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Sample records for lung ventilation scintigraphy

  1. Potential Role of Lung Ventilation Scintigraphy in the Assessment of COPD

    PubMed Central

    Cukic, Vesna; Begic, Amela

    2014-01-01

    Objective: To highlight the importance of the lung ventilation scintigraphy (LVS) to study the regional distribution of lung ventilation and to describe most frequent abnormal patterns of lung ventilation distribution obtained by this technique in COPD and to compare the information obtained by LVS with the that obtained by traditional lung function tests. Material and methods: The research was done in 20 patients with previously diagnosed COPD who were treated in Intensive care unit of Clinic for pulmonary diseases and TB “Podhrastovi” Clinical Center, University of Sarajevo in exacerbation of COPD during first three months of 2014. Each patient was undergone to testing of pulmonary function by body plethysmography and ventilation/perfusion lung scintigraphy with radio pharmaceutics Technegas, 111 MBq Tc -99m-MAA. We compared the results obtained by these two methods. Results: All patients with COPD have a damaged lung function tests examined by body plethysmography implying airflow obstruction, but LVS indicates not only airflow obstruction and reduced ventilation, but also indicates the disorders in distribution in lung ventilation. Conclusion: LVS may add further information to the functional evaluation of COPD to that provided by traditional lung function tests and may contribute to characterizing the different phenotypes of COPD. PMID:25132709

  2. Ventilation-perfusion scintigraphy in an adult with congenital unilateral hyperlucent lung

    SciTech Connect

    Wegener, W.A.; Velchik, M.G. )

    1990-10-01

    A variety of congenital and acquired etiologies can give rise to the radiographic finding of a unilateral hyperlucent lung. An unusual case of congenital lobar emphysema diagnosed in a young adult following the initial discovery of a hyperexpanded, hyperlucent lung is reported. Although subsequent bronchoscopy and radiologic studies detailed extensive anatomic abnormalities, functional imaging also played an important role in arriving at this rare diagnosis. In particular, ventilation-perfusion scintigraphy identified the small contralateral lung as the functional lung and helped narrow the differential diagnosis to etiologies involving obstructive airway disorders.

  3. Lung scintigraphy in differential diagnosis of peripheral lung cancer and community-acquired pneumonia

    NASA Astrophysics Data System (ADS)

    Krivonogov, Nikolay G.; Efimova, Nataliya Y.; Zavadovsky, Konstantin W.; Lishmanov, Yuri B.

    2016-08-01

    Ventilation/perfusion lung scintigraphy was performed in 39 patients with verified diagnosis of community-acquired pneumonia (CAP) and in 14 patients with peripheral lung cancer. Ventilation/perfusion ratio, apical-basal gradients of ventilation (U/L(V)) and lung perfusion (U/L(P)), and alveolar capillary permeability of radionuclide aerosol were determined based on scintigraphy data. The study demonstrated that main signs of CAP were increases in ventilation/perfusion ratio, perfusion and ventilation gradient on a side of the diseased lung, and two-side increase in alveolar capillary permeability rate for radionuclide aerosol. Unlike this, scintigraphic signs of peripheral lung cancer comprise an increase in ventilation/perfusion ratio over 1.0 on a side of the diseased lung with its simultaneous decrease on a contralateral side, normal values of perfusion and ventilation gradients of both lungs, and delayed alveolar capillary clearance in the diseased lung compared with the intact lung.

  4. Dynamic ventilation scintigraphy: a comparison of parameter estimation gating models.

    PubMed

    Hack, S N; Paoni, R A; Stratton, H; Valvano, M; Line, B R; Cooper, J A

    1988-11-01

    Two procedures for providing the synchronization of ventilation scintigraphic data to create dynamic displays of the pulmonary cycle are described and compared. These techniques are based on estimating instantaneous lung volume by pneumotachometry and by scintigraphy. Twenty-three patients were studied by these two techniques. The results indicate that the estimation of the times of end-inspiration and end-expiration are equivalent by the two techniques but the morphologies of the two estimated time-volume waveforms are not equivalent. Ventilation cinescintigraphy based on time division gating but not on isovolume division gating can be equivalently generated from list mode acquired data by employing either technique described.

  5. Solubilized xenon 133 lung scintigraphy

    SciTech Connect

    Oates, E.; Sarno, R.C.

    1988-11-01

    Lung scanning using solubilized xenon 133 can provide important information concerning both pulmonary perfusion and ventilation. This technique proved valuable in establishing the diagnosis of congenital lobar emphysema in a 7-month-old baby.

  6. Estimation of Lung Ventilation

    NASA Astrophysics Data System (ADS)

    Ding, Kai; Cao, Kunlin; Du, Kaifang; Amelon, Ryan; Christensen, Gary E.; Raghavan, Madhavan; Reinhardt, Joseph M.

    Since the primary function of the lung is gas exchange, ventilation can be interpreted as an index of lung function in addition to perfusion. Injury and disease processes can alter lung function on a global and/or a local level. MDCT can be used to acquire multiple static breath-hold CT images of the lung taken at different lung volumes, or with proper respiratory control, 4DCT images of the lung reconstructed at different respiratory phases. Image registration can be applied to this data to estimate a deformation field that transforms the lung from one volume configuration to the other. This deformation field can be analyzed to estimate local lung tissue expansion, calculate voxel-by-voxel intensity change, and make biomechanical measurements. The physiologic significance of the registration-based measures of respiratory function can be established by comparing to more conventional measurements, such as nuclear medicine or contrast wash-in/wash-out studies with CT or MR. An important emerging application of these methods is the detection of pulmonary function change in subjects undergoing radiation therapy (RT) for lung cancer. During RT, treatment is commonly limited to sub-therapeutic doses due to unintended toxicity to normal lung tissue. Measurement of pulmonary function may be useful as a planning tool during RT planning, may be useful for tracking the progression of toxicity to nearby normal tissue during RT, and can be used to evaluate the effectiveness of a treatment post-therapy. This chapter reviews the basic measures to estimate regional ventilation from image registration of CT images, the comparison of them to the existing golden standard and the application in radiation therapy.

  7. Lung Ventilation/Perfusion Scan

    MedlinePlus

    ... from the NHLBI on Twitter. What Is a Lung Ventilation/Perfusion Scan? A lung ventilation/perfusion scan, or VQ scan, is a ... that measures air and blood flow in your lungs. A VQ scan most often is used to ...

  8. Deep Vein Thrombosis Presenting on Pulmonary Ventilation and Perfusion Scintigraphy.

    PubMed

    Itani, Malak; Fair, Joanna; Hillman, Zachary; Behnia, Fatemeh; Elojeimy, Saeed

    2016-10-01

    A 52-year-old woman presenting with dyspnea was referred for a ventilation and perfusion scan (VQ). VQ images (with Tc-DTPA [diethylene triamine pentaacetic acid aerosol] and Tc-MAA [macroaggregated albumin]) initially appeared normal; however, count rates on perfusion images were similar to ventilation images, implying little Tc-MAA had reached the lungs. Spot images of the injected extremity demonstrated focal Tc-MAA accumulation worrisome for a venous thrombus, subsequently confirmed by Doppler ultrasound. Careful attention to relative radiotracer count rates on VQ scans is crucial to ensure diagnostic utility. In addition, abnormal low perfusion radiotracer counts may unveil other pathology with important clinical implications. PMID:27556796

  9. Regional distribution of ventilation assessed by Kr-81m scintigraphy employing temporal Fourier transform

    SciTech Connect

    Slosman, D.; Susskind, H.; Cinotti, L.; van Giessen, J.W.; Brill, A.B.

    1986-01-01

    Temporal Fourier analysis was applied to Kr-81m ventilation scintigraphy to determine the amplitude (AMP1) and phase (PHA1) of the first harmonic of a single composite respiratory cycle and to compare regional patterns in subjects with obstructive pulmonary disease (COPD) and nonobstructed subjects. Six nonobstructed subjects, three subjects with small airway disease, six subjects with COPD, and one subject with restrictive disease were investigated. The mean value of the functional PHA1 image (PHA1m) correlated negatively with 1-second forced expiratory volume (FEV1) (r = -0.801, P less than .001), with %FEV1/FVC (r = -0.636, P less than .01) and maximum midexpiratory flow rate (FEF25-75%) (r = -0.723, P less than .002), and correlated positively with residual volume (r = 0.640, P less than .01). PHA1m values for the six subjects with COPD were significantly higher (t = 2.359, P less than .05) than for the ten nonobstructed subjects. Display of phase and amplitude functional images permits a visual evaluation of the regional distribution of ventilation to be made. Regional abnormalities of air flow were detected in obstructed subjects, and the presence of airway obstruction could be predicted. Dynamic ventilation imaging, therefore, appears to be a potentially useful noninvasive technique to assess lung impairment on a localized level.

  10. Metformin attenuates ventilator-induced lung injury

    PubMed Central

    2012-01-01

    Introduction Diabetic patients may develop acute lung injury less often than non-diabetics; a fact that could be partially ascribed to the usage of antidiabetic drugs, including metformin. Metformin exhibits pleiotropic properties which make it potentially beneficial against lung injury. We hypothesized that pretreatment with metformin preserves alveolar capillary permeability and, thus, prevents ventilator-induced lung injury. Methods Twenty-four rabbits were randomly assigned to pretreatment with metformin (250 mg/Kg body weight/day per os) or no medication for two days. Explanted lungs were perfused at constant flow rate (300 mL/min) and ventilated with injurious (peak airway pressure 23 cmH2O, tidal volume ≈17 mL/Kg) or protective (peak airway pressure 11 cmH2O, tidal volume ≈7 mL/Kg) settings for 1 hour. Alveolar capillary permeability was assessed by ultrafiltration coefficient, total protein concentration in bronchoalveolar lavage fluid (BALF) and angiotensin-converting enzyme (ACE) activity in BALF. Results High-pressure ventilation of the ex-vivo lung preparation resulted in increased microvascular permeability, edema formation and microhemorrhage compared to protective ventilation. Compared to no medication, pretreatment with metformin was associated with a 2.9-fold reduction in ultrafiltration coefficient, a 2.5-fold reduction in pulmonary edema formation, lower protein concentration in BALF, lower ACE activity in BALF, and fewer histological lesions upon challenge of the lung preparation with injurious ventilation. In contrast, no differences regarding pulmonary artery pressure and BALF total cell number were noted. Administration of metformin did not impact on outcomes of lungs subjected to protective ventilation. Conclusions Pretreatment with metformin preserves alveolar capillary permeability and, thus, decreases the severity of ventilator-induced lung injury in this model. PMID:22827994

  11. Perfusion Scintigraphy and Patient Selection for Lung Volume Reduction Surgery

    PubMed Central

    Chandra, Divay; Lipson, David A.; Hoffman, Eric A.; Hansen-Flaschen, John; Sciurba, Frank C.; DeCamp, Malcolm M.; Reilly, John J.; Washko, George R.

    2010-01-01

    Rationale: It is unclear if lung perfusion can predict response to lung volume reduction surgery (LVRS). Objectives: To study the role of perfusion scintigraphy in patient selection for LVRS. Methods: We performed an intention-to-treat analysis of 1,045 of 1,218 patients enrolled in the National Emphysema Treatment Trial who were non–high risk for LVRS and had complete perfusion scintigraphy results at baseline. The median follow-up was 6.0 years. Patients were classified as having upper or non–upper lobe–predominant emphysema on visual examination of the chest computed tomography and high or low exercise capacity on cardiopulmonary exercise testing at baseline. Low upper zone perfusion was defined as less than 20% of total lung perfusion distributed to the upper third of both lungs as measured on perfusion scintigraphy. Measurements and Main Results: Among 284 of 1,045 patients with upper lobe–predominant emphysema and low exercise capacity at baseline, the 202 with low upper zone perfusion had lower mortality with LVRS versus medical management (risk ratio [RR], 0.56; P = 0.008) unlike the remaining 82 with high perfusion where mortality was unchanged (RR, 0.97; P = 0.62). Similarly, among 404 of 1,045 patients with upper lobe–predominant emphysema and high exercise capacity, the 278 with low upper zone perfusion had lower mortality with LVRS (RR, 0.70; P = 0.02) unlike the remaining 126 with high perfusion (RR, 1.05; P = 1.00). Among the 357 patients with non–upper lobe–predominant emphysema (75 with low and 282 with high exercise capacity) there was no improvement in survival with LVRS and measurement of upper zone perfusion did not contribute new prognostic information. Conclusions: Compared with optimal medical management, LVRS reduces mortality in patients with upper lobe–predominant emphysema when there is low rather than high perfusion to the upper lung. PMID:20538961

  12. Perioperative lung protective ventilation in obese patients.

    PubMed

    Fernandez-Bustamante, Ana; Hashimoto, Soshi; Serpa Neto, Ary; Moine, Pierre; Vidal Melo, Marcos F; Repine, John E

    2015-01-01

    The perioperative use and relevance of protective ventilation in surgical patients is being increasingly recognized. Obesity poses particular challenges to adequate mechanical ventilation in addition to surgical constraints, primarily by restricted lung mechanics due to excessive adiposity, frequent respiratory comorbidities (i.e. sleep apnea, asthma), and concerns of postoperative respiratory depression and other pulmonary complications. The number of surgical patients with obesity is increasing, and facing these challenges is common in the operating rooms and critical care units worldwide. In this review we summarize the existing literature which supports the following recommendations for the perioperative ventilation in obese patients: (1) the use of protective ventilation with low tidal volumes (approximately 8 mL/kg, calculated based on predicted -not actual- body weight) to avoid volutrauma; (2) a focus on lung recruitment by utilizing PEEP (8-15 cmH2O) in addition to recruitment maneuvers during the intraoperative period, as well as incentivized deep breathing and noninvasive ventilation early in the postoperative period, to avoid atelectasis, hypoxemia and atelectrauma; and (3) a judicious oxygen use (ideally less than 0.8) to avoid hypoxemia but also possible reabsorption atelectasis. Obesity poses an additional challenge for achieving adequate protective ventilation during one-lung ventilation, but different lung isolation techniques have been adequately performed in obese patients by experienced providers. Postoperative efforts should be directed to avoid hypoventilation, atelectasis and hypoxemia. Further studies are needed to better define optimum protective ventilation strategies and analyze their impact on the perioperative outcomes of surgical patients with obesity. PMID:25907273

  13. Current role of lung scintigraphy in pulmonary embolism.

    PubMed

    Giordano, A; Angiolillo, D J

    2001-12-01

    The pivotal role of lung scintigraphy in the diagnosis of pulmonary embolism (PE) has been questioned in recent years due to the introduction of spiral computed tomography. However, the scintigraphic results used for comparisons are often those of the authoritative PIOPED (Prospective Investigation of Pulmonary Embolism Diagnosis) study, carried out in the 1980s. Pulmonary scintigraphy has progressed from those years both in the methodological and interpretative fields, although perhaps too slowly. Results better than those of PIOPED's have been presented by study groups who used: 1) perfusion-only approach, 2) SPET imaging; 3) new interpretative criteria; 4) different prediction rules to integrate clinical and scintigraphic probabilities of PE. These advances are still insufficiently recognised by the nuclear medicine community, possibly due to a sort of PIOPED-based "cultural globalisation". This paper reviews the actual advantages and limitations of nuclear medicine techniques, the diagnostic role of scintigraphy within the diagnostic algorithms proposed by international working groups and scientific societies and the results obtained from SPET imaging in the diagnosis of PE.

  14. Myocardial perfusion as assessed by thallium-201 scintigraphy during the discontinuation of mechanical ventilation in ventilator-dependent patients

    SciTech Connect

    Hurford, W.E.; Lynch, K.E.; Strauss, H.W.; Lowenstein, E.; Zapol, W.M. )

    1991-06-01

    Patients who cannot be separated from mechanical ventilation (MV) after an episode of acute respiratory failure often have coexisting coronary artery disease. The authors hypothesized that increased left ventricular (LV) wall stress during periods of spontaneous ventilation (SV) could alter myocardial perfusion in these patients. Using thallium-201 (201TI) myocardial scintigraphy, the authors studied the occurrence of myocardial perfusion abnormalities during periods of SV in 15 MV-dependent patients (nine women, six men; aged 71 {plus minus} 7 yr, mean {plus minus} SD). Fourteen of these patients were studied once with 201TI myocardial scintigraphy during intermittent mechanical ventilation (IMV) and again on another day, after at least 10 min of SV through a T-piece. One patient was studied during SV only. Thirteen of 14 of the patients (93%) studied during MV had abnormal patterns of initial myocardial 201TI uptake, but only 1 patient demonstrated redistribution of 201TI on delayed images. The remainder of the abnormalities observed during MV were fixed defects. SV produced significant alterations of myocardial 201TI distribution or transient LV dilation, or both, in 7 of the 15 patients (47%). Four patients demonstrated new regional decreases of LV myocardial thallium concentration with redistribution of the isotope on delayed images. The patient studied only during SV also had myocardial 201TI defects with redistribution. Five patients (3 also having areas of 201TI redistribution) had transient LV dilation during SV.

  15. PREOPERATIVE PREDICTION OF LUNG FUNCTION IN PNEUMONECTOMY BY SPIROMETRY AND LUNG PERFUSION SCINTIGRAPHY

    PubMed Central

    Cukic, Vesna

    2012-01-01

    Introduction: Nowadays an increasing number of lung resections are being done because of the rising prevalence of lung cancer that occurs mainly in patients with limited lung function, what is caused by common etiologic factor - smoking cigarettes. Loss of lung tissue in such patients can worsen much the postoperative pulmonary function. So it is necessary to asses the postoperative pulmonary function especially after maximal resection, i.e. pneumonectomy. Objective: To check over the accuracy of preoperative prognosis of postoperative lung function after pneumonectomy using spirometry and lung perfusion scinigraphy. Material and methods: The study was done on 17 patients operated at the Clinic for thoracic surgery, who were treated previously at the Clinic for Pulmonary Diseases “Podhrastovi” in the period from 01. 12. 2008. to 01. 06. 2011. Postoperative pulmonary function expressed as ppoFEV1 (predicted postoperative forced expiratory volume in one second) was prognosticated preoperatively using spirometry, i.e.. simple calculation according to the number of the pulmonary segments to be removed and perfusion lung scintigraphy. Results: There is no significant deviation of postoperative achieved values of FEV1 from predicted ones obtained by both methods, and there is no significant differences between predicted values (ppoFEV1) obtained by spirometry and perfusion scintigraphy. Conclusion: It is necessary to asses the postoperative pulmonary function before lung resection to avoid postoperative respiratory failure and other cardiopulmonary complications. It is absolutely necessary for pneumonectomy, i.e.. maximal pulmonary resection. It can be done with great possibility using spirometry or perfusion lung scintigraphy. PMID:23378687

  16. Lung isolation, one-lung ventilation and hypoxaemia during lung isolation

    PubMed Central

    Purohit, Atul; Bhargava, Suresh; Mangal, Vandana; Parashar, Vinod Kumar

    2015-01-01

    Lung isolation is being used more frequently in both adult and paediatric age groups due to increasing incidence of thoracoscopy and video-assisted thoracoscopic surgery in these patients. Various indications for lung isolation and one-lung ventilation include surgical and non-surgical reasons. Isolation can be achieved by double-lumen endotracheal tubes or bronchial blocker. Different issues arise in prone and semi-prone position. The management of hypoxia with lung isolation is a stepwise drill of adding inhaled oxygen, adding positive end-expiratory pressure to ventilated lung and continuous positive airway pressure to non-ventilated side. PMID:26556920

  17. History of Mechanical Ventilation. From Vesalius to Ventilator-induced Lung Injury.

    PubMed

    Slutsky, Arthur S

    2015-05-15

    Mechanical ventilation is a life-saving therapy that catalyzed the development of modern intensive care units. The origins of modern mechanical ventilation can be traced back about five centuries to the seminal work of Andreas Vesalius. This article is a short history of mechanical ventilation, tracing its origins over the centuries to the present day. One of the great advances in ventilatory support over the past few decades has been the development of lung-protective ventilatory strategies, based on our understanding of the iatrogenic consequences of mechanical ventilation such as ventilator-induced lung injury. These strategies have markedly improved clinical outcomes in patients with respiratory failure. PMID:25844759

  18. History of Mechanical Ventilation. From Vesalius to Ventilator-induced Lung Injury.

    PubMed

    Slutsky, Arthur S

    2015-05-15

    Mechanical ventilation is a life-saving therapy that catalyzed the development of modern intensive care units. The origins of modern mechanical ventilation can be traced back about five centuries to the seminal work of Andreas Vesalius. This article is a short history of mechanical ventilation, tracing its origins over the centuries to the present day. One of the great advances in ventilatory support over the past few decades has been the development of lung-protective ventilatory strategies, based on our understanding of the iatrogenic consequences of mechanical ventilation such as ventilator-induced lung injury. These strategies have markedly improved clinical outcomes in patients with respiratory failure.

  19. Ventilator-induced lung injury in preterm infants

    PubMed Central

    Carvalho, Clarissa Gutierrez; Silveira, Rita C; Procianoy, Renato Soibelmann

    2013-01-01

    In preterm infants, the need for intubation and mechanical ventilation is associated with ventilator-induced lung injuries and subsequent bronchopulmonary dysplasia. The aim of the present review was to improve the understanding of the mechanisms of injury that involve cytokine-mediated inflammation to contribute to the development of new preventive strategies. Relevant articles were retrieved from the PubMed database using the search terms "ventilator-induced lung injury preterm", "continuous positive airway pressure", "preterm", and "bronchopulmonary dysplasia". The resulting data and other relevant information were divided into several topics to ensure a thorough, critical view of ventilation-induced lung injury and its consequences in preterm infants. The role of pro-inflammatory cytokines (particularly interleukins 6 and 8 and tumor necrosis factor alpha) as mediators of lung injury was assessed. Evidence from studies conducted with animals and human newborns is described. This evidence shows that brief periods of mechanical ventilation is sufficient to induce the release of pro-inflammatory cytokines. Other forms of mechanical and non-invasive ventilation were also analyzed as protective alternatives to conventional mechanical ventilation. It was concluded that non-invasive ventilation, intubation followed by early surfactant administration and quick extubation for nasal continuous positive airway pressure, and strategies that regulate tidal volume and avoid volutrauma (such as volume guarantee ventilation) protect against ventilator-induced lung injury in preterm infants. PMID:24553514

  20. Distribution of lung blood on modified bilateral Glenn shunt evaluated by Tc-99m-MAA lung perfusion scintigraphy

    PubMed Central

    Si, Biao; Luan, Zhao-sheng; Wang, Tong-jian; Ning, Yan-song; Li, Na; Zhu, Meng; Liu, Zhong-min; Ding, Guang-hong; Qiao, Bin

    2016-01-01

    Abstract The aim of the present study was to determine the distribution of lung blood in a modified bilateral Glenn procedure designed in our institute with lung perfusion scintigraphy. Sixteen consecutive patients who underwent modified bilateral Glenn operation from 2011 to 2014 were enrolled in the study. The control group consisted of 7 patients who underwent bidirectional Glenn shunt. Radionuclide lung perfusion scintigraphy was performed using Tc-99m-macro aggregated albumin (MAA) in all patients. For the patients in modified bilateral Glenn group, the time at which the radioactivity accumulation peaked did not differ significantly between the right and left lung field (t = 0.608, P = 0.554). The incidence of perfusion abnormality in each lung lobe also did not differ significantly (P = 0.426 by Fisher exact test). The radioactive counts were higher in the right lung than in the left lung, but the difference was not statistically significant (t = 1.502, P = 0.157). Radioactive perfusion in the lower lung field was significantly greater than that in the upper field (t = 4.368, P < 0.001). Compared with that in the bidirectional Glenn group, the ratio of radioactivity in the right lung to that in left lung was significantly lower in the modified bilateral Glenn group (t = 3.686, P = 0.002). Lung perfusion scintigraphy confirmed the benefit of the modified bilateral Glenn shunt with regard to more balanced blood perfusion in both lungs. PMID:27661042

  1. /sup 57/Co-bleomycin scintigraphy for the staging of lung cancer

    SciTech Connect

    Nieweg, O.E.; Piers, D.A.; Beekhuis, H.; Sluiter, H.J.; van der Wal, A.M.; Woldring, M.G.

    1989-03-15

    The value of Cobalt-57 bleomycin (/sup 57/Co-BLM) scintigraphy in the detection of lymph node metastases in the hilum and mediastinum was investigated in 132 patients with peripherally located lung cancer. In one half of the patients with metastases, these were visualized. Specificity was 98%. These results were better than those obtained with chest radiography and conventional roentgen tomography. /sup 57/Co-BLM scintigraphy is routinely used in the staging of patients with lung cancer, obviating the need for mediastinoscopy.

  2. Critical evaluation of lung scintigraphy in cystic fibrosis: study of 113 patients

    SciTech Connect

    Piepsz, A.; Wetzburger, C.; Spehl, M.; Machin, D.; Dab, I.; Ham, H.R.; Vandevivere, J.; Baran, D.

    1980-10-01

    A long-term study has been performed on 285 lung perfusion scintigrams obtained from 113 patients with cystic fibrosis. Transverse and longitudinal comparisons with clinical and radiological scores, as well as retrospective analysis of the deceased patients, were the methods used in order to evaluate the importance of the scintigraphic images. It appears that lung scintigraphy is the best index of the regional lung impairment, and contributes, as does a chest radiograph, to the early detection of lung lesions, the two methods being complementary.

  3. Diagnosis of pulmonary embolism: ventilation perfusion scintigraphy versus helical computed tomography pulmonary angiography.

    PubMed

    Macdonald, W B G; Patrikeos, A P; Thompson, R I; Adler, B D; van der Schaaf, A A

    2005-02-01

    The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses.

  4. Dependent Lung Tension Pneumothorax During 1-Lung Ventilation: Treatment by Transmediastinal Thoracentesis.

    PubMed

    Kenta, Okitsu; Shoko, Arimoto; Takeshi, Iritakenishi; Satoshi, Hagihira; Yuji, Fujino; Yasushi, Shintani; Masato, Minami; Meinoshin, Okumura

    2015-08-15

    Contralateral tension pneumothorax during 1-lung ventilation is rare but life threatening. We report the case of a patient who developed tension pneumothorax of the dependent lung during 1-lung ventilation while the surgeon was anastomosing the bronchi after sleeve lobectomy. Ventilation was not possible in either the dependent or nondependent lung, leading to severe desaturation and cardiac arrest. While the surgeons were administering direct cardiac compression, we suspected tension pneumothorax. As soon as the surgeons pierced the mediastinal pleura, adequate circulation was restored. Immediate diagnosis and treatment is important for this complication.

  5. Dependent Lung Tension Pneumothorax During 1-Lung Ventilation: Treatment by Transmediastinal Thoracentesis.

    PubMed

    Kenta, Okitsu; Shoko, Arimoto; Takeshi, Iritakenishi; Satoshi, Hagihira; Yuji, Fujino; Yasushi, Shintani; Masato, Minami; Meinoshin, Okumura

    2015-08-15

    Contralateral tension pneumothorax during 1-lung ventilation is rare but life threatening. We report the case of a patient who developed tension pneumothorax of the dependent lung during 1-lung ventilation while the surgeon was anastomosing the bronchi after sleeve lobectomy. Ventilation was not possible in either the dependent or nondependent lung, leading to severe desaturation and cardiac arrest. While the surgeons were administering direct cardiac compression, we suspected tension pneumothorax. As soon as the surgeons pierced the mediastinal pleura, adequate circulation was restored. Immediate diagnosis and treatment is important for this complication. PMID:26275308

  6. Activation of calpains mediates early lung neutrophilic inflammation in ventilator-induced lung injury

    PubMed Central

    Liu, Dejie; Yan, Zhibo; Minshall, Richard D.; Schwartz, David E.; Chen, Yuguo

    2012-01-01

    Lung inflammatory responses in the absence of infection are considered to be one of primary mechanisms of ventilator-induced lung injury. Here, we determined the role of calpain in the pathogenesis of lung inflammation attributable to mechanical ventilation. Male C57BL/6J mice were subjected to high (28 ml/kg) tidal volume ventilation for 2 h in the absence and presence of calpain inhibitor I (10 mg/kg). To address the isoform-specific functions of calpain 1 and calpain 2 during mechanical ventilation, we utilized a liposome-based delivery system to introduce small interfering RNAs targeting each isoform in pulmonary vasculature in vivo. Mechanical ventilation with high tidal volume induced rapid (within minutes) and persistent calpain activation and lung inflammation as evidenced by neutrophil recruitment, production of TNF-α and IL-6, pulmonary vascular hyperpermeability, and lung edema formation. Pharmaceutical calpain inhibition significantly attenuated these inflammatory responses caused by lung hyperinflation. Depletion of calpain 1 or calpain 2 had a protective effect against ventilator-induced lung inflammatory responses. Inhibition of calpain activity by means of siRNA silencing or pharmacological inhibition also reduced endothelial nitric oxide (NO) synthase (NOS-3)-mediated NO production and subsequent ICAM-1 phosphorylation following high tidal volume ventilation. These results suggest that calpain activation mediates early lung inflammation during ventilator-induced lung injury via NOS-3/NO-dependent ICAM-1 phosphorylation and neutrophil recruitment. Inhibition of calpain activation may therefore provide a novel and promising strategy for the prevention and treatment of ventilator-induced lung injury. PMID:22140070

  7. Exposure to mechanical ventilation promotes tolerance to ventilator-induced lung injury by Ccl3 downregulation.

    PubMed

    Blázquez-Prieto, Jorge; López-Alonso, Inés; Amado-Rodríguez, Laura; Batalla-Solís, Estefanía; González-López, Adrián; Albaiceta, Guillermo M

    2015-10-15

    Inflammation plays a key role in the development of ventilator-induced lung injury (VILI). Preconditioning with a previous exposure can damp the subsequent inflammatory response. Our objectives were to demonstrate that tolerance to VILI can be induced by previous low-pressure ventilation, and to identify the molecular mechanisms responsible for this phenomenon. Intact 8- to 12-wk-old male CD1 mice were preconditioned with 90 min of noninjurious ventilation [peak pressure 17 cmH2O, positive end-expiratory pressure (PEEP) 2 cmH2O] and extubated. Seven days later, preconditioned mice and intact controls were submitted to injurious ventilation (peak pressure 20 cmH2O, PEEP 0 cmH2O) for 2 h to induce VILI. Preconditioned mice showed lower histological lung injury scores, bronchoalveolar lavage albumin content, and lung neutrophilic infiltration after injurious ventilation, with no differences in Il6 or Il10 expression. Microarray analyses revealed a downregulation of Calcb, Hspa1b, and Ccl3, three genes related to tolerance phenomena, in preconditioned animals. Among the previously identified genes, only Ccl3, which encodes the macrophage inflammatory protein 1 alpha (MIP-1α), showed significant differences between intact and preconditioned mice after high-pressure ventilation. In separate, nonconditioned animals, treatment with BX471, a specific blocker of CCR1 (the main receptor for MIP-1α), decreased lung damage and neutrophilic infiltration caused by high-pressure ventilation. We conclude that previous exposure to noninjurious ventilation induces a state of tolerance to VILI. Downregulation of the chemokine gene Ccl3 could be the mechanism responsible for this effect.

  8. Heliox Improves Carbon Dioxide Removal during Lung Protective Mechanical Ventilation.

    PubMed

    Beurskens, Charlotte J; Brevoord, Daniel; Lagrand, Wim K; van den Bergh, Walter M; Vroom, Margreeth B; Preckel, Benedikt; Horn, Janneke; Juffermans, Nicole P

    2014-01-01

    Introduction. Helium is a noble gas with low density and increased carbon dioxide (CO2) diffusion capacity. This allows lower driving pressures in mechanical ventilation and increased CO2 diffusion. We hypothesized that heliox facilitates ventilation in patients during lung-protective mechanical ventilation using low tidal volumes. Methods. This is an observational cohort substudy of a single arm intervention study. Twenty-four ICU patients were included, who were admitted after a cardiac arrest and mechanically ventilated for 3 hours with heliox (50% helium; 50% oxygen). A fixed protective ventilation protocol (6 mL/kg) was used, with prospective observation for changes in lung mechanics and gas exchange. Statistics was by Bonferroni post-hoc correction with statistical significance set at P < 0.017. Results. During heliox ventilation, respiratory rate decreased (25 ± 4 versus 23 ± 5 breaths min(-1), P = 0.010). Minute volume ventilation showed a trend to decrease compared to baseline (11.1 ± 1.9 versus 9.9 ± 2.1 L min(-1), P = 0.026), while reducing PaCO2 levels (5.0 ± 0.6 versus 4.5 ± 0.6 kPa, P = 0.011) and peak pressures (21.1 ± 3.3 versus 19.8 ± 3.2 cm H2O, P = 0.024). Conclusions. Heliox improved CO2 elimination while allowing reduced minute volume ventilation in adult patients during protective mechanical ventilation.

  9. Preemptive mechanical ventilation can block progressive acute lung injury

    PubMed Central

    Sadowitz, Benjamin; Jain, Sumeet; Kollisch-Singule, Michaela; Satalin, Joshua; Andrews, Penny; Habashi, Nader; Gatto, Louis A; Nieman, Gary

    2016-01-01

    Mortality from acute respiratory distress syndrome (ARDS) remains unacceptable, approaching 45% in certain high-risk patient populations. Treating fulminant ARDS is currently relegated to supportive care measures only. Thus, the best treatment for ARDS may lie with preventing this syndrome from ever occurring. Clinical studies were examined to determine why ARDS has remained resistant to treatment over the past several decades. In addition, both basic science and clinical studies were examined to determine the impact that early, protective mechanical ventilation may have on preventing the development of ARDS in at-risk patients. Fulminant ARDS is highly resistant to both pharmacologic treatment and methods of mechanical ventilation. However, ARDS is a progressive disease with an early treatment window that can be exploited. In particular, protective mechanical ventilation initiated before the onset of lung injury can prevent the progression to ARDS. Airway pressure release ventilation (APRV) is a novel mechanical ventilation strategy for delivering a protective breath that has been shown to block progressive acute lung injury (ALI) and prevent ALI from progressing to ARDS. ARDS mortality currently remains as high as 45% in some studies. As ARDS is a progressive disease, the key to treatment lies with preventing the disease from ever occurring while it remains subclinical. Early protective mechanical ventilation with APRV appears to offer substantial benefit in this regard and may be the prophylactic treatment of choice for preventing ARDS. PMID:26855896

  10. Preemptive mechanical ventilation can block progressive acute lung injury.

    PubMed

    Sadowitz, Benjamin; Jain, Sumeet; Kollisch-Singule, Michaela; Satalin, Joshua; Andrews, Penny; Habashi, Nader; Gatto, Louis A; Nieman, Gary

    2016-02-01

    Mortality from acute respiratory distress syndrome (ARDS) remains unacceptable, approaching 45% in certain high-risk patient populations. Treating fulminant ARDS is currently relegated to supportive care measures only. Thus, the best treatment for ARDS may lie with preventing this syndrome from ever occurring. Clinical studies were examined to determine why ARDS has remained resistant to treatment over the past several decades. In addition, both basic science and clinical studies were examined to determine the impact that early, protective mechanical ventilation may have on preventing the development of ARDS in at-risk patients. Fulminant ARDS is highly resistant to both pharmacologic treatment and methods of mechanical ventilation. However, ARDS is a progressive disease with an early treatment window that can be exploited. In particular, protective mechanical ventilation initiated before the onset of lung injury can prevent the progression to ARDS. Airway pressure release ventilation (APRV) is a novel mechanical ventilation strategy for delivering a protective breath that has been shown to block progressive acute lung injury (ALI) and prevent ALI from progressing to ARDS. ARDS mortality currently remains as high as 45% in some studies. As ARDS is a progressive disease, the key to treatment lies with preventing the disease from ever occurring while it remains subclinical. Early protective mechanical ventilation with APRV appears to offer substantial benefit in this regard and may be the prophylactic treatment of choice for preventing ARDS. PMID:26855896

  11. Recurrent Recruitment Manoeuvres Improve Lung Mechanics and Minimize Lung Injury during Mechanical Ventilation of Healthy Mice

    PubMed Central

    Reiss, Lucy Kathleen; Kowallik, Anke; Uhlig, Stefan

    2011-01-01

    Introduction Mechanical ventilation (MV) of mice is increasingly required in experimental studies, but the conditions that allow stable ventilation of mice over several hours have not yet been fully defined. In addition, most previous studies documented vital parameters and lung mechanics only incompletely. The aim of the present study was to establish experimental conditions that keep these parameters within their physiological range over a period of 6 h. For this purpose, we also examined the effects of frequent short recruitment manoeuvres (RM) in healthy mice. Methods Mice were ventilated at low tidal volume VT = 8 mL/kg or high tidal volume VT = 16 mL/kg and a positive end-expiratory pressure (PEEP) of 2 or 6 cmH2O. RM were performed every 5 min, 60 min or not at all. Lung mechanics were followed by the forced oscillation technique. Blood pressure (BP), electrocardiogram (ECG), heart frequency (HF), oxygen saturation and body temperature were monitored. Blood gases, neutrophil-recruitment, microvascular permeability and pro-inflammatory cytokines in bronchoalveolar lavage (BAL) and blood serum as well as histopathology of the lung were examined. Results MV with repetitive RM every 5 min resulted in stable respiratory mechanics. Ventilation without RM worsened lung mechanics due to alveolar collapse, leading to impaired gas exchange. HF and BP were affected by anaesthesia, but not by ventilation. Microvascular permeability was highest in atelectatic lungs, whereas neutrophil-recruitment and structural changes were strongest in lungs ventilated with high tidal volume. The cytokines IL-6 and KC, but neither TNF nor IP-10, were elevated in the BAL and serum of all ventilated mice and were reduced by recurrent RM. Lung mechanics, oxygenation and pulmonary inflammation were improved by increased PEEP. Conclusions Recurrent RM maintain lung mechanics in their physiological range during low tidal volume ventilation of healthy mice by preventing atelectasis and

  12. Subsequent investigation and management of patients with intermediate-category and -probability ventilation-perfusion scintigraphy.

    PubMed

    Walsh, G; Jones, D N

    2000-11-01

    The authors wished to determine the proportion of patients with intermediate-category and intermediate-probability ventilation-perfusion scintigraphy (IVQS) who proceed to further imaging for investigation of thromboembolism, to identify the defining clinical parameters and to determine the proportion of patients who have a definite imaging diagnosis of thromboembolism prior to discharge from hospital on anticoagulation therapy. One hundred and twelve VQS studies performed at the Flinders Medical Centre over a 9-month period were reported as having intermediate category and probability for pulmonary embolism. Medical case notes were available for review in 99 of these patients and from these the pretest clinical probability, subsequent patient progress and treatment were recorded. Eight cases were excluded because they were already receiving anticoagulation therapy. In the remaining 91 patients the pretest clinical probability was considered to be low in 25; intermediate in 30; and high in 36 cases. In total, 51.6% (n = 47) of these patients (8% (n = 2) with low, 66% (n = 20) with intermediate, and 69.4% (n = 25) with high pretest probability) proceeded to CT pulmonary angiography (CTPA) and/or lower limb duplex Doppler ultrasound (DUS) evaluation. Of the patients with IVQS results, 30.7% (n = 28) were evaluated with CTPA. No patient with a low, all patients with a high and 46% of patients with an intermediate pretest probability initially received anticoagulation therapy. This was discontinued in three patients with high and in 12 patients with intermediate clinical probability prior to discharge from hospital. Overall, 40% of patients discharged on anticoagulation therapy (including 39% of those with a high pretest probability) had a positive imaging diagnosis of thromboembolism The results suggest that, although the majority of patients with intermediate-to-high pretest probability and IVQS proceed to further imaging investigation, CTPA is relatively underused

  13. [Lung-brain interaction in the mechanically ventilated patient].

    PubMed

    López-Aguilar, J; Fernández-Gonzalo, M S; Turon, M; Quílez, M E; Gómez-Simón, V; Jódar, M M; Blanch, L

    2013-10-01

    Patients with acute lung injury or acute respiratory distress syndrome (ARDS) admitted to the ICU present neuropsychological alterations, which in most cases extend beyond the acute phase and have an important adverse effect upon quality of life. The aim of this review is to deepen in the analysis of the complex interaction between lung and brain in critically ill patients subjected to mechanical ventilation. This update first describes the neuropsychological alterations occurring both during the acute phase of ICU stay and at discharge, followed by an analysis of lung-brain interactions during mechanical ventilation, and finally explores the etiology and mechanisms leading to the neurological disorders observed in these patients. The management of critical patients requires an integral approach focused on minimizing the deleterious effects over the short, middle or long term.

  14. [Lung-brain interaction in the mechanically ventilated patient].

    PubMed

    López-Aguilar, J; Fernández-Gonzalo, M S; Turon, M; Quílez, M E; Gómez-Simón, V; Jódar, M M; Blanch, L

    2013-10-01

    Patients with acute lung injury or acute respiratory distress syndrome (ARDS) admitted to the ICU present neuropsychological alterations, which in most cases extend beyond the acute phase and have an important adverse effect upon quality of life. The aim of this review is to deepen in the analysis of the complex interaction between lung and brain in critically ill patients subjected to mechanical ventilation. This update first describes the neuropsychological alterations occurring both during the acute phase of ICU stay and at discharge, followed by an analysis of lung-brain interactions during mechanical ventilation, and finally explores the etiology and mechanisms leading to the neurological disorders observed in these patients. The management of critical patients requires an integral approach focused on minimizing the deleterious effects over the short, middle or long term. PMID:23260265

  15. Analysis of lung ventilation in the aestivating lungfish Protopterus aethiopicus.

    PubMed

    DeLaney, R G; Fishman, A P

    1977-11-01

    During aestivation, the breathing pattern of the lungfish changed from the usual aquatic pattern of a single breath followed by prolonged apnea to the pattern of alternating tachypnea and apnea that characterizes Cheyne-Stokes breathing. As aestivation continued, the number of breaths per tachypneic period increased gradually to reach a steady level at about the 3rd mo. During the bouts of tachypnea, minute ventilation increased because of the increase in respiratory frequency even though tidal volumes decreased. Ventilation of the lungs during aestivation appeared to involve the same mechanism as during life in water, i.e., a buccal force pump. The breathing cycle began with the aspiration of air into the mouth as the buccal cavity enlarged. Lung deflation then occurred abetted by contraction of the abdominal muscles. Lung inflation followed and involved the "swallowing" of air form the posterior buccal region into the lungs. Cycles of deflation and partial inflation of the lungs were repeated 8-40 times (tachypneic period). At the end of the tachypneic cycle, after the last deflation, a series of larger buccal force-pump maneuvers reinflated the lungs before the start of the apneic period. PMID:920828

  16. Distribution of lung blood on modified bilateral Glenn shunt evaluated by Tc-99m-MAA lung perfusion scintigraphy: A retrospective study.

    PubMed

    Si, Biao; Luan, Zhao-Sheng; Wang, Tong-Jian; Ning, Yan-Song; Li, Na; Zhu, Meng; Liu, Zhong-Min; Ding, Guang-Hong; Qiao, Bin

    2016-09-01

    The aim of the present study was to determine the distribution of lung blood in a modified bilateral Glenn procedure designed in our institute with lung perfusion scintigraphy. Sixteen consecutive patients who underwent modified bilateral Glenn operation from 2011 to 2014 were enrolled in the study. The control group consisted of 7 patients who underwent bidirectional Glenn shunt. Radionuclide lung perfusion scintigraphy was performed using Tc-99m-macro aggregated albumin (MAA) in all patients. For the patients in modified bilateral Glenn group, the time at which the radioactivity accumulation peaked did not differ significantly between the right and left lung field (t = 0.608, P = 0.554). The incidence of perfusion abnormality in each lung lobe also did not differ significantly (P = 0.426 by Fisher exact test). The radioactive counts were higher in the right lung than in the left lung, but the difference was not statistically significant (t = 1.502, P = 0.157). Radioactive perfusion in the lower lung field was significantly greater than that in the upper field (t = 4.368, P < 0.001). Compared with that in the bidirectional Glenn group, the ratio of radioactivity in the right lung to that in left lung was significantly lower in the modified bilateral Glenn group (t = 3.686, P = 0.002). Lung perfusion scintigraphy confirmed the benefit of the modified bilateral Glenn shunt with regard to more balanced blood perfusion in both lungs. PMID:27661042

  17. Distribution of lung blood on modified bilateral Glenn shunt evaluated by Tc-99m-MAA lung perfusion scintigraphy: A retrospective study.

    PubMed

    Si, Biao; Luan, Zhao-Sheng; Wang, Tong-Jian; Ning, Yan-Song; Li, Na; Zhu, Meng; Liu, Zhong-Min; Ding, Guang-Hong; Qiao, Bin

    2016-09-01

    The aim of the present study was to determine the distribution of lung blood in a modified bilateral Glenn procedure designed in our institute with lung perfusion scintigraphy. Sixteen consecutive patients who underwent modified bilateral Glenn operation from 2011 to 2014 were enrolled in the study. The control group consisted of 7 patients who underwent bidirectional Glenn shunt. Radionuclide lung perfusion scintigraphy was performed using Tc-99m-macro aggregated albumin (MAA) in all patients. For the patients in modified bilateral Glenn group, the time at which the radioactivity accumulation peaked did not differ significantly between the right and left lung field (t = 0.608, P = 0.554). The incidence of perfusion abnormality in each lung lobe also did not differ significantly (P = 0.426 by Fisher exact test). The radioactive counts were higher in the right lung than in the left lung, but the difference was not statistically significant (t = 1.502, P = 0.157). Radioactive perfusion in the lower lung field was significantly greater than that in the upper field (t = 4.368, P < 0.001). Compared with that in the bidirectional Glenn group, the ratio of radioactivity in the right lung to that in left lung was significantly lower in the modified bilateral Glenn group (t = 3.686, P = 0.002). Lung perfusion scintigraphy confirmed the benefit of the modified bilateral Glenn shunt with regard to more balanced blood perfusion in both lungs.

  18. SU-E-J-249: Correlation of Mean Lung Ventilation Value with Ratio of Total Lung Volumes

    SciTech Connect

    Yu, N; Qu, H; Xia, P

    2014-06-01

    Purpose: Lung ventilation function measured from 4D-CT and from breathing correlated CT images is a novel concept to incorporate the lung physiologic function into treatment planning of radiotherapy. The calculated ventilation functions may vary from different breathing patterns, affecting evaluation of the treatment plans. The purpose of this study is to correlate the mean lung ventilation value with the ratio of the total lung volumes obtained from the relevant CTs. Methods: A ventilation map was calculated from the variations of voxel-to-voxel CT densities from two breathing phases from either 4D-CT or breathing correlated CTs. An open source image registration tool of Plastimatch was used to deform the inhale phase images to the exhale phase images. To calculate the ventilation map inside lung, the whole lung was delineated and the tissue outside the lung was masked out. With a software tool developed in house, the 3D ventilation map was then converted in the DICOM format associated with the planning CT images. The ventilation map was analyzed on a clinical workstation. To correlate ventilation map thus calculated with lung volume change, the total lung volume change was compared the mean ventilation from our method. Results: Twenty two patients who underwent stereotactic body irradiation for lung cancer was selected for this retrospective study. For this group of patients, the ratio of lung volumes for the inhale (Vin ) and exhale phase (Vex ) was shown to be linearly related to the mean of the local ventilation (Vent), Vin/Vex=1.+0.49*Vent (R2=0.93, p<0.01). Conclusion: The total lung volume change is highly correlated with the mean of local ventilation. The mean of local ventilation may be useful to assess the patient's lung capacity.

  19. Protective Ventilation of Preterm Lambs Exposed to Acute Chorioamnionitis Does Not Reduce Ventilation-Induced Lung or Brain Injury

    PubMed Central

    Barton, Samantha K.; Moss, Timothy J. M.; Hooper, Stuart B.; Crossley, Kelly J.; Gill, Andrew W.; Kluckow, Martin; Zahra, Valerie; Wong, Flora Y.; Pichler, Gerhard; Galinsky, Robert; Miller, Suzanne L.

    2014-01-01

    Background The onset of mechanical ventilation is a critical time for the initiation of cerebral white matter (WM) injury in preterm neonates, particularly if they are inadvertently exposed to high tidal volumes (VT) in the delivery room. Protective ventilation strategies at birth reduce ventilation-induced lung and brain inflammation and injury, however its efficacy in a compromised newborn is not known. Chorioamnionitis is a common antecedent of preterm birth, and increases the risk and severity of WM injury. We investigated the effects of high VT ventilation, after chorioamnionitis, on preterm lung and WM inflammation and injury, and whether a protective ventilation strategy could mitigate the response. Methods Pregnant ewes (n = 18) received intra-amniotic lipopolysaccharide (LPS) 2 days before delivery, instrumentation and ventilation at 127±1 days gestation. Lambs were either immediately euthanased and used as unventilated controls (LPSUVC; n = 6), or were ventilated using an injurious high VT strategy (LPSINJ; n = 5) or a protective ventilation strategy (LPSPROT; n = 7) for a total of 90 min. Mean arterial pressure, heart rate and cerebral haemodynamics and oxygenation were measured continuously. Lungs and brains underwent molecular and histological assessment of inflammation and injury. Results LPSINJ lambs had poorer oxygenation than LPSPROT lambs. Ventilation requirements and cardiopulmonary and systemic haemodynamics were not different between ventilation strategies. Compared to unventilated lambs, LPSINJ and LPSPROT lambs had increases in pro-inflammatory cytokine expression within the lungs and brain, and increased astrogliosis (p<0.02) and cell death (p<0.05) in the WM, which were equivalent in magnitude between groups. Conclusions Ventilation after acute chorioamnionitis, irrespective of strategy used, increases haemodynamic instability and lung and cerebral inflammation and injury. Mechanical ventilation is a potential contributor

  20. The physical basis of ventilator-induced lung injury

    PubMed Central

    Plataki, Maria; Hubmayr, Rolf D

    2010-01-01

    Although mechanical ventilation (MV) is a life-saving intervention for patients with acute respiratory distress syndrome (ARDS), it can aggravate or cause lung injury, known as ventilator-induced lung injury (VILI). The biophysical characteristics of heterogeneously injured ARDS lungs increase the parenchymal stress associated with breathing, which is further aggravated by MV. Cells, in particular those lining the capillaries, airways and alveoli, transform this strain into chemical signals (mechanotransduction). The interaction of reparative and injurious mechanotransductive pathways leads to VILI. Several attempts have been made to identify clinical surrogate measures of lung stress/strain (e.g., density changes in chest computed tomography, lower and upper inflection points of the pressure–volume curve, plateau pressure and inflammatory cytokine levels) that could be used to titrate MV. However, uncertainty about the topographical distribution of stress relative to that of the susceptibility of the cells and tissues to injury makes the existence of a single ‘global’ stress/strain injury threshold doubtful. PMID:20524920

  1. Nicotinamide Exacerbates Hypoxemia in Ventilator-Induced Lung Injury Independent of Neutrophil Infiltration

    PubMed Central

    Jones, Heather D.; Yoo, Jeena; Crother, Timothy R.; Kyme, Pierre; Ben-Shlomo, Anat; Khalafi, Ramtin; Tseng, Ching W.; Parks, William C.; Arditi, Moshe

    2015-01-01

    Background Ventilator-induced lung injury is a form of acute lung injury that develops in critically ill patients on mechanical ventilation and has a high degree of mortality. Nicotinamide phosphoribosyltransferase is an enzyme that is highly upregulated in ventilator-induced lung injury and exacerbates the injury when given exogenously. Nicotinamide (vitamin B3) directly inhibits downstream pathways activated by Nicotinamide phosphoribosyltransferase and is protective in other models of acute lung injury. Methods We administered nicotinamide i.p. to mice undergoing mechanical ventilation with high tidal volumes to study the effects of nicotinamide on ventilator-induced lung injury. Measures of injury included oxygen saturations and bronchoalveolar lavage neutrophil counts, protein, and cytokine levels. We also measured expression of nicotinamide phosophoribosyltransferase, and its downstream effectors Sirt1 and Cebpa, Cebpb, Cebpe. We assessed the effect of nicotinamide on the production of nitric oxide during ventilator-induced lung injury. We also studied the effects of ventilator-induced lung injury in mice deficient in C/EBPε. Results Nicotinamide treatment significantly inhibited neutrophil infiltration into the lungs during ventilator-induced lung injury, but did not affect protein leakage or cytokine production. Surprisingly, mice treated with nicotinamide developed significantly worse hypoxemia during mechanical ventilation. This effect was not linked to increases in nitric oxide production or alterations in expression of Nicotinamide phosphoribosyl transferase, Sirt1, or Cebpa and Cebpb. Cebpe mRNA levels were decreased with either nicotinamide treatment or mechanical ventilation, but mice lacking C/EBPε developed the same degree of hypoxemia and ventilator-induced lung injury as wild-type mice. Conclusions Nicotinamide treatment during VILI inhibits neutrophil infiltration of the lungs consistent with a strong anti-inflammatory effect, but

  2. Lung ventilation contributes to vertical lymph movement in anurans.

    PubMed

    Hedrick, Michael S; Drewes, Robert C; Hillman, Stanley S; Withers, Philip C

    2007-11-01

    Anurans (frogs and toads) generate lymphatic fluid at 10 times the rate in mammals, largely as a consequence of their very 'leaky' vasculature and high interstitial compliance. Lymph is ultimately pumped into the venous system by paired, dorsally located lymph hearts. At present, it is unclear how lymphatic fluid that accumulates in central body subcutaneous lymph sacs is moved to the anterior and posterior lymph hearts in the axillary regions and how lymph is moved, against gravity, to the dorsally located lymph hearts. In this study, we tested the hypothesis that lung ventilation, through its consequent effects on lymph sac pressure, contributes to the vertical movement of lymphatic fluid in the cane toad (Chaunus marinus) and the North American bullfrog (Lithobates catesbeiana). We measured pressure in the dorsal, lateral and subvertebral lymph sacs of anesthetized cane toads and bullfrogs during artificial lung inflation and deflation. We also measured pressure in the subvertebral lymph sac, which adheres to the dorsal surface of the lungs, simultaneously with brachial (forelimb) and pubic (posterior) sac pressure during ventilation in freely behaving animals. There were highly significant (P<0.001) relationships between lung pressure and lymph sac pressures (r(2)=0.19-0.72), indicating that pulmonary pressure is transmitted to the highly compliant lymph sacs that surround the lungs. Subvertebral sac pressure of resting animals was not significantly different between L. catesbeiana (518+/-282 Pa) and C. marinus (459+/-111 Pa). Brachial sac compliance (ml kPa(-1) kg(-1)) also did not differ between the two species (33.6+/-5.0 in L. catesbeiana and 37.0+/-9.4 in C. marinus). During expiration (lung deflation), reductions in expanding subvertebral sac pressure are communicated to the brachial lymph sac. Changes in brachial and pubic lymph sac pressures were correlated almost entirely during expiration rather than inspiration. The change in brachial sac pressure

  3. Abolished ventilation and perfusion of lung caused by blood clot in the left main bronchus: auto-downregulation of pulmonary arterial blood supply.

    PubMed

    Afzelius, P; Bergmann, A; Henriksen, J H

    2015-01-01

    It is generally assumed that the lungs possess arterial autoregulation associated with bronchial obstruction. A patient with pneumonia and congestive heart failure unexpectedly developed frequent haemoptysis. High-resolution CT and diagnostic CT were performed as well as ventilation/perfusion (V/Q) scintigraphy with single-photon emission CT (SPECT)/CT. V/Q SPECT/CT demonstrated abolished ventilation due to obstruction of the left main bronchus and markedly reduced perfusion of the entire left lung, a condition that was completely reversed after removal of a blood clot. We present the first pictorially documented case of hypoxia-induced pulmonary vasoconstriction and flow shift in a main pulmonary artery due to a complete intrinsic obstruction of the ipsilateral main bronchus. The condition is reversible, contingent on being relieved within a few days. PMID:26374773

  4. Evaluation of primary lung cancer with indium 111 anti-carcinoembryonic antigen (type ZCE-025) monoclonal antibody scintigraphy

    SciTech Connect

    Krishnamurthy, S.; Morris, J.F.; Antonovic, R.; Ahmed, A.; Galey, W.T.; Duncan, C.; Krishnamurthy, G.T. )

    1990-02-01

    A study was undertaken to test whether indium 111 (111In)-labeled anti-carcinoembryonic antigen (CEA) (type ZCE 025) monoclonal intact antibody (MoAb) would concentrate in primary lung cancer enabling its detection and localization by scintigraphy. The scintigraphic results were correlated with chest radiograph, computed tomograph (CT), bronchoscopy, surgical resection, and tumor CEA analysis. Twenty adult male patients with clinical suspicion of primary lung cancer were studied. Each subject was infused with 4 to 5 mCi of 111In anti-CEA ZCE 025 MoAb, and planar and tomographic scintiphotos were obtained on days 3 and 6 or 7 postinfusion. The scintigraphy was true-positive in 12 of 16 patients with primary lung cancer, eight of nine patients with squamous cell carcinoma, and four of seven with adenocarcinoma; it was true-negative in three of four patients with benign lung disease with an overall accuracy of 75%. In seven patients with confirmed primary lung cancer, but with negative bronchoscopic findings, the scintigraphy was true-positive in four. In 11 patients with definitely positive or suspicious malignancy by bronchoscopy the monoclonal scintigraphy was positive in eight. In true-positive cases, the location and size of the lesion by 111In anti-CEA ZCE 025 MoAb imaging correlated well with CT findings and also tumor mass at surgery. Only one of 12 tumors stained positive for CEA had serum CEA levels greater than 10 ng/ml, indicating nonleakage of the tumor antigen into general circulation in early lung cancer. It is concluded that 111In anti-CEA ZCE 025 MoAb planar and tomographic imaging shows potential to serve as a noninvasive diagnostic test in the evaluation of primary lung cancer. The lung lesion is likely to be malignant if it concentrates 111In anti-CEA ZCE 025 MoAb and benign if it does not.

  5. Prediction of postoperative loss of lung function in patients with malignant lung mass. Quantitative regional ventilation-perfusion scanning

    SciTech Connect

    Ryo, U.Y. )

    1990-05-01

    The quantitative measurement of regional ventilation and perfusion distribution is simply and reliably accomplished by using routinely available radioactive gas and perfusion lung scanning agents, and a large field-of-view gamma camera with an on-line computer. The preoperative prediction of postsurgical loss in lung function can be made accurately by using the quantitative ventilation-perfusion lung scan technique. Either a regional ventilation study or perfusion study may be used for the prediction, but analysis of regional ventilation distribution appears to be a better parameter than that of perfusion distribution for the prediction of postoperative loss of FEV1. In the rare case of a patient with a marked ventilation-perfusion deficit, quantitative distribution of both ventilation and perfusion may be needed for an accurate assessment of postsurgical lung function. 18 references.

  6. 81mKr gas generator for lung ventilation study.

    PubMed

    Koyama, T; Koyama, T; Hirokawa, Y; Yoshizawa, Y; Noma, H; Horiguchi, T; Kiso, Y; Hasai, H; Takemi, H

    1980-12-01

    A generator of 81mKr was designed and tested. The parent nuclide 81Rb was produced by the 70 MeV proton induced reactions on a Rb2SO4 target. 81mKr was bubbled out with oxygen gas from the 81Rb solution, and collected in a reservoir for lung ventilation studies. The generator was continuously operated at the high flow rate up to 10 1/min. The generator efficiency was 86%. The collection rates in the reservoir were examined under several flow rates. The pure 81mKr isomer was observed wih a NaI (T1) detector at the reservoir.

  7. Exhaled volatile organic compounds as lung cancer biomarkers during one-lung ventilation.

    PubMed

    Wang, Changsong; Dong, Ran; Wang, Xiaoyang; Lian, Ailing; Chi, Chunjie; Ke, Chaofu; Guo, Lei; Liu, Shanshan; Zhao, Wei; Xu, Guowang; Li, Enyou

    2014-01-01

    In this study, single-lung ventilation was used to detect differences in the volatile organic compound (VOCs) profiles between lung tissues in healthy and affected lungs. In addition, changes that occurred after lung cancer resection in both the VOCs profiles of exhaled breath from ipsilateral and contralateral lungs and the VOCs profiles of exhaled breath and blood sample headspaces were also determined. Eighteen patients with non-small cell carcinoma were enrolled. Alveolar breath samples were taken separately from healthy and diseased lungs before and after the tumor resection. Solid phase microextraction-gas chromatography/mass spectrometry was used to assess the exhaled VOCs of the study participants. The VOCs exhibited significant differences between the contralateral and ipsilateral lungs before surgery, the contralateral and ipsilateral lungs after surgery, the ipsilateral lungs before and after surgery, and the blood samples from before and after surgery; 12, 19, 12 and 5 characteristic metabolites played decisive roles in sample classification, respectively. 2,2-Dimethyldecane, tetradecane, 2,2,4,6,6-pentamethylheptane, 2,3,4-trimethyldecane, nonane, 3,4,5,6-tetramethyloctane, and hexadecane may be generated from lipid peroxidation during surgery. Caprolactam and propanoic acid may be more promising exhaled breath biomarkers for lung cancer. PMID:25482491

  8. [Alternative one lung ventilation anesthesia for bilateral thoracoscopic sympathectomy].

    PubMed

    Ho, C S; Kao, M C

    1994-03-01

    Palmar hyperhidrosis (PH) is a common disorder in the oriental subtropical area. There have been many therapeutic methods, such as: oral medication, local treatment and traditional surgical operation, but none of them has proved entirely satisfactory. Since the development of video endoscopic surgery, transthoracic endoscopic sympathectomy has been increasing day by day. This study consisted of 124 PH patients under alternative one lung ventilation anesthesia for bilateral thoracoscopic laser sympathectomy. The age of patients ranged from 13 to 64 years, male 45 and female 79. The average anesthesia duration was 60 min. We used glycopyrrolate 0.03 mg/kg, decardon 1 mg/10 kg for premedication. Induction was with fentanyl 0.07 ml/kg, atracurium 0.6 mg/kg and thiopental 4 mg/kg. Maintenance was with isoflurane in 3L/min. oxygen inhalation. The alternative one lung ventilation anesthesia was achieved with double-lumen endobronchial tube. Fr 37, Fr 35, Fr 28 Sheridan Lt. double-lumen bronchial tube were used depending upon the sex and fudgement of the individual patient. All patients tolerated the procedure well so that sympathectomy could be performed smoothly and uneventfully. Immediately after the operation, a transient mild to moderate degree of difficult breathing and substernal discomfort were experienced in the majority of patients. These suffering often relieved spontaneously or with some common analgesic.

  9. Effect of regional lung inflation on ventilation heterogeneity at different length scales during mechanical ventilation of normal sheep lungs.

    PubMed

    Wellman, Tyler J; Winkler, Tilo; Costa, Eduardo L V; Musch, Guido; Harris, R Scott; Venegas, Jose G; Vidal Melo, Marcos F

    2012-09-01

    Heterogeneous, small-airway diameters and alveolar derecruitment in poorly aerated regions of normal lungs could produce ventilation heterogeneity at those anatomic levels. We modeled the washout kinetics of (13)NN with positron emission tomography to examine how specific ventilation (sV) heterogeneity at different length scales is influenced by lung aeration. Three groups of anesthetized, supine sheep were studied: high tidal volume (Vt; 18.4 ± 4.2 ml/kg) and zero end-expiratory pressure (ZEEP) (n = 6); low Vt (9.2 ± 1.0 ml/kg) and ZEEP (n = 6); and low Vt (8.2 ± 0.2 ml/kg) and positive end-expiratory pressure (PEEP; 19 ± 1 cmH(2)O) (n = 4). We quantified fractional gas content with transmission scans, and sV with emission scans of infused (13)NN-saline. Voxel (13)NN-washout curves were fit with one- or two-compartment models to estimate sV. Total heterogeneity, measured as SD[log(10)(sV)], was divided into length-scale ranges by measuring changes in variance of log(10)(sV), resulting from progressive filtering of sV images. High-Vt ZEEP showed higher sV heterogeneity at <12- (P < 0.01), 12- to 36- (P < 0.01), and 36- to 60-mm (P < 0.05) length scales compared with low-Vt PEEP, with low-Vt ZEEP in between. Increased heterogeneity was associated with the emergence of low sV units in poorly aerated regions, with a high correlation (r = 0.95, P < 0.001) between total heterogeneity and the fraction of lung with slow washout. Regional mean fractional gas content was inversely correlated with regional sV heterogeneity at <12- (r = -0.67), 12- to 36- (r = -0.74), and >36-mm (r = -0.72) length scales (P < 0.001). We conclude that sV heterogeneity at length scales <60 mm increases in poorly aerated regions of mechanically ventilated normal lungs, likely due to heterogeneous small-airway narrowing and alveolar derecruitment. PEEP reduces sV heterogeneity by maintaining lung expansion and airway patency at those small length scales.

  10. Corticosteroids and surfactant change lung function and protein leaks in the lungs of ventilated premature rabbits.

    PubMed Central

    Ikegami, M; Berry, D; elKady, T; Pettenazzo, A; Seidner, S; Jobe, A

    1987-01-01

    Fetal rabbits were treated with corticosteroids by maternal administration for 48 h before delivery at 27 d gestational age. The treated and control rabbits were placed on ventilator-plethysmographs so that ventilation could be adjusted by regulation of tidal volumes to 10-13 ml/kg body wt. [125I]albumin was mixed with fetal lung fluid at birth, alternate rabbits from each litter were treated with Surfactant-TA, and [131I]albumin was injected intravascularly. The movement of the labeled albumins into and out of the alveolar wash and lung tissue was measured after 30 min of ventilation. Corticosteroid treatment (total dose, 0.2 mg/kg betamethasone) significantly decreased the protein leak across the endothelium (P less than 0.001) but increased the protein leak across the epithelium (P less than 0.001). Surfactant treatment decreased both the endothelial and epithelial leaks, and the combination of surfactant and corticosteroid treatments decreased endothelial leaks to 29% of control values and increased compliance more than either treatment alone. The 48-h corticosteroid treatment did not increase alveolar surfactant pool sizes. Corticosteroids significantly changed lung protein leaks independently of surfactant, and improved the response of the preterm lung to surfactant treatments. PMID:3571492

  11. Pressure Dynamic Characteristics of Pressure Controlled Ventilation System of a Lung Simulator

    PubMed Central

    Shi, Yan; Ren, Shuai; Cai, Maolin; Xu, Weiqing; Deng, Qiyou

    2014-01-01

    Mechanical ventilation is an important life support treatment of critically ill patients, and air pressure dynamics of human lung affect ventilation treatment effects. In this paper, in order to obtain the influences of seven key parameters of mechanical ventilation system on the pressure dynamics of human lung, firstly, mechanical ventilation system was considered as a pure pneumatic system, and then its mathematical model was set up. Furthermore, to verify the mathematical model, a prototype mechanical ventilation system of a lung simulator was proposed for experimental study. Last, simulation and experimental studies on the air flow dynamic of the mechanical ventilation system were done, and then the pressure dynamic characteristics of the mechanical system were obtained. The study can be referred to in the pulmonary diagnostics, treatment, and design of various medical devices or diagnostic systems. PMID:25197318

  12. Advanced lung ventilation system (ALVS) with linear respiratory mechanics assumption for waveform optimization of dual-controlled ventilation.

    PubMed

    Montecchia, F; Guerrisi, M; Canichella, A

    2007-03-01

    The present paper describes the functional features of an advanced lung ventilation system (ALVS) properly designed for the optimization of conventional dual-controlled ventilation (DCV), i.e. with pressure-controlled ventilation with ensured tidal or minute volume. Considering the particular clinical conditions of patients treated with controlled ventilation the analysis and synthesis of ALVS control have been performed assuming a linear respiratory mechanics. Moreover, new airways pressure waveforms with more physiological shape can be tested on simulators of respiratory system in order to evaluate their clinical application. This is obtained through the implementation of a compensation procedure making the desired airways pressure waveform independent on patient airways resistance and lung compliance variations along with a complete real-time monitoring of respiratory system parameters leading the ventilator setting. The experimental results obtained with a lung simulator agree with the theoretical ones and show that ALVS performance is useful for the research activity aiming at the improvement of both diagnostic evaluation and therapeutic outcome relative to mechanical ventilation treatments.

  13. Tc-99m MAA lung perfusion scintigraphy performed before and after pulmonary embolectomy for saddle-type pulmonary embolism.

    PubMed

    Shih, W J; Robinson, M C; Huber, C; Pulmano, C

    1995-02-01

    A 58-year-old man had shortness of breath, hypotension, and decreased partial pressure of oxygen (PO2) on the eighteenth day after undergoing craniotomy for a meningioma. Tc-99m MAA pulmonary perfusion scintigraphy showed little perfusion to the right lung and left lower lung and multiple perfusion defects in the left upper lung. Although the results of concurrent chest radiography were negative for pulmonary infiltrates, pulmonary angiography demonstrated a saddle-type embolism. The patient underwent emergency pulmonary artery embolectomy to remove blood clots and organized thromboemboli from the main pulmonary artery and the right and left pulmonary arteries. The patient's postoperative course was uneventful, and a second Tc-99m MAA lung perfusion scan demonstrated marked improvement in lung perfusion.

  14. Ventilation-induced lung injury is not exacerbated by growth restriction in preterm lambs.

    PubMed

    Allison, Beth J; Hooper, Stuart B; Coia, Elise; Zahra, Valerie A; Jenkin, Graham; Malhotra, Atul; Sehgal, Arvind; Kluckow, Martin; Gill, Andrew W; Sozo, Foula; Miller, Suzanne L; Polglase, Graeme R

    2016-02-01

    Intrauterine growth restriction (IUGR) and preterm birth are frequent comorbidities and, combined, increase the risk of adverse respiratory outcomes compared with that in appropriately grown (AG) infants. Potential underlying reasons for this increased respiratory morbidity in IUGR infants compared with AG infants include altered fetal lung development, fetal lung inflammation, increased respiratory requirements, and/or increased ventilation-induced lung injury. IUGR was surgically induced in preterm fetal sheep (0.7 gestation) by ligation of a single umbilical artery. Four weeks later, preterm lambs were euthanized at delivery or delivered and ventilated for 2 h before euthanasia. Ventilator requirements, lung inflammation, early markers of lung injury, and morphological changes in lung parenchymal and vascular structure and surfactant composition were analyzed. IUGR preterm lambs weighed 30% less than AG preterm lambs, with increased brain-to-body weight ratio, indicating brain sparing. IUGR did not induce lung inflammation or injury or alter lung parenchymal and vascular structure compared with AG fetuses. IUGR and AG lambs had similar oxygenation and respiratory requirements after birth and had significant, but similar, increases in proinflammatory cytokine expression, lung injury markers, gene expression, and surfactant phosphatidylcholine species compared with unventilated controls. IUGR does not induce pulmonary structural changes in our model. Furthermore, IUGR and AG preterm lambs have similar ventilator requirements in the immediate postnatal period. This study suggests that increased morbidity and mortality in IUGR infants is not due to altered lung tissue or vascular structure, or to an altered response to early ventilation.

  15. Ventilation-induced lung injury is not exacerbated by growth restriction in preterm lambs.

    PubMed

    Allison, Beth J; Hooper, Stuart B; Coia, Elise; Zahra, Valerie A; Jenkin, Graham; Malhotra, Atul; Sehgal, Arvind; Kluckow, Martin; Gill, Andrew W; Sozo, Foula; Miller, Suzanne L; Polglase, Graeme R

    2016-02-01

    Intrauterine growth restriction (IUGR) and preterm birth are frequent comorbidities and, combined, increase the risk of adverse respiratory outcomes compared with that in appropriately grown (AG) infants. Potential underlying reasons for this increased respiratory morbidity in IUGR infants compared with AG infants include altered fetal lung development, fetal lung inflammation, increased respiratory requirements, and/or increased ventilation-induced lung injury. IUGR was surgically induced in preterm fetal sheep (0.7 gestation) by ligation of a single umbilical artery. Four weeks later, preterm lambs were euthanized at delivery or delivered and ventilated for 2 h before euthanasia. Ventilator requirements, lung inflammation, early markers of lung injury, and morphological changes in lung parenchymal and vascular structure and surfactant composition were analyzed. IUGR preterm lambs weighed 30% less than AG preterm lambs, with increased brain-to-body weight ratio, indicating brain sparing. IUGR did not induce lung inflammation or injury or alter lung parenchymal and vascular structure compared with AG fetuses. IUGR and AG lambs had similar oxygenation and respiratory requirements after birth and had significant, but similar, increases in proinflammatory cytokine expression, lung injury markers, gene expression, and surfactant phosphatidylcholine species compared with unventilated controls. IUGR does not induce pulmonary structural changes in our model. Furthermore, IUGR and AG preterm lambs have similar ventilator requirements in the immediate postnatal period. This study suggests that increased morbidity and mortality in IUGR infants is not due to altered lung tissue or vascular structure, or to an altered response to early ventilation. PMID:26608532

  16. SU-E-J-86: Lobar Lung Function Quantification by PET Galligas and CT Ventilation Imaging in Lung Cancer Patients

    SciTech Connect

    Eslick, E; Kipritidis, J; Keall, P; Bailey, D; Bailey, E

    2014-06-01

    Purpose: The purpose of this study was to quantify the lobar lung function using the novel PET Galligas ([68Ga]-carbon nanoparticle) ventilation imaging and the investigational CT ventilation imaging in lung cancer patients pre-treatment. Methods: We present results on our first three lung cancer patients (2 male, mean age 78 years) as part of an ongoing ethics approved study. For each patient a PET Galligas ventilation (PET-V) image and a pair of breath hold CT images (end-exhale and end-inhale tidal volumes) were acquired using a Siemens Biograph PET CT. CT-ventilation (CT-V) images were created from the pair of CT images using deformable image registration (DIR) algorithms and the Hounsfield Unit (HU) ventilation metric. A comparison of ventilation quantification from each modality was done on the lobar level and the voxel level. A Bland-Altman plot was used to assess the difference in mean percentage contribution of each lobe to the total lung function between the two modalities. For each patient, a voxel-wise Spearmans correlation was calculated for the whole lungs between the two modalities. Results: The Bland-Altman plot demonstrated strong agreement between PET-V and CT-V for assessment of lobar function (r=0.99, p<0.001; range mean difference: −5.5 to 3.0). The correlation between PET-V and CT-V at the voxel level was moderate(r=0.60, p<0.001). Conclusion: This preliminary study on the three patients data sets demonstrated strong agreement between PET and CT ventilation imaging for the assessment of pre-treatment lung function at the lobar level. Agreement was only moderate at the level of voxel correlations. These results indicate that CT ventilation imaging has potential for assessing pre-treatment lobar lung function in lung cancer patients.

  17. Intermedin Stabilized Endothelial Barrier Function and Attenuated Ventilator-induced Lung Injury in Mice

    PubMed Central

    Müller-Redetzky, Holger Christian; Kummer, Wolfgang; Pfeil, Uwe; Hellwig, Katharina; Will, Daniel; Paddenberg, Renate; Tabeling, Christoph; Hippenstiel, Stefan; Suttorp, Norbert; Witzenrath, Martin

    2012-01-01

    Background Even protective ventilation may aggravate or induce lung failure, particularly in preinjured lungs. Thus, new adjuvant pharmacologic strategies are needed to minimize ventilator-induced lung injury (VILI). Intermedin/Adrenomedullin-2 (IMD) stabilized pulmonary endothelial barrier function in vitro. We hypothesized that IMD may attenuate VILI-associated lung permeability in vivo. Methodology/Principal Findings Human pulmonary microvascular endothelial cell (HPMVEC) monolayers were incubated with IMD, and transcellular electrical resistance was measured to quantify endothelial barrier function. Expression and localization of endogenous pulmonary IMD, and its receptor complexes composed of calcitonin receptor-like receptor (CRLR) and receptor activity-modifying proteins (RAMPs) 1–3 were analyzed by qRT-PCR and immunofluorescence in non ventilated mouse lungs and in lungs ventilated for 6 h. In untreated and IMD treated mice, lung permeability, pulmonary leukocyte recruitment and cytokine levels were assessed after mechanical ventilation. Further, the impact of IMD on pulmonary vasoconstriction was investigated in precision cut lung slices (PCLS) and in isolated perfused and ventilated mouse lungs. IMD stabilized endothelial barrier function in HPMVECs. Mechanical ventilation reduced the expression of RAMP3, but not of IMD, CRLR, and RAMP1 and 2. Mechanical ventilation induced lung hyperpermeability, which was ameliorated by IMD treatment. Oxygenation was not improved by IMD, which may be attributed to impaired hypoxic vasoconstriction due to IMD treatment. IMD had minor impact on pulmonary leukocyte recruitment and did not reduce cytokine levels in VILI. Conclusions/Significance IMD may possibly provide a new approach to attenuate VILI. PMID:22563471

  18. SU-E-J-87: Ventilation Weighting Effect On Mean Doses of Both Side Lungs for Patients with Advanced Stage Lung Cancer

    SciTech Connect

    Qu, H; Xia, P; Yu, N

    2015-06-15

    Purpose: To study ventilation weighting effect on radiation doses to both side lungs for patients with advanced stage lung cancer. Methods: Fourteen patients with advanced stage lung cancer were included in this retrospective study. Proprietary software was developed to calculate the lung ventilation map based on 4DCT images acquired for radiation therapy. Two phases of inhale (0%) and exhale (50%) were used for the lung ventilation calculations. For each patient, the CT images were resampled to the same dose calculation resolution of 3mmx3mmx3mm. The ventilation distribution was then normalized by the mean value of the ventilation. The ventilation weighted dose was calculated by applying linearly weighted ventilation to the dose of each pixel. The lung contours were automatically delineated from patient CT image with lung window, excluding the tumor and high density tissues. For contralateral and ipsilateral lungs, the mean lung doses from the original plan and ventilation weighted mean lung doses were compared using two tail t-Test. Results: The average of mean dose was 6.1 ±3.8Gy for the contralateral lungs, and 26.2 ± 14.0Gy for the ipsilateral lungs. The average of ventilation weighted dose was 6.3± 3.8Gy for the contralateral lungs and 24.6 ± 13.1Gy for the ipsilateral lungs. The statistics analysis shows the significance of the mean dose increase (p<0.015) for the contralateral lungs and decrease (p<0.005) for the ipsilateral lungs. Conclusion: Ventilation weighted doses were greater than the un-weighted doses for contralateral lungs and smaller for ipsilateral lungs. This Result may be helpful to understand the radiation dosimetric effect on the lung function and provide planning guidance for patients with advance stage lung cancer.

