Drummond G B, Martin L V
Br J Anaesth. 1978 Mar;50(3):261-70. doi: 10.1093/bja/50.3.261.
Pressure-volume relationships for the total respiratory system and for the lung were recorded in anaesthetized and paralysed patients, during deflation from an airway pressure of 3 kPa to FRC at a rate of 2 litre min-1. Pleural pressure was estimated by means of an oesophageal balloon. A group of nine female patients (mean age 32.7 yr) about to undergo laparoscopy were each studied in four successive states: supine, 15 degrees head down tilt, tilt and lithotomy position, and again in this position after abdominal inflation with nitrous oxide to a pressure of 0.8(-1) kPa. Compliance values were calculated from the curves. Mean total compliance was increased significantly by moving to the lithotomy position, and reduced markedly after inflation of the abdomen, because of a large reduction in thoracic compliance. Mean lung compliance was unaltered, except for a slight but statistically significant increase on moving from the supine to the Trendelenburg position. Measurement of FRC by helium dilution in a group of seven patients showed that abdominal inflation caused a mean decrease of 19%. Airway closure manoeuvres were carried out using a helium bolus technique from FRC in five patients, but closing volume could be measured in only one patient, in the supine position. The absence of an inflexion in the slope of the pressure-volume curves for the other patients supported this negative finding.
在麻醉和麻痹的患者中，以2升/分钟的速率从3 kPa气道压力放气至功能残气量（FRC）期间，记录了整个呼吸系统和肺的压力-容积关系。通过食管气囊估计胸膜压力。一组即将接受腹腔镜检查的9名女性患者（平均年龄32.7岁），分别在四个连续状态下进行研究：仰卧位、头低15度倾斜位、倾斜和截石位，以及在腹部用一氧化二氮充气至0.8（-1）kPa压力后再次处于该位置。根据曲线计算顺应性值。由于胸廓顺应性大幅降低，转为截石位时平均总顺应性显著增加，腹部充气后则明显降低。平均肺顺应性未改变，但从仰卧位转为头低脚高位时略有增加且具有统计学意义。对一组7名患者用氦稀释法测量功能残气量显示，腹部充气导致平均减少19%。对5名患者从功能残气量开始采用氦弹丸技术进行气道闭合操作，但仅在一名仰卧位患者中测得闭合气量。其他患者压力-容积曲线斜率无拐点支持了这一阴性结果。
