Toung T, Saharia P, Permutt S, Zuidema G D, Cameron J L
Surgery. 1977 Aug;82(2):279-83.
With an ex vivo, isolated, ventilated, perfused canine pulmonary lobe, the effects of various levels of positive end-expiratory pressure (PEEP) were evaluated following acid injury. Following intrabronchial instillation of hydrochloric acid, eight lobes were ventilated with 5 cm of H2O of PEEP, 12 lobes with 10 cm of PEEP, and eight lobes with 15 cm of PEEP during a 4 hour perfusion period. Blood flow was kept constant in all preparations. Lobes with 5 cm of PEEP developed a 39% intrapulmonary shunt and increased their weight by 220%. When PEEP was increased to 10 cm, weight gain was similar (184%), but shunting decreased markedly, to 7%. When PEEP was increased further to 15 cm, shunting remained low (13%), but weight gain increased markedly, to 411% of the initial lobe weight. This study demonstrates the beneficial effects of PEEP in aspiration pneumonia, but it also points out that increasing levels of PEEP can magnify acid-pulmonary injury by causing a further increase in interstitial and intralveolar edema.
在离体、分离、通气、灌注的犬肺叶上，评估了酸损伤后不同水平呼气末正压（PEEP）的影响。在支气管内滴注盐酸后，在4小时的灌注期内，8个肺叶以5cmH₂O的PEEP通气，12个肺叶以10cm的PEEP通气，8个肺叶以15cm的PEEP通气。所有标本的血流均保持恒定。采用5cmPEEP的肺叶出现了39%的肺内分流，重量增加了220%。当PEEP增加到10cm时，重量增加相似（184%），但分流明显减少，降至7%。当PEEP进一步增加到15cm时，分流仍较低（13%），但重量增加显著，达到初始肺叶重量的411%。本研究证明了PEEP在吸入性肺炎中的有益作用，但也指出，PEEP水平的增加可通过导致间质和肺泡内水肿的进一步增加而放大酸对肺的损伤。