  19. Lung stress, strain, and energy load: engineering concepts to understand the mechanism of ventilator-induced lung injury (VILI).

    PubMed

    Nieman, Gary F; Satalin, Joshua; Andrews, Penny; Habashi, Nader M; Gatto, Louis A

    2016-12-01

    It was recently shown that acute respiratory distress syndrome (ARDS) mortality has not been reduced in over 15 years and remains ~40 %, even with protective low tidal volume (LVt) ventilation. Thus, there is a critical need to develop novel ventilation strategies that will protect the lung and reduce ARDS mortality. Protti et al. have begun to analyze the impact of mechanical ventilation on lung tissue using engineering methods in normal pigs ventilated for 54 h. They used these methods to assess the impact of a mechanical breath on dynamic and static global lung strain and energy load. Strain is the change in lung volume in response to an applied stress (i.e., Tidal Volume-Vt). This study has yielded a number of exciting new concepts including the following: (1) Individual mechanical breath parameters (e.g., Vt or Plateau Pressure) are not directly correlated with VILI but rather any combination of parameters that subject the lung to excessive dynamic strain and energy/power load will cause VILI; (2) all strain is not equal; dynamic strain resulting in a dynamic energy load (i.e., kinetic energy) is more damaging to lung tissue than static strain and energy load (i.e., potential energy); and (3) a critical consideration is not just the size of the Vt but the size of the lung that is being ventilated by this Vt. This key concept merits attention since our current protective ventilation strategies are fixated on the priority of keeping the Vt low. If the lung is fully inflated, a large Vt is not necessarily injurious. In conclusion, using engineering concepts to analyze the impact of the mechanical breath on the lung is a novel new approach to investigate VILI mechanisms and to help design the optimally protective breath. Data generated using these methods have challenged some of the current dogma surrounding the mechanisms of VILI and of the components in the mechanical breath necessary for lung protection.

  20. Hypertrophic pulmonary osteoarthropathy on bone scintigraphy and 18F-fluorodeoxyglucose positron emission tomography/computed tomography in a patient with lung adenocarcinoma

    PubMed Central

    Cengiz, Arzu; Eren, Mine Şencan; Polatli, Mehmet; Yürekli, Yakup

    2015-01-01

    Hypertrophic pulmonary osteoarthropathy (HPOA) is not an uncommon paraneoplastic syndrome that is frequently associated with lung cancer. A 54-year-old male patient with lung adenocarcinoma underwent bone scintigraphy and fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) scanning for initial staging. Bone scintigraphy revealed increased periosteal activity in lower extremities. FDG PET/CT revealed hypermetabolic right lung mass, mediastinal lymph nodes, and mildly increased periosteal FDG uptake in both femurs and tibias. The findings in lower extremities on bone scan and FDG PET/CT were interpreted as HPOA. PMID:26170569

  1. [Continuous positive airway pressure and high-frequency independent lung ventilation in patients with chronic obstructive lung diseases].

    PubMed

    Fedorova, E A; Vyzhigina, M A; Gal'perin, Iu S; Zhukova, S G; Titov, V A; Godin, A V

    2004-01-01

    The original hypoxemia, hypercapnia, high pulmonary hypertension, high resistance of microcirculation vessels, right volumetric ventricular overload, persistent sub-edema of pulmonary intersticium as well as disparity of ventilation and perfusion between both lungs are the main problems in patients with chronic obstructive disease of the lungs (CODL). Such patients are, as a rule, intolerant to the independent lung collaboration or artificial single-stage ventilation (ASV). Patients with respiratory insufficiency, stages 2 and 3, and with a pronounced impaired type of ventilation have originally a deranged blood gas composition, like hypoxemia or hypercapnia. The application of volume-controllable bi-pulmonary ASV in such patients maintains an adequate gas exchange hemodynamics. However, ASV is accompanied by a significantly reduced gas-exchange function of the single ventilated lung and by essentially worsened intrapulmonary hemodynamics. Therefore, what is needed is to use alternative methods of independent lung ventilation in order to eliminate the gas-exchange impairments and to enable surgical interventions at thoracic organs in such patients (who are intolerant to ASV). A choice of a method and means of oxygen supply to the independent lung is of great importance. The possibility to avoid a high pressure in the airways, while maintaining, simultaneously, an adequate gas exchange, makes the method related with maintaining a constant positive pressure in the airways (CPPA) a priority one in case of CODL patients. The use of constant high-frequency ventilation in the independent lung in patients with obstructive pulmonary lesions does not improve the gas exchange or hemodynamics. Simultaneously, a growing total pulmonary resistance and an increasing pressure in the pulmonary artery are observed. Consequently, the discussed method must not be used for the ventilation support of the independent lung in patients with the obstructive type of the impaired external

  2. Ventilation-Based Decellularization System of the Lung

    PubMed Central

    Tsuchiya, Tomoshi; Mendez, Julio; Calle, Elizabeth A.; Hatachi, Go; Doi, Ryoichiro; Zhao, Liping; Suematsu, Takashi; Nagayasu, Takeshi; Niklason, Laura E.

    2016-01-01

    Abstract The demand for donated organs greatly exceeds the availability. Alternatives to organ donation, such as laboratory-engineered organs, are therefore being developed. One approach is to decellularize the organ and reseed it with selected cells, ideally from the organ recipient. Organ decellularization has typically been attempted by the administration of detergents into vessels such as the portal vein in the liver. However, in the case of the lung, the airway provides another potential administration route, because it has a wide contact area between cells and detergents in the tracheal tree and alveoli. In the present study, we introduce a novel ventilation-based decellularization system for the lung and compare its efficacy to ordinary decellularization systems administering detergent through the pulmonary artery. Rat lungs were decellularized using 500 mL of 3-[(3-cholamidopropyl) dimethylammonio]-1-Propanesulfonate (CHAPS) decellularization solution administrated through the pulmonary artery (vessel group) or through the trachea (airway group). The vessel group was infused CHAPS solution using a gravitational pressure head of 20 cmH2O. The airway group was infused with the detergent using negative pressure and positive end-expiratory pressure, for a volume 10cc with each inspiration in a bioreactor. Pathological and immunohistochemical findings indicated that components of the extracellular matrix (ECM), including proteoglycans, elastic fibers, fibronectin, and laminin, were more decreased in the airway group than in the vessel group. Western blot analysis showed that MHC class I antigen and β-actin were not detected in both decellularized groups. A collagen assay showed that collagen was 70% preserved in both groups compared to native lung. Glycosaminoglycan (GAG) and DNA assays showed that GAG and DNA contents were strongly diminished in both decellularized groups, but those contents were smaller in the airway group than in the vessel group

  3. A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

    SciTech Connect

    Yin, Youbing; Choi, Jiwoong; Hoffman, Eric A.; Tawhai, Merryn H.; Lin, Ching-Long

    2013-07-01

    A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C{sub 1} continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung.

  4. Early mechanical ventilation is deleterious after aspiration-induced lung injury in rabbits.

    PubMed

    Hermon, Michael M; Wassermann, Esther; Pfeiler, Claudia; Pollak, Arnold; Redl, Heinz; Strohmaier, Wolfgang

    2005-01-01

    We investigated whether mechanical ventilation after aspiration is deleterious when started before surfactant therapy. Gas exchange and lung mechanics were measured in rabbits after aspiration either mechanically ventilated before or after lavage with diluted surfactant or Ringer's solution. Lung injury was induced by intratracheal instillation of 2 mL/kg of a betain/HCl pepsin mixture. After 30 min of spontaneous breathing, ventilation was started in 12 rabbits, which were then treated by lavage with diluted surfactant (15 mL/kg body weight; 5.3 mg/mL, group MVpre S) or with Ringer's solution (1 mL/kg; group MVpre R). Another 12 rabbits were treated by lavage while spontaneously breathing and were then connected to the ventilator (MVpost S and MVpost R). Sham control rabbits were mechanically ventilated for 4 h. At the end of experiment, PaO2/FiO2 ratio in MVpost S was five times higher than in MVpre S (P=0.0043). Lung mechanics measurements showed significant difference between MVpre S and MVpost S (P=0.0072). There was histopathologic evidence of decreased lung injury in MVpost S. Immediate initiation of ventilation is harmful when lung injury is induced by aspiration. Further investigations are needed to clarify whether the timing of lavage with diluted surfactant has an impact on the treatment of patients with aspiration or comparable types of direct lung injury. PMID:15614133

  5. Lung hyperinflation by mechanical ventilation versus isolated tracheal aspiration in the bronchial hygiene of patients undergoing mechanical ventilation

    PubMed Central

    Assmann, Crisiela Brum; Vieira, Paulo José Cardoso; Kutchak, Fernanda; Rieder, Marcelo de Mello; Forgiarini, Soraia Genebra Ibrahim; Forgiarini Junior, Luiz Alberto

    2016-01-01

    Objective To determine the efficacy of lung hyperinflation maneuvers via a mechanical ventilator compared to isolated tracheal aspiration for removing secretions, normalizing hemodynamics and improving lung mechanics in patients on mechanical ventilation. Methods This was a randomized crossover clinical trial including patients admitted to the intensive care unit and on mechanical ventilation for more than 48 hours. Patients were randomized to receive either isolated tracheal aspiration (Control Group) or lung hyperinflation by mechanical ventilator (MVH Group). Hemodynamic and mechanical respiratory parameters were measured along with the amount of aspirated secretions. Results A total of 50 patients were included. The mean age of the patients was 44.7 ± 21.6 years, and 31 were male. Compared to the Control Group, the MVH Group showed greater aspirated secretion amount (3.9g versus 6.4g, p = 0.0001), variation in mean dynamic compliance (-1.3 ± 2.3 versus -2.9 ± 2.3; p = 0.008), and expired tidal volume (-0.7 ± 0.0 versus -54.1 ± 38.8, p = 0.0001) as well as a significant decrease in peak inspiratory pressure (0.2 ± 0.1 versus 2.5 ± 0.1; p = 0.001). Conclusion In the studied sample, the MVH technique led to a greater amount of aspirated secretions, significant increases in dynamic compliance and expired tidal volume and a significant reduction in peak inspiratory pressure. PMID:27096673

  6. Measurement of lung function using Electrical Impedance Tomography (EIT) during mechanical ventilation

    NASA Astrophysics Data System (ADS)

    Nebuya, Satoru; Koike, Tomotaka; Imai, Hiroshi; Noshiro, Makoto; Brown, Brian H.; Soma, Kazui

    2010-04-01

    The consistency of regional lung density measurements as estimated by Electrical Impedance Tomography (EIT), in eleven patients supported by a mechanical ventilator, was validated to verify the feasibility of its use in intensive care medicine. There were significant differences in regional lung densities between the normal lung and diseased lungs associated with pneumonia, atelectasis and pleural effusion (Steel-Dwass test, p < 0.05). Temporal changes in regional lung density of patients with atelectasis were observed to be in good agreement with the results of clinical diagnosis. These results indicate that it is feasible to obtain a quantitative value for regional lung density using EIT.

  7. Distribution of ventilation in American alligator Alligator mississippiensis

    SciTech Connect

    Bickler, P.E.; Spragg, R.G.; Hartman, M.T.; White, F.N.

    1985-10-01

    The regional distribution of ventilation in the multicameral lung of spontaneously ventilating alligators (Alligator mississippiensis) was studied with TTXe scintigraphy. Frequent gamma camera images of TTXe washin and washout were obtained and processed to allow evaluation of regional ventilation. Washin of TTXe to equilibrium occurred in three to four breaths in anterior, central, and posterior compartments. Washin was most rapid in the posterior compartment and slowest in the anterior. The structure of the lungs and distribution of ventilation of inspired gas is consistent with the rapid radial spread of gas through a parallel arrangement of lung units surrounding the central intrapulmonary bronchus. Washout to equilibrium of TTXe from all compartments occurred within three to four breaths. This rapid washin and washout of gas to all parts of the lung stands in contrast to the lungs of turtles and snakes, in which the caudal air sacs are relatively poorly ventilated.

  8. Efficacy of /sup 67/Ga-scintigraphy in predicting the diagnostic yield of transbronchial lung biopsy in pulmonary sarcoidosis

    SciTech Connect

    Ackart, R.S.; Munzel, T.L.; Rodriguez, J.J.; Donlan, C.J.; Klayton, R.J.; Foreman, D.R.

    1982-07-01

    Nineteen consecutive patients with clinically suspected sarcoidosis underwent /sup 67/Ga-scintigraphy prior to transbronchial lung biopsy (TBLB) to determine if /sup 67/Ga uptake in lung parenchyma would increase the diagnostic yield of the biopsy procedure. Biopsies were obtained from the areas showing parenchymal uptake on the /sup 67/Ga scan in 13 of the 19 patients. In the six patients not demonstrating uptake of /sup 67/Ga in the lung parenchyma, biopsies were obtained at random from the right lower lobe. There was no correlation between /sup 67/Ga uptake in hilar nodes or pulmonary parenchyma tissue and the diagnostic yield from TBLB. Researchers conclude that /sup 67/Ga scanning is neither efficacious nor cost-effective in predicting the diagnostic yield of TBLB in sarcoidosis.

  9. New operational technology of intrauterine ventilation the fetus lungs by breathing gas

    NASA Astrophysics Data System (ADS)

    Urakov, A. L.; Nikityuk, D. B.; Urakova, N. A.; Kasankin, A. A.; Chernova, L. V.; Dementiev, V. B.

    2015-11-01

    New operational technology for elimination intrauterine hypoxia and asphyxia of the fetus using endoscopic artificial ventilation lungs by respiratory gas was developed. For intrauterine ventilation of fetal lung it is proposed to enter into the uterus a special breathing mask and wear it on the head of the fetus using the original endoscopic technology. The breathing mask, developed by us is connected with external breathing apparatus with a hose. The device is called "intrauterine aqualung". Intrauterine aqualung includes a ventilator and breathing circuit with a special fold-out breathing mask that is put on inside the uterus on the head of fetus like a mesh hat. Controlled by ultrasound the technology of the introduction of the mask inside of the uterus through the natural opening in the cervix and technology of putting on the respiratory mask on the head of the fetus with its head previa were developed. The technology intrauterine ventilation of the fetus lungs by respiratory gas was developed.

  10. Genetic Targets of Hydrogen Sulfide in Ventilator-Induced Lung Injury – A Microarray Study

    PubMed Central

    Spassov, Sashko; Pfeifer, Dietmar; Strosing, Karl; Ryter, Stefan; Hummel, Matthias; Faller, Simone; Hoetzel, Alexander

    2014-01-01

    Recently, we have shown that inhalation of hydrogen sulfide (H2S) protects against ventilator-induced lung injury (VILI). In the present study, we aimed to determine the underlying molecular mechanisms of H2S-dependent lung protection by analyzing gene expression profiles in mice. C57BL/6 mice were subjected to spontaneous breathing or mechanical ventilation in the absence or presence of H2S (80 parts per million). Gene expression profiles were determined by microarray, sqRT-PCR and Western Blot analyses. The association of Atf3 in protection against VILI was confirmed with a Vivo-Morpholino knockout model. Mechanical ventilation caused a significant lung inflammation and damage that was prevented in the presence of H2S. Mechanical ventilation favoured the expression of genes involved in inflammation, leukocyte activation and chemotaxis. In contrast, ventilation with H2S activated genes involved in extracellular matrix remodelling, angiogenesis, inhibition of apoptosis, and inflammation. Amongst others, H2S administration induced Atf3, an anti-inflammatory and anti-apoptotic regulator. Morpholino mediated reduction of Atf3 resulted in elevated lung injury despite the presence of H2S. In conclusion, lung protection by H2S during mechanical ventilation is associated with down-regulation of genes related to oxidative stress and inflammation and up-regulation of anti-apoptotic and anti-inflammatory genes. Here we show that Atf3 is clearly involved in H2S mediated protection. PMID:25025333

  11. Transfer factor, lung volumes, resistance and ventilation distribution in healthy adults.

    PubMed

    Verbanck, Sylvia; Van Muylem, Alain; Schuermans, Daniel; Bautmans, Ivan; Thompson, Bruce; Vincken, Walter

    2016-01-01

    Monitoring of chronic lung disease requires reference values of lung function indices, including putative markers of small airway function, spanning a wide age range.We measured spirometry, transfer factor of the lung for carbon monoxide (TLCO), static lung volume, resistance and ventilation distribution in a healthy population, studying at least 20 subjects per sex and per decade between the ages of 20 and 80 years.With respect to the Global Lung Function Initiative reference data, our subjects had average z-scores for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC of -0.12, 0.04 and -0.32, respectively. Reference equations were obtained which could account for a potential dependence of index variability on age and height. This was done for (but not limited to) indices that are pertinent to asthma and chronic obstructive pulmonary disease studies: forced expired volume in 6 s, forced expiratory flow, TLCO, specific airway conductance, residual volume (RV)/total lung capacity (TLC), and ventilation heterogeneity in acinar and conductive lung zones.Deterioration in acinar ventilation heterogeneity and lung clearance index with age were more marked beyond 60 years, and conductive ventilation heterogeneity showed the greatest increase in variability with age. The most clinically relevant deviation from published reference values concerned RV/TLC values, which were considerably smaller than American Thoracic Society/European Respiratory Society-endorsed reference values.

  12. Suppressive oligonucleotides inhibit inflammation in a murine model of mechanical ventilator induced lung injury

    PubMed Central

    Scheiermann, Julia

    2016-01-01

    Background Mechanical ventilation (MV) is commonly used to improve blood oxygenation in critically ill patients and for general anesthesia. Yet the cyclic mechanical stress induced at even moderate ventilation volume settings [tidal volume (Vt) <10 mL/kg] can injure the lungs and induce an inflammatory response. This work explores the effect of treatment with suppressive oligonucleotides (Sup ODN) in a mouse model of ventilator-induced lung injury (VILI). Methods Balb/cJ mice were mechanically ventilated for 4 h using clinically relevant Vt and a positive end-expiratory pressure of 3 cmH2O under 2–3% isoflurane anesthesia. Lung tissue and bronchoalveolar lavage fluid were collected to assess lung inflammation and lung function was monitored using a FlexiVent®. Results MV induced significant pulmonary inflammation characterized by the influx and activation of CD11c+/F4/80+ macrophages and CD11b+/Ly6G+ polymorphonuclear cells into the lung and bronchoalveolar lavage fluid. The concurrent administration of Sup ODN attenuated pulmonary inflammation as evidenced by reduced cellular influx and production of inflammatory cytokines. Oligonucleotide treatment did not worsen lung function as measured by static compliance or resistance. Conclusions Treatment with Sup ODN reduces the lung injury induced by MV in mice. PMID:27746995

  13. Simulating ventilation distribution in heterogenous lung injury using a binary tree data structure.

    PubMed

    Colletti, Ashley A; Amini, Reza; Kaczka, David W

    2011-10-01

    To determine the impact of mechanical heterogeneity on the distribution of regional flows and pressures in the injured lung, we developed an anatomic model of the canine lung comprised of an asymmetric branching airway network, which can be stored as binary tree data structure. The entire tree can be traversed using a recursive flow divider algorithm, allowing for efficient computation of acinar flow and pressure distributions in a mechanically heterogeneous lung. These distributions were found to be highly dependent on ventilation frequency and the heterogeneity of tissue elastances, reflecting the preferential distribution of ventilation to areas of lower regional impedance.

  14. Perfusion and ventilation filters for Fourier-decomposition MR lung imaging.

    PubMed

    Wujcicki, Artur; Corteville, Dominique; Materka, Andrzej; Schad, Lothar R

    2015-03-01

    MR imaging without the use of contrast agents has recently been used for creating perfusion and ventilation functional lung images. The technique incorporates frequency- or wavelet-domain filters to separate the MR signal components. This paper presents a new, subject-adaptive algorithm for perfusion and ventilation filters design. The proposed algorithm uses a lung signal model for separation of the signal components in the frequency domain. Non-stationary lung signals are handled by a short time Fourier transform. This method was applied to sets of 192 and 90 co-registered non-contrast MR lung images measured for five healthy subjects at the rate of 3,33 images per second, using different slice thicknesses. In each case, the resulted perfusion and ventilation images showed a smaller amount of mutual information, when compared to those obtained using the known lowpass/highpass filter approach.

  15. TU-A-12A-02: Novel Lung Ventilation Imaging with Single Energy CT After Single Inhalation of Xenon: Comparison with SPECT Ventilation Images

    SciTech Connect

    Negahdar, M; Yamamoto, T; Shultz, D; Gable, L; Shan, X; Mittra, E; Loo, B; Maxim, P; Diehn, M

    2014-06-15

    Purpose: We propose a novel lung functional imaging method to determine the spatial distribution of xenon (Xe) gas in a single inhalation as a measure of regional ventilation. We compare Xe-CT ventilation to single-photon emission CT (SPECT) ventilation, which is the current clinical reference. Regional lung ventilation information may be useful for the diagnosis and monitoring of pulmonary diseases such as COPD, radiotherapy planning, and assessing the progression of toxicity after radiation therapy. Methods: In an IRB-approved clinical study, Xe-CT and SPECT ventilation scans were acquired for three patients including one patient with severe emphysema and two lung cancer patients treated with radiotherapy. For Xe- CT, we acquired two breath-hold single energy CT images of the entire lung with inspiration of 100% O2 and a mixture of 70% Xe and 30% O2, respectively. A video biofeedback system was used to achieve reproducible breath-holds. We used deformable image registration to align the breathhold images with each other to accurately subtract them, producing a map of the distribution of Xe as a surrogate of lung ventilation. We divided each lung into twelve parts and correlated the Hounsfield unit (HU) enhancement at each part with the SPECT ventilation count of the corresponding part of the lung. Results: The mean of the Pearson linear correlation coefficient values between the Xe-CT and ventilation SPECT count for all three patients were 0.62 (p<0.01). The Xe-CT image had a higher resolution than SPECT, and did not show central airway deposition artifacts that were present in the SPECT image. Conclusion: We developed a rapid, safe, clinically practical, and potentially widely accessible method for regional lung functional imaging. We demonstrated strong correlations between the Xe-CT ventilation image and SPECT ventilation image as the clinical reference. This ongoing study will investigate more patients to confirm this finding.

  16. [Scintigraphy of pulmonary ventilation with 99mTc-DTPA radio-aerosol. I. Semiotics of the static images].

    PubMed

    Maini, C L; Bonetti, M G; Giordano, A; Pistelli, R; Antonelli Incalzi, R; Vecchioli, A; Galli, G

    1986-04-01

    Papers on deposition pattern analyses of radio-aerosol lung scans are few and not easy to interpret as there is a general lack of technical standardization and the number of patients studied is not large. Moreover these reports have been generally obtained with non-hydrosoluble radioaerosols. In the present study 43 patients underwent conventional pulmonary function testing and lung scanning using small droplet (equal or less than 2 microns) polydisperse 99mTc-DTPA radioaerosol produced with the "Settling Bag System"--Medi 400 (Sorin). The scans were analysed by two methods: a semiquantitative method proposed by Taplin (SQT); an original simpler semiquantitative method (SQM). Correlations of SQT and SQM with FEV1 and MEF75 resulted highly significant (p less than 0,001). SQM proved to be superior to SQT as far as reproducibility is concerned. The following conclusions can be drawn: small particle 99mTc-DTPA aerosol can be easily and cheaply produced by a commercial device; such a radioaerosol is well suited for the evaluation of small and large airways patency, as reflected by MEF75 and FEV1 respectively, with a diagnostic yield comparable to non-hydrosoluble radioaerosols; the original semiquantitative description of the deposition patterns proposed and validated in this study is quite easy to implement and it yields a high correlation with pulmonary function tests; moreover such an approach does not require digital data processing; the sensitivity of 99mTc-DTPA for the diagnosis of bronchial obstruction is very high and superior to routine pulmonary function tests; in addition the ventilation scan allows the topographical localization of the obstructions themselves.

  17. Core body temperature control by total liquid ventilation using a virtual lung temperature sensor.

    PubMed

    Nadeau, Mathieu; Micheau, Philippe; Robert, Raymond; Avoine, Olivier; Tissier, Renaud; Germim, Pamela Samanta; Vandamme, Jonathan; Praud, Jean-Paul; Walti, Herve

    2014-12-01

    In total liquid ventilation (TLV), the lungs are filled with a breathable liquid perfluorocarbon (PFC) while a liquid ventilator ensures proper gas exchange by renewal of a tidal volume of oxygenated and temperature-controlled PFC. Given the rapid changes in core body temperature generated by TLV using the lung has a heat exchanger, it is crucial to have accurate and reliable core body temperature monitoring and control. This study presents the design of a virtual lung temperature sensor to control core temperature. In the first step, the virtual sensor, using expired PFC to estimate lung temperature noninvasively, was validated both in vitro and in vivo. The virtual lung temperature was then used to rapidly and automatically control core temperature. Experimentations were performed using the Inolivent-5.0 liquid ventilator with a feedback controller to modulate inspired PFC temperature thereby controlling lung temperature. The in vivo experimental protocol was conducted on seven newborn lambs instrumented with temperature sensors at the femoral artery, pulmonary artery, oesophagus, right ear drum, and rectum. After stabilization in conventional mechanical ventilation, TLV was initiated with fast hypothermia induction, followed by slow posthypothermic rewarming for 1 h, then by fast rewarming to normothermia and finally a second fast hypothermia induction phase. Results showed that the virtual lung temperature was able to provide an accurate estimation of systemic arterial temperature. Results also demonstrate that TLV can precisely control core body temperature and can be favorably compared to extracorporeal circulation in terms of speed.

  18. Dynamic Characteristics of Mechanical Ventilation System of Double Lungs with Bi-Level Positive Airway Pressure Model

    PubMed Central

    Shen, Dongkai; Zhang, Qian

    2016-01-01

    In recent studies on the dynamic characteristics of ventilation system, it was considered that human had only one lung, and the coupling effect of double lungs on the air flow can not be illustrated, which has been in regard to be vital to life support of patients. In this article, to illustrate coupling effect of double lungs on flow dynamics of mechanical ventilation system, a mathematical model of a mechanical ventilation system, which consists of double lungs and a bi-level positive airway pressure (BIPAP) controlled ventilator, was proposed. To verify the mathematical model, a prototype of BIPAP system with a double-lung simulators and a BIPAP ventilator was set up for experimental study. Lastly, the study on the influences of key parameters of BIPAP system on dynamic characteristics was carried out. The study can be referred to in the development of research on BIPAP ventilation treatment and real respiratory diagnostics.

  19. Dynamic Characteristics of Mechanical Ventilation System of Double Lungs with Bi-Level Positive Airway Pressure Model

    PubMed Central

    Shen, Dongkai; Zhang, Qian

    2016-01-01

    In recent studies on the dynamic characteristics of ventilation system, it was considered that human had only one lung, and the coupling effect of double lungs on the air flow can not be illustrated, which has been in regard to be vital to life support of patients. In this article, to illustrate coupling effect of double lungs on flow dynamics of mechanical ventilation system, a mathematical model of a mechanical ventilation system, which consists of double lungs and a bi-level positive airway pressure (BIPAP) controlled ventilator, was proposed. To verify the mathematical model, a prototype of BIPAP system with a double-lung simulators and a BIPAP ventilator was set up for experimental study. Lastly, the study on the influences of key parameters of BIPAP system on dynamic characteristics was carried out. The study can be referred to in the development of research on BIPAP ventilation treatment and real respiratory diagnostics. PMID:27660646

  20. Cigarette smoke ventilation decreases prostaglandin inactivation in rat and hamster lungs

    SciTech Connect

    Maennistoe, J.; Uotila, P.

    1982-06-01

    The effects of cigarette smoke on the metabolism of exogenous PGE2 and PGF2 alpha were investigated in isolated rat and hamster lungs. When isolated lungs from animals were ventilated with cigarette smoke during pulmonary infusion of 100 nmol of PGE2 or PGF2 alpha, the amounts of the 15-keto-metabolites in the perfusion effluent were decreased. Pre-exposure of animals to cigarette smoke daily for 3 weeks did not change the metabolism of PGE2 when the lungs were ventilated with air. Cigarette smoke ventilation of lungs from pre-exposed animals caused, however, a similar decrease in the metabolism of PGE2 as in animals not previously exposed to smoke. After pulmonary injection of 10 nmol of /sup 14/C-PGE2 the radioactivity appeared more rapidly in the effluent during cigarette smoke ventilation suggesting inhibition of the PGE2 uptake mechanism. In rat lungs pulmonary vascular pressor responses to PGE2 and PGF2 alpha were inhibited by smoke ventilation.

  1. Mean lung pressure during adult high-frequency oscillatory ventilation: an experimental study using a lung model.

    PubMed

    Hirayama, Takahiro; Nagano, Osamu; Shiba, Naoki; Yumoto, Tetsuya; Sato, Keiji; Terado, Michihisa; Ugawa, Toyomu; Ichiba, Shingo; Ujike, Yoshihito

    2014-12-01

    In adult high-frequency oscillatory ventilation (HFOV), stroke volume (SV) and mean lung pressure (PLung) are important for lung protection. We measured the airway pressure at the Y-piece and the lung pressure during HFOV using a lung model and HFOV ventilators for adults (R100 and 3100B). The lung model was made of a 20-liter, airtight rigid plastic container (adiabatic compliance: 19.3 ml/cmH2O) with or without a resistor (20 cmH2O/l/sec). The ventilator settings were as follows: mean airway pressure (MAP), 30 cmH2O; frequency, 5-15 Hz (every 1 Hz); airway pressure amplitude (AMP), maximum;and % of inspiratory time (IT), 50% for R100, 33% or 50% for 3100B. The measurements were also performed with an AMP of 2/3 or 1/3 maximum at 5, 10 and 15 Hz. The PLung and the measured MAP were not consistently identical to the setting MAP in either ventilator, and decreasing IT decreased the PLung in 3100B. In conclusion, we must pay attention to the possible discrepancy between the PLung and the setting MAP during adult HFOV. PMID:25519026

  2. MO-A-BRD-05: Evaluation of Composed Lung Ventilation with 4DCT and Image Registration

    SciTech Connect

    Du, K; Bayouth, J; Reinhardt, J; Christensen, G; Zhao, B; Ding, K

    2014-06-15

    Purpose: Regional pulmonary function can be derived using fourdimensional computed tomography (4DCT) combined with deformable image registration. However, only peak inhale and exhale phases have been used thus far while the lung ventilation during intermediate phases is not considered. In our previous work, we have investigated the spatiotemporal heterogeneity of lung ventilation and its dependence on respiration effort. In this study, composed ventilation is introduced using all inspiration phases and compared to direct ventilation. Both methods are evaluated against Xe-CT derived ventilation. Methods: Using an in-house tissue volume preserving deformable image registration, unlike the direct ventilation method, which computes from end expiration to end inspiration, Jacobian ventilation maps were computed from one inhale phase to the next and then composed from all inspiration steps. The two methods were compared in both patients prior to RT and mechanically ventilated sheep subjects. In addition, they wereassessed for the correlation with Xe-CT derived ventilation in sheep subjects. Annotated lung landmarks were used to evaluate the accuracy of original and composed deformation field. Results: After registration, the landmark distance for composed deformation field was always higher than that for direct deformation field (0IN to 100IN average in human: 1.03 vs 1.53, p=0.001, and in sheep: 0.80 vs0.94, p=0.009), and both increased with longer phase interval. Direct and composed ventilation maps were similar in both sheep (gamma pass rate 87.6) and human subjects (gamma pass rate 71.9),and showed consistent pattern from ventral to dorsal when compared to Xe-CT derived ventilation. Correlation coefficient between Xe-CT and composed ventilation was slightly better than the direct method but not significant (average 0.89 vs 0.85, p=0.135). Conclusion: More strict breathing control in sheep subjects may explain higher similarity between direct and composed ventilation

  3. The role of endocrine mechanisms in ventilator-associated lung injury in critically ill patients.

    PubMed

    Penesova, A; Galusova, A; Vigas, M; Vlcek, M; Imrich, R; Majek, M

    2012-07-01

    The critically ill subjects are represented by a heterogeneous group of patients suffering from a life-threatening event of different origin, e.g. trauma, cardiopulmonary failure, surgery or sepsis. The majority of these patients are dependent on the artificial lung ventilation, which means a life-saving chance for them. However, the artificial lung ventilation may trigger ventilation-associated lung injury (VALI). The mechanical ventilation at higher volumes (volutrauma) and pressure (barotrauma) can cause histological changes in the lungs including impairments in the gap and adherens junctions and desmosomes. The injured lung epithelium may lead to an impairment of the surfactant production and function, and this may not only contribute to the pathophysiology of VALI but also to acute respiratory distress syndrome. Other components of VALI are atelectrauma and toxic effects of the oxygen. Collectively, all these effects may result in a lung inflammation associated with a subsequent profibrotic changes, endothelial dysfunction, and activation of the local and systemic endocrine responses such as the renin-angiotensin system (RAS). The present review is aimed to describe some of the pathophysiologic aspects of VALI providing a basis for novel therapeutic strategies in the critically ill patients. PMID:22808908

  4. Lung stress, strain, and energy load: engineering concepts to understand the mechanism of ventilator-induced lung injury (VILI).

    PubMed

    Nieman, Gary F; Satalin, Joshua; Andrews, Penny; Habashi, Nader M; Gatto, Louis A

    2016-12-01

    It was recently shown that acute respiratory distress syndrome (ARDS) mortality has not been reduced in over 15 years and remains ~40 %, even with protective low tidal volume (LVt) ventilation. Thus, there is a critical need to develop novel ventilation strategies that will protect the lung and reduce ARDS mortality. Protti et al. have begun to analyze the impact of mechanical ventilation on lung tissue using engineering methods in normal pigs ventilated for 54 h. They used these methods to assess the impact of a mechanical breath on dynamic and static global lung strain and energy load. Strain is the change in lung volume in response to an applied stress (i.e., Tidal Volume-Vt). This study has yielded a number of exciting new concepts including the following: (1) Individual mechanical breath parameters (e.g., Vt or Plateau Pressure) are not directly correlated with VILI but rather any combination of parameters that subject the lung to excessive dynamic strain and energy/power load will cause VILI; (2) all strain is not equal; dynamic strain resulting in a dynamic energy load (i.e., kinetic energy) is more damaging to lung tissue than static strain and energy load (i.e., potential energy); and (3) a critical consideration is not just the size of the Vt but the size of the lung that is being ventilated by this Vt. This key concept merits attention since our current protective ventilation strategies are fixated on the priority of keeping the Vt low. If the lung is fully inflated, a large Vt is not necessarily injurious. In conclusion, using engineering concepts to analyze the impact of the mechanical breath on the lung is a novel new approach to investigate VILI mechanisms and to help design the optimally protective breath. Data generated using these methods have challenged some of the current dogma surrounding the mechanisms of VILI and of the components in the mechanical breath necessary for lung protection. PMID:27316442

  5. Perioperative lung-protective ventilation strategy reduces postoperative pulmonary complications in patients undergoing thoracic and major abdominal surgery

    PubMed Central

    2016-01-01

    The occurrence of postoperative pulmonary complications is strongly associated with increased hospital mortality and prolonged postoperative hospital stays. Although protective lung ventilation is commonly used in the intensive care unit, low tidal volume ventilation in the operating room is not a routine strategy. Low tidal volume ventilation, moderate positive end-expiratory pressure, and repeated recruitment maneuvers, particularly for high-risk patients undergoing major abdominal surgery, can reduce postoperative pulmonary complications. Facilitating perioperative bundle care by combining prophylactic and postoperative positive-pressure ventilation with intraoperative lung-protective ventilation may be helpful to reduce postoperative pulmonary complications. PMID:26885294

  6. Abnormal ventilation scans in middle-aged smokers. Comparison with tests of overall lung function

    SciTech Connect

    Barter, S.J.; Cunningham, D.A.; Lavender, J.P.; Gibellino, F.; Connellan, S.J.; Pride, N.B.

    1985-07-01

    The uniformity of regional ventilation during tidal breathing has been assessed using continuous inhalation of krypton-81m in 43 male, lifelong nonsmokers and 46 male, current cigarette smokers (mean daily consumption 24.1 cigarettes/day) between 44 and 61 yr of age and with mild or no respiratory symptoms. All subjects had normal chest radiographs. The results of the ventilation scans were compared with tests of overall lung function (spirometry, maximal expiratory flow-volume curves, and single-breath N2 test). Diffuse abnormalities of the ventilation scan were found in 19 (41%) of the 46 smokers but in none of the nonsmokers. Focal abnormalities were found in 7 smokers and 3 nonsmokers. Smokers showed the expected abnormalities in overall lung function (reduced FEV1 and VC, increased single-breath N2 slope, and closing volume), but in individual smokers there was only a weak relation between the severity of abnormality of overall lung function and an abnormal ventilation scan. Abnormal scans could be found when overall lung function was normal and were not invariably found when significant abnormalities in FEV1/VC or N2 slope were present. There was no relation between the presence of chronic expectoration and an abnormal scan. The prognostic significance of an abnormal ventilation scan in such smokers remains to be established.

  7. Successful one-lung ventilation in a patient with the Fontan circulation undergoing thoracoscopic procedure.

    PubMed

    Cvetkovic, Draginja; Ramzy, Wassim; Vitale, Salvatore; Malekan, Ramin; Warsy, Irfan

    2014-12-01

    Over the course of the past 4 decades, the survival of patients with the Fontan circulation has improved and today they often present for noncardiac surgery anesthesia care. In patients with the Fontan circulation, pulmonary blood flow is passive and anesthetic management is directed at reducing pulmonary vascular resistance and maintaining adequate cardiac output. One-lung ventilation can have unfavorable effects on the Fontan circulation due to hypoxia, hypercarbia, and increased airway pressure. We present a case of successful one-lung ventilation in a patient with the Fontan circulation and describe the perioperative anesthetic management.

  8. Retinyl ester synthesis by the isolated perfused-ventilated neonatal rabbit lung.

    PubMed

    Zachman, R D

    1985-01-01

    Retinyl ester is present in lung but it is unknown if retinyl ester synthesis occurs in that organ. In this study, [3H]-Retinol was perfused into the pulmonary artery of isolated-perfused-ventilated neonatal rabbit lungs. Alumina chromatography was used to separate retinol from retinyl ester in hexane extracts of lung tissue. [3H]-Retinyl ester synthesis did occur and was perfusion time and perfusate [3H]-retinol concentration dependent. Documentation of [3H] retinyl ester synthesis was also made by HPLC analysis of the retinyl ester fraction before and after methanolic KOH hydrolysis. Isolated lung clearly can synthesize retinyl ester. PMID:4086204

  9. Magnetic resonance imaging provides sensitive in vivo assessment of experimental ventilator-induced lung injury.

    PubMed

    Kuethe, Dean O; Filipczak, Piotr T; Hix, Jeremy M; Gigliotti, Andrew P; Estépar, Raúl San José; Washko, George R; Baron, Rebecca M; Fredenburgh, Laura E

    2016-08-01

    Animal models play a critical role in the study of acute respiratory distress syndrome (ARDS) and ventilator-induced lung injury (VILI). One limitation has been the lack of a suitable method for serial assessment of acute lung injury (ALI) in vivo. In this study, we demonstrate the sensitivity of magnetic resonance imaging (MRI) to assess ALI in real time in rat models of VILI. Sprague-Dawley rats were untreated or treated with intratracheal lipopolysaccharide or PBS. After 48 h, animals were mechanically ventilated for up to 15 h to induce VILI. Free induction decay (FID)-projection images were made hourly. Image data were collected continuously for 30 min and divided into 13 phases of the ventilatory cycle to make cinematic images. Interleaved measurements of respiratory mechanics were performed using a flexiVent ventilator. The degree of lung infiltration was quantified in serial images throughout the progression or resolution of VILI. MRI detected VILI significantly earlier (3.8 ± 1.6 h) than it was detected by altered lung mechanics (9.5 ± 3.9 h, P = 0.0156). Animals with VILI had a significant increase in the Index of Infiltration (P = 0.0027), and early regional lung infiltrates detected by MRI correlated with edema and inflammatory lung injury on histopathology. We were also able to visualize and quantify regression of VILI in real time upon institution of protective mechanical ventilation. Magnetic resonance lung imaging can be utilized to investigate mechanisms underlying the development and propagation of ALI, and to test the therapeutic effects of new treatments and ventilator strategies on the resolution of ALI.

  10. Bio-inspired, efficient, artificial lung employing air as the ventilating gas.

    PubMed

    Potkay, Joseph A; Magnetta, Michael; Vinson, Abigail; Cmolik, Brian

    2011-09-01

    Artificial lungs have recently been utilized to rehabilitate patients suffering from lung diseases. However, significant advances in gas exchange, biocompatibility, and portability are required to realize their full clinical potential. Here, we have focused on the issues of gas exchange and portability and report a small-scale, microfabricated artificial lung that uses new mathematical modeling and a bio-inspired design to achieve oxygen exchange efficiencies much larger than current devices, thereby enabling air to be utilized as the ventilating gas. This advancement eliminates the need for pure oxygen required by conventional artificial lung systems and is achieved through a device with feature sizes and structure similar to that in the natural lung. This advancement represents a significant step towards creating the first truly portable and implantable artificial lung systems for the ambulatory care of patients suffering from lung diseases.

  11. Acute ischemic optic neuropathy with extended prone position ventilation in a lung transplant recipient.

    PubMed

    Panchabhai, Tanmay S; Bandyopadhyay, Debabrata; Kapoor, Aanchal; Akindipe, Olufemi; Lane, Charles; Krishnan, Sudhir

    2016-01-01

    Prone position ventilation (PPV) improves mortality in severe acute respiratory distress syndrome (ARDS), but outcomes following its use in lung transplant recipients are not known. We report the case of a 42-year-old Caucasian man who presented with severe ARDS from Bordetella pertussis, 5 years after bilateral sequential lung transplant for cystic fibrosis. He was managed with PPV for 22 days and had a prolonged ICU stay complicated by hypoxic ischemic optic neuropathy leading to blindness. Since his discharge from the ICU 6 months ago, his FEV1 has recovered to 47% predicted compared to his pre-ICU peak FEV1 of 85% predicted, suggesting recovery of lung function. This is the first report of optic nerve damage and vision loss in patients undergoing PPV. Our report also suggests that, in appropriately selected lung transplant recipients, severe hypoxemia could potentially be managed with prone ventilation. PMID:27051622

  12. Variable versus conventional lung protective mechanical ventilation during open abdominal surgery: study protocol for a randomized controlled trial

    PubMed Central

    2014-01-01

    Background General anesthesia usually requires mechanical ventilation, which is traditionally accomplished with constant tidal volumes in volume- or pressure-controlled modes. Experimental studies suggest that the use of variable tidal volumes (variable ventilation) recruits lung tissue, improves pulmonary function and reduces systemic inflammatory response. However, it is currently not known whether patients undergoing open abdominal surgery might benefit from intraoperative variable ventilation. Methods/Design The PROtective VARiable ventilation trial (‘PROVAR’) is a single center, randomized controlled trial enrolling 50 patients who are planning for open abdominal surgery expected to last longer than 3 hours. PROVAR compares conventional (non-variable) lung protective ventilation (CV) with variable lung protective ventilation (VV) regarding pulmonary function and inflammatory response. The primary endpoint of the study is the forced vital capacity on the first postoperative day. Secondary endpoints include further lung function tests, plasma cytokine levels, spatial distribution of ventilation assessed by means of electrical impedance tomography and postoperative pulmonary complications. Discussion We hypothesize that VV improves lung function and reduces systemic inflammatory response compared to CV in patients receiving mechanical ventilation during general anesthesia for open abdominal surgery longer than 3 hours. PROVAR is the first randomized controlled trial aiming at intra- and postoperative effects of VV on lung function. This study may help to define the role of VV during general anesthesia requiring mechanical ventilation. Trial registration Clinicaltrials.gov NCT01683578 (registered on September 3 3012). PMID:24885921

  13. Composite pseudocolor images: a technique to enhance the visual correlation between ventilation-perfusion lung images

    NASA Astrophysics Data System (ADS)

    Vaz de Carvalho, Carlos; Costa, Antonio A.; Seixas, M.; Ferreira, F. N.; Guedes, M. A.; Amaral, I.

    1993-07-01

    Lung ventilation and perfusion raw nuclear medicine images obtained from a gamma camera can be difficult to analyze on a per si basis. A method to optimize the visual correlation between these images was established through the use of new combination images: Composite Pseudo-Color (CPC) images. The major topic of this study is the assessment of the usefulness of this method in the detection of lung malfunction.

  14. Ventilation patterns of the songbird lung/air sac system during different behaviors

    PubMed Central

    Mackelprang, Rebecca; Goller, Franz

    2013-01-01

    SUMMARY Unidirectional, continuous airflow through the avian lung is achieved through an elaborate air sac system with a sequential, posterior to anterior ventilation pattern. This classical model was established through various approaches spanning passively ventilated systems to mass spectrometry analysis of tracer gas flow into various air sacs during spontaneous breathing in restrained ducks. Information on flow patterns in other bird taxa is missing, and these techniques do not permit direct tests of whether the basic flow pattern can change during different behaviors. Here we use thermistors implanted into various locations of the respiratory system to detect small pulses of tracer gas (helium) to reconstruct airflow patterns in quietly breathing and behaving (calling, wing flapping) songbirds (zebra finch and yellow-headed blackbird). The results illustrate that the basic pattern of airflow in these two species is largely consistent with the model. However, two notable differences emerged. First, some tracer gas arrived in the anterior set of air sacs during the inspiration during which it was inhaled, suggesting a more rapid throughput through the lung than previously assumed. Second, differences in ventilation between the two anterior air sacs emerged during calling and wing flapping, indicating that adjustments in the flow pattern occur during dynamic behaviors. It is unclear whether this modulation in ventilation pattern is passive or active. This technique for studying ventilation patterns during dynamic behaviors proves useful for establishing detailed timing of airflow and modulation of ventilation in the avian respiratory system. PMID:23788706

  15. Ventilation patterns of the songbird lung/air sac system during different behaviors.

    PubMed

    Mackelprang, Rebecca; Goller, Franz

    2013-10-01

    Unidirectional, continuous airflow through the avian lung is achieved through an elaborate air sac system with a sequential, posterior to anterior ventilation pattern. This classical model was established through various approaches spanning passively ventilated systems to mass spectrometry analysis of tracer gas flow into various air sacs during spontaneous breathing in restrained ducks. Information on flow patterns in other bird taxa is missing, and these techniques do not permit direct tests of whether the basic flow pattern can change during different behaviors. Here we use thermistors implanted into various locations of the respiratory system to detect small pulses of tracer gas (helium) to reconstruct airflow patterns in quietly breathing and behaving (calling, wing flapping) songbirds (zebra finch and yellow-headed blackbird). The results illustrate that the basic pattern of airflow in these two species is largely consistent with the model. However, two notable differences emerged. First, some tracer gas arrived in the anterior set of air sacs during the inspiration during which it was inhaled, suggesting a more rapid throughput through the lung than previously assumed. Second, differences in ventilation between the two anterior air sacs emerged during calling and wing flapping, indicating that adjustments in the flow pattern occur during dynamic behaviors. It is unclear whether this modulation in ventilation pattern is passive or active. This technique for studying ventilation patterns during dynamic behaviors proves useful for establishing detailed timing of airflow and modulation of ventilation in the avian respiratory system.

  16. Teaching Ventilation/Perfusion Relationships in the Lung

    ERIC Educational Resources Information Center

    Glenny, Robb W.

    2008-01-01

    This brief review is meant to serve as a refresher for faculty teaching respiratory physiology to medical students. The concepts of ventilation and perfusion matching are some of the most challenging ideas to learn and teach. Some strategies to consider in teaching these concepts are, first, to build from simple to more complex by starting with a…

  17. Interactive effects of mechanical ventilation, inhaled nitric oxide and oxidative stress in acute lung injury.

    PubMed

    Ronchi, Carlos Fernando; Ferreira, Ana Lucia Anjos; Campos, Fabio Joly; Kurokawa, Cilmery Suemi; Carpi, Mario Ferreira; Moraes, Marcos Aurélio; Bonatto, Rossano Cesar; Yeum, Kyung-Jin; Fioretto, Jose Roberto

    2014-01-01

    To compare conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation (HFOV), with/without inhaled nitric oxide (iNO), for oxygenation, inflammation, antioxidant/oxidative stress status, and DNA damage in a model of acute lung injury (ALI). Lung injury was induced by tracheal infusion of warm saline. Rabbits were ventilated at [Formula: see text] 1.0 and randomly assigned to one of five groups. Overall antioxidant defense/oxidative stress was assessed by total antioxidant performance assay, and DNA damage by comet assay. Ventilatory and hemodynamic parameters were recorded every 30min for 4h. ALI groups showed worse oxygenation than controls after lung injury. After 4h of mechanical ventilation, HFOV groups presented significant improvements in oxygenation. HFOV with and without iNO, and CMV with iNO showed significantly increased antioxidant defense and reduced DNA damage than CMV without iNO. Inhaled nitric oxide did not beneficially affect HFOV in relation to antioxidant defense/oxidative stress and pulmonary DNA damage. Overall, lung injury was reduced using HFOV or CMV with iNO. PMID:24148688

  18. Non-invasive ventilation in prone position for refractory hypoxemia after bilateral lung transplantation.

    PubMed

    Feltracco, Paolo; Serra, Eugenio; Barbieri, Stefania; Persona, Paolo; Rea, Federico; Loy, Monica; Ori, Carlo

    2009-01-01

    Temporary graft dysfunction with gas exchange abnormalities is a common finding during the postoperative course of a lung transplant and is often determined by the post-reimplantation syndrome. Supportive measures including oxygen by mask, inotropes, diuretics, and pulmonary vasodilators are usually effective in non-severe post-reimplantation syndromes. However, in less-responsive clinical pictures, tracheal intubation with positive pressure ventilation, or non-invasive positive pressure ventilation (NIV), is necessary. We report on the clinical course of two patients suffering from refractory hypoxemia due to post-reimplantation syndrome treated with NIV in the prone and Trendelenburg positions. NIV was well tolerated and led to resolution of atelectactic areas and dishomogeneous lung infiltrates. Repeated turning from supine to prone under non invasive ventilation determined a stable improvement of gas exchange and prevented a more invasive approach. Even though NIV in the prone position has not yet entered into clinical practice, it could be an interesting option to achieve a better match between ventilation and perfusion. This technique, which we successfully applied in lung transplantation, can be easily extended to other lung diseases with non-recruitable dorso-basal areas.

  19. A General Approach to the Evaluation of Ventilation-Perfusion Ratios in Normal and Abnormal Lungs

    ERIC Educational Resources Information Center

    Wagner, Peter D.

    1977-01-01

    Outlines methods for manipulating multiple gas data so as to gain the greatest amount of insight into the properties of ventilation-perfusion distributions. Refers to data corresponding to normal and abnormal lungs. Uses a two-dimensional framework with the respiratory gases of oxygen and carbon dioxide. (CS)

  20. THE effects of tonic lung inflation on ventilation in the American bullfrog Rana catesbeiana Shaw.

    PubMed

    Sanders, C E; Milsom, W K

    2001-08-01

    This study was designed to determine whether lung inflation stimulates or inhibits breathing in frogs by examining the effect of tonic lung inflation on the 'fictive' breathing pattern of decerebrate, unidirectionally ventilated bullfrogs. Neural discharge was monitored in the trigeminal nerve as an indication of the frequency and force of contraction of the buccal pump, and in the laryngeal branch of the vagus nerve as an indication of glottal opening, and hence fictive lung ventilation. Based on the temporal coordination of discharge in the trigeminal and vagus nerves during naturally occurring breaths it was possible to characterize the fictive breaths as inflation, deflation or balanced breaths. Increasing lung inflation increased absolute breathing frequency by reducing the duration of apnea between breaths and promoting a change in breathing pattern from no breathing to single breaths, breathing episodes and, finally, to continuous breathing. Associated with this was a decrease in the amplitude and area of the integrated trigeminal electroneurogram associated with the lung breaths, indicative of a reduction in the force of the buccal pump, and a shift in the timing of the trigeminal and vagal discharge, indicative of a shift from inflation to deflation breaths. Taken together the data suggest that lung deflation produces infrequent, large-amplitude inflation breaths or cycles, but that progressive lung inflation changes the breathing pattern to one of high-frequency attempts to deflate the lungs that are largely passive, and accompanied by contractions of the buccal pump that are no larger than those associated with normal buccal oscillations.

  1. Halothane and isoflurane do not decrease PaO2 during one-lung ventilation in intravenously anesthetized patients.

    PubMed

    Rogers, S N; Benumof, J L

    1985-10-01

    We examined the effect of the inhalational anesthetics halothane (H) and isoflurane (IF) on arterial oxygenation during one-lung ventilation. Twenty consenting patients who required thoracotomy and one-lung ventilation were initially anesthetized only with the intravenous agents, diazepam, fentanyl, pancuronium, metocurine, and infusions of either ketamine or methohexital. A double lumen endotracheal tube was inserted, and each patient's lungs were mechanically ventilated (two-lung ventilation, step 1) with 100% O2 while the patient was in the lateral decubitus position. After the pleura was opened, the nondependent lung was collapsed while the dependent lung continued to be ventilated with 100% O2. After serial PaO2 measurements indicated achievement of stable one-lung ventilation conditions (step 2), intravenous anesthetic agents were discontinued, and either H (n = 10) or IF (n = 10) was administered (step 3) so that PETH = 7.70 +/- 0.61 mm Hg and PETIF = 9.89 +/- 1.08 mm Hg for more than 15 min; at the end of step 3, PaH/PETH = 0.82 (n = 5), PaIF/PETIF = 0.75 (n = 5), PvH/PETH = 0.64 (n = 3), and PvIF/PETIF = 0.68 (n = 3). The inhalational anesthetics were then discontinued, and intravenous agents were reinstituted, allowing PETH and PETIF to decrease below 0.50 mm Hg (step 4). Two-lung ventilation was resumed at the end of the surgical procedure (step 5). PaO2 decreased from 441 +/- 64 to 252 +/- 70 mm Hg when one-lung ventilation was achieved (steps 1-2), and PaO2 increased from 258 +/- 72 to 395 +/- 65 mm Hg when two-lung ventilation was resumed (steps 4-5).(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Hesperetin attenuates ventilator-induced acute lung injury through inhibition of NF-κB-mediated inflammation.

    PubMed

    Ma, Hongzhong; Feng, Xiaoli; Ding, Suchun

    2015-12-15

    Hesperetin, a major bioflavonoid in sweet oranges and lemons, has been reported to have anti-inflammatory properties. However, the effect of hesperetin on ventilator-induced acute lung injury has not been studied. In present study, we investigated the protective effect of hesperetin on ventilator-induced acute lung injury in rats. Rats were orally administered hesperetin (10, 20, or 40mg/kg) two hour before acute lung injury was induced by mechanical ventilation. Rats were then randomly divided into six groups: the lung protective ventilation group (n=20, LV group), injurious ventilation group (n=20, HV group), vehicle-treated injurious ventilation group (n=20, LV+vehicle group), hesperetin (10mg/kg)-treated acute lung injury group (n=20, HV+Hsp (10mg)), hesperetin (20mg/kg)-treated acute lung injury group (n=20, HV+Hsp (20mg)), and hesperetin (40mg/kg)-treated acute lung injury group (n=20, HV+Hsp (40mg)). The lung tissues and bronchoalveolar lavage fluid were isolated for subsequent measurements. Treatment with hesperetin dramatically improved the histology of lung tissue, and reduced the wet/dry ratio, myeloperoxidase activity, protein concentration, and production of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, and MIP-2 in the bronchoalveolar lavage fluid of rats with ventilator-induced acute lung injury. Additionally, our study indicated that this protective effect of hesperetin results from its ability to increase the expression of peroxisome proliferator-activated receptor (PPAR)-γ and inhibit the activation of the nuclear factor (NF)-κB pathway. These results suggest that hesperetin may be a potential novel therapeutic candidate for protection against ventilator-induced acute lung injury.

  3. Improved OCT imaging of lung tissue using a prototype for total liquid ventilation

    NASA Astrophysics Data System (ADS)

    Schnabel, Christian; Meissner, Sven; Koch, Edmund

    2011-06-01

    Optical coherence tomography (OCT) is used for imaging subpleural alveoli in animal models to gain information about dynamic and morphological changes of lung tissue during mechanical ventilation. The quality of OCT images can be increased if the refraction index inside the alveoli is matched to the one of tissue via liquid-filling. Thereby, scattering loss can be decreased and higher penetration depth and tissue contrast can be achieved. Until now, images of liquid-filled lungs were acquired in isolated and fixated lungs only, so that an in vivo measurement situation is not present. To use the advantages of liquid-filling for in vivo imaging of small rodent lungs, it was necessary to develop a liquid ventilator. Perfluorodecalin, a perfluorocarbon, was selected as breathing fluid because of its refraction index being similar to the one of water and the high transport capacity for carbon dioxide and oxygen. The setup is characterized by two independent syringe pumps to insert and withdraw the fluid into and from the lung and a custom-made control program for volume- or pressure-controlled ventilation modes. The presented results demonstrate the liquid-filling verified by optical coherence tomography and intravital microscopy (IVM) and the advantages of liquid-filling to OCT imaging of subpleural alveoli.

  4. Chest tubes, lung entrapment, and failure to wean from the ventilator. Report of three patients with quadriplegia.

    PubMed

    Peterson, W P; Whiteneck, G G; Gerhart, K A

    1994-04-01

    The cases of three patients with traumatic quadriplegia who had been treated with chest tubes are described. Each had been injured at a neurologic level that typically allows weaning from the ventilator, yet none was able to clear refractory atelectasis or become ventilator free. Each underwent surgery during which lung adhesions, entrapment, or deformation at the former chest tube site were identified and corrected. Subsequently, each patient cleared his atelectasis and weaned from the ventilator. These cases suggest the importance of ruling out lung deformity in individuals with ventilator-dependent quadriplegia who have had chest tubes and unexpectedly fail to wean.

  5. Effect of caffeine on respiratory muscle strength and lung function in prematurely born, ventilated infants.

    PubMed

    Kassim, Zainab; Greenough, Anne; Rafferty, Gerrard F

    2009-12-01

    The aims of this study were to determine whether caffeine administration increased respiratory muscle function and if this was associated with lung function improvement in prematurely born infants being weaned from mechanical ventilation. Respiratory muscle function was assessed by measurement of the maximum pressures generated during occlusions at end inspiration (Pemax) and end expiration (Pimax) and lung function by measurement of lung volume (functional residual capacity (FRC)) and respiratory system compliance (CRS) and resistance (RRS) in 18 infants with a median gestational age of 28 (range 24-36) weeks. Measurements were made immediately prior to caffeine administration (baseline) and 6 h later. Six hours after caffeine administration compared to baseline, the median Pemax (p = 0.017), Pimax (p = 0.004), FRC (p < 0.001), CRS (p = 0.002) and RRS (p = 0.004) had significantly improved. Our results suggest that caffeine administration facilitates weaning of prematurely born infants from mechanical ventilation by improving respiratory muscle strength.

  6. Ventilation-perfusion imaging in evaluating regional lung function in nonpenetrating injury to the chest.

    PubMed

    Van Eeden, S F; Klopper, J F; Alheit, B; Bardin, P G

    1989-03-01

    The extent of chest wall and lung injury after nonpenetrating injury to the chest (NIC) determine how aggressive and invasive management modalities should be. We investigated the value of ventilation (133Xe) and perfusion (99mTc) studies as indicators of extent of lung injury in 28 patients with moderate to severe unilateral NIC. The ventilation-perfusion (V/Q) abnormalities were compared with parameters conventionally used to evaluate NIC. All studies were carried out within 24 h of NIC and repeated 24 h later. Ventilation (p less than 0.001) and perfusion (p less than 0.01) abnormalities were more extensive soon after NIC than suggested by chest roentgenograms. Chest x-ray film changes lagged behind V/Q changes on admission and also after 24 h. The extent of ventilation, perfusion, and chest x-ray film abnormalities on admission were all predictors of increased morbidity. V/Q studies may be useful to define the extent as well as the changes in regional lung function following NIC.

  7. Sustained Inflation at Birth Did Not Alter Lung Injury from Mechanical Ventilation in Surfactant-Treated Fetal Lambs

    PubMed Central

    Hillman, Noah H.; Kemp, Matthew W.; Miura, Yuichiro; Kallapur, Suhas G.; Jobe, Alan H.

    2014-01-01

    Background Sustained inflations (SI) are used with the initiation of ventilation at birth to rapidly recruit functional residual capacity and may decrease lung injury and the need for mechanical ventilation in preterm infants. However, a 20 second SI in surfactant-deficient preterm lambs caused an acute phase injury response without decreasing lung injury from subsequent mechanical ventilation. Hypothesis A 20 second SI at birth will decrease lung injury from mechanical ventilation in surfactant-treated preterm fetal lambs. Methods The head and chest of fetal sheep at 126±1 day GA were exteriorized, with tracheostomy and removal of fetal lung fluid prior to treatment with surfactant (300 mg in 15 ml saline). Fetal lambs were randomized to one of four 15 minute interventions: 1) PEEP 8 cmH2O; 2) 20 sec SI at 40 cmH2O, then PEEP 8 cmH2O; 3) mechanical ventilation with 7 ml/kg tidal volume; or 4) 20 sec SI then mechanical ventilation at 7 ml/kg. Fetal lambs remained on placental support for the intervention and for 30 min after the intervention. Results SI recruited a mean volume of 6.8±0.8 mL/kg. SI did not alter respiratory physiology during mechanical ventilation. Heat shock protein (HSP) 70, HSP60, and total protein in lung fluid similarly increased in both ventilation groups. Modest pro-inflammatory cytokine and acute phase responses, with or without SI, were similar with ventilation. SI alone did not increase markers of injury. Conclusion In surfactant treated fetal lambs, a 20 sec SI did not alter ventilation physiology or markers of lung injury from mechanical ventilation. PMID:25419969

  8. Effect of methacholine on peripheral lung mechanics and ventilation heterogeneity in asthma.

    PubMed

    Downie, Sue R; Salome, Cheryl M; Verbanck, Sylvia; Thompson, Bruce R; Berend, Norbert; King, Gregory G

    2013-03-15

    The forced oscillation technique (FOT) and multiple-breath nitrogen washout (MBNW) are noninvasive tests that are potentially sensitive to peripheral airways, with MBNW indexes being especially sensitive to heterogeneous changes in ventilation. The objective was to study methacholine-induced changes in the lung periphery of asthmatic patients and determine how changes in FOT variables of respiratory system reactance (Xrs) and resistance (Rrs) and frequency dependence of resistance (Rrs5-Rrs19) can be linked to changes in ventilation heterogeneity. The contributions of air trapping and airway closure, as extreme forms of heterogeneity, were also investigated. Xrs5, Rrs5, Rrs19, Rrs5-Rrs19, and inspiratory capacity (IC) were calculated from the FOT. Ventilation heterogeneity in acinar and conducting airways, and trapped gas (percent volume of trapped gas at functional residual capacity/vital capacity), were calculated from the MBNW. Measurements were repeated following methacholine. Methacholine-induced airway closure (percent change in forced vital capacity) and hyperinflation (change in IC) were also recorded. In 40 mild to moderate asthmatic patients, increase in Xrs5 after methacholine was predicted by increases in ventilation heterogeneity in acinar airways and forced vital capacity (r(2) = 0.37, P < 0.001), but had no correlation with ventilation heterogeneity in conducting airway increase or IC decrease. Increases in Rrs5 and Rrs5-Rrs19 after methacholine were not correlated with increases in ventilation heterogeneity, trapped gas, hyperinflation, or airway closure. Increased reactance in asthmatic patients after methacholine was indicative of heterogeneous changes in the lung periphery and airway closure. By contrast, increases in resistance and frequency dependence of resistance were not related to ventilation heterogeneity or airway closure and were more indicative of changes in central airway caliber than of heterogeneity. PMID:23372144

  9. Histopathological changes and mRNA expression in lungs of horses after inhalation anaesthesia with different ventilation strategies.

    PubMed

    Hopster, K; Jacobson, B; Hopster-Iversen, C; Rohn, K; Kästner, S B R

    2016-08-01

    Inappropriate mechanical ventilation can lead to ventilator-induced lung injury (VILI). Aim of this study was to evaluate the effects of inhalation anaesthesia and ventilation with and without recruitment (RM) and PEEP titration on alveolar integrity in horses. Twenty-three horses were divided into 4 groups (group OLC ventilated with OLC, group IPPV ventilated with intermittent positive pressure ventilation, group NV non-ventilated, and group C non-anaesthetized control group). After sedation with xylazine and induction with diazepam and ketamine anaesthetized horses were under isoflurane anaesthesia for 5.5h. The horses were euthanized and tissue samples of the dependent and non-dependent lung areas were collected. Histopathological examinations of the lung tissue as well as relative quantification of mRNA of IL-1β, IL-6, iNOS, MMP1 and MMP9 by PCR were performed. Horses of group OLC had significantly less alveolar congestion and atelectasis but greater alveolar overdistension compared to groups NV and IPPV. In groups OLC and group IPPV an increase in IL-1β/6 and MMP1/9 was detected compared to groups NV and C. In conclusion, in breathing spontaneously or IPPV-ventilated horses a higher degree of atelectasis was detected, whereas in OLC-ventilated horses a higher degree of overdistention was present. Elevated levels in IL and MMP might be early signs of VILI in ventilated horses. PMID:27473968

  10. [Ventilation studies of the lung with krypton-81m].

    PubMed

    Klopper, J F; van Heerden, P D; Baard, W P

    1981-08-01

    During a 2-year study period it was found that krypton-81m was useful in routine clinical practice. During this period 1563 technetium-99m perfusion studies and 807 krypton-81m ventilation studies were performed. A distinct advantage of krypton-81m was the ease with which multiple views could be obtained. These views could be directly compared with those of preceding perfusion studies. However, interruptions in the regular supply of rubidium-81/krypton-81m generators affected 17,1% of perfusion studies and xenon-127 should be a suitable substitute for these periods.

  11. Ventilation and oxygenation induce endothelial nitric oxide synthase gene expression in the lungs of fetal lambs.

    PubMed Central

    Black, S M; Johengen, M J; Ma, Z D; Bristow, J; Soifer, S J

    1997-01-01

    At birth, ventilation and oxygenation immediately decrease pulmonary vascular resistance (PVR) and increase pulmonary blood flow (PBF); more gradual changes occur over the next several hours. Nitric oxide, produced by endothelial nitric oxide synthase (eNOS), mediates these gradual changes. To determine how ventilation and oxygenation affect eNOS gene expression, 12 fetal lambs were ventilated for 8 h without changing fetal descending aortic blood gases or pH (rhythmic distension) or with 100% oxygen (O2 ventilation). Vascular pressures and PBF were measured. Total RNA, protein, and tissue sections were prepared from lung tissue for RNase protection assays, Western blotting, and in situ hybridization. O2 ventilation increased PBF and decreased PVR more than rhythmic distension (P < 0.05). Rhythmic distension increased eNOS mRNA expression; O2 ventilation increased eNOS mRNA expression more and increased eNOS protein expression (P < 0.05). To define the mechanisms responsible for these changes, ovine fetal pulmonary arterial endothelial cells were exposed to 1, 21, or 95% O2 or to shear stress. 95% O2 increased eNOS mRNA and protein expression (P < 0.05). Shear stress increased eNOS mRNA and protein expression (P < 0.05). Increased oxygenation but more importantly increased PBF with increased shear stress induce eNOS gene expression and contribute to pulmonary vasodilation after birth. PMID:9294110

  12. Effect of endotracheal suction on lung dynamics in mechanically-ventilated paediatric patients.

    PubMed

    Morrow, Brenda; Futter, Merle; Argent, Andrew

    2006-01-01

    Endotracheal suctioning is performed regularly in ventilated infants and children to remove obstructive secretions. The effect of suctioning on respiratory mechanics is not known. This study aimed to determine the immediate effect of endotracheal suctioning on dynamic lung compliance, tidal volume, and airway resistance in mechanically-ventilated paediatric patients by means of a prospective observational clinical study. Lung mechanics were recorded for five minutes before and five minutes after a standardised suctioning procedure in 78 patients intubated with endotracheal tubes < or = 4.0 mm internal diameter. Twenty-four patients with endotracheal tube leaks > or = 20% were excluded from analysis. There was a significant overall decrease in dynamic compliance (p < 0.001) and mechanical expired tidal volume (p = 0.03) following suctioning with no change in the percentage endotracheal tube leak (p = 0.41). The change in dynamic compliance was directly related to both endotracheal tube and catheter sizes. There was no significant change in expiratory or inspiratory airway resistance following suctioning (p > 0.05). Although the majority of patients (68.5%) experienced a drop in dynamic compliance following suctioning, dynamic compliance increased in 31.5% of patients after the procedure. This study demonstrates that endotracheal suctioning frequently causes an immediate drop in dynamic compliance and expired tidal volume in ventilated children with variable lung pathology, intubated with small endotracheal tubes, probably indicating loss of lung volume caused by the suctioning procedure. There is no evidence that suctioning reduces airway resistance.

  13. The protective effects of glutamine in a rat model of ventilator-induced lung injury

    PubMed Central

    Chen, Chin-Ming; Cheng, Kuo-Chen; Li, Chien-Feng

    2014-01-01

    Background The mortality rate of patients with acute respiratory distress syndrome (ARDS) is still high despite the use of protective ventilatory strategies. We sought to examine the pharmacological effects of glutamine (GLN) in a two-hit model of endotoxin-induced inflammation followed by ventilator-induced lung injury (VILI). We hypothesized that the administration of GLN ameliorates the VILI. Methods Sprague-Dawley rats were anesthetized and given lipopolysaccharide (LPS) intratracheally as a first hit to induce lung inflammation, followed 24 h later by a second hit of mechanical ventilation (MV) with either low tidal volume (6 mL/kg) with 5 cmH2O of positive end-expiratory pressure (PEEP) or high tidal volume (22 mL/kg) with zero PEEP for 4 h. GLN or lactated Ringer’s solution as the placebo was administered intravenously 15 min prior to MV. Results In the LPS-challenged rats ventilated with high tidal volume, the treatment with GLN improved lung injury indices, lung mechanics and cytokine responses compared with the placebo group. Conclusions The administration of GLN given immediately prior to MV may be beneficial in the context of reducing VILI. PMID:25589963

  14. Bixin protects mice against ventilation-induced lung injury in an NRF2-dependent manner

    PubMed Central

    Tao, Shasha; Rojo de la Vega, Montserrat; Quijada, Hector; Wondrak, Georg T.; Wang, Ting; Garcia, Joe G. N.; Zhang, Donna D.

    2016-01-01

    Mechanical ventilation (MV) is a therapeutic intervention widely used in the clinic to assist patients that have difficulty breathing due to lung edema, trauma, or general anesthesia. However, MV causes ventilator-induced lung injury (VILI), a condition characterized by increased permeability of the alveolar-capillary barrier that results in edema, hemorrhage, and neutrophil infiltration, leading to exacerbated lung inflammation and oxidative stress. This study explored the feasibility of using bixin, a canonical NRF2 inducer identified during the current study, to ameliorate lung damage in a murine VILI model. In vitro, bixin was found to activate the NRF2 signaling pathway through blockage of ubiquitylation and degradation of NRF2 in a KEAP1-C151 dependent manner; intraperitoneal (IP) injection of bixin led to pulmonary upregulation of the NRF2 response in vivo. Remarkably, IP administration of bixin restored normal lung morphology and attenuated inflammatory response and oxidative DNA damage following MV. This observed beneficial effect of bixin derived from induction of the NRF2 cytoprotective response since it was only observed in Nrf2+/+ but not in Nrf2−/− mice. This is the first study providing proof-of-concept that NRF2 activators can be developed into pharmacological agents for clinical use to prevent patients from lung injury during MV treatment. PMID:26729554

  15. SU-E-J-120: Comparing 4D CT Computed Ventilation to Lung Function Measured with Hyperpolarized Xenon-129 MRI

    SciTech Connect

    Neal, B; Chen, Q

    2015-06-15

    Purpose: To correlate ventilation parameters computed from 4D CT to ventilation, profusion, and gas exchange measured with hyperpolarized Xenon-129 MRI for a set of lung cancer patients. Methods: Hyperpolarized Xe-129 MRI lung scans were acquired for lung cancer patients, before and after radiation therapy, measuring ventilation, perfusion, and gas exchange. In the standard clinical workflow, these patients also received 4D CT scans before treatment. Ventilation was computed from 4D CT using deformable image registration (DIR). All phases of the 4D CT scan were registered using a B-spline deformable registration. Ventilation at the voxel level was then computed for each phase based on a Jacobian volume expansion metric, yielding phase sorted ventilation images. Ventilation based upon 4D CT and Xe-129 MRI were co-registered, allowing qualitative visual comparison and qualitative comparison via the Pearson correlation coefficient. Results: Analysis shows a weak correlation between hyperpolarized Xe-129 MRI and 4D CT DIR ventilation, with a Pearson correlation coefficient of 0.17 to 0.22. Further work will refine the DIR parameters to optimize the correlation. The weak correlation could be due to the limitations of 4D CT, registration algorithms, or the Xe-129 MRI imaging. Continued development will refine parameters to optimize correlation. Conclusion: Current analysis yields a minimal correlation between 4D CT DIR and Xe-129 MRI ventilation. Funding provided by the 2014 George Amorino Pilot Grant in Radiation Oncology at the University of Virginia.

