Chest
Clinical InvestigationsPulmonary FunctionDetection of Wheezing During Maximal Forced Exhalation in Patients With Obstructed Airways
Section snippets
Materials and Methods
Sixteen nonsmoking patients (9 men and 7 women; mean [SD] age, 53.6 [16.3] years) with persistent but clinically stable moderate-to-severe asthma6 (at least 1 month without an acute attack) for the ≥ 15 years, and 6 patients with COPD (6 men; age, 58.8 [4.9] years) were enrolled. All were ex-smokers from our hospital-based outpatient clinic. Fifteen healthy nonsmoking subjects (7 men and 8 women; age, 46.0 [12.5] years) made up the control group. None had any other disease. The patients were
Results
Table 1shows the anthropometric and spirometric parameters for the 16 patients with asthma, 6 patients with COPD, and 15 control subjects. The control subjects were younger than the patients, but the differences were not significant. The asthma patients and COPD patients had moderate-to-severe obstruction (FEV1 of 40 to 53% predicted).11
Figure 1is the time-frequency spectrogram of a patient with asthma, showing activity lines consistent with wheezes over time. An airflow level between 1.2 L/s
Discussion
The main finding of this study was that more wheezes were detected in patients with airway obstruction than in control subjects during forced exhalation maneuvers. Moreover, the change in the absolute number of wheezes after bronchodilator administration was greater in patients with obstructed airways.
The system we developed records wheezes generated throughout the bronchial tree and is based on principles of sound wave propagation. Intraluminal airway lesions and airway wall thickening in
ACKNOWLEDGMENT
We thank Mary Ellen Kerans and Gary Shivel for language revision, and Sandra Alonso for secretarial assistance.
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2019, Computers in Biology and MedicineCitation Excerpt :Previous studies [8,9,16,17,10] have analysed all samples without discriminating their location or phase. Some researchers [7,15,21] focused only on the expiratory phase, whereas other studies [13,38,39] analysed only the inspiratory phase. Another study [40] obtained data from multiple locations and investigated them separately and/or in combination.
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2018, Respiratory MedicineCitation Excerpt :Previous studies conducted during an AECOPD have shown an improvement in air-flow limitation (assessed by FEV1 and peak expiratory flow - PEF) approximately 15-days post exacerbation [7,19]. Knowing that %Wh is highly associated with the degree of bronchial obstruction [38,39], this was an expected result and enhances the role of wheezes auscultation to monitor AECOPD. Crackles are more related to changes (i.e., inflammation and/or infection) in more peripheral airways which usually take longer to resolve [40,41].
This work was supported in part by a grant from the Spanish Society of Pneumology and Thoracic Surgery in 1999.