Pulmonary function in normal subjects and patients with sarcoidosis after bronchoalveolar lavage

To determine if fiberoptic bronchoscopy (FOB) with bronchoalveolar lavage impairs pulmonary function in normal subjects or those with sarcoidosis, we measured flow-volume loops, thoracic gas volume, and single breath carbon monoxide diffusing capacity before, one half hour and 24 hours after lavage. We studied 12 normal subjects; six underwent a large volume lavage (approximately 500 ml saline instilled), and six underwent a small volume lavage (approximately 175 ml). Five subjects with sarcoidosis also had a small volume lavage. Six control subjects underwent FOB without lavage. The FOB alone produced no significant changes in pulmonary function one half hour after the procedure. Small volume lavage in normal subjects produced no change except for a 16.3 +/- 5.1 percent (mean- +/- SEM) decline in peak expiratory flow rate (p less than .05) one half hour postlavage which returned to normal by 24 hours. This contrasts with sarcoidosis subjects in whom forced expiratory volume in one second, peak expiratory flow rate, and vital capacity declined by 20 +/- 4.8 percent, 26.7 +/- 7.3 percent, and 15.2 +/- 4.1 percent, respectively, (all p less than 0.05) one half hour postlavage. No change occurred in total lung capacity or diffusing capacity. Only with large volume lavage did decrements in lung function occur in normal patients that were comparable to those seen in the sarcoidosis subjects. Our findings suggest that bronchoalveolar lavage in normal patients can be associated with a significant and volume-related decline in pulmonary function and that in subjects with sarcoidosis, the deterioration is more pronounced.