体外二氧化碳清除技术治疗儿童急性呼吸窘迫综合征的初步探讨

The preliminary study of extracorporeal carbon dioxide removal in acute respiratory distress syndrome for a pediatric patient

目的:近年来体外二氧化碳清除技术(ECCO 2R)越来越多地应用于救治危重急性呼吸衰竭患者,但在儿童应用非常少。我院PICU采用持续肾替代治疗(CRRT)平台开展ECCO 2R,为1例高碳酸血症的急性呼吸窘迫综合征(ARDS)患儿成功提供部分呼吸支持,为儿童ARDS采用ECCO 2R治疗提供临床参考。方法:我院PICU收治的1例腺病毒肺炎、重度ARDS患儿,在体外膜肺氧合(ECMO)撤机后出现高碳酸血症,采用CRRT平台开展ECCO 2R进行部分呼吸支持,取得良好效果。结果:患儿,男,1岁4个月,因腺病毒肺炎、重度ARDS,行机械通气和静脉-动脉ECMO治疗,ECMO治疗25 d,撤离ECMO后出现严重的高碳酸血症。在CRRT平台上,采用血液净化系统体外循环串联膜肺,开展二氧化碳清除治疗。治疗1 h后,pH值升高11.2%(从7.222升至7.303),PCO 2下降29.1%(从72.6 mmHg降至51.5 mmHg,1 mmHg=0.133 kPa);治疗6 h,高频震荡通气模式下平均气道压下降5 cmH 2O(从20 cmH 2O降至15 cmH 2O,1 cmH 2O=0.098 kPa)。ECCO 2R系统CO 2清除率为29.1 mL/min。ECCO 2R治疗72 h因膜肺血栓形成停止治疗。撤离ECCO 2R后监测血气无CO 2升高。患儿有创机械通气39 d,无创通气5 d,成功撤离呼吸机,PICU住院54 d,好转出院。出院后随访2年,生长发育良好,运动耐力仍差。结论:ECCO 2R治疗儿童ARDS高碳酸血症,可有效降低PCO 2,维持正常pH值,同时降低呼吸机条件,有助于实施超保护性肺通气,为ECMO撤机提供过渡治疗。

Objective Extracorporeal carbon dioxide removal(ECCO2R)is a technique that aims to decarboxylate the blood and thus to correct hypercapnia and respiratory acidosis in acute respiratory failure,but is rarely used in children.We successfully completed the ECCO2R treatment for a pediatric case with adenovirus pneumonia,severe acute respiratory distress syndrome(ARDS)and hypercapnia in PICU,which provided clinical references for the use of ECCO2R in acute respiratory failure for children.Methods A patient with adenovirus pneumonia and severe ARDS was successfully treated with ECCO2R-continuous renal replacement therapy(CRRT)combined system after weaning from extracorporeal membrane oxygenation(ECMO).We reported the treatment process,ECCO2R treatment effect and side effects,so as to provide clinical reference for ECCO2R treatment of children with ARDS.Results One-year and four-month-old boy was treated with mechanical ventilation and venous-arterial ECMO due to adenovirus pneumonia and severe ARDS.After ECMO treatment for 25 days,he developed severe hypercapnia after weaning from ECMO.ECCO2R was initiated.The pH value increased by 11.2%(from 7.222 to 7.303)1 hour after ECCO2R treatment,partial pressure of blood carbon dioxide(PCO2)decreased by 29.1%(from 72.6 mmHg to 51.5 mmHg,1 mmHg=0.133 kPa)and the average airway pressure of high-frequency ventilation decreased by 5 cmH2O(from 20 cmH2O to 15 cmH2O,1 cmH2O=0.098 kPa)after 6 hours of ECCO2R.The CO2 removal rate of ECCO2R system was 29.1 mL/min.It was stopped because of ECCO2R-membrane clotting after 72 h.There was no increase of PCO2.Extubation was successfully after undergoing invasive mechanical ventilation for 39 days and with noninvasive ventilation for 5 days.The boy was hospitalized in PICU for 54 days,improved and discharged from the hospital.Followed up for 2 years after discharge,the growth and development were good,but the strenuous exercise endurance was still poor.Conclusion ECCO2R is effective in improving gas exchange,reducing PCO2 and lowering ventilator pressure in children with ARDS and hypercapnia,which allow more protective ventilation.ECCO2R provide transitional treatment for ECMO weaning and provide meaningful clinical reference for the use of ECCO2R as part of respiratory support in children with respiratory failure.