保护性肺通气策略在全身麻醉下俯卧位脊柱外科手术中的应用

Effects of protective ventilation on patients undergoing posterior spine surgery in prone position during general anesthesia

目的探讨保护性肺通气策略对俯卧位脊柱外科手术病人氧合功能和全身炎性反应的影响。方法选择60例拟在全身麻醉下行俯卧位脊柱外科手术的病人,随机分为常规通气组(潮气量VT=10 m L/kg,呼气末正压PEEP=0)或保护性肺通气组(VT=6 m L/kg,PEEP=5 cm H2O,每30分予手法肺复张1次)。记录术中主要的通气参数,并间隔1 h行动脉血气分析。分别采集麻醉诱导前、手术结束前、术后6 h和术后24 h采集病人外周血,检测血浆中的IL-6、TNF-α、IL-8和IL-1β的表达水平。结果与常规通气组相比,保护性肺通气组动脉血CO2水平明显升高[(34±5. 6) mm Hg比(39±5. 4) mm Hg,P <0. 001],但动脉血氧分压和气道峰压差异无统计学意义[(192±24. 6) mm Hg比(185±31. 5) mm Hg,P=0. 34;(25±3. 2) cm H2O比(23±4. 5) cm H2O,P=0. 052]。手术后血浆中的炎性因子表达水平显著升高,但两组之间差异无统计学意义。结论与常规通气组相比,保护性肺通气策略并不能减轻俯卧位脊柱外科手术病人的全身炎性反应或者改善病人的氧合功能。保护性肺通气策略在全身麻醉中可能发挥保护作用,但与术式或体位具有相关性。

Objective To evaluate the effects of protective ventilation strategy on the oxygenation and inflammatory response in patients undergoing spinal surgery in prone position.Methods 60 patients scheduled for the spinal surgery in prone position were randomized to receive either conventional ventilation(V T=10 mL/kg,PEEP=0)or protective ventilation(V T=6 mL/kg,PEEP=5cmH2O,with recruitment maneuvers per 30 min).Intra-operative ventilation parameters were recorded and blood gas analysis was performed per hour.Blood samples were collected at baseline,end of surgery,6 hours post-operation and 12 hours post-operation.The levels of IL-6,TNF-α,IL-8 and IL-1βwere determined.Results As compared to conventional ventilation,patients with protective ventilation had higher levels of PaCO2(34±5.6 vs.39±5.4 mmHg,P<0.001),but no significant difference was observed with respect to the PaO2 or the peak air pressure(192±24.6 vs.185±31.5 mmHg,P=0.34;25±3.2 vs.23±4.5 cmH2O,P=0.052).Surgical insult increased the plasma cytokines expressions,however,there was no statistically difference between conventional ventilation and protective ventilation.Conclusions As compared to conventional ventilation,protective ventilation did not alleviate the systemic inflammatory response or improve the oxygenation function in patients receiving spinal surgery in prone position.Protective ventilation might have some beneficial effects in general anesthesia,which could be confounding by different surgical types and positions.