PRINCIPAL INVESTIGATOR(S ): Charles F. Sawin, Arnauld E. Nicogossian, A. Paul 



Schachter, John A. Rummel, and Edward L. Michel 



EXPERIMENT TITLE/NUMBER : Pulmonary Function Evaluation During and Following 



Skylab Space Flights 



PROGRAM/MISSION : Skylab 2, 3, 4 



CLASSIFICATION : Human 



DISCIPLINE(S) : Respiratory 



OBJECTIVES : To evaluate the effects of space flight on pulmonary function. 



PROTOCOL : Forced vital capacity was measured during the preflight and 

 postf light periods of the Skylab 2 mission. Initial inflight measurements of 

 vital capacity were obtained during the last two weeks of the second manned 

 mission. Comprehensive pulmonary function screening was accomplished during 

 the Skylab 4 mission. The primary measurements made during Skylab 4 testing 

 included residual volume determination, closing volume, vital capacity and 

 forced vital capacity and its derivatives. In addition, comprehensive 

 inflight vital capacity measurements were made during Skylab 4. 



EQUIPMENT : Analog tape recorder, differentiator, strip-chart recorder, 

 digital voltmeter for nitrogen production, respiratory mass specrtometer , 

 Skylab metabolic analyzer, XY plotter. 



RESULTS : Pulmonary function assessment showed no change at R+24h. Parameters 

 measured were: capacities (total lung, residual, vital, forced vital); flow 

 rates (maximum expiratory, maximum midexpiratory , expiratory in 1 s); closing 

 capacity, and closing volume. Inflight vital capacity was slightly reduced. 



CONCLUSIONS : The vital capacity changes observed inflight may be partially 

 explained as a response to 5 psia ambient pressure. However, the proportion 

 of vital capacity decreases directly attributable to other factors such as 

 body bluid shifts and a cephalad shift of the diaphragm cannot be determined 

 from the present data. Regardless of the cause(s) of decreased inflight vital 

 capacities, a review of postf light data shows that these changes revert to 

 normal within two hours following recovery without significant impact on crew 

 health status. 



PUBLICATIONS : 464, 465, 466 



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