Journal of Applied Physiology, Vol 62, Issue 3 1174-1178, Copyright © 1987 by American Physiological Society
Arterial occlusion versus isofiltration pulmonary capillary pressures during very high flow
Z. Bshouty, J. Ali and M. Younes
Pressure in the compliant middle segment of the pulmonary vascular bed
(PM), as determined by arterial occlusion, was compared with pressure at
the filtration site (effective filtration pressure, EFP), determined by the
isofiltration technique, at very high (7-10 times normal) pulmonary flow in
six in situ perfused canine left upper lobes. At these flow rates inflow
and left atrial pressures averaged 41.9 +/- 1.3 and 2.5 +/- 0.5 (SE) mmHg,
respectively. PM was 30.9 +/- 1.6 mmHg, and EFP was 32.3 +/- 1.9 mmHg with
no significant difference between the two measurements by paired t test.
The results indicate that the arterial occlusion technique yields a
pressure that is equivalent to EFP even during very high pulmonary blood
flow where the longitudinal distribution of resistance is quite different
from that obtained during normal flow.
