IOS, the AAIRS, and %FEV1 after 2 hours of treatment using multiple linear regression models adjusted for the baseline value of the outcome measure and the AAIRS. Among 684 participants (61% males; 61% African American) there were associations of baseline PEP with %IOS, the AAIRS, and %FEV1 (p < 0.001). Change of PEP after 2 hours of treatment was associated with change of %FEV1 (p < 0.001) and change of the AAIRS (p = 0.01) but not with change of %IOS (p = 0.60). PEP demonstrates criterion validity in predicting baseline %IOS, the AAIRS, and %FEV1 , and responsiveness to change of the AAIRS and %FEV1 . Data contained in the oximeter plethysmograph waveform might be utilized as a continuous, objective measure of acute asthma exacerbation severity and real-time response to treatment. © 2016 by the Society for Academic Emergency Medicine.

Reference Values of Impulse Oscillometric Lung Function Indices in Adults of Advanced Age

PubMed Central

Schulz, Holger; Flexeder, Claudia; Behr, Jürgen; Heier, Margit; Holle, Rolf; Huber, Rudolf M.; Jörres, Rudolf A.; Nowak, Dennis; Peters, Annette; Wichmann, H.-Erich; Heinrich, Joachim; Karrasch, Stefan

2013-01-01

Background Impulse oscillometry (IOS) is a non-demanding lung function test. Its diagnostic use may be particularly useful in patients of advanced age with physical or mental limitations unable to perform spirometry. Only few reference equations are available for Caucasians, none of them covering the old age. Here, we provide reference equations up to advanced age and compare them with currently available equations. Methods IOS was performed in a population-based sample of 1990 subjects, aged 45–91 years, from KORA cohorts (Augsburg, Germany). From those, 397 never-smoking, lung healthy subjects with normal spirometry were identified and sex-specific quantile regression models with age, height and body weight as predictors for respiratory system impedance, resistance, reactance, and other parameters of IOS applied. Results Women (n = 243) showed higher resistance values than men (n = 154), while reactance at low frequencies (up to 20 Hz) was lower (p<0.05). A significant age dependency was observed for the difference between resistance values at 5 Hz and 20 Hz (R5–R20), the integrated area of low-frequency reactance (AX), and resonant frequency (Fres) in both sexes whereas reactance at 5 Hz (X5) was age dependent only in females. In the healthy subjects (n = 397), mean differences between observed values and predictions for resistance (5 Hz and 20 Hz) and reactance (5 Hz) ranged between −1% and 5% when using the present model. In contrast, differences based on the currently applied equations (Vogel & Smidt 1994) ranged between −34% and 76%. Regarding our equations the indices were beyond the limits of normal in 8.1% to 18.6% of the entire KORA cohort (n = 1990), and in 0.7% to 9.4% with the currently applied equations. Conclusions Our study provides up-to-date reference equations for IOS in Caucasians aged 45 to 85 years. We suggest the use of the present equations particularly in advanced age in order to detect airway dysfunction. PMID:23691036

Arterial stiffness in people with Type 2 diabetes and obstructive sleep apnoea.

PubMed

Hvelplund Kristiansen, M; Banghøj, A M; Laugesen, E; Tarnow, L

2018-05-15

To examine whether people with Type 2 diabetes with concurrent obstructive sleep apnoea have increased arterial stiffness as compared with people with Type 2 diabetes without obstructive sleep apnoea. In a study with a case-control design, 40 people with Type 2 diabetes and treatment-naïve moderate to severe obstructive sleep apnoea (Apnoea-Hypopnoea Index ≥15) and a control group of 31 people with Type 2 diabetes without obstructive sleep apnoea (Apnoea-Hypopnoea Index <5) were examined. Obstructive sleep apnoea status was evaluated using the ApneaLink ® + home-monitoring device (Resmed Inc., San Diego, CA, USA), providing the Apnoea-Hypopnoea Index scores. Arterial stiffness was assessed according to carotid-femoral pulse wave velocity using the Sphygmocor device and the oscillometric Mobil-O-Graph ® (I.E.M. GmbH, Stolberg, Germany). Carotid-femoral pulse wave velocity was not significantly different between participants with Type 2 diabetes with obstructive sleep apnoea and those without obstructive sleep apnoea (10.7±2.2 m/s vs 10.3±2.1 m/s; P=0.513), whereas oscillometric pulse wave velocity was significantly higher in participants with Type 2 diabetes with obstructive sleep apnoea than in those without obstructive sleep apnoea (9.5±1.0 m/s vs 8.6±1.4 m/s; P=0.002). In multiple regression analysis, age (P=0.002), gender (men; P=0.018) and HbA 1c (P=0.027) were associated with carotid-femoral pulse wave velocity, and systolic blood pressure (P=0.004) and age (P<0.001) were associated with oscillometric pulse wave velocity. After adjustment, presence of obstructive sleep apnoea was not independently associated with pulse wave velocity whether assessed by tonometry or oscillometry. In conclusion, the present study did not find an age- and blood pressure-independent association between moderate to severe obstructive sleep apnoea and arterial stiffness in non-sleepy people with Type 2 diabetes. (Clinical trial registration number: NCT02482584). © 2018 Diabetes UK.

