呼气终末正压通气对麻醉中和术后肺血分流的影响

研究呼气末正压（ＰＥＥＰ）通气对全麻中及术后肺分流（Ｑｓ／Ｑｔ）的影响。选择２０例无心肺疾患行胆囊切除术患者，随机分为实验组（Ｐ组）和对照组（Ｚ组），在全麻诱导后分别行ＰＥＥＰ和呼气终末平压（ＺＥＥＰ）机械通气。并在麻醉前、麻醉后３０分钟、麻醉后１．５小时、麻醉后２．５小时和术后１小时取动脉和右心室混合静脉血行血气分析并计算分流量。结果表明，全麻期间 Ｐ组Ｑｓ／Ｑｔ逐渐减少，术后 １小时恢复至术前水平。 Ｚ组在麻醉中Ｑｓ／Ｑｔ持续升高，术后１小时仍显著高于术前。两组间各不同时期Ｑｓ／Ｑｔ有显著性差异（Ｐ＜０．０５）。结论：全麻可导致肺分流增加，并可持续至术后。全麻后即应用 ＰＥＥＰ通气可减少肺分流，对术后低氧血症和肺部并发症的发生起到预防作用，为患者呼吸功能恢复创造良好条件。

Effects of positive end-expiratory pressure on pulmonary shunt during geneal anesthesia and after the operation

The effects of positive end-expiratory pressure (PEEP) on pulmonary shunt were studied during gen- eral anesthesia and postoperative period.Twenty cholecystectomy patients were randomly divided into experiment group (group P) and control group (group Z). PEEP and ZEEP were used separately after induction. Artery blood and mixed blood from the right ventricle were taken for blood gas analysis and determine the amount of pulmonary shunting before anesthesia. half and hour, one and half an hour and two and half an hour after anesthesia and one hour after the operation.The results showed that shunt in group P decreased gradually during general anesthesia and returned to the level of preoperation at an hour after operation. Shunt in group Z was increased continually and the level was significantly higher than preoperation an hour after operation. Shunt between two groups was significant difference (P<0.05) at different period.It is concluded that general anesthesia may cause the increase of pulmonary shunt and may proceed on to the postopertive period. Using PEEP imme diately after induction may decrease pulmonary shunt, prevent the hypoxia and pulmonary complications after the operation with better respiratory function during recovery.