Comparison of extracorporeal membrane oxygenation and mechanical ventilation for inter-hospital transport of severe acute respiratory distress syndrome patients / 中华危重病急救医学

ABSTRACT

Objective To compare inter-hospital transport and clinical outcome in severe acute respiratory distress syndrome(ARDS)patients whom were transported either on extracorporeal membrane oxygenation(ECMO) or on conventional ventilation,and to investigate the optimal means of inter-hospital transport. Methods Eleven patients with severe ARDS who were invalid under conventional ventilation and were transported from other hospitals to Tianjin Third Central Hospital from November 2009 to January 2014 were analyzed. Five patients were transported on ECMO(observation group)and 6 on conventional ventilation(control group). The clinical characteristics,outcomes, transportation,vital signs before and after transportation,respiratory parameters,and Murray score between two groups were compared. Results Patients in observation group were significantly older than those in control group〔years73(46,77)vs. 34(23,46),Z=-2.293,P=0.022〕. There was no significant difference between observation group and control group in acute pathologic and chronic health evaluationⅡ(APACHEⅡ)score,Murray score,oxygenation index(PaO2/FiO2)before transportation,transit time,and transit distance〔APACHEⅡscore36(33,39)vs. 27(23,35),Z=-1.830,P=0.067;Murray score3.5±0.3 vs. 3.4±0.2,t=0.667,P=0.524;PaO2/FiO2(mmHg, 1 mmHg=0.133 kPa)61±14 vs. 63±14,t=-0.249,P=0.809;transit time(minutes)24(18,74)vs. 79(41, 86),Z=-1.654,P=0.098;transit distance(km)12.9(8.3,71.8)vs. 72.4(39.5,86.8),Z=-1.651,P=0.099〕. There was no significant difference between two groups in vital signs and respiratory parameters before transportation. When arrived in ECMO centre,heart rate,respiratory rate,fractional inspired oxygen,inspiratory pressure and Murray score in observation group were significantly lower than those in control group〔heart rate(beat/min)102±16 vs. 136±8, t=-4.374, P=0.002;respiratory rate(beat/min)23±3 vs. 37±2,t=-7.967,P=0.000;fractional inspired oxygen0.40±0.05 vs. 0.96±0.09,t=-12.152,P=0.000;inspiratory pressure(cmH2O, 1 cmH2O=0.098 kPa)21±1 vs. 34±4,t=-6.887,P=0.000;Murray score2.7±0.2 vs. 3.8±0.2,t=-8.573, P=0.000〕,but PaO2/FiO2 was higher than that of control group(mmHg278±65 vs. 41±5 ,t=8.075,P=0.001). Four patients were survived in observation group,and one died from the shortage of oxygen induced lung injury deterioration during transportation. Three patients died in control group,which was directly associated with lung injury deterioration. Conclusion For patients with severe ARDS who need the support of ECMO,ECMO-assisted transfer is safer than conventional ventilation,but transfer should be implemented by experienced team.