  16. Lung matrix and vascular remodeling in mechanically ventilated elastin haploinsufficient newborn mice

    PubMed Central

    Hilgendorff, Anne; Parai, Kakoli; Ertsey, Robert; Navarro, Edwin; Jain, Noopur; Carandang, Francis; Peterson, Joanna; Mokres, Lucia; Milla, Carlos; Preuss, Stefanie; Alcazar, Miguel Alejandre; Khan, Suleman; Masumi, Juliet; Ferreira-Tojais, Nancy; Mujahid, Sana; Starcher, Barry; Rabinovitch, Marlene

    2014-01-01

    Elastin plays a pivotal role in lung development. We therefore queried if elastin haploinsufficient newborn mice (Eln+/−) would exhibit abnormal lung structure and function related to modified extracellular matrix (ECM) composition. Because mechanical ventilation (MV) has been linked to dysregulated elastic fiber formation in the newborn lung, we also asked if elastin haploinsufficiency would accentuate lung growth arrest seen after prolonged MV of neonatal mice. We studied 5-day-old wild-type (Eln+/+) and Eln+/− littermates at baseline and after MV with air for 8–24 h. Lungs of unventilated Eln+/− mice contained ∼50% less elastin and ∼100% more collagen-1 and lysyl oxidase compared with Eln+/+ pups. Eln+/− lungs contained fewer capillaries than Eln+/+ lungs, without discernible differences in alveolar structure. In response to MV, lung tropoelastin and elastase activity increased in Eln+/+ neonates, whereas tropoelastin decreased and elastase activity was unchanged in Eln+/− mice. Fibrillin-1 protein increased in lungs of both groups during MV, more in Eln+/− than in Eln+/+ pups. In both groups, MV caused capillary loss, with larger and fewer alveoli compared with unventilated controls. Respiratory system elastance, which was less in unventilated Eln+/− compared with Eln+/+ mice, was similar in both groups after MV. These results suggest that elastin haploinsufficiency adversely impacts pulmonary angiogenesis and that MV dysregulates elastic fiber integrity, with further loss of lung capillaries, lung growth arrest, and impaired respiratory function in both Eln+/+ and Eln+/− mice. Paucity of lung capillaries in Eln+/− newborns might help explain subsequent development of pulmonary hypertension previously reported in adult Eln+/− mice. PMID:25539853

  17. Single-port thoracoscopic surgery for pneumothorax under two-lung ventilation with carbon dioxide insufflation

    PubMed Central

    Han, Kook Nam; Lee, Hyun Joo; Lee, Dong Kyu; Kim, Heezoo; Lim, Sang Ho; Choi, Young Ho

    2016-01-01

    Background The development of single-port thoracoscopic surgery and two-lung ventilation reduced the invasiveness of minor thoracic surgery. This study aimed to evaluate the feasibility and safety of single-port thoracoscopic bleb resection for primary spontaneous pneumothorax using two-lung ventilation with carbon dioxide insufflation. Methods Between February 2009 and May 2014, 130 patients underwent single-port thoracoscopic bleb resection under two-lung ventilation with carbon dioxide insufflation. Access was gained using a commercial multiple-access single port through a 2.5-cm incision; carbon dioxide gas was insufflated through a port channel. A 5-mm thoracoscope, articulating endoscopic devices, and flexible endoscopic staplers were introduced through a multiple-access single port for bulla resection. Results The mean time from endotracheal intubation to incision was 29.2±7.8 minutes, the mean operative time was 30.9±8.2 minutes, and the mean total anesthetic time was 75.5±14.4 minutes. There were no anesthesia-related complications or wound problems. The chest drain was removed after a mean of 3.7±1.4 days and patients were discharged without complications 4.8±1.5 days from the operative day. During a mean 7.5±10.1 months of follow-up, there were five recurrences (3.8%) in operated thorax. Conclusions The anesthetic strategy of single-lumen intubation with carbon dioxide gas insufflation can be a safe and feasible option for single-port thoracoscopic bulla resection as it represents the least invasive surgical option with the potential advantages of reducing operative time and one-lung ventilation-related complications without diminishing surgical outcomes. PMID:27293823

  18. Influence of mechanical ventilation and sepsis on redox balance in diaphragm, myocardium, limb muscles, and lungs.

    PubMed

    Chacon-Cabrera, Alba; Rojas, Yeny; Martínez-Caro, Leticia; Vila-Ubach, Monica; Nin, Nicolas; Ferruelo, Antonio; Esteban, Andrés; Lorente, José A; Barreiro, Esther

    2014-12-01

    Mechanical ventilation (MV), using high tidal volumes (V(T)), causes lung (ventilator-induced lung injury [VILI]) and distant organ injury. Additionally, sepsis is characterized by increased oxidative stress. We tested whether MV is associated with enhanced oxidative stress in sepsis, the commonest underlying condition in clinical acute lung injury. Protein carbonylation and nitration, antioxidants, and inflammation (immunoblotting) were evaluated in diaphragm, gastrocnemius, soleus, myocardium, and lungs of nonseptic and septic (cecal ligation and puncture 24 hours before MV) rats undergoing MV (n = 7 per group) for 150 minutes using 3 different strategies (low V(T) [V(T) = 9 mL/kg], moderate V(T) [V(T) = 15 mL/kg], and high V(T) [V(T) = 25 mL/kg]) and in nonventilated control animals. Compared with nonventilated control animals, in septic and nonseptic rodents (1) diaphragms, limb muscles, and myocardium of high-V(T) rats exhibited a decrease in protein oxidation and nitration levels, (2) antioxidant levels followed a specific fiber-type distribution in slow- and fast-twitch muscles, (3) tumor necrosis factor α (TNF-α) levels were higher in respiratory and limb muscles, whereas no differences were observed in myocardium, and (4) in lungs, protein oxidation was increased, antioxidants were rather decreased, and TNF-α remained unmodified. In this model of VILI, oxidative stress does not occur in distant organs or skeletal muscles of rodents after several hours of MV with moderate-to-high V(T), whereas protein oxidation levels were increased in the lungs of the animals. Inflammatory events were moderately expressed in skeletal muscles and lungs of the MV rats. Concomitant sepsis did not strongly affect the MV-induced effects on muscles, myocardium, or lungs in the rodents.

  19. Breathing in a box: constraints on lung ventilation in giant pterosaurs.

    PubMed

    Geist, Nicholas R; Hillenius, Willem J; Frey, Eberhard; Jones, Terry D; Elgin, Ross A

    2014-12-01

    Pterosaurs were the first vertebrates to achieve active flight, with some derived forms reaching enormous size. Accumulating fossil evidence confirms earlier indications that selection for large size in these flying forms resulted in a light, yet strong skeleton characterized by fusion of many bones of the trunk. However, this process also added mechanical constraints on the mobility of the thorax of large pterosaurs that likely limited the options available for lung ventilation. We present an alternative hypothesis to recent suggestions of an avian-like mechanism of costosternal pumping as the primary means of aspiration. An analysis of the joints among the vertebrae, ribs, sternum, and pectoral girdle of large pterosaurs indicates limited mobility of the ribcage and sternum. Comparisons with modes of lung ventilation in extant amniotes suggests that the stiffened thorax, coupled with mobile gastralia and prepubic bones, may be most consistent with an extracostal mechanism for lung ventilation in large pterodactyloids, perhaps similar to a crocodile-like visceral displacement system. PMID:24357452

  20. Fever Is Associated with Delayed Ventilator Liberation in Acute Lung Injury

    PubMed Central

    Dowdy, David W.; Harrington, Thelma; Chandolu, Satish; Dinglas, Victor D.; Shah, Nirav G.; Colantuoni, Elizabeth; Mendez-Tellez, Pedro A.; Shanholtz, Carl; Hasday, Jeffrey D.; Needham, Dale M.

    2013-01-01

    Background: Acute lung injury (ALI) is characterized by inflammation, leukocyte activation, neutrophil recruitment, endothelial dysfunction, and epithelial injury, which are all affected by fever. Fever is common in the intensive care unit, but the relationship between fever and outcomes in ALI has not yet been studied. We evaluated the association of temperature dysregulation with time to ventilator liberation, ventilator-free days, and in-hospital mortality. Methods: Analysis of a prospective cohort study, which recruited consecutive patients with ALI from 13 intensive care units at four hospitals in Baltimore, Maryland. The relationship of fever and hypothermia with ventilator liberation was assessed with a Cox proportional hazards model. We evaluated the association of temperature during the first 3 days after ALI with ventilator-free days, using multivariable linear regression models, and the association with mortality was evaluated by robust Poisson regression. Measurements and Main Results: Of 450 patients, only 12% were normothermic during the first 3 days after ALI onset. During the first week post-ALI, each additional day of fever resulted in a 33% reduction in the likelihood of successful ventilator liberation (95% confidence interval [CI] for adjusted hazard ratio, 0.57 to 0.78; P < 0.001). Hypothermia was independently associated with decreased ventilator-free days (hypothermia during each of the first 3 d: reduction of 5.58 d, 95% CI: –9.04 to –2.13; P = 0.002) and increased mortality (hypothermia during each of the first 3 d: relative risk, 1.68; 95% CI, 1.06 to 2.66; P = 0.03). Conclusions: Fever and hypothermia are associated with worse clinical outcomes in ALI, with fever being independently associated with delayed ventilator liberation. PMID:24024608

  1. Home kitchen ventilation, cooking fuels, and lung cancer risk in a prospective cohort of never smoking women in Shanghai, China.

    PubMed

    Kim, Christopher; Gao, Yu-Tang; Xiang, Yong-Bing; Barone-Adesi, Francesco; Zhang, Yawei; Hosgood, H Dean; Ma, Shuangge; Shu, Xiao-ou; Ji, Bu-Tian; Chow, Wong-Ho; Seow, Wei Jie; Bassig, Bryan; Cai, Qiuyin; Zheng, Wei; Rothman, Nathaniel; Lan, Qing

    2015-02-01

    Indoor air pollution (IAP) caused by cooking has been associated with lung cancer risk in retrospective case-control studies in developing and rural countries. We report the association of cooking conditions, fuel use, oil use, and risk of lung cancer in a developed urban population in a prospective cohort of women in Shanghai. A total of 71,320 never smoking women were followed from 1996 through 2009 and 429 incident lung cancer cases were identified. Questionnaires collected information on household living and cooking practices for the three most recent residences and utilization of cooking fuel and oil, and ventilation conditions. Cox proportional hazards regression estimated the association for kitchen ventilation conditions, cooking fuels, and use of cooking oils for the risk of lung cancer by hazard ratios (HR) with 95% confidence intervals (95% CI). Ever poor kitchen ventilation was associated with a 49% increase in lung cancer risk (HR: 1.49; 95% CI: 1.15-1.95) compared to never poor ventilation. Ever use of coal was not significantly associated. However, ever coal use with poor ventilation (HR: 1.69; 95% CI: 1.22-2.35) and 20 or more years of using coal with poor ventilation (HR: 2.03; 95% CI: 1.35-3.05) was significantly associated compared to no exposure to coal or poor ventilation. Cooking oil use was not significantly associated. These results demonstrate that IAP from poor ventilation of coal combustion increases the risk of lung cancer and is an important public health issue in cities across China where people may have lived in homes with inadequate kitchen ventilation.

  2. Recruitment Maneuver Does not Increase the Risk of Ventilator Induced Lung Injury

    PubMed Central

    Akıncı, İbrahim Özkan; Atalan, Korkut; Tuğrul, Simru; Özcan, Perihan Ergin; Yılmazbayhan, Dilek; Kıran, Bayram; Basel, Ahmet; Telci, Lutfi; Çakar, Nahit

    2013-01-01

    Background: Mechanical ventilation (MV) may induce lung injury. Aims: To assess and evaluate the role of different mechanical ventilation strategies on ventilator-induced lung injury (VILI) in comparison to a strategy which includes recruitment manoeuvre (RM). Study design: Randomized animal experiment. Methods: Thirty male Sprague-Dawley rats were anaesthetised, tracheostomised and divided into 5 groups randomly according to driving pressures; these were mechanically ventilated with following peak alveolar opening (Pao) and positive end-expiratory pressures (PEEP) for 1 hour: Group 15-0: 15 cmH2O Pao and 0 cmH2O PEEP; Group 30-10: 30 cmH2O Pao and 10 cmH2O PEEP; Group 30-5: 30 cmH2O Pao and 5 cmH2O PEEP; Group 30-5&RM: 30 cmH2O Pao and 5 cmH2O PEEP with additional 45 cmH2O CPAP for 30 seconds in every 15 minutes; Group 45-0: 45 cmH2O Pao and 0 cmH2O PEEP Before rats were sacrificed, blood samples were obtained for the evaluation of cytokine and chemokine levels; then, the lungs were subsequently processed for morphologic evaluation. Results: Oxygenation results were similar in all groups; however, the groups were lined as follows according to the increasing severity of morphometric evaluation parameters: Group 15-0: (0±0.009) < Group 30-10: (0±0.14) < Group 30-5&RM: (1±0.12) < Group 30-5: (1±0.16) < Group 45-0: (2±0.16). Besides, inflammatory responses were the lowest in 30-5&RM group compared to all other groups. TNF-α, IL-1β, IL-6, MCP-1 levels were significantly different between group 30-5&RM and group 15-0 vs. group 45-0 in each group. Conclusion: RM with low PEEP reduces the risk of ventilator-induced lung injury with a lower release of systemic inflammatory mediators in response to mechanical ventilation. PMID:25207105

  3. Ventilation/Perfusion Positron Emission Tomography—Based Assessment of Radiation Injury to Lung

    SciTech Connect

    Siva, Shankar; Hardcastle, Nicholas; Kron, Tomas; Bressel, Mathias; Callahan, Jason; MacManus, Michael P.; Shaw, Mark; Plumridge, Nikki; Hicks, Rodney J.; Steinfort, Daniel; Ball, David L.; Hofman, Michael S.

    2015-10-01

    Purpose: To investigate {sup 68}Ga-ventilation/perfusion (V/Q) positron emission tomography (PET)/computed tomography (CT) as a novel imaging modality for assessment of perfusion, ventilation, and lung density changes in the context of radiation therapy (RT). Methods and Materials: In a prospective clinical trial, 20 patients underwent 4-dimensional (4D)-V/Q PET/CT before, midway through, and 3 months after definitive lung RT. Eligible patients were prescribed 60 Gy in 30 fractions with or without concurrent chemotherapy. Functional images were registered to the RT planning 4D-CT, and isodose volumes were averaged into 10-Gy bins. Within each dose bin, relative loss in standardized uptake value (SUV) was recorded for ventilation and perfusion, and loss in air-filled fraction was recorded to assess RT-induced lung fibrosis. A dose-effect relationship was described using both linear and 2-parameter logistic fit models, and goodness of fit was assessed with Akaike Information Criterion (AIC). Results: A total of 179 imaging datasets were available for analysis (1 scan was unrecoverable). An almost perfectly linear negative dose-response relationship was observed for perfusion and air-filled fraction (r{sup 2}=0.99, P<.01), with ventilation strongly negatively linear (r{sup 2}=0.95, P<.01). Logistic models did not provide a better fit as evaluated by AIC. Perfusion, ventilation, and the air-filled fraction decreased 0.75 ± 0.03%, 0.71 ± 0.06%, and 0.49 ± 0.02%/Gy, respectively. Within high-dose regions, higher baseline perfusion SUV was associated with greater rate of loss. At 50 Gy and 60 Gy, the rate of loss was 1.35% (P=.07) and 1.73% (P=.05) per SUV, respectively. Of 8/20 patients with peritumoral reperfusion/reventilation during treatment, 7/8 did not sustain this effect after treatment. Conclusions: Radiation-induced regional lung functional deficits occur in a dose-dependent manner and can be estimated by simple linear models with 4D-V/Q PET

  4. Lung Protective Ventilation (ARDSNet) versus APRV: Ventilatory Management in a Combined Model of Acute Lung and Brain Injury

    PubMed Central

    Davies, Stephen W.; Leonard, Kenji L.; Falls, Randall K.; Mageau, Ronald P.; Efird, Jimmy T.; Hollowell, Joseph P.; Trainor, Wayne E.; Kanaan, Hilal A.; Hickner, Robert C.; Sawyer, Robert G.; Poulin, Nathaniel R.; Waibel, Brett H.; Toschlog, Eric A.

    2014-01-01

    Background Concomitant lung/brain traumatic injury, results in significant morbidity and mortality. Lung protective ventilation (ARDSNet) has become the standard for managing acute respiratory distress syndrome (ARDS); however, the resulting permissive hypercapnea may compound traumatic brain injury (TBI). Airway pressure release ventilation (APRV) offers an alternative strategy for management of this patient population. APRV was hypothesized to retard the progression of acute lung/brain injury to a greater degree than ARDSNet in a swine model. Methods Yorkshire swine were randomized to ARDSNet, APRV, or sham. Ventilatory settings and pulmonary parameters, vitals, blood gases, quantitative histopathology, and cerebral microdialysis were compared between groups using chi-square, Fisher’s exact, Student’s t-test, Wilcoxon rank-sum, and mixed effects repeated measures modeling. Results 22 swine (17 male, 5 female), weighing 25±6.0kg, were randomized to APRV (n=9), ARDSNet (n=12), or sham (n=1). PaO2/FiO2 (P/F) ratio dropped significantly while intracranial pressure increased significantly for all three groups immediately following lung and brain injury. Over time, peak inspiratory pressure, mean airway pressure, and P/F ratio significantly increased, while total respiratory rate significantly decreased within the APRV group compared to the ARDSNet group. Histopathology did not show significant differences between groups in overall brain or lung tissue injury; however, cerebral microdialysis trends suggested increased ischemia within the APRV group compared to ARDSNet over time. Conclusion Previous studies have not evaluated the effects of APRV in this population. While our macroscopic parameters and histopathology did not observe a significant difference between groups, microdialysis data suggest a trend toward increased cerebral ischemia associated with APRV over time. Additional and future studies should focus on extending the time interval for observation to

  5. Human mesenchymal stem cells attenuate early damage in a ventilated pig model of acute lung injury.

    PubMed

    Moodley, Yuben; Sturm, Marian; Shaw, Kathryn; Shimbori, Chiko; Tan, Dino B A; Kolb, Martin; Graham, Ruth

    2016-07-01

    Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a major cause of global morbidity and mortality. Mesenchymal stem cells (MSC) have shown promise in treating inflammatory lung conditions. We hypothesised that human MSC (hMSC) can improve ALI/ARDS through their anti-inflammatory actions. We subjected pigs (n=6) to intravenous oleic acid (OA) injury, ventilation and hMSC infusion, while the controls (n=5) had intravenous OA, ventilation and an infusion vehicle control. hMSC were infused 1h after the administration of OA. The animals were monitored for additional 4h. Nuclear translocation of nuclear factor-light chain enhancer of activated B cells (NF-κB), a transcription factor that mediates several inflammatory pathways was reduced in hMSC treated pigs compared to controls (p=0.04). There was no significant difference in lung injury, assessed by histological scoring in hMSC treated pigs versus controls (p=0.063). There was no difference in neutrophil counts between hMSC-treated pigs and controls. Within 4h, there was no difference in the levels of IL-10 and IL-8 pre- and post-treatment with hMSC. In addition, there was no difference in hemodynamics, lung mechanics or arterial blood gases between hMSC treated animals and controls. Subsequent studies are required to determine if the observed decrease in inflammatory transcription factors will translate into improvement in inflammation and in physiological parameters over the long term.

  6. Home kitchen ventilation, cooking fuels, and lung cancer risk in a prospective cohort of never smoking women in Shanghai, China

    PubMed Central

    Kim, Christopher; Gao, Yu-Tang; Xiang, Yong-Bing; Barone-Adesi, Francesco; Zhang, Yawei; Hosgood, H. Dean; Ma, Shuangge; Shu, Xiao-ou; Ji, Bu-Tian; Chow, Wong-Ho; Seow, Wei Jie; Bassig, Bryan; Cai, Qiuyin; Zheng, Wei; Rothman, Nathaniel; Lan, Qing

    2014-01-01

    Indoor air pollution (IAP) caused by cooking has been associated with lung cancer risk in retrospective case-control studies in developing and rural countries. We report the association of cooking conditions, fuel use, oil use and risk of lung cancer in a developed urban population in a prospective cohort of women in Shanghai. A total of 71,320 never smoking women were followed from 1996 through 2009 and 429 incident lung cancer cases were identified. Questionnaires collected information on household living and cooking practices for the women’s three most recent residences and utilization of cooking fuel and oil, and ventilation conditions. Cox proportional hazards regression estimated the association for kitchen ventilation conditions, cooking fuels, and use of cooking oils for the risk of lung cancer by hazard ratios (HR) with 95% confidence intervals (95% CI). Ever poor kitchen ventilation was associated with a 49% increase in lung cancer risk (HR: 1.49; 95% CI: 1.15–1.95) compared to never poor ventilation. Ever use of coal was not significantly associated. However, ever coal use with poor ventilation (HR: 1.69; 95% CI: 1.22–2.35) and twenty or more years of using coal (HR: 2.03; 95% CI: 1.35–3.05) was significantly associated compared to no exposure to coal or poor ventilation. Cooking oil use was not significantly associated. These results demonstrate that IAP from poor ventilation of coal combustion increases the risk of lung cancer and is an important public health issue in cities across China where people may have lived in homes with inadequate kitchen ventilation. PMID:24917360

  7. Effects of carbonic anhydrase inhibition on ventilation-perfusion matching in the dog lung.

    PubMed Central

    Swenson, E R; Robertson, H T; Hlastala, M P

    1993-01-01

    Lung carbonic anhydrase (CA) permits rapid pH responses when changes in regional ventilation or perfusion alter airway and alveolar PCO2. These pH changes affect airway and vascular resistances and lung compliance to optimize the balance of regional ventilation (VA) and perfusion (Q) in the lung. To test the hypothesis that these or other CA-dependent mechanisms contribute to VA/Q matching, we administered acetazolamide (25 mg/kg intravenously) to six anesthetized and paralyzed dogs and measured VA/Q relationships before and after CA inhibition by the multiple inert gas elimination technique. Four other groups of dogs were studied to control for possible confounding effects of time under anesthesia and nonselective CA inhibition by acetazolamide: (a) saline placebo as a control for duration of anesthesia, (b) 4% CO2 inhalation to mimic systemic CO2 retention, (c) 1 mg/kg benzolamide (a selective renal CA inhibitor) or 0.5 meq/kg HCl to mimic systemic metabolic acidosis, and (d) 500 mg/kg 4,4'-dinitrostilbene-2,2'-disulfonate (an inhibitor of red cell band 3 protein) to mimic the respiratory acidosis arising from an intracapillary block to rapid mobilization of plasma HCO3- in CO2 exchange. Acetazolamide increased VA/Q mismatch and reduced arterial PO2 measured at equilibrium but these did not occur in the control group. There was no deterioration in VA/Q matching when systemic respiratory acidosis produced either by CO2 inhalation or 4,4'-dinitrostilbene-2,2'-disulfonate or metabolic acidosis (benzolamide or HCl) were imposed to mimic the effects of acetazolamide apart from its inhibition of lung CA. These results support the concept that lung CA subserves VA/Q matching in the normal lung. Images PMID:8349809

  8. Investigation of four-dimensional computed tomography-based pulmonary ventilation imaging in patients with emphysematous lung regions

    NASA Astrophysics Data System (ADS)

    Yamamoto, Tokihiro; Kabus, Sven; Klinder, Tobias; Lorenz, Cristian; von Berg, Jens; Blaffert, Thomas; Loo, Billy W., Jr.; Keall, Paul J.

    2011-04-01

    A pulmonary ventilation imaging technique based on four-dimensional (4D) computed tomography (CT) has advantages over existing techniques. However, physiologically accurate 4D-CT ventilation imaging has not been achieved in patients. The purpose of this study was to evaluate 4D-CT ventilation imaging by correlating ventilation with emphysema. Emphysematous lung regions are less ventilated and can be used as surrogates for low ventilation. We tested the hypothesis: 4D-CT ventilation in emphysematous lung regions is significantly lower than in non-emphysematous regions. Four-dimensional CT ventilation images were created for 12 patients with emphysematous lung regions as observed on CT, using a total of four combinations of two deformable image registration (DIR) algorithms: surface-based (DIRsur) and volumetric (DIRvol), and two metrics: Hounsfield unit (HU) change (VHU) and Jacobian determinant of deformation (VJac), yielding four ventilation image sets per patient. Emphysematous lung regions were detected by density masking. We tested our hypothesis using the one-tailed t-test. Visually, different DIR algorithms and metrics yielded spatially variant 4D-CT ventilation images. The mean ventilation values in emphysematous lung regions were consistently lower than in non-emphysematous regions for all the combinations of DIR algorithms and metrics. VHU resulted in statistically significant differences for both DIRsur (0.14 ± 0.14 versus 0.29 ± 0.16, p = 0.01) and DIRvol (0.13 ± 0.13 versus 0.27 ± 0.15, p < 0.01). However, VJac resulted in non-significant differences for both DIRsur (0.15 ± 0.07 versus 0.17 ± 0.08, p = 0.20) and DIRvol (0.17 ± 0.08 versus 0.19 ± 0.09, p = 0.30). This study demonstrated the strong correlation between the HU-based 4D-CT ventilation and emphysema, which indicates the potential for HU-based 4D-CT ventilation imaging to achieve high physiologic accuracy. A further study is needed to confirm these results.

  9. Autologous transplantation of adipose-derived stromal cells ameliorates ventilator-induced lung injury in rats

    PubMed Central

    2013-01-01

    Background Adipose-derived stromal cells (ADSCs) are a good alternative to multipotent stem cells for regenerative medicine. Low tidal volume (LVT) has proved to be an effective ventilation strategy. However, it is not known if ADSCs and LVT can protect against ventilator-induced lung injury (VILI). This study was aimed to determine the potential of ADSCs and LVT to repair following VILI and to elucidate the mechanisms responsible for this section. Methods A total of 72 rats were randomly assigned into group I (sham group, n = 18), group II (1 h of high tidal volume-ventilated (HVT) 40 mL/kg to peak airway pressures of approximately 35 cm H2O and 100% oxygen, n = 18), group III (1 h of HVT followed by 6 h LVT 6 mL/kg to peak airway pressures of approximately 6 cm H2O and 100% oxygen, n = 18) and group IV (1 h of HVT followed by intravenous injection of 5 × 106 ADSCs, n = 18). All animals were sacrificed 7 after the experiments lasted for 7 hours. Bronchoalveolar lavage fluid (BALF) was collected and lungs were harvested for analysis. Results High tidal volume-ventilated (HVT) rats exhibited typical VILI features compared with sham rats. Lung edema, histological lung injury index, concentrations of total protein, total cell counts, number of neutrophils in bronchoalveolar lavage fluid (BALF), tumor necrosis factor-α, interleukin (IL)-1β, IL-6, IL-10 and transforming growth factor-β1 in BALF were significantly increased in HVT rats. Additionally, gene and protein levels of Na+ channel subunits, Na-K-ATPase pump activity and alveolar fluid clearance were significantly decreased in HVT rats. All these indices of VILI were significantly improved in rats treated with ADSCs. However, compared with ADSCs treatment, LVT strategy had little therapeutic effect in the present study. Conclusion These results may provide valuable insights into the effects of ADSCs in acute lung injury. PMID:23890086

  10. Correlation of measures of regional lung ventilation from 4DCT vs. hyperpolarized helium-3 MR

    NASA Astrophysics Data System (ADS)

    Ding, Kai; Cao, Kunlin; Miller, Wilson; Christensen, Gary; Reinhardt, Joseph; Benedict, Stanley; Libby, Bruce; Sheng, Ke

    2012-03-01

    Radiation induced pulmonary diseases can change the tissue material properties of lung parenchyma and the mechanics of the respiratory system. Recent advances in multi-detector-row CT (MDCT), 4DCT respiratory gating methods, and image processing techniques enable us to follow and measure those changes noninvasively during radiation therapy at a regional level. This study compares the 4DCT based ventilation measurement with the results from hyperpolarized helium-3 MR using the cumulative distribution function maps and the relative overlap (RO) statistic. We show that the similarity between the two measurements increases as the increase of the B-Spline grid spacing and Laplacian weighting which result a smoother ventilation map. The best similarity is found with weighting of 0.5 for linear elasticity and B-Spline grid spacing of 32 mm. Future work is to improve the lung image registration algorithm by incorporating hyperpolarized helium-3 MR information so as to improve its physiological modeling of the lung tissue deformation.

  11. Stable Small Animal Mechanical Ventilation for Dynamic Lung Imaging to Support Computational Fluid Dynamics Models

    SciTech Connect

    Jacob, Rick E.; Lamm, W. J.

    2011-11-08

    Pulmonary computational fluid dynamics models require 3D images to be acquired over multiple points in the dynamic breathing cycle, with no breath holds or changes in ventilatory mechanics. With small animals, these requirements result in long imaging times ({approx}90 minutes), over which lung mechanics, such as compliance, can gradually change if not carefully monitored and controlled. These changes, caused by derecruitment of parenchymal tissue, are manifested as an upward drift in peak inspiratory pressure or by changes in the pressure waveform and/or lung volume over the course of the experiment. We demonstrate highly repeatable mechanical ventilation in anesthetized rats over a long duration for pulmonary CT imaging throughout the dynamic breathing cycle. We describe significant updates to a basic commercial ventilator that was acquired for these experiments. Key to achieving consistent results was the implementation of periodic deep breaths, or sighs, of extended duration to maintain lung recruitment. In addition, continuous monitoring of breath-to-breath pressure and volume waveforms and long-term trends in peak inspiratory pressure and flow provide diagnostics of changes in breathing mechanics.

  12. Evaluation of pulmonary perfusion in lung regions showing isolated xenon-133 ventilation washout defects

    SciTech Connect

    Bushnell, D.L.; Sood, K.B.; Shirazi, P.; Pal, I. )

    1990-08-01

    Xenon-133 washout phase imaging is often used to help determine whether the etiology of a perfusion defect is embolic or due to pulmonary parenchymal pathology, such as chronic obstructive pulmonary disease. This study was designed to evaluate the pulmonary blood flow patterns associated with isolated defects on xenon washout images. Scintigraphic lung studies were reviewed until 100 cases with abnormal ventilation results were obtained. Ventilation abnormalities were compared with the corresponding perfusion scan results at the same anatomic site. Of the 208 individual lung regions with xenon abnormalities, 111 showed isolated washout defects (that is, with normal washin). Ninety-four of these 111 sites showed either normal perfusion or a small, nonsegmental corresponding perfusion defect. Three segmental perfusion defects were noted in association with isolated xenon retention. In each of these cases, however, the patient was felt actually to have pulmonary embolism. Thus, it is recommended that, for interpretation of scintigraphic images in the assessment of pulmonary embolism, lung pathology associated with isolated xenon retention not be considered a potential cause for large or segmental perfusion defects.

  13. Lung ventilation strategies for acute respiratory distress syndrome: a systematic review and network meta-analysis

    PubMed Central

    Wang, Changsong; Wang, Xiaoyang; Chi, Chunjie; Guo, Libo; Guo, Lei; Zhao, Nana; Wang, Weiwei; Pi, Xin; Sun, Bo; Lian, Ailing; Shi, Jinghui; Li, Enyou

    2016-01-01

    To identify the best lung ventilation strategy for acute respiratory distress syndrome (ARDS), we performed a network meta-analysis. The Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE, CINAHL, and the Web of Science were searched, and 36 eligible articles were included. Compared with higher tidal volumes with FiO2-guided lower positive end-expiratory pressure [PEEP], the hazard ratios (HRs) for mortality were 0.624 (95% confidence interval (CI) 0.419–0.98) for lower tidal volumes with FiO2-guided lower PEEP and prone positioning and 0.572 (0.34–0.968) for pressure-controlled ventilation with FiO2-guided lower PEEP. Lower tidal volumes with FiO2-guided higher PEEP and prone positioning had the greatest potential to reduce mortality, and the possibility of receiving the first ranking was 61.6%. Permissive hypercapnia, recruitment maneuver, and low airway pressures were most likely to be the worst in terms of all-cause mortality. Compared with higher tidal volumes with FiO2-guided lower PEEP, pressure-controlled ventilation with FiO2-guided lower PEEP and lower tidal volumes with FiO2-guided lower PEEP and prone positioning ventilation are associated with lower mortality in ARDS patients. Lower tidal volumes with FiO2-guided higher PEEP and prone positioning ventilation and lower tidal volumes with pressure-volume (P–V) static curve-guided individual PEEP are potential optimal strategies for ARDS patients. PMID:26955891

  14. Dynamic ventilation 3He MRI for the quantification of disease in the rat lung.

    PubMed

    Kyriazis, Angelos; Rodriguez, I; Nin, N; Izquierdo-Garcia, J L; Lorente, J A; Perez-Sanchez, J M; Pesic, J; Olsson, L E; Ruiz-Cabello, J

    2012-03-01

    Pulmonary diseases are known to be largely inhomogeneous. To evaluate such inhomogeneities, we are testing an image-based method to measure gas flow in the lung regionally. Dynamic, spin-density-weighted hyperpolarized (3)He MR images performed during slow inhalation of this gas were analyzed to quantify regional inflation rate. This parameter was measured in regions of interest (ROIs) that were defined by a rectangular grid that covered the entire rat lung and grew dynamically with it during its inflation. We used regional inflation rate to quantify elastase-induced emphysema and to differentiate healthy (n = 8) from elastase-treated (n = 9) rat lungs as well as healthy from elastase-treated areas of one rat unilaterally treated with elastase in the left lung. Emphysema was also assessed by gold standard morphological and well-established hyperpolarized (3)He MRI diffusion measurements. Mean values of regional inflation rates were significantly different for healthy and elastase-treated animals and correlated well with the apparent diffusion coefficient of (3)He and morphological measurements. The image-based biomarker inflation rate may be useful for the assessment of regional lung ventilation.

  15. Liquid ventilation improves pulmonary function, gas exchange, and lung injury in a model of respiratory failure.

    PubMed Central

    Hirschl, R B; Parent, A; Tooley, R; McCracken, M; Johnson, K; Shaffer, T H; Wolfson, M R; Bartlett, R H

    1995-01-01

    OBJECTIVE: The authors evaluated gas exchange, pulmonary function, and lung histology during perfluorocarbon liquid ventilation (LV) when compared with gas ventilation (GV) in the setting of severe respiratory failure. BACKGROUND: The efficacy of LV in the setting of respiratory failure has been evaluated in premature animals with surfactant deficiency. However, very little work has been performed in evaluating the efficacy of LV in older animal models of the adult respiratory distress syndrome (ARDS). METHODS: A stable model of lung injury was induced in 12 young sheep weighing 16.4 +/- 3.0 kg using right atrial injection of 0.07 mL/kg of oleic acid followed by saline pulmonary lavage and bijugular venovenous extracorporeal life support (ECLS). For the first 30 minutes on ECLS, all animals were ventilated with gas. Animals were then ventilated with either 15 mL/kg gas (GV, n = 6) or perflubron ([PFC], LV, n = 6) over the ensuing 2.5 hours. Subsequently, ECLS was discontinued in five of the GV animals and five of the LV animals, and GV or LV continued for 1 hour or until death. MAIN FINDINGS: Physiologic shunt (Qps/Qt) was significantly reduced in the LV animals when compared with the GV animals (LV = 31 +/- 10%; GV = 93 +/- 4%; p < 0.001) after 3 hours of ECLS. At the same time point, pulmonary compliance (CT) was significantly increased in the LV group when compared with the GV group (LV = 1.04 +/- 0.19 mL/cm H2O/kg; GV = 0.41 +/- 0.02 mL/cm H2O/kg; p < 0.001). In addition, the ECLS flow rate required to maintain the PaO2 in the 50- to 80-mm Hg range was substantially and significantly lower in the LV group when compared with that of the GV group (LV = 14 +/- 5 mL/kg/min; GV = 87 +/- 15 mL/kg/min; p < 0.001). All of the GV animals died after discontinuation of ECLS, whereas all the LV animals demonstrated effective gas exchange without extracorporeal support for 1 hour (p < 0.01). Lung biopsy light microscopy demonstrated a marked reduction in alveolar hemorrhage

  16. The Effects of Lung Protective Ventilation or Hypercapnic Acidosis on Gas Exchange and Lung Injury in Surfactant Deficient Rabbits

    PubMed Central

    Hummler, Helmut D.; Banke, Katharina; Wolfson, Marla R.; Buonocore, Giuseppe; Ebsen, Michael; Bernhard, Wolfgang; Tsikas, Dimitrios; Fuchs, Hans

    2016-01-01

    Background Permissive hypercapnia has been shown to reduce lung injury in subjects with surfactant deficiency. Experimental studies suggest that hypercapnic acidosis by itself rather than decreased tidal volume may be a key protective factor. Objectives To study the differential effects of a lung protective ventilatory strategy or hypercapnic acidosis on gas exchange, hemodynamics and lung injury in an animal model of surfactant deficiency. Methods 30 anesthetized, surfactant-depleted rabbits were mechanically ventilated (FiO2 = 0.8, PEEP = 7cmH2O) and randomized into three groups: Normoventilation-Normocapnia (NN)-group: tidal volume (Vt) = 7.5 ml/kg, target PaCO2 = 40 mmHg; Normoventilation-Hypercapnia (NH)-group: Vt = 7.5 ml/kg, target PaCO2 = 80 mmHg by increasing FiCO2; and a Hypoventilation-Hypercapnia (HH)-group: Vt = 4.5 ml/kg, target PaCO2 = 80 mmHg. Plasma lactate and interleukin (IL)-8 were measured every 2 h. Animals were sacrificed after 6 h to perform bronchoalveolar lavage (BAL), to measure lung wet-to-dry weight, lung tissue IL-8, and to obtain lung histology. Results PaO2 was significantly higher in the HH-group compared to the NN-group (p<0.05), with values of the NH-group between the HH- and NN-groups. Other markers of lung injury (wet-dry-weight, BAL-Protein, histology-score, plasma-IL-8 and lung tissue IL-8) resulted in significantly lower values for the HH-group compared to the NN-group and trends for the NH-group towards lower values compared to the NN-group. Lactate was significantly lower in both hypercapnia groups compared to the NN-group. Conclusion Whereas hypercapnic acidosis may have some beneficial effects, a significant effect on lung injury and systemic inflammatory response is dependent upon a lower tidal volume rather than resultant arterial CO2 tensions and pH alone. PMID:26840779

  17. Plasma membrane stress failure in ventilator-injured lungs. A hypothesis about osmoregulation and the pharmacologic protection of the lungs against deformation injury.

    PubMed

    Mendez, Jose L; Rickman, Otis B; Hubmayr, Rolf D

    2004-01-01

    Cell injury and repair are invariable consequences of mechanical ventilation with large tidal volumes. Rate and amplitude of deforming stress affect numerous cell metabolic functions including host defense and wound repair. Recently, we have focused on the role of plasma membrane stress failure as a trigger for a pro-inflammatory response in mechanically ventilated lungs. We have developed both cell- and organ-based models to study this problem. Alveolar epithelial cells that are exposed to deforming stresses seek to maintain sublytic plasma membrane tension and may activate mechanisms of cell surface area regulation to control membrane tension. Interventions which either increase the amount of excess plasma membrane or enhance lipid trafficking should be cytoprotective against deformation induced injury. Osmotic manipulation may be one such intervention. Preconditioning the lungs with anisosmotic solutions may allow the cells to recruit excess plasma membrane and thus be more resistant to ventilator-induced lung injury. PMID:15218285

  18. SU-E-J-90: Lobar-Level Lung Ventilation Analysis Using 4DCT and Deformable Image Registration

    SciTech Connect

    Du, K; Bayouth, J; Patton, T; Reinhardt, J; Gerard, S; Christensen, G; Zhao, B; Pan, Y

    2015-06-15

    Purpose: To assess regional changes in human lung ventilation and mechanics using four-dimensional computed tomography (4DCT) and deformable image registration. This work extends our prior analysis of the entire lung to a lobe-based analysis. Methods: 4DCT images acquired from 20 patients prior to radiation therapy (RT) were used for this analysis. Jacobian ventilation and motion maps were computed from the displacement field after deformable image registration between the end of expiration breathing phase and the end of inspiration breathing phase. The lobes were manually segmented on the reference phase by a medical physicist expert. The voxel-by-voxel ventilation and motion magnitude for all subjects were grouped by lobes and plotted into cumulative voxel frequency curves respectively. In addition, to eliminate the effect of different breathing efforts across subjects, we applied the inter-subject equivalent lung volume (ELV) method on a subset of the cohort and reevaluated the lobar ventilation. Results: 95% of voxels in the lung are expanding during inspiration. However, some local regions of lung tissue show far more expansion than others. The greatest expansion with respiration occurs within the lower lobes; between exhale and inhale the median expansion in lower lobes is approximately 15%, while the median expansion in upper lobes is 10%. This appears to be driven by a subset of lung tissues within the lobe that have greater expansion; twice the number of voxels in the lower lobes (20%) expand by > 30% when compared to the upper lobes (10%). Conclusion: Lung ventilation and motion show significant difference on the lobar level. There are different lobar fractions of driving voxels that contribute to the major expansion of the lung. This work was supported by NIH grant CA166703.

  19. Measuring interfraction and intrafraction lung function changes during radiation therapy using four-dimensional cone beam CT ventilation imaging

    SciTech Connect

    Kipritidis, John Keall, Paul J.; Hugo, Geoffrey; Weiss, Elisabeth; Williamson, Jeffrey

    2015-03-15

    Purpose: Adaptive ventilation guided radiation therapy could minimize the irradiation of healthy lung based on repeat lung ventilation imaging (VI) during treatment. However the efficacy of adaptive ventilation guidance requires that interfraction (e.g., week-to-week), ventilation changes are not washed out by intrafraction (e.g., pre- and postfraction) changes, for example, due to patient breathing variability. The authors hypothesize that patients undergoing lung cancer radiation therapy exhibit larger interfraction ventilation changes compared to intrafraction function changes. To test this, the authors perform the first comparison of interfraction and intrafraction lung VI pairs using four-dimensional cone beam CT ventilation imaging (4D-CBCT VI), a novel technique for functional lung imaging. Methods: The authors analyzed a total of 215 4D-CBCT scans acquired for 19 locally advanced non-small cell lung cancer (LA-NSCLC) patients over 4–6 weeks of radiation therapy. This set of 215 scans was sorted into 56 interfraction pairs (including first day scans and each of treatment weeks 2, 4, and 6) and 78 intrafraction pairs (including pre/postfraction scans on the same-day), with some scans appearing in both sets. VIs were obtained from the Jacobian determinant of the transform between the 4D-CBCT end-exhale and end-inhale images after deformable image registration. All VIs were deformably registered to their corresponding planning CT and normalized to account for differences in breathing effort, thus facilitating image comparison in terms of (i) voxelwise Spearman correlations, (ii) mean image differences, and (iii) gamma pass rates for all interfraction and intrafraction VI pairs. For the side of the lung ipsilateral to the tumor, we applied two-sided t-tests to determine whether interfraction VI pairs were more different than intrafraction VI pairs. Results: The (mean ± standard deviation) Spearman correlation for interfraction VI pairs was r{sup -}{sub Inter

  20. Measuring interfraction and intrafraction lung function changes during radiation therapy using four-dimensional cone beam CT ventilation imaging

    PubMed Central

    Kipritidis, John; Hugo, Geoffrey; Weiss, Elisabeth; Williamson, Jeffrey; Keall, Paul J.

    2015-01-01

    Purpose: Adaptive ventilation guided radiation therapy could minimize the irradiation of healthy lung based on repeat lung ventilation imaging (VI) during treatment. However the efficacy of adaptive ventilation guidance requires that interfraction (e.g., week-to-week), ventilation changes are not washed out by intrafraction (e.g., pre- and postfraction) changes, for example, due to patient breathing variability. The authors hypothesize that patients undergoing lung cancer radiation therapy exhibit larger interfraction ventilation changes compared to intrafraction function changes. To test this, the authors perform the first comparison of interfraction and intrafraction lung VI pairs using four-dimensional cone beam CT ventilation imaging (4D-CBCT VI), a novel technique for functional lung imaging. Methods: The authors analyzed a total of 215 4D-CBCT scans acquired for 19 locally advanced non-small cell lung cancer (LA-NSCLC) patients over 4–6 weeks of radiation therapy. This set of 215 scans was sorted into 56 interfraction pairs (including first day scans and each of treatment weeks 2, 4, and 6) and 78 intrafraction pairs (including pre/postfraction scans on the same-day), with some scans appearing in both sets. VIs were obtained from the Jacobian determinant of the transform between the 4D-CBCT end-exhale and end-inhale images after deformable image registration. All VIs were deformably registered to their corresponding planning CT and normalized to account for differences in breathing effort, thus facilitating image comparison in terms of (i) voxelwise Spearman correlations, (ii) mean image differences, and (iii) gamma pass rates for all interfraction and intrafraction VI pairs. For the side of the lung ipsilateral to the tumor, we applied two-sided t-tests to determine whether interfraction VI pairs were more different than intrafraction VI pairs. Results: The (mean ± standard deviation) Spearman correlation for interfraction VI pairs was r¯Inter=0.52±0

  1. Effects of MMP-9 inhibition by doxycycline on proteome of lungs in high tidal volume mechanical ventilation-induced acute lung injury

    PubMed Central

    2010-01-01

    Background Although mechanical ventilation (MV) is a major supportive therapy for patients with acute respiratory distress syndrome, it may result in side effects including lung injury. In this study we hypothesize that MMP-9 inhibition by doxycycline might reduce MV-related lung damage. Using a proteomic approach we identified the pulmonary proteins altered in high volume ventilation-induced lung injury (VILI). Forty Wistar rats were randomized to an orally pretreated with doxycycline group (n = 20) or to a placebo group (n = 20) each of which was followed by instrumentation prior to either low or high tidal volume mechanical ventilation. Afterwards, animals were euthanized and lungs were harvested for subsequent analyses. Results Mechanical function and gas exchange parameters improved following treatment with doxycycline in the high volume ventilated group as compared to the placebo group. Nine pulmonary proteins have shown significant changes between the two biochemically analysed (high volume ventilated) groups. Treatment with doxycycline resulted in a decrease of pulmonary MMP-9 activity as well as in an increase in the levels of soluble receptor for advanced glycation endproduct, apoliporotein A-I, peroxiredoxin II, four molecular forms of albumin and two unnamed proteins. Using the pharmacoproteomic approach we have shown that treatment with doxycycline leads to an increase in levels of several proteins, which could potentially be part of a defense mechanism. Conclusion Administration of doxycycline might be a significant supportive therapeutic strategy in prevention of VILI. PMID:20205825

  2. Different approaches for quantifying ventilation distribution and lung tissue properties by functional EIT.

    PubMed

    Hahn, G; Dittmar, J; Just, A; Quintel, M; Hellige, G

    2010-08-01

    We investigated five different methods which can be applied to quantitatively construct functional tomograms of the lungs. The focus was on the sensitivity of functional tomograms to errors in acquired data. To quantify this sensitivity, theoretical, error-free data sets of well-known properties were artificially generated based on a 'living thorax model'. Physiological time courses and a typical distribution of errors caused by a typical Goe-MF II EIT system were used for the calculations which encompassed a range up to 50 times greater than the initial error level (4 microV(rms max)-400 microV(rms max)). Additionally, low-pass filtering and principal component analysis (PCA) were used to quantify the effect of preprocessing the raw data. The results demonstrate that all methods based on fitting the local to the global time course were superior to the common functional tomograms utilizing standard deviation or maximum and minimum detection. Ventilation distribution was best quantified by the so-called VT methods. Filling capacity--a lung tissue property--was least dependent on increasing error levels. The errors introduced by filtering are significant with respect to a quantitative analysis of ventilation distribution. A preprocessing of raw data by applying a PCA performed well on the data sets which had been constructed but were, nonetheless, realistic. This approach appears to be highly promising for application on real data which is known to be erroneous.

  3. Conversion of choline to phosphatidylcholine in the isolated-ventilated-perfused neonatal rabbit lung.

    PubMed

    Zachman, R D; Cotter, P W; Tsao, F H

    1983-01-01

    The isolated-ventilated-perfused neonatal rabbit lung model was used to study pulse dosed 14C-choline incorporation into 14C-phosphatidylcholine (PC) and 14C-disaturated phosphatidylcholine (DSPC). 14C-PC and 14C-DSPC synthesis were linearly dependent upon perfusion time to 30 min and upon the pulse dose of 14C-choline of 20-250 nmol at both 10 and 30 min of perfusion. 2-3% of the pulse-dosed choline was taken up by the lung. The water-soluble metabolites of choline found in lung after 10-30 min of perfusion were: choline, 50-60%; betaine 2.4-3.0%; phosphorylcholine, 26-41%, and CDP-choline, trace-10%. 1-day-old perfused lungs incorporated pulse-dosed 14C-choline into 14C-PC and 14C-DSPC at slightly higher rates than at 10 days old. Newborn rabbits receiving an intraperitoneal injection of 0.1 mg dexamethasone/100 g body weight 16 and 22 h prior to perfusion incorporated significantly more 14C-choline into 14C-PC and 14C-DSPC than saline-injected controls. PMID:6626622

  4. Lung function and ventilation inhomogeneity in rat lungs after allergen challenge.

    PubMed

    Sánchez-Cifuentes, M V; Rubio, M L; Ortega, M; Peces-Barba, G; Paiva, M; Verbanck, S; Mangado, N G

    2000-03-01

    We studied the early response to ovalbumin challenge in sensitized Brown-Norway rats through its effect on N(2), He, and SF(6) phase III slopes of the single-breath washout and on indexes of lung function. Sensitized rats showed varying degrees of response in terms of pulmonary pressure (PL), with increases ranging between 125 and 225% of baseline. The sensitized rats presented decreased quasistatic compliance, forced vital capacity, and end-expiratory flow, with all three lung function indexes showing a significant negative correlation with corresponding PL values. They also showed significant positive correlations of PL with the N(2), He, and SF(6) phase III slopes, reflecting diffusion-convection-dependent inhomogeneities generated by conformation changes throughout the entire rat lung. In addition, the rats showing the most marked PL increases (>150% baseline PL) also revealed a reversal of the SF(6)-He slope difference because of a more marked SF(6) than He slope increase. This latter finding suggests that the degree of structural heterogeneity during early response is even more marked in the most peripheral rat lung generations.

  5. CT Fluoroscopy-Guided Lung Biopsy with Novel Steerable Biopsy Canula: Ex-Vivo Evaluation in Ventilated Porcine Lung Explants

    SciTech Connect

    Schaefer, Philipp J. Fabel, Michael; Bolte, Hendrik; Schaefer, Fritz K. W.; Jahnke, Thomas; Heller, Martin; Lammer, Johannes; Biederer, Juergen

    2010-08-15

    The purpose was to evaluate ex-vivo a prototype of a novel biopsy canula under CT fluoroscopy-guidance in ventilated porcine lung explants in respiratory motion simulations. Using an established chest phantom for porcine lung explants, n = 24 artificial lesions consisting of a fat-wax-Lipiodol mixture (approx. 70HU) were placed adjacent to sensible structures such as aorta, pericardium, diaphragm, bronchus and pulmonary artery. A piston pump connected to a reservoir beneath a flexible silicone reconstruction of a diaphragm simulated respiratory motion by rhythmic inflation and deflation of 1.5 L water. As biopsy device an 18-gauge prototype biopsy canula with a lancet-like, helically bended cutting edge was used. The artificial lesions were punctured under CT fluoroscopy-guidance (SOMATOM Sensation 64, Siemens, Erlangen, Germany; 30mAs/120 kV/5 mm slice thickness) implementing a dedicated protocol for CT fluoroscopy-guided lung biopsy. The mean-diameter of the artificial lesions was 8.3 {+-} 2.6 mm, and the mean-distance of the phantom wall to the lesions was 54.1 {+-} 13.5 mm. The mean-displacement of the lesions by respiratory motion was 14.1 {+-} 4.0 mm. The mean-duration of CT fluoroscopy was 9.6 {+-} 5.1 s. On a 4-point scale (1 = central; 2 = peripheral; 3 = marginal; 4 = off target), the mean-targeted precision was 1.9 {+-} 0.9. No misplacement of the biopsy canula affecting adjacent structures could be detected. The novel steerable biopsy canula proved to be efficient in the ex-vivo set-up. The chest phantom enabling respiratory motion and the steerable biopsy canula offer a feasible ex-vivo system for evaluating and training CT fluoroscopy-guided lung biopsy adapted to respiratory motion.

  6. Use of 4-Dimensional Computed Tomography-Based Ventilation Imaging to Correlate Lung Dose and Function With Clinical Outcomes

    SciTech Connect

    Vinogradskiy, Yevgeniy; Castillo, Richard; Castillo, Edward; Tucker, Susan L.; Liao, Zhongxing; Guerrero, Thomas; Martel, Mary K.

    2013-06-01

    Purpose: Four-dimensional computed tomography (4DCT)-based ventilation is an emerging imaging modality that can be used in the thoracic treatment planning process. The clinical benefit of using ventilation images in radiation treatment plans remains to be tested. The purpose of the current work was to test the potential benefit of using ventilation in treatment planning by evaluating whether dose to highly ventilated regions of the lung resulted in increased incidence of clinical toxicity. Methods and Materials: Pretreatment 4DCT data were used to compute pretreatment ventilation images for 96 lung cancer patients. Ventilation images were calculated using 4DCT data, deformable image registration, and a density-change based algorithm. Dose–volume and ventilation-based dose function metrics were computed for each patient. The ability of the dose–volume and ventilation-based dose–function metrics to predict for severe (grade 3+) radiation pneumonitis was assessed using logistic regression analysis, area under the curve (AUC) metrics, and bootstrap methods. Results: A specific patient example is presented that demonstrates how incorporating ventilation-based functional information can help separate patients with and without toxicity. The logistic regression significance values were all lower for the dose–function metrics (range P=.093-.250) than for their dose–volume equivalents (range, P=.331-.580). The AUC values were all greater for the dose–function metrics (range, 0.569-0.620) than for their dose–volume equivalents (range, 0.500-0.544). Bootstrap results revealed an improvement in model fit using dose–function metrics compared to dose–volume metrics that approached significance (range, P=.118-.155). Conclusions: To our knowledge, this is the first study that attempts to correlate lung dose and 4DCT ventilation-based function to thoracic toxicity after radiation therapy. Although the results were not significant at the .05 level, our data suggests

  7. Absence of TNF-α enhances inflammatory response in the newborn lung undergoing mechanical ventilation.

    PubMed

    Ehrhardt, Harald; Pritzke, Tina; Oak, Prajakta; Kossert, Melina; Biebach, Luisa; Förster, Kai; Koschlig, Markus; Alvira, Cristina M; Hilgendorff, Anne

    2016-05-15

    Bronchopulmonary dysplasia (BPD), characterized by impaired alveolarization and vascularization in association with lung inflammation and apoptosis, often occurs after mechanical ventilation with oxygen-rich gas (MV-O2). As heightened expression of the proinflammatory cytokine TNF-α has been described in infants with BPD, we hypothesized that absence of TNF-α would reduce pulmonary inflammation, and attenuate structural changes in newborn mice undergoing MV-O2 Neonatal TNF-α null (TNF-α(-/-)) and wild type (TNF-α(+/+)) mice received MV-O2 for 8 h; controls spontaneously breathed 40% O2 Histologic, mRNA, and protein analysis in vivo were complemented by in vitro studies subjecting primary pulmonary myofibroblasts to mechanical stretch. Finally, TNF-α level in tracheal aspirates from preterm infants were determined by ELISA. Although MV-O2 induced larger and fewer alveoli in both, TNF-α(-/-) and TNF-α(+/+) mice, it caused enhanced lung apoptosis (TUNEL, caspase-3/-6/-8), infiltration of macrophages and neutrophils, and proinflammatory mediator expression (IL-1β, CXCL-1, MCP-1) in TNF-α(-/-) mice. These differences were associated with increased pulmonary transforming growth factor-β (TGF-β) signaling, decreased TGF-β inhibitor SMAD-7 expression, and reduced pulmonary NF-κB activity in ventilated TNF-α(-/-) mice. Preterm infants who went on to develop BPD showed significantly lower TNF-α levels at birth. Our results suggest a critical balance between TNF-α and TGF-β signaling in the developing lung, and underscore the critical importance of these key pathways in the pathogenesis of BPD. Future treatment strategies need to weigh the potential benefits of inhibiting pathologic cytokine expression against the potential of altering key developmental pathways. PMID:27016588

  8. Inhibitor of neuronal nitric oxide synthase improves gas exchange in ventilator-induced lung injury after pneumonectomy

    PubMed Central

    2012-01-01

    Background Mechanical ventilation with high tidal volumes may cause ventilator-induced lung injury (VILI) and enhanced generation of nitric oxide (NO). We demonstrated in sheep that pneumonectomy followed by injurious ventilation promotes pulmonary edema. We wished both to test the hypothesis that neuronal NOS (nNOS), which is distributed in airway epithelial and neuronal tissues, could be involved in the pathogenesis of VILI and we also aimed at investigating the influence of an inhibitor of nNOS on the course of VILI after pneumonectomy. Methods Anesthetized sheep underwent right pneumonectomy, mechanical ventilation with tidal volumes (VT) of 6 mL/kg and FiO2 0.5, and were subsequently randomized to a protectively ventilated group (PROTV; n = 8) keeping VT and FiO2 unchanged, respiratory rate (RR) 25 inflations/min and PEEP 4 cm H2O for the following 8 hrs; an injuriously ventilated group with VT of 12 mL/kg, zero end-expiratory pressure, and FiO2 and RR unchanged (INJV; n = 8) and a group, which additionally received the inhibitor of nNOS, 7-nitroindazole (NI) 1.0 mg/kg/h intravenously from 2 hours after the commencement of injurious ventilation (INJV + NI; n = 8). We assessed respiratory, hemodynamic and volumetric variables, including both the extravascular lung water index (EVLWI) and the pulmonary vascular permeability index (PVPI). We measured plasma nitrite/nitrate (NOx) levels and examined lung biopsies for lung injury score (LIS). Results Both the injuriously ventilated groups demonstrated a 2–3-fold rise in EVLWI and PVPI, with no significant effects of NI. In the INJV group, gas exchange deteriorated in parallel with emerging respiratory acidosis, but administration of NI antagonized the derangement of oxygenation and the respiratory acidosis significantly. NOx displayed no significant changes and NI exerted no significant effect on LIS in the INJV group. Conclusion Inhibition of nNOS improved gas exchange, but did not

  9. Lung Motion Model Validation Experiments, Free-Breathing Tissue Densitometry, and Ventilation Mapping using Fast Helical CT Imaging

    NASA Astrophysics Data System (ADS)

    Dou, Hsiang-Tai

    The uncertainties due to respiratory motion present significant challenges to accurate characterization of cancerous tissues both in terms of imaging and treatment. Currently available clinical lung imaging techniques are subject to inferior image quality and incorrect motion estimation, with consequences that can systematically impact the downstream treatment delivery and outcome. The main objective of this thesis is the development of the techniques of fast helical computed tomography (CT) imaging and deformable image registration for the radiotherapy applications in accurate breathing motion modeling, lung tissue density modeling and ventilation imaging. Fast helical CT scanning was performed on 64-slice CT scanner using the shortest available gantry rotation time and largest pitch value such that scanning of the thorax region amounts to just two seconds, which is less than typical breathing cycle in humans. The scanning was conducted under free breathing condition. Any portion of the lung anatomy undergoing such scanning protocol would be irradiated for only a quarter second, effectively removing any motion induced image artifacts. The resulting CT data were pristine volumetric images that record the lung tissue position and density in a fraction of the breathing cycle. Following our developed protocol, multiple fast helical CT scans were acquired to sample the tissue positions in different breathing states. To measure the tissue displacement, deformable image registration was performed that registers the non-reference images to the reference one. In modeling breathing motion, external breathing surrogate signal was recorded synchronously with the CT image slices. This allowed for the tissue-specific displacement to be modeled as parametrization of the recorded breathing signal using the 5D lung motion model. To assess the accuracy of the motion model in describing tissue position change, the model was used to simulate the original high-pitch helical CT scan

  10. Liquid Ventilation

    PubMed Central

    Tawfic, Qutaiba A.; Kausalya, Rajini

    2011-01-01

    Mammals have lungs to breathe air and they have no gills to breath liquids. When the surface tension at the air-liquid interface of the lung increases, as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen, as the inert carrier of oxygen and carbon dioxide offers a number of theoretical advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. The potential for multiple clinical applications for liquid-assisted ventilation will be clarified and optimized in future. PMID:22043370

  11. [Anesthesiological systems "Polinarkon-Vita" with microprocessor for artificial lung ventilation apparatuses and monitoring].

    PubMed

    Trushin, A I; Uliakov, G I; Reĭderman, E N

    2005-01-01

    The anesthesiological systems Polinarkon-Vita for adults and children are described. These systems were developed at VNIIMP-VITA, Ltd. on the basis of basic model of the anesthesiological system Polinarkon-E-Vita. The following new important units of the fifth generation apparatuses for inhalation anesthesia (IA) are described: Anestezist-4 monocomponent evaporator for liquid anesthetics (enfluran and isofluran); Diana, Diana-Det, and Elan-NR apparatuses for mechanical lung ventilation (MLV); dosimeters of medical gases, etc. These systems implement monitoring of vitally important functions of patient and parameters of IN and MLV. The anesthesiological systems Polinarkon-Vita are recommended for medical practice and commercially available from VNIIMP-VITA, Ltd. as small lots.

  12. Chemotherapy for a ventilator-supported patient with small cell lung cancer: A case report

    PubMed Central

    Xiang, Run; Xie, Tianpeng; Li, Qiang

    2016-01-01

    Small cell lung cancer (SCLC) is common in thoracic neoplasms, with a high degree of malignancy and rapid tumor progression. SCLC is often diagnosed with widespread metastases at the time of the initial diagnosis. A small proportion of late-stage SCLC patients are in a poor physical condition and exhibit disqualifying chemoradiotherapy indications. The present study reports the case of a patient who presented with lumbago and backache. Following physical examination, computed tomography, bronchoscopy and biopsy, the patient was diagnosed with SCLC with an Eastern Cooperative Oncology Group score of <2. One cycle of chemotherapy was administered whilst ventilator support was provided, and the patient's condition eventually improved. However, the patient finally succumbed to respiratory failure at 10 months post-diagnosis. PMID:27602149

  13. Noninvasive ventilation for patients with acute lung injury or acute respiratory distress syndrome.

    PubMed

    Nava, Stefano; Schreiber, Ania; Domenighetti, Guido

    2011-10-01

    Few studies have been performed on noninvasive ventilation (NIV) to treat hypoxic acute respiratory failure in patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). The outcomes of these patients, for whom endotracheal intubation is not mandatory, depend on the degree of hypoxia, the presence of comorbidities and complications, and their illness severity. The use of NIV as an alternative to invasive ventilation in severely hypoxemic patients with ARDS (ie, P(aO(2))/F(IO(2)) < 200) is not generally advisable and should be limited to hemodynamically stable patients who can be closely monitored in an intensive care unit by highly skilled staff. Early NIV application may be extremely helpful in immunocompromised patients with pulmonary infiltrates, in whom intubation dramatically increases the risk of infection, pneumonia, and death. The use of NIV in patients with severe acute respiratory syndrome and other airborne diseases has generated debate, despite encouraging clinical results, mainly because of safety issues. Overall, the high rate of NIV failure suggests a cautious approach to NIV use in patients with ALI/ARDS, including early initiation, intensive monitoring, and prompt intubation if signs of NIV failure emerge. PMID:22008399

  14. A novel method for right one-lung ventilation modeling in rabbits

    PubMed Central

    Xu, Ze-Ping; Gu, Lian-Bing; Bian, Qing-Ming; Li, Peng-Yi; Wang, Li-Jun; Chen, Xiao-Xiang; Zhang, Jing-Yuan

    2016-01-01

    There is no standard method by which to establish a right one-lung ventilation (OLV) model in rabbits. In the present study, a novel method is proposed to compare with two other methods. After 0.5 h of baseline two-lung ventilation (TLV), 40 rabbits were randomly divided into sham group (TLV for 3 h as a contrast) and three right-OLV groups (right OLV for 3 h with different methods): Deep intubation group, clamp group and blocker group (deeply intubate the self-made bronchial blocker into the left main bronchus, the novel method). These three methods were compared using a number of variables: Circulation by heart rate (HR), mean arterial pressure (MAP); oxygenation by arterial blood gas analysis; airway pressure; lung injury by histopathology; and time, blood loss, success rate of modeling. Following OLV, compared with the sham group, arterial partial pressure of oxygen and arterial hemoglobin oxygen saturation decreased, peak pressure increased and lung injury scores were higher in three OLV groups at 3 h of OLV. All these indexes showed no differences between the three OLV groups. During right-OLV modeling, less time was spent in the blocker group (6±2 min), compared with the other two OLV groups (13±4 min in deep intubation group, P<0.05; 33±9 min in clamp group, P<0.001); more blood loss was observed in clamp group (11.7±2.8 ml), compared with the other two OLV groups (2.3±0.5 ml in deep intubation group, P<0.001; 2.1±0.6 ml in blocker group, P<0.001). The first-time and final success rate of modeling showed no differences among the three OLV groups. Deep intubation of the self-made bronchial blocker into the left main bronchus is an easy, effective and reliable method to establish a right-OLV model in rabbits. PMID:27446346

  15. Echocardiographic evaluation of pulmonary venous blood flow and cardiac function changes during one-lung ventilation

    PubMed Central

    Lee, Su Hyun; Kim, Namo; Kim, Hyun IL; Oh, Young Jun

    2015-01-01

    Objectives: The intra-pulmonary shunt induced by one-lung ventilation (OLV), is alleviated by increased pulmonary blood flow by gravitational redistribution and hypoxic pulmonary vasoconstriction. We investigated the changes of pulmonary venous blood flow (PVBF) and biventricular function during OLV with echocardiography. And the correlation between PVBF and intra-pulmonary shunt fraction (Qs/Qt) was evaluated. Methods: PVBF of the left upper pulmonary vein and cardiac function were measured with echocardiography in twenty-five patients who underwent elective thoracic surgery in left lateral decubitus. Qs/Qt and PaO2 were measured with blood gas analysis. Data was obtained at 10 min after two-lung ventilation in supine (TLV-S) and lateral decubitus position (TLV-L), and at 10, 20 and 30 min after OLV in lateral decubitus position (OLV-10, -20 and -30). Results: There were significant changes in PVBF among TLV-S, TLV-L and OLV-10 (959.5±280.8, 1416.9±489.7 and 1999.9±670.5 ml/min; P<0.05, respectively). There were not differences in PVBF, Qs/Qt and PaO2 among OLV-10, -20 and -30. There were an inverse correlation between percent change of PVBF and change of Qs/Qt (r2 = 0.5; P<0.0001) and positive correlations between the percent change of PVBF and change of PaO2 (r2 = 0.4; P<0.0001) during OLV over TLV-L. No significant changes in biventricular systolic and diastolic function were observed during positional change and OLV. Conclusions: A remarkable change of PVBF relevant to gravitational distribution and hypoxic pulmonary vasoconstriction was proved by echocardiography. And PVBF changes could represent the changes of Qs/Qt and PaO2 during OLV. However, biventricular function was not impaired during OLV. PMID:26550232

  16. Mechanical ventilator - infants

    MedlinePlus

    ... gas measurements, and x-rays. WHAT ARE THE RISKS OF A MECHANICAL VENTILATOR? Most babies who need ventilator assistance have some lung problems, including immature or diseased lungs, which are ... for injury. Sometimes, delivering oxygen under pressure can ...

  17. Assessment of regional lung ventilation by electrical impedance tomography in a patient with unilateral bronchial stenosis and a history of tuberculosis*

    PubMed Central

    Marinho, Liégina Silveira; de Sousa, Nathalia Parente; Barros, Carlos Augusto Barbosa da Silveira; Matias, Marcelo Silveira; Monteiro, Luana Torres; Beraldo, Marcelo do Amaral; Costa, Eduardo Leite Vieira; Amato, Marcelo Britto Passos; Holanda, Marcelo Alcantara

    2013-01-01

    Bronchial stenosis can impair regional lung ventilation by causing abnormal, asymmetric airflow limitation. Electrical impedance tomography (EIT) is an imaging technique that allows the assessment of regional lung ventilation and therefore complements the functional assessment of the lungs. We report the case of a patient with left unilateral bronchial stenosis and a history of tuberculosis, in whom regional lung ventilation was assessed by EIT. The EIT results were compared with those obtained by ventilation/perfusion radionuclide imaging. The patient was using nasal continuous positive airway pressure (CPAP) for the treatment of obstructive sleep apnea syndrome. Therefore, we studied the effects of postural changes and of the use of nasal CPAP. The EIT revealed heterogeneous distribution of regional lung ventilation, the ventilation being higher in the right lung, and this distribution was influenced by postural changes and CPAP use. The EIT assessment of regional lung ventilation produced results similar to those obtained with the radionuclide imaging technique and had the advantage of providing a dynamic evaluation without radiation exposure. PMID:24473768

  18. Lung Motion Model Validation Experiments, Free-Breathing Tissue Densitometry, and Ventilation Mapping using Fast Helical CT Imaging

    NASA Astrophysics Data System (ADS)

    Dou, Hsiang-Tai

    The uncertainties due to respiratory motion present significant challenges to accurate characterization of cancerous tissues both in terms of imaging and treatment. Currently available clinical lung imaging techniques are subject to inferior image quality and incorrect motion estimation, with consequences that can systematically impact the downstream treatment delivery and outcome. The main objective of this thesis is the development of the techniques of fast helical computed tomography (CT) imaging and deformable image registration for the radiotherapy applications in accurate breathing motion modeling, lung tissue density modeling and ventilation imaging. Fast helical CT scanning was performed on 64-slice CT scanner using the shortest available gantry rotation time and largest pitch value such that scanning of the thorax region amounts to just two seconds, which is less than typical breathing cycle in humans. The scanning was conducted under free breathing condition. Any portion of the lung anatomy undergoing such scanning protocol would be irradiated for only a quarter second, effectively removing any motion induced image artifacts. The resulting CT data were pristine volumetric images that record the lung tissue position and density in a fraction of the breathing cycle. Following our developed protocol, multiple fast helical CT scans were acquired to sample the tissue positions in different breathing states. To measure the tissue displacement, deformable image registration was performed that registers the non-reference images to the reference one. In modeling breathing motion, external breathing surrogate signal was recorded synchronously with the CT image slices. This allowed for the tissue-specific displacement to be modeled as parametrization of the recorded breathing signal using the 5D lung motion model. To assess the accuracy of the motion model in describing tissue position change, the model was used to simulate the original high-pitch helical CT scan

  19. Common-path Fourier domain optical coherence tomography of irradiated human skin and ventilated isolated rabbit lungs

    NASA Astrophysics Data System (ADS)

    Popp, A.; Wendel, M.; Knels, L.; Knuschke, P.; Mehner, M.; Koch, T.; Boller, D.; Koch, P.; Koch, E.

    2005-08-01

    A compact common path Fourier domain optical coherence tomography (FD-OCT) system based on a broadband superluminescence diode is used for biomedical imaging. The epidermal thickening of human skin after exposure to ultraviolet radiation is measured to proof the feasibility of FD-OCT for future substitution of invasive biopsies in a long term study on natural UV skin protection. The FD-OCT system is also used for imaging lung parenchyma. FD-OCT images of a formalin fixated lung show the same alveolar structure as scanning electron microscopy images. In the ventilated and blood-free perfused isolated rabbit lung FD-OCT is used for real-time cross-sectional image capture of alveolar mechanics throughout tidal ventilation. The alveolar mechanics changing from alternating recruitment-derecruitment at zero positive end-expiratory pressure (PEEP) to persistent recruitment after applying a PEEP of 5 cm H2O is observed in the OCT images.

  20. VEGF Production by Ly6C+high Monocytes Contributes to Ventilator-Induced Lung Injury

    PubMed Central

    Lin, Chin-Kuo; Li, Jhy-Ming; Chen, Mei-Hsin; Tsai, Mei-Ling; Chang, Chih-Ching

    2016-01-01

    Background Mechanical ventilation is a life-saving procedure for patients with acute respiratory failure, although it may cause pulmonary vascular inflammation and leakage, leading to ventilator-induced lung injury (VILI). Ly6C+high monocytes are involved in the pathogenesis of VILI. In this study, we investigated whether pulmonary infiltrated Ly6C+high monocytes produce vascular endothelial growth factor (VEGF) and contribute to VILI. Methods A clinically relevant two-hit mouse model of VILI, with intravenous lipopolysaccharide (LPS, 20 ng/mouse) immediately before high tidal volume (HTV, 20 mL/kg) ventilation (LPS+HTV), was established. Blood gas and respiratory mechanics were measured to ensure the development of VILI. Flow cytometry and histopathological analyses revealed pulmonary infiltration of leukocytes subsets. Clodronate liposomes were intravenously injected to deplete pulmonary monocytes. In vitro endothelial cell permeability assay with sorted Ly6C+high monocytes condition media assessed the role of Ly6C+high monocytes in vascular permeability. Results LPS+HTV significantly increased total proteins, TNF-α, IL-6, vascular endothelial growth factor (VEGF) and mononuclear cells in the bronchoalveolar lavage fluid (BALF). Pulmonary Ly6C+high monocytes (SSClowCD11b+F4/80+Ly6C+high), but not Ly6C+low monocytes (SSClowCD11b+F4/80+Ly6C+low), were significantly elevated starting at 4 hr. Clodronate liposomes were able to significantly reduce pulmonary Ly6C+high monocytes, and VEGF and total protein in BALF, and restore PaO2/FiO2. There was a strong correlation between pulmonary Ly6C+high monocytes and BALF VEGF (R2 = 0.8791, p<0.001). Moreover, sorted Ly6C+high monocytes were able to produce VEGF, resulting in an increased permeability of endothelial cell monolayer in an in vitro endothelial cell permeability assay. Conclusion VEGF produced by pulmonary infiltrated Ly6C+high monocytes regulates vasculature permeability in a two-hit model of HTV-induced lung

  1. Pre-Treatment with Allopurinol or Uricase Attenuates Barrier Dysfunction but Not Inflammation during Murine Ventilator-Induced Lung Injury

    PubMed Central

    Kuipers, Maria T.; Aslami, Hamid; Vlaar, Alexander P. J.; Juffermans, Nicole P.; Tuip-de Boer, Anita M.; Hegeman, Maria A.; Jongsma, Geartsje; Roelofs, Joris J. T. H.; van der Poll, Tom; Schultz, Marcus J.; Wieland, Catharina W.

    2012-01-01

    Introduction Uric acid released from injured tissue is considered a major endogenous danger signal and local instillation of uric acid crystals induces acute lung inflammation via activation of the NLRP3 inflammasome. Ventilator-induced lung injury (VILI) is mediated by the NLRP3 inflammasome and increased uric acid levels in lung lavage fluid are reported. We studied levels in human lung injury and the contribution of uric acid in experimental VILI. Methods Uric acid levels in lung lavage fluid of patients with acute lung injury (ALI) were determined. In a different cohort of cardiac surgery patients, uric acid levels were correlated with pulmonary leakage index. In a mouse model of VILI the effect of allopurinol (inhibits uric acid synthesis) and uricase (degrades uric acid) pre-treatment on neutrophil influx, up-regulation of adhesion molecules, pulmonary and systemic cytokine levels, lung pathology, and regulation of receptors involved in the recognition of uric acid was studied. In addition, total protein and immunoglobulin M in lung lavage fluid and pulmonary wet/dry ratios were measured as markers of alveolar barrier dysfunction. Results Uric acid levels increased in ALI patients. In cardiac surgery patients, elevated levels correlated significantly with the pulmonary leakage index. Allopurinol or uricase treatment did not reduce ventilator-induced inflammation, IκB-α degradation, or up-regulation of NLRP3, Toll-like receptor 2, and Toll-like receptor 4 gene expression in mice. Alveolar barrier dysfunction was attenuated which was most pronounced in mice pre-treated with allopurinol: both treatment strategies reduced wet/dry ratio, allopurinol also lowered total protein and immunoglobulin M levels. Conclusions Local uric acid levels increase in patients with ALI. In mice, allopurinol and uricase attenuate ventilator-induced alveolar barrier dysfunction. PMID:23226314

  2. 4-D segmentation and normalization of 3He MR images for intrasubject assessment of ventilated lung volumes

    NASA Astrophysics Data System (ADS)

    Contrella, Benjamin; Tustison, Nicholas J.; Altes, Talissa A.; Avants, Brian B.; Mugler, John P., III; de Lange, Eduard E.

    2012-03-01

    Although 3He MRI permits compelling visualization of the pulmonary air spaces, quantitation of absolute ventilation is difficult due to confounds such as field inhomogeneity and relative intensity differences between image acquisition; the latter complicating longitudinal investigations of ventilation variation with respiratory alterations. To address these potential difficulties, we present a 4-D segmentation and normalization approach for intra-subject quantitative analysis of lung hyperpolarized 3He MRI. After normalization, which combines bias correction and relative intensity scaling between longitudinal data, partitioning of the lung volume time series is performed by iterating between modeling of the combined intensity histogram as a Gaussian mixture model and modulating the spatial heterogeneity tissue class assignments through Markov random field modeling. Evaluation of the algorithm was retrospectively applied to a cohort of 10 asthmatics between 19-25 years old in which spirometry and 3He MR ventilation images were acquired both before and after respiratory exacerbation by a bronchoconstricting agent (methacholine). Acquisition was repeated under the same conditions from 7 to 467 days (mean +/- standard deviation: 185 +/- 37.2) later. Several techniques were evaluated for matching intensities between the pre and post-methacholine images with the 95th percentile value histogram matching demonstrating superior correlations with spirometry measures. Subsequent analysis evaluated segmentation parameters for assessing ventilation change in this cohort. Current findings also support previous research that areas of poor ventilation in response to bronchoconstriction are relatively consistent over time.

  3. Strip sign: a new sign for diagnosis of nonembolic defects on pulmonary perfusion scintigraphy

    SciTech Connect

    Sostman, H.D.; Gottschalk, A.

    1982-03-01

    A total of 47 patients who underwent both lung ventilation-perfusion scintigraphy and pulmonary arteriography were evaluated for presence on the scintigram of perfusion defects that did not extend to the lung edge, leaving a peripheral parenchymal stripe (PPS) of perfused lung between the defect and the adjacent pleural surface. Scans were scored both with and without regard for the PPS according to probability of pulmonary embolism; these predictions were then compared with the official lung scan report given initially to the referring physician. Predictions were then verified by pulmonary arteriography. Of the 13 patients who showed one or more PPSs, four reports would have been more accurate using the revised criteria that included the stripe sign. In this study, visualization of a PPS in an area of defect on a perfusion lung scan was extremely accurate for predicting absence of pulmonary emboli in the specific area of the stripe. Further studies that would be needed to confirm this finding are discussed.

