单肺通气时非通气侧肺持续中低流量给氧对患者肺组织氧化应激反应的影响

Effect of continuous low- to medium-flow oxygen administration in non-ventilated lung on oxidativestress response of lung tissues during one-lung ventilation

目的评价单肺通气时非通气侧肺持续中低流量给氧对患者肺组织氧化应激反应的影响。 方法择期肺部肿瘤切除术患者57例，年龄50～64岁，性别不限，体重40～74 kg, ASA分级Ⅰ或Ⅱ级。采用随机数字表法分为2组：对照组（C组，n＝29）和持续给氧组（O组，n＝28）。麻醉诱导后行双腔气管导管插管术，采用纤维支气管镜确定双腔气管导管位置。O组单肺通气即刻于非通气侧肺置入F14导管于气管隆突后2～3 cm，持续以1～4 L/min中低流量给氧，氧浓度25%～37%。分别于麻醉诱导即刻（T1）、单肺通气30 min（T2）、1 h（T3）和2 h（T4）时，采集桡动脉和颈内静脉球部血样，进行血气分析。病变组织切除即刻切取肿瘤旁5 cm处肺组织，采用化学比色法测定SOD和MDA水平，采用Western blot法检测血红素氧合酶-1（HO-1）表达。 结果与C组比较，O组T2-4时PaO2升高，T2，3时PaCO2降低，T2，3时PvO2升高，T2-4 时PvCO2降低，肺组织MDA水平降低，HO-1表达上调（P〈0.05），SOD水平差异无统计学意义（P〉0.05）。 结论单肺通气时非通气侧肺持续中低流量给氧对患者产生肺保护作用的机制与抑制肺组织氧化应激反应有关。

Objective To evaluate the effect of continuous low- to medium-flow oxygen administra- tion in non-ventilated lung on the oxidative stress response of lung tissues during one-lung ventilation （OLV）. Methods Fifty-seven American Society of Anesthesiologists physical status I or Ⅱ patients, aged 50-64 yr, weighing 40-74 kg, scheduled for elective pulmonary tumorectomy, were divided into 2 groups using a random number table： control group （group C, n = 29） and continuous oxygen administra- tion group （group O, n = 28）. The patients were intubated with the double-lumen tube after induction of anesthesia. Correct position of the tube was verified with the fiberoptic bronehoscope. In group O, the F14 tube was placed at 2-3 em beyond the earina of trachea in the non-ventilated lung at the beginning of OLV, and low- to medium-flow oxygen was continuously administered at 1-4 L/min with the fractional concentra- tion of inspired oxygen set at 25%-37%. Blood samples were taken from the radial artery and internal jugu- lar bulb at the beginning of anesthesia induction （Ti ） and 30 rain, 1 h and 2 h of OLV （T2_4） for blood gas analysis. Lung tissues at the site 5 em lateral to the tumor were taken immediately after resection of diseased tissues for determination of superoxide dismutase and malondialdehyde levels （by chemical eolorimetry） and heme oxygenase-1 expression （by Western blot）. Results Compared with group C, the partial pressure of arterial oxygen was significantly increased at T2.4, the partial pressure of arterial carbon dioxide was de- creased at T2.3 , the partial pressure of venous oxygen was increased at T2.3 , the partial pressure of venous carbon dioxide was decreased at T2-4 , the malondialdehyde level was decreased, and the expression of hemeoxygenase-1 was up-regulated （P〈0.05）, and no significant change was found in superoxide dismutase lev- el in group O （P〉0. 05）. Conclusion The mechanism by which continuous low- to medium-flow oxygen administration in non-ventilated lung exerts pulmonary protection is related to inhibiting oxidative stress re- sponses of lung tissues during OLV.