Zeravik J, Borg U, Pfeiffer U J
Institute of Anesthesiology, Zentralkinkum Augsburg, West Germany.
Chest. 1990 Jun;97(6):1412-9. doi: 10.1378/chest.97.6.1412.
Continuous positive-pressure ventilation and PSV were compared prospectively in patients at a surgical intensive care unit. All patients suffered from mild to moderate ARI (PaO2/FIO2 of 125 to 350 mm Hg). The patients were randomly assigned to a PSV group (n = 28) or a control group with continued CPPV (n = 27). The usual hemodynamic and oxygenation variables, ITBV, and extravascular lung water (ETV) were assessed before and six hours after switching to PSV. The changes (d) of PaO2/FIO2, RI, and P(A-a)O2 were used for evaluation of the effect of PSV. Significant correlations were found between the ETV(CPPV) and dPaO2/FIO2 (r = -0.672), ETV(CPPV) and dRI (r = 0.722), and ETV(CPPV) and dP(A-a)O2 (r = 0.601), which led to the conclusion that the level of ETV determined the efficacy of PSV. In the subgroup with ETV less than 11 ml/kg (n = 15), PSV significantly improved PaO2/FIO2 (248 to 286 mm Hg), RI (1.55 to 1.22), ITBV (801 to 888 ml/m2), cardiac index (4.21 to 4.76 L/min.m2), stroke index (42.2 to 48.1 ml/m2), and oxygen delivery (735 to 833 ml/min.m2). In the subgroup with ETV greater than 11 ml/kg (n = 13), PSV caused a significant deterioration of PaO2/FIO2, RI, and intrapulmonary shunt. It is concluded that in patients with moderate ARI in whom ETV is almost normal, PSV is superior to CPPV, and the efficacy of PSV is independent of the level of oxygenation during CPPV.
在一家外科重症监护病房，对连续正压通气（CPPV）和压力支持通气（PSV）进行了前瞻性比较。所有患者均患有轻至中度急性呼吸衰竭（动脉血氧分压/吸入氧分数值[PaO2/FIO2]为125至350 mmHg）。患者被随机分为PSV组（n = 28）或持续CPPV的对照组（n = 27）。在切换至PSV前及切换后6小时，评估常规血流动力学和氧合变量、胸腔内血容量（ITBV）和血管外肺水（EVLW）。采用PaO2/FIO2、呼吸指数（RI）和肺泡-动脉血氧分压差[P(A-a)O2]的变化（d）来评估PSV的效果。发现EVLW（CPPV）与dPaO2/FIO2（r = -0.672）、EVLW（CPPV）与dRI（r = 0.722）以及EVLW（CPPV）与dP(A-a)O2（r = 0.601）之间存在显著相关性，由此得出结论，EVLW水平决定了PSV的疗效。在EVLW小于11 ml/kg的亚组（n = 15）中，PSV显著改善了PaO2/FIO2（从248 mmHg升至286 mmHg）、RI（从1.55降至1.22）、ITBV（从801 ml/m2升至888 ml/m2）、心脏指数（从4.21 L/min·m2升至4.76 L/min·m2）、每搏指数（从42.2 ml/m2升至48.1 ml/m2）和氧输送（从735 ml/min·m2升至833 ml/min·m2）。在EVLW大于11 ml/kg的亚组（n = 13）中，PSV导致PaO2/FIO2、RI和肺内分流显著恶化。得出结论，在中度急性呼吸衰竭且EVLW几乎正常的患者中，PSV优于CPPV，且PSV的疗效与CPPV期间的氧合水平无关。
