Huchon G J, Lipavsky A, Hoeffel J M, Murray J F
J Appl Physiol (1985). 1986 Sep;61(3):1132-8. doi: 10.1152/jappl.1986.61.3.1132.
To determine the accuracy of measurements of lung tissue volume (Vlt) by rebreathing acetylene in normal and edematous lungs, we compared gravimetric values of total lung weight (Ql) and extravascular lung water (Qwl) with Vlt in anesthetized control sheep (C) and sheep with hydrostatic pulmonary edema (HPE) or oleic acid-induced permeability pulmonary edema (PPE), five animals each. In eight additional sheep we determined that acetylene solubility in blood (0.117 +/- 0.010 ml X 100 ml-1 X Torr-1) differed significantly from that in lung-blood homogenates (0.095 +/- 0.009 ml X 100 ml-1 X Torr-1, P = 0.0017). The latter value was used in all calculations. In C, Vlt was 194% of Qwl and 98% of Ql; in HPE, Vlt was 144% of Qwl and 87% of Ql; and in PPE, Vlt was 112% of Qwl and 77% of Ql. We conclude that when the lungs are normal, Vlt reasonably measures Ql not Qwl. However in both HPE and PPE, Vlt progressively underestimates Ql and cannot differentiate between increased blood volume and increased Qwl.
为了确定在正常肺和水肿肺中通过重呼吸乙炔测量肺组织体积(Vlt)的准确性,我们比较了麻醉的对照绵羊(C)以及患有静水压力性肺水肿(HPE)或油酸诱导的通透性肺水肿(PPE)的绵羊(每组五只动物)的肺总重量(Ql)和血管外肺水(Qwl)的重量法测量值与Vlt。在另外八只绵羊中,我们确定乙炔在血液中的溶解度(0.117±0.010 ml×100 ml⁻¹×Torr⁻¹)与在肺-血匀浆中的溶解度(0.095±0.009 ml×100 ml⁻¹×Torr⁻¹,P = 0.0017)有显著差异。所有计算均使用后一个值。在C组中,Vlt是Qwl的194%,是Ql的98%;在HPE组中,Vlt是Qwl的144%,是Ql的87%;在PPE组中,Vlt是Qwl的112%,是Ql的77%。我们得出结论,当肺正常时,Vlt能够合理地测量Ql而非Qwl。然而,在HPE和PPE中,Vlt逐渐低估Ql,并且无法区分血容量增加和Qwl增加。