  4. Mild hypothermia attenuates changes in respiratory system mechanics and modifies cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation.

    PubMed

    Dostál, P; Senkeřík, M; Pařízková, R; Bareš, D; Zivný, P; Zivná, H; Cerný, V

    2010-01-01

    Hypothermia was shown to attenuate ventilator-induced lung injury due to large tidal volumes. It is unclear if the protective effect of hypothermia is maintained under less injurious mechanical ventilation in animals without previous lung injury. Tracheostomized rats were randomly allocated to non-ventilated group (group C) or ventilated groups of normothermia (group N) and mild hypothermia (group H). After two hours of mechanical ventilation with inspiratory fraction of oxygen 1.0, respiratory rate 60 min(-1), tidal volume 10 ml x kg(-1), positive end-expiratory pressure (PEEP) 2 cm H2O or immediately after tracheostomy in non-ventilated animals inspiratory pressures were recorded, rats were sacrificed, pressure-volume (PV) curve of respiratory system constructed, bronchoalveolar lavage (BAL) fluid and aortic blood samples obtained. Group N animals exhibited a higher rise in peak inspiratory pressures in comparison to group H animals. Shift of the PV curve to right, higher total protein and interleukin-6 levels in BAL fluid were observed in normothermia animals in comparison with hypothermia animals and non-ventilated controls. Tumor necrosis factor-alpha was lower in the hypothermia group in comparison with normothermia and non-ventilated groups. Mild hypothermia attenuated changes in respiratory system mechanics and modified cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation in animals without previous lung injury.

  5. (68)Ga PET Ventilation and Perfusion Lung Imaging-Current Status and Future Challenges.

    PubMed

    Bailey, Dale L; Eslick, Enid M; Schembri, Geoffrey P; Roach, Paul J

    2016-09-01

    Gallium-68 ((68)Ga) is a positron-emitting radionuclide suitable for positron emission tomography (PET) imaging that has a number of convenient features-it has a physical half life of 68 minutes, it is generator produced at the PET facility and needs no local cyclotron, and being a radiometal is able to be chelated to a number of useful molecules for diagnostic imaging with PET. (68)Ga has recently been investigated as a radiotracer for ventilation and perfusion (V/Q) lung imaging. It is relatively easy to produce both V/Q radiopharmaceuticals labeled with (68)Ga for PET studies, it offers higher spatial resolution than equivalent SPECT studies, the short half life allows for multiple (repeated) scans on the same day, and low amounts of radiotracer can be used thus limiting the radiation dose to the subject. In the usual clinical setting requiring a V/Q scan, that of suspected pulmonary embolism, the role of (68)Ga V/Q PET may be limited from a logistical perspective, however, in nonacute applications such as lung function evaluation, radiotherapy treatment planning, and respiratory physiology investigations it would appear to be an ideal modality to employ. PMID:27553468

  6. Albuterol delivery in a neonatal ventilated lung model: Nebulization versus chlorofluorocarbon- and hydrofluoroalkane-pressurized metered dose inhalers.

    PubMed

    Lugo, R A; Kenney, J K; Keenan, J; Salyer, J W; Ballard, J; Ward, R M

    2001-03-01

    The aim of this study was to compare albuterol delivery in a neonatal ventilated lung model, using three delivery methods: 1) jet nebulizer; 2) chlorofluorocarbon-pressurized metered dose inhaler (CFC-MDI) actuated into an ACE(R) spacer; and 3) hydrofluoroalkane-pressurized MDI (HFA-MDI) actuated into an ACE(R) spacer. The bench model consisted of a mechanically ventilated infant test lung with ventilator settings to simulate a very low birth weight neonate with moderate lung disease. Albuterol solution (0.5%) was nebulized at the humidifier and temperature port, 125 cm and 30 cm from the Y-piece, respectively. Albuterol metered dose inhalers (MDIs) were actuated into an ACE(R) spacer that was tested in two positions: 1) inline between the endotracheal (ET) tube and the Y-piece; and 2) attached to the ET tube and administered by manual ventilation. Albuterol was collected on a filter at the distal end of the ET tube and was quantitatively analyzed by high performance liquid chromatography. Albuterol delivery by CFC-MDI (position 1, 4.8 +/- 1.0%, vs. position 2, 3.8 +/- 1.6%, P > 0.05) and HFA-MDI (position 1, 5.7 +/- 1.6%, vs. position 2, 5.5 +/- 2.4%, P > 0.05) were significantly greater than delivery by nebulization at 30 cm (0.16 +/- 0.07%) and 125 cm (0.15 +/- 0.03%) from the Y-piece (P < 0.001). A single actuation of albuterol MDI delivered the equivalent of nebulizing 2.5-3.7 mg of albuterol solution. We conclude that albuterol administered by MDI and ACE(R) spacer resulted in more efficient delivery than by nebulization in this mechanically ventilated neonatal lung model. There was no significant difference in drug delivery between CFC-MDI and HFA-MDI; nor did the placement of the spacer significantly affect drug delivery.

  7. Successful single-lung ventilation using a bronchial occluder for repair a large tracheoesophageal fistula: a case report

    PubMed Central

    Zhang, Lele; Zhao, Xiang; Li, Quan

    2015-01-01

    A 25-year-old girl was found a large tracheoesophageal fistula (TEF) 20 cm away from the incisors by gastroscope. It was a consequence of prolong intubation after the head operation because of right temporal lobe cerebral hemorrhage broken into ventricles. The patient was tracheotomy and retained spontaneous breathing. Operation was planned to via cervical and thoracic abdominal esophageal transection plus cervical esophagogastrostomy to repair the fistula under single lung ventilation under general anesthesia. Here we report a successful case using an endotracheal tube (EET) combine with a bronchial occluder for single ventilation to repair a large TEF. PMID:26550434

  8. Acid rain: effects on arachidonic acid metabolism in perfused and ventilated guinea-pig lung.

    PubMed

    Preziosi, P; Ciabattoni, G

    1987-11-01

    Isolated, perfused and ventilated guinea-pig lungs were exposed for 10 min to acid (sulphuric + nitric acid) aerosol mimicking acid rain at pH 4.5 or 2.5, as well as to a control distilled water aerosol (pH 6.0-6.5). Lung perfusing solution was recovered and thromboxane (TX) B2 and leukotriene (LT) B4 were measured by radioimmunoassay (RIA) techniques. In a series of experiments TXB2 release averaged 0.43 +/- 0.18 (+/- SD) ng/min during exposure to distilled water aerosol and increased to 0.70 +/- 0.30 ng/min during exposure to acid aerosol at pH 4.5 (P less than 0.05). In a second series of experiments TXB2 release was 0.46 +/- 0.18 ng/min and increased to 1.07 +/- 0.51 ng/min (P less than 0.01) after acid aerosol at pH 2.5. In both cases LTB4 release, reflecting lipoxygenase activity, was unchanged. LTC4 levels were not measurable under basal conditions as well as after exposure to acid aerosol. A pneumoconstriction was also observed, being more pronounced after acid aerosol at pH 2.5. Individual sulphuric and nitric acid aerosol component solutions at pH 2.5 evoked TXB2 and airway resistance changes corresponding to those observed with the mixed acid aerosol. LTB4 was not modified. Acid rain inhalation may directly stimulate pathways leading to the bronchoconstrictor and pro-aggregating TXA2 synthesis in isolated guinea-pig lung, without affecting the lipoxygenase pathway of arachidonic acid metabolism.

  9. Customization of an open-lung ventilation strategy to treat a case of life-threatening acute respiratory distress syndrome.

    PubMed

    Grooms, David A; Sibole, Stephen H; Tomlinson, James R; Marik, Paul E; Chatburn, Robert L

    2011-04-01

    The ARDS Network low-tidal-volume protocol is considered the standard of care for patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). The protocol is built on the foundation of low-tidal-volume ventilation, use of a combined PEEP and F(IO(2)) table, and managing alveolar end-inspiratory pressure by limiting the plateau airway pressure to ≤ 30 cm H(2)O. Although this strategy, to date, is the only method that significantly improves ALI/ARDS survival, alternative methods of improving hypoxemia and minimizing ventilator-induced lung injury, in conjunction with low-tidal-volume ventilation, can be used for life-threatening ARDS. We present a case in which we customized the use of alveolar recruitment maneuvers by analyzing the hysteresis of the pressure-volume curve to assess lung recruitability, decremental PEEP to sustain lung recruitment, and careful use of plateau pressure ≥ 30 cm H(2)O, which improved our patient's life-threatening hypoxemia within the first 36 min of arrival to our ICU.

  10. Pulmonary microRNA profiling in a mouse model of ventilator-induced lung injury

    PubMed Central

    Vergadi, Eleni; Kaniaris, Evangelos; Hatziapostolou, Maria; Lagoudaki, Eleni; Georgopoulos, Dimitrios; Zapol, Warren M.; Bloch, Kenneth D.; Iliopoulos, Dimitris

    2012-01-01

    The aim of this study was to investigate the changes induced by high tidal volume ventilation (HVTV) in pulmonary expression of micro-RNAs (miRNAs) and identify potential target genes and corresponding miRNA-gene networks. Using a real-time RT-PCR-based array in RNA samples from lungs of mice subjected to HVTV for 1 or 4 h and control mice, we identified 65 miRNAs whose expression changed more than twofold upon HVTV. An inflammatory and a TGF-β-signaling miRNA-gene network were identified by in silico pathway analysis being at highest statistical significance (P = 10−43 and P = 10−28, respectively). In the inflammatory network, IL-6 and SOCS-1, regulated by miRNAs let-7 and miR-155, respectively, appeared as central nodes. In TGF-β-signaling network, SMAD-4, regulated by miR-146, appeared as a central node. The contribution of miRNAs to the development of lung injury was evaluated in mice subjected to HVTV treated with a precursor or antagonist of miR-21, a miRNA highly upregulated by HVTV. Lung compliance was preserved only in mice treated with anti-miR-21 but not in mice treated with pre-miR-21 or negative-control miRNA. Both alveolar-arterial oxygen difference and protein levels in bronchoalveolar lavage were lower in mice treated with anti-miR-21 than in mice treated with pre-miR-21 or negative-control miRNA (DA-a: 66 ± 27 vs. 131 ± 22, 144 ± 10 mmHg, respectively, P < 0.001; protein concentration: 1.1 ± 0.2 vs. 2.3 ± 1, 2.1 ± 0.4 mg/ml, respectively, P < 0.01). Our results show that HVTV induces changes in miRNA expression in mouse lungs. Modulation of miRNA expression can affect the development of HVTV-induced lung injury. PMID:22659882

  11. Prolonged Mechanical Ventilation After Lung Transplantation-A Single-Center Study.

    PubMed

    Hadem, J; Gottlieb, J; Seifert, D; Fegbeutel, C; Sommer, W; Greer, M; Wiesner, O; Kielstein, J T; Schneider, A S; Ius, F; Fuge, J; Kühn, C; Tudorache, I; Haverich, A; Welte, T; Warnecke, G; Hoeper, M M

    2016-05-01

    This single-center study examines the incidence, etiology, and outcomes associated with prolonged mechanical ventilation (PMV), defined as time to definite spontaneous ventilation >21 days after double lung transplantation (LTx). A total of 690 LTx recipients between January 2005 and December 2012 were analyzed. PMV was necessary in 95 (13.8%) patients with decreasing incidence during the observation period (p < 0.001). Independent predictors of PMV were renal replacement therapy (odds ratio [OR] 11.13 [95% CI, 5.82-21.29], p < 0.001), anastomotic dehiscence (OR 8.74 [95% CI 2.42-31.58], p = 0.001), autoimmune comorbidity (OR 5.52 [95% CI 1.86-16.41], p = 0.002), and postoperative neurologic complications (OR 5.03 [95% CI 1.98-12.81], p = 0.001), among others. Overall 1-year survival was 86.0% (90.4% for LTx between 2010 and 2012); it was 60.7% after PMV and 90.0% in controls (p < 0.001). Conditional long-term outcome among hospital survivors, however, did not differ between the groups (p = 0.78). Multivariate analysis identified renal replacement therapy (hazard ratio [HR] 3.55 [95% CI 2.40-5.25], p < 0.001), post-LTx extracorporeal membrane oxygenation (HR 3.47 [95% CI 2.06-5.83], p < 0.001), and prolonged inotropic support (HR 1.95 [95% CI 1.39-2.75], p < 0.001), among others, as independent predictors of mortality. In conclusion, PMV complicated 14% of LTx procedures and, although associated with increased in-hospital mortality, outcomes among patients surviving to hospital discharge were unaffected. PMID:26607844

  12. The effect of low level laser therapy on ventilator-induced lung injury in mice (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Szabari, Margit V.; Miller, Alyssa J.; Hariri, Lida P.; Hamblin, Michael R.; Musch, Guido; Stroh, Helene; Suter, Melissa J.

    2016-03-01

    Although mechanical ventilation (MV) is necessary to support gas exchange in critically ill patients, it can contribute to the development of lung injury and multiple organ dysfunction. It is known that high tidal volume (Vt) MV can cause ventilator-induced lung injury (VILI) in healthy lungs and increase the mortality of patients with Acute Respiratory Distress Syndrome. Low level laser therapy (LLLT) has demonstrated to have anti-inflammatory effects. We investigated whether LLLT could alleviate inflammation from injurious MV in mice. Adult mice were assigned to 2 groups: VILI+LLLT group (3 h of injurious MV: Vt=25-30 ml/kg, respiratory rate (RR)=50/min, positive end-expiratory pressure (PEEP)=0 cmH20, followed by 3 h of protective MV: Vt=9 ml/kg, RR=140/min, PEEP=2 cmH20) and VILI+no LLLT group. LLLT was applied during the first 30 min of the MV (810 nm LED system, 5 J/cm2, 1 cm above the chest). Respiratory impedance was measured in vivo with forced oscillation technique and lung mechanics were calculated by fitting the constant phase model. At the end of the MV, bronchoalveolar lavage (BAL) was performed and inflammatory cells counted. Lungs were removed en-bloc and fixed for histological evaluation. We hypothesize that LLLT can reduce lung injury and inflammation from VILI. This therapy could be translated into clinical practice, where it can potentially improve outcomes in patients requiring mechanical ventilation in the operating room or in the intensive care units.

  13. Visualization of neonatal lung injury associated with mechanical ventilation using x-ray dark-field radiography

    NASA Astrophysics Data System (ADS)

    Yaroshenko, Andre; Pritzke, Tina; Koschlig, Markus; Kamgari, Nona; Willer, Konstantin; Gromann, Lukas; Auweter, Sigrid; Hellbach, Katharina; Reiser, Maximilian; Eickelberg, Oliver; Pfeiffer, Franz; Hilgendorff, Anne

    2016-04-01

    Mechanical ventilation (MV) and supplementation of oxygen-enriched gas, often needed in postnatal resuscitation procedures, are known to be main risk factors for impaired pulmonary development in the preterm and term neonates. Unfortunately, current imaging modalities lack in sensitivity for the detection of early stage lung injury. The present study reports a new imaging approach for diagnosis and staging of early lung injury induced by MV and hyperoxia in neonatal mice. The imaging method is based on the Talbot-Lau x-ray grating interferometry that makes it possible to quantify the x-ray small-angle scattering on the air-tissue interfaces. This so-called dark-field signal revealed increasing loss of x-ray small-angle scattering when comparing images of neonatal mice undergoing hyperoxia and MV-O2 with animals kept at room air. The changes in the dark field correlated well with histologic findings and provided superior differentiation than conventional x-ray imaging and lung function testing. The results suggest that x-ray dark-field radiography is a sensitive tool for assessing structural changes in the developing lung. In the future, with further technical developments x-ray dark-field imaging could be an important tool for earlier diagnosis and sensitive monitoring of lung injury in neonates requiring postnatal oxygen or ventilator therapy.

  14. Visualization of neonatal lung injury associated with mechanical ventilation using x-ray dark-field radiography

    PubMed Central

    Yaroshenko, Andre; Pritzke, Tina; Koschlig, Markus; Kamgari, Nona; Willer, Konstantin; Gromann, Lukas; Auweter, Sigrid; Hellbach, Katharina; Reiser, Maximilian; Eickelberg, Oliver; Pfeiffer, Franz; Hilgendorff, Anne

    2016-01-01

    Mechanical ventilation (MV) and supplementation of oxygen-enriched gas, often needed in postnatal resuscitation procedures, are known to be main risk factors for impaired pulmonary development in the preterm and term neonates. Unfortunately, current imaging modalities lack in sensitivity for the detection of early stage lung injury. The present study reports a new imaging approach for diagnosis and staging of early lung injury induced by MV and hyperoxia in neonatal mice. The imaging method is based on the Talbot-Lau x-ray grating interferometry that makes it possible to quantify the x-ray small-angle scattering on the air-tissue interfaces. This so-called dark-field signal revealed increasing loss of x-ray small-angle scattering when comparing images of neonatal mice undergoing hyperoxia and MV-O2 with animals kept at room air. The changes in the dark field correlated well with histologic findings and provided superior differentiation than conventional x-ray imaging and lung function testing. The results suggest that x-ray dark-field radiography is a sensitive tool for assessing structural changes in the developing lung. In the future, with further technical developments x-ray dark-field imaging could be an important tool for earlier diagnosis and sensitive monitoring of lung injury in neonates requiring postnatal oxygen or ventilator therapy. PMID:27072871

  15. [Dexmedetomidine suppresses the expressions of TLR4, NF-κB and ICAM-1 mRNA in the lung of rabbits during one lung ventilation].

    PubMed

    Bian, Qingming; Gu, Lianbing; Xu, Zeping; Li, Pengyi; Qian, Yanning; Zhu, Dongya

    2016-09-01

    Objective To investigate the effect of dexmedetomidine on lung injury and the expressions of Toll-like receptor 4 (TLR4), nuclear factor κB p65 (NF-κB p65) and intercellular adhesion molecular 1 (ICAM-1) mRNA during one-lung ventilation (OLV) in rabbits. Methods Thirty healthy New Zealand white rabbits were randomly divided into three groups ( n=10 in each group): two-lung ventilation (TLV) group (group T), OLV group (group O), dexmedetomidine used during OLV group (group D-O). The rabbits in group T were treated with TLV for 3.5 hours, while in group O and group D-O, the rabbits were ventilated through right lung for 3 hours following 30-minute TLV. In group D-O, dexmedetomidine (1 μg/kg) were given intravenously for 10 minutes before tracheostomy, followed by intravenous infusion at the rate of 1 μg/(kg.h). Equal volume of normal saline was given in group O and group T as controls. At the end of the experiment, rabbits were sacrificed and lung tissues were collected. The pulmonary wet/dry mass (W/D) ratio was calculated and the pathological changes of the lungs were observed using HE staining under a light microscope. The expressions of TLR4, NF-κB p65, ICAM-1 mRNA were analyzed by real-time quantitative PCR. Results W/D ratio of left lung tissues in group O and group D-O were significantly higher as compared with group T. However, W/D ratio in group D-O was obviously lower than that in group O. Compared with group T, both group O and group D-O showed much more serious morphological damage in the lung, and such lung injury was less obvious in group D-O than in group O. The expressions of TLR4, NF-κB p65, ICAM-1 mRNA increased significantly in group O as compared with group T, and such enhancement was ameliorated by dexmedetomidine as observed in group D-O. Conclusion Dexmedetomidine might inhibit inflammatory responses and attenuate OLV-induced lung injury in rabbits, possibly by suppressing the expressions of TLR4 and NF-κB p65 mRNA. PMID:27609575

  16. SU-E-J-149: Establishing the Relationship Between Pre-Treatment Lung Ventilation, Dose, and Toxicity Outcome

    SciTech Connect

    Mistry, N; D'Souza, W; Sornsen de Koste, J; Senan, S

    2014-06-01

    Purpose: Recently, there has been an interest in incorporating functional information in treatment planning especially in thoracic tumors. The rationale is that healthy lung regions need to be spared from radiation if possible to help achieve better control on toxicity. However, it is still unclear whether high functioning regions need to be spared or have more capacity to deal with the excessive radiation as compared to the compromised regions of the lung. Our goal with this work is to establish the tools by which we can establish a relationship between pre-treatment lung function, dose, and radiographic outcomes of lung toxicity. Methods: Treatment planning was performed using a single phase of a 4DCT scan, and follow-up anatomical CT scans were performed every 3 months for most patients. In this study, we developed the pipeline of tools needed to analyze such a large dataset, while trying to establish a relationship between function, dose, and outcome. Pre-treatment lung function was evaluated using a recently published technique that evaluates Fractional Regional Ventilation (FRV). All images including the FRV map and the individual follow-up anatomical CT images were all spatially matched to the planning CT using a diffusion based Demons image registration algorithm. Change in HU value was used as a metric to capture the effects of lung toxicity. To validate the findings, a radiologist evaluated the follow-up anatomical CT images and scored lung toxicity. Results: Initial experience in 1 patient shows a relationship between the pre-treatment lung function, dose and toxicity outcome. The results are also correlated to the findings by the radiologist who was blinded to the analysis or dose. Conclusion: The pipeline we have established to study this enables future studies in large retrospective studies. However, the tools are dependent on the fidelity of 4DCT reconstruction for accurate evaluation of regional ventilation. Patent Pending for the technique

  17. Liquid ventilation

    PubMed Central

    Sarkar, Suman; Paswan, Anil; Prakas, S.

    2014-01-01

    Human have lungs to breathe air and they have no gills to breath liquids like fish. When the surface tension at the air-liquid interface of the lung increases as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen as the inert carrier of oxygen and carbon dioxide offers a number of advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. It is well-known that respiratory diseases are one of the most common causes of morbidity and mortality in intensive care unit. During the past few years several new modalities of treatment have been introduced. One of them and probably the most fascinating, is of LV. Partial LV, on which much of the existing research has concentrated, requires partial filling of lungs with perfluorocarbons (PFC's) and ventilation with gas tidal volumes using conventional mechanical ventilators. Various physico-chemical properties of PFC's make them the ideal media. It results in a dramatic improvement in lung compliance and oxygenation and decline in mean airway pressure and oxygen requirements. No long-term side-effect reported. PMID:25886321

  18. Validation of measurements of ventilation-to-perfusion ratio inequality in the lung from expired gas

    NASA Technical Reports Server (NTRS)

    Prisk, G. Kim; Guy, Harold J B.; West, John B.; Reed, James W.

    2003-01-01

    The analysis of the gas in a single expirate has long been used to estimate the degree of ventilation-perfusion (Va/Q) inequality in the lung. To further validate this estimate, we examined three measures of Va/Q inhomogeneity calculated from a single full exhalation in nine anesthetized mongrel dogs under control conditions and after exposure to aerosolized methacholine. These measurements were then compared with arterial blood gases and with measurements of Va/Q inhomogeneity obtained using the multiple inert gas elimination technique. The slope of the instantaneous respiratory exchange ratio (R slope) vs. expired volume was poorly correlated with independent measures, probably because of the curvilinear nature of the relationship due to continuing gas exchange. When R was converted to the intrabreath Va/Q (iV/Q), the best index was the slope of iV/Q vs. volume over phase III (iV/Q slope). This was strongly correlated with independent measures, especially those relating to inhomogeneity of perfusion. The correlations for iV/Q slope and R slope considerably improved when only the first half of phase III was considered. We conclude that a useful noninvasive measurement of Va/Q inhomogeneity can be derived from the intrabreath respiratory exchange ratio.

  19. Lung-protective Ventilation in Patients with Brain Injury: A Multicenter Cross-sectional Study and Questionnaire Survey in China

    PubMed Central

    Luo, Xu-Ying; Hu, Ying-Hong; Cao, Xiang-Yuan; Kang, Yan; Liu, Li-Ping; Wang, Shou-Hong; Yu, Rong-Guo; Yu, Xiang-You; Zhang, Xia; Li, Bao-Shan; Ma, Zeng-Xiang; Weng, Yi-Bing; Zhang, Heng; Chen, De-Chang; Chen, Wei; Chen, Wen-Jin; Chen, Xiu-Mei; Du, Bin; Duan, Mei-Li; Hu, Jin; Huang, Yun-Feng; Jia, Gui-Jun; Li, Li-Hong; Liang, Yu-Min; Qin, Bing-Yu; Wang, Xian-Dong; Xiong, Jian; Yan, Li-Mei; Yang, Zheng-Ping; Dong, Chen-Ming; Wang, Dong-Xin; Zhan, Qing-Yuan; Fu, Shuang-Lin; Zhao, Lin; Huang, Qi-Bing; Xie, Ying-Guang; Huang, Xiao-Bo; Zhang, Guo-Bin; Xu, Wang-Bin; Xu, Yuan; Liu, Ya-Ling; Zhao, He-Ling; Sun, Rong-Qing; Sun, Ming; Cheng, Qing-Hong; Qu, Xin; Yang, Xiao-Feng; Xu, Ming; Shi, Zhong-Hua; Chen, Han; He, Xuan; Yang, Yan-Lin; Chen, Guang-Qiang; Sun, Xiu-Mei; Zhou, Jian-Xin

    2016-01-01

    Background: Over the years, the mechanical ventilation (MV) strategy has changed worldwide. The aim of the present study was to describe the ventilation practices, particularly lung-protective ventilation (LPV), among brain-injured patients in China. Methods: This study was a multicenter, 1-day, cross-sectional study in 47 Intensive Care Units (ICUs) across China. Mechanically ventilated patients (18 years and older) with brain injury in a participating ICU during the time of the study, including traumatic brain injury, stroke, postoperation with intracranial tumor, hypoxic-ischemic encephalopathy, intracranial infection, and idiopathic epilepsy, were enrolled. Demographic data, primary diagnoses, indications for MV, MV modes and settings, and prognoses on the 60th day were collected. Multivariable logistic analysis was used to assess factors that might affect the use of LPV. Results: A total of 104 patients were enrolled in the present study, 87 (83.7%) of whom were identified with severe brain injury based on a Glasgow Coma Scale ≤8 points. Synchronized intermittent mandatory ventilation (SIMV) was the most frequent ventilator mode, accounting for 46.2% of the entire cohort. The median tidal volume was set to 8.0 ml/kg (interquartile range [IQR], 7.0–8.9 ml/kg) of the predicted body weight; 50 (48.1%) patients received LPV. The median positive end-expiratory pressure (PEEP) was set to 5 cmH2O (IQR, 5–6 cmH2O). No PEEP values were higher than 10 cmH2O. Compared with partially mandatory ventilation, supportive and spontaneous ventilation practices were associated with LPV. There were no significant differences in mortality and MV duration between patients subjected to LPV and those were not. Conclusions: Among brain-injured patients in China, SIMV was the most frequent ventilation mode. Nearly one-half of the brain-injured patients received LPV. Patients under supportive and spontaneous ventilation were more likely to receive LPV. Trial Registration: Clinical

  20. Mechanical ventilation and thoracic artificial lung assistance during mechanical circulatory support with PUCA pump: in silico study.

    PubMed

    De Lazzari, Claudio; Genuini, Igino; Quatember, Bernhard; Fedele, Francesco

    2014-02-01

    Patients assisted with left ventricular assist device (LVAD) may require prolonged mechanical ventilatory assistance secondary to postoperative respiratory failure. The goal of this work is the study of the interdependent effects LVAD like pulsatile catheter (PUCA) pump and mechanical ventilatory support or thoracic artificial lung (TAL), by the hemodynamic point of view, using a numerical simulator of the human cardiovascular system. In the simulator, different circulatory sections are described using lumped parameter models. Lumped parameter models have been designed to describe the hydrodynamic behavior of both PUCA pump and thoracic artificial lung. Ventricular behavior atrial and septum functions were reproduced using variable elastance model. Starting from simulated pathological conditions we studied the effects produced on some hemodynamic variables by simultaneous PUCA pump, thoracic artificial lung or mechanical ventilation assistance. Thoracic artificial lung was applied in parallel or in hybrid mode. The effects of mechanical ventilation have been simulated by changing mean intrathoracic pressure value from -4 mmHg to +5 mmHg. The hemodynamic variables observed during the simulations, in different assisted conditions, were: left and right ventricular end systolic (diastolic) volume, systolic/diastolic aortic pressure, mean pulmonary arterial pressure, left and right mean atrial pressure, mean systemic venous pressure and the total blood flow. Results show that the application of PUCA (without mechanical ventilatory assistance) increases the total blood flow, reduces the left ventricular end systolic volume and increases the diastolic aortic pressure. Parallel TAL assistance increases the right ventricular end diastolic (systolic) volume reduction both when PUCA is switched "ON" and both when PUCA is switched "OFF". By switching "OFF" the PUCA pump, it seems that parallel thoracic artificial lung assistance produces a greater cardiac output (respect to

  1. Lung protective ventilation in patients undergoing major surgery: a systematic review incorporating a Bayesian approach

    PubMed Central

    Zhang, Zhongheng; Hu, Xiaoyun; Zhang, Xia; Zhu, Xiuqi; Chen, Liqian; Zhu, Li; Hu, Caibao; Du, Bin

    2015-01-01

    Objective Protective ventilation (PV) has been validated in patients with acute respiratory distress syndrome. However, the effect of PV in patients undergoing major surgery is controversial. The study aimed to explore the beneficial effect of PV on patients undergoing a major operation by systematic review and meta-analysis. Setting Various levels of medical centres. Participants Patients undergoing general anaesthesia. Interventions PV with low tidal volume. Primary and secondary outcome measures Study end points included acute lung injury (ALI), pneumonia, atelectasis, mortality, length of stay (LOS) in intensive care unit (ICU) and hospital. Methods Databases including PubMed, Scopus, EBSCO and EMBASE were searched from inception to May 2015. Search strategies consisted of terms related to PV and anaesthesia. We reported OR for binary outcomes including ALI, mortality, pneumonia, atelectasis and other adverse outcomes. Weighted mean difference was reported for continuous outcomes such as LOS in the ICU and hospital, pH value, partial pressure of carbon dioxide, oxygenation and duration of mechanical ventilation (MV). Main results A total of 22 citations were included in the systematic review and meta-analysis. PV had protective effect against the development of ALI as compared with the control group, with an OR of 0.41 (95% CI 0.19 to 0.87). PV tended to be beneficial with regard to the development of pneumonia (OR 0.46, 95% CI 0.16 to 1.28) and atelectasis (OR 0.68, 95% CI 0.46 to 1.01), but statistical significance was not reached. Other adverse outcomes such as new onset arrhythmia were significantly reduced with the use of PV (OR 0.47, 95% CI 0.48 to 0.93). Conclusions The study demonstrates that PV can reduce the risk of ALI in patients undergoing major surgery. However, there is insufficient evidence that such a beneficial effect can be translated to more clinically relevant outcomes such as mortality or duration of MV. Trial registration number The study

  2. Toll-like receptor 4 knockout ameliorates neuroinflammation due to lung-brain interaction in mechanically ventilated mice.

    PubMed

    Chen, Ting; Chen, Chang; Zhang, Zongze; Zou, Yufeng; Peng, Mian; Wang, Yanlin

    2016-08-01

    Toll-like receptor 4 (TLR4) is a crucial receptor in the innate immune system, and increasing evidence supports its role in inflammation, stress, and tissue injury, including injury to the lung and brain. We aimed to investigate the effects of TLR4 on neuroinflammation due to the lung-brain interaction in mechanically ventilated mice. Male wild-type (WT) C57BL/6 and TLR4 knockout (TLR4 KO) mice were divided into three groups: (1) control group (C): spontaneous breathing; (2) anesthesia group (A): spontaneous breathing under anesthesia; and (3) mechanical ventilation group (MV): 6h of MV under anesthesia. The behavioral responses of mice were tested with fear conditioning tests. The histological changes in the lung and brain were assessed using hematoxylin-eosin (HE) staining. The level of TLR4 mRNA in tissue was measured using reverse transcription-polymerase chain reaction (RT-PCR). The levels of inflammatory cytokines were measured with an enzyme-linked immunosorbent assay (ELISA). Microgliosis, astrocytosis, and the TLR4 immunoreactivity in the hippocampus were measured by double immunofluorescence. MV mice exhibited impaired cognition, and this impairment was less severe in TLR4 KO mice than in WT mice. In WT mice, MV increased TLR4 mRNA expression in the lung and brain. MV induced mild lung injury, which was prevented in TLR4 KO mice. MV mice exhibited increased levels of inflammatory cytokines, increased microglia and astrocyte activation. Microgliosis was alleviated in TLR4 KO mice. MV mice exhibited increased TLR4 immunoreactivity, which was expressed in microglia and astrocytes. These results demonstrate that TLR4 is involved in neuroinflammation due to the lung-brain interaction and that TLR4 KO ameliorates neuroinflammation due to lung-brain interaction after prolonged MV. In addition, Administration of a TLR4 antagonist (100μg/mice) to WT mice also significantly attenuated neuroinflammation of lung-brain interaction due to prolonged MV. TLR4 antagonism

  3. Effect of lung-protective ventilation with lower tidal volumes on clinical outcomes among patients undergoing surgery: a meta-analysis of randomized controlled trials

    PubMed Central

    Gu, Wan-Jie; Wang, Fei; Liu, Jing-Chen

    2015-01-01

    Background: In anesthetized patients undergoing surgery, the role of lung-protective ventilation with lower tidal volumes is unclear. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of this ventilation strategy on postoperative outcomes. Methods: We searched electronic databases from inception through September 2014. We included RCTs that compared protective ventilation with lower tidal volumes and conventional ventilation with higher tidal volumes in anesthetized adults undergoing surgery. We pooled outcomes using a random-effects model. The primary outcome measures were lung injury and pulmonary infection. Results: We included 19 trials (n = 1348). Compared with patients in the control group, those who received lung-protective ventilation had a decreased risk of lung injury (risk ratio [RR] 0.36, 95% confidence interval [CI] 0.17 to 0.78; I2 = 0%) and pulmonary infection (RR 0.46, 95% CI 0.26 to 0.83; I2 = 8%), and higher levels of arterial partial pressure of carbon dioxide (standardized mean difference 0.47, 95% CI 0.18 to 0.75; I2 = 65%). No significant differences were observed between the patient groups in atelectasis, mortality, length of hospital stay, length of stay in the intensive care unit or the ratio of arterial partial pressure of oxygen to fraction of inspired oxygen. Interpretation: Anesthetized patients who received ventilation with lower tidal volumes during surgery had a lower risk of lung injury and pulmonary infection than those given conventional ventilation with higher tidal volumes. Implementation of a lung-protective ventilation strategy with lower tidal volumes may lower the incidence of these outcomes. PMID:25512653

  4. Household Ventilation May Reduce Effects of Indoor Air Pollutants for Prevention of Lung Cancer: A Case-Control Study in a Chinese Population

    PubMed Central

    Han, Ren-Qiang; Zhang, Xiao-Feng; Wang, Xu-Shan; Liu, Ai-Ming; Zhou, Jin-Yi; Lu, Qing-Yi; Kim, Claire H.; Mu, Lina; Zhang, Zuo-Feng; Zhao, Jin-Kou

    2014-01-01

    Background Although the International Agency for Research on Cancer (IARC) has classified various indoor air pollutants as carcinogenic to humans, few studies evaluated the role of household ventilation in reducing the impact of indoor air pollutants on lung cancer risk. Objectives To explore the association between household ventilation and lung cancer. Methods A population-based case-control study was conducted in a Chinese population from 2003 to 2010. Epidemiologic and household ventilation data were collected using a standardized questionnaire. Unconditional logistic regression was employed to estimate adjusted odds ratios (ORadj) and their 95% confidence intervals (CI). Results Among 1,424 lung cancer cases and 4,543 healthy controls, inverse associations were observed for good ventilation in the kitchen (ORadj = 0.86, 95% CI: 0.75, 0.98), bedroom (ORadj = 0.90, 95% CI: 0.79, 1.03), and both kitchen and bedroom (ORadj = 0.87, 95% CI: 0.75, 1.00). Stratified analyses showed lung cancer inversely associated with good ventilation among active smokers (ORadj = 0.85, 95% CI: 0.72, 1.00), secondhand smokers at home (ORadj = 0.77, 95% CI: 0.63, 0.94), and those exposed to high-temperature cooking oil fumes (ORadj = 0.82, 95% CI: 0.68, 0.99). Additive interactions were found between household ventilation and secondhand smoke at home as well as number of household pollutant sources. Conclusions A protective association was observed between good ventilation of households and lung cancer, most likely through the reduction of exposure to indoor air pollutants, indicating ventilation may serve as one of the preventive measures for lung cancer, in addition to tobacco cessation. PMID:25019554

  5. Changes in distribution of lung perfusion and ventilation at rest and during maximal exercise

    SciTech Connect

    Mohsenifar, Z.; Ross, M.D.; Waxman, A.; Goldbach, P.; Koerner, S.K.

    1985-03-01

    A new method for evaluation of changes in the distribution of pulmonary perfusion and ventilation during exercise was applied to normal male volunteers. Ventilation and perfusion scans were done with the subjects seated on a bicycle ergometer. The resting studies utilized krypton 81 (/sup 81m/Kr) for ventilation and technetium /sup 99m/ (/sup 99m/Tc) macroaggregate albumin intravenously for perfusion. Exercise studies were done when 80 percent of maximum predicted heart rate was maintained for five minutes and utilized /sup 81m/Kr for ventilation and a tenfold dose of /sup 99m/Tc for perfusion. Higher dose of /sup 99m/Tc would minimize the effect of radioactivity left over from the resting study. This method allowed us to assess changes in ventilation and perfusion in normal subjects induced by exercise, but may also be applicable in a variety of cardiopulmonary conditions that affect pulmonary ventilation and perfusion or both.

  6. Effects of sevoflurane and propofol on the inflammatory response and pulmonary function of perioperative patients with one-lung ventilation.

    PubMed

    Jin, Yanwu; Zhao, Xin; Li, Haibo; Wang, Zhigang; Wang, Duanyu

    2013-09-01

    This study compared the effects of sevoflurane and propofol on the inflammatory response and pulmonary function of patients with lung cancer during the perioperative period. Forty patients who underwent a selective resection of the inferior lobe of the left lung were randomly divided into two groups, with one group anesthetized with sevoflurane and the other with propofol (groups S and P, respectively). Radial arterial and mixed venous blood were extracted for blood gas analysis, in order to calculate the alveolar-arterial oxygen partial pressure difference (PA-aDO2), respiratory index (RI) and pulmonary shunt ratio (Qs/Qt) prior to the induction of anesthesia (T0), prior to one-lung ventilation (OLV) (T1), 1 h subsequent to the commencement of OLV (T2), 1 h following restoration of two-lung ventilation (T3), 2 h following restoration of two-lung ventilation (T4) and 24 h post-surgery (T5). In addition, blood was extracted from the radial artery at T0, T1, T2, T3, T4 and T5 in order to detect the presence of tumor necrosis factor-α (TNF-α), IL-6 and IL-10 in the blood serum. Between T1 and T4, the tidal volume, airway plateau pressure and end-expiratory positive airway pressure were recorded, in order to calculate the lung dynamic compliance (Cdyn). Heart rate, mean arterial pressure, central venous pressure, cardiac output and the duration of OLV (OLV-T) were recorded at T0-5. Compared with T0, the levels of TNF-α, IL-6 and IL-10 significantly increased during T2 to T4 in both groups (P<0.05). PA-aDO2 and RI increased during T1 to T4, and Qs/Qt increased at T2 (P<0.05). Compared with T1, Cdyn decreased during T2 to T4 in the S group, whereas Cdyn was reduced at T2 in the P group (P<0.05). Compared with the P group, TNF-α level increased and IL-10 decreased at T3 and T4 in the S group. PA-aDO2 and RI increased, but Cdyn decreased at T2 and T3 in the S group. Qs/Qt increased at T2 in the S group. The results of the present study demonstrated that, in comparison

  7. Pulmonary ventilation/perfusion scan

    MedlinePlus

    V/Q scan; Ventilation/perfusion scan; Lung ventilation/perfusion scan ... A pulmonary ventilation/perfusion scan is actually two tests. They may be done separately or together. During the perfusion scan, a health care ...

  8. Diagnosis Accuracy of Mean Arterial Pressure Variation during a Lung Recruitment Maneuver to Predict Fluid Responsiveness in Thoracic Surgery with One-Lung Ventilation

    PubMed Central

    Kang, Woon-Seok; Oh, Chung-Sik; Park, Chulmin; Shin, Bo Mi; Yoon, Tae-Gyoon; Rhee, Ka-Young; Woo, Nam-Sik

    2016-01-01

    Background. Lung recruitment maneuver (LRM) during thoracic surgery can reduce systemic venous return and resulting drop in systemic blood pressure depends on the patient's fluid status. We hypothesized that changes in systemic blood pressure during the transition in LRM from one-lung ventilation (OLV) to two-lung ventilation (TLV) may provide an index to predict fluid responsiveness. Methods. Hemodynamic parameters were measured before LRM (T0); after LRM at the time of the lowest mean arterial blood pressure (MAP) (T1) and at 3 minutes (T2); before fluid administration (T3); and 5 minutes after ending it (T4). If the stroke volume index increased by >25% following 10 mL/kg colloid administration for 30 minutes, then the patients were assigned to responder group. Results. Changes in MAP, central venous pressure (CVP), and stroke volume variation (SVV) between T0 and T1 were significantly larger in responders. Areas under the curve for change in MAP, CVP, and SVV were 0.852, 0.759, and 0.820, respectively; the optimal threshold values for distinguishment of responders were 9.5 mmHg, 0.5 mmHg, and 3.5%, respectively. Conclusions. The change in the MAP associated with LRM at the OLV to TLV conversion appears to be a useful indicator of fluid responsiveness after thoracic surgery. Trial Registration. This trial is registered at Clinical Research Information Service with KCT0000774.

  9. Influence of hyperoxia and mechanical ventilation in lung inflammation and diaphragm function in aged versus adult rats.

    PubMed

    Andrade, P V; dos Santos, J M; Silva, H C A; Wilbert, D D; Cavassani, S S; Oliveira-Júnior, I S

    2014-04-01

    Although assist ventilation with FIO2 0.21 is the preferable mode of ventilation in the intensive care unit, sometimes controlled ventilation with hyperoxia is needed. But the impact of this setting has not been extensively studied in elderly subjects. We hypothesized that a high fraction of inspired oxygen (FiO(2)) and controlled mechanical ventilation (CMV) is associated with greater deleterious effects in old compared to adult subjects. Adult and old rats were submitted to CMV with low tidal volume (6 ml/kg) and FiO(2) 1 during 3 or 6 h. Arterial blood gas samples were measured at 0, 60 and 180 min (four groups: old and adult rats, 3 or 6 h of CMV), and additionally at 360 min (two groups: old and adult rats, 6 h of CMV). Furthermore, total protein content (TPC) and tumor necrosis factor-alpha (TNF-α) in bronchoalveolar lavage were assessed; lung tissue was used for malondialdehyde and histological analyses, and the diaphragm for measurement of contractile function. Arterial blood gas analysis showed an initial (60 min) greater PaO(2) in elderly versus adult animals; after that time, elderly animals had lowers pH and PaO(2), and greater PaCO(2). After 3 h of CMV, TPC and TNF-α levels were higher in the old compared with the adult group (P < 0.05). After 6 h of MV, malondialdehyde was significantly higher in elderly compared with the adult animals (P < 0.05). Histological analysis showed leukocyte infiltration and edema, greater in old animals. In diaphragm, twitch contraction with caffeine significantly declined after 6 h of CMV only for the elderly group. These data support the hypothesis that relatively short-term CMV with low tidal volume and hyperoxia has greatest impact in elderly rats, decreasing diaphragmatic contractile function and increasing lung inflammation.

  10. Numerical investigation of aerosolized drug delivery in the human lungs under mechanical ventilator conditions

    NASA Astrophysics Data System (ADS)

    Vanrhein, Timothy; Banerjee, Arindam

    2010-11-01

    Particle deposition for aerosolized drug delivery in the human airways is heavily dependent upon flow conditions. Numerical modeling techniques have proven valuable for determining particle deposition characteristics under steady flow conditions. For the case of patients under mechanical ventilation, however, flow conditions change drastically and there is an increased importance to understand particle deposition characteristics. This study focuses on mechanically ventilated conditions in the upper trachea-bronchial (TB) region of the human airways. Solution of the continuous phase flow is done under ventilator waveform conditions with a suitable turbulence model in conjunction with a realistic model of upper TB airways. A discrete phase Euler-Lagrange approach is applied to solve for particle deposition characteristics with a focus on the effect of the ventilator inlet waveform. The purpose of this study is to accurately model flow conditions in the upper TB airways under mechanically ventilated conditions with a focus on real-time patient specific targeted aerosolized drug delivery.

  11. Changes in 99mTechnegas ventilation lung scan in a newborn with absent pulmonary valve syndrome.

    PubMed

    Takahashi, K; Kuwahara, T; Nagatsu, M

    2001-11-01

    A newborn infant with tetralogy of Fallot and absent pulmonary valve was successfully corrected in two stages. Absent pulmonary valve syndrome presenting in early infancy manifests severe respiratory symptoms that still make challenging both management and surgical treatment. This is ascribed to tracheobronchial compression by the extremely dilated pulmonary arteries, and to the resultant pulmonary obstructive lesions. We report herein the first findings of 99mTechnegas ventilation lung scanning in an infant with the syndrome to assess the pulmonary obstructive lesions. PMID:11813924

  12. Ventilation defects observed with hyperpolarized 3He magnetic resonance imaging in a mouse model of acute lung injury.

    PubMed

    Thomas, Abe C; Nouls, John C; Driehuys, Bastiaan; Voltz, James W; Fubara, Boma; Foley, Julie; Bradbury, J Alyce; Zeldin, Darryl C

    2011-05-01

    Regions of diminished ventilation are often evident during functional pulmonary imaging studies, including hyperpolarized gas magnetic resonance imaging (MRI), positron emission tomography, and computed tomography (CT). The objective of this study was to characterize the hypointense regions observed via (3)He MRI in a murine model of acute lung injury. LPS at doses ranging from 15-50 μg was intratracheally administered to C57BL/6 mice under anesthesia. Four hours after exposure to either LPS or saline vehicle, mice were imaged via hyperpolarized (3)He MRI. All images were evaluated to identify regions of hypointense signals. Lungs were then characterized by conventional histology, or used to obtain tissue samples from regions of normal and hypointense (3)He signals and analyzed for cytokine content. The characterization of (3)He MRI images identified three distinct types of hypointense patterns: persistent defects, atelectatic defects, and dorsal lucencies. Persistent defects were associated with the administration of LPS. The number of persistent defects depended on the dose of LPS, with a significant increase in mean number of defects in 30-50-μg LPS-dosed mice versus saline-treated control mice. Atelectatic defects predominated in LPS-dosed mice under conditions of low-volume ventilation, and could be reversed with deep inspiration. Dorsal lucencies were present in nearly all mice studied, regardless of the experimental conditions, including control animals that did not receive LPS. A comparison of (3)He MRI with histopathology did not identify tissue abnormalities in regions of low (3)He signal, with the exception of a single region of atelectasis in one mouse. Furthermore, no statistically significant differences were evident in concentrations of IL-1β, IL-6, macrophage inflammatory protein (MIP)-1α, MIP-2, chemokine (C-X-C motif) ligand 1 (KC), TNFα, and monocyte chemotactic protein (MCP)-1 between hypointense and normally ventilated lung regions in LPS

  13. NEUTROPHIL DEPLETION ATTENUATES INTERLEUKIN-8 PRODUCTION IN MILD-OVERSTRETCHED VENTILATED NORMAL RABBIT LUNG

    EPA Science Inventory

    OBJECTIVE: Acute lung injury induced by lung overstretch is associated with neutrophil influx, but the pathogenic role of neutrophils in overstretch-induced lung injury remains unclear. DESIGN: To assess the contribution of neutrophils, we compared the effects of noninjurious lar...

  14. Treatment of sepsis and ARDS with extracorporeal membrane oxygenation and interventional lung assist membrane ventilator in a patient with acute lymphoblastic leukemia.

    PubMed

    Gorjup, Vojka; Fister, Misa; Noc, Marko; Rajic, Vladan; Ribaric, Suada Filekovic

    2012-07-01

    We report an 18-year-old ice skater with acute lymphoblast leukemia. She developed Staphylococcus epidermidis bacteremia, severe sepsis, septic shock, and ARDS following chemotherapy-induced severe bone marrow failure. She was successfully treated with extraordinary life support measures, which included extracorporeal membrane oxygenation, double lumen lung ventilation for management of hemoptysis, and lung assist membrane ventilation. After 57 days of ICU treatment and a year of rehabilitation, the patient has fully regained her functional status, is now finishing high school, and is ice skating again.

  15. Dead space reduction by Kolobow's endotracheal tube does not justify the waiving of volume monitoring in small, ventilated lungs.

    PubMed

    Proquitté, Hans; Wendel, Rena; Roehr, Charles C; Wauer, Roland R; Schmalisch, Gerd

    2014-12-01

    In ventilated preterm infants the flow sensor contributes significantly to the total apparatus dead space, which may impair gas exchange. The aim of the study was to quantify to which extent a dead space reduced Kolobow tube (KB) without flow sensor improves the gas exchange compared with a conventional ventilator circuit with flow sensor [Babylog 8000 (BL)]. In a cross-over trial in 14 tracheotomized, surfactant-depleted (saline lavage) and mechanically ventilated newborn piglets (age <12 h; body weight 705-1200 g) BL and KB was applied alternately for 15 min and blood gases were recorded. The inner diameter of the endotracheal tube was 3.6 mm and the apparatus dead space of BL and KB including the endotracheal tube were 3.0 and 1.34 mL. Despite a 50 % apparatus dead space reduction with KB compared to BL statistically significant improvements were only observed for body weights <900 g. In this weight group median paCO2 was decreased by 5 mmHg (p < 0.01), whereas the improvement decreased with decreasing baseline paCO2. Furthermore, median paO2 was increased by 4 mmHg (p < 0.05) and O2 saturation was increased by 2.5 % (p < 0.05). No significant changes were seen in the circulatory parameters. In very small, ventilated lungs the use of KB improved the gas exchange; however, the improvement was moderate and does not justify the waiving of volume monitoring.

  16. Automated continuous quantitative measurement of proximal airways on dynamic ventilation CT: initial experience using an ex vivo porcine lung phantom

    PubMed Central

    Yamashiro, Tsuneo; Tsubakimoto, Maho; Nagatani, Yukihiro; Moriya, Hiroshi; Sakuma, Kotaro; Tsukagoshi, Shinsuke; Inokawa, Hiroyasu; Kimoto, Tatsuya; Teramoto, Ryuichi; Murayama, Sadayuki

    2015-01-01

    Background The purpose of this study was to evaluate the feasibility of continuous quantitative measurement of the proximal airways, using dynamic ventilation computed tomography (CT) and our research software. Methods A porcine lung that was removed during meat processing was ventilated inside a chest phantom by a negative pressure cylinder (eight times per minute). This chest phantom with imitated respiratory movement was scanned by a 320-row area-detector CT scanner for approximately 9 seconds as dynamic ventilatory scanning. Obtained volume data were reconstructed every 0.35 seconds (total 8.4 seconds with 24 frames) as three-dimensional images and stored in our research software. The software automatically traced a designated airway point in all frames and measured the cross-sectional luminal area and wall area percent (WA%). The cross-sectional luminal area and WA% of the trachea and right main bronchus (RMB) were measured for this study. Two radiologists evaluated the traceability of all measurable airway points of the trachea and RMB using a three-point scale. Results It was judged that the software satisfactorily traced airway points throughout the dynamic ventilation CT (mean score, 2.64 at the trachea and 2.84 at the RMB). From the maximum inspiratory frame to the maximum expiratory frame, the cross-sectional luminal area of the trachea decreased 17.7% and that of the RMB 29.0%, whereas the WA% of the trachea increased 6.6% and that of the RMB 11.1%. Conclusion It is feasible to measure airway dimensions automatically at designated points on dynamic ventilation CT using research software. This technique can be applied to various airway and obstructive diseases. PMID:26445535

  17. Neutrophil elastase inhibitor reduces ventilation-induced lung injury via nuclear factor-κB and NF-κB repressing factor in mice.

    PubMed

    Li, Li-Fu; Lai, Yi-Ting; Chang, Chih-Hao; Lin, Meng-Chih; Liu, Yung-Yang; Kao, Kuo-Chin; Tsai, Ying-Huang

    2014-04-11

    Mechanical ventilation used in patients with acute lung injury can damage pulmonary epithelial cells through production of inflammatory cytokines, oxygen radicals, and neutrophil infiltration, termed ventilator-induced lung injury. Neutrophil elastase, nuclear factor-κB (NF-κB), and NF-κB repressing factor (NRF) have previously been shown to participate in the regulation of macrophage inflammatory protein-2 (MIP-2) during airway inflammation. However, the mechanisms regulating interactions among mechanical ventilation, neutrophil influx, and NF-κB/NRF remain unclear. Thus, we hypothesized that neutrophil elastase inhibitor attenuated ventilation-induced neutrophil recruitment and MIP-2 production through inhibition of the NF-κB/NRF pathway. Male C57BL/6 mice were exposed to low-tidal-volume (6 mL/kg) or high-tidal-volume (30 mL/kg) mechanical ventilation using room air with or without 2 µg/g NF-κB inhibitor SN50 or 6 µg/g NRF short interfering RNA or 100 µg/g neutrophil elastase inhibitor administration. Nonventilated mice served as a control group. Evan blue dye, lung wet-to-dry weight ratio, free radicals, myeloperoxidase, histopathologic grading of lung tissue, inflammatory cytokines, Western blot of NF-κB and NRF, and gene expression of NRF were measured to establish the extent of lung injury. Neutrophil elastase inhibitor ameliorated high-tidal-volume ventilation-induced lung injury, neutrophil influx, production of MIP-2 and malondialdehyde, activation of NF-κB and NRF, apoptotic epithelial cell death, and disruption of bronchial microstructure in mice. Mechanical stretch-augmented acute lung injury was also attenuated through pharmacological inhibition of NF-κB activity by SN50 and NRF expression by NRF short interfering RNA. Our data suggest that neutrophil elastase inhibitor attenuates high-tidal-volume mechanical ventilation-induced neutrophil influx, oxidative stress, and production of MIP-2, at least partly, through inhibition of

  18. High tidal volume mechanical ventilation-induced lung injury in rats is greater after acid instillation than after sepsis-induced acute lung injury, but does not increase systemic inflammation: an experimental study

    PubMed Central

    2011-01-01

    Background To examine whether acute lung injury from direct and indirect origins differ in susceptibility to ventilator-induced lung injury (VILI) and resultant systemic inflammatory responses. Methods Rats were challenged by acid instillation or 24 h of sepsis induced by cecal ligation and puncture, followed by mechanical ventilation (MV) with either a low tidal volume (Vt) of 6 mL/kg and 5 cm H2O positive end-expiratory pressure (PEEP; LVt acid, LVt sepsis) or with a high Vt of 15 mL/kg and no PEEP (HVt acid, HVt sepsis). Rats sacrificed immediately after acid instillation and non-ventilated septic animals served as controls. Hemodynamic and respiratory variables were monitored. After 4 h, lung wet to dry (W/D) weight ratios, histological lung injury and plasma mediator concentrations were measured. Results Oxygenation and lung compliance decreased after acid instillation as compared to sepsis. Additionally, W/D weight ratios and histological lung injury scores increased after acid instillation as compared to sepsis. MV increased W/D weight ratio and lung injury score, however this effect was mainly attributable to HVt ventilation after acid instillation. Similarly, effects of HVt on oxygenation were only observed after acid instillation. HVt during sepsis did not further affect oxygenation, compliance, W/D weight ratio or lung injury score. Plasma interleukin-6 and tumour necrosis factor-α concentrations were increased after acid instillation as compared to sepsis, but plasma intercellular adhesion molecule-1 concentration increased during sepsis only. In contrast to lung injury parameters, no additional effects of HVt MV after acid instillation on plasma mediator concentrations were observed. Conclusions During MV more severe lung injury develops after acid instillation as compared to sepsis. HVt causes VILI after acid instillation, but not during sepsis. However, this differential effect was not observed in the systemic release of mediators. PMID:22204611

  19. Positive indium-111 leukocyte scintigraphy in a skeletal metastasis

    SciTech Connect

    Sfakianakis, G.N.; Mnaymneh, W.; Ghandur-Mnaymneh, L.; Al-Sheikh, W.; Hourani, M.; Heal, A.

    1982-09-01

    Indium-111 scintigraphy is a method proposed for specific diagnosis and localization of focal infection. It has been found that, in general, cancers did not visualize with leukocyte scintigraphy. In this article, a case of positive indium-111 leukocyte scintigrams of a foot metstasis from a mucoepidermoid carcinoma of the lung is reported. (JMT)

  20. Hot spot(s) of the lung in technetium-99m albumin colloid liver-spleen scintigraphy: case report

    SciTech Connect

    Shih, W.J.; Brandenburg, S.; Coupal, J.J.; Sullivan, J.D.; Beeler, J.A.; Magoun, S.; Ryo, U.Y.

    1988-06-01

    The authors replaced /sup 99m/Tc albumin colloid for /sup 99m/Tc sulfur colloid as a radiopharmaceutical for liver-spleen imaging and found two instances of hot spot(s) in the lung. The preparation procedure of albumin colloid is easier and more convenient as compared to that of sulfur colloid. Whereas replacement of /sup 99m/Tc sulfur colloid by /sup 99m/Tc albumin colloid is inevitable, it should be emphasized that one should avoid blood withdrawal in the syringe containing albumin colloid to prevent formation of clot(s) during the venous puncture for /sup 99m/Tc albumin colloid.

  1. Manual Ventilation and Sustained Lung Inflation in an Experimental Model: Influence of Equipment Type and Operator’s Training

    PubMed Central

    Mascaretti, Renata Suman; Vale, Luciana Assis; Haddad, Luciana Branco

    2016-01-01

    Aim To compare the influence of devices for manual ventilation and individual experience on the applied respiratory mechanics and sustained lung inflation. Methods A total of 114 instructors and non-instructors from the Neonatal Resuscitation Program of the Brazilian Society of Pediatrics participated in this study. Participants ventilated an intubated manikin. To evaluate respiratory mechanics and sustained lung inflation parameters, a direct comparison was made between the self-inflating bag and the T-shaped resuscitator (T-piece), followed by an analysis of the effectiveness of the equipment according to the participants’ education and training. Results A difference between equipment types was observed for the tidal volume, with a median (interquartile range) of 28.5 mL (12.6) for the self-inflating bag and 20.1 mL (8.4) for the T-piece in the instructor group and 31.6 mL (14) for the self-inflating bag and 22.3 mL (8.8) for the T-piece in the non-instructor group. Higher inspiratory time values were observed with the T-piece in both groups of professionals, with no significant difference between them. The operator’s ability to maintain the target pressure over the 10 seconds of sustained lung inflation was evaluated using the area under the pressure-time curve and was 1.7-fold higher with the use of the T-piece. Inspiratory pressure and mean airway pressure applied during sustained lung inflation were greater with the self-inflating bag, as evaluated between the beginning and the end of the procedure. Conclusion The T-piece resulted in lower tidal volume and higher inspiratory time values, irrespective of the operator’s experience, and increased the ease of performing the sustained lung inflation maneuver, as demonstrated by the maintenance of target pressure for the desired period and a higher mean airway pressure than that obtained using the self-inflating bag. PMID:26859896

  2. Metabolic acidosis may be as protective as hypercapnic acidosis in an ex-vivo model of severe ventilator-induced lung injury: a pilot study

    PubMed Central

    2011-01-01

    Background There is mounting experimental evidence that hypercapnic acidosis protects against lung injury. However, it is unclear if acidosis per se rather than hypercapnia is responsible for this beneficial effect. Therefore, we sought to evaluate the effects of hypercapnic (respiratory) versus normocapnic (metabolic) acidosis in an ex vivo model of ventilator-induced lung injury (VILI). Methods Sixty New Zealand white rabbit ventilated and perfused heart-lung preparations were used. Six study groups were evaluated. Respiratory acidosis (RA), metabolic acidosis (MA) and normocapnic-normoxic (Control - C) groups were randomized into high and low peak inspiratory pressures, respectively. Each preparation was ventilated for 1 hour according to a standardized ventilation protocol. Lung injury was evaluated by means of pulmonary edema formation (weight gain), changes in ultrafiltration coefficient, mean pulmonary artery pressure changes as well as histological alterations. Results HPC group gained significantly greater weight than HPMA, HPRA and all three LP groups (P = 0.024), while no difference was observed between HPMA and HPRA groups regarding weight gain. Neither group differ on ultrafiltration coefficient. HPMA group experienced greater increase in the mean pulmonary artery pressure at 20 min (P = 0.0276) and 40 min (P = 0.0012) compared with all other groups. Histology scores were significantly greater in HP vs. LP groups (p < 0.001). Conclusions In our experimental VILI model both metabolic acidosis and hypercapnic acidosis attenuated VILI-induced pulmonary edema implying a mechanism other than possible synergistic effects of acidosis with CO2 for VILI attenuation. PMID:21486492

  3. Liver scintigraphy in ponies

    SciTech Connect

    Theodorakis, M.C.; Bermudez, A.J.; Manning, J.P.; Koritz, G.D.; Hillidge, C.J.

    1982-09-01

    Six derivatives of ethylenediamine-N,N'-bis (alpha-2-hydroxy phenyl) acetic acid labeled with /sup 99m/Tc were prepared and their imaging qualities evaluated in ponies. The 6 agents produced good scintigraphic images of certain structures of the liver in the pony. For each agent, 13 different scans were taken. Dorsal views of the left lateral, right lateral, and quadrate lobe were obtained with dorsal scans. Left lateral and left lateral oblique (45 degrees) scans provided a left lateral view of the left lobe and a medial view of the right lateral lobe. Right lateral scans revealed the right lateral and quadrate lobes. Administration of /sup 99m/Tc-labeled colloids which are commonly used in other species for liver scintigraphy resulted in extensive lung uptake in the pony.

  4. A novel combination of the Arndt endobronchial blocker and the laryngeal mask airway ProSeal™ provides one-lung ventilation for thoracic surgery

    PubMed Central

    LI, QIONG; LI, PEIYING; XU, JIANGHUI; GU, HUAHUA; MA, QINYUN; PANG, LIEWEN; LIANG, WEIMIN

    2014-01-01

    In this study, the feasibility and performance of the combination of the Arndt endobronchial blocker and the laryngeal mask airway (LMA) ProSeal™ in airway establishment, ventilation, oxygenation and lung isolation was evaluated. Fifty-five patients undergoing general anesthesia for elective thoracic surgeries were randomly allocated to group Arndt (n=26) or group double-lumen tube (DLT; n=29). Data concerning post-operative airway morbidity, ease of insertion, hemodynamics, lung collapse, ventilators, oxygenation and ventilation were collected for analysis. Compared with group DLT, group Arndt showed a significantly attenuated hemodynamic response to intubation (blood pressure, 149±31 vs. 115±16 mmHg; heart rate, 86±15 vs. 68±15 bpm), less severe injuries to the bronchus (injury score, 1.4±0.2 vs. 0.4±0.1) and vocal cords (injury score, 1.3±0.2 vs. 0.6±0.1), and lower incidences of post-operative sore throat and hoarseness. Furthermore, the novel combination of the Arndt and the LMA ProSeal showed similar ease of airway establishment, comparable ventilation and oxygenation performance, and an analogous lung isolation effect to DLT. The novel combined use of the Arndt endobronchial blocker and the LMA ProSeal can serve as a promising alternative for thoracic procedures requiring one-lung ventilation. The less traumatic properties and equally ideal lung isolation are likely to promote its use in rapidly spreading minimally invasive thoracic surgeries. PMID:25289071

  5. A risk assessment of multiple use of an aerosol system compared with single use for lung ventilation scans.

    PubMed

    Belton, I P; Burford, D; Early, M Y

    1997-07-01

    Over 300 99Tc(m)-DTPA aerosol lung ventilation scans are performed at Leicester Royal Infirmary each year. Current practice is to re-use the nebulizer circuits up to five times over a maximum of 1 week. Following a visit from the hospital infection control team, this practice was questioned and, therefore, a risk assessment was carried out. This compared the risks of multiple use of ventilation circuits with single use. A survey was also carried out to try and establish current practice in other departments. The risk assesment showed that both single and multiple use of nebulizer circuits can have a high risk. The risks associated with the former were radiation safety and/or financial, and the risk with the latter was cross-infection. The survey showed that multiple use is certainly common practice within the UK. Therefore, in coming to a decision on which practice to adopt, these risks must be considered most carefully in the context of the local environment.

  6. Ventilation-perfusion relationships in the lung during head-out water immersion

    NASA Technical Reports Server (NTRS)

    Derion, Toniann; Guy, Harold J. B.; Tsukimoto, Koichi; Schaffartzik, Walter; Prediletto, Renato; Poole, David C.; Knight, Douglas R.; Wagner, Peter D.

    1992-01-01

    Mechanisms of altered pulmonary gas exchange during water immersion were studied in 12 normal males: 6 young (aged 20-29) and 6 older (aged 40-45). It is concluded that, in young subjects with closing volume (CV) less than expiratory reserve volume (ERV), gas exchange was enhanced during immersion, because normal ventilation-perfusion relations were preserved, and by mass balance, the ventilation/O2 uptake changes elevated arterial P(O2). In older males with CV greater than ERV and 52 percent of tidal volume below CV, immersion-induced airways closure during tidal breathing was associated with minimally increased shunt that did not significantly impair gas exchange. It is suggested that airways closure of this degree is of little importance to gas exchange.

  7. [Ventilation mechanics in the premature and the newborn. I. Statistical measurements of the isolated lungs].

    PubMed

    Wierich, W

    1976-01-01

    On 31 pairs of lungs from still borns and newborns of differing stages of maturation and age (23rd week of gestation up to the 24th week after birth) statical measurements including liquid fillings were performed. On account of the histo-mechanical tests as well as morphological and clinical data, the group could be divided into normal lungs and lungs with decreased surfactant activity. Between the 35th week of gestation and the 5th week after birth a marked increase in pulmonary maturation with unproportional changes of the histomechanical values could be demonstrated. In lungs with decreased surfactant activity the influence of life span upon the mechanical properties of pulmonary tissue could be shown. The high surface tension decreases, presumably on account of surfactant synthesis, while the values of tissue elasticity decrease as a result of overstretching.

  8. Mechanical Ventilation and Bronchopulmonary Dysplasia.

    PubMed

    Keszler, Martin; Sant'Anna, Guilherme

    2015-12-01

    Mechanical ventilation is an important potentially modifiable risk factor for the development of bronchopulmonary dysplasia. Effective use of noninvasive respiratory support reduces the risk of lung injury. Lung volume recruitment and avoidance of excessive tidal volume are key elements of lung-protective ventilation strategies. Avoidance of oxidative stress, less invasive methods of surfactant administration, and high-frequency ventilation are also important factors in lung injury prevention. PMID:26593078

  9. TU-F-17A-09: Four-Dimensional Cone Beam CT Ventilation Imaging Can Detect Interfraction Lung Function Variations for Locally Advanced Lung Cancer Patients

    SciTech Connect

    Kipritidis, J; Keall, P; Hugo, G; Weiss, E; Williamson, J

    2014-06-15

    Purpose: Four-dimensional cone beam CT ventilation imaging (4D-CBCT VI) is a novel functional lung imaging modality requiring validation. We hypothesize that 4D-CBCT VI satisfies a necessary condition for validity: that intrafraction variations (e.g. due to poor 4D-CBCT image quality) are substantially different to interfraction variations (e.g. due to changes in underlying function). We perform the first comparison of intrafraction (pre/post fraction) and interfraction (week-to-week) 4D-CBCT VIs for locally advanced non small cell lung cancer (LA NSCLC) patients undergoing radiation therapy. Methods: A total of 215 4D-CBCT scans were acquired for 19 LA NSCLC patients over 4-6 weeks of radiation therapy, including 75 pairs of pre-/post-fraction scans on the same day. 4D-CBCT VIs were obtained by applying state-of-the-art, B-spline deformable image registration to obtain the Jacobian determinant of deformation between the end-exhale and end-inhale phases. All VIs were deformably registered to the corresponding first day scan, normalized between the 10th and 90th percentile values and cropped to the ipsilateral lung only. Intrafraction variations were assessed by computing the mean and standard deviation of voxel-wise differences between all same-day pairs of pre-/post-fraction VIs. Interfraction differences were computed between first-day VIs and treatment weeks 2, 4 and 6 for all 19 patients. We tested the hypothesis by comparing cumulative distribution functions (CDFs) of intrafraction and interfraction ventilation differences using two-sided Kolmogorov-Smirnov goodness-of-fit tests. Results: The (mean ± std. dev.) of intrafraction differences was (−0.007 ± 0.079). Interfraction differences for weeks 2, 4 and 6 were (−0.035 ± 0.103), (−0.006 ± 0.094) and (−0.019 ± 0.127) respectively. For week 2, the changes in CDFs for intrafraction and interfraction differences approached statistical significance (p=0.099). Conclusion: We have shown that 4D-CBCT VI

  10. The gravitational distribution of ventilation-perfusion ratio is more uniform in prone than supine posture in the normal human lung.

    PubMed

    Henderson, A Cortney; Sá, Rui Carlos; Theilmann, Rebecca J; Buxton, Richard B; Prisk, G Kim; Hopkins, Susan R

    2013-08-01

    The gravitational gradient of intrapleural pressure is suggested to be less in prone posture than supine. Thus the gravitational distribution of ventilation is expected to be more uniform prone, potentially affecting regional ventilation-perfusion (Va/Q) ratio. Using a novel functional lung magnetic resonance imaging technique to measure regional Va/Q ratio, the gravitational gradients in proton density, ventilation, perfusion, and Va/Q ratio were measured in prone and supine posture. Data were acquired in seven healthy subjects in a single sagittal slice of the right lung at functional residual capacity. Regional specific ventilation images quantified using specific ventilation imaging and proton density images obtained using a fast gradient-echo sequence were registered and smoothed to calculate regional alveolar ventilation. Perfusion was measured using arterial spin labeling. Ventilation (ml·min(-1)·ml(-1)) images were combined on a voxel-by-voxel basis with smoothed perfusion (ml·min(-1)·ml(-1)) images to obtain regional Va/Q ratio. Data were averaged for voxels within 1-cm gravitational planes, starting from the most gravitationally dependent lung. The slope of the relationship between alveolar ventilation and vertical height was less prone than supine (-0.17 ± 0.10 ml·min(-1)·ml(-1)·cm(-1) supine, -0.040 ± 0.03 prone ml·min(-1)·ml(-1)·cm(-1), P = 0.02) as was the slope of the perfusion-height relationship (-0.14 ± 0.05 ml·min(-1)·ml(-1)·cm(-1) supine, -0.08 ± 0.09 prone ml·min(-1)·ml(-1)·cm(-1), P = 0.02). There was a significant gravitational gradient in Va/Q ratio in both postures (P < 0.05) that was less in prone (0.09 ± 0.08 cm(-1) supine, 0.04 ± 0.03 cm(-1) prone, P = 0.04). The gravitational gradients in ventilation, perfusion, and regional Va/Q ratio were greater supine than prone, suggesting an interplay between thoracic cavity configuration, airway and vascular tree anatomy, and the effects of gravity on Va/Q matching.

  11. The gravitational distribution of ventilation-perfusion ratio is more uniform in prone than supine posture in the normal human lung

    PubMed Central

    Sá, Rui Carlos; Theilmann, Rebecca J.; Buxton, Richard B.; Prisk, G. Kim; Hopkins, Susan R.

    2013-01-01

    The gravitational gradient of intrapleural pressure is suggested to be less in prone posture than supine. Thus the gravitational distribution of ventilation is expected to be more uniform prone, potentially affecting regional ventilation-perfusion (V̇a/Q̇) ratio. Using a novel functional lung magnetic resonance imaging technique to measure regional V̇a/Q̇ ratio, the gravitational gradients in proton density, ventilation, perfusion, and V̇a/Q̇ ratio were measured in prone and supine posture. Data were acquired in seven healthy subjects in a single sagittal slice of the right lung at functional residual capacity. Regional specific ventilation images quantified using specific ventilation imaging and proton density images obtained using a fast gradient-echo sequence were registered and smoothed to calculate regional alveolar ventilation. Perfusion was measured using arterial spin labeling. Ventilation (ml·min−1·ml−1) images were combined on a voxel-by-voxel basis with smoothed perfusion (ml·min−1·ml−1) images to obtain regional V̇a/Q̇ ratio. Data were averaged for voxels within 1-cm gravitational planes, starting from the most gravitationally dependent lung. The slope of the relationship between alveolar ventilation and vertical height was less prone than supine (−0.17 ± 0.10 ml·min−1·ml−1·cm−1 supine, −0.040 ± 0.03 prone ml·min−1·ml−1·cm−1, P = 0.02) as was the slope of the perfusion-height relationship (−0.14 ± 0.05 ml·min−1·ml−1·cm−1 supine, −0.08 ± 0.09 prone ml·min−1·ml−1·cm−1, P = 0.02). There was a significant gravitational gradient in V̇a/Q̇ ratio in both postures (P < 0.05) that was less in prone (0.09 ± 0.08 cm−1 supine, 0.04 ± 0.03 cm−1 prone, P = 0.04). The gravitational gradients in ventilation, perfusion, and regional V̇a/Q̇ ratio were greater supine than prone, suggesting an interplay between thoracic cavity configuration, airway and vascular tree anatomy, and the effects of

  12. Immunoadjuvant Therapy and Noninvasive Ventilation for Acute Respiratory Failure in Lung Tuberculosis: A Case Study

    PubMed Central

    Flores-Franco, René Agustín; Olivas-Medina, Dahyr Alberto; Pacheco-Tena, Cesar Francisco; Duque-Rodríguez, Jorge

    2015-01-01

    Acute respiratory failure caused by pulmonary tuberculosis is a rare event but with a high mortality even while receiving mechanical ventilatory support. We report the case of a young man with severe pulmonary tuberculosis refractory to conventional therapy who successfully overcame the critical period of his condition using noninvasive ventilation and immunoadjuvant therapy that included three doses of etanercept 25 mg subcutaneously. We conclude that the use of etanercept along with antituberculosis treatment appears to be safe and effective in patients with pulmonary tuberculosis presenting with acute respiratory failure. PMID:26273486

  13. Dependence of lung injury on inflation rate during low-volume ventilation in normal open-chest rabbits.

    PubMed

    D'Angelo, Edgardo; Pecchiari, Matteo; Saetta, Marina; Balestro, Elisabetta; Milic-Emili, Joseph

    2004-07-01

    Lung mechanics and morphometry were assessed in two groups of nine normal open-chest rabbits mechanically ventilated (MV) for 3-4 h at zero end-expiratory pressure (ZEEP) with physiological tidal volumes (Vt; 11 ml/kg) and high (group A) or low (group B) inflation flow (44 and 6.1 ml x kg(-1) x s(-1), respectively). Relative to initial MV on positive end-expiratory pressure (PEEP; 2.3 cmH(2)O), MV on ZEEP increased quasi-static elastance and airway and viscoelastic resistance more in group A (+251, +393, and +225%, respectively) than in group B (+180, +247, and +183%, respectively), with no change in viscoelastic time constant. After restoration of PEEP, quasi-static elastance and viscoelastic resistance returned to control, whereas airway resistance, still relative to initial values, remained elevated more in group A (+86%) than in group B (+33%). In contrast, prolonged high-flow MV on PEEP had no effect on lung mechanics of seven open-chest rabbits (group C). Gas exchange on PEEP was equally preserved in all groups, and the lung wet-to-dry ratios were normal. Relative to group C, both groups A and B had an increased percentage of abnormal alveolar-bronchiolar attachments and number of polymorphonuclear leukocytes in alveolar septa, the latter being significantly larger in group A than in group B. Thus prolonged MV on ZEEP with cyclic opening-closing of peripheral airways causes alveolar-bronchiolar uncoupling and parenchymal inflammation with concurrent, persistent increase in airway resistance, which are worsened by high-inflation flow.

  14. Efficacy of low tidal volume ventilation in patients with different clinical risk factors for acute lung injury and the acute respiratory distress syndrome.