Evaluation of pulmonary dysfunctions and acid–base imbalances induced by Chlamydia psittaci in a bovine model of respiratory infection

PubMed Central

2014-01-01

Background Chlamydia psittaci (Cp) is a respiratory pathogen capable of inducing acute pulmonary zoonotic disease (psittacosis) or persistent infection. To elucidate the pathogenesis of this infection, a translational large animal model was recently introduced by our group. This study aims at quantifying and differentiating pulmonary dysfunction and acid–base imbalances induced by Cp. Methods Forty-two calves were grouped in (i) animals inoculated with Cp (n = 21) and (ii) controls sham-inoculated with uninfected cell culture (n = 21). For pulmonary function testing, impulse oscillometry, capnography, and FRC (functional residual capacity) measurement were applied to spontaneously breathing animals. Variables of acid–base status were assessed in venous blood using both (i) traditional Henderson-Hasselbalch and (ii) strong ion approach. Results Both obstructive and restrictive pulmonary disorders were induced in calves experimentally inoculated with Cp. Although disorders in respiratory mechanics lasted for 8–11 days, the pattern of spontaneous breathing was mainly altered in the period of acute illness (until 4 days post inoculation, dpi). Expiration was more impaired than inspiration, resulting in elevated FRC. Ventilation was characterised by a reduction in tidal volume (−25%) combined with an increased percentage of dead space volume and a significant reduction of alveolar volume by 10%. Minute ventilation increased significantly (+50%) due to a compensatory doubling of respiratory rate. Hyperventilatory hypocapnia at 2–3 dpi resulted in slightly increased blood pH at 2 dpi. However, the acid–base equilibrium was additionally influenced by metabolic components, i.e. the systemic inflammatory response, all of which were detected with help of the strong ion theory. Decreased concentrations of albumin (2–10 dpi), a negative acute-phase marker, resulted in a decrease in the sum of non-volatile weak acids (Atot), revealing an alkalotic effect. This was counterbalanced by acidic effects of decreased strong ion difference (SID), mediated by the interplay between hypochloraemia (alkalotic effect) and hyponatraemia (acidic effect). Conclusions This bovine model was found to be suitable for studying pathophysiology of respiratory Cp infection and may help elucidating functional host-pathogen interactions in the mammalian lung. PMID:24517577

A new approach to assess COPD by identifying lung function break-points

PubMed Central

Eriksson, Göran; Jarenbäck, Linnea; Peterson, Stefan; Ankerst, Jaro; Bjermer, Leif; Tufvesson, Ellen

