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Oral Positive Expiratory Pressure Device for Excessive Dynamic Airway Collapse Caused by Emphysema
Muhammad Ahsan Zafar1, Ruchira Sengupta1, Alister Bates2
1Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Cincinnati College of Medicine, Cincinnati, OH.
Abstract:
Excessive dynamic airway collapse (EDAC) contributes to breathlessness and reduced quality of life in individuals with emphysema. We tested a novel, portable, oral positive expiratory pressure (o-PEP) device in a patient with emphysema and EDAC. MRI revealed expiratory tracheal narrowing to 80 mm2 that increased to 170 mm2 with the o-PEP device. After 2-weeks use of the o-PEP device for 33% to 66% of activities, breathlessness, quality of life, and exertional dyspnea improved compared with minimal clinically important differences (MCID): University of California-San Diego Shortness of Breath questionnaire score declined 69 to 42 (MCID, ≥5), St. George's Respiratory Questionnaire score decreased 71 to 27 (MCID, ≥4), and before and after the 6-minute walk test Borg score difference improved from Δ3 to Δ2 (MCID, ≥1). During the 6-minute walk test on room air without the use of the o-PEP device, oxyhemoglobin saturation declined 91% to 83%; whereas, with the o-PEP device, the nadir was 90%. Use of the o-PEP device reduced expiratory central airway collapse and improved dyspnea, quality of life, and exertional desaturation in a patient with EDAC and emphysema.
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