单肺通气不同水平呼气末正压对胸腔镜肺大疱切除术患者血气分析及血流动力学的影响

目的 探讨单肺通气时应用不同水平的呼气末正压（PEEP）对胸腔镜肺大疱切除术患者术中血气分析及血流动力学的影响.方法 将78例行胸腔镜肺大疱切除术患者按随机数字表法分为三组,每组26例：Ⅰ组双肺通气后仅给予单肺间歇正压通气（IPPV）,Ⅱ组双肺通气后给予单肺IPPV加PEEP5 cmH2O（1 cmH2O=0.098 kPa）,Ⅲ组双肺通气后给予单肺IPPV加PEEP 10 cmH2O.记录并比较三组平卧位双肺通气、侧卧位双肺通气、单肺通气10和30 min的血气分析和血流动力学.结果 三组患者脉搏血氧饱和度均维持在0.99～ 1.00.三组各时间点pH值、剩余碱、动脉血二氧化碳分压（PaCO2）、HCO3-比较差异均无统计学意义（P＞0.05）.Ⅱ、Ⅲ组单肺通气10,30 min动脉血氧分压（PaO2）明显高于Ⅰ组（336.2±113.2）,（348.5±109.7） mmHg（1mmHg=0.133 kPa）比（285.0±103.5） mmHg,（357.6±104.0）,（358.9±103.2） mmHg比（276.0±107.2） mmHg],差异有统计学意义（P＜0.05）,但均在正常范围内,Ⅱ组和Ⅲ组比较差异无统计学意义（P＞0.05）.三组各时间点心率、平均动脉压、左心室射血时间、体循环血管阻力比较差异均无统计学意义（P＞0.05）.Ⅱ组和Ⅲ组单肺通气10,30 min每搏输出量、心输出量明显低于本组平卧位双肺通气、侧卧位双肺通气及Ⅰ组同期,差异均有统计学意义（P＜0.05）,但均在正常范围内,Ⅱ组和Ⅲ组比较差异无统计学意义（P＞0.05）.结论 双肺通气后给予单肺IPPV加PEEP 5 cmH2O在胸腔镜肺大疱切除术中能维持满意的PaO2和PaCO2,血流动力学变化不明显；但PEEP 5 cmH2O较仅IPPV能进一步提高PaO2,而PEEP 10 cmH2O却没有进一步提高PaO2.

Effect of different levels of positive pressure during one-lung ventilation on blood gas and hemodynamics in patients with thoracoscopic lung bullae resection surgery

Objective To investigate the effect of different levels of positive pressure （PEEP） during one-lung ventilation on blood gas and hemodynamics in patients with thoracoscopic lung bullae resection surgery.Methods Seventy-eight patients undergoing thoracoscopic lung bullae resection surgery were divided into three groups by random number table method,26 cases in each：group Ⅰ was only given one-lung intermittent positive pressure ventilation （IPPV） after two-lung ventilation,group Ⅱ was given one-lung IPPV and PEEP 5 cmH2O （1 cmH2O =0.098 kPa） after two-lung ventilation,group Ⅲ was given one-lung IPPV and PEEP 10 cmH2O after two-lung ventilation.Blood gas and hemodynamics were recorded and compared in the supine position and lateral position two-lung ventilation,one lung ventilation 10 and 30 min among three groups.Results Oxygen saturation was maintained at 0.99-1.00 in three groups.pH value,base excess,arterial carbondioxide partial pressure （PaCO2） and HCO3-at each time point in three groups had no statistical significance （P 〉 0.05）.Arterial oxygen partial pressure （PaO2） in group Ⅱ and group Ⅲ at one-lung ventilation 10,30 min was significantly higher than that in group Ⅰ （336.2 ± 113.2）,（348.5 ± 109.7） mmHg （1 mmHg =0.133 kPa） vs.（285.0 ± 103.5） mmHg,（357.6 ± 104.0）,（358.9 ±103.2） mmHg vs.（276.0 ± 107.2） mmHg] （P 〈0.05）,but were within the normal range,there was no statistical difference between group Ⅱ and group Ⅲ （p 〉 0.05）.Heart rate,mean arterial pressure,left ventricular ejection time,systemic vascular resistance at each time point in three groups had no statistical significance （P 〉0.05）.Stroke volume,cardiac output in group Ⅱ and group Ⅲ at one-lung ventilation 10,30 min were lower than those in supine position and lateral position two-lung ventilation and the same period in group Ⅰ （P 〈 0.05）,but were within the normal range,there were no statistical differences between group Ⅱ and group Ⅲ （p 〉 0.05）.Conclusions Two-lung ventilation after one-lung IPPV and PEEP 5 cmH2O in thoracoscopic lung bullae resection surgery can maintain satisfactory PaO2 and PaCO2,hemodynamic change is not obvious; PEEP 5 cmH2O compares with only IPPV can further improve PaO2,but PEEP 10 cmH20 cant further improve PaO2.