肺保护性通气策略对食管癌根治术老年患者单肺通气期间脑氧饱和度的影响

Effect of lung protective ventilation regimen on regional cerebral oxygen saturation during one-lung ventilation in elderly patients undergoing radical esophagus cancer resection

目的评价肺保护性通气策略对食管癌根治术老年患者单肺通气期间脑氧饱和度（rSO2）的影响。方法择期行食管癌根治术的患者40例，年龄65～76岁，体重45～75kg，ASA分级，Ⅰ～Ⅲ级，采用随机数字表法，将其随机分为2组（n=20）：常规通气组（CV组）和保护性通气组（PV组）。静脉注射咪达唑仑0．05mg／kg、舒芬太尼0．4μg／kg、罗库溴铵1mg／kg和异丙酚1．5mg／kg麻醉诱导，左侧插入左侧双腔支气管导管进行机械通气。CV组双肺通气和单肺通气期间v，均为10ml／kg，吸呼比均为1：2；PV组双肺通气和单肺通气期间v，均为6ml／kg，吸呼比均为1：2，并给予PEEP5cmH2O；两组维持PETCO235～45mmHg。吸入2％七氟醚，间断静脉注射罗库溴铵0．5mg／kg维持麻醉。于麻醉诱导前、双肺通气10min和单肺通气30min时，进行动脉血气分析，计算肺内分流率（Qs／Qt），记录rSO2。记录单肺通气期间低rSO2（rSO2积分〉3000％）的发生情况。结果与CV组比较，PV组单肺通气30min时PaO2和rSO2升高，Qs／Qt降低，低rSO2发生率降低（P〈0．05）。结论肺保护性通气策略可改善食管癌根治术老年患者单肺通气期间的氧合，降低肺内分流，减少低rSO2的发生。

Objective To investigate the effect of lung protective ventilation regimen on regional cerebral oxygen saturation （rS02） during one-lung ventilation （OLV） in elderly patients undergoing radical esophagus cancer resection. Methods Forty ASA Ⅰ - Ⅲ patients, aged 65-76 yr, weighing 45-75 kg, undergoing radical esoph- agus cancer resection, were randomly divided into 2 groups （ n = 20 each） ： conventional ventilation group （group CV） and protective ventilation regimen group （group PV）. Anesthesia was induced with midazolam 0.05 mg/kg, sufentanil 0.4 μg/kg, rocuronium 1 mg/kg and propofol 1.5 mg/kg and maintained with 2% sevoflurane and intermittent iv boluses of roeuronium 0.5 mg/kg. Double lumen tube was inserted. Correct positioning was verified by fiberoptie bronehoseopy. The patients were mechanically ventilated. In group CV, PEEP was set at 0, VT was set at 10 ml/kg, and I：E was set at 1：2 during two-lung ventilation （TLV） and OLV. In group PV, PEEP was set at 5 cm H2O, VT was set at 6 ml/kg, and I：E was set at 1：2 during TLV and OLV. PETCO2 was maintained at 35- 40 mm Hg in both groups. Arterial blood samples were taken before induction of anesthesia, at 10 min of TLV and at 30 min of OLV for blood gas analysis. Qs/Qt was calculated and rS02 was recorded at the same time. Low rSO2 （rSO2 score 〉 3000 % ） was recorded during OLV. Results Compared with group CV, PaO2 and rSO2 were significantly increased, and Qs/Qt was significantly decreased at 30 min of OLV, and the incidence of low rSO2 was significantly decreased in group PV （P 〈 0.05）. Conclusion Lung protective ventilation regimen can improve oxygenation, decrease intrapulmonary shunt, and reduce the occurrence of low rSO2 during OLV in elderly patients un- dergoing radical esophagus cancer resection.