2015-01-01

Purpose COPD is a progressive disease, which can take different routes, leading to great heterogeneity. The aim of the post-hoc analysis reported here was to perform continuous analyses of advanced lung function measurements, using linear and nonlinear regressions. Patients and methods Fifty-one COPD patients with mild to very severe disease (Global Initiative for Chronic Obstructive Lung Disease [GOLD] Stages I–IV) and 41 healthy smokers were investigated post-bronchodilation by flow-volume spirometry, body plethysmography, diffusion capacity testing, and impulse oscillometry. The relationship between COPD severity, based on forced expiratory volume in 1 second (FEV1), and different lung function parameters was analyzed by flexible nonparametric method, linear regression, and segmented linear regression with break-points. Results Most lung function parameters were nonlinear in relation to spirometric severity. Parameters related to volume (residual volume, functional residual capacity, total lung capacity, diffusion capacity [diffusion capacity of the lung for carbon monoxide], diffusion capacity of the lung for carbon monoxide/alveolar volume) and reactance (reactance area and reactance at 5Hz) were segmented with break-points at 60%–70% of FEV1. FEV1/forced vital capacity (FVC) and resonance frequency had break-points around 80% of FEV1, while many resistance parameters had break-points below 40%. The slopes in percent predicted differed; resistance at 5 Hz minus resistance at 20 Hz had a linear slope change of −5.3 per unit FEV1, while residual volume had no slope change above and −3.3 change per unit FEV1 below its break-point of 61%. Conclusion Continuous analyses of different lung function parameters over the spirometric COPD severity range gave valuable information additional to categorical analyses. Parameters related to volume, diffusion capacity, and reactance showed break-points around 65% of FEV1, indicating that air trapping starts to dominate in moderate COPD (FEV1 =50%–80%). This may have an impact on the patient’s management plan and selection of patients and/or outcomes in clinical research. PMID:26508849

Effects of intravenous and topical laryngeal lidocaine on heart rate, mean arterial pressure and cough response to endotracheal intubation in dogs.

PubMed

Thompson, Kate R; Rioja, Eva

2016-07-01

To compare the effects of intravenous (IV) and topical laryngeal lidocaine on heart rate (HR), mean arterial pressure (MAP) and cough response to endotracheal intubation (ETI) in dogs. Prospective, randomized, blinded clinical study. Forty-two client-owned dogs (American Society of Anesthesiologists class I and II status) undergoing elective orthopaedic surgery. Dogs were randomized to three groups. Dogs in group SALIV received 0.1 mL kg(-1) IV saline. Dogs in group LIDIV received 2 mg kg(-1) IV 2% lidocaine. Dogs in group LIDTA received 0.4 mg kg(-1) topically sprayed laryngeal 2% lidocaine. All dogs were premedicated with methadone (0.2 mg kg(-1) IV). After 30 minutes, IV propofol was administered to abolish the lateral palpebral reflex and produce jaw relaxation. The allocated treatment was then administered and, after 30 seconds, further propofol was administered to abolish the medial palpebral reflex and facilitate ETI. HR and MAP were measured at four time-points using cardiac auscultation and automated oscillometry, respectively. The cough response at ETI was recorded. One-way anova and post hoc Tukey adjustment were used to analyse parametric data. The Kruskal-Wallis test was used to analyse non-parametric data. Odds ratios were calculated for the cough response. A p-value of ≤0.05 was considered to indicate statistical significance. In response to ETI, changes in MAP differed significantly between groups. In SALIV, MAP increased (4 ± 6 mmHg), whereas it decreased in LIDIV (6 ± 13 mmHg) (p = 0.013) and LIDTA (7 ± 11 mmHg) (p = 0.003). Dogs in SALIV were almost 10 times more likely to cough than dogs in LIDIV (odds ratio 9.75, 95% confidence interval 0.98-96.60; p = 0.05). In propofol-anaesthetized dogs, IV and topical laryngeal lidocaine attenuated the pressor response to ETI, whereas IV lidocaine reduced the cough response. © 2015 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

Blood pressure is reduced and insulin sensitivity increased in glucose-intolerant, hypertensive subjects after 15 days of consuming high-polyphenol dark chocolate.

PubMed

Grassi, Davide; Desideri, Giovambattista; Necozione, Stefano; Lippi, Cristina; Casale, Raffaele; Properzi, Giuliana; Blumberg, Jeffrey B; Ferri, Claudio

