Winn R, Stothert J, Nadir B, Hildebrandt J
J Appl Physiol Respir Environ Exerc Physiol. 1983 Oct;55(4):1051-6. doi: 10.1152/jappl.1983.55.4.1051.
Pressure-volume curves were obtained from excised left lungs of goats at 4, 24, and 48 h after tracheal instillation of 2.5 ml/kg of 0.1 N HCl. Air total lung capacity (TLC) at transpulmonary pressure (PL) = 35 cmH2O was 38.8 ml/kg body weight before acid, and was reduced sharply to 21.1 at 4 h, then increased to 25.6 at 24 h and 32.1 at 48 h. Excess extravascular lung water (EVLW) could account for only part of the volume reductions. Specific compliance ratio of transpulmonary pressure to total lung capacity (CL/TLC) between PL of 5 and 0 cmH2O was reduced from 0.074/cmH2O to 0.050, 0.048, and 0.053/cmH2O, respectively. Saline TLC (PL = 10 cmH2O) changed from 44.8 to 32.4, 34.3, and 45.4 ml/kg, respectively, but CL/TLC did not, suggesting airway obstruction. After injury, trapped volume at PL = 0 increased from 24.9 to 29.2, 43.3, and 37.3% TLC with air, and from 20.3 to 38.5, 33.1, and 28.5%, respectively, with saline. Air volume at a PL = 10 cmH2O on deflation fell from 82.0 to 72.1% TLC at 4 h, but was near control at 24 and 48 h. The reduction in ventilated volume was not reflected in proportionately increased shunt; therefore, some compensatory vasoconstriction must have occurred. We suggest that in affected regions increased surface forces, increased EVLW, and airway obstruction caused reductions of lung volume.
在向山羊气管内滴注2.5 ml/kg的0.1 N盐酸后的4小时、24小时和48小时，从切除的左肺获取压力-容积曲线。在跨肺压（PL）= 35 cmH₂O时，酸注入前的肺总量（TLC）为38.8 ml/kg体重，在4小时时急剧降至21.1，然后在24小时时增至25.6，在48小时时增至32.1。血管外肺水（EVLW）过多仅能解释部分容积减少。在PL为5至0 cmH₂O之间，跨肺压与肺总量的比顺应性（CL/TLC）分别从0.074/cmH₂O降至0.050、0.048和0.053/cmH₂O。盐水肺总量（PL = 10 cmH₂O）分别从44.8变为32.4、34.3和45.4 ml/kg，但CL/TLC未变，提示气道阻塞。损伤后，在PL = 0时的潴留容积，用空气时从24.9% TLC增加至29.2%、43.3%和37.3% TLC，用盐水时分别从20.3%增加至38.5%、33.1%和28.5%。在PL = 10 cmH₂O时放气时的空气容积在4小时时从82.0% TLC降至72.1% TLC，但在24小时和48小时时接近对照值。通气容积的减少并未按比例反映在分流的相应增加上；因此，必定发生了一些代偿性血管收缩。我们认为，在受影响区域，表面力增加、EVLW增加和气道阻塞导致了肺容积减少。