    PubMed

    Eisner, M D; Thompson, T; Hudson, L D; Luce, J M; Hayden, D; Schoenfeld, D; Matthay, M A

    2001-07-15

    In patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), a recent ARDS Network randomized controlled trial demonstrated that a low tidal volume (VT) mechanical ventilation strategy (6 ml/kg) reduced mortality by 22% compared with traditional mechanical ventilation (12 ml/kg). In this study, we examined the relative efficacy of low VT mechanical ventilation among 902 patients with different clinical risk factors for ALI/ARDS who participated in ARDS Network randomized controlled trials. The clinical risk factor for ALI/ARDS was associated with substantial variation in mortality. The risk of death (before discharge home with unassisted breathing) was highest in patients with sepsis (43%); intermediate in subjects with pneumonia (36%), aspiration (37%), and other risk factors (35%); and lowest in those with trauma (11%) (p < 0.0001). Despite these differences in mortality, there was no evidence that the efficacy of the low VT strategy varied by clinical risk factor (p = 0.76, for interaction between ventilator group and risk factor). There was also no evidence of differential efficacy of low VT ventilation in the other study outcomes: proportion of patients achieving unassisted breathing (p = 0.59), ventilator-free days (p = 0.58), or development of nonpulmonary organ failure (p = 0.44). Controlling for demographic and clinical covariates did not appreciably affect these results. After reclassifying the clinical risk factors as pulmonary versus nonpulmonary predisposing conditions and infection-related versus non-infection-related conditions, there was still no evidence that the efficacy of low VT ventilation differed among clinical risk factor subgroups. In conclusion, we found no evidence that the efficacy of the low VT ventilation strategy differed among clinical risk factor subgroups for ALI/ARDS.

  15. Pulmonary rehabilitation coupled with negative pressure ventilation decreases decline in lung function, hospitalizations, and medical cost in COPD

    PubMed Central

    Huang, Hung-Yu; Chou, Pai-Chien; Joa, Wen-Ching; Chen, Li-Fei; Sheng, Te-Fang; Lin, Horng-Chyuan; Yang, Lan-Yan; Pan, Yu-Bin; Chung, Fu-Tsai; Wang, Chun-Hua; Kuo, Han-Pin

    2016-01-01

    Abstract Pulmonary rehabilitation (PR) brings benefits to patients with chronic obstructive pulmonary disease (COPD). Negative pressure ventilation (NPV) increases ventilation and decreases hyperinflation as well as breathing work in COPD. We evaluated the long-term effects of a hospital-based PR program coupled with NPV support in patients with COPD on clinical outcomes. One hundred twenty-nine patients with COPD were followed up for more than 5 years, with the NPV group (n = 63) receiving the support of NPV (20–30 cm H2O delivery pressure for 60 min) and unsupervised home exercise program of 20 to 30 min daily walk, while the control group (n = 6) only received unsupervised home exercise program. Pulmonary function tests and 6 min walk tests (6MWT) were performed every 3 to 6 months. Emergency room (ER) visits and hospitalization with medical costs were recorded. A significant time-by-group interaction in the yearly decline of forced expiratory volume in 1 s in the control group analyzed by mixed-model repeated-measure analysis was found (P = 0.048). The 6MWT distance of the NPV group was significantly increased during the first 4 years, with the interaction of time and group (P = 0.003), the time alone (P = 0.014), and the quadratic time (P < 0.001) being significant between the 2 groups. ER exacerbations and hospitalizations decreased by 66% (P < 0.0001) and 54% (P < 0.0001) in the NPV group, respectively. Patients on PR program coupled with NPV had a significant reduction of annual medical costs (P = 0.022). Our hospital-based multidisciplinary PR coupled with NPV reduced yearly decline of lung function, exacerbations, and hospitalization rates, and improved walking distance and medical costs in patients with COPD during a 5-year observation PMID:27741132

  16. Clinical challenges in mechanical ventilation.

    PubMed

    Goligher, Ewan C; Ferguson, Niall D; Brochard, Laurent J

    2016-04-30

    Mechanical ventilation supports gas exchange and alleviates the work of breathing when the respiratory muscles are overwhelmed by an acute pulmonary or systemic insult. Although mechanical ventilation is not generally considered a treatment for acute respiratory failure per se, ventilator management warrants close attention because inappropriate ventilation can result in injury to the lungs or respiratory muscles and worsen morbidity and mortality. Key clinical challenges include averting intubation in patients with respiratory failure with non-invasive techniques for respiratory support; delivering lung-protective ventilation to prevent ventilator-induced lung injury; maintaining adequate gas exchange in severely hypoxaemic patients; avoiding the development of ventilator-induced diaphragm dysfunction; and diagnosing and treating the many pathophysiological mechanisms that impair liberation from mechanical ventilation. Personalisation of mechanical ventilation based on individual physiological characteristics and responses to therapy can further improve outcomes. PMID:27203509

  17. Mitochondrial-targeted DNA repair enzyme 8-oxoguanine DNA glycosylase 1 protects against ventilator-induced lung injury in intact mice

    PubMed Central

    Hashizume, Masahiro; Mouner, Marc; Chouteau, Joshua M.; Gorodnya, Olena M.; Ruchko, Mykhaylo V.; Potter, Barry J.; Wilson, Glenn L.; Gillespie, Mark N.

    2013-01-01

    This study tested the hypothesis that oxidative mitochondrial-targeted DNA (mtDNA) damage triggered ventilator-induced lung injury (VILI). Control mice and mice infused with a fusion protein targeting the DNA repair enzyme, 8-oxoguanine-DNA glycosylase 1 (OGG1) to mitochondria were mechanically ventilated with a range of peak inflation pressures (PIP) for specified durations. In minimal VILI (1 h at 40 cmH2O PIP), lung total extravascular albumin space increased 2.8-fold even though neither lung wet/dry (W/D) weight ratios nor bronchoalveolar lavage (BAL) macrophage inflammatory protein (MIP)-2 or IL-6 failed to differ from nonventilated or low PIP controls. This increase in albumin space was attenuated by OGG1. Moderately severe VILI (2 h at 40 cmH2O PIP) produced a 25-fold increase in total extravascular albumin space, a 60% increase in W/D weight ratio and marked increases in BAL MIP-2 and IL-6, accompanied by oxidative mitochondrial DNA damage, as well as decreases in the total tissue glutathione (GSH) and GSH/GSSH ratio compared with nonventilated lungs. All of these injury indices were attenuated in OGG1-treated mice. At the highest level of VILI (2 h at 50 cmH2O PIP), OGG1 failed to protect against massive lung edema and BAL cytokines or against depletion of the tissue GSH pool. Interestingly, whereas untreated mice died before completing the 2-h protocol, OGG1-treated mice lived for the duration of observation. Thus mitochondrially targeted OGG1 prevented VILI over a range of ventilation times and pressures and enhanced survival in the most severely injured group. These findings support the concept that oxidative mtDNA damage caused by high PIP triggers induction of acute lung inflammation and injury. PMID:23241530

  18. Mitochondrial-targeted DNA repair enzyme 8-oxoguanine DNA glycosylase 1 protects against ventilator-induced lung injury in intact mice.

    PubMed

    Hashizume, Masahiro; Mouner, Marc; Chouteau, Joshua M; Gorodnya, Olena M; Ruchko, Mykhaylo V; Potter, Barry J; Wilson, Glenn L; Gillespie, Mark N; Parker, James C

    2013-02-15

    This study tested the hypothesis that oxidative mitochondrial-targeted DNA (mtDNA) damage triggered ventilator-induced lung injury (VILI). Control mice and mice infused with a fusion protein targeting the DNA repair enzyme, 8-oxoguanine-DNA glycosylase 1 (OGG1) to mitochondria were mechanically ventilated with a range of peak inflation pressures (PIP) for specified durations. In minimal VILI (1 h at 40 cmH(2)O PIP), lung total extravascular albumin space increased 2.8-fold even though neither lung wet/dry (W/D) weight ratios nor bronchoalveolar lavage (BAL) macrophage inflammatory protein (MIP)-2 or IL-6 failed to differ from nonventilated or low PIP controls. This increase in albumin space was attenuated by OGG1. Moderately severe VILI (2 h at 40 cmH(2)O PIP) produced a 25-fold increase in total extravascular albumin space, a 60% increase in W/D weight ratio and marked increases in BAL MIP-2 and IL-6, accompanied by oxidative mitochondrial DNA damage, as well as decreases in the total tissue glutathione (GSH) and GSH/GSSH ratio compared with nonventilated lungs. All of these injury indices were attenuated in OGG1-treated mice. At the highest level of VILI (2 h at 50 cmH(2)O PIP), OGG1 failed to protect against massive lung edema and BAL cytokines or against depletion of the tissue GSH pool. Interestingly, whereas untreated mice died before completing the 2-h protocol, OGG1-treated mice lived for the duration of observation. Thus mitochondrially targeted OGG1 prevented VILI over a range of ventilation times and pressures and enhanced survival in the most severely injured group. These findings support the concept that oxidative mtDNA damage caused by high PIP triggers induction of acute lung inflammation and injury.

  19. Mechanical Ventilation Augments Poly(I:C)-Induced Lung Injury via a WISP1-Integrin β3-Dependent Pathway in Mice

    PubMed Central

    Jin, Shuqing; Chen, Zhixia; Ding, Xibing; Zhao, Xiang; Jiang, Xi; Tong, Yao; Billiar, Timothy R; Li, Quan

    2016-01-01

    Mechanical ventilation can improve hypoxemia, but can also cause the so-called ventilator-induced lung injury (VILI). Polyinosinic:polycytidylic acid (poly(I:C)), an analogue of natural double-strand RNA virus, can induce lung inflammation. The purpose of this study was to determine whether moderate tidal volume mechanical ventilation (MTV) augments poly(I:C)-induced lung injury, and if so, the mechanism responsible for it. Two μg/g poly(I:C) were instilled intratracheally in C57BL/6J wide type (WT) mice. They were then randomized to MTV (10 ml/kg tidal volume) or spontaneous breathing. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected 4 h later for various measurements. Our results showed that MTV did not cause significant injury in normal lungs, but augmented poly(I:C)-induced lung injury. The expression level of WNT-induced secreted protein 1 (WISP1) was consistent with lung injury, and the amplification of lung injury by MTV could be alleviated by anti-WISP1 antibody treatment. MTV further increased poly(I:C)-induced integrin β3 expression in the lung. We performed coimmunoprecipitation, which showed there was an interaction between WISP1 and β3. WISP1 significantly increased poly(I:C)-induced TNF-α production in macrophages isolated from WT mice, but not in macrophages isolated from β3 knockout mice. Cotreatment with WISP1 and poly(I:C) markedly increased the phosphorylation of extracellular signal-related kinase (ERK) in macrophages. Pretreating macrophages with an ERK inhibitor, U0126, dose-dependently antagonized the synergistic effect of WISP1 on poly(I:C)-induced TNF-α release. In conclusion, MTV exaggerates poly(I:C)-induced lung injury in a WISP1- and integrin β3-dependent manner, involving, at least in part, the activation of the ERK pathway. The WISP1-integrin β3 pathway could be a novel therapeutic target. PMID:26772774

  20. Maintaining end-expiratory transpulmonary pressure prevents worsening of ventilator-induced lung injury caused by chest wall constriction in surfactant-depleted rats

    PubMed Central

    Loring, Stephen H.; Pecchiari, Matteo; Valle, Patrizia Della; Monaco, Ario; Gentile, Guendalina; D'Angelo, Edgardo

    2014-01-01

    Objective To see whether in acute lung injury (ALI) 1) compression of the lungs caused by thoracoabdominal constriction degrades lung function and worsens ventilator-induced lung injury (VILI), and 2) maintaining end-expiratory transpulmonary pressure (Pl) by increasing positive end-expiratory pressure (PEEP) reduces the deleterious effects of chest wall constriction. Design Experimental study in rats. Setting Physiology laboratory. Interventions ALI was induced in 3 groups of 9 rats by saline lavage. Nine animals immediately sacrificed served as control group. Group L had lavage only, group LC had the chest wall constricted with an elastic binder, and group LCP had the same chest constriction but with PEEP raised to maintain end-expiratory Pl. After lavage, all groups were ventilated with the same pattern for 1½ hr. Measurements and Main Results Pl, measured with an esophageal balloon-catheter, lung volume changes, arterial blood gasses and pH were assessed during mechanical ventilation (MV). Lung wet-to-dry ratio (W/D), albumin, TNF-α, IL-1β, IL-6, IL-10, and MIP-2 in serum and bronchoalveolar lavage fluid (BALF), and serum E-selectin and von Willebrand Factor (vWF) were measured at the end of MV. Lavage caused hypoxemia and acidemia, increased lung resistance and elastance, and decreased end-expiratory lung volume. With prolonged MV, lung mechanics, hypoxemia, and W/D were significantly worse in group LC. Pro-inflammatory cytokines except E-selectin were elevated in serum and BALF in all groups, with significantly greater levels of TNF-α, IL-1β, and IL-6 in group LC, which also exhibited significantly worse bronchiolar injury and greater heterogeneity of airspace expansion at a fixed Pl than other groups. Conclusions Chest wall constriction in ALI reduces lung volume, worsens hypoxemia, and increases pulmonary edema, mechanical abnormalities, pro-inflammatory mediator release, and histological signs of VILI. Maintaining end-expiratory Pl at preconstriction

  1. Ventilation-perfusion inequality in the human lung is not increased following no-decompression-stop hyperbaric exposure.

    PubMed

    Moore, Gaea Schwaebe; Wong, Stewart C; Darquenne, Chantal; Neuman, Tom S; West, John B; Kim Prisk, G

    2009-11-01

    Venous gas bubbles occur in recreational SCUBA divers in the absence of decompression sickness, forming venous gas emboli (VGE) which are trapped within pulmonary circulation and cleared by the lung without overt pathology. We hypothesized that asymptomatic VGE would transiently increase ventilation-perfusion mismatch due to their occlusive effects within the pulmonary circulation. Two sets of healthy volunteers (n = 11, n = 12) were recruited to test this hypothesis with a single recreational ocean dive or a baro-equivalent dry hyperbaric dive. Pulmonary studies (intrabreath V (A)/Q (iV/Q), alveolar dead space, and FVC) were conducted at baseline and repeat 1- and 24-h after the exposure. Contrary to our hypothesis V (A)/Q mismatch was decreased 1-h post-SCUBA dive (iV/Q slope 0.023 +/- 0.008 ml(-1) at baseline vs. 0.010 +/- 0.005 NS), and was significantly reduced 24-h post-SCUBA dive (0.000 +/- 0.005, p < 0.05), with improved V (A)/Q homogeneity inversely correlated to dive severity. No changes in V (A)/Q mismatch were observed after the chamber dive. Alveolar dead space decreased 24-h post-SCUBA dive (78 +/- 10 ml at baseline vs. 56 +/- 5, p < 0.05), but not 1-h post dive. FVC rose 1-h post-SCUBA dive (5.01 +/- 0.18 l vs. 5.21 +/- 0.26, p < 0.05), remained elevated 24-h post SCUBA dive (5.06 +/- 0.2, p < 0.05), but was decreased 1-hr after the chamber dive (4.96 +/- 0.31 L to 4.87 +/- 0.32, p < 0.05). The degree of V (A)/Q mismatch in the lung was decreased following recreational ocean dives, and was unchanged following an equivalent air chamber dive, arguing against an impact of VGE on the pulmonary circulation.

  2. [Intermittent forced ventilation of the lungs with series "PO" IVL apparatus].

    PubMed

    Khorokhordin, N E; Leonov, G N; Vasil'ev, A V; Kotras, R L; Prokof'eva, E N

    2004-01-01

    The authors suppose that the intermittent ventilation (IMV) may be provided by the connection of an additional respiratory appliance made on the basis of a standard narcosis attachment of "Polynarcon" type with a respirator "PO" and the patient. A specific feature of this modified respiratory appliance is the bellows which fulfiles the function of a reserved capacity for a breath and a damper when in the smoothed out (hung up) state. The intubation tube is fastened to the T-joint adapter of the narcosis attachment (the scheme is shown), the hose being detached from the expiration valve and connected with the respirator T-joint adapter (to the place of the intubation tube). On the termination of the forced breath the patient can (if he has enough force to open the expiration valve) fulfill a self-dependent breath from the additional respiration appliance (the expiration is fulfilled into the respirator as during the forced breath). A method of realization of IMV in the "PO" type respirators which have been produced in lots by the "Krasnogvardeets" firm since 2000-2002 is described.

  3. Novel method for conscious airway resistance and ventilation estimation in neonatal rodents using plethysmography and a mechanical lung.

    PubMed

    Zhang, Boyang; McDonald, Fiona B; Cummings, Kevin J; Frappell, Peter B; Wilson, Richard J A

    2014-09-15

    In unrestrained whole body plethysmography, tidal volume is commonly determined using the barometric method, which assumes that temperature and humidity changes (the 'barometric component') are solely responsible for breathing-related chamber pressure fluctuations. However, in small animals chamber pressure is also influenced by a 'mechanical component' dependent on airway resistance and airflow. We devised a novel 'mechanical lung' capable of simulating neonatal mouse breathing in the absence of temperature or humidity changes. Using this device, we confirm that the chamber pressure fluctuations produced by breathing of neonatal mice are dominated by the mechanical component, precluding direct quantitative assessment of tidal volume. Recognizing the importance of airway resistance to the chamber pressure signal and the ability of our device to simulate neonatal breathing at different frequencies and tidal volumes, we invented a novel in vivo, non-invasive method for conscious airway resistance and ventilation estimation (CARVE) in neonatal rodents. This technique will allow evaluation of developmental, pathological and pharmaceutical effects on airway resistance.

  4. Stroke volume variation fail to predict fluid responsiveness in patients undergoing pulmonary lobectomy with one-lung ventilation using thoracotomy.

    PubMed

    Fu, Qiang; Zhao, Feng; Mi, Weidong; Zhang, Hong

    2014-02-01

    The purpose of this study was to investigate the ability of stroke volume variation (SVV) to predict fluid responsiveness in patients undergoing pulmonary lobectomy with one lung ventilation (OLV). Thirty patients intubated with double-lumen tube were scheduled for a pulmonary lobectomy requiring OLV for at least 1 hour under general anesthesia. Hemodynamic variables including heart rate, mean arterial pressure, cardiac index (CI), stroke volume index (SVI), central venous pressure (CVP) and SVV were measured before and after volume expansion (VE) (8 mL/kg of 6% hydroxyethyl starch). Fluid responsiveness was defined as an increase in CI ≥ 10% after VE. Of the 30 patients, 16 (53%) were responders and 14 (47%) were nonresponders to intravascular VE. There were significant increases of CI, SVI in responders after VE (p < 0.01), but there were no significant changes in SVV in responders and nonresponders (p > 0.05). The baseline value of SVV, CVP, CI and SVI did not correlate significantly with ΔCI (p > 0.05). The area under the Receiver Operating Characteristic (ROC) curve were 0.507 for SVV (95% confidence interval, 0.294-0.720) and 0.556 for CVP (95% confidence interval, 0.339-0.773), neither was able to predict fluid responsiveness with sufficient statistical power. SVV measured by the Vigileo-FloTrac system was not able to predict fluid responsiveness in patients undergoing pulmonary lobectomy with OLV after thoractomy.

  5. Novel method for conscious airway resistance and ventilation estimation in neonatal rodents using plethysmography and a mechanical lung.

    PubMed

    Zhang, Boyang; McDonald, Fiona B; Cummings, Kevin J; Frappell, Peter B; Wilson, Richard J A

    2014-09-15

    In unrestrained whole body plethysmography, tidal volume is commonly determined using the barometric method, which assumes that temperature and humidity changes (the 'barometric component') are solely responsible for breathing-related chamber pressure fluctuations. However, in small animals chamber pressure is also influenced by a 'mechanical component' dependent on airway resistance and airflow. We devised a novel 'mechanical lung' capable of simulating neonatal mouse breathing in the absence of temperature or humidity changes. Using this device, we confirm that the chamber pressure fluctuations produced by breathing of neonatal mice are dominated by the mechanical component, precluding direct quantitative assessment of tidal volume. Recognizing the importance of airway resistance to the chamber pressure signal and the ability of our device to simulate neonatal breathing at different frequencies and tidal volumes, we invented a novel in vivo, non-invasive method for conscious airway resistance and ventilation estimation (CARVE) in neonatal rodents. This technique will allow evaluation of developmental, pathological and pharmaceutical effects on airway resistance. PMID:25017785

  6. Continuous quantitative measurement of the proximal airway dimensions and lung density on four-dimensional dynamic-ventilation CT in smokers

    PubMed Central

    Yamashiro, Tsuneo; Moriya, Hiroshi; Tsubakimoto, Maho; Matsuoka, Shin; Murayama, Sadayuki

    2016-01-01

    Purpose Four-dimensional dynamic-ventilation computed tomography (CT) imaging demonstrates continuous movement of the airways and lungs, which cannot be depicted with conventional CT. We aimed to investigate continuous changes in lung density and airway dimensions and to assess the correlation with spirometric values in smokers. Materials and methods This retrospective study was approved by the Institutional Review Board, and informed consent was waived. Twenty-one smokers including six patients with COPD underwent four-dimensional dynamic-ventilation CT during free breathing (160 mm in length). The mean lung density (MLD) of the scanned lung and luminal areas (Ai) of fixed points in the trachea and the right proximal bronchi (main bronchus, upper bronchus, bronchus intermedius, and lower bronchus) were continuously measured. Concordance between the time curve of the MLD and that of the airway Ai values was expressed by cross-correlation coefficients. The associations between these quantitative measurements and the forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) values were assessed by Spearman’s rank correlation analysis. Results On the time curve for the MLD, the Δ-MLD1.05 values between the peak inspiratory frame to the later third frame (1.05 seconds later) were strongly correlated with the FEV1/FVC (ρ=0.76, P<0.0001). The cross-correlation coefficients between the airway Ai and MLD values were significantly correlated with the FEV1/FVC (ρ=−0.56 to −0.66, P<0.01), except for the right upper bronchus. This suggested that the synchrony between the airway and lung movement was lost in patients with severe airflow limitation. Conclusion Respiratory changes in the MLD and synchrony between the airway Ai and the MLD measured with dynamic-ventilation CT were correlated with patient’s spirometric values. PMID:27110108

  7. Hydrogen inhalation reduced epithelial apoptosis in ventilator-induced lung injury via a mechanism involving nuclear factor-kappa B activation

    SciTech Connect

    Huang, Chien-Sheng; Kawamura, Tomohiro; Peng, Ximei; Tochigi, Naobumi; Shigemura, Norihisa; Billiar, Timothy R.; Nakao, Atsunori; Toyoda, Yoshiya

    2011-05-06

    Highlights: {yields} Hydrogen is a regulatory molecule with antiinflammatory and antiapoptotic protective effects. {yields} There is very limited information on the pathways regulated in vivo by the hydrogen. {yields} Antiapoptotic abilities of hydrogen were explained by upregulation of the antiapoptotic gene. {yields} NF{kappa}B activation during hydrogen treatment was correlated with elevated antiapoptotic protein. {yields} NF{kappa}B activation associated with increase Bcl-2 may contribute to cytoprotection of hydrogen. -- Abstract: We recently demonstrated the inhalation of hydrogen gas, a novel medical therapeutic gas, ameliorates ventilator-induced lung injury (VILI); however, the molecular mechanisms by which hydrogen ameliorates VILI remain unclear. Therefore, we investigated whether inhaled hydrogen gas modulates the nuclear factor-kappa B (NF{kappa}B) signaling pathway. VILI was generated in male C57BL6 mice by performing a tracheostomy and placing the mice on a mechanical ventilator (tidal volume of 30 ml/kg or 10 ml/kg without positive end-expiratory pressure). The ventilator delivered either 2% nitrogen or 2% hydrogen in balanced air. NF{kappa}B activation, as indicated by NF{kappa}B DNA binding, was detected by electrophoretic mobility shift assays and enzyme-linked immunosorbent assay. Hydrogen gas inhalation increased NF{kappa}B DNA binding after 1 h of ventilation and decreased NF{kappa}B DNA binding after 2 h of ventilation, as compared with controls. The early activation of NF{kappa}B during hydrogen treatment was correlated with elevated levels of the antiapoptotic protein Bcl-2 and decreased levels of Bax. Hydrogen inhalation increased oxygen tension, decreased lung edema, and decreased the expression of proinflammatory mediators. Chemical inhibition of early NF{kappa}B activation using SN50 reversed these protective effects. NF{kappa}B activation and an associated increase in the expression of Bcl-2 may contribute, in part, to the

  8. Correlation among regional ventilation, airway resistance and particle deposition in normal and severe asthmatic lungs

    NASA Astrophysics Data System (ADS)

    Choi, Sanghun; Hoffman, Eric A.; Tawhai, Merryn H.; Lin, Ching-Long

    2012-11-01

    Computational fluid dynamic simulations are performed to investigate flow characteristics and quantify particle deposition with normal and severe asthmatic lungs. Continuity and Navier-Stokes equations are solved with unstructured meshes and finite element method; a large eddy simulation model is adopted to capture turbulent and/or transitional flows created in the glottis. The human airway models are reconstructed from CT volumetric images, and the subject-specific boundary condition is imposed to the 3D ending branches with the aid of an image registration technique. As a result, several constricted airways are captured in CT images of severe asthmatic subjects, causing significant pressure drop with high air speed because the constriction of airways creates high flow resistance. The simulated instantaneous velocity fields obtained are then employed to track transport and deposition of 2.5 μm particles. It is found that high flow resistance regions are correlated with high particle-deposition regions. In other words, the constricted airways can induce high airway resistance and subsequently increase particle deposition in the regions. This result may be applied to understand the characteristics of deposition of pharmaceutical aerosols or bacteria. This work was supported in part by NIH grants R01-HL094315 and S10-RR022421.

  9. Effect of Pressure Controlled Waveforms on Flow Transport and Gas mixing in a Patient Specific Lung Model during Invasive High Frequency Oscillatory Ventilation

    NASA Astrophysics Data System (ADS)

    Alzahrany, Mohammed; Banerjee, Arindam

    2012-11-01

    A computational fluid dynamic study is carried out to investigate gas transport in patient specific human lung models (based on CT scans) during high frequency oscillatory ventilation (HFOV). Different pressure-controlled waveforms and various ventilator frequencies are studied to understand the effect of flow transport and gas mixing during these processes. Three different pressure waveforms are created by solving the equation of motion subjected to constant lung wall compliance and flow resistance. Sinusoidal, exponential and constant waveforms shapes are considered with three different frequencies 6, 10 and 15 Hz and constant tidal volume 50 ml. The velocities are calculated from the obtained flow rate and imposed as inlet flow conditions to represent the mechanical ventilation waveforms. An endotracheal tube ETT is joined to the model to account for the effect of the invasive management device with the peak Reynolds number (Re) for all the cases ranging from 6960 to 24694. All simulations are performed using high order LES turbulent model. The gas transport near the flow reversal will be discussed at different cycle phases for all the cases and a comparison of the secondary flow structures between different cases will be presented.

  10. Effect of salmeterol/fluticasone combination on the dynamic changes of lung mechanics in mechanically ventilated COPD patients: a prospective pilot study

    PubMed Central

    Chen, Wei-Chih; Chen, Hung-Hsing; Chiang, Chi-Huei; Lee, Yu-Chin; Yang, Kuang-Yao

    2016-01-01

    Background The combined therapy of inhaled corticosteroids and long-acting beta-2 agonists for mechanically ventilated patients with COPD has never been explored. Therefore, the aim of this study was to investigate their dynamic effects on lung mechanics and gas exchange. Materials and methods Ten mechanically ventilated patients with resolution of the causes of acute exacerbations of COPD were included. Four puffs of salmeterol 25 μg/fluticasone 125 μg combination therapy were administered. Lung mechanics, including maximum resistance of the respiratory system (Rrs), end-inspiratory static compliance, peak inspiratory pressure (PIP), plateau pressure, and mean airway pressure along with gas exchange function were measured and analyzed. Results Salmeterol/fluticasone produced a significant improvement in Rrs and PIP after 30 minutes. With regard to changes in baseline values, salmeterol/fluticasone inhalation had a greater effect on PIP than Rrs. However, the therapeutic effects seemed to lose significance after 3 hours of inhaled corticosteroid/long-acting beta-2 agonist administration. Conclusion The combination of salmeterol/fluticasone-inhaled therapy in mechanically ventilated patients with COPD had a significant benefit in reducing Rrs and PIP. PMID:26869782

  11. An evaluation of the relative efficacy of an open airway, an oxygen reservoir and continuous positive airway pressure 5 cmH2O on the non-ventilated lung.

    PubMed

    Slimani, J; Russell, W J; Jurisevic, C

    2004-12-01

    The aim of this study, during one-lung ventilation, was to evaluate if oxygenation could be improved by use of a simple oxygen reservoir or application of 5 cmH2O continuous positive airway pressure (CPAP) to the non-ventilated lung compared with an open airway. Twenty-three patients with lung malignancy, undergoing thoracotomy requiring at least 60 minutes of one-lung ventilation before lung lobe excision, were studied. After routine induction and establishment of one-lung ventilation, the three treatments were applied in turn to the same patient in a sequence selected randomly. The first treatment was repeated as a fourth treatment and these results of the repeated treatment averaged to minimize the effect of slow changes. Arterial oxygenation was measured by an arterial blood gas 15 minutes after the application of each treatment. Twenty patients completed the study. Mean PaO2 (in mmHg) was 210.3 (SD 105.5) in the "OPEN" treatment, 186.0 (SD 109.2) in the "RESERVOIR" treatment, and 240.5 (SD 116.0) in the "CPAP" treatment. This overall difference was not quite significant (P = 0.058, paired ANOVA), but comparison of the pairs showed that there was a significant better oxygenation only with the CPAP compared to the reservoir treatments (t = 2.52, P = 0.021). While the effect on the surgical field was not apparent in most patients, in one patient surgery was impeded during CPAP. Our results show that the use of a reservoir does not give oxygenation better than an open tube, and is less effective than the use of CPAP 5 cmH2O on the non-ventilated lung during one-lung ventilation.

  12. Lung Function and Incidence of Chronic Obstructive Pulmonary Disease after Improved Cooking Fuels and Kitchen Ventilation: A 9-Year Prospective Cohort Study

    PubMed Central

    Zhou, Yumin; Zou, Yimin; Li, Xiaochen; Chen, Shuyun; Zhao, Zhuxiang; He, Fang; Zou, Weifeng; Luo, Qiuping; Li, Wenxi; Pan, Yiling; Deng, Xiaoliang; Wang, Xiaoping; Qiu, Rong; Liu, Shiliang; Zheng, Jingping; Zhong, Nanshan; Ran, Pixin

    2014-01-01

    Background Biomass smoke is associated with the risk of chronic obstructive pulmonary disease (COPD), but few studies have elaborated approaches to reduce the risk of COPD from biomass burning. The purpose of this study was to determine whether improved cooking fuels and ventilation have effects on pulmonary function and the incidence of COPD. Methods and Findings A 9-y prospective cohort study was conducted among 996 eligible participants aged at least 40 y from November 1, 2002, through November 30, 2011, in 12 villages in southern China. Interventions were implemented starting in 2002 to improve kitchen ventilation (by providing support and instruction for improving biomass stoves or installing exhaust fans) and to promote the use of clean fuels (i.e., biogas) instead of biomass for cooking (by providing support and instruction for installing household biogas digesters); questionnaire interviews and spirometry tests were performed in 2005, 2008, and 2011. That the interventions improved air quality was confirmed via measurements of indoor air pollutants (i.e., SO2, CO, CO2, NO2, and particulate matter with an aerodynamic diameter of 10 µm or less) in a randomly selected subset of the participants' homes. Annual declines in lung function and COPD incidence were compared between those who took up one, both, or neither of the interventions. Use of clean fuels and improved ventilation were associated with a reduced decline in forced expiratory volume in 1 s (FEV1): decline in FEV1 was reduced by 12 ml/y (95% CI, 4 to 20 ml/y) and 13 ml/y (95% CI, 4 to 23 ml/y) in those who used clean fuels and improved ventilation, respectively, compared to those who took up neither intervention, after adjustment for confounders. The combined improvements of use of clean fuels and improved ventilation had the greatest favorable effects on the decline in FEV1, with a slowing of 16 ml/y (95% CI, 9 to 23 ml/y). The longer the duration of improved fuel use and ventilation, the greater

  13. Ventilation and ventilators.

    PubMed

    Hayes, B

    1982-01-01

    The history of ventilation is reviewed briefly and recent developments in techniques of ventilation are discussed. Operating features of ventilators have changed in the past few years, partly as the result of clinical progress; yet, technology appears to have outstripped the clinician's ability to harness it most effectively. Clinical discipline and training of medical staff in the use of ventilators could be improved. The future is promising if clinician and designer can work together closely. Ergonomics of ventilators and their controls and the provision of alarms need special attention. Microprocessors are likely to feature prominently in the next generation of designs.

  14. Ventilation and ventilators.

    PubMed

    Hayes, B

    1982-01-01

    The history of ventilation is reviewed briefly and recent developments in techniques of ventilation are discussed. Operating features of ventilators have changed in the past few years, partly as the result of clinical progress; yet, technology appears to have outstripped the clinician's ability to harness it most effectively. Clinical discipline and training of medical staff in the use of ventilators could be improved. The future is promising if clinician and designer can work together closely. Ergonomics of ventilators and their controls and the provision of alarms need special attention. Microprocessors are likely to feature prominently in the next generation of designs. PMID:6754938

  15. Update on Nonsurgical Lung Volume Reduction Procedures.

    PubMed

    Neder, J Alberto; O'Donnell, Denis E

    2016-01-01

    There has been a surge of interest in endoscopic lung volume reduction (ELVR) strategies for advanced COPD. Valve implants, coil implants, biological LVR (BioLVR), bronchial thermal vapour ablation, and airway stents are used to induce lung deflation with the ultimate goal of improving respiratory mechanics and chronic dyspnea. Patients presenting with severe air trapping (e.g., inspiratory capacity/total lung capacity (TLC) < 25%, residual volume > 225% predicted) and thoracic hyperinflation (TLC > 150% predicted) have the greatest potential to derive benefit from ELVR procedures. Pre-LVRS or ELVR assessment should ideally include cardiological evaluation, high resolution CT scan, ventilation and perfusion scintigraphy, full pulmonary function tests, and cardiopulmonary exercise testing. ELVR procedures are currently available in selected Canadian research centers as part of ethically approved clinical trials. If a decision is made to offer an ELVR procedure, one-way valves are the first option in the presence of complete lobar exclusion and no significant collateral ventilation. When the fissure is not complete, when collateral ventilation is evident in heterogeneous emphysema or when emphysema is homogeneous, coil implants or BioLVR (in that order) are the next logical alternatives. PMID:27445557

  16. Update on Nonsurgical Lung Volume Reduction Procedures

    PubMed Central

    Neder, J. Alberto; O'Donnell, Denis E.

    2016-01-01

    There has been a surge of interest in endoscopic lung volume reduction (ELVR) strategies for advanced COPD. Valve implants, coil implants, biological LVR (BioLVR), bronchial thermal vapour ablation, and airway stents are used to induce lung deflation with the ultimate goal of improving respiratory mechanics and chronic dyspnea. Patients presenting with severe air trapping (e.g., inspiratory capacity/total lung capacity (TLC) < 25%, residual volume > 225% predicted) and thoracic hyperinflation (TLC > 150% predicted) have the greatest potential to derive benefit from ELVR procedures. Pre-LVRS or ELVR assessment should ideally include cardiological evaluation, high resolution CT scan, ventilation and perfusion scintigraphy, full pulmonary function tests, and cardiopulmonary exercise testing. ELVR procedures are currently available in selected Canadian research centers as part of ethically approved clinical trials. If a decision is made to offer an ELVR procedure, one-way valves are the first option in the presence of complete lobar exclusion and no significant collateral ventilation. When the fissure is not complete, when collateral ventilation is evident in heterogeneous emphysema or when emphysema is homogeneous, coil implants or BioLVR (in that order) are the next logical alternatives. PMID:27445557

  17. [Successful One-lung Ventilation with a Right-sided Double-lumen Tube in a Patient with a Right Upper Tracheal Bronchus, who Underwent Left Pneumonectomy for Left Hilar Lung Cancer].

    PubMed

    Kawagoe, Izumi; Kohchiyama, Tsukasa; Hayashida, Masakazu; Satoh, Daizoh; Suzuki, Kenji; Inada, Eiichi

    2016-06-01

    A 60-year-old male patient with left hilar lung cancer was scheduled to undergo left pneumonectomy or left sleeve lower lobectomy. Preoperative computer tomographic and bronchoscopic examinations revealed that the bronchus (B1) to the right apical segment (S1) was a tracheal bronchus (TB) originating from the trachea approximately 10 mm above the carina. Because the left main bronchus was to be dissected, a right-sided double-lumen tube (DLT) was selected to completely protect the right lung from spillage of secretions or cancer cells from the left lung. The right-sided DLT was placed so as to fit its lateral opening of the bronchial lumen to normal upper branches (B2, B3), while sacrificing ventilation of S1 with an abnormal branch (B1). However, one-lung ventilation (OLV) of the right lung could not be achieved, since a gas leakage from the opened tracheal lumen occurred, most probably due to intra-lobar micro-airway communications between S1 and S2/S3. The DLT was withdrawn until the blue bronchial cuff occluded the orifice of the TB (B1). Although the upper half of the blue bronchial cuff appeared above the tracheal carina, OLV through the two bronchial lumen openings could be achieved due to a specific, slanted doughnut shape of the blue bronchial cuff and the location of the abnormal branch (B1) approximate to the carina. Left pneumonectomy using successful OLV was completed safely without hypoxemia or hypercapnea. Our experience indicates that management of OLV for patients with a thoracheal bronchus needs special considerations of the exact location of the TB and intra-lobar micro-airway communications, in addition to types of scheduled surgical procedures. PMID:27483653

  18. Mid-ventilation CT scan construction from four-dimensional respiration-correlated CT scans for radiotherapy planning of lung cancer patients

    SciTech Connect

    Wolthaus, Jochem; Schneider, Christoph; Sonke, Jan-Jakob; Herk, Marcel van; Belderbos, Jose; Rossi, Maddalena; Lebesque, Joos V.; Damen, Eugene M.F. . E-mail: e.damen@nki.nl

    2006-08-01

    Purpose: Four-dimensional (4D) respiration-correlated imaging techniques can be used to obtain (respiration) artifact-free computed tomography (CT) images of the thorax. Current radiotherapy planning systems, however, do not accommodate 4D-CT data. The purpose of this study was to develop a simple, new concept to incorporate patient-specific motion information, using 4D-CT scans, in the radiotherapy planning process of lung cancer patients to enable smaller error margins. Methods and Materials: A single CT scan was selected from the 4D-CT data set. This scan represented the tumor in its time-averaged position over the respiratory cycle (the mid-ventilation CT scan). To select the appropriate CT scan, two methods were used. First, the three-dimensional tumor motion was analyzed semiautomatically to calculate the mean tumor position and the corresponding respiration phase. An alternative automated method was developed to select the correct CT scan using the diaphragm motion. Results: Owing to hysteresis, mid-ventilation selection using the three-dimensional tumor motion had a tumor position accuracy (with respect to the mean tumor position) better than 1.1 {+-} 1.1 mm for all three directions (inhalation and exhalation). The accuracy in the diaphragm motion method was better than 1.1 {+-} 1.1 mm. Conventional free-breathing CT scanning had an accuracy better than 0 {+-} 3.9 mm. The mid-ventilation concept can result in an average irradiated volume reduction of 20% for tumors with a diameter of 40 mm. Conclusion: Tumor motion and the diaphragm motion method can be used to select the (artifact-free) mid-ventilation CT scan, enabling a significant reduction of the irradiated volume.

  19. Renal scintigraphy in veterinary medicine.

    PubMed

    Tyson, Reid; Daniel, Gregory B

    2014-01-01

    Renal scintigraphy is performed commonly in dogs and cats and has been used in a variety of other species. In a 2012 survey of the members of the Society of Veterinary Nuclear Medicine, 95% of the respondents indicated they perform renal scintigraphy in their practice. Renal scintigraphy is primarily used to assess renal function and to evaluate postrenal obstruction. This article reviews how renal scintigraphy is used in veterinary medicine and describes the methods of analysis. Species variation is also discussed.

  20. Comparison between radioactive aerosol, technegas and krypton for ventilation imaging in healthy calves.

    PubMed

    Coghe, J; Votion, D; Lekeux, P

    2000-07-01

    The use of lung scintigraphy in calves necessitates the validation of a ventilation (V) imaging agent compatible with clinical applications. This study aimed at defining the value of an inhaled radioactive aerosol (99mTc-DTPA) and a 'pseudogas' (Technegas) in the assessment of regional V in healthy conscious calves by comparing 99mTc-DTPA and Technegas deposition (D) images to V(V) images obtained from the steady-state inhalation of the short half-life krypton 81 (81mKr) gas. Images were compared by analysis of radioactivity distribution in computer-generated regions of interest within the right lung and D to V ratio images were generated in order to highlight areas of mismatching between 99mTc-DTPA or Technegas and 81mKr distributions. Results of this analysis showed that the 99mTc-DTPA aerosol droplets were unable to reach the lung parenchyma because of significant particle impaction in the major conducting airways. Better definition of the ventilated lung was obtained when using Technegas because of minimal deposition in conducting airways. Furthermore, the Technegas and 81mKr distribution patterns were highly equivalent.

  1. Monitoring of intratidal lung mechanics: a Graphical User Interface for a model-based decision support system for PEEP-titration in mechanical ventilation.

    PubMed

    Buehler, S; Lozano-Zahonero, S; Schumann, S; Guttmann, J

    2014-12-01

    In mechanical ventilation, a careful setting of the ventilation parameters in accordance with the current individual state of the lung is crucial to minimize ventilator induced lung injury. Positive end-expiratory pressure (PEEP) has to be set to prevent collapse of the alveoli, however at the same time overdistension should be avoided. Classic approaches of analyzing static respiratory system mechanics fail in particular if lung injury already prevails. A new approach of analyzing dynamic respiratory system mechanics to set PEEP uses the intratidal, volume-dependent compliance which is believed to stay relatively constant during one breath only if neither atelectasis nor overdistension occurs. To test the success of this dynamic approach systematically at bedside or in an animal study, automation of the computing steps is necessary. A decision support system for optimizing PEEP in form of a Graphical User Interface (GUI) was targeted. Respiratory system mechanics were analyzed using the gliding SLICE method. The resulting shapes of the intratidal compliance-volume curve were classified into one of six categories, each associated with a PEEP-suggestion. The GUI should include a graphical representation of the results as well as a quality check to judge the reliability of the suggestion. The implementation of a user-friendly GUI was successfully realized. The agreement between modelled and measured pressure data [expressed as root-mean-square (RMS)] tested during the implementation phase with real respiratory data from two patient studies was below 0.2 mbar for data taken in volume controlled mode and below 0.4 mbar for data taken in pressure controlled mode except for two cases with RMS < 0.6 mbar. Visual inspections showed, that good and medium quality data could be reliably identified. The new GUI allows visualization of intratidal compliance-volume curves on a breath-by-breath basis. The automatic categorisation of curve shape into one of six shape

  2. Monitoring of intratidal lung mechanics: a Graphical User Interface for a model-based decision support system for PEEP-titration in mechanical ventilation.

    PubMed

    Buehler, S; Lozano-Zahonero, S; Schumann, S; Guttmann, J

    2014-12-01

    In mechanical ventilation, a careful setting of the ventilation parameters in accordance with the current individual state of the lung is crucial to minimize ventilator induced lung injury. Positive end-expiratory pressure (PEEP) has to be set to prevent collapse of the alveoli, however at the same time overdistension should be avoided. Classic approaches of analyzing static respiratory system mechanics fail in particular if lung injury already prevails. A new approach of analyzing dynamic respiratory system mechanics to set PEEP uses the intratidal, volume-dependent compliance which is believed to stay relatively constant during one breath only if neither atelectasis nor overdistension occurs. To test the success of this dynamic approach systematically at bedside or in an animal study, automation of the computing steps is necessary. A decision support system for optimizing PEEP in form of a Graphical User Interface (GUI) was targeted. Respiratory system mechanics were analyzed using the gliding SLICE method. The resulting shapes of the intratidal compliance-volume curve were classified into one of six categories, each associated with a PEEP-suggestion. The GUI should include a graphical representation of the results as well as a quality check to judge the reliability of the suggestion. The implementation of a user-friendly GUI was successfully realized. The agreement between modelled and measured pressure data [expressed as root-mean-square (RMS)] tested during the implementation phase with real respiratory data from two patient studies was below 0.2 mbar for data taken in volume controlled mode and below 0.4 mbar for data taken in pressure controlled mode except for two cases with RMS < 0.6 mbar. Visual inspections showed, that good and medium quality data could be reliably identified. The new GUI allows visualization of intratidal compliance-volume curves on a breath-by-breath basis. The automatic categorisation of curve shape into one of six shape

  3. Noninvasive ventilation in trauma

    PubMed Central

    Karcz, Marcin K; Papadakos, Peter J

    2015-01-01

    Trauma patients are a diverse population with heterogeneous needs for ventilatory support. This requirement depends mainly on the severity of their ventilatory dysfunction, degree of deterioration in gaseous exchange, any associated injuries, and the individual feasibility of potentially using a noninvasive ventilation approach. Noninvasive ventilation may reduce the need to intubate patients with trauma-related hypoxemia. It is well-known that these patients are at increased risk to develop hypoxemic respiratory failure which may or may not be associated with hypercapnia. Hypoxemia in these patients is due to ventilation perfusion mismatching and right to left shunt because of lung contusion, atelectasis, an inability to clear secretions as well as pneumothorax and/or hemothorax, all of which are common in trauma patients. Noninvasive ventilation has been tried in these patients in order to avoid the complications related to endotracheal intubation, mainly ventilator-associated pneumonia. The potential usefulness of noninvasive ventilation in the ventilatory management of trauma patients, though reported in various studies, has not been sufficiently investigated on a large scale. According to the British Thoracic Society guidelines, the indications and efficacy of noninvasive ventilation treatment in respiratory distress induced by trauma have thus far been inconsistent and merely received a low grade recommendation. In this review paper, we analyse and compare the results of various studies in which noninvasive ventilation was applied and discuss the role and efficacy of this ventilator modality in trauma. PMID:25685722

  4. Mechanical ventilation in children.

    PubMed

    Kendirli, Tanil; Kavaz, Asli; Yalaki, Zahide; Oztürk Hişmi, Burcu; Derelli, Emel; Ince, Erdal

    2006-01-01

    Mechanical ventilation can be lifesaving, but > 50% of complications in conditions that require intensive care are related to ventilatory support, particularly if it is prolonged. We retrospectively evaluated the medical records of patients who had mechanical ventilation in the Pediatric Intensive Care Unit (PICU) during a follow-up period between January 2002-May 2005. Medical records of 407 patients were reviewed. Ninety-one patients (22.3%) were treated with mechanical ventilation. Ages of all patients were between 1-180 (median: 8) months. The mechanical ventilation time was 18.8 +/- 14.1 days. Indication of mechanical ventilation could be divided into four groups as respiratory failure (64.8%), cardiovascular failure (19.7%), central nervous system disease (9.8%) and safety airway (5.4%). Tracheostomy was performed in four patients. The complication ratio of mechanically ventilated children was 42.8%, and diversity of complications was as follows: 26.3% atelectasia, 17.5% ventilator-associated pneumonia, 13.1% pneumothorax, 5.4% bleeding, 4.3% tracheal edema, and 2.1% chronic lung disease. The mortality rate of mechanically ventilated patients was 58.3%, but the overall mortality rate in the PICU was 12.2%. In conclusion, there are few published epidemiological data on the follow-up results and mortality in infants and children who are mechanically ventilated. PMID:17290566

  5. Anaesthesia ventilators

    PubMed Central

    Jain, Rajnish K; Swaminathan, Srinivasan

    2013-01-01

    Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bellows ventilators, ascending bellows design is safer than descending bellows. Piston ventilators have the advantage of delivering accurate tidal volume. They work with electricity as their driving force and do not require a driving gas. To enable improved patient safety, several modifications were done in circle system with the different types of anaesthesia ventilators. Fresh gas decoupling is a modification done in piston ventilators and in descending bellows ventilator to reduce th incidence of ventilator induced volutrauma. In addition to the conventional volume control mode, modern anaesthesia ventilators also provide newer modes of ventilation such as synchronised intermittent mandatory ventilation, pressure-control ventilation and pressure-support ventilation (PSV). PSV mode is particularly useful for patients maintained on spontaneous respiration with laryngeal mask airway. Along with the innumerable benefits provided by these machines, there are various inherent hazards associated with the use of the ventilators in the operating room. To use these workstations safely, it is important for every Anaesthesiologist to have a basic understanding of the mechanics of these ventilators and breathing circuits. PMID:24249886

  6. Faster reduction in hyperinflation and improvement in lung ventilation inhomogeneity promoted by aclidinium compared to glycopyrronium in severe stable COPD patients. A randomized crossover study.

    PubMed

    Santus, Pierachille; Radovanovic, Dejan; Di Marco, Fabiano; Raccanelli, Rita; Valenti, Vincenzo; Centanni, Stefano

    2015-12-01

    Standard spyrometric assessment in chronic obstructive pulmonary disease (COPD) only evaluates bronchial obstruction. However, airflow limitation and hyperinflation are the main pathophysiological factors responsible for dyspnoea and reduced exercise tolerance in patients with COPD. This study evaluated the effects of aclidinium bromide 400 μg and glycopyrronium bromide 50 μg on these parameters. Patients with stable severe/very severe COPD were randomized in this double-blind, double-dummy, crossover, Phase IV study. Patients received single doses of each drug on separate days. Primary endpoints were changes in residual volume (RV) and intra-thoracic gas volume (ITGV), assessed by full-body plethysmography. Other endpoints included changes variations in lung ventilation inhomogeneity (Phase III slope of single-breath nitrogen washout test, SBN2), dyspnoea visual analogue scale, and pulmonary specific total airway resistances. Assessments were performed at baseline and 5, 15, 30, 60, and 180 min post-administration. Thirty-seven patients were randomized (31 male; mean age 71 years). Aclidinium and glycopyrronium significantly improved ITGV versus baseline at all-time points (p < 0.05). Significant improvements in RV were observed after 5 min with aclidinium and after 60 min with glycopyrronium. RV improvements were significantly greater with aclidinium than glycopyrronium from 5 to 60 min post-administration (p < 0.05). Both treatments improved dyspnoea versus baseline at all-time points (p < 0.05). Aclidinium significantly improved ventilation inhomogeneity versus baseline at all-time points; no significant changes were observed for glycopyrronium. For the first time two long-acting muscarinic antagonists have been compared in acute conditions with body plethysmography and SBN2 test. We demonstrated that both aclidinium and glycopyrronium significantly reduce hyperinflation and dyspnoea in severe and very severe COPD patients. Aclidinium however

  7. Effects of Blood Flow and/or Ventilation Restriction on Radiofrequency Coagulation Size in the Lung: An Experimental Study in Swine

    SciTech Connect

    Anai, Hiroshi; Uchida, Barry T.; Pavcnik, Dusan Seong, Chang Kyu; Baker, Phillip; Correa, Luiz Otavio; Corless, Christopher L.; Sakaguchi, Hiroshi; Kichikawa, Kimihiko; Keller, Frederick S.; Roesch, Josef

    2006-10-15

    The purpose of this study was to investigate how the restriction of blood flow and/or ventilation affects the radiofrequency (RF) ablation coagulation size in lung parenchyma. Thirty-one RF ablations were done in 16 normal lungs of 8 living swine with 2-cm LeVeen needles. Eight RF ablations were performed as a control (group G1), eight with balloon occlusion of the ipsilateral mainstem bronchus (G2), eight with occlusion of the ipsilateral pulmonary artery (G3), and seven with occlusion of both the ipsilateral bronchus and pulmonary artery (G4). Coagulation diameters and volumes of each ablation zone were compared on computed tomography (CT) and gross specimen examinations. Twenty-six coagulation zones were suitable for evaluation: eight in G1, five in G2, seven in G3, and six in G4 groups. In G1, the mean coagulation diameter was 21.5 {+-} 3.5 mm on CT and 19.5 {+-} 1.78 mm on gross specimen examination. In G2, the mean diameters were 26.5 {+-} 5.1 mm and 23.0 {+-} 2.7 mm on CT and gross specimen examination, respectively. In G3, the mean diameters were 29.4 {+-} 2.2 mm and 27.4 {+-} 2.9 mm on CT and gross specimen examination, respectively, and in G4, they were 32.6 {+-} 3.33 mm and 28.8 {+-} 2.6 mm, respectively. The mean coagulation volumes were 3.39 {+-} l.52 cm{sup 3} on CT and 3.01 {+-} 0.94 cm{sup 3} on gross examinations in G1, 6.56 {+-} 2.47 cm{sup 3} and 5.22 {+-} 0.85 cm{sup 3} in G2, 10.93 {+-} 2.17 cm{sup 3} and 9.97 {+-} 2.91 cm{sup 3} in G3, and 13.81 {+-} 3.03 cm{sup 3} and 11.06 {+-} 3.27 cm{sup 3} in G4, respectively. The mean coagulation diameters on gross examination and mean coagulation volumes on CT and gross examination with G3 and G4 were significantly larger than those in G1 (p < 0.0001, p < 0.0001, p < 0.0001, respectively) or in G2 (p < 0.05, p < 0.005, p < 0.005, respectively). Pulmonary collapse occurred in one lung in G2 and pulmonary artery thrombus in two lungs of G3 and two lungs of G4. The coagulation size of RF ablation of the

  8. Administration of hydrogen sulfide via extracorporeal membrane lung ventilation in sheep with partial cardiopulmonary bypass perfusion: a proof of concept study on metabolic and vasomotor effects

    PubMed Central

    2011-01-01

    Introduction Although inhalation of 80 parts per million (ppm) of hydrogen sulfide (H2S) reduces metabolism in mice, doses higher than 200 ppm of H2S were required to depress metabolism in rats. We therefore hypothesized that higher concentrations of H2S are required to reduce metabolism in larger mammals and humans. To avoid the potential pulmonary toxicity of H2S inhalation at high concentrations, we investigated whether administering H2S via ventilation of an extracorporeal membrane lung (ECML) would provide means to manipulate the metabolic rate in sheep. Methods A partial venoarterial cardiopulmonary bypass was established in anesthetized, ventilated (fraction of inspired oxygen = 0.5) sheep. The ECML was alternately ventilated with air or air containing 100, 200, or 300 ppm H2S for intervals of 1 hour. Metabolic rate was estimated on the basis of total CO2 production (V˙CO2) and O2 consumption (V˙O2). Continuous hemodynamic monitoring was performed via indwelling femoral and pulmonary artery catheters. Results V˙CO2, V˙O2, and cardiac output ranged within normal physiological limits when the ECML was ventilated with air and did not change after administration of up to 300 ppm H2S. Administration of 100, 200 and 300 ppm H2S increased pulmonary vascular resistance by 46, 52 and 141 dyn·s/cm5, respectively (all P ≤ 0.05 for air vs. 100, 200 and 300 ppm H2S, respectively), and mean pulmonary artery pressure by 4 mmHg (P ≤ 0.05), 3 mmHg (n.s.) and 11 mmHg (P ≤ 0.05), respectively, without changing pulmonary capillary wedge pressure or cardiac output. Exposure to 300 ppm H2S decreased systemic vascular resistance from 1,561 ± 553 to 870 ± 138 dyn·s/cm5 (P ≤ 0.05) and mean arterial pressure from 121 ± 15 mmHg to 66 ± 11 mmHg (P ≤ 0.05). In addition, exposure to 300 ppm H2S impaired arterial oxygenation (PaO2 114 ± 36 mmHg with air vs. 83 ± 23 mmHg with H2S; P ≤ 0.05). Conclusions Administration of up to 300 ppm H2S via ventilation of an

  9. Biomarkers for oxidative stress in acute lung injury induced in rabbits submitted to different strategies of mechanical ventilation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oxidative damage has been said to play an important role in pulmonary injury, which is associated with the development and progression of acute respiratory distress syndrome (ARDS). We aimed to identify biomarkers to determine the oxidative stress in an animal model of acute lung injury (ALI) using ...

  10. Mechanical ventilation in abdominal surgery.

    PubMed

    Futier, E; Godet, T; Millot, A; Constantin, J-M; Jaber, S

    2014-01-01

    One of the key challenges in perioperative care is to reduce postoperative morbidity and mortality. Patients who develop postoperative morbidity but survive to leave hospital have often reduced functional independence and long-term survival. Mechanical ventilation provides a specific example that may help us to shift thinking from treatment to prevention of postoperative complications. Mechanical ventilation in patients undergoing surgery has long been considered only as a modality to ensure gas exchange while allowing maintenance of anesthesia with delivery of inhaled anesthetics. Evidence is accumulating, however, suggesting an association between intraoperative mechanical ventilation strategy and postoperative pulmonary function and clinical outcome in patients undergoing abdominal surgery. Non-protective ventilator settings, especially high tidal volume (VT) (>10-12mL/kg) and the use of very low level of positive end-expiratory pressure (PEEP) (PEEP<5cmH2O) or no PEEP, may cause alveolar overdistension and repetitive tidal recruitment leading to ventilator-associated lung injury in patients with healthy lungs. Stimulated by previous findings in patients with acute respiratory distress syndrome, the use of lower tidal volume ventilation is becoming increasingly more common in the operating room. However, lowering tidal volume, though important, is only part of the overall multifaceted approach of lung protective mechanical ventilation. In this review, we aimed at providing the most recent and relevant clinical evidence regarding the use of mechanical ventilation in patients undergoing abdominal surgery.

  11. Inhalation therapy in mechanical ventilation

    PubMed Central

    Maccari, Juçara Gasparetto; Teixeira, Cassiano; Gazzana, Marcelo Basso; Savi, Augusto; Dexheimer-Neto, Felippe Leopoldo; Knorst, Marli Maria

    2015-01-01

    Patients with obstructive lung disease often require ventilatory support via invasive or noninvasive mechanical ventilation, depending on the severity of the exacerbation. The use of inhaled bronchodilators can significantly reduce airway resistance, contributing to the improvement of respiratory mechanics and patient-ventilator synchrony. Although various studies have been published on this topic, little is known about the effectiveness of the bronchodilators routinely prescribed for patients on mechanical ventilation or about the deposition of those drugs throughout the lungs. The inhaled bronchodilators most commonly used in ICUs are beta adrenergic agonists and anticholinergics. Various factors might influence the effect of bronchodilators, including ventilation mode, position of the spacer in the circuit, tube size, formulation, drug dose, severity of the disease, and patient-ventilator synchrony. Knowledge of the pharmacological properties of bronchodilators and the appropriate techniques for their administration is fundamental to optimizing the treatment of these patients. PMID:26578139

  12. Ventilation in chest trauma

    PubMed Central

    Richter, Torsten; Ragaller, Maximilian

    2011-01-01

    Chest trauma is one important factor for total morbidity and mortality in traumatized emergency patients. The complexity of injury in trauma patients makes it challenging to provide an optimal oxygenation while protecting the lung from further ventilator-induced injury to it. On the other hand, lung trauma needs to be treated on an individual basis, depending on the magnitude, location and type of lung or chest injury. Several aspects of ventilatory management in emergency patients are summarized herein and may give the clinician an overview of the treatment possibilities for chest trauma victims. PMID:21769213

  13. High-resolution computed tomography bronchial lumen to pulmonary artery diameter ratio in anesthetized ventilated cats with normal lungs.

    PubMed

    Reid, Lauren E; Dillon, A Ray; Hathcock, John T; Brown, Lawrence A; Tillson, Michael; Wooldridge, Anne A

    2012-01-01

    High-resolution computed tomography (CT) is the preferred noninvasive tool for diagnosing bronchiectasis in people. A criterion for evaluating dilation of the bronchus is the bronchial lumen to pulmonary artery diameter (bronchoarterial ratio [BA ratio]). A ratio of > 1.0 in humans or > 2.0 in dogs has been suggested as a threshold for identifying bronchiectasis. The purpose of this study was to establish the BA ratio in normal cats. Fourteen specific pathogen-free cats were selected for analysis of thoracic CT images. The BA ratios of the lobar bronchi of the left cranial (cranial and caudal parts), right cranial, right middle, left caudal, and right caudal lung lobes were measured. The mean of the mean BA ratio of all lung lobes was 0.71 +/- 0.05. Individual BA ratios ranged from 0.5 to 1.11. Comparing individual lobes for each cat, there was no significant difference (P = 0.145) in mean BA ratio between lung lobes. A mean BA ratio for these normal cats was 0.71 +/- 0.1, which suggests an upper cut-off normal value > 0.91 (mean +/- 2 standard deviations) between normal and abnormal cats.

  14. 4D-Imaging of the Lung: Reproducibility of Lesion Size and Displacement on Helical CT, MRI, and Cone Beam CT in a Ventilated Ex Vivo System

    SciTech Connect

    Biederer, Juergen Dinkel, Julien; Remmert, Gregor; Jetter, Siri; Nill, Simeon; Moser, Torsten; Bendl, Rolf; Thierfelder, Carsten; Fabel, Michael; Oelfke, Uwe; Bock, Michael; Plathow, Christian; Bolte, Hendrik; Welzel, Thomas; Hoffmann, Beata; Hartmann, Guenter; Schlegel, Wolfgang; Debus, Juergen; Heller, Martin

    2009-03-01

    Purpose: Four-dimensional (4D) imaging is a key to motion-adapted radiotherapy of lung tumors. We evaluated in a ventilated ex vivo system how size and displacement of artificial pulmonary nodules are reproduced with helical 4D-CT, 4D-MRI, and linac-integrated cone beam CT (CBCT). Methods and Materials: Four porcine lungs with 18 agarose nodules (mean diameters 1.3-1.9 cm), were ventilated inside a chest phantom at 8/min and subject to 4D-CT (collimation 24 x 1.2 mm, pitch 0.1, slice/increment 24x10{sup 2}/1.5/0.8 mm, pitch 0.1, temporal resolution 0.5 s), 4D-MRI (echo-shared dynamic three-dimensional-flash; repetition/echo time 2.13/0.72 ms, voxel size 2.7 x 2.7 x 4.0 mm, temporal resolution 1.4 s) and linac-integrated 4D-CBCT (720 projections, 3-min rotation, temporal resolution {approx}1 s). Static CT without respiration served as control. Three observers recorded lesion size (RECIST-diameters x/y/z) and axial displacement. Interobserver- and interphase-variation coefficients (IO/IP VC) of measurements indicated reproducibility. Results: Mean x/y/z lesion diameters in cm were equal on static and dynamic CT (1.88/1.87; 1.30/1.39; 1.71/1.73; p > 0.05), but appeared larger on MRI and CBCT (2.06/1.95 [p < 0.05 vs. CT]; 1.47/1.28 [MRI vs. CT/CBCT p < 0.05]; 1.86/1.83 [CT vs. CBCT p < 0.05]). Interobserver-VC for lesion sizes were 2.54-4.47% (CT), 2.29-4.48% (4D-CT); 5.44-6.22% (MRI) and 4.86-6.97% (CBCT). Interphase-VC for lesion sizes ranged from 2.28% (4D-CT) to 10.0% (CBCT). Mean displacement in cm decreased from static CT (1.65) to 4D-CT (1.40), CBCT (1.23) and MRI (1.16). Conclusions: Lesion sizes are exactly reproduced with 4D-CT but overestimated on 4D-MRI and CBCT with a larger variability due to limited temporal and spatial resolution. All 4D-modalities underestimate lesion displacement.

  15. Home Mechanical Ventilation in Children.

    PubMed

    Preutthipan, Aroonwan

    2015-09-01

    The number of children dependent on home mechanical ventilation has been reported to be increasing in many countries around the world. Home mechanical ventilation has been well accepted as a standard treatment of children with chronic respiratory failure. Some children may need mechanical ventilation as a lifelong therapy. To send mechanically ventilated children back home may be more difficult than adults. However, relatively better outcomes have been demonstrated in children. Children could be safely ventilated at home if they are selected and managed properly. Conditions requiring home ventilation include increased respiratory load from airway or lung pathologies, ventilatory muscle weakness and failure of neurologic control of ventilation. Home mechanical ventilation should be considered when the patient develops progressive respiratory failure or intractable failure to wean mechanical ventilation. Polysomnography or overnight pulse oximetry plus capnometry are used to detect nocturnal hypoventilation in early stage of respiratory failure. Ventilator strategy including non-invasive and invasive approach should be individualized for each patient. The author strongly believes that parents and family members are able to take care of their child at home if they are trained and educated effectively. A good team work with dedicated members is the key factor of success. PMID:26223874

  16. [The effect of extrapleural thoracoplasty on the mechanical properties of lungs and ventilation indices in advanced fibrous-cavernous tuberculosis].

    PubMed

    Strelis, A K; Lenskaia, L G

    1994-01-01

    Basing on clinical data obtained on 42 patients, the authors prove the existence of changes in all the respiratory biomechanical parameters, primarily viscosity, in response to development of advanced fibrous-cavernous tuberculosis in the lungs. Disorders in the bronchopulmonary mechanics depend on the terms of collapsosurgical intervention and its efficacy. The viscosity-induced resistance to respiration results basically from inflammation of the tracheobronchial tree and bronchospasm. An increase in the bronchial resistance in the early postoperative period occurs both in effective and uneffective extrapleural thoracoplasty, while later on it is observed only after uneffective and corrective collapsosurgical interventions. Basic biomechanical parameters of respiration (total performance, extensibility, bronchial resistance) together with spirographic and clinicoroentgenological evidence can be of help in predicting the effect of the surgery itself. A positive response of collapsosurgical interventions on respiratory biomechanics can be judged from a persistent fall in total respiratory performance irrespective of surgical effectivity.

  17. Hypertrophic osteoarthropathy manifested with isolated calcaneal periostitis in bone scintigraphy.

    PubMed

    Moralidis, Efstratios; Gerasimou, Georgios; Theodoridou, Athina; Hilidis, Ilias; Mylonaki, Efrosyni; Gotzamani-Psarrakou, Anna

    2010-05-01

    Hypertrophic osteoarthropathy (HOA) is an incompletely understood syndrome characterized by digital clubbing and periosteal proliferation of long bones and it is commonly associated with primary lung tumors. Bone scintigraphy is a sensitive method in detecting HOA and characteristic findings have been reported. We present the case of a man with newly diagnosed non-small cell lung cancer, unremarkable clinical examination and blood tests and no digital clubbing. During disease staging, however, bone scintigraphy showed intense calcaneal cortical proliferation bilaterally without involvement of other parts of the skeleton. Cortical reaction of both calcanei resolved significantly after chemotherapy. This case indicates that HOA may manifest with isolated calcaneal periostitis bilaterally, which is a new addition to the literature.

  18. 99mTc-MIBI Lung Scintigraphy in the Assessment of Pulmonary Involvement in Interstitial Lung Disease and Its Comparison With Pulmonary Function Tests and High-Resolution Computed Tomography: A Preliminary Study.

    PubMed

    Bahtouee, Mehrzad; Saberifard, Jamshid; Javadi, Hamid; Nabipour, Iraj; Raeisi, Alireza; Assadi, Majid; Eftekhari, Mohammad

    2015-11-01

    The differentiation of active inflammatory processes from an inactive form of the disease is of great value in the management of interstitial lung disease (ILD). The aim of this investigation was to assess the efficacy of 99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI) scans in distinguishing the severity of the disease compared to radiological and clinical parameters.In total, 19 known cases of ILD were included in this study and were followed up for 1 year. Five patients without lung disease were considered as the control group. The patients underwent pulmonary function tests (PFTs) and high-resolution computed tomography scans, followed by 99mTc-MIBI scanning. The 99mTc-MIBI scans were analyzed either qualitatively (subjectively) or semiquantitatively.All 19 ILD patients demonstrated a strong increase in 99mTc-MIBI uptake in the lungs compared to the control group. The 99mTc-MIBI scan scores were higher in the patient group in both the early phase (0.24[0.19-0.31] vs 0.11[0.10-0.15], P < 0.05) and the delayed phase (0.15[0.09-0.27] vs 0.04[0.01-0.09], P < 0.05) compared with the control group. A positive correlation was detected between the 99mTc-MIBI scan and the high-resolution computed tomography (HRCT) scores (Spearman's correlation coefficient = 0.65, P < 0.02) in the early phase but not in the delayed phase in patients (P > 0.14). The 99mTc-MIBI scan scores were not significantly correlated with the PFT findings (P > 0.05). In total, 5 patients died and 14 patients were still alive over the 1-year follow-up period. There was also a significant difference between the uptake intensity of 99mTc-MIBI and the outcome in the early phase (dead: 0.32[0.29-0.43] vs alive: 0.21[0.18-0.24], P < 0.05) and delayed phase (dead: 0.27[0.22-0.28] vs alive: 0.10[0.07-0.19], P < 0.05).The washout rate was ~40 min starting from 20 min up to 60 min and this rate was significantly different in our 2 study groups (ILD: 46.61[15.61-50.39] vs NL: 70.91[27.09-116.36], P = 0.04).The

  19. 99mTc-MIBI Lung Scintigraphy in the Assessment of Pulmonary Involvement in Interstitial Lung Disease and Its Comparison With Pulmonary Function Tests and High-Resolution Computed Tomography

    PubMed Central

    Bahtouee, Mehrzad; Saberifard, Jamshid; Javadi, Hamid; Nabipour, Iraj; Raeisi, Alireza; Assadi, Majid; Eftekhari, Mohammad

    2015-01-01

    Abstract The differentiation of active inflammatory processes from an inactive form of the disease is of great value in the management of interstitial lung disease (ILD). The aim of this investigation was to assess the efficacy of 99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI) scans in distinguishing the severity of the disease compared to radiological and clinical parameters. In total, 19 known cases of ILD were included in this study and were followed up for 1 year. Five patients without lung disease were considered as the control group. The patients underwent pulmonary function tests (PFTs) and high-resolution computed tomography scans, followed by 99mTc-MIBI scanning. The 99mTc-MIBI scans were analyzed either qualitatively (subjectively) or semiquantitatively. All 19 ILD patients demonstrated a strong increase in 99mTc-MIBI uptake in the lungs compared to the control group. The 99mTc-MIBI scan scores were higher in the patient group in both the early phase (0.24[0.19–0.31] vs 0.11[0.10–0.15], P < 0.05) and the delayed phase (0.15[0.09–0.27] vs 0.04[0.01–0.09], P < 0.05) compared with the control group. A positive correlation was detected between the 99mTc-MIBI scan and the high-resolution computed tomography (HRCT) scores (Spearman's correlation coefficient = 0.65, P < 0.02) in the early phase but not in the delayed phase in patients (P > 0.14). The 99mTc-MIBI scan scores were not significantly correlated with the PFT findings (P > 0.05). In total, 5 patients died and 14 patients were still alive over the 1-year follow-up period. There was also a significant difference between the uptake intensity of 99mTc-MIBI and the outcome in the early phase (dead: 0.32[0.29–0.43] vs alive: 0.21[0.18–0.24], P < 0.05) and delayed phase (dead: 0.27[0.22–0.28] vs alive: 0.10[0.07–0.19], P < 0.05). The washout rate was ∼40 min starting from 20 min up to 60 min and this rate was significantly different in our 2 study groups (ILD: 46

  20. 99mTc-IgG-Lung Scintigraphy in the Assessment of Pulmonary Involvement in Interstitial Lung Disease and Its Comparison With Pulmonary Function Tests and High-Resolution Computed Tomography: A Preliminary Study

    PubMed Central

    Bahtouee, Mehrzad; Saberifard, Jamshid; Javadi, Hamid; Nabipour, Iraj; Malakizadeh, Hasan; Monavvarsadegh, Gholamhossein; Ilkhani Pak, Hoda; Sadeghi, Azadeh; Assadi, Majid

    2015-01-01

    Background: The discrimination of inactive inflammatory processes from the active form of the disease is of great importance in the management of interstitial lung disease (ILD). Objectives: The aim of this study was to determine the efficacy of 99mTc-IgG scan for the detection of severity of disease compared to high-resolution computed tomography (HRCT) and pulmonary function test (PFT). Patients and Methods: Eight known cases of ILD including four cases of Mustard gas (MG) intoxication and four patients with ILD of unknown cause were included in this study. A population of six patients without lung disease was considered as the control group. The patients underwent PFT and high-resolution computed tomography, followed by 99mTc-IgG scan. They were followed up for one year. 99mTc-IgG scan assessment of IgG uptake was accomplished both qualitatively (subjectively) and semiquantitatively. Results: All eight ILD patients demonstrated a strong increase in 99mTc-IgG uptake in the lungs, compared to the control patients. The 99mTc-IgG scan scores were higher in the patient group (0.64[95% confidence interval(CI)=0.61-0.69])) than the control group (0.35 (0.35[95% CI=0.28-0.40]), (P<0.05)). In patients, a statistically significant positive correlation was detected between 99mTc-IgG scan and HRCT scores (Spearman’s correlation coefficient = 0.92, P < 0.008). The 99mTc-Human Immunoglobulin (HIG) scores were not significantly correlated with PFT findings (including FVC, FEV1, FEV1/FVC), O2 saturation and age ( P values > 0.05). There were no significant correlations between 99mTc-IgG score and HRCT patterns including ground glass opacity, reticular fibrosis and honeycombing (P value > 0.05). Conclusion: The present results confirmed that 99mTc-IgG scan could be applied to detect the severity of pulmonary involvement, which was well correlated with HRCT findings. This data also showed that the 99mTc-IgG scan might be used as a complement to HRCT in the functional evaluation

  1. Transpleural Ventilation via Spiracles in Severe Emphysema Increases Alveolar Ventilation.

    PubMed

    Chahla, Mayy; Larson, Christopher D; Parekh, Kalpaj R; Reed, Robert M; Terry, Peter; Schmidt, Gregory A; Eberlein, Michael

    2016-06-01

    In emphysema airway resistance can exceed collateral airflow resistance, causing air to flow preferentially through collateral pathways. In severe emphysema ventilation through openings directly through the chest wall into the parenchyma (spiracles) could bypass airway obstruction and increase alveolar ventilation via transpleural expiration. During lung transplant operations, spiracles occasionally can occur inadvertently. We observed transpleural expiration via spiracles in three subjects undergoing lung transplant for emphysema. During transpleural spiracle ventilation, inspiratory tidal volumes (TV) were unchanged; however, expiration was entirely transpleural in two patients whereas the expired TV to the ventilator circuit was reduced to 25% of the inspired TV in one. At baseline, mean PCO2 was 61 ± 5 mm Hg, which decreased to a mean PCO2 of 49 ± 5 mm Hg (P = .05) within minutes after transpleural spiracle ventilation and further decreased at 1 to 2 h (36 ± 4 mm Hg; P = .002 compared with baseline) on unchanged ventilator settings. This observation of increased alveolar ventilation supports further studies of spiracles as a possible therapy for advanced emphysema. PMID:27287591

  2. Scotland's first iron lung.

    PubMed

    Porter, I A; Williams, M J

    1997-08-01

    The history of artificial ventilation and the development of the iron lung in the USA by Drinker and his colleagues is discussed. The building and use of an iron lung by Dr R G Henderson in Aberdeen in 1933 is described. The development of other types of ventilator in the UK is recorded and the circumstances whereby positive pressure ventilation was introduced in Denmark in 1952 is outlined. PMID:9507591

  3. Ventilation Model

    SciTech Connect

    H. Yang

    1999-11-04

    The purpose of this analysis and model report (AMR) for the Ventilation Model is to analyze the effects of pre-closure continuous ventilation in the Engineered Barrier System (EBS) emplacement drifts and provide heat removal data to support EBS design. It will also provide input data (initial conditions, and time varying boundary conditions) for the EBS post-closure performance assessment and the EBS Water Distribution and Removal Process Model. The objective of the analysis is to develop, describe, and apply calculation methods and models that can be used to predict thermal conditions within emplacement drifts under forced ventilation during the pre-closure period. The scope of this analysis includes: (1) Provide a general description of effects and heat transfer process of emplacement drift ventilation. (2) Develop a modeling approach to simulate the impacts of pre-closure ventilation on the thermal conditions in emplacement drifts. (3) Identify and document inputs to be used for modeling emplacement ventilation. (4) Perform calculations of temperatures and heat removal in the emplacement drift. (5) Address general considerations of the effect of water/moisture removal by ventilation on the repository thermal conditions. The numerical modeling in this document will be limited to heat-only modeling and calculations. Only a preliminary assessment of the heat/moisture ventilation effects and modeling method will be performed in this revision. Modeling of moisture effects on heat removal and emplacement drift temperature may be performed in the future.

