Kaneko K, Nakayama K, Shimizu K, Yamaguchi O, Usuda Y, Okutsu Y
Department of Anesthesiology, Yokohama City University School of Medicine.
Masui. 1990 Mar;39(3):372-5.
Eight patients, of ASA physical status I or II soon after total knee replacement under general anesthesia, were studied to compare negative extra-thoracic pressure ventilation (NETPV) with positive airway pressure ventilation (PAPV). The measured parameters during the two ventilatory modes were tidal volume, arterial blood gas and functional residual capacity change (delta FRC). Tidal volume obtained during NETPV was 60 to 80% of that during PAPV at the same absolute values of peak pressure. delta FRC obtained during NETPV was 30 to 40% of that during PAPV at the same absolute values of end-expiratory pressure. A decrease in the esophageal pressure was 4 to 11cmH2O at an end-expiratory negative extra-thoracic pressure of -10 to -20 cmH2O. When the patients were ventilated with the same values of minute ventilation on NETPV and PAPV, there was no significant difference in blood gas values. These findings suggest that efficiency of NETPV is less than that of PAPV at the same absolute working pressure but pulmonary gas exchange of NETPV is almost equal to that of PAPV at the same minute ventilation in the normal lung.
选取8例在全身麻醉下行全膝关节置换术后ASA身体状况为I或II级的患者，研究比较胸外负压通气（NETPV）和气道正压通气（PAPV）。两种通气模式下测量的参数为潮气量、动脉血气和功能残气量变化（FRC变化量）。在相同的峰值压力绝对值下，NETPV期间获得的潮气量为PAPV期间的60%至80%。在相同的呼气末压力绝对值下，NETPV期间获得的FRC变化量为PAPV期间的30%至40%。在呼气末胸外负压为-10至-20 cmH₂O时，食管压力降低4至11 cmH₂O。当患者在NETPV和PAPV上以相同的分钟通气量进行通气时，血气值无显著差异。这些发现表明，在相同的绝对工作压力下，NETPV的效率低于PAPV，但在正常肺中，在相同的分钟通气量下，NETPV的肺气体交换几乎与PAPV相等。
