病态肥胖患者腔镜胃旁路手术麻醉中Pet-CO2和PaCO2的相关性

目的观察病态肥胖患者腔镜胃旁路手术麻醉中动脉血二氧化碳分压（PaCO2）与呼吸末二氧化碳分压（Pet-CO2）的关系。
方法观察40 例BMI为35~50 kg/m2，在腔镜下行胃旁路手术的病态肥胖患者，记录在全麻插管后气腹前、气腹30 min，气腹
60 min，气腹120 min，放气后30 min，放气后60 min等不同时间点PaCO2和Pet-CO2的值，比较PaCO2和Pet-CO2的值及其相关
性。结果各时间点的Pet-CO2值均低于PaCO2值，在气腹前、气腹时和气腹放气后3种不同的机体状态下PaCO2和Pet-CO2呈密
切正相关（P<0.05），在16 mmHg中等压力CO2气腹状态下，气腹后30、60、120 min 3个时间点PaCO2和Pet-CO2的相关性与气腹
前、气腹放气后PaCO2和Pet-CO2的相关性的r值有差别。
结论病态肥胖患者在中等CO2气腹压，腹腔镜辅助行胃旁路手术中PaCO2和Pet-CO2是密切相关的。

Correlation between Pet-CO2 and PaCO2 in morbidly obese patients during anesthesia forlaparoscopic gastric bypass surgery

Objective To investigate the correlation between arterial partial pressure of CO2 (PaCO2) and end expiratory tidal
partial pressure of CO2 (Pet-CO2) in morbidly obese patients during anesthesia for laparoscopic gastric bypass surgery.
Methods Forty morbidly obese patients with a body mass index (BMI) between 35 and 50 kg/m2 underwent laparoscopic
gastric bypass surgery under general anesthesia. PaCO2 and Pet-CO2 were measured after intubation and before induction of
pneumoperitoneum (T0), at 30 min (T1), 60 min (T2), and 120 min (T3) during pneumoperitoneum, and at 30 min (T4) and 60 min
(T5) after deflation. Results At each time point of measurement, Pet-CO2 was lower than PaCO2 in all the patients. PaCO2 and
Pet-CO2 were positively correlated before, during, and after pneumoperitoneum (P<0.05). At a moderate pressure of CO2
pneumoperitoneum (16 mmHg), the level of correlation between PaCO2 and Pet-CO2 at T1, T2, and T3 differed from that before
and after post-pneumoperitoneum. Conclusion PaCO2 and Pet-CO2 are closely correlated during a moderate CO2
pneumoperitoneum in morbidly obese patients undergoing laparoscopic gastric bypass surgery.