2008-09-01

Flavanols from chocolate appear to increase nitric oxide bioavailability, protect vascular endothelium, and decrease cardiovascular disease (CVD) risk factors. We sought to test the effect of flavanol-rich dark chocolate (FRDC) on endothelial function, insulin sensitivity, beta-cell function, and blood pressure (BP) in hypertensive patients with impaired glucose tolerance (IGT). After a run-in phase, 19 hypertensives with IGT (11 males, 8 females; 44.8 +/- 8.0 y) were randomized to receive isocalorically either FRDC or flavanol-free white chocolate (FFWC) at 100 g/d for 15 d. After a wash-out period, patients were switched to the other treatment. Clinical and 24-h ambulatory BP was determined by sphygmometry and oscillometry, respectively, flow-mediated dilation (FMD), oral glucose tolerance test, serum cholesterol and C-reactive protein, and plasma homocysteine were evaluated after each treatment phase. FRDC but not FFWC ingestion decreased insulin resistance (homeostasis model assessment of insulin resistance; P < 0.0001) and increased insulin sensitivity (quantitative insulin sensitivity check index, insulin sensitivity index (ISI), ISI(0); P < 0.05) and beta-cell function (corrected insulin response CIR(120); P = 0.035). Systolic (S) and diastolic (D) BP decreased (P < 0.0001) after FRDC (SBP, -3.82 +/- 2.40 mm Hg; DBP, -3.92 +/- 1.98 mm Hg; 24-h SBP, -4.52 +/- 3.94 mm Hg; 24-h DBP, -4.17 +/- 3.29 mm Hg) but not after FFWC. Further, FRDC increased FMD (P < 0.0001) and decreased total cholesterol (-6.5%; P < 0.0001), and LDL cholesterol (-7.5%; P < 0.0001). Changes in insulin sensitivity (Delta ISI - Delta FMD: r = 0.510, P = 0.001; Delta QUICKI - Delta FMD: r = 0.502, P = 0.001) and beta-cell function (Delta CIR(120) - Delta FMD: r = 0.400, P = 0.012) were directly correlated with increases in FMD and inversely correlated with decreases in BP (Delta ISI - Delta 24-h SBP: r = -0.368, P = 0.022; Delta ISI - Delta 24-h DBP r = -0.384, P = 0.017). Thus, FRDC ameliorated insulin sensitivity and beta-cell function, decreased BP, and increased FMD in IGT hypertensive patients. These findings suggest flavanol-rich, low-energy cocoa food products may have a positive impact on CVD risk factors.

The prevalence of ocular lesions associated with hypertension in a population of geriatric cats in Auckland, New Zealand.

PubMed

Carter, J M; Irving, A C; Bridges, J P; Jones, B R

2014-01-01

To provide an estimate of the prevalence of ocular lesions associated with hypertension in geriatric cats in Auckland, New Zealand and to evaluate the importance of examination of the ocular fundi of cats over eight years of age. A total of 105 cats ≥8 years of age were examined and clinical signs recorded. Blood was collected for the laboratory measurement of the concentrations of blood urea nitrogen (BUN), glucose and creatinine in serum, urine was collected for determination of urine specific gravity (USG), and blood pressure (BP) was measured using high definition oscillometry equipment. A cat was determined to have systemic hypertension with a systolic BP ≥160 mm Hg and a diastolic BP ≥100 mm Hg. Each animal had an ocular fundic examination using a retinal camera to diagnose ocular lesions associated with hypertension, including retinopathies, choroidopathies and optic neuropathies. Blood pressure was successfully recorded in 73 cats. Of these, 37 (51%) had no hypertensive ocular lesions and no underlying disease diagnosed, 24 (33%) had no hypertensive ocular lesions detected, but underlying disease such as chronic kidney disease, hyperthyroidism or diabetes mellitus was diagnosed, and 12 (16%) cats had evidence of hypertensive ocular lesions. Ten of the cats with hypertensive ocular lesions were hypertensive at the time of the first visit and two were normotensive. One additional cat had hypertensive ocular lesions, but it was not possible to obtain consistent BP readings in this animal. Chronic kidney disease was the most commonly diagnosed concurrent disease in cats with hypertensive ocular lesions (n=6). Mean systolic BP for cats with hypertensive ocular lesions (168.0 (SE 6.29) mm Hg) was higher than for those with no ocular lesions (144.7 (SE 3.11) mm Hg) or those with no lesions but with underlying disease (146.0 (SE 4.97) mm Hg) (p=0.001). Ocular fundic examination of cats over eight years of age allows identification of cats with hypertensive ocular lesions, often before the owner or veterinarian is aware the cat has a problem with its vision. This may result in diagnosis of systemic hypertension allowing early treatment and resolution of lesions. The current study demonstrates that ocular lesions resulting from hypertension occur frequently enough in cats in Auckland to support the recommendation for fundic examination in cats over eight years of age as part of the routine physical examination.

Capillary refill time is an unreliable indicator of cardiovascular status in term neonates.