  4. Liver scintigraphy in veterinary medicine.

    PubMed

    Morandi, Federica

    2014-01-01

    The most common veterinary application of liver scintigraphy is for the diagnosis of portosystemic shunts (PSSs). There has been a continual evolution of nuclear medicine techniques for diagnosis of PSS, starting in the early 1980s. Currently, transplenic portal scintigraphy using pertechnetate or (99m)Tc-mebrofenin is the technique of choice. This technique provides both anatomical and functional information about the nature of the PSS, with high sensitivity and specificity. Hepatobiliary scintigraphy has also been used in veterinary medicine for the evaluation of liver function and biliary patency. Hepatobiliary scintigraphy provides information about biliary patency that complements finding in ultrasound, which may not be able to differentiate between biliary ductal dilation from previous obstruction vs current obstruction. Hepatocellular function can also be determined by deconvolutional analysis of hepatic uptake or by measuring the clearance of the radiopharmaceutical from the plasma. Plasma clearance of the radiopharmaceutical can be directly measured from serial plasma samples, as in the horse, or by measuring changes in cardiac blood pool activity by region of interest analysis of images. The objective of this paper is to present a summary of the reported applications of hepatobiliary scintigraphy in veterinary medicine.

  5. High-Frequency Jet Ventilation for Complete Target Immobilization and Reduction of Planning Target Volume in Stereotactic High Single-Dose Irradiation of Stage I Non-Small Cell Lung Cancer and Lung Metastases

    SciTech Connect

    Fritz, Peter; Kraus, Hans-Joerg; Muehlnickel, Werner; Sassmann, Volker; Hering, Werner; Strauch, Konstantin

    2010-09-01

    Purpose: To demonstrate the feasibility of complete target immobilization by means of high-frequency jet ventilation (HFJV); and to show that the saving of planning target volume (PTV) on the stereotactic body radiation therapy (SBRT) under HFJV, compared with SBRT with respiratory motion, can be predicted with reliable accuracy by computed tomography (CT) scans at peak inspiration phase. Methods and Materials: A comparison regarding different methods for defining the PTV was carried out in 22 patients with tumors that clearly moved with respiration. A movement span of the gross tumor volume (GTV) was defined by fusing respiration-correlated CT scans. The PTV enclosed the GTV positions with a safety margin throughout the breathing cycle. To create a PTV from CT scans acquired under HFJV, the same margins were drawn around the immobilized target. In addition, peak inspiration phase CT images (PIP-CTs) were used to approximate a target immobilized by HFJV. Results: The resulting HFJV-PTVs were between 11.6% and 45.4% smaller than the baseline values calculated as respiration-correlated CT-PTVs (median volume reduction, 25.4%). Tentative planning by means of PIP-CT PTVs predicted that in 19 of 22 patients, use of HFJV would lead to a reduction in volume of {>=}20%. Using this threshold yielded a positive predictive value of 0.89, as well as a sensitivity of 0.94 and a specificity of 0.5. Conclusions: In all patients, SBRT under HFJV provided a reliable immobilization of the GTVs and achieved a reduction in PTVs, regardless of patient compliance. Tentative planning facilitated the selection of patients who could better undergo radiation in respiratory standstill, both with greater accuracy and lung protection.

  6. Patient-ventilator interaction during acute lung injury, and the role of spontaneous breathing: part 1: respiratory muscle function during critical illness.

    PubMed

    Kallet, Richard H

    2011-02-01

    Since the early 1970s there has been an ongoing debate regarding the wisdom of promoting unassisted spontaneous breathing throughout the course of critical illness in patients with severe respiratory failure. The basis of this debate has focused on the clinical relevance of opposite problems. Historically, the term "disuse atrophy" has described a situation wherein sustained inactivity of the respiratory muscles (ie, passive ventilation) results in deconditioning and weakness. More recently it has been referred to as "ventilator-induced diaphragmatic dysfunction." In contrast, "use atrophy" describes a situation where chronic high-tension inspiratory work causes structural damage to the diaphragm and weakness. Both laboratory and clinical studies demonstrated that relatively brief periods of complete respiratory muscle inactivity, as well as intense muscle loading, result in acute inflammation, loss of muscle mass, and weakness. Yet in critical illness other factors also affect respiratory muscle function, including prolonged use of neuromuscular blocking agents, administration of corticosteroids, and sepsis. This makes the attribution of acquired respiratory muscle weakness and ventilator-dependence to either ventilator-induced diaphragmatic dysfunction or loaded breathing extremely difficult. Regardless, the clinical implications of this research strongly suggest that passive mechanical ventilation should be avoided whenever possible. However, promotion of unassisted spontaneous breathing in the acute phase of critical illness also may carry a substantial risk of respiratory muscle injury and weakness. Use of mechanical ventilation modes in a manner that induces spontaneous breathing effort, while simultaneously reducing the work load on the respiratory muscles, is probably sufficient to minimize both problems.

  7. Ventilation Model

    SciTech Connect

    V. Chipman

    2002-10-05

    The purpose of the Ventilation Model is to simulate the heat transfer processes in and around waste emplacement drifts during periods of forced ventilation. The model evaluates the effects of emplacement drift ventilation on the thermal conditions in the emplacement drifts and surrounding rock mass, and calculates the heat removal by ventilation as a measure of the viability of ventilation to delay the onset of peak repository temperature and reduce its magnitude. The heat removal by ventilation is temporally and spatially dependent, and is expressed as the fraction of heat carried away by the ventilation air compared to the fraction of heat produced by radionuclide decay. One minus the heat removal is called the wall heat fraction, or the remaining amount of heat that is transferred via conduction to the surrounding rock mass. Downstream models, such as the ''Multiscale Thermohydrologic Model'' (BSC 2001), use the wall heat fractions as outputted from the Ventilation Model to initialize their post-closure analyses. The Ventilation Model report was initially developed to analyze the effects of preclosure continuous ventilation in the Engineered Barrier System (EBS) emplacement drifts, and to provide heat removal data to support EBS design. Revision 00 of the Ventilation Model included documentation of the modeling results from the ANSYS-based heat transfer model. The purposes of Revision 01 of the Ventilation Model are: (1) To validate the conceptual model for preclosure ventilation of emplacement drifts and verify its numerical application in accordance with new procedural requirements as outlined in AP-SIII-10Q, Models (Section 7.0). (2) To satisfy technical issues posed in KTI agreement RDTME 3.14 (Reamer and Williams 2001a). Specifically to demonstrate, with respect to the ANSYS ventilation model, the adequacy of the discretization (Section 6.2.3.1), and the downstream applicability of the model results (i.e. wall heat fractions) to initialize post

  8. 21 CFR 868.5935 - External negative pressure ventilator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false External negative pressure ventilator. 868.5935... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung, cuirass) is...

  9. 21 CFR 868.5935 - External negative pressure ventilator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External negative pressure ventilator. 868.5935... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung, cuirass) is...

  10. 21 CFR 868.5935 - External negative pressure ventilator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false External negative pressure ventilator. 868.5935... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung, cuirass) is...

  11. 21 CFR 868.5935 - External negative pressure ventilator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false External negative pressure ventilator. 868.5935... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung, cuirass) is...

  12. 21 CFR 868.5935 - External negative pressure ventilator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false External negative pressure ventilator. 868.5935... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung, cuirass) is...

  13. Thyroid scintigraphy in veterinary medicine.

    PubMed

    Daniel, Gregory B; Neelis, Dana A

    2014-01-01

    Thyroid scintigraphy is performed in cats and dogs and has been used to a limited degree in other species such as the horse. Thyroid scintigraphy is most commonly used to aid in the diagnosis and treatment management of feline hyperthyroidism but is also used in the evaluation of canine hypothyroidism and canine thyroid carcinoma. This article reviews the normal scintigraphic appearance of the thyroid in the cat, the dog, and the horse and the principles of interpretation of abnormal scan results in the cat and the dog. Radioiodine is the treatment of choice for feline hyperthyroidism, and the principles of its use in the cat are reviewed.

  14. Lung models: strengths and limitations.

    PubMed

    Martonen, T B; Musante, C J; Segal, R A; Schroeter, J D; Hwang, D; Dolovich, M A; Burton, R; Spencer, R M; Fleming, J S

    2000-06-01

    The most widely used particle dosimetry models are those proposed by the National Council on Radiation Protection, International Commission for Radiological Protection, and the Netherlands National Institute of Public Health and the Environment (the RIVM model). Those models have inherent problems that may be regarded as serious drawbacks: for example, they are not physiologically realistic. They ignore the presence and commensurate effects of naturally occurring structural elements of lungs (eg, cartilaginous rings, carinal ridges), which have been demonstrated to affect the motion of inhaled air. Most importantly, the surface structures have been shown to influence the trajectories of inhaled particles transported by air streams. Thus, the model presented herein by Martonen et al may be perhaps the most appropriate for human lung dosimetry. In its present form, the model's major "strengths" are that it could be used for diverse purposes in medical research and practice, including: to target the delivery of drugs for diseases of the respiratory tract (eg, cystic fibrosis, asthma, bronchogenic carcinoma); to selectively deposit drugs for systemic distribution (eg, insulin); to design clinical studies; to interpret scintigraphy data from human subject exposures; to determine laboratory conditions for animal testing (ie, extrapolation modeling); and to aid in aerosolized drug delivery to children (pediatric medicine). Based on our research, we have found very good agreement between the predictions of our model and the experimental data of Heyder et al, and therefore advocate its use in the clinical arena. In closing, we would note that for the simulations reported herein the data entered into our computer program were the actual conditions of the Heyder et al experiments. However, the deposition model is more versatile and can simulate many aerosol therapy scenarios. For example, the core model has many computer subroutines that can be enlisted to simulate the

  15. AIRWAY IDENTIFICATION WITHIN PLANAR GAMMA CAMERA IMAGES USING COMPUTER MODELS OF LUNG MORPHOLOGY

    EPA Science Inventory

    The quantification of inhaled aerosols could be improved if a more comprehensive assessment of their spatial distribution patterns among lung airways were obtained. A common technique for quantifying particle deposition in human lungs is with planar gamma scintigraphy. However, t...

  16. The lung in space

    NASA Technical Reports Server (NTRS)

    Prisk, G. Kim

    2005-01-01

    The lung is exquisitely sensitive to gravity, which induces gradients in ventilation, blood flow, and gas exchange. Studies of lungs in microgravity provide a means of elucidating the effects of gravity. They suggest a mechanism by which gravity serves to match ventilation to perfusion, making for a more efficient lung than anticipated. Despite predictions, lungs do not become edematous, and there is no disruption to, gas exchange in microgravity. Sleep disturbances in microgravity are not a result of respiratory-related events; obstructive sleep apnea is caused principally by the gravitational effects on the upper airways. In microgravity, lungs may be at greater risk to the effects of inhaled aerosols.

  17. Gallium scintigraphy in acute panniculitis

    SciTech Connect

    Choy, D.; Murray, I.P.C.; Ford, J.C.

    1981-11-01

    Gallium scintigraphy was performed in a 27-yr-old female in search of a possible occult focus of infection; it showed an unusual diffuse superficial accumulation in the thighs and buttocks. Biopsy of an area of abnormal uptake showed lobular panniculitis which, in the clinical context, led to the diagnosis of Weber-Christian syndrome.

  18. Thallium 201 Scintigraphy

    PubMed Central

    McKillop, James H.

    1980-01-01

    The radioactive isotope thallium 201 behaves physiologically as a potassium analog, and when injected intravenously accumulates rapidly within the cells of many organs. Uptake of the isotope reflects both regional perfusion and sodium-potassium pump activity. The radionuclide emits 80 keV x-rays which are suitable for scintillation camera imaging. The main clinical application of 201TI scintigraphy has been in myocardial imaging. Abnormal uptake of the isotope results in a cold spot on the myocardial image. In patients with coronary artery disease, the differentiation of ischemic and infarcted myocardium is made by comparing images obtained after injecting the radionuclide at the peak of a maximal exercise test with those obtained after injection at rest. Abnormalities due to ischemia usually are seen only on the stress image whereas fixed defects in both rest and stress studies usually indicate areas of infarction or scarring. Some investigators believe that redistribution images obtained four to six hours after stress injection (without administering further 201TI) give the same information as a separate rest study. The sensitivity of stress imaging for detecting significant coronary disease is of the order of 80 percent to 95 percent, though computer processing of the images may be necessary to achieve the higher figure. The prediction of the extent of coronary disease from 201TI images is less reliable. An abnormal 201TI image is not entirely specific for coronary artery disease and the likelihood of an abnormal image being due to this diagnosis varies according to the clinical circumstances. The main clinical value of 201TI myocardial imaging is likely to be in the noninvasive screening of patients with atypical chest pain or with ambiguous findings on stress electrocardiographic tests. It has also proved useful in studying patients with variant angina or following a coronary bypass operation. It is doubtful whether the technique is clinically helpful in most

  19. Comparison of 4-Dimensional Computed Tomography Ventilation With Nuclear Medicine Ventilation-Perfusion Imaging: A Clinical Validation Study

    SciTech Connect

    Vinogradskiy, Yevgeniy; Koo, Phillip J.; Castillo, Richard; Castillo, Edward; Guerrero, Thomas; Gaspar, Laurie E.; Miften, Moyed; Kavanagh, Brian D.

    2014-05-01

    Purpose: Four-dimensional computed tomography (4DCT) ventilation imaging provides lung function information for lung cancer patients undergoing radiation therapy. Before 4DCT-ventilation can be implemented clinically it needs to be validated against an established imaging modality. The purpose of this work was to compare 4DCT-ventilation to nuclear medicine ventilation, using clinically relevant global metrics and radiologist observations. Methods and Materials: Fifteen lung cancer patients with 16 sets of 4DCT and nuclear medicine ventilation-perfusion (VQ) images were used for the study. The VQ-ventilation images were acquired in planar mode using Tc-99m-labeled diethylenetriamine-pentaacetic acid aerosol inhalation. 4DCT data, spatial registration, and a density-change-based model were used to compute a 4DCT-based ventilation map for each patient. The percent ventilation was calculated in each lung and each lung third for both the 4DCT and VQ-ventilation scans. A nuclear medicine radiologist assessed the VQ and 4DCT scans for the presence of ventilation defects. The VQ and 4DCT-based images were compared using regional percent ventilation and radiologist clinical observations. Results: Individual patient examples demonstrate good qualitative agreement between the 4DCT and VQ-ventilation scans. The correlation coefficients were 0.68 and 0.45, using the percent ventilation in each individual lung and lung third, respectively. Using radiologist-noted presence of ventilation defects and receiver operating characteristic analysis, the sensitivity, specificity, and accuracy of the 4DCT-ventilation were 90%, 64%, and 81%, respectively. Conclusions: The current work compared 4DCT with VQ-based ventilation using clinically relevant global metrics and radiologist observations. We found good agreement between the radiologist's assessment of the 4DCT and VQ-ventilation images as well as the percent ventilation in each lung. The agreement lessened when the data were analyzed

  20. Tc-99m macro aggregated albumin scintigraphy – indications other than pulmonary embolism: A pictorial essay

    PubMed Central

    Gandhi, Sunny J; Babu, Sanjay; Subramanyam, Padma; Shanmuga Sundaram, Palaniswamy

    2013-01-01

    Introduction: Tc-99m macro aggregated albumin (MAA) is synonymous for lung perfusion scintigraphy and is part of the study in the evaluation of pulmonary thromboembolism. We wanted to highlight the utilities of Tc-99m MAA other than pulmonary embolism as a pictorial assay. Materials and Methods: Patients referred for Tc-99m MAA scintigraphy under various indications were included in this pictorial essay. Commercially available TechneScan LyoMAA cold kit from Mallinckrodt Medical B.V., Holland was used. Acquisition protocols for different indications are described in this article. Different clinical indications (e.g., pulmonary artery stenosis, hepatopulmonary syndrome, FEV1 calculation in lung surgery planning, selective internal radiation therapy planning, venography for deep venous thrombosis, left to right cardiac shunts, etc.) where Tc-99m MAA scintigraphy was asked for; how it helped in different clinical scenarios and how it can be used clinically is explained with unique and interesting case examples and images. We also reviewed the literature to look for certain remote indications of MAA imaging for the sake of completion like – (shunt scintigraphy, peritoneopleural communication, etc.) Conclusion: Tc-99m MAA is a very useful radiopharmaceutical, which can be used for many other indications apart from the commonly used indication of lung perfusion scan in pulmonary embolism. It can provide useful clinical information in other indications, which we try to highlight in this article. PMID:24250023

  1. [Home mechanical ventilation-tracheostomy ventilation, for the long-term and variation].

    PubMed

    Yamamoto, Makoto

    2006-12-01

    We experienced long-term ventilation for 30 patients mostly with amyotrophic lateral sclerosis (ALS). For long-term ventilation by tracheostomy positive pressure ventilation (TPPV), we must set tidal volume (TV) over 600 ml, because setting 400 ml as TV usually applied in Japan, often develops atelectasis which causes frequent or serious pneumonia. To avoid both the elevation of airway pressure and hyper ventilation, the following intervals are needed: 10 times/min for breathing frequency and 2 seconds for exhaling time. In the cases with ventilator induced lung injury (VILI), it is necessary to lower the TV and to treat with steroid pulse therapy. In the transitional stage from non-invasive positive pressure ventilation (NPPV) to TPPV, we conduct tracheostomy for suction of the sputum. In that stage, by using a cuffless tracheal canule, we can continue NPPV. As another method in that stage, we recommend biphasic management by NPPV at daytime and TPPV at nighttime with a bi-level ventilator. This method can provide certain ventilation also during sleep. When the respiratory failure proceeds further, we manage the ventilation with a bi-level ventilator on TPPV, because a bi-level ventilator is also good adapting to assist spontaneous breathing in that stage. And if the patient does not have bulbar paralysis, the patient can utter by air leakage with using bi-level ventilator and flattening the cuff of the tracheal canule. PMID:17469348

  2. One-lung anesthesia update.

    PubMed

    Mirzabeigi, Edwin; Johnson, Calvin; Ternian, Alen

    2005-09-01

    One-lung ventilation is used during a variety of cardiac, thoracic, and major vascular procedures. Endobronchial tubes, bronchial blockers, and occasionally, single-lumen tubes are used to isolate the lungs. Patients with difficult airways and pediatric patients provide special challenges for lung isolation. Finally, intraoperative hypoxia and hypercarbia in patients with intrinsic lung disease frequently complicate one-lung anesthesia. The concepts and controversies in lung isolation techniques are discussed.

  3. Mechanical Ventilation

    MedlinePlus

    ... or husband or next of kin). It is important that you talk with your family members and your doctors about using a ventilator and what you would like to happen in different situations. The more clearly you explain your values and choices to friends, loved ones and doctors, ...

  4. Airway Injury from Initiating Ventilation in Preterm Sheep

    PubMed Central

    Hillman, Noah H.; Kallapur, Suhas G.; Pillow, J. Jane; Moss, Timothy J. M.; Polglase, Graeme R.; Nitsos, Ilias; Jobe, Alan H.

    2009-01-01

    Premature infants exposed to ventilation are at risk of developing bronchopulmonary dysplasia (BPD) and persistent lung disease in childhood. We report where injury occurred within the lung following brief ventilation at birth. Preterm sheep (129d gestation) were ventilated with an escalating VT to 15mL/kg by 15 min to injure the lungs, with the placental circulation intact (Fetal) or after delivery (Newborn). Fetal lambs were returned to the uterus for 2h 45min, while Newborn lambs were maintained with gentle ventilatory support for the same period. The control group was not ventilated. Bronchoalveolar lavage fluid (BALF) and lung tissue were analysed. In both Fetal and Newborn lambs, ventilation caused bronchial epithelial disruption in medium-sized airways. Egr-1, MCP-1, IL-6, and IL-1β mRNA increased in lung tissue from Fetal and Newborn lambs. Egr-1, MCP-1 and IL-6 mRNA were induced in mesenchymal cells surrounding small airways, whereas IL-1β mRNA localized to the epithelium of medium/small airways. Ventilation caused loss of HSP70 mRNA from the bronchial epithelium, but induced mRNA in smooth muscle surrounding large airways. HSP70 protein decreased in lung tissue and increased in BALF with ventilation. Initiation of ventilation induced a stress response and inflammatory cytokines in small and medium-sized airways. PMID:19816239

  5. Time and volume dependence of dead space in healthy and surfactant-depleted rat lungs during spontaneous breathing and mechanical ventilation.

    PubMed

    Dassow, Constanze; Schwenninger, David; Runck, Hanna; Guttmann, Josef

    2013-11-01

    Volumetric capnography is a standard method to determine pulmonary dead space. Hereby, measured carbon dioxide (CO2) in exhaled gas volume is analyzed using the single-breath diagram for CO2. Unfortunately, most existing CO2 sensors do not work with the low tidal volumes found in small animals. Therefore, in this study, we developed a new mainstream capnograph designed for the utilization in small animals like rats. The sensor was used for determination of dead space volume in healthy and surfactant-depleted rats (n = 62) during spontaneous breathing (SB) and mechanical ventilation (MV) at three different tidal volumes: 5, 8, and 11 ml/kg. Absolute dead space and wasted ventilation (dead space volume in relation to tidal volume) were determined over a period of 1 h. Dead space increase and reversibility of the increase was investigated during MV with different tidal volumes and during SB. During SB, the dead space volume was 0.21 ± 0.14 ml and increased significantly at MV to 0.39 ± 0.03 ml at a tidal volume of 5 ml/kg and to 0.6 ± 0.08 ml at a tidal volume of 8 and 11 ml/kg. Dead space and wasted ventilation during MV increased with tidal volume. This increase was mostly reversible by switching back to SB. Surfactant depletion had no further influence on the dead space increase during MV, but impaired the reversibility of the dead space increase.

  6. Time and volume dependence of dead space in healthy and surfactant-depleted rat lungs during spontaneous breathing and mechanical ventilation.

    PubMed

    Dassow, Constanze; Schwenninger, David; Runck, Hanna; Guttmann, Josef

    2013-11-01

    Volumetric capnography is a standard method to determine pulmonary dead space. Hereby, measured carbon dioxide (CO2) in exhaled gas volume is analyzed using the single-breath diagram for CO2. Unfortunately, most existing CO2 sensors do not work with the low tidal volumes found in small animals. Therefore, in this study, we developed a new mainstream capnograph designed for the utilization in small animals like rats. The sensor was used for determination of dead space volume in healthy and surfactant-depleted rats (n = 62) during spontaneous breathing (SB) and mechanical ventilation (MV) at three different tidal volumes: 5, 8, and 11 ml/kg. Absolute dead space and wasted ventilation (dead space volume in relation to tidal volume) were determined over a period of 1 h. Dead space increase and reversibility of the increase was investigated during MV with different tidal volumes and during SB. During SB, the dead space volume was 0.21 ± 0.14 ml and increased significantly at MV to 0.39 ± 0.03 ml at a tidal volume of 5 ml/kg and to 0.6 ± 0.08 ml at a tidal volume of 8 and 11 ml/kg. Dead space and wasted ventilation during MV increased with tidal volume. This increase was mostly reversible by switching back to SB. Surfactant depletion had no further influence on the dead space increase during MV, but impaired the reversibility of the dead space increase. PMID:23950167

  7. Positional effects on distribution of ventilation in chronic obstructive pulmonary disease

    SciTech Connect

    Shim, C.; Chun, K.J.; Williams, M.H. Jr.; Blaufox, M.D.

    1986-09-01

    Ventilation is distributed predominantly to the dependent lung in normal persons in the decubitus position. We evaluated the distribution of ventilation in four patients with mild-to-moderate chronic obstructive pulmonary disease using 81mKr gas. Patients were tested in the sitting and right and left decubitus positions with and without the application of positive end expiratory pressure (PEEP). In contrast to findings in controls, ventilation was predominantly distributed to the nondependent lung in patients in the decubitus position. Mean ventilation in the right lung decreased from 51% of the total in the sitting position to 31% in the right decubitus position; it increased with the application of 10 cm PEEP. Reduced ventilation in the dependent lung most likely is caused by closure of the airways after a decrease in volume. Application of PEEP resulted in increased lung volume and preferential distribution of ventilation to the dependent lung.

  8. Radionuclides in detecting active granuloma formation. Gallium-67 scintigraphy and histopathology with autoradiographic findings

    SciTech Connect

    van Maarsseveen, A.; Alberts, C.; van der Schoot, J.; van Royen, E.; Hens, C.; Mullink, H.; de Groot, J.

    1986-01-01

    Granuloma formation studies were performed on lungs of guinea pigs sensitized with FCA over 2 to 17 months. Prolonged time of sensitization revealed more granulomatous pulmonary tissue. An intravenous booster of FCA in the animals that had been sensitized for 3 months yielded enhanced granuloma formation within 5 days. The histopathology of these lungs was comparable with that seen in lungs of animals after 17 months of sensitization without booster. Enhanced local proliferation of macrophages, measured by (/sup 3/H)thymidine incorporation and autoradiography, was seen in the lungs of the animals that had received boosters. Moreover, /sup 67/Ga scintigraphy was strongly positive in these animals. Scintigraphy of cell suspensions of pulmonary tissue from these animals showed that /sup 67/Ga was predominantly taken up (quantitatively as well as qualitatively) by the alveolar macrophages. Cell suspensions of sarcoidosis patients, prepared in the same way, showed only a low level of /sup 67/Ga uptake, one comparable to that of the pulmonary cell suspensions of the sensitized animals that had not received boosters. It is suggested that a negative scintigraphy in patients with chronic pulmonary granulomatous disorders could be (partly) explained by the absence of activated macrophages.

  9. Prediction of cardiac events after uncomplicated myocardial infarction: a prospective study comparing predischarge exercise thallium-201 scintigraphy and coronary angiography

    SciTech Connect

    Gibson, R.S.; Watson, D.D.; Craddock, G.B.; Crampton, R.S.; Kaiser, D.L.; Denny, M.J.; Beller, G.A.

    1983-08-01

    The ability of predischarge quantitative exercise thallium-201 (/sup 201/T1) scintigraphy to predict future cardiac events was evaluated prospectively in 140 consecutive patients with uncomplicated acute myocardial infarction; the results were compared with those of submaximal exercise treadmill testing and coronary angiography. High risk was assigned if scintigraphy detected /sup 201/T1 defects in more than one discrete vascular region, redistribution, or increased lung uptake, if exercise testing caused ST segment depression greater than or equal to 1 mm or angina or if angiography revealed multivessel disease. Low risk was designated if scintigraphy detected a single-region defect, no redistribution, or no increase in lung uptake, if exercise testing caused no ST segment depression or angina, or if angiography revealed single-vessel disease or no disease. By 15 +/- 12 months, 50 patients had experienced a cardiac event; seven died (five suddenly), nine suffered recurrent myocardial infarction, and 34 developed severe class III or IV angina pectoris. Compared with that of patients at low risk, the cumulative probability of a cardiac event was greater in high-risk patients identified by scintigraphy, exercise testing, or angiography. Scintigraphy predicted low-risk status better than exercise testing or angiography. Each predicted mortality with equal accuracy. These results indicate that (1) submaximal exercise /sup 201/T1 scintigraphy can distinguish high- and low-risk groups after uncomplicated acute myocardial infarction before hospital discharge; (2) /sup 201/T1 defects in more than one discrete vascular region, presence of delayed redistribution, or increased lung thallium uptake are more sensitive predictors of subsequent cardiac events than ST segment depression, angina, or extent of angiographic disease; and (3) low-risk patients are best identified by a single-region /sup 201/T1 defect without redistribution and no increased lung uptake.

  10. Lung Function and Organ Dysfunctions in 178 Patients Requiring Mechanical Ventilation During The 2009 Influenza A (H1N1) Pandemic

    PubMed Central

    2011-01-01

    Introduction Most cases of the 2009 influenza A (H1N1) infection are self-limited, but occasionally the disease evolves to a severe condition needing hospitalization. Here we describe the evolution of the respiratory compromise, ventilatory management and laboratory variables of patients with diffuse viral pneumonitis caused by pandemic 2009 influenza A (H1N1) admitted to the ICU. Method This was a multicenter, prospective inception cohort study including adult patients with acute respiratory failure requiring mechanical ventilation (MV) admitted to 20 ICUs in Argentina between June and September of 2009 during the influenza A (H1N1) pandemic. In a standard case-report form, we collected epidemiological characteristics, results of real-time reverse-transcriptase--polymerase-chain-reaction viral diagnostic tests, oxygenation variables, acid-base status, respiratory mechanics, ventilation management and laboratory tests. Variables were recorded on ICU admission and at days 3, 7 and 10. Results During the study period 178 patients with diffuse viral pneumonitis requiring MV were admitted. They were 44 ± 15 years of age, with Acute Physiology And Chronic Health Evaluation II (APACHE II) scores of 18 ± 7, and most frequent comorbidities were obesity (26%), previous respiratory disease (24%) and immunosuppression (16%). Non-invasive ventilation (NIV) was applied in 49 (28%) patients on admission, but 94% were later intubated. Acute respiratory distress syndrome (ARDS) was present throughout the entire ICU stay in the whole group (mean PaO2/FIO2 170 ± 25). Tidal-volumes used were 7.8 to 8.1 ml/kg (ideal body weight), plateau pressures always remained < 30 cmH2O, without differences between survivors and non-survivors; and mean positive end-expiratory pressure (PEEP) levels used were between 8 to 12 cm H2O. Rescue therapies, like recruitment maneuvers (8 to 35%), prone positioning (12 to 24%) and tracheal gas insufflation (3%) were frequently applied. At all time points

  11. [Respiratory and extracorporeal lung support].

    PubMed

    Lotz, Christopher; Roewer, Norbert; Muellenbach, Ralf M

    2016-09-01

    Mechanical ventilation is the most commonly used form of respiratory support to restore or maintain adequate gas exchange. However, mechanical ventilation does not provide a physiological form of breathing. Neither does it provide an optimal ventilation / perfusion ratio due to passive movement of the diagphragm favoring the non-dependent parts of the lung. Furthermore, patients are in danger of ventilator-associated/induced lung injury (VALI/VILI). Hence, lung protective ventilation is mandatory in patients with an acute respiratory distress syndrome (ARDS) and should likewise be used in the operating room. Extracorporeal pulmonary support is required in case mechanical ventilation is unable to secure sufficient gas exchange or VILI is imminent. Venovenous extracorporeal membrane oxygenation (vvECMO) acts as lung replacement therapy and may improve survival along with treatment in an ARDS-center. PMID:27631452

  12. REDUCTION IN INSPIRATORY FLOW ATTENUATES IL-8 RELEASE AND MAPK ACTIVATION OF LUNG OVERSTRETCH

    EPA Science Inventory

    Lung overstretch involves mechanical factors, including large tidal volumes (VT), which induce inflammatory responses. The current authors hypothesised that inspiratory flow contributes to ventilator-induced inflammation. Buffer-perfused rabbit lungs were ventilated for 2 h with ...

  13. Electrical Impedance Tomography During Mechanical Ventilation.

    PubMed

    Walsh, Brian K; Smallwood, Craig D

    2016-10-01

    Electrical impedance tomography (EIT) is a noninvasive, non-radiologic imaging modality that may be useful for the quantification of lung disorders and titration of mechanical ventilation. The principle of operation is based on changes in electrical conductivity that occur as a function of changes in lung volume during ventilation. EIT offers potentially important benefits over standard imaging modalities because the system is portable and non-radiologic and can be applied to patients for long periods of time. Rather than providing a technical dissection of the methods utilized to gather, compile, reconstruct, and display EIT images, the present article seeks to provide an overview of the clinical application of this technology as it relates to monitoring mechanical ventilation and providing decision support at the bedside. EIT has been shown to be useful in the detection of pneumothoraces, quantification of pulmonary edema and comparison of distribution of ventilation between different modes of ventilation and may offer superior individual titration of PEEP and other ventilator parameters compared with existing approaches. Although application of EIT is still primarily done within a research context, it may prove to be a useful bedside tool in the future. However, head-to-head comparisons with existing methods of mechanical ventilation titration in humans need to be conducted before its application in general ICUs can be recommended. PMID:27682815

  14. Sensitivity of scintigraphy for detection of pulmonary capillary albumin leak in canine oleic acid ARDS

    SciTech Connect

    Sugerman, H.J.; Strash, A.M.; Hirsch, J.I.; Glauser, F.L.; Shirazi, K.K.; Sharp, D.E.; Greenfield, L.J.

    1981-07-01

    Computerized gamma scintigraphy was shown in this study to be a sensitive technique for the detection and kinetic analysis of a pulmonary capillary protein leak. A rising lung:heart radioactivity of slope of injury was found at each dose of intravenous oleic acid in dogs from 0.01 to 0.20 ml/kg (p less than 0.01). This slope of injury was proportional to the dose of oleic acid (r . +0.97; p less than 0.004) and was more sensitive than changes in arterial oxygen tension, standard chest radiography, bloodless wet:dry lung weight, or alveolar epithelial membrane permeability. Only standard light microscopy and right lymphatic duct flow were able to document the leakage of protein detected by gamma scintigraphy at 0.01 ml/kg oleic acid.

  15. Experimental studies on artificial ventilation using a tidal volume ventilator. Mechanics and dynamics of ventilation.

    PubMed

    Lindahl, S; Okmian, L

    1979-08-01

    In 24 piglets (2.7-24.5 kg b.w.), the mechanics of ventilation, the accuracy of dosage of respiratory volumes, and the influence of the ventilator's volume/pressure characteristics (Cvent, "internal compliance") on the dynamic course of insufflation were studied. A linear relationship was shown to exist between tidal volume and end-inspiratory tracheal pressure and between tidal volume and insufflation time. The insufflation time was reduced to about 50% of previously registered values. The error between set and registered tidal volume was found to be 6.0 +/- 2.7%. During the insufflation a linear relationship was found between the instant amount of delivered breathing gas and the corresponding endotracheal pressure change. The ventilator's Cvent did (and body size, total compliance and tidal volume did not) significantly influence the size of the direction coefficient for the linear instantaneous volume/pressure relationship, the magnitude of tracheal peak pressure and a short insufflation time, and vice versa. The use of greater power from the ventilator resulted in a significant shortening of the duration of insufflation and vice versa. The duration of insufflation is the parameter of choice in evaluating the efficiency of the ventilatory equipment. When the ventilator's performance is defined, measurements of the duration of insufflation may enable evaluation of conditions within the lungs.

  16. Radionuclide scintigraphy of bacterial nephritis

    SciTech Connect

    Conway, J.J.; Weiss, S.C.; Shkolnik, A.; Yogev, R.; Firlit, C.; Traisman, E.S.

    1984-01-01

    Pyelonephritis is a leading cause of renal failure and is expected to cost as much as three billion dollars in 1984. The diagnosis of urinary tract infection is usually not difficult. However, localization of the infection within the renal parenchyma as opposed to the collecting system is much more difficult. Flank pain, fever, bacteiuria and evidence of parenchymal involvement by intravenous urography may be absent or unrecognized particularly in the infant. Ultrasound and Nuclear Medicine are advocated as better methods to define parenchymal involvement. Such definition is important in the consideration of treatment since parenchymal involvement of the kidney carries a much more ominous potential outcome than infection restricted to within the collecting system. 38 children with a clinical diagnosis of urinary tract infection were studied. 26 of the patients demonstrated abnormal renal parenchymal findings with Gallium-67 Citrate or Tc-99m Glucoheptonate scintigraphy. Intravenous urography was notably ineffective with only 5 of the 20 interpreted as abnormal due to parenchymal disease or decreased function. 11 were entirely normal while only 5 demonstrated scars or hydronephrosis. Only 10 of 17 patients demonstrated intranvesicoureteral reflux on x-ray or nuclear cystography. Ultrasound depicted 6 of 20 patients as having parenchymal abnormalities. Seven were normal. Nonspecific findings such as dilitation of the renal pelvis or renal enlargement was noted in 11 of the 20 patients. Radionuclide Scintigraphy is the most efficacious modality to detect since acute bacterial nephritis.

  17. A randomized trial to assess the utility of preintubation adult fiberoptic bronchoscope assessment in patients for thoracic surgery requiring one-lung ventilation

    PubMed Central

    Amin, Nayana; Tarwade, Pritee; Shetmahajan, Madhavi; Pramesh, C. S.; Jiwnani, Sabita; Mahajan, Abhishek; Purandare, Nilendu

    2016-01-01

    Background: Confirmation of placement of Double lumen endobronchial tubes (DLETT) and bronchial blockers (BBs) with the pediatric fiberoptic bronchoscope (FOB) is the most preferred practice worldwide. Most centers possess standard adult FOBs, some, particularly in developing countries might not have access to the pediatric-sized devices. We have evaluated the role of preintubation airway assessment using the former, measuring the distance from the incisors to the carina and from carina to the left and right upper lobe bronchus in deciding the depth of insertion of the lung isolation device. Methods: The study was a randomized, controlled, double-blind trial consisting of 84 patients (all >18 years) undergoing thoracic surgery over a 12-month period. In the study group (n = 38), measurements obtained during FOB with the adult bronchoscope decided the depth of insertion of the lung isolation device. In the control group (n = 46), DLETTs and BBs were placed blindly followed by clinical confirmation by auscultation. Selection of the type and size of the lung isolation device was at the discretion of the anesthesiologist conducting the case. In all cases, pediatric FOB was used to confirm accurate placement of devices. Results: Of 84 patients (DLETT used in 76 patients; BB used in 8 patients), preintubation airway measurements significantly improved the success rate of optimal placement of lung isolation device from 25% (11/44) to 50% (18/36) (P = 0.04). Our incidence of failed device placement at initial insertion was 4.7% (4/84). Incidence of malposition was 10% (8/80) with 4 cases in each group. The incidence of suboptimal placement was lower in the study group at 38.9% (14/36) versus 65.9% (29/44). Conclusions: Preintubation airway measurements with the adult FOB reduces airway manipulations and improves the success rate of optimal placement of DLETT and BB. PMID:27052065

  18. New modes of assisted mechanical ventilation.

    PubMed

    Suarez-Sipmann, F

    2014-05-01

    Recent major advances in mechanical ventilation have resulted in new exciting modes of assisted ventilation. Compared to traditional ventilation modes such as assisted-controlled ventilation or pressure support ventilation, these new modes offer a number of physiological advantages derived from the improved patient control over the ventilator. By implementing advanced closed-loop control systems and using information on lung mechanics, respiratory muscle function and respiratory drive, these modes are specifically designed to improve patient-ventilator synchrony and reduce the work of breathing. Depending on their specific operational characteristics, these modes can assist spontaneous breathing efforts synchronically in time and magnitude, adapt to changing patient demands, implement automated weaning protocols, and introduce a more physiological variability in the breathing pattern. Clinicians have now the possibility to individualize and optimize ventilatory assistance during the complex transition from fully controlled to spontaneous assisted ventilation. The growing evidence of the physiological and clinical benefits of these new modes is favoring their progressive introduction into clinical practice. Future clinical trials should improve our understanding of these modes and help determine whether the claimed benefits result in better outcomes.

  19. New modes of assisted mechanical ventilation.

    PubMed

    Suarez-Sipmann, F

    2014-05-01

    Recent major advances in mechanical ventilation have resulted in new exciting modes of assisted ventilation. Compared to traditional ventilation modes such as assisted-controlled ventilation or pressure support ventilation, these new modes offer a number of physiological advantages derived from the improved patient control over the ventilator. By implementing advanced closed-loop control systems and using information on lung mechanics, respiratory muscle function and respiratory drive, these modes are specifically designed to improve patient-ventilator synchrony and reduce the work of breathing. Depending on their specific operational characteristics, these modes can assist spontaneous breathing efforts synchronically in time and magnitude, adapt to changing patient demands, implement automated weaning protocols, and introduce a more physiological variability in the breathing pattern. Clinicians have now the possibility to individualize and optimize ventilatory assistance during the complex transition from fully controlled to spontaneous assisted ventilation. The growing evidence of the physiological and clinical benefits of these new modes is favoring their progressive introduction into clinical practice. Future clinical trials should improve our understanding of these modes and help determine whether the claimed benefits result in better outcomes. PMID:24507472

  20. Laxative Related Primary Hyperphosphatemic Tumoral Calcinosis Identified by Bone Scintigraphy.

    PubMed

    Asokendaran, Marcus; Lenzo, Nat Patrick

    2016-09-01

    We describe a case of a 40-year-old female patient presenting with tumor calcinosis where hypertrophic pulmonary osteoarthropathy (HPOA) was suspected given her extensive history of malignancy. Plain X-rays did not show reveal the typical periarticular calcification but did show appearances consistent with HPOA. Bone scintigraphy with (99m)Tc-methylene diphosphonate (MDP) is a sensitive investigation in the detection of hypertrophic osteoarthopathy but did not show findings characteristics of HPOA like bilateral symmetrical increased uptake of the radiopharmaceutical along the cortical margins of the long bones. The final diagnosis of tumor calcinosis was only made after low dose computerized tomography chest showed a moderated sized amorphous calcified cluster in the apical segment of the right upper lobe consistent. In conclusion, bone scintigraphy continues to be a useful investigation for both common and rare conditions like tumor calcinosis. The unusual three phase bone scan finding of diffuse activity throughout both lung fields, which turned to out to be tumoral calcinosis is highlighted in this case. PMID:27651742

  1. Laxative Related Primary Hyperphosphatemic Tumoral Calcinosis Identified by Bone Scintigraphy

    PubMed Central

    Asokendaran, Marcus; Lenzo, Nat Patrick

    2016-01-01

    We describe a case of a 40-year-old female patient presenting with tumor calcinosis where hypertrophic pulmonary osteoarthropathy (HPOA) was suspected given her extensive history of malignancy. Plain X-rays did not show reveal the typical periarticular calcification but did show appearances consistent with HPOA. Bone scintigraphy with 99mTc-methylene diphosphonate (MDP) is a sensitive investigation in the detection of hypertrophic osteoarthopathy but did not show findings characteristics of HPOA like bilateral symmetrical increased uptake of the radiopharmaceutical along the cortical margins of the long bones. The final diagnosis of tumor calcinosis was only made after low dose computerized tomography chest showed a moderated sized amorphous calcified cluster in the apical segment of the right upper lobe consistent. In conclusion, bone scintigraphy continues to be a useful investigation for both common and rare conditions like tumor calcinosis. The unusual three phase bone scan finding of diffuse activity throughout both lung fields, which turned to out to be tumoral calcinosis is highlighted in this case. PMID:27651742

  2. Laxative Related Primary Hyperphosphatemic Tumoral Calcinosis Identified by Bone Scintigraphy

    PubMed Central

    Asokendaran, Marcus; Lenzo, Nat Patrick

    2016-01-01

    We describe a case of a 40-year-old female patient presenting with tumor calcinosis where hypertrophic pulmonary osteoarthropathy (HPOA) was suspected given her extensive history of malignancy. Plain X-rays did not show reveal the typical periarticular calcification but did show appearances consistent with HPOA. Bone scintigraphy with 99mTc-methylene diphosphonate (MDP) is a sensitive investigation in the detection of hypertrophic osteoarthopathy but did not show findings characteristics of HPOA like bilateral symmetrical increased uptake of the radiopharmaceutical along the cortical margins of the long bones. The final diagnosis of tumor calcinosis was only made after low dose computerized tomography chest showed a moderated sized amorphous calcified cluster in the apical segment of the right upper lobe consistent. In conclusion, bone scintigraphy continues to be a useful investigation for both common and rare conditions like tumor calcinosis. The unusual three phase bone scan finding of diffuse activity throughout both lung fields, which turned to out to be tumoral calcinosis is highlighted in this case.

  3. Continuous distributions of specific ventilation recovered from inert gas washout

    NASA Technical Reports Server (NTRS)

    Lewis, S. M.; Evans, J. W.; Jalowayski, A. A.

    1978-01-01

    A new technique is described for recovering continuous distributions of ventilation as a function of tidal ventilation/volume ratio from the nitrogen washout. The analysis yields a continuous distribution of ventilation as a function of tidal ventilation/volume ratio represented as fractional ventilations of 50 compartments plus dead space. The procedure was verified by recovering known distributions from data to which noise had been added. Using an apparatus to control the subject's tidal volume and FRC, mixed expired N2 data gave the following results: (a) the distributions of young, normal subjects were narrow and unimodal; (b) those of subjects over age 40 were broader with more poorly ventilated units; (c) patients with pulmonary disease of all descriptions showed enlarged dead space; (d) patients with cystic fibrosis showed multimodal distributions with the bulk of the ventilation going to overventilated units; and (e) patients with obstructive lung disease fell into several classes, three of which are illustrated.

  4. Radionuclide bone scintigraphy in pediatric orthopedics

    SciTech Connect

    Conway, J.J.

    1986-12-01

    Radionuclide bone scintigraphy is highly sensitive and specific for diagnosing the musculoskeletal disorders of childhood. Conditions such as neonatal osteomyelitis, septic arthritis, diskitis of childhood, Legg-Calve-Perthes disease, the osteochondroses, the toddler's fracture, sports injuries, spondylolysis, myositis ossificians, and reflex sympathetic dystrophy are readily defined. High-quality state-of-the-art scintigraphy is essential in infants and young children. 64 references.

  5. Normal gallbladder scintigraphy in acute cholecystitis

    SciTech Connect

    Ohrt, H.J.; Posalaky, I.P.; Shafer, R.B.

    1983-03-01

    Normal gallbladder scintigraphy occurs in 2 to 5% of reported patients with acute cholecystitis. Gallbladder visualization is found in patients with acalculous cholecystitis and in those with recent relief of cystic duct obstruction but persistence of inflammation. A patient is reported who had clinical and pathologic findings of acute cholecystitis but normal gallbladder visualization. This reemphasizes that the diagnosis of acute cholecystitis cannot be excluded by normal gallbladder scintigraphy.

  6. Biliary scintigraphy in acute pancreatitis

    SciTech Connect

    Serafini, A.N.; Al-Sheikh, W.; Barkin, J.S.; Hourani, M.; Sfakiankis, G.; Clarke, L.P.; Ashkar, F.S.

    1982-08-01

    A prospective study was carried out in 60 patients to determine the efficacy of /sup 99m/Tc-PIPIDA scintigraphy in differentiating biliary pancreatitis from nonbiliary pancreatitis. Forty patients were classified as having biliary pancreatitis and 20 patients as having the nonbiliary type. Scintigraphic scans were divided into five main types according to the time to visualization of the gallbladder and the time to excretion of /sup 99m/Tc-PIPIDA into the intestinal tract. Normal scans were obtained on 95% of patients (19/20) with nonbiliary pancreatitis; 22.5% of patients (9/40) with biliary pancreatitis had normal scans. It is concluded that elevated amylase levels together with an abnormal biliary scan, as defined by the criteria presented here, indicate biliary pancreatitis, while a normal scan largely excludes such diagnosis.

  7. Biliary scintigraphy in acute pancreatitis

    SciTech Connect

    Serafini, A.N.; Al-Sheikh, W.; Barkin, J.S.; Hourani, M.; Sfakiankis, G.; Clarke, L.P.; Ashkar, F.S.

    1982-08-01

    A prospective study was carried out in 60 patients to determine the efficacy of /sup 99//sup m/Tc-PIPIDA scintigraphy in differentiating biliary pancreatitis from nonbiliary pancreatitis. Forty patients were classified as having biliary pancreatitis and 20 patients as having the nonbiliary type. Scintigraphic scans were divided into five main types according to the time to visualization of the gallbladder and the time to excretion of /sup 99//sup m/Tc-PIPIDA into the intestinal tract. Normal scans were obtained in 95% of patients (19/20) with nonbiliary pancreatitis; 22.5% of patients (9/40) with biliary pancreatitis had normal scans. It is concluded that elevated amylase levels together with an abnormal biliary scan, as defined by the criteria presented here, indicate biliary pancreatitis, while a normal scan largely excludes such diagnosis.

  8. [Lung hyperinflation after single lung transplantation to treat emphysema].

    PubMed

    Samano, Marcos Naoyuki; Junqueira, Jader Joel Machado; Teixeira, Ricardo Henrique de Oliveira Braga; Caramori, Marlova Luzzi; Pêgo-Fernandes, Paulo Manuel; Jatene, Fabio Biscegli

    2010-01-01

    Despite preventive measures, lung hyperinflation is a relatively common complication following single lung transplantation to treat pulmonary emphysema. The progressive compression of the graft can cause mediastinal shift and respiratory failure. In addition to therapeutic strategies such as independent ventilation, the treatment consists of the reduction of native lung volume by means of lobectomy or lung volume reduction surgery. We report two cases of native lung hyperinflation after single lung transplantation. Both cases were treated by means of lobectomy or lung volume reduction surgery.

  9. 21 CFR 868.5740 - Tracheal/bronchial differential ventilation tube.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tracheal/bronchial differential ventilation tube.../bronchial differential ventilation tube. (a) Identification. A tracheal/bronchial differential ventilation tube is a device used to isolate the left or the right lung of a patient for anesthesia or...

  10. 21 CFR 868.5740 - Tracheal/bronchial differential ventilation tube.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Tracheal/bronchial differential ventilation tube.../bronchial differential ventilation tube. (a) Identification. A tracheal/bronchial differential ventilation tube is a device used to isolate the left or the right lung of a patient for anesthesia or...

  11. 21 CFR 868.5740 - Tracheal/bronchial differential ventilation tube.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Tracheal/bronchial differential ventilation tube.../bronchial differential ventilation tube. (a) Identification. A tracheal/bronchial differential ventilation tube is a device used to isolate the left or the right lung of a patient for anesthesia or...

  12. 21 CFR 868.5740 - Tracheal/bronchial differential ventilation tube.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Tracheal/bronchial differential ventilation tube.../bronchial differential ventilation tube. (a) Identification. A tracheal/bronchial differential ventilation tube is a device used to isolate the left or the right lung of a patient for anesthesia or...

  13. 21 CFR 868.5740 - Tracheal/bronchial differential ventilation tube.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Tracheal/bronchial differential ventilation tube.../bronchial differential ventilation tube. (a) Identification. A tracheal/bronchial differential ventilation tube is a device used to isolate the left or the right lung of a patient for anesthesia or...

  14. VENTILATION NEEDS DURING CONSTRUCTION

    SciTech Connect

    C.R. Gorrell

    1998-07-23

    The purpose of this analysis is to determine ventilation needs during construction and development of the subsurface repository and develop systems to satisfy those needs. For this analysis, construction is defined as pre-emplacement excavation and development is excavation that takes place simultaneously with emplacement. The three options presented in the ''Overall Development and Emplacement Ventilation Systems'' analysis (Reference 5.5) for development ventilation will be applied to construction ventilation in this analysis as well as adding new and updated ventilation factors to each option for both construction and development. The objective of this analysis is to develop a preferred ventilation system to support License Application Design. The scope of this analysis includes: (1) Description of ventilation conditions; (2) Ventilation factors (fire hazards, dust control, construction logistics, and monitoring and control systems); (3) Local ventilation alternatives; (4) Global ventilation options; and (5) Evaluation of options.

  15. The added value of hybrid ventilation/perfusion SPECT/CT in patients with stable COPD or apparently healthy smokers. Cancer-suspected CT findings in the lungs are common when hybrid imaging is used.

    PubMed

    Jögi, Jonas; Markstad, Hanna; Tufvesson, Ellen; Bjermer, Leif; Bajc, Marika

    2015-01-01

    Ventilation/perfusion (V/P) single-photon emission computed tomography (SPECT) is recognized as a diagnostic method with potential beyond the diagnosis of pulmonary embolism. V/P SPECT identifies functional impairment in diseases such as heart failure (HF), pneumonia, and chronic obstructive pulmonary disease (COPD). The development of hybrid SPECT/computed tomography (CT) systems, combining functional with morphological imaging through the addition of low-dose CT (LDCT), may be useful in COPD, as these patients are prone to lung cancer and other comorbidities. The aim of this study was to investigate the added value of LDCT among healthy smokers and patients with stable COPD, when examined with V/P SPECT/CT hybrid imaging. Sixty-nine subjects, 55 with COPD (GOLD I-IV) and 14 apparently healthy smokers, were examined with V/P SPECT and LDCT hybrid imaging. Spirometry was used to verify COPD grade. Only one apparently healthy smoker and three COPD patients had a normal or nearly normal V/P SPECT. All other patients showed various degrees of airway obstruction, even when spirometry was normal. The same interpretation was reached on both modalities in 39% of the patients. LDCT made V/P SPECT interpretation more certain in 9% of the patients and, in 52%, LDCT provided additional diagnoses. LDCT better characterized the type of emphysema in 12 patients. In 19 cases, tumor-suspected changes were reported. Three of these 19 patients (ie, 4.3% of all subjects) were in the end confirmed to have lung cancer. The majority of LDCT findings were not regarded as clinically significant. V/P SPECT identified perfusion patterns consistent with decompensated left ventricular HF in 14 COPD patients. In 16 patients (23%), perfusion defects were observed. HF and perfusion defects were not recognized with LDCT. In COPD patients and long-time smokers, hybrid imaging had added value compared to V/P SPECT alone, by identifying patients with lung malignancy and more clearly identifying

  16. The added value of hybrid ventilation/perfusion SPECT/CT in patients with stable COPD or apparently healthy smokers. Cancer-suspected CT findings in the lungs are common when hybrid imaging is used.

    PubMed

    Jögi, Jonas; Markstad, Hanna; Tufvesson, Ellen; Bjermer, Leif; Bajc, Marika

    2015-01-01

    Ventilation/perfusion (V/P) single-photon emission computed tomography (SPECT) is recognized as a diagnostic method with potential beyond the diagnosis of pulmonary embolism. V/P SPECT identifies functional impairment in diseases such as heart failure (HF), pneumonia, and chronic obstructive pulmonary disease (COPD). The development of hybrid SPECT/computed tomography (CT) systems, combining functional with morphological imaging through the addition of low-dose CT (LDCT), may be useful in COPD, as these patients are prone to lung cancer and other comorbidities. The aim of this study was to investigate the added value of LDCT among healthy smokers and patients with stable COPD, when examined with V/P SPECT/CT hybrid imaging. Sixty-nine subjects, 55 with COPD (GOLD I-IV) and 14 apparently healthy smokers, were examined with V/P SPECT and LDCT hybrid imaging. Spirometry was used to verify COPD grade. Only one apparently healthy smoker and three COPD patients had a normal or nearly normal V/P SPECT. All other patients showed various degrees of airway obstruction, even when spirometry was normal. The same interpretation was reached on both modalities in 39% of the patients. LDCT made V/P SPECT interpretation more certain in 9% of the patients and, in 52%, LDCT provided additional diagnoses. LDCT better characterized the type of emphysema in 12 patients. In 19 cases, tumor-suspected changes were reported. Three of these 19 patients (ie, 4.3% of all subjects) were in the end confirmed to have lung cancer. The majority of LDCT findings were not regarded as clinically significant. V/P SPECT identified perfusion patterns consistent with decompensated left ventricular HF in 14 COPD patients. In 16 patients (23%), perfusion defects were observed. HF and perfusion defects were not recognized with LDCT. In COPD patients and long-time smokers, hybrid imaging had added value compared to V/P SPECT alone, by identifying patients with lung malignancy and more clearly identifying

  17. Tsunami lung.

    PubMed

    Inoue, Yoshihiro; Fujino, Yasuhisa; Onodera, Makoto; Kikuchi, Satoshi; Shozushima, Tatsuyori; Ogino, Nobuyoshi; Mori, Kiyoshi; Oikawa, Hirotaka; Koeda, Yorihiko; Ueda, Hironobu; Takahashi, Tomohiro; Terui, Katsutoshi; Nakadate, Toshihide; Aoki, Hidehiko; Endo, Shigeatsu

    2012-04-01

    We encountered three cases of lung disorders caused by drowning in the recent large tsunami that struck following the Great East Japan Earthquake. All three were females, and two of them were old elderly. All segments of both lungs were involved in all the three patients, necessitating ICU admission and endotracheal intubation and mechanical ventilation. All three died within 3 weeks. In at least two cases, misswallowing of oil was suspected from the features noted at the time of the detection. Sputum culture for bacteria yielded isolation of Stenotrophomonas maltophilia, Legionella pneumophila, Burkholderia cepacia, and Pseudomonas aeruginosa. The cause of tsunami lung may be a combination of chemical induced pneumonia and bacterial pneumonia.

  18. Hepatic anomalous lobulation demonstrated by liver and hepatobiliary scintigraphy

    SciTech Connect

    Arakawa, K.; Hoshi, H.; Jinnouchi, S.; Ono, S.; Kihara, Y.; Takeuchi, M.; Wakuta, Y.; Kakitsubata, Y.; Watanabe, K.

    1984-10-01

    The use of liver and hepatobiliary scintigraphy for evaluation of the hepatobiliary system in patients with hepatic disease is now widespread. In the present case, the usefulness of liver and hepatobiliary scintigraphy for the diagnosis of liver malformation is described.

  19. Clinical Validation of 4-Dimensional Computed Tomography Ventilation With Pulmonary Function Test Data

    SciTech Connect

    Brennan, Douglas; Schubert, Leah; Diot, Quentin; Castillo, Richard; Castillo, Edward; Guerrero, Thomas; Martel, Mary K.; Linderman, Derek; Gaspar, Laurie E.; Miften, Moyed; Kavanagh, Brian D.; Vinogradskiy, Yevgeniy

    2015-06-01

    Purpose: A new form of functional imaging has been proposed in the form of 4-dimensional computed tomography (4DCT) ventilation. Because 4DCTs are acquired as part of routine care for lung cancer patients, calculating ventilation maps from 4DCTs provides spatial lung function information without added dosimetric or monetary cost to the patient. Before 4DCT-ventilation is implemented it needs to be clinically validated. Pulmonary function tests (PFTs) provide a clinically established way of evaluating lung function. The purpose of our work was to perform a clinical validation by comparing 4DCT-ventilation metrics with PFT data. Methods and Materials: Ninety-eight lung cancer patients with pretreatment 4DCT and PFT data were included in the study. Pulmonary function test metrics used to diagnose obstructive lung disease were recorded: forced expiratory volume in 1 second (FEV1) and FEV1/forced vital capacity. Four-dimensional CT data sets and spatial registration were used to compute 4DCT-ventilation images using a density change–based and a Jacobian-based model. The ventilation maps were reduced to single metrics intended to reflect the degree of ventilation obstruction. Specifically, we computed the coefficient of variation (SD/mean), ventilation V20 (volume of lung ≤20% ventilation), and correlated the ventilation metrics with PFT data. Regression analysis was used to determine whether 4DCT ventilation data could predict for normal versus abnormal lung function using PFT thresholds. Results: Correlation coefficients comparing 4DCT-ventilation with PFT data ranged from 0.63 to 0.72, with the best agreement between FEV1 and coefficient of variation. Four-dimensional CT ventilation metrics were able to significantly delineate between clinically normal versus abnormal PFT results. Conclusions: Validation of 4DCT ventilation with clinically relevant metrics is essential. We demonstrate good global agreement between PFTs and 4DCT-ventilation, indicating that 4DCT-ventilation

  20. Pressure versus volume controlled modes in invasive mechanical ventilation.

    PubMed

    Garnero, A J; Abbona, H; Gordo-Vidal, F; Hermosa-Gelbard, C

    2013-05-01

    The first generation of mechanical ventilators were controlled and cycled by pressure. Unfortunately, they did not allow control of the delivered tidal volume under changes in the dynamics of the respiratory system. This led to a second generation of ventilators that allowed volume control, hence favoring the ventilatory strategy based on normalization of the arterial gases. Studies conducted in the 1980s which related lung injury to the high ventilator pressures utilized while treating acute respiratory distress syndrome patients renewed interest in pressure-controlled mechanical ventilation. In addition, new evidence became available, leading to the development of pulmonary protective strategies aiming at preventing the progression of ventilator-induced lung injury. This review provides a detailed description of the control of pressure or volume using certain ventilatory modes, and offers a general view of their advantages and disadvantages, based on the latest available evidence.

  1. Pressure versus volume controlled modes in invasive mechanical ventilation.

    PubMed

    Garnero, A J; Abbona, H; Gordo-Vidal, F; Hermosa-Gelbard, C

    2013-05-01

    The first generation of mechanical ventilators were controlled and cycled by pressure. Unfortunately, they did not allow control of the delivered tidal volume under changes in the dynamics of the respiratory system. This led to a second generation of ventilators that allowed volume control, hence favoring the ventilatory strategy based on normalization of the arterial gases. Studies conducted in the 1980s which related lung injury to the high ventilator pressures utilized while treating acute respiratory distress syndrome patients renewed interest in pressure-controlled mechanical ventilation. In addition, new evidence became available, leading to the development of pulmonary protective strategies aiming at preventing the progression of ventilator-induced lung injury. This review provides a detailed description of the control of pressure or volume using certain ventilatory modes, and offers a general view of their advantages and disadvantages, based on the latest available evidence. PMID:23260264

  2. Ventilation via Cut Nasotracheal Tube During General Anesthesia

    PubMed Central

    Asahi, Yoshinao; Omichi, Shiro; Adachi, Seita; Kagamiuchi, Hajime; Kotani, Junichiro

    2013-01-01

    Many patients with disabilities need recurrent dental treatment under general anesthesia because of high caries prevalence and the nature of dental treatment. We evaluated the use of a nasal device as a possible substitute for flexible laryngeal mask airway to reduce the risk of unexpected failure accompanying intubation; we succeeded in ventilating the lungs with a cut nasotracheal tube (CNT) with its tip placed in the pharynx. We hypothesized that this technique would be useful during dental treatment under general anesthesia and investigated its usefulness as part of a minimally invasive technique. A prospective study was designed using general anesthesia in 37 dental patients with disabilities such as intellectual impairment, autism, and cerebral palsy. CNT ventilation was compared with mask ventilation with the patient in 3 positions: the neck in flexion, horizontal position, and in extension. The effect of mouth gags was also recorded during CNT ventilation. The percentages of cases with effective ventilation were similar for the 2 techniques in the neck extension and horizontal positions (89.2–97.3%). However, CNT ventilation was significantly more effective than mask ventilation in the neck flexion position (94.6 vs 45.9%; P < .0001). Mouth gags slightly reduced the rate of effective ventilation in the neck flexion position. Most dental treatments involving minor oral surgeries were performed using mouth gags during CNT ventilation. CNT ventilation was shown to be superior to mask ventilation and is useful during dental treatment under general anesthesia. PMID:23506278

  3. Is there still a role for high-frequency oscillatory ventilation in neonates, children and adults?

    PubMed

    Hupp, Susan R; Turner, David A; Rehder, Kyle J

    2015-10-01

    Critically ill patients with respiratory pathology often require mechanical ventilation and while low tidal volume ventilation has become the mainstay of treatment, achieving adequate gas exchange may not be attainable with conventional ventilator modalities. In attempt to achieve gas exchange goals and also mitigate lung injury, high frequency ventilation is often implemented which couples low tidal volumes with sustained mean airway pressure. This manuscript presents the physiology of high-frequency oscillatory ventilation, reviews the currently available data on its use and provides strategies and approaches for this mode of ventilation. PMID:26290121

  4. Combined gated cardiac blood pool scintigraphy and /sup 67/Ga-citrate scintigraphy for detection of cardiac lymphoproliferative disorders

    SciTech Connect

    Winzelberg, G.G.; Rapoport, F.; Boucher, C.A.

    1981-10-01

    Two cases are reported in which combined radionuclide imaging using gated cardiac blood pool scintigraphy and /sup 67/Ga-citrate scintigraphy aided in evaluating lymphomatous involvement of the heart and distinguishing tumor involvement from other cardiac disorders.

  5. Nasal mask ventilation is better than face mask ventilation in edentulous patients

    PubMed Central

    Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

    2016-01-01

    Background and Aims: Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Material and Methods: Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. Results: A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Conclusion: Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients. PMID:27625477

  6. Nasal mask ventilation is better than face mask ventilation in edentulous patients

    PubMed Central

    Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

    2016-01-01

    Background and Aims: Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Material and Methods: Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. Results: A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Conclusion: Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients.

  7. Simple, Inexpensive Model Spirometer for Understanding Ventilation Volumes

    ERIC Educational Resources Information Center

    Giuliodori, Mauricio J.; DiCarlo, Stephen E.

    2004-01-01

    Spirometers are useful for enhancing students' understanding of normal lung volumes, capacities, and flow rates. Spirometers are also excellent for understanding how lung diseases alter ventilation volumes. However, spirometers are expensive, complex, and not appropriate for programs with limited space and budgets. Therefore, we developed a…

  8. Hysterosalpingo-radionuclide scintigraphy (HERS)

    SciTech Connect

    Iturralde, M.; Venter, P.F.

    1981-10-01

    A radionuclide procedure, hysterosalpingo-radionuclide scintigraphy (HERS), was designed to evaluate the migration of a particulate radioactive tracer from the vagina to the peritoneal cavity and ovaries as well as to image and functionally outline the patency of the pathways between these two extremes of the female reproductive system. Technetium-99m human albumin microspheres (99mTc-HAM) were deposited in the posterior fornices of patients who were divided into two specific groups. Group I consisted of patients who were to undergo different elective gynecologic operations, in which besides obtaining sequential images, radioactivity levels were measured in the removed organs and tissues. Group II consisted of patients referred by the Infertility Clinic for evaluation of their reproductive system pathways patency. In this latter group, HERS was compared with contrast hysterosalpingography (HSG) and peritoneoscopy (PCP). The results obtained from measurements of radioactivity levels on the removed surgical specimens and comparison with other conventional gynecologic diagnostic procedures provide accurate evidence of the migration of 99mTc-HAM from the vagina, through the uterus and tubes, to the peritoneal cavity and ovaries, and show that HERS is a simple noninvasive method for functionally imaging and assessing the patency of the female reproductive system pathways.

  9. Pulmonary hyperinflation. A form of barotrauma during mechanical ventilation.

    PubMed

    Baeza, O R; Wagner, R B; Lowery, B D

    1975-11-01

    Barotrauma has been used to describe several specific complications related to mechanical ventilation. These include tension lung cyst, pneumothorax, pneumomediastinum, pneumoperitoneum, and subcutaneous emphysema. Pulmonary hyperinflation, another such complication, occurred in 6 patients, being fatal in 3. Two pathophysiologic mechanisms are discussed. The simpler, and well-recognized, ball-valve airway obstruction allows inspiration of air delivered by the mechanical ventilator but prevents expiration. A more complex circumstance exists when pulmonary contusion or infiltration produces differential lung compliances. This allows extreme hyperinflation of areas of normal lung during attempts to ventilate abnormal lung of low compliance. This mechanism is particularly evident when positive end-expiratory pressure (PEEP) is used in an attempt to open collapsed ventilatory units. Functional complications of lung hyperinflation include decreased alveolar ventilation and compression effects on adjacent structures. Interference with and shifts of regional lung perfusion may worsen gas exchange. Proper treatment includes airway clearance by bronchoscopy, the judicious use of bronchodilators, the discontinuance of PEEP, and adjustments of mechanical ventilators to prevent high airway pressures.

  10. Findings of Bone Scintigraphy After Leech Theraphy

    PubMed Central

    Özyurt, Sinem; Koca, Gökhan; Demirel, Koray; Baskın, Aylin; Korkmaz, Meliha

    2014-01-01

    In this case report, we present a 70 year old female patient who had recieved Leech therapy (hirudotherapy) on her leg without informing referring physician. In dynamic bone scintigraphy there was increased perfusion and hyperemia in her left ankle and leg, also in late static images moderate increased uptake was seen in soft tissue region and at the fracture site of ankle. We learned that she had Leech therapy applied on her leg, which could explain the increased perfusion and hyperemia in dynamic and blood pool phases of bone scintigraphy because of Leech therapy’s dilatory effects on superficial veins. Leech therapy may lead to an increase in perfusion and hyperemia in blood pool phase of bone scintigraphy, which may cause confusion in differential diagnosis. To our best knowledge this report is the first case that shows the scintigraphic findigs after Leech therapy. Conflict of interest:None declared. PMID:24653932

  11. VENTILATION MODEL REPORT

    SciTech Connect

    V. Chipman

    2002-10-31

    The purpose of the Ventilation Model is to simulate the heat transfer processes in and around waste emplacement drifts during periods of forced ventilation. The model evaluates the effects of emplacement drift ventilation on the thermal conditions in the emplacement drifts and surrounding rock mass, and calculates the heat removal by ventilation as a measure of the viability of ventilation to delay the onset of peak repository temperature and reduce its magnitude. The heat removal by ventilation is temporally and spatially dependent, and is expressed as the fraction of heat carried away by the ventilation air compared to the fraction of heat produced by radionuclide decay. One minus the heat removal is called the wall heat fraction, or the remaining amount of heat that is transferred via conduction to the surrounding rock mass. Downstream models, such as the ''Multiscale Thermohydrologic Model'' (BSC 2001), use the wall heat fractions as outputted from the Ventilation Model to initialize their postclosure analyses.

  12. Topographic distribution of pulmonary ventilation and perfusion in the horse

    SciTech Connect

    Amis, T.C.; Pascoe, J.R.; Hornof, W.

    1984-08-01

    The regional distribution of ventilation to perfusion ratios (VA/Q) in the lungs of 8 healthy standing Thoroughbred geldings (4.4 +/- 1.5 years, 465.7 +/- 46.6 kg) was studied, using steady-state inhalation and IV infusion of the radioactive gas krypton-81m. The VA/Q was uniformly distributed within a vertical lung strip centered over the 9th rib on the right side. Ventilation per unit of alveolar volume (V/VA) assessed from the clearance of inhaled radioactive gas in 5 horses increased from 0.49 +/- 0.13 (arbitrary units) in nondependent lung zones to 1.45 +/- 0.16 in dependent lung zones. Seemingly, a vertical gradient of pulmonary ventilation exists in the horse that is matched by a similar gradient of perfusion.

  13. Incidental Warthin Tumor on Pertechnetate Scintigraphy.

    PubMed

    Kulkarni, Mukta; Shetkar, Shubhangi; Joshi, Prathamesh; Kasaliwal, Sanket; Chaudhari, Shrikant

    2016-09-01

    A 30-year-old woman underwent Tc-pertechnetate scintigraphy for evaluation of thyrotoxicosis. The scintigraphy revealed hypervascular thyroid gland with markedly increased trapping function in both the lobes suggesting diagnosis of Graves disease. Incidentally, a hypervascular and pertechnetate avid focus was seen along the lateral margin of the right parotid gland. Pertechnetate avidity and site of uptake suggested possibility of Warthin tumor. Clinical examination and ultrasonography revealed a well-defined lesion in the superficial lobe of the right parotid gland favoring diagnosis of benign lesion. Postsurgery specimen confirmed diagnosis of Warthin tumor. PMID:27405035

  14. Guidelines for radioiodinated MIBG scintigraphy in children.

    PubMed

    Olivier, Pierre; Colarinha, Paula; Fettich, Jure; Fischer, Sibylle; Frökier, Jörgen; Giammarile, Francesco; Gordon, Isky; Hahn, Klaus; Kabasakal, Levent; Mann, Mike; Mitjavila, Mercedes; Piepsz, Amy; Porn, Ute; Sixt, Rune; van Velzen, Jeannette

    2003-05-01

    These guidelines on the use of radioiodinated (99m)Tc-MIBG scintigraphy in children, which summarise the views of the Paediatric Committee of the European Association of Nuclear Medicine, provide a framework which may prove helpful to nuclear medicine teams in daily practice. They have been influenced by the conclusions of the "Consensus Guidelines for MIBG Scintigraphy" (Paris, November 6, 1997) of the European Neuroblastoma Group and by those of the Oncological Committee of the French Society of Nuclear Medicine. The guidelines should be taken in the context of "good practice" and any local/national rules which apply to nuclear medicine examinations. PMID:12658506

  15. Guidelines for radioiodinated MIBG scintigraphy in children.

    PubMed

    Olivier, Pierre; Colarinha, Paula; Fettich, Jure; Fischer, Sibylle; Frökier, Jörgen; Giammarile, Francesco; Gordon, Isky; Hahn, Klaus; Kabasakal, Levent; Mann, Mike; Mitjavila, Mercedes; Piepsz, Amy; Porn, Ute; Sixt, Rune; van Velzen, Jeannette

    2003-05-01

    These guidelines on the use of radioiodinated (99m)Tc-MIBG scintigraphy in children, which summarise the views of the Paediatric Committee of the European Association of Nuclear Medicine, provide a framework which may prove helpful to nuclear medicine teams in daily practice. They have been influenced by the conclusions of the "Consensus Guidelines for MIBG Scintigraphy" (Paris, November 6, 1997) of the European Neuroblastoma Group and by those of the Oncological Committee of the French Society of Nuclear Medicine. The guidelines should be taken in the context of "good practice" and any local/national rules which apply to nuclear medicine examinations.

  16. VENTILATION TECHNOLOGY SYSTEMS ANALYSIS

    EPA Science Inventory

    The report gives results of a project to develop a systems analysis of ventilation technology and provide a state-of-the-art assessment of ventilation and indoor air quality (IAQ) research needs. (NOTE: Ventilation technology is defined as the hardware necessary to bring outdoor ...

  17. Ventilator versus manual hyperinflation in clearing sputum in ventilated intensive care unit patients.

    PubMed

    Dennis, Diane; Jacob, Wendy; Budgeon, Charley

    2012-01-01

    The aim of hyperinflation in the ventilated intensive care unit patient is to increase oxygenation, reverse lung collapse and clear sputum. The efficacy and consistency of manual hyperventilation is well supported in the literature, but there is limited published evidence supporting hyperventilation utilising a ventilator. Despite this, a recent survey established that almost 40% of Australian tertiary intensive care units utilise ventilator hyperinflation. The aim of this non-inferiority cross-over study was to determine whether ventilator hyperinflation was as effective as manual hyperinflation in clearing sputum from patients receiving mechanical ventilation using a prescriptive ventilator hyperinflation protocol. Forty-six patients received two randomly ordered physiotherapy treatments on the same day by the same physiotherapist. The efficacy of the hyperinflation modes was measured by sputum wet weight. Secondary measures included compliance, tidal volume, airway pressure and PaO2/FiO2 ratio. There was no difference in wet weight of sputum cleared using ventilator hyperinflation or manual hyperinflation (mean 3.2 g, P=0.989). Further, no difference in compliance (P=0.823), tidal volume (P=0.219), heart rate (P=0.579), respiratory rate (P=0.929) or mean arterial pressure (P=0.593) was detected. A statistically significant difference was seen in mean airway pressure (P=0.002) between techniques. The effect of techniques on the PaO2/FiO2 response ratio was dependent on time (interaction P=0.024). Physiotherapy using ventilator hyperinflation cleared a comparable amount of sputum and was as safe as manual hyperinflation. This research describes a ventilator hyperinflation protocol that will serve as a platform for continued discussion, research and development of its application in ventilated patients.

  18. The performance of Dräger Oxylog ventilators at simulated altitude.

    PubMed

    Flynn, J G; Singh, B

    2008-07-01

    Ventilated patients frequently require transport by air in a hypobaric environment. Previous studies have demonstrated significant changes in the performance of ventilators with changes in cabin pressure (altitude) but no studies have been published on the function of modem ventilators at altitude. This experiment set out to evaluate ventilatory parameters (tidal volume and respiratory rate) of three commonly used transport ventilators (the Dräger Oxylog 1000, 2000 and 3000) in a simulated hypobaric environment. Ventilators were assessed using either air-mix (60% oxygen) or 100% oxygen and tested against models simulating a normal lung, a low compliance (Acute Respiratory Distress Syndrome) lung and a high-resistance (asthma) lung. Ventilators were tested at a range of simulated altitudes between sea level and 3048 m. Over this range, tidal volume delivered by the Oxylog 1000 increased by 68% and respiratory rate decreased by 28%. Tidal volume delivered by the Oxylog 2000 ventilator increased by 29% over the same range of altitudes but there was no significant change in respiratory rate. Tidal volume and respiratory rate remained constant with the Oxylog 3000 over the same range of altitudes. Changes were consistent with each ventilator regardless of oxygen content or lung model. It is important that clinicians involved in critical care transport in a hypobaric environment are aware that individual ventilators perform differently at altitude and that they are aware of the characteristics of the particular ventilator that they are using. PMID:18714624

  19. Regional fractional ventilation mapping in spontaneously breathing mice using hyperpolarized ¹²⁹Xe MRI.

    PubMed

    Imai, Hirohiko; Matsumoto, Hironobu; Miyakoshi, Erika; Okumura, Shintaro; Fujiwara, Hideaki; Kimura, Atsuomi

    2015-01-01

    The feasibility of ventilation imaging with hyperpolarized (HP) (129) Xe MRI has been investigated for quantitative and regional assessment of ventilation in spontaneously breathing mice. The multiple breath ventilation imaging technique was modified to the protocol of spontaneous inhalation of HP (129) Xe delivered continuously from a (129) Xe polarizer. A series of (129) Xe ventilation images was obtained by varying the number of breaths before the (129) Xe lung imaging. The fractional ventilation, r, was successfully evaluated for spontaneously breathing mice. An attempt was made to detect ventilation dysfunction in the emphysematous mouse lung induced by intratracheal administration of porcine pancreatic elastase (PPE). As a result, the distribution of fractional ventilation could be visualized by the r map. Significant dysfunction of ventilation was quantitatively identified in the PPE-treated group. The whole-lung r value of 0.34 ± 0.01 for control mice (N = 4) was significantly reduced, to 0.25 ± 0.07, in PPE-treated mice (N = 4) (p = 0.038). This study is the first application of multiple breath ventilation imaging to spontaneously breathing mice, and shows that this methodology is sensitive to differences in the pulmonary ventilation. This methodology is expected to improve simplicity as well as noninvasiveness when assessing regional ventilation in small rodents.

