Journal of Applied Physiology, Vol 62, Issue 2 477-484, Copyright © 1987 by American Physiological Society
Hemodynamic effects of rapidly evacuating prolonged pneumothorax in rabbits
D. J. Pavlin, M. L. Nessly and F. W. Cheney
Clinical observations suggest that systemic hypotension may be caused by
rapid evacuation of persistent pneumothorax. This observation has not been
substantiated experimentally and the mechanism(s) are unknown. In this
study, we measured systemic hemodynamic parameters in rabbits before and
for 2 h during negative pressure evacuation of a right-sided pneumothorax
of 7-9 days duration. Three groups of animals were studied: 10 rabbits
breathed room air and were hypoxemic during pneumothorax (hypoxemic
pneumothorax = HP); 10 rabbits breathed 40% O2-60% N2, which prevented
arterial hypoxemia during pneumothorax (supraoxemic pneumothorax = SP);
seven normal control animals were untreated during this time period (NC).
Pneumothoraces in HP and SP were evacuated by negative pressure applied to
the right pleural space for 2 h while animals were anesthetized and
mechanically ventilated. The NC group was anesthetized and ventilated
without prior pneumothorax. Serial hemodynamic measurements were made
before and during pleural suction.(ABSTRACT TRUNCATED AT 250 WORDS)