PubMed

LeFlore, Judy L; Engle, William D

2005-06-01

Decisions regarding the need for volume replacement in neonates often are made in the immediate newborn period. Capillary refill time (CRT) is used as an indicator of circulatory status; however, recent data show that CRT varies considerably with age, ambient and skin temperature, anatomical site of measurement, and duration of pressure. The purpose of this study was to (1) examine the relationship between CRT and heart rate (HR) and blood pressure (BP) in term neonates, and (2) evaluate the differences among CRT values measured at 3 body sites and with varying duration of cutaneous pressure. This was a prospective, cross-sectional, correlational study. Subjects Forty-two appropriate-weight-for-gestational-age (AGA) neonates with birthweights, (M = 3407; SD = +/- 540 g), gestational ages (M = 39 weeks; SD = +/- 1 week), and sex (21 males, 21 females). Infants had no history of perinatal distress or maternal chorioamnionitis. Each neonate was studied prospectively 1 to 4 hours after birth. The infants were clothed with only a diaper and evaluated on a radiant warmer bed set to achieve an axillary temperature of 36.5 degrees to 37.0 degrees C. Capillary refill time was measured with a digital stopwatch at 3 sites: volar surface of finger (F), plantar surface of heel (H), and lower sternum (St), using brief (1- to 2-second) and extended (3- to 4-second) pressure. Heart rate was auscultated and counted for 60 seconds, and BP was measured by oscillometry. Relationships among variables were assessed by Pearson correlation coefficient, analysis of variance, and multiple regression analysis. The Bonferroni correction for multiple comparisons was applied. Capillary refill time, blood pressure, and heart rate. There was no significant site variation for CRT for either brief (2.4 +/- 0.6 to 2.9 +/- 1.0 seconds) or extended (3.8 +/- 0.8 to 4.3 +/- 0.8 seconds) pressure. However, regardless of site, CRT was greater when extended versus brief pressure was used (P < 0.001). There were no significant correlations between HR and CRT. There was a moderate, direct relationship between BP and CRT observed in the following anatomic sites: (1) sternum/extended pressure and systolic BP (SBP), diastolic BP, and mean BP (r = 0.35, P = 0.02; r = 0.49, P = 0.001; and r = 0.43, P = 0.005, respectively); (2) sternum/brief pressure and SBP (r = 0.31, P = 0.05); and (3) finger/extended pressure and SBP (r = 0.30, P = 0.05). An unanticipated moderate, direct correlation between BP and CRT was observed; prolongation of CRT occurred with elevated blood pressure. This finding may have been secondary to increased circulating vasoactive substances in the newborn period; measurement of these substances was beyond the scope of this study. In addition, CRT was highly dependent on the duration of cutaneous pressure, regardless of the site. These 2 findings indicate that CRT may be an unreliable indicator of cardiovascular status in the term neonate during the first 4 hours after birth.

Evaluating bronchodilator response in pediatric patients with post-infectious bronchiolitis obliterans: use of different criteria for identifying airway reversibility.

PubMed

Mattiello, Rita; Vidal, Paula Cristina; Sarria, Edgar Enrique; Pitrez, Paulo Márcio; Stein, Renato Tetelbom; Mocelin, Helena Teresinha; Fischer, Gilberto Bueno; Jones, Marcus Herbert; Pinto, Leonardo Araújo

