Transport On Extracorporeal Membrane Oxygenation Vs Mechanical Ventilation:a Case-control Study

Objective:By comparing the clinical data and ventilator parameters of 40 cases on the support of ECMO or mechanical ventilation,the better mode of inter-hospital transporting was evaluated.Methods:The clinical data of 40 patients with severe ARDS who were referred to our center from January 2013 to October 2018 were retrospectively analyzed.19patients were transported with ECMO as the experimental group and 21 patients were transported with ventilator as the control group.The transport status,clinical characteristics,vital signs,ventilator parameters and Murray score before and after transport were compared between the two groups.Result:The age and expected mortality of ECMO transport group were higher than the control group[age?years?65?38,67?vs 58?40,62?,p=0.032;expected mortality?%?90.23?76.52,93.21?vs 81.45?73.86,86.46?,p=0.013].There was no significant difference in acute physiology and chronic health evaluation II?APACHE II?,transit distance and transit time between the two groups[APACHE?score:37?32,40?vs 24?20,35?,p=0.078;transit distance?km?:38?16.1,70.5?vs 41?14.0,76.5?,p=0.105;transit time?min?:58?48.0,77.5?vs 42?36.5,66.0?,p=0.103].There were no significant difference in heart rate?HR?,respiratory rate?RR?,blood pressure?BP?,respiratory index?PaO ₂/FiO₂?,inspiratory pressure and inhaled oxygen concentration?FiO₂?before transportation[HR?beat/min?:145±15 vs 132±15,p=0.124;RR?beat/min?:35±4 vs 32±4,p=0.098;BP?mmHg?115±20 vs 120±10,P=0.079;PaO₂/FiO₂?mmHg?:65±16 vs 64±15,p=0.117;inspiratory pressure?cmH₂O?:37±2 vs 38±3,p=0.075;FiO₂:1.00±0.00 vs 1.00±0.00].Murray score of ECMO transport group was higher than the control group,and the difference was statistically significant[Murray score:3.5±0.2 vs 3.5±0.3,p=0.975].There was significant difference in HR,RR,FiO₂/PaO₂,inspiratory pressure and FiO₂ between the two groups[HR?beat/min?:98±14 vs 137±14,p=0.003;RR?beat/min?:23±3 vs 33±4,p=0.001;PaO₂/FiO₂?mmHg?:148±15 vs 42±6,p=0.003;inspiratory pressure?cmH₂O?:20±1 vs 35±4,p=0.001;FiO₂:0.30±0.03 vs 0.98±0.06,p=0.001],but there was no significant difference in Murray score between the two group[Murray score:3.5±0.2?3.5±0.3,p=0.975].The HR,RR,FiO₂/PaO₂,inspiratory pressure and FiO₂ in ECMO transport group before transportation were significantly different from those at transport initiation[HR?beat/min?:145±15 vs 98±14,p=0.001;RR?beat/min?:35±4 vs 23±3,p=0.002;PaO₂/FiO₂?mmHg?:65±16 vs 148±15,p=0.003;inspiratory pressure?cmH₂O?:37±2 vs 20±1,p=0.001;FiO₂:1.00±0.00 vs0.30±0.03,p=0.001],while Murray score and FiO₂/PaO₂ before transportation were significantly different in control group[Murray score:3.5±0.2 vs 3.5±0.3,p=0.975;PaO₂/FiO₂?mmHg?:64±15 vs 42±6,p=0.010].In the ECMO transport group,8 survived and discharged,11 died during hospitalization;in the conventional transport group,8 survived and 13 died,of which 4 were related to hypoxia and aggravation of lung injury during transport.There was no significant difference in actual mortality between the two groups[?%?:57.9 vs 61.9,p=0.795].Conclusion:For severe ARDS patients,inter-hospital transport with ECMO is better than mechanical ventilation,which is conducive to lung protection.In addition,It is safe and feasible to carry out ECMO transport with the support of proper equipment and experienced professional and technical team.Reasonable staffing,adequate preparation of materials,appropriate arrangement of vehicle space and close cooperation are the key to transport safely and stably and improve the treatment rate of ECMO.