Rayman R, Girotti M, Armstrong K, Inman K J, Lee R, Girvan D
Department of Surgery, Victoria Hospital, University of Western Ontario, London, Canada.
Surg Laparosc Endosc. 1995 Dec;5(6):437-43.
We studied deviations from normal physiology in piglets (n = 10; average weight 5.75 kg) during carbon dioxide (CO2) pneumoperitoneum. Cardiopulmonary data were gathered during varying intraabdominal pressures (IAP = 8, 12, 15, 20 mm Hg), each sustained for 10 mins. Each animal was its own preinsufflation and exsufflation control. A rapid, significant rise in arterial CO2 pressure from preinsufflation (46.5 +/- 6.7 mm Hg) to insufflation at 20 mm Hg (72.9 +/- 15 mm Hg; p < 0.05) initiated further cardiac adjustments. Responses included a sustained increase in cardiac index (presufflation = 3.1 +/- 1.4; 20 mm Hg IAP = 3.6 +/- 1.2), increased heart rate (preinsufflation = 121 +/- 21; 20 mm Hg IAP = 150 +/- 28; p < 0.05), and left ventricular stroke work (20 mm IAP = 22.7 +/- 8.9; exsufflation 20 min = 15.3 +/- 9.4 g.m/m2; p < 0.05). There was a significant arterial-end CO2 tidal difference throughout insufflation, as great as 15 mm Hg (p < 0.05), suggesting increasing ventilation dead space. Core temperature decreased significantly from preinsufflation (35.3 +/- 1.3 degrees C) to 20 mm Hg IAP (33.6 +/- 1.5 degrees C, p < 0.05). We suggest the following guidelines based on the above data: (a) preoperative examination screening for cardiopulmonary abnormalities; (b) fluid replacement to normal hydration only; (c) cuffed endotracheal tubes for effective ventilation; (d) careful adjustment of minute ventilation to achieve normocapnia; (e) CO2 warming; (f) maximal insufflation pressure of 12 mm Hg; (g) postoperative care emphasizing respiratory and thermoregulation status.
我们研究了仔猪（n = 10；平均体重5.75千克）在二氧化碳（CO₂）气腹过程中偏离正常生理状态的情况。在不同的腹内压（IAP = 8、12、15、20毫米汞柱）下收集心肺数据，每种腹内压持续10分钟。每只动物自身作为充气前和排气后的对照。动脉血二氧化碳压力从充气前（46.5±6.7毫米汞柱）迅速显著升高至20毫米汞柱充气时（72.9±15毫米汞柱；p < 0.05），引发了进一步的心脏调节。反应包括心脏指数持续增加（充气前 = 3.1±1.4；20毫米汞柱IAP = 3.6±1.2）、心率增加（充气前 = 121±21；20毫米汞柱IAP = 150±28；p < 0.05）以及左心室搏功（20毫米汞柱IAP = 22.7±8.9；排气20分钟后 = 15.3±9.4克·米/平方米；p < 0.05）。在整个充气过程中，动脉端与呼出端的二氧化碳潮气量差异显著，高达15毫米汞柱（p < 0.05），提示通气死腔增加。核心温度从充气前（35.3±1.3摄氏度）显著下降至20毫米汞柱IAP时（33.6±1.5摄氏度，p < 0.05）。基于上述数据，我们提出以下指导原则：（a）术前检查筛查心肺异常；（b）仅补充液体至正常水合状态；（c）使用带套囊的气管内导管以实现有效通气；（d）仔细调整分钟通气量以实现正常碳酸血症；（e）二氧化碳加温；（f）最大充气压力为12毫米汞柱；（g）术后护理着重于呼吸和体温调节状态。