2016-01-01

Post-infectious bronchiolitis obliterans (PIBO) is a clinical entity that has been classified as constrictive, fixed obstruction of the lumen by fibrotic tissue. However, recent studies using impulse oscillometry have reported bronchodilator responses in PIBO patients. The objective of this study was to evaluate bronchodilator responses in pediatric PIBO patients, comparing different criteria to define the response. We evaluated pediatric patients diagnosed with PIBO and treated at one of two pediatric pulmonology outpatient clinics in the city of Porto Alegre, Brazil. Spirometric parameters were measured in accordance with international recommendations. We included a total of 72 pediatric PIBO patients. The mean pre- and post-bronchodilator values were clearly lower than the reference values for all parameters, especially FEF25-75%. There were post-bronchodilator improvements. When measured as mean percent increases, FEV1 and FEF25-75%, improved by 11% and 20%, respectively. However, when the absolute values were calculated, the mean FEV1 and FEF25-75% both increased by only 0.1 L. We found that age at viral aggression, a family history of asthma, and allergy had no significant effects on bronchodilator responses. Pediatric patients with PIBO have peripheral airway obstruction that is responsive to treatment but is not completely reversible with a bronchodilator. The concept of PIBO as fixed, irreversible obstruction does not seem to apply to this population. Our data suggest that airway obstruction is variable in PIBO patients, a finding that could have major clinical implications. A bronquiolite obliterante pós-infecciosa (BOPI) é uma entidade clínica que tem sido classificada como obstrução fixa e constritiva do lúmen por tecido fibrótico. Entretanto, estudos recentes utilizando oscilometria de impulso relataram resposta ao broncodilatador em pacientes com BOPI. O objetivo deste estudo foi avaliar a resposta broncodilatadora em pacientes pediátricos com BOPI, comparando critérios diferentes para a definição da resposta. Foram avaliados pacientes pediátricos com diagnóstico de BOPI tratados em um de dois ambulatórios de pneumologia pediátrica na cidade de Porto Alegre (RS). Parâmetros espirométricos foram medidos de acordo com recomendações internacionais. Foram incluídos 72 pacientes pediátricos com BOPI no estudo. As médias dos valores pré- e pós-broncodilatador foram claramente inferiores aos valores de referência para todos os parâmetros, especialmente FEF25-75%. Houve uma melhora pós-broncodilatador. Quando medidos como aumentos percentuais médios, VEF1 e FEF25-75% melhoraram em 11% e 20%, respectivamente. Entretanto, quando os valores absolutos foram calculados, as médias de VEF1 e FEF25-75% aumentaram somente em 0,1 l. Verificamos que a idade da agressão viral, história familiar de asma e alergia não tiveram efeitos significativos na resposta ao broncodilatador. Pacientes pediátricos com BOPI têm uma obstrução das vias aéreas periféricas que responde ao tratamento, mas não uma reversão completa com o broncodilatador. O conceito de BOPI como obstrução fixa e irreversível parece não se aplicar a essa população. Nossos dados sugerem que a obstrução de vias aéreas em pacientes com BOPI é variável, e esse achado pode ter importantes implicações clínicas.

Ankle brachial index for the diagnosis of lower limb peripheral arterial disease.

