Premium
External inspiratory resistance of protective respiratory devices: Effects on physical performance and respiratory function
Author(s) -
Lerman Y.,
Shefer A.,
Epstein Y.,
Keren G.
Publication year - 1983
Publication title -
american journal of industrial medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.7
H-Index - 104
eISSN - 1097-0274
pISSN - 0271-3586
DOI - 10.1002/ajim.4700040606
Subject(s) - medicine , peak inspiratory pressure , respirator , airway resistance , respiratory system , tidal volume , cardiology , anesthesia , composite material , materials science
Twenty subjects wearing protective respirators were studied during submaximal exercise (80% of Vo 2 max) on a treadmill. The protective devices were fitted with canister filters of low expiratory resistance and different inspiratory resistances: (0.3, 1.8, 2.8, 3.4, 3.9, and 4.6 cm H 2 O x sec/liter). The effect of inspiratory resistance on physical endurance, various physiological parameters, and subjective sensations was examined. With the increase in inspiratory resistance, a significant decrease in physical performance, decrease in tidal volume, increased ratio of inspiratory to expiratory time, increased peak inspiratory pressure, and increased CO 2 retention were observed. The difficulty in inspiration correlated significantly to inspiratory resistance and seems to be the main reason for cessation of the effort. No acceptable upper limit for the inspiratory resistance of the canister filters was found. Any decrease in the inspiratory resistance of the mask's filter enhanced endurance and performance.