颈部内镜手术充CO2和氦气对代谢和血流动力学的影响

目的：通过兔颈部灌注CO2和氦气（He），检测不同压力和灌注持续时间对动物代谢、血流动力学各项指标的影响。方法：将15只新西兰兔随机分成5组，每组3只，分别为5mmHg（1mmHg=0．133kPa）COz组、10mmHg CO2组、15mmHg CO2组、15mmHg He组及对照组（颈部不充气）。分别在充气前（T0），充气后45min（T1）、90min（T2）和放气后30min（T3）记录PaCO2、pH、HR、MAP和CVP。结果：5mmHg CO2组各项检测指标均无明显变化；10mmHg CO2组在T1和T2时PaCO2显著升高（P〈0．01）；15mmHg CO2组在T1和T2时Pa CO2、PH和CVP显著升高（均P〈0．01），T3时仍高于T0（P〈0．01或P〈0.05）。15mmHg He组在T2时CVP显著升高（P〈0．05），T3时回落到基线水平。各组的HR和MAP在各时间点均无显著变化。结论：在颈部内镜手术中将CO2充气压力控制在10mmHg以下是安全的；当需要更大压力时，应尽可能将压力控制在15mmHg以下，并严格限制充气时间；He由于溶解度低应慎用。

The effect of cervical gas insufflation on metabolic and hemodynamic during endoscopic neck surgery

Objective:Carbon dioxide and helium were insufflated into the neck of rabbits to investigate the effect of different levels of insufflation pressure and duration on metabolic and hemodynamic changes.Method:Fifteen New Zealand rabbits were randomly divided into 5 groups: 5 mmHg CO_2, 10 mmHg CO_2, 15 mmHg CO_2, 15 mmHg He and 0 mmHg. Arterial partial pressure of CO_2 (PaCO_2), pH, heart rate (HR), mean arterial pressure (MAP) and central venous pressure (CVP) were measured at baseline, 45 min and 90 min after gas insufflation and 30 min after desufflation.Result:Insufflation of CO_2 at 5 mmHg had not any significant effect on the parameters. PaCO_2 increased significantly 45 min and 90 min after CO_2 insufflation at 10 mmHg (P<0.05). Marked changes in PaCO_2, pH and CVP occurred 45 min and 90 min after CO_2 insufflation at 15 mmHg (P< 0.05), and the parameters did not return to baseline 30 min after desufflation. In animals receiving He insufflation at 15 mmHg, CVP increased significantly after 90 min(P<0.05), and the parameters returned to baseline 30 min after desufflation. Animals receiving He insufflation did not experience hypercapnia. No significant changes in HR and MAP occurred in all animals.Conclusion:Carbon dioxide insufflation for endoscopic neck surgery is safe below 10 mmHg. When higher pressure is required, the level lower than 15 mmHg is recommended and the insufflation duration should be limited. The use of He should be careful due to the low solubility.