背驮式肝移植围手术期肺氧合及分流的变化

Changes in Pulmonary Gas Exchange and Intrapulmonary Shunt during Piggyback Liver Transplantation

目的探讨背驮式肝移植患者围手术期肺氧合及肺内分流的变化。方法36例背驮式肝移植患者,留置Swan-Gunz导管和右桡动脉插管,于无肝前期、无肝期30min、新肝期30min和手术结束时测量动脉血PaO2,PaCO2和CO。P(A-a)O2,PaO2/FiO2和Qs/Qt根据标准公式计算。术中机械通气吸氧浓度为100%。结果无肝期CO和PaO2/FiO2较无肝前期明显降低(P<0.01),而P(A-a)O2和Qs/Qt明显升高(P<0.01)。在新肝期CO,Qs/Qt和P(A-a)O2较无肝前期明显升高(P<0.05),但PaO2/FiO2仍明显降低(P<0.05)。手术结束时PaO2/FiO2仍明显低于无肝前期(P<0.05),而CO明显增加(P<0.05),但P(A-a)O2示Qs/Qt与无肝前期比较无明显差异(P>0.05)。结论背驮式肝移植患者术中存在明显肺氧合功能改变。

Objective To study the changes in pulmonary gas exchange and intrapulmonary shunt during orthotopic liver transplantation. Methods The right radial arteries were catheterized in 36 patients undergoing piggyback liver transplantation. All the patients were mechanically ventilated with 100% O2 during the operation. Arterial blood sample was taken during the operation , and partial pressure of oxygen（PaO2 ）, and carbon dioxide （PaCO2）, and cardiac output（CO） were determined before anhepatic stage , during 30 minutes anhepatic stage , during 30 minutes neohepatic stage and at the end of operation. Alveolar-arterial oxygen partial pressure difference [-P（A-a）O2], gas exchange index of PaO2/FiO2 and intrapulmonary shunt（Qs/Qt） were calculated according to the standard formula. Results Compared with that before the anhepatic stage, CO and PaO2/FiO2 were significantly decreased during the an.hepatic stage （P〈0. 01 ）, but P（A-a）O2 and Qs/Qt were significantly increased （P〈0. 01）. Compared with that before the anhepatic stage, CO, Qs/Qt and P（A- a） O2 were significantly increased during the neohepatic stage （P〈0. 05）, but PaO2/FiO2 was significantly decreased （P〈 0. 05）. Compared with that before the anhepatic stage, PaO2/FiO2 was significantly decreased （P〈0. 05）, and CO was significantly increased （P〈0. 05）, but there were no significantly difference in P（A-a）O2 and Qs/Qt （P〉0. 05） at the end of the operation. Conclusion There are significant changes in pulmonary gas exchange and intrapulmonary shunt during the piggyback liver transplantation.