PubMed

Crawford, Fay; Welch, Karen; Andras, Alina; Chappell, Francesca M

2016-09-14

Peripheral arterial disease (PAD) of the lower limb is common, with prevalence of both symptomatic and asymptomatic disease estimated at 13% in the over 50 age group. Symptomatic PAD affects about 5% of individuals in Western populations between the ages of 55 and 74 years. The most common initial symptom of PAD is muscle pain on exercise that is relieved by rest and is attributed to reduced lower limb blood flow due to atherosclerotic disease (intermittent claudication). The ankle brachial index (ABI) is widely used by a variety of healthcare professionals, including specialist nurses, physicians, surgeons and podiatrists working in primary and secondary care settings, to assess signs and symptoms of PAD. As the ABI test is non-invasive and inexpensive and is in widespread clinical use, a systematic review of its diagnostic accuracy in people presenting with leg pain suggestive of PAD is highly relevant to routine clinical practice. To estimate the diagnostic accuracy of the ankle brachial index (ABI) - also known as the ankle brachial pressure index (ABPI) - for the diagnosis of peripheral arterial disease in people who experience leg pain on walking that is alleviated by rest. We carried out searches of the following databases in August 2013: MEDLINE (Ovid SP),Embase (Ovid SP), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (EBSCO), Latin American and Caribbean Health Sciences (LILACS) (Bireme), Database of Abstracts of Reviews of Effects and the Health Technology Assessment Database in The Cochrane Library, the Institute for Scientific Information (ISI) Conference Proceedings Citation Index - Science, the British Library Zetoc Conference search and Medion. We included cross-sectional studies of ABI in which duplex ultrasonography or angiography was used as the reference standard. We also included cross-sectional or diagnostic test accuracy (DTA) cohort studies consisting of both prospective and retrospective studies.Participants were adults presenting with leg pain on walking that was relieved by rest, who were tested in primary care settings or secondary care settings (hospital outpatients only) and who did not have signs or symptoms of critical limb ischaemia (rest pain, ischaemic ulcers or gangrene).The index test was ABI, also called the ankle brachial pressure index (ABPI) or the Ankle Arm Index (AAI), which was performed with a hand-held doppler or oscillometry device to detect ankle vessels. We included data collected via sphygmomanometers (both manual and aneroid) and digital equipment. Two review authors independently replicated data extraction by using a standard form, which included an assessment of study quality, and resolved disagreements by discussion. Two review authors extracted participant-level data when available to populate 2×2 contingency tables (true positives, true negatives, false positives and false negatives).After a pilot phase involving two review authors working independently, we used the methodological quality assessment tool the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2), which incorporated our review question - along with a flow diagram to aid reviewers' understanding of the conduct of the study when necessary and an assessment of risk of bias and applicability judgements. We screened 17,055 records identified through searches of databases. We obtained 746 full-text articles and assessed them for relevance. We scrutinised 49 studies to establish their eligibility for inclusion in the review and excluded 48, primarily because participants were not patients presenting solely with exertional leg pain, investigators used no reference standard or investigators used neither angiography nor duplex ultrasonography as the reference standard. We excluded most studies for more than one reason.Only one study met the eligibility criteria and provided limb-level accuracy data from just 85 participants (158 legs). This prospective study compared the manual doppler method of obtaining an ABI (performed by untrained personnel) with the automated oscillometric method. Limb-level data, as reported by the study, indicated that the accuracy of the ABI in detecting significant arterial disease on angiography is superior when stenosis is present in the femoropopliteal vessels, with sensitivity of 97% (95% confidence interval (CI) 93% to 99%) and specificity of 89% (95% CI 67% to 95%) for oscillometric ABI, and sensitivity of 95% (95% CI 89% to 97%) and specificity of 56% (95% CI 33% to 70%) for doppler ABI. The ABI threshold was not reported. Investigators attributed the lower specificity for doppler to the fact that a tibial or dorsalis pedis pulse could not be detected by doppler in 12 of 27 legs with normal vessels or non-significant lesions. The superiority of the oscillometric (automated) method for obtaining an ABI reading over the manual method with a doppler probe used by inexperienced operators may be a clinically important finding. Evidence about the accuracy of the ankle brachial index for the diagnosis of PAD in people with leg pain on exercise that is alleviated by rest is sparse. The single study included in our review provided only limb-level data from a few participants. Well-designed cross-sectional studies are required to evaluate the accuracy of ABI in patients presenting with early symptoms of peripheral arterial disease in all healthcare settings. Another systematic review of existing studies assessing the use of ABI in alternative patient groups, including asymptomatic, high-risk patients, is required.

