神经调节辅助通气在长期机械通气患儿撤机中的应用

Application of neurally adjusted ventilatory assist in the weaning from prolonged mechanical ventilation in pediatrics

目的探讨神经调节辅助通气(NAVA)对长期机械通气(PMV)患儿撤机的临床效果及对呼吸力学相关参数的影响。方法回顾性分析2014年7月至2020年7月首都儿科研究所附属儿童医院重症监护室(PICU)12例符合PMV并应用NAVA(包括有创、无创NAVA)进行撤机管理的患儿资料。记录患儿主要诊断、病原学、氧合指数(OI)、小儿危重症评分(PICS)、机械通气治疗情况、呼吸力学指标、PICU住院时间及预后,评估过渡到NAVA后的相关并发症。NAVA通气前后呼吸力学参数和血气的比较采用秩和检验。结果12例患儿中11例有基础疾病,早产儿合并慢性肺部疾病8例,其中Wilson-Mikity综合征2例;先天性脐膨出1例;Prader-Willi综合征(PWS)1例;脊髓性肌萎缩症(SMA)1例。8例患儿主要诊断为急性呼吸窘迫综合征(ARDS)。总机械通气时间和PICU住院时间中位数分别为32.0(25.0,39.0)d和39.5(29.5,48.5)d;有创NAVA和无创NAVA通气时间中位数分别为5.5(3.8,6.3)d和7.0(5.0,9.5)d。撤机成功率100%,出院生存率100%。患儿均无与NAVA通气相关的并发症。NAVA通气6 h后,与同步间歇指令通气(SIMV)相比,呼吸力学参数无明显差异(均P>0.05);动脉血二氧化碳分压明显降低[43.50(41.75,46.00)mmHg比48.50(45.25,56.00)mmHg,1 mmHg=0.133 kPa](Z=-2.253,P=0.024);动脉血氧分压明显升高[68.00(65.00,72.25)mmHg比62.00(59.00,64.75)mmHg](Z=-2.733,P=0.006);OI明显下降[3.70(3.38,5.60)比5.90(4.58,7.08)](Z=-2.272,P=0.023)。结论采用NAVA模式对PMV患儿进行撤机管理,安全可靠、撤机成功率高;与SIMV模式相比,NAVA模式可明显改善通气和OI,尤其是慢性肺部疾病或撤机失败的PMV婴幼儿,推荐应用NAVA模式撤机。

Objective To investigate the clinical effect of neurally adjusted ventilatory assist(NAVA)on weaning from prolonged mechanical ventilation(PMV)in pediatrics and its influence on related parameters of respiratory mechanics.Methods A retrospective analysis was conducted on 12 children in the pediatric intensive care unit(PICU)of Children′s Hospital,Capital Institute of Pediatrics from July 2014 to July 2020.All the cases adopted NAVA for weaning from PMV,and the type of NAVA included invasive NAVA and non-invasive neurally adjusted ventilatory assist with NAVA.The main diagnosis,etiology,oxygenation index(OI),pediatric critical illness score(PCIS),treatment of mechanical ventilation(MV),respiratory mechanics indexes,length of stay in PICU and prognosis were recorded.Besides,the complications that happened after transition to NAVA were evaluated.The rank sum test was used for comparison of respiratory mechanics indexes and blood gas values before and after NAVA ventilation.Results Among the 12 children,11 cases had basic diseases.There were 8 premature infants complicated with chronic lung diseases.Two cases had Wilson-Mikity syndrome.One case had congenital omphalocele,1 case had Prader-Willi syndrome(PWS),1 case had spinal muscular atrophy(SMA).The main diagnosis of 8 children was acute respiratory distress syndrome(ARDS).The median duration of MV and PICU stay was 32.0(25.0,39.0)days and 39.5(29.5,48.5)days.The median duration of invasive NAVA and non-invasive-NAVA was 5.5(3.8,6.3)days and 7.0(5.0,9.5)days.All cases were successfully weaned from MV(100%),and the survival-to-discharge rate was 100%.There were no complications related to NAVA.After ventilation for 6 hours,no significant difference was observed in respiratory mechanical parameters between synchronized intermittent mandatory ventilation(SIMV)and NAVA(all P>0.05).However,compared with SIMV,NAVA significantly decreased the arterial partial pressure of carbon dioxide[43.50(41.75,46.00)mmHg vs.48.50(45.25,56.00)mmHg,1 mmHg=0.133 kPa](Z=-2.253,P=0.024),increased the arterial partial pressure of oxygen[68.00(65.00,72.25)mmHg vs.62.00(59.00,64.75)mmHg](Z=-2.733,P=0.006),and reduced the value of OI[3.70(3.38,5.60)vs.5.90(4.58,7.08)](Z=-2.272,P=0.023).Conclusions NAVA is a safe and effective approach to weaning from PMV in children.Compared to SIMV,NAVA can greatly improve ventilation and oxygenation.NAVA is strongly recommended to PMV infants with chronic lung diseases who have failed to wean from ventilation.