Comparison of techniques to measure pulmonary capillary filtration coefficients in dogs
1981; Elsevier BV; Volume: 21; Issue: 2 Linguagem: Inglês
10.1016/0026-2862(81)90026-1
ISSN1095-9319
AutoresRobert E. Drake, Joseph Gabel,
Tópico(s)Cardiac Arrest and Resuscitation
ResumoThe pulmonary capillary filtration coefficient (Kf) was estimated with two different techniques in the same preparation. The lower left lobes of nine halothane-anesthetized dogs were continuously weighed while the perfusion pressures were controlled. In one technique (weight transient technique) we increased the arterial (Pa) and venous (Pv) pressures in previously isogravimetric lobes and estimated the initial rate of capillary filtration from the rate of weight gain. The initial rate of weight gain was then divided by the calculated change in capillary pressure (Pc = (Pa + Pv)2) to calculate Kf. For the second Kf determination, Pa and Pv were increased to edema-producing levels and the rate of weight gain was determined at two or three elevated pressures (constant weight gain technique). Kf was calculated as the change in the rate of weight gain divided by the change in Pc. Although the weight transient Kf (0.047 ± 0.005 g/min · mm Hg) was significantly higher than the continuous weight gain Kf of 0.038 ± 0.004 (P < 0.05, paired data), the two Kf's were close. These data indicate that in experiments performed in this way, these two independent techniques yield similar values of Kf.
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