Ranieri V M, Eissa N T, Corbeil C, Chassé M, Braidy J, Matar N, Milic-Emili J
Hôpital Saint-Luc, Université de Montréal, Quebec, Canada.
Am Rev Respir Dis. 1991 Sep;144(3 Pt 1):544-51. doi: 10.1164/ajrccm/144.3_Pt_1.544.
The effects of different levels of positive end-expiratory pressure (PEEP) (zero to 15 cm H2O) on the static inflation volume-pressure (V-P) curve of the respiratory system and on gas exchange were studied in eight patients with the adult respiratory distress syndrome (ARDS). Alveolar recruitment with PEEP was quantified in terms of recruited volume, i.e., as difference in lung volume between PEEP and zero end-expiratory pressure (ZEEP) for the same static inflation pressure (20 cm H2O) from the V-P curves obtained at the different PEEP levels. In addition, static compliance of the respiratory system at fixed tidal volume (0.7 L) was determined at the different PEEP levels. The results suggest that: (1) in some patients with ARDS the V-P curves determined on ZEEP exhibit an upward concavity reflecting progressive alveolar recruitment with increasing inflation volume, and PEEP results in alveolar recruitment (range of recruited volume at 15 cm H2O of PEEP: 0.11 to 0.36 L); (2) in other patients with ARDS the V-P curves on ZEEP are characterized by an upward convexity, and PEEP results in a volume displacement along this curve without alveolar recruitment and with enhanced risk of barotrauma; (3) the PEEP-induced increase in arterial oxygenation is significantly correlated to the recruited volume but not to the changes in static compliance. The shape of the static inflation V-P curves on ZEEP allows the prediction of alveolar recruitment with PEEP.
在8例成人呼吸窘迫综合征（ARDS）患者中，研究了不同水平的呼气末正压（PEEP）（0至15 cm H₂O）对呼吸系统静态充气容量-压力（V-P）曲线及气体交换的影响。根据募集容积对PEEP诱导的肺泡复张进行量化，即对于在不同PEEP水平下获得的V-P曲线，在相同的静态充气压力（20 cm H₂O）下，PEEP时与呼气末零压力（ZEEP）时肺容积的差值。此外，在不同PEEP水平下测定固定潮气量（0.7 L）时呼吸系统的静态顺应性。结果表明：（1）在一些ARDS患者中，ZEEP时测定的V-P曲线呈向上凹形，反映随着充气量增加肺泡逐渐复张，PEEP可导致肺泡复张（PEEP为15 cm H₂O时募集容积范围：0.11至0.36 L）；（2）在其他ARDS患者中，ZEEP时的V-P曲线呈向上凸形，PEEP导致沿此曲线的容积移位，无肺泡复张且气压伤风险增加；（3）PEEP引起的动脉氧合增加与募集容积显著相关，但与静态顺应性变化无关。ZEEP时静态充气V-P曲线的形状可预测PEEP引起的肺泡复张。
