Lung sounds during allergen-induced asthmatic responses in patients with asthma

Autor: Peter J. Sterk, Zuzana Diamant, J. Vanderschoot, Aeilko H. Zwinderman, Henk J. W. Schreur, Joop H. Dijkman
Přispěvatelé: Other departments
Jazyk: angličtina
Rok vydání: 1996
Předmět:
Zdroj: American journal of respiratory and critical care medicine, 153(5), 1474-1480. American Thoracic Society
ISSN: 1073-449X
Popis: We postulated that the distinct pathophysiologic mechanisms of airway narrowing during the early (EAR) and the late (LAR) asthmatic responses to inhaled allergens are reflected by the generation or transmission of lung sounds in asthma. Therefore, we measured FEV1 and recorded lung sounds in eight mildly asthmatic subjects before a standardized allergen challenge (PRE), during the EAR, during the recovery phase at 2 h (MID), during the LAR at 7 h, and after inhalation of a bronchodilator (POST). The recordings were made during flow- and volume-standardized quiet breathing, and during maximal forced breathing maneuvers. Airflow-dependent power spectra were analyzed for lung sound intensity (LSI), quartile power points (Q25, Q50, Q75), and extent of wheezing (W). These sound characteristics were compared among the various stages of the challenge in the presence (EAR, LAR) and absence (PRE, MID, POST) of acute airway obstruction using ANOVA. LSI, Q25 - Q75, and W were all elevated during airway obstruction. When matched for percent fall in FEV1, during the EAR and the LAR (mean +/- SD: 26.7 +/- 4.0, and 28.9 +/- 5.7, respectively; p = 0.385), the increase in Q25, and Q50 with airflow during quiet expiration, as well as the extent of wheezing, were higher during the LAR than during the EAR (p or = 0.156), LSI on expiration was higher at POST than at PRE or MID (p
Databáze: OpenAIRE