肺保护性通气降低高原地区全麻患者肺损伤的临床分析

目的:探讨肺保护性通气降低高原患者围术期机械通气相关肺损伤的风险。方法:择期行全麻手术的高原地区患者120例,年龄21~49岁,ASAⅠ~Ⅱ级,BMI 18~24 kg/m^2,随机分为肺保护性通气组(PV组)和常规通气组(CV组),每组60例。CV组为潮气量10 mL/kg,术中无呼气末正压(positive end-expiratory pressure,PEEP)和肺复张,通气频率12次/min,吸呼比1∶2;PV组为潮气量6 mL/kg,通气频率12次/min,吸呼比1∶2,PEEP 6 cmH2O(1 cmH2O=98.0665 Pa),每30 min进行一次肺复张。分别于麻醉诱导插管后5 min(T1)、机械通气后1 h(T2)、术毕拔管前(T3)记录气道峰压(Ppeak),计算肺顺应性Cdyn=VT/(Ppeak-Peep)]、肺氧合指数(OI=PaO2/FiO2)、肺泡-动脉血氧分压差(A-aDO2)、氧合指数(PaO2/FiO2),并记录患者的平均动脉压(MAP)、心率(HR)、血氧饱和度(SpO2)。结果:PV组T2、T3时Cdyn、OI明显升高(P<0.05),A-aDO2明显降低(P<0.05),2组的MAP、HR、SpO2变化无统计学意义,2组各个时点PaO2和PaCO2差异无统计学意义,PV组T3的Qs/Qt值明显低于CV组(P<0.05)。结论:肺保护性通气能降低高原患者围术期机械通气相关肺损伤的风险。

Clinical study of protective ventilation reducing lung injury in patients with general anesthesia in plateau area

Objective: To investigate the risk of lung injury associated with perioperative protective mechanical ventilation in patients living in plateau area. Methods: We chose 120 patients from plateau area who would receive general anesthesia, and randomly divided into the protective ventilation group (PV group) and the control ventilation group (CV group). In CV group, we used a tidal volume of 10 mL/kg, no positive end-expiratory pressure (PEEP) or lung re-expansion, ventilation frequency of 12 times/min, and a ratio of 1:2. In PV group, we used a tidal volume of 6 mL/kg, a ventilation frequency of 12 times/min, and a ratio of 1:2, PEEP 6 cmH2O(1 cmH₂O=98.066 5 Pa), and did lung re-expansion every half hour. We recorded lung compliance, pulmonary oxygenation index (OI=PaO₂/FiO₂), alveolar-arterial partial pressure difference (A-aDO₂), oxygenation index (PaO₂/FiO₂), average arterial pressure (MAP), heart rate (HR), and oxygen saturation (SpO₂) of the patients at 5 minutes after anesthesia induction(T1), 1 hour after mechanical ventilation(T2), and before extubation (T3) respectively. Results: In PV group, Cdyn and OI at T2 and T3 were significantly increased (P<0.05), and A-aDO₂ was significantly decreased (P<0.05). The changes in MAP, HR and SpO₂ in the two groups were not statistically significant. There was no significant difference in PaO₂ and PaCO₂ between the two groups at each time point. The Qs/Qt value of T3 in PV group was significantly lower than that in CV group (P<0.05). Conclusions: Protective ventilation can reduce the risk of lung injury associated with perioperative mechanical ventilation in patients living in plateau area.