异丙酚和安氟醚对单肺通气肺内分流及血浆一氧化氮和内皮素的影响

Effects of propofol and enflurane on intrapulmonary shunt and plasma levels of endothelin and nitric oxide during one lung ventilation

目的 观察异丙酚和安氟醚对单肺通气 (OLV )肺内分流的影响 ,及其肺动、静脉血浆一氧化氮 (NO )和内皮素 (ET )的变化。方法 择期开胸OLV病人 30例 ,随机均分为两组 ,安氟醚组吸入浓度 1 8% ,而异丙酚组微泵输入剂量 6mg·kg-1·h-1。监测双肺通气 (TLV )30min、OLV 30、6 0min时的桡、肺动脉血气及肺动、静脉血浆NO和ET浓度。结果 OLV后 ,两组病人不同时点肺内分流值 (Qs /Qt)均比TLV时显著增加 (P <0 0 1) ,其中安氟醚组较异丙酚组增加更为明显 (P <0 0 5 )。两组肺动、静脉血NO浓度在TLV、OLV期间变化不显著 (P >0 0 5 )。异丙酚组OLV后肺静脉血ET浓度比TLV时上升 (P <0 0 1) ,而安氟醚组其变化不明显 (P >0 0 5 )。结论 临床剂量异丙酚对缺氧性肺血管收缩无明显抑制作用。OLV肺泡缺氧可引起肺内皮细胞分泌ET或肺组织对ET清除作用减弱 ,安氟醚对其有抑制作用。

Objective To observe the effects of propofol and enflurane on intrapulmonary shunt and the changes of plasma endothelin ( ET ) and nitric oxide ( NO ) in the pulmonary artery and vein during one lung ventilation ( OLV ) Methods Thirty patients undergoing elective thoracotomy with OLV were randomly allocated to receiving enflurane at an inspired concentration of 1 8%(enflurane group) or an intravenous infusion of propofol at rate of 6 mg·kg -1 ·h -1 The arterial and mixed venous blood gas analysis and the plasma concentrations of ET and NO in the pulmonary artery and vein were measured 30 min after beginning of two lung ventilation ( TLV ) , 30 min and 60 min after of beginning OLV Results In both groups , the venous admixture percentage(Qs/Qt) increased significantly 30 and 60 min after beginning of OLV compared with that 30 min after beginning of TLV (P<0 01), and was higher in enflurane group than in propofol group (P<0 05) The plasma levels of NO in the pulmonary artery and vein were kept stable in both groups during TLV and OLV (P>0 05) ET concentration in the pulmonary vein increased significantly following OLV in propofol group (P<0 01), whereas remained unchanged in the enflurane group compared with that following TLV (P>0 05) Conclusion Propofol at clinical dosage does not inhibit hypoxic pulmonary vasoconstriction The atelectasis and hypoxic stimulus during OLV can make pulmonary endothelium release ET or inhibit pulmonary elimination of ET Enflurane can suppress the above process