允许性高碳酸血症在胸腔镜治疗新生儿先天性食管闭锁手术中的应用

Application of permissive hypercapnia in thoracoscopic surgery of neonates with congenital esophageal atresia

目的探讨允许性高碳酸血症(permissive hypercapnia,PHC)在胸腔镜治疗新生儿先天性食管闭锁手术中的应用效果。方法选择行胸腔镜下先天性食管闭锁(congenital esophageal atresia,CEA)I期吻合术的新生儿30例,男17例,女13例,出生1~5d,体重1.42~3.28kg,ASAⅡ或Ⅲ级。随机分为PHC组(P组)和对照组(C组),每组15例。两组新生儿均采用气管内插管静-吸复合全麻,FiO2100%,新鲜气流量2L/min。P组VT6ml/kg,C组VT_10ml/kg。根据气道压及血气分析结果,通过调节呼吸机RR和PEEP参数,维持P组PaCO_2为60~80mm Hg,C组PaCO_2为35~45mm Hg。记录气胸建立前(T0)、气胸建立后15min(T_1)、30min(T_2)、60min(T3)和气胸解除后15min(T4)的动脉血气分析。记录术后2h内气胸发生情况及术毕至撤离呼吸机时间。结果T_1时,P组P_(ET)CO_2明显高于C组[(73.93±3.53)mm Hg vs.(41.53±1.59)mm Hg,P<0.05],动脉血pH值明显低于C组(7.25±0.02vs.7.38±0.03,P<0.05),PaCO_2明显高于C组[(74.80±2.45)mm Hg vs.(41.93±1.39)mm Hg,P<0.05];T2时,P组P_(ET)CO_2明显高于C组[(73.46±3.04)mm Hg vs.(41.30±1.29)mm Hg,P<0.05],动脉血pH值明显低于C组(7.24±0.01vs.7.37±0.03,P<0.05),PaCO_2明显高于C组[(75.33±2.19)mm Hg vs.(42.01±1.31)mm Hg,P<0.05];T3时,P组P_(ET)CO_2明显高于C组[(74.13±2.85)mm Hg vs.(41.67±1.35)mm Hg,P<0.05],动脉血pH值明显低于C组(7.25±0.01vs.7.38±0.02,P<0.05),PaCO_2明显高于C组[(75.20±2.08)mm Hg vs.(42.13±1.19)mm Hg,P<0.05]。P组气胸发生率明显低于C组(6.7%vs.40.0%,P<0.05)。P组与C组术毕至撤离呼吸机时间差异无统计学意义[(3.6±0.6)d vs.(3.5±0.6)d]。结论允许性高碳酸血症(PaCO_260~80mm Hg)可以安全应用于胸腔镜治疗新生儿先天性食管闭锁手术,同时可以明显降低气胸的发生率。

Objective To investigate the application of permissive hypercapnia in the thoracoscopic surgery of neonates with congenital esophageal atresia.Methods Thirty newborns with congenital esophageal atresia,seventeen males,thirteen females,aged 1-5days,weighing 1.42-3.28 kg,ASA physical status Ⅱ or Ⅲ,undergoing the thoracoscopic surgery,were randomly divided into group P and group C,n=15in each group.The newborns were intratracheally intubated and adopted intravenous anesthesia combining inhalational anesthesia.FiO2 100%,fresh gas flow 2L/min,then adjusted the respirator parameters according to the results of airway pressure and arterial blood gas analysis.Group P maintained PaCO2 ranging at 60-80 mm Hg,group C maintained PaCO2 ranging at 35-45 mm Hg.Arterial blood gas analysis was conducted respectively before artificial pneumothorax（T0）,15 min after foundation of artificial pneumothorax（T1）,30 min after foundation of artificial pneumothorax（T2）,60 min after foundation of artificial pneumothorax（T3）and 15 min after artificial pneumothorax（T4）.Two hours after surgery,a chest X ray photograph was taken to observe pneumothorax.The time from the end of the surgery to the ventilator weaning was recorded.Results At T1-T3,the P（ET）CO2 [（73.93±3.53）mm Hg vs.（41.53±1.59）mm Hg,（73.46±3.04）mm Hg vs.（41.30±1.29）mm Hg,（74.13±2.85）mm Hg vs.（41.67±1.35）mm Hg]in group P were greatly higher than those in group C（P〈0.05）;the arterial blood pH value of group P（7.25±0.02 vs.7.38±0.03,7.24±0.01 vs.7.37±0.03,7.25±0.01 vs.7.38±0.02）were greatly lower than those in group C（P〈0.05）;PaCO2[（74.80±2.45）mm Hg vs.（41.93±1.39）mm Hg,（75.33±2.19）mm Hg vs.（42.01±1.31）mm Hg,（75.20±2.08）mm Hg vs.（42.13±1.19）mm Hg]were greatly higher than those in group C（P〈0.05）.The incidence of pneumothorax of group P was obviously lower than that of group C（6.7% vs.40.0%,P〈0.05）.There was no statistically significant difference of the time from the end of surgery to the ventilator weaning[（3.6±0.6）d vs.（3.5±0.6）d]between the two groups.Conclusion Permissive hypercapnia significantly reduces the incidence of pneumothorax in the thoracoscopic surgery of neonates with congenital esophageal atresia.Permissive hypercapnia（PaCO2 60-80 mm Hg）can be safely applied to the thoracoscopic surgery of neonates with congenital esophageal atresia.