摘要目的 探讨呼吸心跳骤停复苏后危重患儿机械通气时肺保护通气策略及存活患儿出院90 d随访情况.方法 选择2011年1月至2016年6月贵阳市儿童医院儿童重症医学科收治因各种原因发生呼吸心跳骤停息儿489例.其中进行心肺复苏后机械通气251例,24 h内死亡或放弃治疗83例,存活＞24 h 168例,分为小潮气量通气组118例,常规潮气量通气组50例,根据潮气量调整呼气末正压通气(PEEP),监测动脉血氧分压[pa(O2)]、氧合指数(OD、血气分析、乳酸清除率等指标的变化,观察各组氧合改善、机械通气并发症的发生、撤机情况及患儿的转归情况.随访存活90 d患儿,包括出院后持续呼吸道表现、肺影像学检查及肺功能检查、神经系统检查.结果 1.小潮气量通气48 h氧合改善与常规潮气量通气比较,吸入氧体积分数(FiO2)(0.42 ±0.15比0.43 ±0.22)、pa(O2) (8.25 ±0.22比8.27±0.68)、OI(5.33 ±2.01比6.59±1.99)及乳酸清除率(61.05 ±1.87与60.93 ±2.71)差异均无统计学意义(t=1.645、1.165、2.302、2.037,均P＞0.05).2.小潮气量通气组呼吸机相关性肺损伤的发生率明显低于常规潮气量通气组,差异有统计学意义(x2=5.873,P＜0.05).3.2组不同潮气量通气比较,危重患儿的病死率差异无统计学意义(x2=1.063,P＞0.05).4.最终存活出院127例,随访出院30 d、90 d 62例存活患儿肺功能情况,与出院时比较肺功能均有所改善,潮气量、吸气与呼气时间比(I/E),达峰容积比(VP/VE)、达峰时间比(TP/TE)及呼吸频率(RR)均改善,差异均有统计学意义(F=43.225、6.108、68.821、78.237、20.361,均P＜0.05).5.神经系统检查及儿童脑功能分类量表评分,19例患儿存在神经功能障碍.结论 小潮气量通气在降低呼吸机相关性肺损伤的发生优于常规潮气量通气;改善呼吸心跳骤停复苏患儿的氧合及病死率并不优于常规潮气量组.动态监测呼吸力学指标有助于及时调整呼吸机参数并撤机,随访出院患儿大部分恢复良好,少数存在反复呼吸道感染及神经系统后遗症.

abstractsObjective To investigate the strategy of cardiopulmonary resuscitation (CPR) after lung protective mechanical ventilation in critical children and follow-up study of the survivals 90 d after discharge.Methods Four hundred and eighty-nine cases of respiratory cardiac arrest which occurred for various reasons from January 2011 to June 2016 were analyzed in Pediatric Intensive Care Unit (PICU) in Guiyang Children's Hospital,in which mechanical ventilation was performed after CPR in 251 cases,death,or giving up treatment within 24 h in 83 cases,children surviving ＞ 24 h in 168 cases,118 cases were assigned into small tidal volume ventilation group,and 50 cases into conventional tidal volume ventilation group,and according to the tidal volume to adjust positive end expiratory pressure ventilation (PEEP),and the oxygen partial pressure [pa (O2)] and the oxygen index (OI),the change of the indexes of blood gas analysis,lactic acid clearance,and oxygenation were also observed.To observe the complications of mechanical ventilation,the situation of withdrawing machine as well as the outcome of the children.Follow-up was conducted for 90 d,including continuous respiratory symptoms,lung imaging examination after discharge and lung function,nervous system examination.Results (1) After mechanical ventilation treatment of 48 hours,compared with the levels of fractional inspired oxygen (FiO2) (0.42 ± 0.15 vs.0.43 ± 0.22),pa (O2) (8.25 ± 0.22 vs.8.27 ± 0.68),OI (5.33 ± 2.01 vs.6.59 ± 1.99) and lactic acid clearance(61.05 ± 1.87 vs.60.93 ± 2.71) between the routine tidal volume ventilation group and the lower tidal volume ventilation group,showing that the difference had no statistical significance (t =1.645,1.165,2.302,2.037,all P ＞ 0.05).(2) In small tidal volume group,the incidence of ventilator associated lung injury was significantly lower than that in the conventional tidal volume group,and the difference was statistically significant (x2 =5.873,P ＜ 0.05).(3) Comparing 2 groups of different tidal volume ventilation,the mortality of critical ill children had no statistically significant difference (x2 =1.063,P ＞ 0.05).(4) One hundred and twenty-seven cases of children survived and were discharged,and compared with their discharge,the follow-up of 62 cases after discharge for 30 d,90 d showed that all the children's lung function improved,tidal volume,inspiratory and expiratory time ratio(I/E),volume ratio of peak(VP/VE),time ratio of peak(TP/TE) and breathing rate(RR) were also improved,and there was significant difference (F =43.225,6.108,68.821,78.237,20.361,all P ＜ 0.05).(5) Neurological examination and children's brain function classification rating scale showed that some children had nerve dysfunction.Conclusions Small tidal volume ventilation in reducing the occurrence of ventilator associated lung injury is superior to the conventional tidal volume ventilation.To improve case fatality rate of the children with cardiac arrest resuscitation and oxygenation is not better than the conventional tidal volume group.Dynamic monitoring is helpful to adjust breathing mechanics indexes and parameters and ventilator.Through the follow-up most of the discharged children recovered well,but a few had recurrent respiratory infection and neurological sequelae.