Static end-expiratory and dynamic forced expiratory tracheal collapse in COPD

Abstract

AIM: To determine the range of tracheal collapse at end-expiration among chronic obstructive pulmonary disease (COPD) patients and to compare the extent of tracheal collapse between static end-expiratory and dynamic forced-expiratory multidetector-row computed tomography (MDCT). MATERIALS AND METHODS: After institutional review board approval and obtaining informed consent, 67 patients meeting the National Heart, Lung, and Blood Institute (NHLBI)/World Health Organization (WHO) Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria for COPD were sequentially imaged using a 64-detector-row CT machine at end-inspiration, during forced expiration, and at end-expiration. Standardized respiratory coaching and spirometric monitoring were employed. Mean percentage tracheal collapse at end-expiration and forced expiration were compared using correlation analysis, and the power of end-expiratory cross-sectional area to predict excessive forced-expiratory tracheal collapse was computed following construction of receiver operating characteristic (ROC) curves. RESULTS: Mean percentage expiratory collapse among COPD patients was 17±18% at end-expiration compared to 62±16% during forced expiration. Over the observed range of end-expiratory tracheal collapse (approximately 10–50%), the positive predictive value of end-expiratory collapse to predict excessive (≥80%) forced expiratory tracheal collapse was <0.3. CONCLUSION: COPD patients demonstrate a wide range of end-expiratory tracheal collapse. The magnitude of static end-expiratory tracheal collapse does not predict excessive dynamic expiratory tracheal collapse.

An optimized non-destructive protocol for testing mechanical properties in decellularized rabbit trachea

“…Another remark is the static nature of our set-up. O'Donnell et al concluded that the magnitude of static end-expiratory tracheal collapse does not predict excessive dynamic expiratory tracheal collapse in COPD patients [33]. Further research should elucidate whether dynamic measurements would support our results.…”

Association Between Expiratory Central Airway Collapse and Respiratory Outcomes Among Smokers

“…37–39 However, we used a stringent 50% cutoff for CSA reduction despite scan acquisition with tidal exhalation, and thus detected the more severe cases. Recent studies have shown that with dynamic scans, even normal volunteers can have significant airway collapse, 38,39 and our measurements at tidal exhalation might be clinically more meaningful. Second, COPDGene includes smokers with an oversampling of participants with COPD.…”

Computed tomographic and radiographic bronchial collapse may be a normal characteristic of forced expiration in dogs

“…To date, there have been few veterinary reports about changes in bronchial diameter related to respiratory phase, and bronchial diameters have only been measured at end inspiration or end expiration . In addition, there is no published report on the measurement of bronchial collapsibility during forced expiration in dogs, although bronchial collapsibility during dynamic expiration and end expiration have been actively studied in humans . This lack of related studies could cause misinterpretation of normal variation in the lower airways throughout respiration and the subsequent inaccurate diagnosis of bronchomalacia especially in dogs not undergoing bronchoscopy.…”