  20. Respirator triggering of electron-beam computed tomography (EBCT): differences in dynamic changes between augmented ventilation and controlled mechanical ventilation

    NASA Astrophysics Data System (ADS)

    Recheis, Wolfgang A.; Kleinsasser, Axel; Schuster, Antonius H.; Loeckinger, Alexander; Frede, Thomas; Springer, Peter; Hoermann, Christoph; zur Nedden, Dieter

    2000-04-01

    The purpose was to evaluate differences in dynamic changes of the lung aeration (air-tissue ratio) between augmented modes of ventilation (AMV) and controlled mechanical ventilation (CMV) in normal subjects. 4 volunteers, ventilated with the different respirator protocols via face mask, were scanned using the EBCT in the 50 ms mode. A software analyzed the respirator's digitized pressure and volume signals of two subsequent ventilation phases. Using these values it was possible to calculate the onset of inspiration or expiration of the next respiratory phase. The calculated starting point was then used to trigger the EBCT. The dynamic changes of air- tissue ratios were evaluated in three separate regions: a ventral, an intermediate and a dorsal area. AMV results in increase of air-tissue ratio in the dorsal lung area due to the active contraction of the diaphragm, whereas CMV results in a more pronounced increase in air-tissue ratio of the ventral lung area. This study gives further insight into the dynamic changes of the lung's biomechanics by comparing augmented ventilation and controlled mechanical ventilation in the healthy proband.

  1. Gas exchange and intrapulmonary distribution of ventilation during continuous-flow ventilation

    SciTech Connect

    Vettermann, J.; Brusasco, V.; Rehder, K.

    1988-05-01

    In 12 anesthetized paralyzed dogs, pulmonary gas exchange and intrapulmonary inspired gas distribution were compared between continuous-flow ventilation (CFV) and conventional mechanical ventilation (CMV). Nine dogs were studied while they were lying supine, and three dogs were studied while they were lying prone. A single-lumen catheter for tracheal insufflation and a double-lumen catheter for bilateral endobronchial insufflation (inspired O2 fraction = 0.4; inspired minute ventilation = 1.7 +/- 0.3 (SD) 1.kg-1.min-1) were evaluated. Intrapulmonary gas distribution was assessed from regional 133Xe clearances. In dogs lying supine, CO2 elimination was more efficient with endobronchial insufflation than with tracheal insufflation, but the alveolar-arterial O2 partial pressure difference was larger during CFV than during CMV, regardless of the type of insufflation. By contrast, endobronchial insufflation maintained both arterial PCO2 and alveolar-arterial O2 partial pressure difference at significantly lower levels in dogs lying prone than in dogs lying supine. In dogs lying supine, the dependent lung was preferentially ventilated during CMV but not during CFV. In dogs lying prone, gas distribution was uniform with both modes of ventilation. The alveolar-arterial O2 partial pressure difference during CFV in dogs lying supine was negatively correlated with the reduced ventilation of the dependent lung, which suggests that increased ventilation-perfusion mismatching was responsible for the increase in alveolar-arterial O2 partial pressure difference. The more efficient oxygenation during CFV in dogs lying prone suggests a more efficient matching of ventilation to perfusion, presumably because the distribution of blood flow is also nearly uniform.

  2. DEMAND CONTROLLED VENTILATION AND CLASSROOM VENTILATION

    SciTech Connect

    Fisk, William J.; Mendell, Mark J.; Davies, Molly; Eliseeva, Ekaterina; Faulkner, David; Hong, Tienzen; Sullivan, Douglas P.

    2014-01-06

    This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling. Major findings included: ? The single-location carbon dioxide sensors widely used for demand controlled ventilation frequently have large errors and will fail to effectively control ventilation rates (VRs).? Multi-location carbon dioxide measurement systems with more expensive sensors connected to multi-location sampling systems may measure carbon dioxide more accurately.? Currently-available optical people counting systems work well much of the time but have large counting errors in some situations. ? In meeting rooms, measurements of carbon dioxide at return-air grilles appear to be a better choice than wall-mounted sensors.? In California, demand controlled ventilation in general office spaces is projected to save significant energy and be cost effective only if typical VRs without demand controlled ventilation are very high relative to VRs in codes. Based on the research, several recommendations were developed for demand controlled ventilation specifications in the California Title 24 Building Energy Efficiency Standards.The research on classroom ventilation collected data over two years on California elementary school classrooms to investigate associations between VRs and student illness absence (IA). Major findings included: ? Median classroom VRs in all studied climate zones were below the California guideline, and 40percent lower in portable than permanent buildings.? Overall, one additional L/s per person of VR was associated with 1.6percent less IA. ? Increasing average VRs in California K-12 classrooms from the current average to the required level is estimated to decrease IA by 3.4percent, increasing State attendance-based funding to school districts by $33M, with $6.2 M in increased energy costs. Further VR increases would provide additional benefits

  3. Daytime mechanical ventilation in chronic respiratory insufficiency.

    PubMed

    Schönhofer, B; Geibel, M; Sonneborn, M; Haidl, P; Köhler, D

    1997-12-01

    Chronic respiratory insufficiency (CRI) is associated with nocturnal hypoventilation. Treatment with noninvasive mechanical ventilation (NIMV) performed overnight relieves symptoms of hypoventilation and improves daytime blood gases in CRI. In order to test whether the efficacy of NIMV depends on it being applied during sleep, we conducted a prospective case-controlled study comparing daytime mechanical ventilation (dMV) in awake patients with nocturnal mechanical ventilation (nMV) given in equal quantities. We enrolled 34 clinically stable patients (age 56.1+/-12.1 yrs, 20 females, 14 males) with CRI due to restrictive lung and chest wall disorders and neuromuscular disease. Using a prospective case-control design, matched subjects were allocated alternately to dMV and nMV. After 1 month of NIMV there was considerable symptomatic improvement in both dMV and nMV patients. There were no significant differences between groups in the improvement in daytime arterial carbon dioxide tension (Pa,CO2) (dMV from 7.5+/-0.6 to 5.7+/-0.6 kPa; nMV from 7.2+/-0.5 to 5.8+/-0.5 kPa, p<0.0001) and during the unassisted spontaneous night-time ventilation in terms of transcutaneous Pa,CO2 (dMV from 8.4+/-1.2 to 6.6+/-0.7 kPa; nMV from 8.2+/-1.2 to 6.8+/-0.5 kPa, p<0.0001). We conclude that in many respects, when compared to nocturnal mechanical ventilation, daytime mechanical ventilation in awake patients is equally effective at reversing chronic respiratory insufficiency. Since long-term safety issues were not addressed in this study, we recommend that nocturnal mechanical ventilation should remain the modality of choice for noninvasive mechanical ventilation.

  4. Radionuclide assessment of the effects of chest physical therapy on ventilation in cystic fibrosis

    SciTech Connect

    DeCesare, J.A.; Babchyck, B.M.; Colten, H.R.; Treves, S.

    1982-06-01

    This study assesses the use of /sup 81m/Kr scintigraphy as a measurement tool in evaluating the effectiveness of bronchial drainage with percussion and vibration on peripheral ventilation in patients with cystic fibrosis. Ten patients with cystic fibrosis participated. Each patient underwent a /sup 81m/Kr ventilation study and traditional pulmonary function tests. Forty-five minutes later, these studies were repeated before and after a chest physical therapy treatment. Each patient acted as his own control. All /sup 81m/Kr scintiscans were recorded and analyzed visually and numerically using a digital computer to assess distribution of ventilation. Visual analysis of the scintiscans indicated individual variation in treatment response: in some patients ventilation improved with therapy; in others, no change was noted; still others had changes independent of treatment. Numerical data derived from the scintiscans and pulmonary function tests showed no important differences among the three studies of each patient. Airway abnormalities characteristic of cystic fibrosis, progression of the disease, sputum production, or a combination of these factors may account for the individual variation in response to treatment. /sup 81m/Kr scintigraphy is a reliable measure of regional ventilation and should be useful for assessing the efficacy of chest physical therapy because of the consistent, high quality visual data retrieved.

  5. Flow measurement in mechanical ventilation: a review.

    PubMed

    Schena, Emiliano; Massaroni, Carlo; Saccomandi, Paola; Cecchini, Stefano

    2015-03-01

    Accurate monitoring of flow rate and volume exchanges is essential to minimize ventilator-induced lung injury. Mechanical ventilators employ flowmeters to estimate the amount of gases delivered to patients and use the flow signal as a feedback to adjust the desired amount of gas to be delivered. Since flowmeters play a crucial role in this field, they are required to fulfill strict criteria in terms of dynamic and static characteristics. Therefore, mechanical ventilators are equipped with only the following kinds of flowmeters: linear pneumotachographs, fixed and variable orifice meters, hot wire anemometers, and ultrasonic flowmeters. This paper provides an overview of these sensors. Their working principles are described together with their relevant advantages and disadvantages. Furthermore, the most promising emerging approaches for flowmeters design (i.e., fiber optic technology and three dimensional micro-fabrication) are briefly reviewed showing their potential for this application. PMID:25659299

  6. TH-E-BRF-02: 4D-CT Ventilation Image-Based IMRT Plans Are Dosimetrically Comparable to SPECT Ventilation Image-Based Plans

    SciTech Connect

    Kida, S; Bal, M; Kabus, S; Loo, B; Keall, P; Yamamoto, T

    2014-06-15

    Purpose: An emerging lung ventilation imaging method based on 4D-CT can be used in radiotherapy to selectively avoid irradiating highly-functional lung regions, which may reduce pulmonary toxicity. Efforts to validate 4DCT ventilation imaging have been focused on comparison with other imaging modalities including SPECT and xenon CT. The purpose of this study was to compare 4D-CT ventilation image-based functional IMRT plans with SPECT ventilation image-based plans as reference. Methods: 4D-CT and SPECT ventilation scans were acquired for five thoracic cancer patients in an IRB-approved prospective clinical trial. The ventilation images were created by quantitative analysis of regional volume changes (a surrogate for ventilation) using deformable image registration of the 4D-CT images. A pair of 4D-CT ventilation and SPECT ventilation image-based IMRT plans was created for each patient. Regional ventilation information was incorporated into lung dose-volume objectives for IMRT optimization by assigning different weights on a voxel-by-voxel basis. The objectives and constraints of the other structures in the plan were kept identical. The differences in the dose-volume metrics have been evaluated and tested by a paired t-test. SPECT ventilation was used to calculate the lung functional dose-volume metrics (i.e., mean dose, V20 and effective dose) for both 4D-CT ventilation image-based and SPECT ventilation image-based plans. Results: Overall there were no statistically significant differences in any dose-volume metrics between the 4D-CT and SPECT ventilation imagebased plans. For example, the average functional mean lung dose of the 4D-CT plans was 26.1±9.15 (Gy), which was comparable to 25.2±8.60 (Gy) of the SPECT plans (p = 0.89). For other critical organs and PTV, nonsignificant differences were found as well. Conclusion: This study has demonstrated that 4D-CT ventilation image-based functional IMRT plans are dosimetrically comparable to SPECT ventilation image

  7. Humidification during invasive and noninvasive mechanical ventilation: 2012.

    PubMed

    Restrepo, Ruben D; Walsh, Brian K

    2012-05-01

    We searched the MEDLINE, CINAHL, and Cochrane Library databases for articles published between January 1990 and December 2011. The update of this clinical practice guideline is based on 184 clinical trials and systematic reviews, and 10 articles investigating humidification during invasive and noninvasive mechanical ventilation. The following recommendations are made following the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) scoring system: 1. Humidification is recommended on every patient receiving invasive mechanical ventilation. 2. Active humidification is suggested for noninvasive mechanical ventilation, as it may improve adherence and comfort. 3. When providing active humidification to patients who are invasively ventilated, it is suggested that the device provide a humidity level between 33 mg H(2)O/L and 44 mg H(2)O/L and gas temperature between 34°C and 41°C at the circuit Y-piece, with a relative humidity of 100%. 4. When providing passive humidification to patients undergoing invasive mechanical ventilation, it is suggested that the HME provide a minimum of 30 mg H(2)O/L. 5. Passive humidification is not recommended for noninvasive mechanical ventilation. 6. When providing humidification to patients with low tidal volumes, such as when lung-protective ventilation strategies are used, HMEs are not recommended because they contribute additional dead space, which can increase the ventilation requirement and P(aCO(2)). 7. It is suggested that HMEs are not used as a prevention strategy for ventilator-associated pneumonia.

  8. Protective garment ventilation system

    NASA Technical Reports Server (NTRS)

    Lang, R. (Inventor)

    1970-01-01

    A method and apparatus for ventilating a protective garment, space suit system, and/or pressure suits to maintain a comfortable and nontoxic atmosphere within is described. The direction of flow of a ventilating and purging gas in portions of the garment may be reversed in order to compensate for changes in environment and activity of the wearer. The entire flow of the ventilating gas can also be directed first to the helmet associated with the garment.

  9. DECT Ventilation Imaging

    ClinicalTrials.gov

    2015-08-06

    For Oncologic Patients :; Potentially Operable Lung Tumor; With a Recent (Less Than 1 Month) V/Q Scan; For Lung Transplant Recipients :; Single of Bilateral Lung Transplant; From 5 Months Onwards; With Recent (Less Than 1 Month) Respiratory Functional Explorations

  10. Radioiodine therapy of hyperthyroidism precludes thallium-201 myocardial scintigraphy

    SciTech Connect

    Orzel, J.A.; Kruyer, W.B.; Borchert, R.D.

    1987-02-01

    The authors attempted to perform Tl-201 myocardial perfusion scintigraphy in a 42-year-old man 23 and 35 days after he received 9.8 mCi of oral I-131 for documented Graves' disease. Interference from primary and scattered photons from residual thyroid I-131 made Tl-201 myocardial scintigraphy technically impossible. A series of phantom and patient studies using I-131 and Tl-201 were performed, yielding guidelines for planning Tl-201 myocardial scintigraphy following radioiodine therapy.

  11. A prototype of volume-controlled tidal liquid ventilator using independent piston pumps.

    PubMed

    Robert, Raymond; Micheau, Philippe; Cyr, Stéphane; Lesur, Olivier; Praud, Jean-Paul; Walti, Hervé

    2006-01-01

    Liquid ventilation using perfluorochemicals (PFC) offers clear theoretical advantages over gas ventilation, such as decreased lung damage, recruitment of collapsed lung regions, and lavage of inflammatory debris. We present a total liquid ventilator designed to ventilate patients with completely filled lungs with a tidal volume of PFC liquid. The two independent piston pumps are volume controlled and pressure limited. Measurable pumping errors are corrected by a programmed supervisor module, which modifies the inserted or withdrawn volume. Pump independence also allows easy functional residual capacity modifications during ventilation. The bubble gas exchanger is divided into two sections such that the PFC exiting the lungs is not in contact with the PFC entering the lungs. The heating system is incorporated into the metallic base of the gas exchanger, and a heat-sink-type condenser is placed on top of the exchanger to retrieve PFC vapors. The prototype was tested on 5 healthy term newborn lambs (<5 days old). The results demonstrate the efficiency and safety of the prototype in maintaining adequate gas exchange, normal acido-basis equilibrium, and cardiovascular stability during a short, 2-hour total liquid ventilator. Airway pressure, lung volume, and ventilation scheme were maintained in the targeted range.

  12. A prototype of volume-controlled tidal liquid ventilator using independent piston pumps.

    PubMed

    Robert, Raymond; Micheau, Philippe; Cyr, Stéphane; Lesur, Olivier; Praud, Jean-Paul; Walti, Hervé

    2006-01-01

    Liquid ventilation using perfluorochemicals (PFC) offers clear theoretical advantages over gas ventilation, such as decreased lung damage, recruitment of collapsed lung regions, and lavage of inflammatory debris. We present a total liquid ventilator designed to ventilate patients with completely filled lungs with a tidal volume of PFC liquid. The two independent piston pumps are volume controlled and pressure limited. Measurable pumping errors are corrected by a programmed supervisor module, which modifies the inserted or withdrawn volume. Pump independence also allows easy functional residual capacity modifications during ventilation. The bubble gas exchanger is divided into two sections such that the PFC exiting the lungs is not in contact with the PFC entering the lungs. The heating system is incorporated into the metallic base of the gas exchanger, and a heat-sink-type condenser is placed on top of the exchanger to retrieve PFC vapors. The prototype was tested on 5 healthy term newborn lambs (<5 days old). The results demonstrate the efficiency and safety of the prototype in maintaining adequate gas exchange, normal acido-basis equilibrium, and cardiovascular stability during a short, 2-hour total liquid ventilator. Airway pressure, lung volume, and ventilation scheme were maintained in the targeted range. PMID:17117053

  13. Correlation of regional breath sound with regional ventilation in emphysema

    SciTech Connect

    Ploysongsang, Y.; Pare, J.A.; Macklem, P.T.

    1982-09-01

    We measured regional breath sound intensities (Ib) by a microphone amplifier system in 8 subjects with emphysema. We also measured regional white noise transmissions (Tn) from the same areas in all subjects. The recorded areas were 5, 10, 15, and 20 cm from the apex of the lung just lateral to the right anterior midclavicular line. Xenon ventilation indexes (xenon tidal raw counts, an index of total regional ventilation; xenon equilibration raw counts, an index of ventilating lung volume; xenon ventilation per unit volume (Vr), an index of ventilation per unit volume) were also recorded from the same areas. The Ib, Tn, Ib/Tn (an index of sound generation), and xenon ventilation indexes were all expressed as a fraction of the mean value of all four recorded areas. The Ib and Ib/Tn correlated best with the xenon tidal raw counts, correlated well with the xenon equilibration raw counts, and correlated poorly with Vr. We conclude that Ib and Ib/Tn can be used to quantify regional ventilation in subjects with emphysema.

  14. Musculoskeletal scintigraphy of the equine athlete.

    PubMed

    Dyson, Sue

    2014-01-01

    Nuclear scintigraphic examination of equine athletes has a potentially important role in the diagnosis of lameness or poor performance, but increased radiopharmaceutical uptake (IRU) is not necessarily synonymous with pain causing lameness. Nuclear scintigraphy is highly sensitive to changes in bone turnover that may be induced by loading and knowledge of normal patterns of RU is crucial for accurate diagnosis. Blood pool images can be useful for identification of some soft tissue injuries, although acute bone injuries may also have intense IRU in blood pool images. Some muscle injuries may be associated with IRU in bone phase images. The use of scintigraphy together with other diagnostic imaging modalities has helped us to better understand the mechanisms of some musculoskeletal injuries. In immature racehorses, stress-related bone injury is a common finding and may be multifocal, whereas in mature sport horses, a very different spectrum of injuries may be identified. False-negative results are common with some injuries.

  15. Ventilatory failure, ventilator support, and ventilator weaning.

    PubMed

    Tobin, Martin J; Laghi, Franco; Jubran, Amal

    2012-10-01

    The development of acute ventilatory failure represents an inability of the respiratory control system to maintain a level of respiratory motor output to cope with the metabolic demands of the body. The level of respiratory motor output is also the main determinant of the degree of respiratory distress experienced by such patients. As ventilatory failure progresses and patient distress increases, mechanical ventilation is instituted to help the respiratory muscles cope with the heightened workload. While a patient is connected to a ventilator, a physician's ability to align the rhythm of the machine with the rhythm of the patient's respiratory centers becomes the primary determinant of the level of rest accorded to the respiratory muscles. Problems of alignment are manifested as failure to trigger, double triggering, an inflationary gas-flow that fails to match inspiratory demands, and an inflation phase that persists after a patient's respiratory centers have switched to expiration. With recovery from disorders that precipitated the initial bout of acute ventilatory failure, attempts are made to discontinue the ventilator (weaning). About 20% of weaning attempts fail, ultimately, because the respiratory controller is unable to sustain ventilation and this failure is signaled by development of rapid shallow breathing. Substantial advances in the medical management of acute ventilatory failure that requires ventilator assistance are most likely to result from research yielding novel insights into the operation of the respiratory control system. PMID:23720268

  16. Exclusion of pneumothorax by radionuclide lung scan

    SciTech Connect

    Weiss, P.E.

    1986-05-01

    A case is reported in which ventilation lung imaging was useful in excluding a large pneumothorax. This technique may be helpful in patients with emphysema in whom exclusion of pneumothorax by radiographic criteria might be difficult.

  17. Review of Residential Ventilation Technologies

    SciTech Connect

    Armin Rudd

    2005-08-30

    This paper reviews current and potential ventilation technologies for residential buildings, including a variety of mechanical systems, natural ventilation, and passive ventilation. with particular emphasis on North American climates and construction.

  18. Role of scintigraphy in urinary tract infection

    SciTech Connect

    Conway, J.J.

    1988-10-01

    There is controversy regarding the role of radiological imaging for urinary tract infection (UTI). The gold standard has been the intravenous pyelogram (IVP). Yet, the IVP has a very limited value with only about 25% of children with pyelonephritis demonstrating abnormalities. Ultrasound (US) has recently been advocated as a replacement for the poorly sensitive and poorly specific IVP. However, comparative studies between US and IVP indicate only an equivalent sensitivity and specificity. Cortical scintigraphy with Technetium-99m glucoheptonate (99mTc GH) or 99mTc dimercaptosuccinic acid (99mTc DMSA) has also been advocated as a means of differentiating parenchymal (pyelonephritis) from nonparenchymal (lower UTI) involvement in UTI. The clinical presentation may be misleading especially in the infant and child in whom an elevated temperature, flank pain, shaking chills, or an elevated sedimentation rate are often lacking. The clinician attempts to localize the site of infection for it has a direct bearing upon the therapy. A collecting system infection can often be eradicated with a single oral dose of an appropriate antibiotic, whereas renal parenchymal involvement requires IV therapy for an extended interval. Cortical scintigraphy can localize the site of infection with a high degree of accuracy. Recent studies report a sensitivity of 86% and specificity of 81% of pyelonephritis. This is in contrast to the IVP with a sensitivity of only 24% and US with a sensitivity of only 42%. The scintigraphic appearance of parenchymal infection of the kidney is a spectrum of minimal to gross defects reflecting the degree of histologic involvement that spans from a mild infection to frank abscess. Cortical scintigraphy can be used to monitor the evolution of scarring following infection. Cortical scintigraphy with 99mTc DMSA or 99mTc GH is the method of choice for the initial evaluation of UTI. 37 references.

  19. Bone scintigraphy in fluoride treated osteoporosis

    SciTech Connect

    Froelich, J.W.; Kleerekoper, M.; Parker, D.A.

    1985-05-01

    Quantitative bone scintigraphy was performed on 23 white females with post-menopausal osteoporosis and vertebral compression fractures. These patients were then entered into a randomized, double-blind clinical trial or sodium fluoride therapy (NaF=14, placebo=9) which included repeat bone scintigraphy every six months. Scintigraphic images were acquired for 500K counts per image over the total body with computer acquisition over the posterior thoracic and lumbar spine. Images were obtained on a wide field-of-view gamma camera two hours after injecting 15 mCi of Tc-99m MDP. Data analysis showed a significant reduction in the activity ratio of abnormal vertebral body to normal vertebral body in those patients treated with sodium fluoride (paired t-test p=0.0095). No significant change was observed in the control group of (p=0.142). These results suggest that sodium fluoride therapy promotes more rapid healing of osteoporotic vertebral fractures. They also demonstrate the utility of serial quantitative bone scintigraphy in assessing osteoporotic patients with vertebral compression fractures.

  20. Guide to Home Ventilation

    SciTech Connect

    2010-10-01

    A fact sheet from the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy: Ventilation refers to the exchange of indoor and outdoor air. Without proper ventilation, an otherwise insulated and airtight house will seal in harmful pollutants, such as carbon monoxide, and moisture that can damage a house.

  1. Multifamily Ventilation Retrofit Strategies

    SciTech Connect

    Ueno, K.; Lstiburek, J.; Bergey, D.

    2012-12-01

    In multifamily buildings, central ventilation systems often have poor performance, overventilating some portions of the building (causing excess energy use), while simultaneously underventilating other portions (causing diminished indoor air quality). BSC and Innova Services Corporation performed a series of field tests at a mid-rise test building undergoing a major energy audit and retrofit, which included ventilation system upgrades.

  2. Plasma-derived human C1-esterase inhibitor does not prevent mechanical ventilation-induced pulmonary complement activation in a rat model of Streptococcus pneumoniae pneumonia.

    PubMed

    de Beer, F M; Aslami, H; Hoeksma, J; van Mierlo, G; Wouters, D; Zeerleder, S; Roelofs, J J T H; Juffermans, N P; Schultz, M J; Lagrand, W K

    2014-11-01

    Mechanical ventilation has the potential to cause lung injury, and the role of complement activation herein is uncertain. We hypothesized that inhibition of the complement cascade by administration of plasma-derived human C1-esterase inhibitor (C1-INH) prevents ventilation-induced pulmonary complement activation, and as such attenuates lung inflammation and lung injury in a rat model of Streptococcus pneumoniae pneumonia. Forty hours after intratracheal challenge with S. pneumoniae causing pneumonia rats were subjected to ventilation with lower tidal volumes and positive end-expiratory pressure (PEEP) or high tidal volumes without PEEP, after an intravenous bolus of C1-INH (200 U/kg) or placebo (saline). After 4 h of ventilation blood, broncho-alveolar lavage fluid and lung tissue were collected. Non-ventilated rats with S. pneumoniae pneumonia served as controls. While ventilation with lower tidal volumes and PEEP slightly amplified pneumonia-induced complement activation in the lungs, ventilation with higher tidal volumes without PEEP augmented local complement activation more strongly. Systemic pre-treatment with C1-INH, however, failed to alter ventilation-induced complement activation with both ventilation strategies. In accordance, lung inflammation and lung injury were not affected by pre-treatment with C1-INH, neither in rats ventilated with lower tidal volumes and PEEP, nor rats ventilated with high tidal volumes without PEEP. Ventilation augments pulmonary complement activation in a rat model of S. pneumoniae pneumonia. Systemic administration of C1-INH, however, does not attenuate ventilation-induced complement activation, lung inflammation, and lung injury. PMID:24760631

  3. Realtime mine ventilation simulation

    SciTech Connect

    McDaniel, K.H.; Wallace, K.G. Jr.

    1997-04-01

    This paper describes the development of a Windows based, interactive mine ventilation simulation software program at the Waste Isolation Pilot Plant (WIPP). To enhance the operation of the underground ventilation system, Westinghouse Electric Corporation developed the program called WIPPVENT. While WIPPVENT includes most of the functions of the commercially available simulation program VNETPC and uses the same subroutine to calculate airflow distributions, the user interface has been completely rewritten as a Windows application with screen graphics. WIPPVENT is designed to interact with WIPP ventilation monitoring systems through the sitewise Central monitoring System. Data can be continuously collected from the Underground Ventilation Remote Monitoring and Control System (e.g., air quantity and differential pressure) and the Mine Weather Stations (psychrometric data). Furthermore, WIPPVENT incorporates regulator characteristic curves specific to the site. The program utilizes this data to create and continuously update a REAL-TIME ventilation model. This paper discusses the design, key features, and interactive capabilities of WIPPVENT.

  4. Percutaneous transtracheal ventilation.

    PubMed

    Smith, R B; Babinski, M; Klain, M; Pfaeffle, H

    1976-10-01

    The technique of percutaneous transtracheal ventilation (intermittent jets of oxygen under high pressure, 50 pounds per square inch [psi]) has been used for resuscitation during anesthesia and prior to tracheostomy, and has been established as an important adjunct to life-support techniques. The technical aspects are described together with experimental evidence that intermittent jet ventilation is necessary to eliminate carbon dioxide. The complications occurring with a series of 80 patients are reported along with experimental work in ventilation of dogs with compressed air sources, including truck tires. Emergency physicians should be familiar with this technique and equipment for its use should be readily available in the emergency department. The potential role of transtracheal ventilation in the mobile intensive care unit at accident sites has been explored and appears promising. Conventional airway support techniques should be applied prior to resorting to transtracheal ventilation.

  5. Non-invasive mechanical ventilation and epidural anesthesia for an emergency open cholecystectomy.

    PubMed

    Yurtlu, Bülent Serhan; Köksal, Bengü; Hancı, Volkan; Turan, Işıl Özkoçak

    2016-01-01

    Non-invasive ventilation is an accepted treatment modality in both acute exacerbations of respiratory diseases and chronic obstructive lung disease. It is commonly utilized in the intensive care units, or for postoperative respiratory support in post-anesthesia care units. This report describes intraoperative support in non-invasive ventilation to neuroaxial anesthesia for an emergency upper abdominal surgery. PMID:27591472

  6. [Non-invasive mechanical ventilation and epidural anesthesia for an emergency open cholecystectomy].

    PubMed

    Yurtlu, Bülent Serhan; Köksal, Bengü; Hancı, Volkan; Turan, Işıl Özkoçak

    2016-01-01

    Non-invasive ventilation is an accepted treatment modality in both acute exacerbations of respiratory diseases and chronic obstructive lung disease. It is commonly utilized in the intensive care units, or for postoperative respiratory support in post-anesthesia care units. This report describes intraoperative support in non-invasive ventilation to neuroaxial anesthesia for an emergency upper abdominal surgery.

  7. Non-invasive mechanical ventilation and epidural anesthesia for an emergency open cholecystectomy.

    PubMed

    Yurtlu, Bülent Serhan; Köksal, Bengü; Hancı, Volkan; Turan, Işıl Özkoçak

    2016-01-01

    Non-invasive ventilation is an accepted treatment modality in both acute exacerbations of respiratory diseases and chronic obstructive lung disease. It is commonly utilized in the intensive care units, or for postoperative respiratory support in post-anesthesia care units. This report describes intraoperative support in non-invasive ventilation to neuroaxial anesthesia for an emergency upper abdominal surgery.

  8. Transpulmonary pressure monitoring during mechanical ventilation: a bench-to-bedside review.

    PubMed

    Mietto, Cristina; Malbrain, Manu L N G; Chiumello, Davide

    2015-01-01

    Different ventilation strategies have been suggested in the past in patients with acute respiratory distress syndrome (ARDS). Airway pressure monitoring alone is inadequate to assure optimal ventilatory support in ARDS patients. The assessment of transpulmonary pressure (PTP) can help clinicians to tailor mechanical ventilation to the individual patient needs. Transpulmonary pressure monitoring, defined as airway pressure (Paw) minus intrathoracic pressure (ITP), provides essential information about chest wall mechanics and its effects on the respiratory system and lung mechanics. The positioning of an esophageal catheter is required to measure the esophageal pressure (Peso), which is clinically used as a surrogate for ITP or pleural pressure (Ppl), and calculates the transpulmonary pressure. The benefits of such a ventilation approach are avoiding excessive lung stress and individualizing the positive end-expiratory pressure (PEEP) setting. The aim is to prevent over-distention of alveoli and the cyclic recruitment/derecruitment or shear stress of lung parenchyma, mechanisms associated with ventilator-induced lung injury (VILI). Knowledge of the real lung distending pressure, i.e. the transpulmonary pressure, has shown to be useful in both controlled and assisted mechanical ventilation. In the latter ventilator modes, Peso measurement allows one to assess a patient's respiratory effort, patient-ventilator asynchrony, intrinsic PEEP and the calculation of work of breathing. Conditions that have an impact on Peso, such as abdominal hypertension, will also be discussed briefly.

  9. Transpulmonary pressure monitoring during mechanical ventilation: a bench-to-bedside review.

    PubMed

    Mietto, Cristina; Malbrain, Manu L N G; Chiumello, Davide

    2015-01-01

    Different ventilation strategies have been suggested in the past in patients with acute respiratory distress syndrome (ARDS). Airway pressure monitoring alone is inadequate to assure optimal ventilatory support in ARDS patients. The assessment of transpulmonary pressure (PTP) can help clinicians to tailor mechanical ventilation to the individual patient needs. Transpulmonary pressure monitoring, defined as airway pressure (Paw) minus intrathoracic pressure (ITP), provides essential information about chest wall mechanics and its effects on the respiratory system and lung mechanics. The positioning of an esophageal catheter is required to measure the esophageal pressure (Peso), which is clinically used as a surrogate for ITP or pleural pressure (Ppl), and calculates the transpulmonary pressure. The benefits of such a ventilation approach are avoiding excessive lung stress and individualizing the positive end-expiratory pressure (PEEP) setting. The aim is to prevent over-distention of alveoli and the cyclic recruitment/derecruitment or shear stress of lung parenchyma, mechanisms associated with ventilator-induced lung injury (VILI). Knowledge of the real lung distending pressure, i.e. the transpulmonary pressure, has shown to be useful in both controlled and assisted mechanical ventilation. In the latter ventilator modes, Peso measurement allows one to assess a patient's respiratory effort, patient-ventilator asynchrony, intrinsic PEEP and the calculation of work of breathing. Conditions that have an impact on Peso, such as abdominal hypertension, will also be discussed briefly. PMID:26575165

  10. Approaches to manual ventilation.

    PubMed

    Davies, John D; Costa, Brian K; Asciutto, Anthony J

    2014-06-01

    Manual ventilation is a basic skill that involves airway assessment, maneuvers to open the airway, and application of simple and complex airway support devices and effective positive-pressure ventilation using a bag and mask. An important part of manual ventilation is recognizing its success and when it is difficult or impossible and a higher level of support is necessary to sustain life. Careful airway assessment will help clinicians identify what and when the next step needs to be taken. Often simple airway maneuvers such as the head tilt/chin lift and jaw thrust can achieve a patent airway. Appropriate use of airway adjuncts can further aid the clinician in situations in which airway maneuvers may not be sufficient. Bag-mask ventilation (BMV) plays a vital role in effective manual ventilation, improving both oxygenation and ventilation as well as buying time while preparations are made for endotracheal intubation. There are, however, situations in which BMV may be difficult or impossible. Anticipation and early recognition of these situations allows clinicians to quickly make adjustments to the method of BMV or to employ a more advanced intervention to avoid delays in establishing adequate oxygenation and ventilation.

  11. Developments in longwall ventilation

    SciTech Connect

    Brune, J.F.; Aman, J.P.; Kotch, M.

    1999-07-01

    Rapid development in longwall mining technology has brought significant changes in panel layout and geometry. These changes require adaptations in the ventilation system to provide sufficient air quantities in longwall face and bleeder areas. At CONSOL, various longwall bleeder systems in the Pittsburgh No. 8 Seam have been studied with detailed ventilation surveys. Computer model network simulations were conducted from these surveys to study the effects of different bleeder configurations and ventilation adjustments. This paper examines the relationships between the longwall face air quantity and the convergence in the tailgate-to-bleeder entries, number of development entries, bleeder fan pressure and the tailgate ventilation scheme. It shows that, using conventional ventilation patterns, the face air quantity may be limited if the gob caves tightly. In such cases, modification of the ventilation pattern to an internal bleeder system, combined with appropriate tailgate ventilation and higher bleeder fan pressure may be required. Experience in CONSOL's operations has proven this method successful especially in mines that changed from four-entry to three-entry longwall development.

  12. Pressure control to accommodate patient breathing efforts during volume ventilation.

    PubMed

    Stawitcke, F A; Ream, A K; Piziali, R L

    1987-04-01

    Intermittent positive-pressure ventilation is used to support patients whose unassisted breathing is inadequate. Mechanical ventilators deliver pressurized gas to the patient's lungs by using a pattern of volume and timing that is preset by the clinician. A weakness of existing control methods is their emphasis on maintaining adequate gas exchange while poorly accommodating the patient's efforts to reassume control of the delivery pattern. A method is proposed to control airway pressure within a breath by making it respond to measurements of volume. This method using pressure as a function of volume, or P(V) method, permits the patient to have transient control over flow rate and delivered volume. In addition, an adaptive controller is included that modifies the applied pressure during subsequent breaths; it assures an average flow rate and delivered volume at the levels prescribed by the clinician, when sustained changes occur in airway resistance, lung-thorax compliance, or breathing efforts. Analyses and computer simulations suggest that the P(V) method will be better than conventional volume ventilation in accommodating, within a breath, transient breathing efforts without long-term degradation of the prescribed delivery pattern. The P(V) method can restore the delivery pattern, using the adaptive controller, within a few breaths after changes occur in the patient's lung mechanics. We conclude that the P(V) method is feasible, that it may represent an improved method of patient ventilation, particularly during fighting or weaning from the ventilator, and that it warrants further investigation.

  13. Ventilating Air-Conditioner

    NASA Technical Reports Server (NTRS)

    Dinh, Khanh

    1994-01-01

    Air-conditioner provides ventilation designed to be used alone or incorporated into cooling or heating system operates efficiently only by recirculating stale air within building. Energy needed to operate overall ventilating cooling or heating system slightly greater than operating nonventilating cooling or heating system. Helps to preserve energy efficiency while satisfying need for increased forced ventilation to prevent accumulation of undesired gases like radon and formaldehyde. Provides fresh treated air to variety of confined spaces: hospital surgeries, laboratories, clean rooms, and printing shops and other places where solvents used. In mobile homes and portable classrooms, eliminates irritant chemicals exuded by carpets, panels, and other materials, ensuring healthy indoor environment for occupants.

  14. [Ventilation strategies in the child with severe hypoxemic respiratory failure].

    PubMed

    Donoso F, Alejandro; Arriagada S, Daniela; Díaz R, Franco; Cruces R, Pablo

    2015-01-01

    In this review, we assemble the fundamental concepts of the use of mechanical ventilation (MV) in children with acute respiratory failure (ARDS) and refractory hypoxemia. We also discusses topics of protective ventilation and recruitment potential, and specifically examine the options of ventilation and/or maneuvers designed to optimize the non-aerated lung tissue: alveolar recruitment maneuvers, positive end-expiratory pressure (PEEP) titulation, high frequency oscillatory ventilation (HFOV), airway pressure release ventilation (APRV), aimed at correcting the mismatch ventilation/perfusion (V/Q): use of prone position. The only pharmacological intervention analyzed is the use of neuromuscular blockers. In clinical practice, the protective MV concept involves using an individual adjustment of the PEEP and volume tidal (V(T)). Use of recruitment maneuvers and PEEP downward titration can improve lung function in patients with ARDS and severe hypoxemia. We must keep in mind HFOV instauration as early as possible in response to failure of MV. The use of early and prolonged prone can improve gas exchange in hopes of a better control of what caused the use of MV. PMID:25739487

  15. Sleep in patients with restrictive lung disease.

    PubMed

    Won, Christine H J; Kryger, Meir

    2014-09-01

    Restrictive lung disease leads to ventilatory defects and diffusion impairments. These changes may contribute to abnormal nocturnal pathophysiology, including sleep architecture disruption and impaired ventilation and oxygenation. Patients with restrictive lung disease may suffer significant daytime fatigue and dysfunction. Hypercarbia and hypoxemia during sleep may impact progression of lung disease and related symptoms. Little is known about the impact of treatment of sleep disruption on sleep quality and overall prognosis in restrictive lung disease. This review discusses the pathophysiology of sleep and comorbid sleep disorders in restrictive lung diseases including interstitial lung disease, neuromuscular disease, and obesity hypoventilation syndrome.

  16. Glutamine Attenuates Acute Lung Injury Caused by Acid Aspiration

    PubMed Central

    Lai, Chih-Cheng; Liu, Wei-Lun; Chen, Chin-Ming

    2014-01-01

    Inadequate ventilator settings may cause overwhelming inflammatory responses associated with ventilator-induced lung injury (VILI) in patients with acute respiratory distress syndrome (ARDS). Here, we examined potential benefits of glutamine (GLN) on a two-hit model for VILI after acid aspiration-induced lung injury in rats. Rats were intratracheally challenged with hydrochloric acid as a first hit to induce lung inflammation, then randomly received intravenous GLN or lactated Ringer’s solution (vehicle control) thirty min before different ventilator strategies. Rats were then randomized to receive mechanical ventilation as a second hit with a high tidal volume (TV) of 15 mL/kg and zero positive end-expiratory pressure (PEEP) or a low TV of 6 mL/kg with PEEP of 5 cm H2O. We evaluated lung oxygenation, inflammation, mechanics, and histology. After ventilator use for 4 h, high TV resulted in greater lung injury physiologic and biologic indices. Compared with vehicle treated rats, GLN administration attenuated lung injury, with improved oxygenation and static compliance, and decreased respiratory elastance, lung edema, extended lung destruction (lung injury scores and lung histology), neutrophil recruitment in the lung, and cytokine production. Thus, GLN administration improved the physiologic and biologic profiles of this experimental model of VILI based on the two-hit theory. PMID:25100435

  17. Pancreas transplants: Evaluation using perfusion scintigraphy

    SciTech Connect

    Kuni, C.C.; du Cret, R.P.; Boudreau, R.J.

    1989-07-01

    To determine the value of scintigraphic perfusion studies in evaluating pancreas transplant patients, we reviewed 56 of these studies in 22 patients who had 27 transplants. Seventeen patients underwent two or more studies. The perfusion studies were performed with 20 mCi (740 MBq) of 99mTc-DTPA injected as a bolus followed by eight to 16 serial 2-sec images and a 500,000-count immediate static image. Images were evaluated for (1) the time and intensity of pancreatic peak radioactivity relative to the time and intensity of the iliac arterial peak; (2) relative pancreatic to iliac arterial intensity on the static image; and (3) size, homogeneity, and definition of the pancreas. Clinical diagnoses at the time of scintigraphy of normal function (n = 36), rejection (n = 13), pancreatitis (n = 6), or arterial thrombosis (n = 1) were based on insulin requirement, urine amylase, serum glucose, serum amylase, response to therapy, cultures, CT, MR, sonography, scintigraphy with 67Ga or 111In-WBCs, percutaneous drainage results, angiography, surgery, and pathologic examination of resected transplants. Three 99mTc-DTPA perfusion studies showed no pancreatic perfusion, four showed decreasing perfusion on serial studies, and five showed progressive loss of definition of the pancreas on serial studies. Of the three patients with no detectable perfusion, one had a normally functioning transplant, one had arterial thrombosis with transplant infarction, and one had severe rejection with minimal function. Decreasing perfusion was associated with rejection in three patients and pancreatitis in one. Decreasing definition was seen in four patients with rejection and one with pancreatitis. We conclude that perfusion scintigraphy is useful, primarily when performed serially, although nonspecific for evaluating pancreas transplants.

  18. The effects of closed endotracheal suction on ventilation during conventional and high-frequency oscillatory ventilation.

    PubMed

    Kiraly, Nicholas J; Tingay, David G; Mills, John F; Morley, Colin J; Dargaville, Peter A; Copnell, Beverley

    2009-10-01

    In newborn infants, closed endotracheal tube (ETT) suction may reduce associated adverse effects, but it is not clear whether ventilation is maintained during the procedure. We aimed to determine the effect of ETT size, catheter size, and suction pressure on ventilation parameters measured distal to the ETT. Suction was performed on a test lung, ventilated with conventional (CMV) and high-frequency oscillatory ventilation (HFOV) using ETT sizes 2.5-4.0 mm, catheter sizes 5-8 French gauge (Fr), and suction pressures 80-200 mm Hg. Tracheal and circuit peak inspiratory pressure, positive end-expiratory pressure, and tracheal tidal volume (VT) were recorded for each suction episode. During both CMV and HFOV, tracheal pressures and VT were considerably reduced by suctioning; this reduction was dependent on the combination of ETT, catheter, and suction pressure. Loss of VT, inflation pressure (CMV), and pressure amplitude (HFOV) occurred primarily with insertion of the catheter, and loss of end-expiratory pressure (CMV) and mean tracheal pressure (HFOV) occurred with the application of suction. Circuit pressures were reduced to lesser degree. We conclude that airway pressures and VT are not maintained during closed endotracheal suction with either CMV or HFOV, and choice of equipment and settings will affect the degree of interruption to ventilation.

  19. Prediction of postoperative pulmonary function following thoracic operations. Value of ventilation-perfusion scanning

    SciTech Connect

    Bria, W.F.; Kanarek, D.J.; Kazemi, H.

    1983-08-01

    Surgical resection of lung cancer is frequently required in patients with severely impaired lung function resulting from chronic obstructive pulmonary disease. Twenty patients with obstructive lung disease and cancer (mean preoperative forced expiratory volume in 1 second (FEV1) . 1.73 L) were studied preoperatively and postoperatively by spirometry and radionuclide perfusion, single-breath ventilation, and washout techniques to test the ability of these methods to predict preoperatively the partial loss of lung function by the resection. Postoperative FEV1 and forced vital capacity (FVC) were accurately predicted by the formula: postoperative FEV1 (or FVC) . preoperative FEV1 X percent function of regions of lung not to be resected (r . 0.88 and 0.95, respectively). Ventilation and perfusion scans are equally effective in prediction. Washout data add to the sophistication of the method by permitting the qualitative evaluation of ventilation during tidal breathing. Criteria for patients requiring the study are suggested.

  20. Endocrine scintigraphy with hybrid SPECT/CT.

    PubMed

    Wong, Ka Kit; Fig, Lorraine M; Youssef, Ehab; Ferretti, Alice; Rubello, Domenico; Gross, Milton D

    2014-10-01

    Nuclear medicine imaging of endocrine disorders takes advantage of unique cellular properties of endocrine organs and tissues that can be depicted by targeted radiopharmaceuticals. Detailed functional maps of biodistributions of radiopharmaceutical uptake can be displayed in three-dimensional tomographic formats, using single photon emission computed tomography (CT) that can now be directly combined with simultaneously acquired cross-sectional anatomic maps derived from CT. The integration of function depicted by scintigraphy and anatomy with CT has synergistically improved the efficacy of nuclear medicine imaging across a broad spectrum of clinical applications, which include some of the oldest imaging studies of endocrine dysfunction.

  1. Why We Ventilate

    SciTech Connect

    Logue, Jennifer M.; Sherman, Max H.; Price, Phil N.; Singer, Brett C.

    2011-09-01

    It is widely accepted that ventilation is critical for providing good indoor air quality (IAQ) in homes. However, the definition of"good" IAQ, and the most effective, energy efficient methods for delivering it are still matters of research and debate. This paper presents the results of work done at the Lawrence Berkeley National Lab to identify the air pollutants that drive the need for ventilation as part of a larger effort to develop a health-based ventilation standard. First, we present results of a hazard analysis that identified the pollutants that most commonly reach concentrations in homes that exceed health-based standards or guidelines for chronic or acute exposures. Second, we present results of an impact assessment that identified the air pollutants that cause the most harm to the U.S. population from chronic inhalation in residences. Lastly, we describe the implications of our findings for developing effective ventilation standards.

  2. Scintigraphic perfusion patterns in patients with diffuse lung disease

    SciTech Connect

    Newman, G.E.; Sullivan, D.C.; Gottschalk, A.; Putman, C.E.

    1982-04-01

    Perfusion scintigrams of 55 patients with radiographic evidence of diffuse lung disease were reviewed. Thirty-nine had acute and/or chronic changes caused by congestive heart failure, and 16 had diffuse reticulonodular disease. A normal or near-normal perfusion pattern was seen in 40/55 (73%), and this finding was equally common in the two groups. The authors conclude that perfusion scintigraphy is useful in excluding pulmonary embolism in patients with radiographic evidence of diffuse, symmetrical lung disease.

  3. Conventional mechanical ventilation

    PubMed Central

    Tobias, Joseph D.

    2010-01-01

    The provision of mechanical ventilation for the support of infants and children with respiratory failure or insufficiency is one of the most common techniques that are performed in the Pediatric Intensive Care Unit (PICU). Despite its widespread application in the PICUs of the 21st century, before the 1930s, respiratory failure was uniformly fatal due to the lack of equipment and techniques for airway management and ventilatory support. The operating rooms of the 1950s and 1960s provided the arena for the development of the manual skills and the refinement of the equipment needed for airway management, which subsequently led to the more widespread use of endotracheal intubation thereby ushering in the era of positive pressure ventilation. Although there seems to be an ever increasing complexity in the techniques of mechanical ventilation, its successful use in the PICU should be guided by the basic principles of gas exchange and the physiology of respiratory function. With an understanding of these key concepts and the use of basic concepts of mechanical ventilation, this technique can be successfully applied in both the PICU and the operating room. This article reviews the basic physiology of gas exchange, principles of pulmonary physiology, and the concepts of mechanical ventilation to provide an overview of the knowledge required for the provision of conventional mechanical ventilation in various clinical arenas. PMID:20927268

  4. SU-C-BRA-06: Developing Clinical and Quantitative Guidelines for a 4DCT-Ventilation Functional Avoidance Clinical Trial

    SciTech Connect

    Vinogradskiy, Y; Waxweiler, T; Diot, Q; Kavanagh, B; Schubert, L; Miften, M; Castillo, R; Guerrero, T; Castillo, E

    2015-06-15

    Purpose: 4DCT-ventilation is an exciting new imaging modality that uses 4DCTs to calculate lung ventilation. Because 4DCTs are acquired as part of routine care, calculating 4DCT-ventilation allows for lung function evaluation without additional cost or inconvenience to the patient. Development of a clinical trial is underway at our institution to use 4DCT-ventilation for thoracic functional avoidance with the idea that preferential sparing of functional lung regions can decrease pulmonary toxicity. The purpose of our work was to develop the practical aspects of a 4DCT-ventilation functional avoidance clinical trial including: 1.assessing patient eligibility 2.developing trial inclusion criteria and 3.developing treatment planning and dose-function evaluation strategies. Methods: 96 stage III lung cancer patients from 2 institutions were retrospectively reviewed. 4DCT-ventilation maps were calculated using the patient’s 4DCTs, deformable image registrations, and a density-change-based algorithm. To assess patient eligibility and develop trial inclusion criteria we used an observer-based binary end point noting the presence or absence of a ventilation defect and developed an algorithm based on the percent ventilation in each lung third. Functional avoidance planning integrating 4DCT-ventilation was performed using rapid-arc and compared to the patient’s clinically used plan. Results: Investigator-determined clinical ventilation defects were present in 69% of patients. Our regional/lung-thirds ventilation algorithm identified that 59% of patients have lung functional profiles suitable for functional avoidance. Compared to the clinical plan, functional avoidance planning was able to reduce the mean dose to functional lung by 2 Gy while delivering comparable target coverage and cord/heart doses. Conclusions: 4DCT-ventilation functional avoidance clinical trials have great potential to reduce toxicity, and our data suggest that 59% of lung cancer patients have lung

  5. Do all mechanically ventilated pediatric patients require continuous capnography?

    PubMed

    Hamel, Donna S; Cheifetz, Ira M

    2006-09-01

    With most patients in modern ICUs requiring mechanical ventilation, any technology that may lead to more optimal ventilatory strategies would be invaluable in the management of critically ill patients. The focus of most ventilator strategies is protecting the lung from the deleterious effects of mechanical ventilation. Every effort is made to minimize the duration of mechanical ventilation while optimizing the potential for successful extubation. A concise organized plan based on objective criteria that is adjusted to meet changes in patient status is clearly recommended. Continuous capnographic monitoring provides clinicians with clear, precise, objective data that may prove beneficial in the design and implementation of mechanical ventilatory strategies. There are no clear-cut methods for achieving the optimal ventilator strategy for a specific patient. Although guidelines and management theories exist throughout the medical literature, in practice, they often merely serve as loose guidelines. The dynamic properties of an acutely ill patient make the management of mechanical ventilation an ongoing process requiring clinical assessment and planning by multidisciplinary members of the patient care team. Comprehensive evaluation of ventilatory management strategies and patient responses must be made by a collaborative effort of physicians, respiratory care practitioners, and nurses. An objective, consistent approach to the overall management is essential. Although still controversial, it is the authors' opinion that volumetric capnograph provides the data necessary to establish adequate gas delivery, optimal PEEP, and effective ventilation with the least amount of mechanical assistance, regardless of clinician or institutional preferences. PMID:16952808

  6. Idiopathic pulmonary fibrosis. A rare cause of scintigraphic ventilation-perfusion mismatch

    SciTech Connect

    Pochis, W.T.; Krasnow, A.Z.; Collier, B.D.; Mewissen, M.W.; Almagro, U.A.; Hellman, R.S.; Isitman, A.T. )

    1990-05-01

    A case of idiopathic pulmonary fibrosis with multiple areas of mismatch on ventilation-perfusion lung imaging in the absence of pulmonary embolism is presented. Idiopathic pulmonary fibrosis is one of the few nonembolic diseases producing a pulmonary ventilation-perfusion mismatch. In this condition, chest radiographs may not detect the full extent of disease, and xenon-133 ventilation imaging may be relatively insensitive to morbid changes in small airways. Thus, when examining patients with idiopathic pulmonary fibrosis, one should be aware that abnormal perfusion imaging patterns without matching ventilation abnormalities are not always due to embolism. In this setting, contrast pulmonary angiography is often needed for accurate differential diagnosis.

  7. Evaluation of Fractional Regional Ventilation Using 4D-CT and Effects of Breathing Maneuvers on Ventilation

    SciTech Connect

    Mistry, Nilesh N.; Diwanji, Tejan; Shi, Xiutao; Pokharel, Sabin; Feigenberg, Steven; Scharf, Steven M.; D'Souza, Warren D.

    2013-11-15

    Purpose: Current implementations of methods based on Hounsfield units to evaluate regional lung ventilation do not directly incorporate tissue-based mass changes that occur over the respiratory cycle. To overcome this, we developed a 4-dimensional computed tomography (4D-CT)-based technique to evaluate fractional regional ventilation (FRV) that uses an individualized ratio of tidal volume to end-expiratory lung volume for each voxel. We further evaluated the effect of different breathing maneuvers on regional ventilation. The results from this work will help elucidate the relationship between global and regional lung function. Methods and Materials: Eight patients underwent 3 sets of 4D-CT scans during 1 session using free-breathing, audiovisual guidance, and active breathing control. FRV was estimated using a density-based algorithm with mass correction. Internal validation between global and regional ventilation was performed by use of the imaging data collected during the use of active breathing control. The impact of breathing maneuvers on FRV was evaluated comparing the tidal volume from 3 breathing methods. Results: Internal validation through comparison between the global and regional changes in ventilation revealed a strong linear correlation (slope of 1.01, R{sup 2} of 0.97) between the measured global lung volume and the regional lung volume calculated by use of the “mass corrected” FRV. A linear relationship was established between the tidal volume measured with the automated breathing control system and FRV based on 4D-CT imaging. Consistently larger breathing volumes were observed when coached breathing techniques were used. Conclusions: The technique presented improves density-based evaluation of lung ventilation and establishes a link between global and regional lung ventilation volumes. Furthermore, the results obtained are comparable with those of other techniques of functional evaluation such as spirometry and hyperpolarized-gas magnetic

  8. 14 CFR 25.831 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.831 Ventilation... probable failures or malfunctioning of the ventilating, heating, pressurization, or other systems...

  9. 14 CFR 25.831 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.831 Ventilation... probable failures or malfunctioning of the ventilating, heating, pressurization, or other systems...

  10. 14 CFR 25.831 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.831 Ventilation... probable failures or malfunctioning of the ventilating, heating, pressurization, or other systems...

  11. 14 CFR 25.831 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.831 Ventilation... probable failures or malfunctioning of the ventilating, heating, pressurization, or other systems...

  12. Unusual False Positive Radioiodine Uptake on (131)I Whole Body Scintigraphy in Three Unrelated Organs with Different Pathologies in Patients of Differentiated Thyroid Carcinoma: A Case Series.

    PubMed

    Ranade, Rohit; Pawar, Shwetal; Mahajan, Abhishek; Basu, Sandip

    2016-01-01

    Three cases with unusual false positive radioiodine uptake in three different organs and pathologies (infective old fibrotic lesion in the lung, simple liver cyst, and benign breast lesion) on iodine-131 ((131)I) whole body scintigraphy. Clinicoradiological correlation was undertaken in all three cases and the pathologies were ascertained. In all the three cases, single-photon emission computerized tomography-computed tomography (SPECT-CT) and ancillary imaging modalities were employed and were helpful in arriving at the final diagnosis.

  13. Unusual False Positive Radioiodine Uptake on 131I Whole Body Scintigraphy in Three Unrelated Organs with Different Pathologies in Patients of Differentiated Thyroid Carcinoma: A Case Series

    PubMed Central

    Ranade, Rohit; Pawar, Shwetal; Mahajan, Abhishek; Basu, Sandip

    2016-01-01

    Three cases with unusual false positive radioiodine uptake in three different organs and pathologies (infective old fibrotic lesion in the lung, simple liver cyst, and benign breast lesion) on iodine-131 (131I) whole body scintigraphy. Clinicoradiological correlation was undertaken in all three cases and the pathologies were ascertained. In all the three cases, single-photon emission computerized tomography-computed tomography (SPECT-CT) and ancillary imaging modalities were employed and were helpful in arriving at the final diagnosis. PMID:27134566

  14. [Intraoperative protective ventilation reduces postoperative pulmonary complications - PRO].

    PubMed

    Güldner, Andreas; Gama de Abreu, Marcelo

    2015-09-01

    Postoperative pulmonary complications add to higher mortality and morbidity. This risk could be lowered with intraoperative protective ventilation, especially with low tidal volumes. The application of PEEP and the use of recruitment maneuvers can enhance the lung function during surgery, but can also cause haemodynamic instability. In patients with open abdominal surgery and no lung damage or obesity, PEEP and recruitment maneuvers have no protective effect against postoperative pulmonary complications. It is still unclear, wether the use of intraoperative PEEP in other patient groups and during different surgery procedures is relevant for lung protection.

  15. Hyperoxic Acute Lung Injury

    PubMed Central

    Kallet, Richard H; Matthay, Michael A

    2013-01-01

    Prolonged breathing of very high FIO2 (FIO2 ≥ 0.9) uniformly causes severe hyperoxic acute lung injury (HALI) and, without a reduction of FIO2, is usually fatal. The severity of HALI is directly proportional to PO2 (particularly above 450 mm Hg, or an FIO2 of 0.6) and exposure duration. Hyperoxia produces extraordinary amounts of reactive O2 species that overwhelms natural antioxidant defenses and destroys cellular structures through several pathways. Genetic predisposition has been shown to play an important role in HALI among animals, and some genetics-based epidemiologic research suggests that this may be true for humans as well. Clinically, the risk of HALI likely occurs when FIO2exceeds 0.7, and may become problematic when FIO2 exceeds 0.8 for an extended period of time. Both high-stretch mechanical ventilation and hyperoxia potentiate lung injury and may promote pulmonary infection. During the 1960s, confusion regarding the incidence and relevance of HALI largely reflected such issues as the primitive control of FIO2, the absence of PEEP, and the fact that at the time both ALI and ventilator-induced lung injury were unknown. The advent of PEEP and precise control over FIO2, as well as lung-protective ventilation, and other adjunctive therapies for severe hypoxemia, has greatly reduced the risk of HALI for the vast majority of patients requiring mechanical ventilation in the 21st century. However, a subset of patients with very severe ARDS requiring hyperoxic therapy is at substantial risk for developing HALI, therefore justifying the use of such adjunctive therapies. PMID:23271823

  16. Surfactant phosphatidylcholine metabolism and surfactant function in preterm, ventilated lambs

    SciTech Connect

    Jobe, A.H.; Ikegami, M.; Seidner, S.R.; Pettenazzo, A.; Ruffini, L.

    1989-02-01

    Preterm lambs were delivered at 138 days gestational age and ventilated for periods up to 24 h in order to study surfactant metabolism and surfactant function. The surfactant-saturated phosphatidylcholine pool in the alveolar wash was 13 +/- 4 mumol/kg and did not change from 10 min to 24 h after birth. Trace amounts of labeled natural sheep surfactant were mixed with fetal lung fluid at birth. By 24 h, 80% of the label had become lung-tissue-associated, yet there was no loss of label from phosphatidylcholine in the lungs when calculated as the sum of the lung tissue plus alveolar wash. De novo synthesized phosphatidylcholine was labeled with choline given by intravascular injection at 1 h of age. Labeled phosphatidylcholine accumulated in the lung tissue linearly to 24 h, and the labeled phosphatidylcholine moved through lamellar body to alveolar pools. The turnover time for alveolar phosphatidylcholine was estimated to be about 13 h, indicating an active metabolic pool. A less surface-active surfactant fraction recovered as a supernatant after centrifugation of the alveolar washes at 40,000 x g increased from birth to 10 min of ventilation, but no subsequent changes in the distribution of surfactant phosphatidylcholine in surfactant fractions occurred. The results were consistent with recycling pathway(s) that maintained surface-active surfactant pools in preterm ventilated lambs.

  17. Comparison of gamma scintigraphy and a pharmacokinetic technique for assessing pulmonary deposition of terbutaline sulphate delivered by pressurized metered dose inhaler.

    PubMed

    Newman, S; Steed, K; Hooper, G; Källén, A; Borgström, L

    1995-02-01

    A comparison has been made of pulmonary deposition of terbutaline sulphate from a pressurized metered dose inhaler (pMDI), measured in 8 healthy male subjects by gamma scintigraphy and by a pharmacokinetic (charcoal-block) method, involving drug recovery in urine. Measurements were carried out with a pMDI at slow (27 l/min) and fast (151 l/min) inhaled flows and with Nebuhaler large volume spacer device (average inhaled flow 17 l/min). Overall, the two methods did not differ significantly in their estimates of whole lung deposition, although values obtained by gamma scintigraphy exceeded those from the charcoal-block method for the pMDI with fast inhalation. The regional distribution of drug within the lungs and deposition in the oropharynx could be assessed by gamma scintigraphy, but not by the charcoal-block method. It is concluded that either method may be used to assess whole lung deposition of terbutaline sulphate from pMDIs, both with and without a spacer, although each method has its own inherent advantages and disadvantages. PMID:7784338

  18. Portosystemic shunting in portal hypertension: evaluation with portal scintigraphy with transrectally administered I-123 IMP

    SciTech Connect

    Kashiwagi, T.; Azuma, M.; Ikawa, T.; Takehara, T.; Matsuda, H.; Yoshioka, H.; Mitsutani, N.; Koizumi, T.; Kimura, K.

    1988-10-01

    Portosystemic shunting was evaluated with rectal administration of iodine-123 iodoamphetamine (IMP) in seven patients without liver disease and 53 patients with liver cirrhosis. IMP (2-3 mCi (74-111 MBq)) was administered to the rectum through a catheter. Images of the chest and abdomen were obtained for up to 60 minutes with a scintillation camera interfaced with a computer. In all patients, images of the liver and/or lungs were observed within 5-10 minutes and became clear with time. In patients without liver disease, only liver images could be obtained, whereas the lung was visualized with or without the liver in all patients with liver cirrhosis. The portosystemic shunt index was calculated by dividing counts of lungs by counts of liver and lung. These values were significantly higher in liver cirrhosis, especially in the decompensated stage. Transrectal portal scintigraphy with IMP appears to be a useful method for noninvasive and quantitative evaluation of portosystemic shunting in portal hypertension.

  19. Ventilation technologies scoping study

    SciTech Connect

    Walker, Iain S.; Sherman, Max H.

    2003-09-30

    This document presents the findings of a scoping study commissioned by the Public Interest Energy Research (PIER) program of the California Energy Commission to determine what research is necessary to develop new residential ventilation requirements for California. This study is one of three companion efforts needed to complete the job of determining the needs of California, determining residential ventilation requirements, and determining appropriate ventilation technologies to meet these needs and requirements in an energy efficient manner. Rather than providing research results, this scoping study identifies important research questions along with the level of effort necessary to address these questions and the costs, risks, and benefits of pursuing alternative research questions. In approaching these questions and level of effort, feasibility and timing were important considerations. The Commission has specified Summer 2005 as the latest date for completing this research in time to update the 2008 version of California's Energy Code (Title 24).

  20. A bench study of intensive-care-unit ventilators: new versus old and turbine-based versus compressed gas-based ventilators

    PubMed Central

    Thille, Arnaud W.; Lyazidi, Aissam; Richard, Jean-Christophe M.; Galia, Fabrice; Brochard, Laurent

    2009-01-01

    Objective To compare 13 commercially available, new-generation, intensive-care-unit (ICU) ventilators regarding trigger function, pressurization capacity during pressure-support ventilation (PSV), accuracy of pressure measurements and expiratory resistance. Design and Setting Bench study at a research laboratory in a university hospital. Material Four turbine-based ventilators and nine conventional servo-valve compressed-gas ventilators were tested using a two-compartment lung model. Results Three levels of effort were simulated. Each ventilator was evaluated at four PSV levels (5, 10, 15, and 20 cm H2O), with and without positive end-expiratory pressure (5 cm H2O, Trigger function was assessed as the time from effort onset to detectable pressurization. Pressurization capacity was evaluated using the airway pressure-time product computed as the net area under the pressure-time curve over the first 0.3 s after inspiratory effort onset. Expiratory resistance was evaluated by measuring trapped volume in controlled ventilation. Significant differences were found across the ventilators, with a range of triggering-delay from 42 ms to 88 ms for all conditions averaged (P<.001). Under difficult conditions, the triggering delay was longer than 100 ms and the pressurization was poor with five ventilators at PSV5 and three at PSV10, suggesting an inability to unload patient’s effort. On average, turbine-based ventilators performed better than conventional ventilators, which showed no improvement compared to a 2000 bench comparison. Conclusion Technical performances of trigger function, pressurization capacity and expiratory resistance vary considerably across new-generation ICU ventilators. ICU ventilators seem to have reached a technical ceiling in recent years, and some ventilators still perform inadequately. PMID:19352622

  1. Electrical impedance tomography for assessing ventilation/perfusion mismatch for pulmonary embolism detection without interruptions in respiration.

    PubMed

    Nguyen, Doan Trang; Thiagalingam, Aravinda; Bhaskaran, Abhishek; Barry, Michael A; Pouliopoulos, Jim; Jin, Craig; McEwan, Alistair L

    2014-01-01

    Recent studies have shown high correlation between pulmonary perfusion mapping with impedance contrast enhanced Electrical Impedance Tomography (EIT) and standard perfusion imaging methods such as Computed Tomography (CT) and Single Photon Emission Computerized Tomography (SPECT). EIT has many advantages over standard imaging methods as it is highly portable and non-invasive. Contrast enhanced EIT uses hypertonic saline bolus instead of nephrotoxic contrast medium that are utilized by CT and nuclear Ventilation/Perfusion (V/Q) scans. However, current implementation of contrast enhanced EIT requires induction of an apnea period for perfusion measurement, rendering it disadvantageous compared with current gold standard imaging modalities. In the present paper, we propose the use of a wavelet denoising algorithm to separate perfusion signal from ventilation signal such that no interruption in patient's ventilation would be required. Furthermore, right lung to left lung perfusion ratio and ventilation ratio are proposed to assess the mismatch between ventilation and perfusion for detection of Pulmonary Embolism (PE). The proposed methodology was validated on an ovine model (n=3, 83.7±7.7 kg) with artificially induced PE in the right lung. The results showed a difference in right lung to left lung perfusion ratio between baseline and diseased states in all cases with all paired t-tests between baseline and PE yielding p <; 0.01, while the right lung to left lung ventilation ratio remained unchanged in two out of three experiments. Statistics were pooled from multiple repetitions of measurements per experiment.

  2. Meeting Residential Ventilation Standards Through Dynamic Control of Ventilation Systems

    SciTech Connect

    Sherman, Max H.; Walker, Iain S.

    2011-04-01

    Existing ventilation standards, including American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE) Standard 62.2, specify continuous operation of a defined mechanical ventilation system to provide minimum ventilation, with time-based intermittent operation as an option. This requirement ignores several factors and concerns including: other equipment such as household exhaust fans that might incidentally provide ventilation, negative impacts of ventilation when outdoor pollutant levels are high, the importance of minimizing energy use particularly during times of peak electricity demand, and how the energy used to condition air as part of ventilation system operation changes with outdoor conditions. Dynamic control of ventilation systems can provide ventilation equivalent to or better than what is required by standards while minimizing energy costs and can also add value by shifting load during peak times and reducing intake of outdoor air contaminants. This article describes the logic that enables dynamic control of whole-house ventilation systems to meet the intent of ventilation standards and demonstrates the dynamic ventilation system control concept through simulations and field tests of the Residential Integrated Ventilation-Energy Controller (RIVEC).

  3. Detection of deep venous thrombophlebitis by gallium 67 scintigraphy

    SciTech Connect

    Miller, J.H.

    1981-07-01

    Deep venous thrombophlebitis may escape clinical detection. Three cases are reported in which whole-body gallium 67 scintigraphy was used to detect unsuspected deep venous thrombophlebitis related to indwelling catheters in three children who were being evaluated for fevers of unknown origin. Two of these children had septicemia from Candida organisms secondary to these venous lines. Gallium 67 scintigraphy may be useful in the detection of complications of indwelling venous catheters.

  4. Central Fan Integrated Ventilation Systems

    SciTech Connect

    2009-05-12

    This information sheet describes one example of a ventilation system design, a central fan integrated supply (CFIS) system, a mechanical ventilation and pollutant source control to ensure that there is reasonable indoor air quality inside the house.

  5. SU-E-J-178: A Normalization Method Can Remove Discrepancy in Ventilation Function Due to Different Breathing Patterns

    SciTech Connect

    Qu, H; Yu, N; Stephans, K; Xia, P

    2014-06-01

    Purpose: To develop a normalization method to remove discrepancy in ventilation function due to different breathing patterns. Methods: Twenty five early stage non-small cell lung cancer patients were included in this study. For each patient, a ten phase 4D-CT and the voluntarily maximum inhale and exhale CTs were acquired clinically and retrospectively used for this study. For each patient, two ventilation maps were calculated from voxel-to-voxel CT density variations from two phases of the quiet breathing and two phases of the extreme breathing. For the quiet breathing, 0% (inhale) and 50% (exhale) phases from 4D-CT were used. An in-house tool was developed to calculate and display the ventilation maps. To enable normalization, the whole lung of each patient was evenly divided into three parts in the longitude direction at a coronal image with a maximum lung cross section. The ratio of cumulated ventilation from the top one-third region to the middle one-third region of the lung was calculated for each breathing pattern. Pearson's correlation coefficient was calculated on the ratios of the two breathing patterns for the group. Results: For each patient, the ventilation map from the quiet breathing was different from that of the extreme breathing. When the cumulative ventilation was normalized to the middle one-third of the lung region for each patient, the normalized ventilation functions from the two breathing patterns were consistent. For this group of patients, the correlation coefficient of the normalized ventilations for the two breathing patterns was 0.76 (p < 0.01), indicating a strong correlation in the ventilation function measured from the two breathing patterns. Conclusion: For each patient, the ventilation map is dependent of the breathing pattern. Using a regional normalization method, the discrepancy in ventilation function induced by the different breathing patterns thus different tidal volumes can be removed.

  6. Clinical review: Acute respiratory distress syndrome - clinical ventilator management and adjunct therapy

    PubMed Central

    2013-01-01

    Acute respiratory distress syndrome (ARDS) is a potentially devastating form of acute inflammatory lung injury with a high short-term mortality rate and significant long-term consequences among survivors. Supportive care, principally with mechanical ventilation, remains the cornerstone of therapy - although the goals of this support have changed in recent years - from maintaining normal physiological parameters to avoiding ventilator-induced lung injury while providing adequate gas exchange. In this article we discuss the current evidence base for ventilatory support and adjunctive therapies in patients with ARDS. Key components of such a strategy include avoiding lung overdistension by limiting tidal volumes and airway pressures, and the use of positive end-expiratory pressure with or without lung recruitment manoeuvres in patients with severe ARDS. Adjunctive therapies discussed include pharmacologic techniques (for example, vasodilators, diuretics, neuromuscular blockade) and nonpharmacologic techniques (for example, prone position, alternative modes of ventilation). PMID:23672857

  7. Gallium 67 scintigraphy in glomerular disease

    SciTech Connect

    Bakir, A.A.; Lopez-Majano, V.; Levy, P.S.; Rhee, H.L.; Dunea, G.

    1988-12-01

    To evaluate the diagnostic usefulness of gallium 67 scintigraphy in glomerular disease, 45 patients with various glomerulopathies, excluding lupus nephritis and renal vasculitis, were studied. Persistent renal visualization 48 hours after the gallium injection, a positive scintigram, was graded as + (less than), ++ (equal to), and +++ (greater than) the hepatic uptake. Positive scintigrams were seen in ten of 16 cases of focal segmental glomerulosclerosis, six of 11 cases of proliferative glomerulonephritis, and one case of minimal change, and one of two cases of membranous nephropathy; also in three of six cases of sickle glomerulopathy, two cases of diabetic neuropathy, one of two cases of amyloidosis, and one case of mild chronic allograft rejection. The 25 patients with positive scans were younger than the 20 with negative scans (31 +/- 12 v 42 +/- 17 years; P less than 0.01), and exhibited greater proteinuria (8.19 +/- 7.96 v 2.9 +/- 2.3 S/d; P less than 0.01) and lower serum creatinine values (2 +/- 2 v 4.1 +/- 2.8 mg/dL; P less than 0.01). The amount of proteinuria correlated directly with the intensity grade of the gallium image (P less than 0.02), but there was no correlation between the biopsy diagnosis and the outcome of the gallium scan. It was concluded that gallium scintigraphy is not useful in the differential diagnosis of the glomerular diseases under discussion. Younger patients with good renal function and heavy proteinuria are likely to have a positive renal scintigram regardless of the underlying glomerulopathy.

  8. Noninvasive ventilation for acute respiratory distress syndrome: the importance of ventilator settings

    PubMed Central

    Costa, Eduardo L. V.; Nakamura, Maria A. M.; Morais, Caio C. A.

    2016-01-01

    Noninvasive ventilation (NIV) is commonly used to prevent endotracheal intubation in patients with acute respiratory distress syndrome (ARDS). Patients with hypoxemic acute respiratory failure who fail an NIV trial carry a worse prognosis as compared to those who succeed. Additional factors are also knowingly associated with worse outcomes: higher values of ICU severity score, presence of severe sepsis, and lower ratio of arterial oxygen tension to fraction of inspired oxygen. However, it is still unclear whether NIV failure is responsible for the worse prognosis or if it is merely a marker of the underlying disease severity. There is therefore an ongoing debate as to whether and which ARDS patients are good candidates to an NIV trial. In a recent paper published in JAMA, “Effect of Noninvasive Ventilation Delivered by Helmet vs. Face Mask on the Rate of Endotracheal Intubation in Patients with Acute Respiratory Distress Syndrome: A Randomized Clinical Trial”, Patel et al. evaluated ARDS patients submitted to NIV and drew attention to the importance of the NIV interface. We discussed their interesting findings focusing also on the ventilator settings and on the current barriers to lung protective ventilation in ARDS patients during NIV. PMID:27747041

  9. How to Plan Ventilation Systems.

    ERIC Educational Resources Information Center

    Clarke, John H.

    1963-01-01

    Ventilation systems for factory safety demand careful planning. The increased heat loads and new processes of industry have introduced complex ventilation problems in--(1) ventilation supply, (2) duct work design, (3) space requirements, (4) hood face velocities, (5) discharge stacks, and (6) building eddies. This article describes and diagrams…

  10. Clustered ventilation defects and bilinear respiratory reactance in asthma.

    PubMed

    Donovan, Graham M

    2016-10-01

    Imaging studies of asthmatics typically reveal clustered ventilation patterns, rather than homogeneous ventilation; furthermore, the variation of these clusters suggests that the causes are at least partially dynamic, rather than structural. Theoretical studies have indicated dynamic mechanisms by which homogeneous ventilation solutions lose stability and clustered solutions emerge. At the same time, it has been demonstrated experimentally that respiratory reactance characteristically has a bilinear relationship with lung volume, and that changes to this relationship are indicative of various aspects of disease progression and control. Moreover, the transition point in the bilinear reactance relationship is thought to relate to reopening/recruitment of airway units, and thus may be connected to the bifurcation via which clustered ventilation solutions emerge. In order to investigate this possibility we develop a new model, including both airway-airway coupling and airway-parenchymal coupling, which exhibits both clustered ventilation defects and also a bilinear reactance relationship. Studying this model reveals that (1) the reactance breakpoint is not coincident with the bifurcation; (2) numerous changes to underlying behaviour can alter the reactance breakpoint in ways which mimic the experimental data; and (3) the location of ventilation defects can be a combination of both structural and dynamic factors. PMID:27374171

  11. The synchronization of ventilation and locomotion in horses (Equus caballus).

    PubMed

    Young, I S; Alexander, R; Woakes, A J; Butler, P J; Anderson, L

    1992-05-01

    Ciné film and synchronized records of respiratory flow were obtained from Thoroughbred racehorses cantering on a treadmill at speeds of 9 and 11 m s-1. Horses and some other galloping and hopping mammals link their breathing and locomotion, taking exactly one breath per stride. Three theoretical mechanisms by which the movements of locomotion might drive ventilation are considered. (i) Flexion of the lumbosacral joint and the resulting forward sweep of the pelvis pushes the viscera against the diaphragm. However, back flexion lags behind ventilation at 11 m s-1 and could not exclusively drive ventilation at this speed. (ii) Loading of the thorax by the impact of the forelimbs with the ground might force air out of the lungs. If the respiratory system were damped sufficiently to perform as this mechanism requires, the work of driving ventilation would make up approximately 15% of the total work of running. In comparison with other estimates of the work of ventilation this seems improbably high. (iii) The observed phase relationship between displacements of the viscera, caused by the accelerations of the body during running, and respiratory airflow is not consistent with a tuned visceral piston mechanism driving breathing. Thus, it would seem likely that back flexion is likely to contribute towards driving ventilation but loading of the thorax and the visceral piston mechanism do not.