Twenty-Four-Hour Ambulatory Blood Pressure Monitoring in Hypertension

PubMed Central

2012-01-01

Executive Summary Objective The objective of this health technology assessment was to determine the clinical effectiveness and cost-effectiveness of 24-hour ambulatory blood pressure monitoring (ABPM) for hypertension. Clinical Need: Condition and Target Population Hypertension occurs when either systolic blood pressure, the pressure in the artery when the heart contracts, or diastolic blood pressure, the pressure in the artery when the heart relaxes between beats, are consistently high. Blood pressure (BP) that is consistently more than 140/90 mmHg (systolic/diastolic) is considered high. A lower threshold, greater than 130/80 mmHg (systolic/diastolic), is set for individuals with diabetes or chronic kidney disease. In 2006 and 2007, the age-standardized incidence rate of diagnosed hypertension in Canada was 25.8 per 1,000 (450,000 individuals were newly diagnosed). During the same time period, 22.7% of adult Canadians were living with diagnosed hypertension. A smaller proportion of Canadians are unaware they have hypertension; therefore, the estimated number of Canadians affected by this disease may be higher. Diagnosis and management of hypertension are important, since elevated BP levels are related to the risk of cardiovascular disease, including stroke. In Canada in 2003, the costs to the health care system related to the diagnosis, treatment, and management of hypertension were over $2.3 billion (Cdn). Technology The 24-hour ABPM device consists of a standard inflatable cuff attached to a small computer weighing about 500 grams, which is worn over the shoulder or on a belt. The technology is noninvasive and fully automated. The device takes BP measurements every 15 to 30 minutes over a 24-to 28-hour time period, thus providing extended, continuous BP recordings even during a patient’s normal daily activities. Information on the multiple BP measurements can be downloaded to a computer. The main detection methods used by the device are auscultation and oscillometry. The device avoids some of the pitfalls of conventional office or clinic blood pressure monitoring (CBPM) using a cuff and mercury sphygmomanometer such as observer bias (the phenomenon of measurement error when the observer overemphasizes expected results) and white coat hypertension (the phenomenon of elevated BP when measured in the office or clinic but normal BP when measured outside of the medical setting). Research Questions Is there a difference in patient outcome and treatment protocol using 24-hour ABPM versus CBPM for uncomplicated hypertension? Is there a difference between the 2 technologies when white coat hypertension is taken into account? What is the cost-effectiveness and budget impact of 24-hour ABPM versus CBPM for uncomplicated hypertension? Research Methods Literature Search Search Strategy A literature search was performed on August 4, 2011 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA) for studies published from January 1, 1997 to August 4, 2011. Abstracts were reviewed by a single reviewer. For those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists were also examined for any additional relevant studies not identified through the search. Articles with unknown eligibility were reviewed with a second clinical epidemiologist and then a group of epidemiologists until consensus was established. The quality of evidence was assessed as high, moderate, low, or very low according to GRADE methodology. Inclusion Criteria English language articles; published between January 1, 1997 and August 4, 2011; adults aged 18 years of age or older; journal articles reporting on the effectiveness, cost-effectiveness, or safety for the comparison of interest; clearly described study design and methods; health technology assessments, systematic reviews, meta-analyses, or randomized controlled trials. Exclusion Criteria non-English papers; animal or in vitro studies; case reports, case series, or case-case studies; studies comparing different antihypertensive therapies and evaluating their antihypertensive effects using 24-hour ABPM; studies on home or self-monitoring of BP, and studies on automated office BP measurement; studies in high-risk subgroups (e.g. diabetes, pregnancy, kidney disease). Outcomes of Interest Patient Outcomes mortality: all cardiovascular events (e.g., myocardial infarction [MI], stroke); non-fatal: all cardiovascular events (e.g., MI, stroke); combined fatal and non-fatal: all cardiovascular events (e.g., MI, stroke); all non-cardiovascular events; control of BP (e.g. systolic and/or diastolic target level). Drug-Related Outcomes percentage of patients who show a reduction in, or stop, drug treatment; percentage of patients who begin multi-drug treatment; drug therapy use (e.g. number, intensity of drug use); drug-related adverse events. Quality of Evidence The quality of the body of evidence was assessed as high, moderate, low, or very low according to the GRADE Working Group criteria. As stated by the GRADE Working Group, the following definitions of quality were used in grading the quality of the evidence: High Further research is very unlikely to change confidence in the estimate of effect. Moderate Further research is likely to have an important impact on confidence in the estimate of effect and may change the estimate. Low Further research is very likely to have an important impact on confidence in the estimate of effect and is likely to change the estimate. Very Low Any estimate of effect is very uncertain. Summary of Findings Short-Term Follow-Up Studies (Length of Follow-Up of ≤ 1 Year) Based on very low quality of evidence, there is no difference between technologies for non-fatal cardiovascular events. Based on moderate quality of evidence, ABPM resulted in improved BP control among patients with sustained hypertension compared to CBPM. Based on low quality of evidence, ABPM resulted in hypertensive patients being more likely to stop antihypertensive therapy and less likely to proceed to multi-drug therapy compared to CBPM. Based on low quality of evidence, there is a beneficial effect of ABPM on the intensity of antihypertensive drug use compared to CBPM. Based on moderate quality of evidence, there is no difference between technologies in the number of antihypertensive drugs used. Based on low to very low quality of evidence, there is no difference between technologies in the risk for a drug-related adverse event or noncardiovascular event. Long-Term Follow-Up Study (Mean Length of Follow-Up of 5 Years) Based on moderate quality of evidence, there is a beneficial effect of ABPM on total combined cardiovascular events compared to CBPM. Based on low quality of evidence, there is a lack of a beneficial effect of ABPM on nonfatal cardiovascular events compared to CBPM; however, the lack of a beneficial effect is based on a borderline result. Based on low quality of evidence, there is no beneficial effect of ABPM on fatal cardiovascular events compared to CBPM. Based on low quality of evidence, there is no difference between technologies for the number of patients who began multi-drug therapy. Based on low quality of evidence, there is a beneficial effect of CBPM on control of BP compared to ABPM. This result is in the opposite direction than expected. Based on moderate quality of evidence, there is no difference between technologies in the risk for a drug-related adverse event. PMID:23074425