  12. Long-term mechanical ventilation and nutrition.

    PubMed

    Ambrosino, Nicolino; Clini, Enrico

    2004-05-01

    Mechanical ventilation (MV) in chronic situations is commonly used, either delivered invasively or by means of non-invasive interfaces, to control hypoventilation in patients with chest wall, neuromuscular or obstructive lung diseases (either in adulthood or childhood). The global prevalence of ventilator-assisted individuals (VAI) in Europe ranges from 2 to 30 per 100000 population according to different countries. Nutrition is a common problem to face with in patients with chronic respiratory diseases: nonetheless, it is a key component in the long-term management of underweight COPD patients whose muscular disfunction may rapidly turn to peripheral muscle waste. Since long-term mechanical ventilation (LTMV) is usually prescribed in end-stage respiratory diseases with poor nutritional status, nutrition and dietary intake related problems need to be carefully assessed and corrected in these patients. This paper aims to review the most recent innovations in the field of nutritional status and food intake-related problems of VAI (both in adulthood and in childhood).

  13. Laboratory Ventilation and Safety.

    ERIC Educational Resources Information Center

    Steere, Norman V.

    1965-01-01

    In order to meet the needs of both safety and economy, laboratory ventilation systems must effectively remove air-borne toxic and flammable materials and at the same time exhaust a minimum volume of air. Laboratory hoods are the most commonly used means of removing gases, dusts, mists, vapors, and fumed from laboratory operations. To be effective,…

  14. Measure Guideline: Ventilation Cooling

    SciTech Connect

    Springer, D.; Dakin, B.; German, A.

    2012-04-01

    The purpose of this measure guideline on ventilation cooling is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  15. Space station ventilation study

    NASA Technical Reports Server (NTRS)

    Colombo, G. V.; Allen, G. E.

    1972-01-01

    A ventilation system design and selection method which is applicable to any manned vehicle were developed. The method was used to generate design options for the NASA 33-foot diameter space station, all of which meet the ventilation system design requirements. System characteristics such as weight, volume, and power were normalized to dollar costs for each option. Total system costs for the various options ranged from a worst case $8 million to a group of four which were all approximately $2 million. A system design was then chosen from the $2 million group and is presented in detail. A ventilation system layout was designed for the MSFC space station mockup which provided comfortable, efficient ventilation of the mockup. A conditioned air distribution system design for the 14-foot diameter modular space station, using the same techniques, is also presented. The tradeoff study resulted in the selection of a system which costs $1.9 million, as compared to the alternate configuration which would have cost $2.6 million.

  16. The fissure: interlobar collateral ventilation and implications for endoscopic therapy in emphysema

    PubMed Central

    Koster, Theodoor David; Slebos, Dirk-Jan

    2016-01-01

    In patients with severe emphysema, bronchoscopic lung volume reduction using one-way valves is a promising therapeutic option to improve lung function and quality of life. The goal of this treatment is to achieve a complete lobar atelectasis. In a significant proportion of patients, this atelectasis cannot be achieved due to interlobar collateral ventilation. This collateral ventilation is generated through incomplete lobar fissures. Therefore, only patients with complete fissures and no collateral ventilation can be selected for endobronchial therapy with one-way valves. Incomplete fissures are very common and exhibit a great variation in anatomy. The reported prevalence is 17%–85% for the right major fissure, 19%–74% for the left major fissure, and 20%–90% for the minor fissure. There are several methods of measuring or predicting the presence of collateral ventilation, with computed tomography (CT)-fissure analysis and the Chartis measurement being the most important. CT-fissure analysis is an indirect method to measure the completeness of fissures as a surrogate for collateral ventilation. The Chartis system is an endobronchial method to directly measure the presence of collateral ventilation. Both methods have unique value, and the combination of both can accurately predict the treatment response to the bronchoscopic placement of endobronchial valves. This review provides an in-depth view of lung fissure and collateral ventilation to help understand its importance in selecting the appropriate patients for new emphysema treatments and thus avoid useless treatment in unsuitable patients. PMID:27110109

  17. Liquid ventilator for ultrafast hypothermia induction in juvenile lambs: Preliminary results.

    PubMed

    Nadeau, Mathieu; Sage, Michaël; Kohlhauer, Matthias; Robert, Raymond; Vandamne, Jonathan; Mousseau, Julien; Tissier, Renaud; Praud, Jean-Paul; Walti, Hervé; Micheau, Philippe

    2015-08-01

    Total liquid ventilation (TLV) is an emerging mechanical ventilation technique. In this technique, the lungs are filled with liquid perfluorocarbons (PFC) and a liquid ventilator assures ventilation by periodically renewing a volume of oxygenated, CO2 freed and temperature controlled PFC. A huge difference between conventional mechanical ventilation and TLV relates to the fact that PFCs are about 1500 times denser than air. Thus, the PFCs filled lungs turn into an efficient heat exchanger with the circulating blood. One of the most appealing utilization of the lungs as a heat exchanger in TLV is for ultrafast induction of mild therapeutic hypothermia (MTH) for neuroprotection and cardioprotection after ischemia-reperfusion injuries. This study aimed to perform ultrafast MTH induction by TLV in animals up to 25 kg, then perform a fast post-hypothermic rewarming while maintaining proper ventilation. A thermal model of the lamb and liquid ventilator was developed to predict the dynamic and the control strategy to adopt for MTH induction. Two juvenile lambs were instrumented with temperature sensors in the femoral artery, pulmonary artery, oesophagus, right eardrum and rectum. After stabilization in conventional mechanical ventilation, TLV was initiated with ultrafast MTH induction, followed by posthypothermic rewarming. Preliminary results in the two juvenile lambs reveal that the liquid ventilator Inolivent-6.0 can induce MTH by TLV in less than 2.5 min for systemic arterial blood and in less than 10 min for venous return, esophagus and eardrum. Rectal temperature reached MTH in respectively 19.4 and 17.0 min for both lambs. Experimental results were consistent with the model predictions. Moreover, blood gas analysis exhibited that the gas exchange in the lungs was maintained adequately for the entire experiments.

  18. A comparison of proximal and distal high-frequency jet ventilation in an experimental animal model.

    PubMed

    Bandy, K P; Donn, S M; Nicks, J J; Naglie, R A

    1986-01-01

    High-frequency jet ventilation using either a proximal or a distal endotracheal injection site through a triple-lumen endotracheal tube was studied in 10 adult cats. The comparative effects on pulmonary gas exchange, tracheal pressure, heart rate, and blood pressure were examined for each injection site at both high (8-12 pounds per square inch [PSI] and low (5-8 PSI) jet-driving pressures in normal and lung-injured cats. Lung injury was created by modification of a surfactant washout technique previously demonstrated in rabbits. Alveolar ventilation (PaCO2) was found to be significantly better with distal than with proximal jet injection under all experimental conditions. At high jet-driving pressures, peak inspiratory pressure was higher in both normal (p = 0.03) and lung-injured cats (p = 0.002) with distal high-frequency jet ventilation. In addition, lung-injured animals were observed to have higher distal mean airway pressures at high jet-driving pressures (p less than 0.01). No differences in oxygenation were found in any circumstances. The results of this animal study suggest that distal high-frequency jet ventilation may be more effective in those situations in which improvement in alveolar ventilation is the major goal and that during proximal high-frequency jet ventilation airway pressures should be monitored as far distally as possible.

  19. Utilization of the organ care system as ex-vivo lung perfusion after cold storage transportation.

    PubMed

    Mohite, P N; Maunz, O; Popov, A-F; Zych, B; Patil, N P; Simon, A R

    2015-11-01

    The Organ Care System (OCS) allows perfusion and ventilation of the donor lungs under physiological conditions. Ongoing trials to compare preservation with OCS Lung with standard cold storage do not include donor lungs with suboptimal gas exchange and donor lungs treated with OCS following cold storage transportation. We present a case of a 48-yr-old man who received such lungs after cold storage transportation treated with ex-vivo lung perfusion utilizing OCS.

  20. Deposition of Aerosols in the Lung: Physiological Factors

    EPA Science Inventory

    Ventilation and mechanics of breathing are an integral part of respiratory physiology that directly affect aerosol transport and deposition in the lung. Although natural breathing pattern varies widely among individuals, breathing pattern is controllable, and by using an appropri...

  1. Brain Injury in Chronically Ventilated Preterm Neonates: Collateral Damage Related to Ventilation Strategy

    PubMed Central

    Albertine, Kurt H.

    2012-01-01

    Synopsis Brain injury is a frequent co-morbidity in chronically ventilated preterm infants. However, the molecular basis of the brain injury remains incompletely understood. The focus of this paper is the subtler (diffuse) form of brain injury that has white matter and gray matter lesions, without germinal matrix hemorrhage-intraventricular hemorrhage, posthemorrhagic hydrocephalus, or cystic periventricular leukomalacia. The purpose of this review is to synthesize data that suggest diffuse lesions to white matter and gray matter are collateral damage related to ventilator strategy. Evidence is introduced from the two large-animal, physiological models of evolving neonatal chronic lung disease that suggest an epigenetic mechanism may underlie the collateral damage. PMID:22954278

  2. Clinical ventilation imaging with In-113m aerosol: a comparison with Kr-81m

    SciTech Connect

    Fazio, F.; Wollmer, P.; Lavender, J.P.; Barr, M.M.

    1982-04-01

    Following routine ventilation (Kr-81m)/perfusion (Tc-99m) scanning, we obtained aerosol ventilation scans using a solution of In-113m albumin and a settling-bag system. The large-volume settling bag reduces deposition of particles in the large airway by removing large droplets. The patient inhales the aerosol with 5-10 min of tidal breathing, then lung scans are obtained on a gamma camera. The energy of In-113m allows the ventilation scanning to be performed after Tc-99m perfusion scanning. Semiquantitative scoring of regional ventilation showed a close correlation (r = 0.97) between Kr-81m and In-113m aerosol ventilation scans. The aerosol technique gave a slight underestimation of ventilation compared with Kr-81m. This is explained by a slightly reduced penetration of particles to the periphery of the lung in patients with severe obstructive airways disease. In all cases, however, the aerosol did visualize all ventilated regions. The results indicate that this readily available aerosol technique can be useful for clinical ventilation imaging in multiple views.

  3. Radionuclide evaluation of lung trauma

    SciTech Connect

    Lull, R.J.; Tatum, J.L.; Sugerman, H.J.; Hartshorne, M.F.; Boll, D.A.; Kaplan, K.A.

    1983-07-01

    Nuclear medicine imaging procedures can play a significant role in evaluating the pulmonary complications that are seen in trauma patients. A quantitative method for measuring increased pulmonary capillary permeability that uses Tc-99m HSA allows early diagnosis of acute respiratory distress syndrome (ARDS) and accurately differentiates this condition from pneumonia or cardiogenic pulmonary edema. This technique may be of great value in following the response to therapy. The use of 133Xe to diagnose inhalation injury remains an important diagnostic tool, particularly at hospitals with specialized burn units. Regional decreases in ventilation-perfusion images reliably localize aspirated foreign bodies. Radionuclide techniques that are used to demonstrate gastropulmonary aspiration remain controversial and require further clinical evaluation. Pulmonary perfusion imaging, although nonspecific, may provide the earliest clue for correct diagnosis of fat embolism, air embolism, contusion, or laceration. Furthermore, the possibility of perfusion abnormality due to these uncommon conditions must be remembered whenever trauma patients are evaluated for pulmonary thromboembolism with scintigraphy. Occasionally, liver or spleen scintigraphy may be the most appropriate procedure when penetrating chest trauma also involves these subdiaphragmatic organs.

  4. Renal scintigraphy following angiotensin converting enzyme inhibition in the diagnosis of renovascular hypertension (captopril scintigraphy)

    SciTech Connect

    Sfakianakis, G.N. )

    1989-09-01

    This article describes the pathophysiology and primary causes of renovascular hypertension (RVH). No historical or physical finding is specific in the diagnosis of RVH, although onset of hypertension before the age of 30 years may suggest the possible presence of RVH. The physiology of the kidney is described along with the biochemistry of angiotensin converting enzyme inhibitors. The main thrust of the article is nuclear medicine techniques useful in the diagnosis of this disease. Several diagnositic methods are described but captopril scintigraphy is presented as a method that may give more optimal results in the diagnosis of RVH.

  5. ASHRAE and residential ventilation

    SciTech Connect

    Sherman, Max H.

    2003-10-01

    In the last quarter of a century, the western world has become increasingly aware of environmental threats to health and safety. During this period, people psychologically retreated away from outdoors hazards such as pesticides, smog, lead, oil spills, and dioxin to the seeming security of their homes. However, the indoor environment may not be healthier than the outdoor environment, as has become more apparent over the past few years with issues such as mold, formaldehyde, and sick-building syndrome. While the built human environment has changed substantially over the past 10,000 years, human biology has not; poor indoor air quality creates health risks and can be uncomfortable. The human race has found, over time, that it is essential to manage the indoor environments of their homes. ASHRAE has long been in the business of ventilation, but most of the focus of that effort has been in the area of commercial and institutional buildings. Residential ventilation was traditionally not a major concern because it was felt that, between operable windows and envelope leakage, people were getting enough outside air in their homes. In the quarter of a century since the first oil shock, houses have gotten much more energy efficient. At the same time, the kinds of materials and functions in houses changed in character in response to people's needs. People became more environmentally conscious and aware not only about the resources they were consuming but about the environment in which they lived. All of these factors contributed to an increasing level of public concern about residential indoor air quality and ventilation. Where once there was an easy feeling about the residential indoor environment, there is now a desire to define levels of acceptability and performance. Many institutions--both public and private--have interests in Indoor Air Quality (IAQ), but ASHRAE, as the professional society that has had ventilation as part of its mission for over 100 years, is the

  6. Respiratory syncytial virus infection in children admitted to hospital but ventilated mechanically for other reasons.

    PubMed

    von Renesse, Anja; Schildgen, Oliver; Klinkenberg, Dennis; Müller, Andreas; von Moers, Arpad; Simon, Arne

    2009-01-01

    One thousand five hundred sixty-eight RSV infections were documented prospectively in 1,541 pediatric patients. Of these, 20 (1.3%) had acquired the RSV infection while treated by mechanical ventilation for reasons other than the actual RSV infection (group ventilated mechanically). The clinical characteristics of children who were infected with respiratory syncytial virus (RSV) infection while ventilated mechanically for other reasons are described and compared with a matched control group. Sixty percent of the group ventilated mechanically had at least one additional risk factor for a severe course of infection (prematurity 50%, chronic lung disease 20%, congenital heart disease 35%, immunodeficiency 20%). The median age at diagnosis in the group ventilated mechanically was 4.2 months. The matched pairs analysis (group ventilated mechanically vs. control group) revealed a higher proportion of patients with hypoxemia and apnoea in the group ventilated mechanically; more patients in the control group showed symptoms of airway obstruction (wheezing). At least one chest radiography was performed in 95% of the patients (n = 19) in the group ventilated mechanically versus 45% (n = 9) in the control group (P = 0.001). The frequency of pneumonia was 40% in the group ventilated mechanically and 20% in the control group. Despite existing consensus recommendations, only two patients (10%) of the group ventilated mechanically had received palivizumab previously. Significantly more patients in the group ventilated mechanically received antibiotic treatment (85% vs. 45%, P = 0.008), and attributable mortality was higher in the group ventilated mechanically (15% [n = 3] vs. 0% in the control group, P = 0.231). Children treated by long term mechanical ventilation may acquire RSV infection by transmission by droplets or caregivers and face an increased risk of a severe course of RSV infection. The low rate of immunoprophylaxis in this particular risk group should be improved.

  7. Lung Emergencies

    MedlinePlus

    ... Emergencies Cardiac Emergencies Eye Emergencies Lung Emergencies Surgeries Lung Emergencies People with Marfan syndrome can be at ... should be considered an emergency. Symptoms of sudden lung collapse (pneumothorax) Symptoms of a sudden lung collapse ...

  8. Lung Cancer

    MedlinePlus

    ... version of this page please turn Javascript on. Lung Cancer What is Lung Cancer? How Tumors Form The body is made ... button on your keyboard.) Two Major Types of Lung Cancer There are two major types of lung ...

  9. Lung metastases

    MedlinePlus

    Metastases to the lung; Metastatic cancer to the lung ... Metastatic tumors in the lungs are cancers that developed at other places in the body (or other parts of the lungs) and spread through the ...

  10. DEA based neonatal lung simulator

    NASA Astrophysics Data System (ADS)

    Schlatter, Samuel; Haemmerle, Enrico; Chang, Robin; O'Brien, Benjamin M.; Gisby, Todd; Anderson, Iain

    2011-04-01

    To reduce the likelihood of ventilator induced lung injury a neonatal lung simulator is developed based on Dielectric Elastomer Actuators (DEAs). DEAs are particularly suited for this application due to their natural like response as well as their self-sensing ability. By actively controlling the DEA, the pressure and volume inside the lung simulator can be controlled giving rise to active compliance control. Additionally the capacitance of the DEA can be used as a measurement of volume eliminating the integration errors that plague flow sensors. Based on simulations conducted with the FEA package ABAQUS and experimental data, the characteristics of the lung simulator were explored. A relationship between volume and capacitance was derived based on the self sensing of a bubble actuator. This was then used to calculate the compliance of the experimental bubble actuator. The current results are promising and show that mimicking a neonatal lung with DEAs may be possible.

  11. Lung Parenchymal Mechanics

    PubMed Central

    Suki, Béla; Stamenovic, Dimitrije; Hubmayr, Rolf

    2014-01-01

    The lung parenchyma comprises a large number of thin-walled alveoli, forming an enormous surface area, which serves to maintain proper gas exchange. The alveoli are held open by the transpulmonary pressure, or prestress, which is balanced by tissues forces and alveolar surface film forces. Gas exchange efficiency is thus inextricably linked to three fundamental features of the lung: parenchymal architecture, prestress, and the mechanical properties of the parenchyma. The prestress is a key determinant of lung deformability that influences many phenomena including local ventilation, regional blood flow, tissue stiffness, smooth muscle contractility, and alveolar stability. The main pathway for stress transmission is through the extracellular matrix. Thus, the mechanical properties of the matrix play a key role both in lung function and biology. These mechanical properties in turn are determined by the constituents of the tissue, including elastin, collagen, and proteoglycans. In addition, the macroscopic mechanical properties are also influenced by the surface tension and, to some extent, the contractile state of the adherent cells. This article focuses on the biomechanical properties of the main constituents of the parenchyma in the presence of prestress and how these properties define normal function or change in disease. An integrated view of lung mechanics is presented and the utility of parenchymal mechanics at the bedside as well as its possible future role in lung physiology and medicine are discussed. PMID:23733644

  12. Quantitative investigation of alveolar structures with OCT using total liquid ventilation during mechanical ventilation

    NASA Astrophysics Data System (ADS)

    Schnabel, Christian; Gaertner, Maria; Meissner, Sven; Koch, Edmund

    2012-02-01

    To develop new treatment possibilities for patients with severe lung diseases it is crucial to understand the lung function on an alveolar level. Optical coherence tomography (OCT) in combination with intravital microscopy (IVM) are used for imaging subpleural alveoli in animal models to gain information about dynamic and morphological changes of lung tissue during mechanical ventilation. The image content suitable for further analysis is influenced by image artifacts caused by scattering, refraction, reflection, and absorbance. Because the refractive index varies with each air-tissue interface in lung tissue, these effects decrease OCT image quality exceedingly. The quality of OCT images can be increased when the refractive index inside the alveoli is matched to the one of tissue via liquid-filling. Thereby, scattering loss can be decreased and higher penetration depth and tissue contrast can be achieved. To use the advantages of liquid-filling for in vivo imaging of small rodent lungs, a suitable breathing fluid (perfluorodecalin) and a special liquid respirator are necessary. Here we show the effect of liquid-filling on OCT and IVM image quality of subpleural alveoli in a mouse model.

  13. Efficiency index: a new parameter to define breathing patterns during dynamic Xe-127 ventilation studies

    SciTech Connect

    Slosman, D.; Susskind, H.; Bossuyt, A.; Tang, Y.N.; Brill, A.B.

    1986-03-01

    Ventilation imaging can be improved by gating scintigraphic data with the respiratory cycle using temporal Fourier analysis (TFA) to quantify the temporal behavior of the ventilation. Sixteen consecutive images, representing equal-time increments of an average respiratory cycle, were produced by TFA in the posterior view on a pixel-by-pixel basis. An Efficiency Index (EFF), defined as the ratio of the summation of all the differences between maximum and minimum counts for each pixel to that for the entire lung during the respiratory cycle, was derived to describe the pattern of ventilation. The gated ventilation studies were carried out with Xe-127 in 12 subjects: normal lung function (4), small airway disease (2), COPD (5), and restrictive disease (1). EFF for the first three harmonics correlated linearly with FEV1 (r = 0.701, p< 0.01). This approach is suggested as a very sensitive method to quantify the extent and regional distribution of airway obstruction.

  14. Innovations in mechanical ventilation.

    PubMed

    Branson, Richard D; Johannigman, Jay A

    2009-07-01

    New features of mechanical ventilators are frequently introduced, including new modes, monitoring techniques, and triggering techniques. But new rarely translates into any measureable improvement in outcome. We describe 4 new techniques and attempt to define what is a new invention versus what is innovative-a technique that significantly improves a measurable variable. We describe and review the literature on automated weaning, automated measurement of functional residual capacity, neural triggering, and novel displays of respiratory mechanics. PMID:19558743

  15. Oven ventilation system

    SciTech Connect

    Brewer, D.E.

    1987-02-17

    A ventilation system is described for venting an oven with external surfaces, the oven being located within an enclosed space, the system comprising: intake means for collecting air from the external environment of the enclosed space; means for forming a sheet of the air and passing the sheet across the external surfaces of the oven; and exhaust means for exhausting the sheet of the air to the external environment of the enclosed space after the air has been passed across the external surfaces.

  16. Lung cancer

    SciTech Connect

    Aisner, J.

    1985-01-01

    This book contains 13 chapters. Some of the chapter titles are: The Pathology of Lung Cancer; Radiotherapy for Non-Small-Cell Cancer of the Lung; Chemotherapy for Non-Small-Cell Lung Cancer; Immunotherapy in the Management of Lung Cancer; Preoperative Staging and Surgery for Non-Small-Cell Lung Cancer; and Prognostic Factors in Lung Cancer.

  17. Exhaled breath condensate collection in the mechanically ventilated patient.

    PubMed

    Carter, Stewart R; Davis, Christopher S; Kovacs, Elizabeth J

    2012-05-01

    Collection of exhaled breath condensate (EBC) is a non-invasive means of sampling the airway-lining fluid of the lungs. EBC contains numerous measurable mediators, whose analysis could change the management of patients with certain pulmonary diseases. While initially popularized in investigations involving spontaneously breathing patients, an increasing number of studies have been performed using EBC in association with mechanical ventilation. Collection of EBC in mechanically ventilated patients follows basic principles of condensation, but is influenced by multiple factors. Effective collection requires selection of a collection device, adequate minute ventilation, low cooling temperatures, and sampling times of greater than 10 min. Condensate can be contaminated by saliva, which needs to be filtered. Dilution of samples occurs secondary to distilled water in vapors and humidification in the ventilator circuit. Dilution factors may need to be employed when investigating non-volatile biomarkers. Storage and analysis should occur promptly at -70 °C to -80 °C to prevent rapid degradation of samples. The purpose of this review is to examine and describe methodologies and problems of EBC collection in mechanically ventilated patients. A straightforward and safe framework has been established to investigate disease processes in this population, yet technical aspects of EBC collection still exist that prevent clinical practicality of this technology. These include a lack of standardization of procedure and analysis of biomarkers, and of normal reference ranges for mediators in healthy individuals. Once these procedural aspects have been addressed, EBC could serve as a non-invasive alternative to invasive evaluation of lungs in mechanically ventilated patients.

  18. Convective mixing mechanisms in high frequency intermittent jet ventilation.

    PubMed

    Scherer, P W; Muller, W J; Raub, J B; Haselton, F R

    1989-01-01

    A liquid flow visualization technique was used to identify the location of neutrally buoyant bead clouds injected into airway models during flows simulating high frequency intermittent jet ventilation (HFIJV) in neonatal lungs. The motions of these bead clouds show that the convective or bulk mixing that occurs during HFIJV is made up of two parts; a turbulent convective exchange with the atmosphere caused by the jet in the trachea and a streaming motion along the airways driven by an interaction between the jet and the expansion and contraction of the airways due to their compliance. These convective streaming motions combine with molecular diffusion to produce augmented diffusion which transports O2 and CO2 between the trachea and the peripheral alveoli. Optimizing HFIJV (as well as other forms of HFV) depends on maximizing these airway convective streaming flows which depend on many more lung and fluid mechanical parameters than are necessary to describe conventional mechanical ventilation.

  19. Percutaneous Transtracheal Jet Ventilation with Various Upper Airway Obstruction

    PubMed Central

    Doi, Tomoki; Miyashita, Tetsuya; Furuya, Ryousuke; Sato, Hitoshi; Takaki, Shunsuke; Goto, Takahisa

    2015-01-01

    A “cannot-ventilate, cannot-intubate” situation is critical. In difficult airway management, transtracheal jet ventilation (TTJV) has been recommended as an invasive procedure, but specialized equipment is required. However, the influence of upper airway resistance (UAR) during TTJV has not been clarified. The aim of this study was to compare TTJV using a manual jet ventilator (MJV) and the oxygen flush device of the anesthetic machine (AM). We made a model lung offering variable UAR by adjustment of tracheal tube size that can ventilate through a 14-G cannula. We measured side flow due to the Venturi effect during TTJV, inspired tidal volume (TVi), and expiratory time under various inspiratory times. No Venturi effect was detected during TTJV with either device. With the MJV, TVi tended to increase in proportion to UAR. With AM, significant variations in TVi was not detected with changes in any UAR. In conclusion, UAR influenced forward flow of TTJV in the model lung. The influence of choked flow from the Venturi effect was minimal under all UAR settings with the MJV, but the AM could not deliver sufficient flow. PMID:26161402

  20. Iloprost drug delivery during infant conventional and high-frequency oscillatory ventilation.

    PubMed

    DiBlasi, Robert M; Crotwell, Dave N; Shen, Shuijie; Zheng, Jiang; Fink, James B; Yung, Delphine

    2016-03-01

    Iloprost is a selective pulmonary vasodilator approved for inhalation by the Food and Drug Administration. Iloprost has been increasingly used in the management of critically ill neonates with hypoxic lung disease. This in vitro study was designed to test the hypothesis that aerosol drug delivery could be effectively administered to infants with both conventional ventilation and high-frequency oscillatory ventilation (HFOV). A neonatal test lung model configured with newborn lung mechanics was ventilated with a conventional ventilator and an HFOV with standard settings. A vibrating-mesh nebulizer was placed (1) proximal to the patient airway in the inspiratory limb between the humidifier probe and patient wye (conventional) as well as between the vent circuit and the endotracheal tube (ETT) for HFOV and (2) between the ventilator and humidifier (distal). Iloprost was nebulized in three separate runs using three new nebulizers in each of the circuit locations. A collecting filter was placed at the distal end of the ETT for each trial. Iloprost was quantified using high-performance liquid chromatography. The percentage of nominal dose delivered was greater with the nebulizer placed proximal to the airway for conventional ventilation (10.74% ± 2%) and HFOV (29% ± 2%) than with it placed in the distal position (2.96% ± 0.2% vs. 0.96% ± 0.8%, respectively; P < 0.05). Drug delivery in proximal position was nearly threefold greater during HFOV than during conventional ventilation. In conclusion, iloprost drug delivery was best achieved when the nebulizer was placed proximal to the patient airway during neonatal mechanical ventilation. Drug delivery appears to be more efficient during HFOV than during conventional ventilation.

  1. Iloprost drug delivery during infant conventional and high-frequency oscillatory ventilation.

    PubMed

    DiBlasi, Robert M; Crotwell, Dave N; Shen, Shuijie; Zheng, Jiang; Fink, James B; Yung, Delphine

    2016-03-01

    Iloprost is a selective pulmonary vasodilator approved for inhalation by the Food and Drug Administration. Iloprost has been increasingly used in the management of critically ill neonates with hypoxic lung disease. This in vitro study was designed to test the hypothesis that aerosol drug delivery could be effectively administered to infants with both conventional ventilation and high-frequency oscillatory ventilation (HFOV). A neonatal test lung model configured with newborn lung mechanics was ventilated with a conventional ventilator and an HFOV with standard settings. A vibrating-mesh nebulizer was placed (1) proximal to the patient airway in the inspiratory limb between the humidifier probe and patient wye (conventional) as well as between the vent circuit and the endotracheal tube (ETT) for HFOV and (2) between the ventilator and humidifier (distal). Iloprost was nebulized in three separate runs using three new nebulizers in each of the circuit locations. A collecting filter was placed at the distal end of the ETT for each trial. Iloprost was quantified using high-performance liquid chromatography. The percentage of nominal dose delivered was greater with the nebulizer placed proximal to the airway for conventional ventilation (10.74% ± 2%) and HFOV (29% ± 2%) than with it placed in the distal position (2.96% ± 0.2% vs. 0.96% ± 0.8%, respectively; P < 0.05). Drug delivery in proximal position was nearly threefold greater during HFOV than during conventional ventilation. In conclusion, iloprost drug delivery was best achieved when the nebulizer was placed proximal to the patient airway during neonatal mechanical ventilation. Drug delivery appears to be more efficient during HFOV than during conventional ventilation. PMID:27162615

  2. Quantification of regional ventilation in humans using a short-lived radiotracer--theoretical evaluation of the steady-state model

    SciTech Connect

    Valind, S.O.; Rhodes, C.G.; Jonson, B.

    1987-07-01

    The accuracy of the steady-state measurement of ventilation by means of a short-lived insoluble inert gas tracer rests with the validity of the steady-state flow equation. This has previously been applied to the qualitative assessment of regional ventilation using krypton-81m, but may potentially be used for the calculation of regional alveolar ventilation per unit alveolar gas volume--(VA/VA)cal--from measurements of the alveolar concentration of the tracer. The steady-state alveolar tracer concentration was calculated for the course of a breathing cycle, using a lung model featuring airways dead space and tidal gas flow. The calculations were made by computer simulations of a lung, characterized by predefined values of parameters describing the lung structure and the mode of ventilation. In the normal lung of supine man at rest (specific alveolar ventilation, ranging from 1.0 to 3.5 min-1) the errors of (VA/VA)cal relative to the predefined true values range from an overestimation by some 3% in the low ventilation regions to an underestimation by 8% in the best ventilated regions. The errors mainly result from ventilation of the airways dead space, which will influence the distribution of tracer in the lung by the transfer of tracer between regions by way of the common dead space and by the decay of tracer during its transport through the bronchial tree.

  3. Optimal Delivery of Aerosols to Infants During Mechanical Ventilation

    PubMed Central

    Azimi, Mandana; Hindle, Michael

    2014-01-01

    Abstract Purpose: The objective of this study was to determine optimal aerosol delivery conditions for a full-term (3.6 kg) infant receiving invasive mechanical ventilation by evaluating the effects of aerosol particle size, a new wye connector, and timing of aerosol delivery. Methods: In vitro experiments used a vibrating mesh nebulizer and evaluated drug deposition fraction and emitted dose through ventilation circuits containing either a commercial (CM) or new streamlined (SL) wye connector and 3-mm endotracheal tube (ETT) for aerosols with mass median aerodynamic diameters of 880 nm, 1.78 μm, and 4.9 μm. The aerosol was released into the circuit either over the full inhalation cycle (T1 delivery) or over the first half of inhalation (T2 delivery). Validated computational fluid dynamics (CFD) simulations and whole-lung model predictions were used to assess lung deposition and exhaled dose during cyclic ventilation. Results: In vitro experiments at a steady-state tracheal flow rate of 5 L/min resulted in 80–90% transmission of the 880-nm and 1.78-μm aerosols from the ETT. Based on CFD simulations with cyclic ventilation, the SL wye design reduced depositional losses in the wye by a factor of approximately 2–4 and improved lung delivery efficiencies by a factor of approximately 2 compared with the CM device. Delivery of the aerosol over the first half of the inspiratory cycle (T2) reduced exhaled dose from the ventilation circuit by a factor of 4 compared with T1 delivery. Optimal lung deposition was achieved with the SL wye connector and T2 delivery, resulting in 45% and 60% lung deposition for optimal polydisperse (∼1.78 μm) and monodisperse (∼2.5 μm) particle sizes, respectively. Conclusions: Optimization of selected factors and use of a new SL wye connector can substantially increase the lung delivery efficiency of medical aerosols to infants from current values of <1–10% to a range of 45–60%. PMID:24299500

  4. [Lung pneumatocele in adult patient - case report].

    PubMed

    Dzian, A; Fúčela, I; Hamžík, J; Huťka, Z; Stiegler, P

    2012-12-01

    Lung pneumatoceles are characterized by a thin-walled air-filled cavity present in lung parenchyma. Mostly they are the result of acute bronchopneumonia after spontaneous drainage of altered lung parenchyma with subsequent development and progression of cavities due to ventile mechanism. This disease is more prevalent in infants and young children, it is rather rare in adults. In the present case report, videothoracoscopy resection of lung pneumatocele of the right lower lobe was performed a 43-years old man. The operation was indicated for the presence of chronic persisting and progressing pneumatocele as a preventive measure of pneumatocele complications. PMID:23448707

  5. A significant diagnostic method in torture investigation: bone scintigraphy.

    PubMed

    Ozkalipci, Onder; Unuvar, Umit; Sahin, Umit; Irencin, Sukran; Fincanci, Sebnem Korur

    2013-03-10

    Torture appears to be a permanent feature in countries, which have experienced military coups or ruled by oppressive governments in the past, such as Turkey. The Human Rights Foundation of Turkey (HRFT) was established in 1990 to serve torture victims, mainly those who were the victims of the 1980 military regime. Since then the HRFT has been providing rehabilitation and documentation for torture survivors. Bone scintigraphy can be one of the diagnostic methods to reveal trauma, particularly after several years when it is challenging to find any physical or radiological evidence. The HRFT's Istanbul Branch referred 97 of their applicants for bone scintigraphy between 1992 and 2010. In this retrospective survey of 97 cases, 17 of them were female and 80 of them were male. Several aspects were evaluated, including working conditions, change of torture methods practiced in certain time periods, time since torture and duration of exposure to torture in comparison with findings of bone scintigraphies. The torture methods varied from beating to falanga, electric shock, suspension and several other types of torture within the period of practice, although beating was a common denominator among all. The findings were classified according to time since torture and duration of exposure to torture. More than half of the cases (59%) had a detectable bone lesion on bone scintigraphy, and the detectable bone lesion on scintigraphy increased significantly with the duration of exposure to torture, particularly among cases who had been subjected to torture for a longer period (8 days and more). Bone scintigraphy should be considered as a valuable non-invasive diagnostic method to assess and document long term torture practices and/or cases with no detectable marks upon physical examination.

  6. Respiratory dysfunction in ventilated patients: can inspiratory muscle training help?

    PubMed

    Bissett, B; Leditschke, I A; Paratz, J D; Boots, R J

    2012-03-01

    Respiratory muscle dysfunction is associated with prolonged and difficult weaning from mechanical ventilation. This dysfunction in ventilator-dependent patients is multifactorial: there is evidence that inspiratory muscle weakness is partially explained by disuse atrophy secondary to ventilation, and positive end-expiratory pressure can further reduce muscle strength by negatively shifting the length-tension curve of the diaphragm. Polyneuropathy is also likely to contribute to apparent muscle weakness in critically ill patients, and nutritional and pharmaceutical effects may further compound muscle weakness. Moreover, psychological influences, including anxiety, may contribute to difficulty in weaning. There is recent evidence that inspiratory muscle training is safe and feasible in selected ventilator-dependent patients, and that this training can reduce the weaning period and improve overall weaning success rates. Extrapolating from evidence in sports medicine, as well as the known effects of inspiratory muscle training in chronic lung disease, a theoretical model is proposed to describe how inspiratory muscle training enhances weaning and recovery from mechanical ventilation. Possible mechanisms include increased protein synthesis (both Type 1 and Type 2 muscle fibres), enhanced limb perfusion via dampening of a sympathetically-mediated metaboreflex, reduced lactate levels and modulation of the perception of exertion, resulting in less dyspnoea and enhanced exercise capacity.

  7. Distribution of pulmonary ventilation and perfusion during short periods of weightlessness

    NASA Technical Reports Server (NTRS)

    Michels, D. B.; West, J. B.

    1978-01-01

    Airborne experiments were conducted on four trained normal male subjects (28-40 yr) to study pulmonary function during short periods (22-27 sec) of zero gravity obtained by flying a jet aircraft through appropriate parabolic trajectories. The cabin was always pressurized to a sea-level altitude. The discussion is limited to pulmonary ventilation and perfusion. The results clearly demonstrate that gravity is the major factor causing nonuniformity in the topographical distribution of pulmonary ventilation. More importantly, the results suggest that virtually all the topographical nonuniformity of ventilation, blood flow, and lung volume observed under 1-G conditions are eliminated during short periods of zero gravity.

  8. Testis Scintigraphy in a Patient with Acute Lymphoblastic Leukemia

    PubMed Central

    Şencan Eren, Mine; Koç, Murat; Ören, Hale; Özkal, Şermin; Durak, Hatice

    2014-01-01

    Acute lymphoblastic leukemia (ALL) is a pediatric malignancy associated with remissions and relapses. Common relapsing sitesare meninges, testis and ovary. Testicular scintigraphy is a highly specific modality used mainly in the differential diagnosis of testicular torsion and epidydimitis/epidydimo-orchitis. There is only one interesting image on leukemic infiltration with scrotal scintigraphy in the literature. The aim of this case presentation is to report that although the scintigraphic appearance of testicular torsion was observed in a patient with the diagnosis of ALL, testicular ALL infiltration was revealed in pathologic examination. Conflict of interest:None declared. PMID:24653935

  9. Congenital lung lesions: Postnatal management and outcome.

    PubMed

    Parikh, Dakshesh H; Rasiah, Shree Vishna

    2015-08-01

    Antenatal diagnosis of lung lesion has become more accurate resulting in dilemma and controversies of its antenatal and postnatal management. Majority of antenatally diagnosed congenital lung lesions are asymptomatic in the neonatal age group. Large lung lesions cause respiratory compromise and inevitably require urgent investigations and surgery. The congenital lung lesion presenting with hydrops requires careful postnatal management of lung hypoplasia and persistent pulmonary hypertension. Preoperative stabilization with gentle ventilation with permissive hypercapnia and delayed surgery similar to congenital diaphragmatic hernia management has been shown to result in good outcome. The diagnostic investigations and surgical management of the asymptomatic lung lesions remain controversial. Postnatal management and outcome of congenital cystic lung lesions are discussed. PMID:26051048

  10. New modes of mechanical ventilation: proportional assist ventilation, neurally adjusted ventilatory assist, and fractal ventilation.

    PubMed

    Navalesi, Paolo; Costa, Roberta

    2003-02-01

    Increased knowledge of the mechanisms that determine respiratory failure has led to the development of new technologies aimed at improving ventilatory treatment. Proportional assist ventilation and neurally adjusted ventilatory assist have been designed with the goal of improving patient-ventilator interaction by matching the ventilator support with the neural output of the respiratory centers. With proportional assist ventilation, the support is continuously readjusted in proportion to the predicted inspiratory effort. Neurally adjusted ventilatory assist is an experimental mode in which the assistance is delivered in proportion to the electrical activity of the diaphragm, assessed by means of an esophageal electrode. Biologically variable (or fractal) ventilation is a new, volume-targeted, controlled ventilation mode aimed at improving oxygenation; it incorporates the breath-to-breath variability that characterizes a natural breathing pattern.

  11. Accuracy of delivered versus preset minute ventilation of portable emergency ventilators.

    PubMed

    Heinrichs, W; Mertzlufft, F; Dick, W

    1989-07-01

    The accuracy of delivered minute volume (VE) ventilation of portable emergency ventilators (PEV) was evaluated. Five PEV from three manufacturers were adapted to an artificial lung for varying compliance and resistance. Each PEV was tested in the "no airmix" (pure oxygen) and "airmix" (approximately 60% oxygen) setting at different frequencies and VE. Measurement of delivered VE (VEdel) was made using a pneumotachograph and digital integration of the flow values greater than 1 min (maximal error +/- 2%). Maximal inspiratory pressure (Pinsp) was measured with a transducer. Two PEV from one manufacturer produced severe hyperventilation when used at low VE (i.e., in children). Two other PEV from another manufacturer produced less marked hyperventilation, but revealed unexpected hypoventilation during conditions of higher inspiratory pressures (i.e., in adults with reduced compliance). The prototype PEV that was tested also revealed less marked hyperventilation with small decreases (down to -10% of the VE at higher Pinsp values). Further investigation is needed before this prototype goes into production. Manufacturers should redefine predicted values or machine settings or indicate that use of these devices may produce results which are not in accordance with the machine settings. Until adjustments are made, ventilation should be monitored when possible by measurement of end-tidal PCO2 or systemic arterial blood gases. PMID:2736931

  12. Laboratory and Industrial Ventilation

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This handbook supplements the Facilities Engineering Handbook (NHB 7320.1) and provides additional policies and criteria for uniform application to ventilation systems. It expands basic requirements, provides additional design and construction guidance, and places emphasis on those design considerations which will provide for greater effectiveness in the use of these systems. The provisions of this handbook are applicable to all NASA field installations and the Jet Propulsion Laboratory. Since supply of this handbook is limited, abstracts of the portion or portions applicable to a given requirement will be made for the individual specific needs encountered rather than supplying copies of the handbook as has been past practice.

  13. Ventilation best practices guide

    SciTech Connect

    Dorgan, C.B.; Dorgan, C.E.

    1996-07-01

    The intent of this Guide is to provide utility marketing and engineering personnel with information on how to identify indoor air quality (IAQ) problems, the current standards relating to IAQ and examples of what typically causes IAQ problems in commercial buildings. The Guide is written assuming that the reader has limited knowledge of heating, ventilating and air conditioning (HVAC) systems and that they are new to the IAQ arena. Also included in the Guide is a discussion of new electric technologies which are energy efficient and maintain a high level of IAQ.

  14. Humidification for ventilated patients.

    PubMed

    Ballard, K; Cheeseman, W; Ripiner, T; Wells, S

    1992-03-01

    When a patient is intubated with an endotracheal tube for artificial ventilation the humidifying, warming and filtering functions of the nose and upper airways are bypassed. This article reviews the need for the provision of artificial humidification, optimal levels that should be provided and the two types of device which are available to achieve this, namely, the heat and moisture exchanging devices and the heated vaporising or nebulising humidifiers. Finally a study is presented which documents the exact level of moisture delivered to patients by the cascade water bath humidifier.

  15. 21 CFR 868.5975 - Ventilator tubing.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... Ventilator tubing is a device intended for use as a conduit for gases between a ventilator and a patient during ventilation of the patient. (b) Classification. Class I (general controls). The device is...

  16. Bioreactor Development for Lung Tissue Engineering

    PubMed Central

    Panoskaltsis-Mortari, Angela

    2015-01-01

    Rationale Much recent interest in lung bioengineering by pulmonary investigators, industry and the organ transplant field has seen a rapid growth of bioreactor development ranging from the microfluidic scale to the human-sized whole lung systems. A comprehension of the findings from these models is needed to provide the basis for further bioreactor development. Objective The goal was to comprehensively review the current state of bioreactor development for the lung. Methods A search using PubMed was done for published, peer-reviewed papers using the keywords “lung” AND “bioreactor” or “bioengineering” or “tissue engineering” or “ex vivo perfusion”. Main Results Many new bioreactors ranging from the microfluidic scale to the human-sized whole lung systems have been developed by both academic and commercial entities. Microfluidic, lung-mimic and lung slice cultures have the advantages of cost-efficiency and high throughput analyses ideal for pharmaceutical and toxicity studies. Perfused/ventilated rodent whole lung systems can be adapted for mid-throughput studies of lung stem/progenitor cell development, cell behavior, understanding and treating lung injury and for preliminary work that can be translated to human lung bioengineering. Human-sized ex vivo whole lung bioreactors incorporating perfusion and ventilation are amenable to automation and have been used for whole lung decellularization and recellularization. Clinical scale ex vivo lung perfusion systems have been developed for lung preservation and reconditioning and are currently being evaluated in clinical trials. Conclusions Significant advances in bioreactors for lung engineering have been made at both the microfluidic and the macro scale. The most advanced are closed systems that incorporate pressure-controlled perfusion and ventilation and are amenable to automation. Ex vivo lung perfusion systems have advanced to clinical trials for lung preservation and reconditioning. The biggest

  17. Effects of surfactant depletion on regional pulmonary metabolic activity during mechanical ventilation.

    PubMed

    de Prost, Nicolas; Costa, Eduardo L; Wellman, Tyler; Musch, Guido; Winkler, Tilo; Tucci, Mauro R; Harris, R Scott; Venegas, Jose G; Vidal Melo, Marcos F

    2011-11-01

    Inflammation during mechanical ventilation is thought to depend on regional mechanical stress. This can be produced by concentration of stresses and cyclic recruitment in low-aeration dependent lung. Positron emission tomography (PET) with (18)F-fluorodeoxyglucose ((18)F-FDG) allows for noninvasive assessment of regional metabolic activity, an index of neutrophilic inflammation. We tested the hypothesis that, during mechanical ventilation, surfactant-depleted low-aeration lung regions present increased regional (18)F-FDG uptake suggestive of in vivo increased regional metabolic activity and inflammation. Sheep underwent unilateral saline lung lavage and were ventilated supine for 4 h (positive end-expiratory pressure = 10 cmH(2)O, tidal volume adjusted to plateau pressure = 30 cmH(2)O). We used PET scans of injected (13)N-nitrogen to compute regional perfusion and ventilation and injected (18)F-FDG to calculate (18)F-FDG uptake rate. Regional aeration was quantified with transmission scans. Whole lung (18)F-FDG uptake was approximately two times higher in lavaged than in nonlavaged lungs (2.9 ± 0.6 vs. 1.5 ± 0.3 10(-3)/min; P < 0.05). The increased (18)F-FDG uptake was topographically heterogeneous and highest in dependent low-aeration regions (gas fraction 10-50%, P < 0.001), even after correction for lung density and wet-to-dry lung ratios. (18)F-FDG uptake in low-aeration regions of lavaged lungs was higher than that in low-aeration regions of nonlavaged lungs (P < 0.05). This occurred despite lower perfusion and ventilation to dependent regions in lavaged than nonlavaged lungs (P < 0.001). In contrast, (18)F-FDG uptake in normally aerated regions was low and similar between lungs. Surfactant depletion produces increased and heterogeneously distributed pulmonary (18)F-FDG uptake after 4 h of supine mechanical ventilation. Metabolic activity is highest in poorly aerated dependent regions, suggesting local increased inflammation.

  18. Biophysical determinants of alveolar epithelial plasma membrane wounding associated with mechanical ventilation.

    PubMed

    Hussein, Omar; Walters, Bruce; Stroetz, Randolph; Valencia, Paul; McCall, Deborah; Hubmayr, Rolf D

    2013-10-01

    Mechanical ventilation may cause harm by straining lungs at a time they are particularly prone to injury from deforming stress. The objective of this study was to define the relative contributions of alveolar overdistension and cyclic recruitment and "collapse" of unstable lung units to membrane wounding of alveolar epithelial cells. We measured the interactive effects of tidal volume (VT), transpulmonary pressure (PTP), and of airspace liquid on the number of alveolar epithelial cells with plasma membrane wounds in ex vivo mechanically ventilated rat lungs. Plasma membrane integrity was assessed by propidium iodide (PI) exclusion in confocal images of subpleural alveoli. Cyclic inflations of normal lungs from zero end-expiratory pressure to 40 cmH2O produced VT values of 56.9 ± 3.1 ml/kg and were associated with 0.12 ± 0.12 PI-positive cells/alveolus. A preceding tracheal instillation of normal saline (3 ml) reduced VT to 49.1 ± 6 ml/kg but was associated with a significantly greater number of wounded alveolar epithelial cells (0.52 ± 0.16 cells/alveolus; P < 0.01). Mechanical ventilation of completely saline-filled lungs with saline (VT = 52 ml/kg) to pressures between 10 and 15 cmH2O was associated with the least number of wounded epithelial cells (0.02 ± 0.02 cells/alveolus; P < 0.01). In mechanically ventilated, partially saline-filled lungs, the number of wounded cells increased substantially with VT, but, once VT was accounted for, wounding was independent of maximal PTP. We found that interfacial stress associated with the generation and destruction of liquid bridges in airspaces is the primary biophysical cell injury mechanism in mechanically ventilated lungs. PMID:23997173

  19. New Ventilated Isolation Cage

    PubMed Central

    Cook, Reginald O.

    1968-01-01

    A multifunction lid has been developed for a commercially available transparent animal cage which permits feeding, watering, viewing, long-term holding, and local transport of laboratory rodents on experiment while isolating the surrounding environment. The cage is airtight except for its inlet and exhaust high-efficiency particulate air filters, and it is completely steam-sterilizable. Opening of the cage's feed and water ports causes an inrush of high velocity air which prevents back-migration of aerosols and permits feeding and watering while eliminating need for chemical vapor decontamination. Ventilation system design permits the holding in adjacent cages of animals infected with different organisms without danger of cross-contamination; leaves the animal room odor-free; reduces required bedding changes to twice a month or less, and provides investigators with capability to control precisely individual cage ventilation rates. Forty-eight cages can be conveniently placed on a standard NIH “shoebox” cage rack (60 inches wide × 28 inches deep × 74 inches high) fitted with a simple manifold exhaust system. The entire system is mobile, requiring only an electrical power outlet. Principal application of the caging system is in the area of preventing exposure of animal caretakers to pathogenic substances associated with the animal host, and in reducing handling of animals and their exposure to extraneous contamination. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 9 PMID:5659368

  20. Transpired Air Collectors - Ventilation Preheating

    SciTech Connect

    Christensen, C.

    2006-06-22

    Many commercial and industrial buildings have high ventilation rates. Although all that fresh air is great for indoor air quality, heating it can be very expensive. This short (2-page) fact sheet describes a technology available to use solar energy to preheat ventilation air and dramatically reduce utility bills.

  1. Ventilation-perfusion matching during exercise

    NASA Technical Reports Server (NTRS)

    Wagner, P. D.

    1992-01-01

    In normal subjects, exercise widens the alveolar-arterial PO2 difference (P[A-a]O2) despite a more uniform topographic distribution of ventilation-perfusion (VA/Q) ratios. While part of the increase in P(A-a)O2 (especially during heavy exercise) is due to diffusion limitation, a considerable amount is caused by an increase in VA/Q mismatch as detected by the multiple inert gas elimination technique. Why this occurs is unknown, but circumstantial evidence suggests it may be related to interstitial pulmonary edema rather than to factors dependent on ventilation, airway gas mixing, airway muscle tone, or pulmonary vascular tone. In patients with lung disease, the gas exchange consequences of exercise are variable. Thus, arterial PO2 may increase, remain the same, or fall. In general, patients with advanced chronic obstructive pulmonary disease (COPD) or interstitial fibrosis who exercise show a fall in PO2. This is usually not due to worsening VA/Q relationships but mostly to the well-known fall in mixed venous PO2, which itself results from a relatively smaller increase in cardiac output than VO2. However, in interstitial fibrosis (but not COPD), there is good evidence that a part of the fall in PO2 on exercise is caused by alveolar-capillary diffusion limitation of O2 transport; in COPD (but not interstitial fibrosis), a frequent additional contributing factor to the hypoxemia of exercise is an inadequate ventilatory response, such that minute ventilation does not rise as much as does CO2 production or O2 uptake, causing arterial PCO2 to increase and PO2 to fall.

  2. Extracorporeal carbon dioxide removal: the future of lung support lies in the history.

    PubMed

    Kaushik, Manish; Wojewodzka-Zelezniakowicz, Marzena; Cruz, Dinna N; Ferrer-Nadal, A; Teixeira, Catarina; Iglesias, Elena; Kim, Jeong Chul; Braschi, Antonio; Piccinni, Pasquale; Ronco, Claudio

    2012-01-01

    Extracorporeal organ support in patients with dysfunction of vital organs like the kidney, heart, and liver has proven helpful in bridging the patients to recovery or more definitive therapy. Mechanical ventilation in patients with respiratory failure, although indispensable, has been associated with worsening injury to the lungs, termed ventilator-induced lung injury. Application of lung-protective ventilation strategies are limited by inevitable hypercapnia and hypercapnic acidosis. Various alternative extracorporeal strategies, proposed more than 30 years ago, to combat hypercapnia are now more readily available. In particular, the venovenous approach to effective carbon dioxide removal, which involves minimal invasiveness comparable to renal replacement therapy, appears to be very promising. The clinical applications of these extracorporeal carbon dioxide removal therapies may extend beyond just lung protection in ventilated patients. This article summarizes the rationale, technology and clinical application of various extracorporeal lung assist techniques available for clinical use, and some of the future perspectives in the field.

  3. Cavernous hemangioma. Why is peripheral filling at scintigraphy so rare

    SciTech Connect

    Drane, W.E.; Weatherby, E. III

    1987-10-01

    Peripheral filling at dynamic CT occurs frequently with cavernous hemangiomas, yet this phenomenon is a rare finding on Tc-99m RBC imaging. A case of peripheral filling of a cavernous hemangioma with scintigraphy is reported and the rationale for its infrequent occurrence is discussed.

  4. /sup 123/I-metaiodobenzylguanidine scintigraphy of ectopic intracranial retinoblastoma

    SciTech Connect

    Bomanji, J.; Kingston, J.E.; Hungerford, J.L.; Britton, K.E.

    1989-01-01

    Radioiodinated metaiodobenzylguanidine (MIBG) has been used for diagnostic purposes to image neural crest tumors. We report the uptake of /sup 123/I MIBG in a child with ectopic intracranial retinoblastoma. It is felt that /sup 123/I MIBG scintigraphy may have a role in detecting occult metastatic disease in these patients.

  5. Accuracy of Hepatobiliary Scintigraphy after Liver Transplantation and Liver Resection

    PubMed Central

    Ackermann, Hanns; Bechstein, Wolf O.; Grünwald, Frank

    2016-01-01

    Background and Aims. Biliary complications are the most frequent complications after common liver surgeries. In this study, accuracy of hepatobiliary scintigraphy (HBS) and impact of hyperbilirubinemia were evaluated. Methods. Between November 2007 and February 2016, 131 patients underwent hepatobiliary scintigraphy after having liver surgery. 39 patients with 42 scans after LTX (n = 13) or hepatic resection (n = 26) were evaluated in the study; 27 were male, with mean age 60 years. The subjects underwent hepatobiliary scintigraphy with Tc-99m labeled Mebrofenin. The results were compared to ERCP as gold standard performed within one month after HBS. We calculated sensitivity, specificity, PPV, and NPV. We compared LTX patients to patients with other liver surgeries. Furthermore the influence of hyperbilirubinemia on HBS scans was evaluated. Results. HBS always provided the correct diagnosis in cases of bile leak in the liver-resected group (14/14). Overall diagnostic accuracy was 76% (19/25) in this group and 54% (7/13) in the LTX group. False negative (FN) diagnoses occurred more often among LTX patients (p = 0.011). Hyperbilirubinemia (>5 mg/dL) significantly influenced the excretion function of the liver, prolonging HBS's time-activity-curve (p = 0.001). Conclusions. Hepatobiliary scintigraphy is a reliable tool to detect biliary complications, but reduced accuracy must be considered after LTX. PMID:27563464

  6. Accuracy of Hepatobiliary Scintigraphy after Liver Transplantation and Liver Resection.

    PubMed

    Eckenschwiller, Manuel; Ackermann, Hanns; Bechstein, Wolf O; Grünwald, Frank

    2016-01-01

    Background and Aims. Biliary complications are the most frequent complications after common liver surgeries. In this study, accuracy of hepatobiliary scintigraphy (HBS) and impact of hyperbilirubinemia were evaluated. Methods. Between November 2007 and February 2016, 131 patients underwent hepatobiliary scintigraphy after having liver surgery. 39 patients with 42 scans after LTX (n = 13) or hepatic resection (n = 26) were evaluated in the study; 27 were male, with mean age 60 years. The subjects underwent hepatobiliary scintigraphy with Tc-99m labeled Mebrofenin. The results were compared to ERCP as gold standard performed within one month after HBS. We calculated sensitivity, specificity, PPV, and NPV. We compared LTX patients to patients with other liver surgeries. Furthermore the influence of hyperbilirubinemia on HBS scans was evaluated. Results. HBS always provided the correct diagnosis in cases of bile leak in the liver-resected group (14/14). Overall diagnostic accuracy was 76% (19/25) in this group and 54% (7/13) in the LTX group. False negative (FN) diagnoses occurred more often among LTX patients (p = 0.011). Hyperbilirubinemia (>5 mg/dL) significantly influenced the excretion function of the liver, prolonging HBS's time-activity-curve (p = 0.001). Conclusions. Hepatobiliary scintigraphy is a reliable tool to detect biliary complications, but reduced accuracy must be considered after LTX. PMID:27563464

  7. Noninvasive external cardiac pacing for thallium-201 scintigraphy

    SciTech Connect

    Feldman, M.D.; Warren, S.E.; Gervino, E.V.; Aroesty, J.M.; Royal, H.D.; Parker, J.A.; Silverman, K.J.; Kolodny, G.M.; Zoll, P.M.; McKay, R.G.

    1988-01-01

    Improvements in noninvasive external cardiac pacing have led to a technique with reliable electrical capture and tolerable patient discomfort. To assess the use of this modality of pacing in combination with thallium scintigraphy as a noninvasive pacing stress test, we applied simultaneous noninvasive cardiac pacing, hemodynamic monitoring, and thallium-201 scintigraphy in 14 patients undergoing cardiac catheterization for chest pain syndromes. Two patients had normal coronary arteries, while the remaining 12 had significant coronary artery disease. Thallium scintigraphic responses to pacing were compared to routine exercise thallium stress testing in nine of these 14 patients. All patients were noninvasively paced to more than 85% of the age-predicted maximum heart rate. Twelve patients demonstrated reversible thallium defects, which corresponded in 11 cases to significant lesions seen on coronary angiography. Of nine patients who underwent both pacing and exercise thallium stress tests, comparable maximal rate-pressure products were achieved. Moreover, thallium imaging at peak pacing and during delayed views did not differ significantly from exercise thallium scintigraphy. A limiting factor associated with the technique was local patient discomfort, which occurred to some degree in all patients. We conclude that noninvasive external cardiac pacing together with thallium scintigraphy is capable of detecting significant coronary artery disease and may be comparable to routine exercise thallium stress testing. This new modality of stress testing could be useful in patients unable to undergo the exercise required for standard exercise tolerance testing, particularly if improvements in the technology can be found to reduce further the local discomfort.

  8. Evaluation of building ventilation systems

    SciTech Connect

    Hughes, R.T.; O'Brien, D.M.

    1986-04-01

    Over the past several years, NIOSH has responded to health hazard evaluation requests from workers in dozens of office environments. Typically, the employees have complained of headache, eye and upper respiratory tract irritation, dizziness, lethargy and the inability to concentrate. Most often inadequate ventilation has been blamed for these complaints. Of paramount importance in the evaluation and correction of these problems is an effective evaluation of the building's ventilation system. Heating, ventilating and air-conditioning conditions that can cause worker stresses include: migration of odors or chemical hazards between building areas; reentrainment of exhaust from building fume hoods or through heat wheels; buildup of microorganisms in the HVAC system components; and poor odor or environmental control due to insufficient fresh outdoor air or system heating or cooling malfunction. The purpose of this paper is to provide an overview of building ventilation systems, the ventilation problems associated with poorly designed or operating systems, and the methodology for effectively evaluating system performance.

  9. Andreas Vesalius' understanding of pulmonary ventilation.

    PubMed

    Hage, J Joris; Brinkman, Romy J

    2016-09-01

    The historical evolution of understanding of the mechanical aspects of respiration is not well recorded. That the anatomist Andreas Vesalius (1515-1564) first recorded many of these mechanics in De Humani Corporis Fabrica Libri Septem has received little attention. We searched a digital copy of De Fabrica (1543) and its English translation as provided by Richardson and Carman (1998-2009) for references to aspects of pulmonary ventilation. We found that Vesalius grasped the essentials of tidal and forced respiration. He recognized that atmospheric pressure carried air into the lungs, approximately 100 years before Borelli did. He described an in vivo experiment of breathing, some 120 years before John Mayow produced his artificial model. He reported on positive pressure ventilation through a tracheotomy and on its life-saving effect, some 100 years before Robert Hook did. In publicly recording his insights over 450 years ago, Vesalius laid a firm basis for our understanding of the physiology of respiration and the management of its disorders. PMID:27238371

  10. Andreas Vesalius' understanding of pulmonary ventilation.

    PubMed

    Hage, J Joris; Brinkman, Romy J

    2016-09-01

    The historical evolution of understanding of the mechanical aspects of respiration is not well recorded. That the anatomist Andreas Vesalius (1515-1564) first recorded many of these mechanics in De Humani Corporis Fabrica Libri Septem has received little attention. We searched a digital copy of De Fabrica (1543) and its English translation as provided by Richardson and Carman (1998-2009) for references to aspects of pulmonary ventilation. We found that Vesalius grasped the essentials of tidal and forced respiration. He recognized that atmospheric pressure carried air into the lungs, approximately 100 years before Borelli did. He described an in vivo experiment of breathing, some 120 years before John Mayow produced his artificial model. He reported on positive pressure ventilation through a tracheotomy and on its life-saving effect, some 100 years before Robert Hook did. In publicly recording his insights over 450 years ago, Vesalius laid a firm basis for our understanding of the physiology of respiration and the management of its disorders.

  11. Physiological dead space and effective parabronchial ventilation in ducks.

    PubMed

    Hastings, R H; Powell, F L

    1986-01-01

    Gas exchange in avian lungs is described by a cross-current model that has several differences from the alevolar model of mammalian gas exchange [e.g., end-expired PCO2 greater than arterial PCO2 (PaCO2)]. Consequently the methods available for estimating effective ventilation and physiological dead space (VDphys) in alveolar lungs are not suitable for an analysis of gas exchange in birds. We tested a method for measuring VDphys in birds that is functionally equivalent to the conventional alveolar VDphys. A cross-current O2-CO2 diagram was used to define the ideal expired point (PEi) and VDphys was calculated as from the equation, VDphys = [(PEiCO2--PECO2)/PEiCO2]. VT, where VT is tidal volume. In seven Pekin ducks VDphys was 13.8 ml greater than anatomic dead space and measured changes in the instrument dead space volume. VDphys also reflected changes in ventilation-perfusion inequality induced by temporary unilateral pulmonary arterial occlusion. Bohr dead space, calculated by substituting end-expired PCO2 for PEiCO2, was insensitive to such inhomogeneity. Enghoff dead space, calculated by substituting PaCO2 for PEiCO2, is theoretically incorrect for cross-current gas exchange and was often less than anatomic dead space. We conclude that VDphys is a useful index of avian gas exchange and propose a standard definition for effective parabronchial ventilation (VP) analogous to alveolar ventilation (i.e., VP = VE--VDphys, where VE is total ventilation).

  12. Lung disease

    MedlinePlus

    ... the lungs to take in oxygen and release carbon dioxide. People with this type of lung disorder often ... the lungs to take up oxygen and release carbon dioxide. These diseases may also affect heart function. An ...

  13. Collapsed Lung

    MedlinePlus

    A collapsed lung happens when air enters the pleural space, the area between the lung and the chest wall. If it is a ... is called pneumothorax. If only part of the lung is affected, it is called atelectasis. Causes of ...

  14. Ventilation/perfusion scan and dead space in pulmonary embolism: are they useful for the diagnosis?

    PubMed

    Giuntini, C

    2001-12-01

    The diagnostic strategy for pulmonary embolism, based on the mismatch of the ventilation/perfusion scan, was developed some 30 years ago on the following assumption: since the disorder involves the pulmonary vessels, it was surmised that in the embolized regions lung alveoli are unperfused or poorly perfused but well ventilated. Hence, it was inferred that this disorder was characterized, unlike parenchymal disease, by ventilation/perfusion mismatch in the affected lung zones and by an obvious increase of wasted ventilation, i.e., dead space. As matter of fact, experimental evidence on the redistribution of ventilation away from the vascular occluded lung had been already obtained in the early 60s of the last century. More recently, the behavior of regional pulmonary ventilation (V(A)) and blood flow (Q) in patients with acute pulmonary embolism (APE) has been studied by applying the multiple inert gas elimination technique (MIGET). It has been shown that the development of lung units with high V(A)/Q ratio (those with relative prevalence of perfusion obstruction) is accompanied by substantial redistribution of ventilation away from these units. Furthermore, radioisotopic techniques, used to visualize the topographic distributions of V(A) and Q in the same patients studied by MIGET, have shown reduced or absent V(A) in the embolized regions. This may occur by different mechanisms in the various stages of APE: bronchoconstriction mediated by local hypocapnia, atelectasis (occasionally hemorrhagic) related to alteration of surfactant production, bronchiolar obstruction and pulmonary infarction ascribed to degenerative and/or necrotic changes secondary to insufficient blood flow. In dogs and humans alike, the dead space measured by MIGET does not increase and that obtained from CO2 increases far less than the amount of unperfused lung in APE thus confirming a substantial redistribution of ventilation away from the embolized lung zones. Taken together, all these

  15. Regional volume changes in canine lungs suspended in air

    NASA Technical Reports Server (NTRS)

    Abbrecht, Peter H.; Kyle, Richard R.; Bryant, Howard J.; Feuerstein, Irwin

    1995-01-01

    The purpose of this study was to determine the effect of the absence of a pleural pressure gradient (simulating the presumed condition found in microgravity) upon regional expansion of the lung. We attempted to produce a uniform pressure over the surface of the lung by suspending excised lungs in air. Such studies should help determine whether or not the absence of a pleural pressure gradient leads to uniform ventilation. A preparation in which there is no pleural pressure gradient should also be useful in studying non-gravitational effects on ventilation distribution.

  16. Extracorporeal carbon dioxide removal to "protect" the lung.

    PubMed

    Stirling, S L; Cordingley, J J; Hunter, D N; Griffiths, M J; Wort, S J; Evans, T W; Finney, S J

    2009-08-01

    The case histories are presented of three adults who had severe hypercapnic acidosis despite mechanical ventilation with what were considered to be injurious tidal volumes and airway pressures. The use of a percutaneously inserted arteriovenous extracorporeal carbon dioxide removal (AV-ECCO(2)R) device facilitated a dramatic reduction in the amount of ventilatory support required, achieving a "lung-protective" level. Two patients survived to hospital discharge. One patient died after it became apparent that her late-stage interstitial lung disease was unresponsive to immunosuppression. AV-ECCO(2)R may be a useful strategy in facilitating lung-protective ventilation.

  17. Four-dimensional optical coherence tomography imaging of total liquid ventilated rats

    NASA Astrophysics Data System (ADS)

    Kirsten, Lars; Schnabel, Christian; Gaertner, Maria; Koch, Edmund

    2013-06-01

    Optical coherence tomography (OCT) can be utilized for the spatially and temporally resolved visualization of alveolar tissue and its dynamics in rodent models, which allows the investigation of lung dynamics on the microscopic scale of single alveoli. The findings could provide experimental input data for numerical simulations of lung tissue mechanics and could support the development of protective ventilation strategies. Real four-dimensional OCT imaging permits the acquisition of several OCT stacks within one single ventilation cycle. Thus, the entire four-dimensional information is directly obtained. Compared to conventional virtual four-dimensional OCT imaging, where the image acquisition is extended over many ventilation cycles and is triggered on pressure levels, real four-dimensional OCT is less vulnerable against motion artifacts and non-reproducible movement of the lung tissue over subsequent ventilation cycles, which widely reduces image artifacts. However, OCT imaging of alveolar tissue is affected by refraction and total internal reflection at air-tissue interfaces. Thus, only the first alveolar layer beneath the pleura is visible. To circumvent this effect, total liquid ventilation can be carried out to match the refractive indices of lung tissue and the breathing medium, which improves the visibility of the alveolar structure, the image quality and the penetration depth and provides the real structure of the alveolar tissue. In this study, a combination of four-dimensional OCT imaging with total liquid ventilation allowed the visualization of the alveolar structure in rat lung tissue benefiting from the improved depth range beneath the pleura and from the high spatial and temporal resolution.

  18. A perfluorochemical loss/restoration (L/R) system for tidal liquid ventilation.

    PubMed

    Libros, R; Philips, C M; Wolfson, M R; Shaffer, T H

    2000-01-01

    Tidal liquid ventilation is the transport of dissolved respiratory gases via volume exchange of perfluorochemical (PFC) liquid to and from the PFC-filled lung. All gas-liquid surface tension is eliminated, increasing compliance and providing lung protection due to lower inflation pressures. Tidal liquid ventilation is achieved by cycling fluid from a reservoir to and from the lung by a ventilator. Current approaches are microprocessor-based with feedback control. During inspiration, warmed oxygenated PFC liquid is pumped from a fluid reservoir/gas exchanger into the lung. PFC fluid is conserved by condensing (60-80% efficiency) vapor in the expired gas. A feedback-control system was developed to automatically replace PFC lost due to condenser inefficiency. This loss/restoration (L/R) system consists of a PFC-vapor thermal detector (+/- 2.5%), pneumatics, amplifiers, a gas flow detector (+/- 1%), a PFC pump (+/- 5%), and a controller. Gravimetric studies of perflubron loss from a flask due to evaporation were compared with experimental L/R results and found to be within +/- 1.4%. In addition, when L/R studies were conducted with a previously reported liquid ventilation system over a four-hour period, the L/R system maintained system perflubron volume to within +/- 1% of prime volume and 11.5% of replacement volume, and the difference between experimental PFC loss and that of the L/R system was 1.8 mL/hr. These studies suggest that the PFC L/R system may have significant economic (appropriate dosing for PFC loss) as well as physiologic (maintenance of PFC inventory in the lungs and liquid ventilator) impact on liquid ventilation procedures.

  19. A perfluorochemical loss/restoration (L/R) system for tidal liquid ventilation.

    PubMed

    Libros, R; Philips, C M; Wolfson, M R; Shaffer, T H

    2000-01-01

    Tidal liquid ventilation is the transport of dissolved respiratory gases via volume exchange of perfluorochemical (PFC) liquid to and from the PFC-filled lung. All gas-liquid surface tension is eliminated, increasing compliance and providing lung protection due to lower inflation pressures. Tidal liquid ventilation is achieved by cycling fluid from a reservoir to and from the lung by a ventilator. Current approaches are microprocessor-based with feedback control. During inspiration, warmed oxygenated PFC liquid is pumped from a fluid reservoir/gas exchanger into the lung. PFC fluid is conserved by condensing (60-80% efficiency) vapor in the expired gas. A feedback-control system was developed to automatically replace PFC lost due to condenser inefficiency. This loss/restoration (L/R) system consists of a PFC-vapor thermal detector (+/- 2.5%), pneumatics, amplifiers, a gas flow detector (+/- 1%), a PFC pump (+/- 5%), and a controller. Gravimetric studies of perflubron loss from a flask due to evaporation were compared with experimental L/R results and found to be within +/- 1.4%. In addition, when L/R studies were conducted with a previously reported liquid ventilation system over a four-hour period, the L/R system maintained system perflubron volume to within +/- 1% of prime volume and 11.5% of replacement volume, and the difference between experimental PFC loss and that of the L/R system was 1.8 mL/hr. These studies suggest that the PFC L/R system may have significant economic (appropriate dosing for PFC loss) as well as physiologic (maintenance of PFC inventory in the lungs and liquid ventilator) impact on liquid ventilation procedures. PMID:11098391

  20. Which patients are candidates for lung transplantation? Indications for unilateral, bilateral, and heart-lung procedures.

    PubMed

    Ettinger, N A

    1994-01-01

    Single-lung transplantation, long successful in resolving interstitial lung disease, can now be used in COPD patients and shows promise in managing pulmonary hypertension. The bilateral procedure, which often avoids cardiopulmonary bypass, is preferred when chronic airway infection is present. Heart-lung transplants, now rare, are used when pulmonary hypertension is complicated by congestive cardiomyopathy or irreparable cardiac defects. Mechanical ventilation, prior cardiothoracic surgery, and corticosteroid use no longer constitute absolute contraindications to lung transplantation. The growing scarcity of donor organs is increasing waiting times; thus, earlier recognition of potential recipients is necessary.

  1. Comparison of CT-derived Ventilation Maps with Deposition Patterns of Inhaled Microspheres in Rats

    SciTech Connect

    Jacob, Rick E.; Lamm, W. J.; Einstein, Daniel R.; Krueger, Melissa; Glenny, Robb W.; Corley, Richard A.

    2015-04-01

    Purpose: Computer models for inhalation toxicology and drug-aerosol delivery studies rely on ventilation pattern inputs for predictions of particle deposition and vapor uptake. However, changes in lung mechanics due to disease can impact airflow dynamics and model results. It has been demonstrated that non-invasive, in vivo, 4DCT imaging (3D imaging at multiple time points in the breathing cycle) can be used to map heterogeneities in ventilation patterns under healthy and disease conditions. The purpose of this study was to validate ventilation patterns measured from CT imaging by exposing the same rats to an aerosol of fluorescent microspheres (FMS) and examining particle deposition patterns using cryomicrotome imaging. Materials and Methods: Six male Sprague-Dawley rats were intratracheally instilled with elastase to a single lobe to induce a heterogeneous disease. After four weeks, rats were imaged over the breathing cycle by CT then immediately exposed to an aerosol of ~1µm FMS for ~5 minutes. After the exposure, the lungs were excised and prepared for cryomicrotome imaging, where a 3D image of FMS deposition was acquired using serial sectioning. Cryomicrotome images were spatially registered to match the live CT images to facilitate direct quantitative comparisons of FMS signal intensity with the CT-based ventilation maps. Results: Comparisons of fractional ventilation in contiguous, non-overlapping, 3D regions between CT-based ventilation maps and FMS images showed strong correlations in fractional ventilation (r=0.888, p<0.0001). Conclusion: We conclude that ventilation maps derived from CT imaging are predictive of the 1µm aerosol deposition used in ventilation-perfusion heterogeneity inhalation studies.

  2. Comparison of CT-derived ventilation maps with deposition patterns of inhaled microspheres in rats

    PubMed Central

    Jacob, Richard E.; Lamm, Wayne J.; Einstein, Daniel R.; Krueger, Melissa A.; Glenny, Robb W.; Corley, Richard A.

    2016-01-01

    Purpose Computer models for inhalation toxicology and drug-aerosol delivery studies rely on ventilation pattern inputs for predictions of particle deposition and vapor uptake. However, changes in lung mechanics due to disease can impact airflow dynamics and model results. It has been demonstrated that non-invasive, in vivo, 4DCT imaging (3D imaging at multiple time points in the breathing cycle) can be used to map heterogeneities in ventilation patterns under healthy and disease conditions. The purpose of this study was to validate ventilation patterns measured from CT imaging by exposing the same rats to an aerosol of fluorescent microspheres (FMS) and examining particle deposition patterns using cryomicrotome imaging. Materials and Methods Six male Sprague-Dawley rats were intratracheally instilled with elastase to a single lobe to induce a heterogeneous disease. After four weeks, rats were imaged over the breathing cycle by CT then immediately exposed to an aerosol of ~1μm FMS for ~5 minutes. After the exposure, the lungs were excised and prepared for cryomicrotome imaging, where a 3D image of FMS deposition was acquired using serial sectioning. Cryomicrotome images were spatially registered to match the live CT images to facilitate direct quantitative comparisons of FMS signal intensity with the CT-based ventilation maps. Results Comparisons of fractional ventilation in contiguous, non-overlapping, 3D regions between CT-based ventilation maps and FMS images showed strong correlations in fractional ventilation (r=0.888, p<0.0001). Conclusion We conclude that ventilation maps derived from CT imaging are predictive of the 1μm aerosol deposition used in ventilation-perfusion heterogeneity inhalation studies. PMID:25513951

  3. Cardiac gated ventilation

    SciTech Connect