(8830) APRV Avoids ECMO in Severe ARDS Patients Referred for ECLS

Introduction: Severe ARDS has mortality rates exceeding 45% particularly when meeting criteria for ECMO. APRV has been used for over 4 decades to improve oxygenation when failing conventional MV strategies and may reduce the need for ECMO rescue if implemented early.

METHODS : Retrospective study of all adult patients referred for V-V ECMO evaluation at UF-Jacksonville for ARDS from 7/17 – 8/2021 including COVID-19 illness that were managed on APRV without ECMO. The EMR was used to search for the datapoints: survival to discharge, P/F ratio at time of referral and then at 1, 6, and 24 hours after initiating APRV when ECMO was not implemented, paralytic and vasopressor usage prior to and 6 hours after initiating APRV, and lactate levels at time 0, 6 hours and 24 hours after initiating APRV.

Results: There were 65 consults for V-V ECMO due to ARDS that were managed on APRV without ECMO. The mean age was 40.1 years; 59% men and 41% women; category of ARDS was medical in 72%, trauma in 26%, and surgical in 2%. All patients were on ARDsnet ventilation strategy when referred. The survival to discharge was 79.3% with 50% going home, 39% to rehab, and 11% to an LTAC. The mean P/F ratio at time of evaluation was 77.1; 1 hour after initiating APRV it was 122.7; 6 hours after initiating it was 163.8; 24 hours after initiating it was 211.8 and the mean FiO2 at 24 hours was 59.2%. At time of evaluation 50.8% of patients were on paralytic infusions and 33.3% were on vasopressors while 6 hours after initiating APRV it was 0% for the former and 14.5% for the latter. Mean serum lactate was 3.1 mmol/L at time 0, then 2.6 mmol/L 6 hours after APRV was initiated, and 2.3 mmol/L 24 hours after initiating APRV.

Conclusions: We had excellent success using APRV to improve severe hypoxia in patients failing on standard ventilation using ARDSnet strategy, with a survival rate without ECMO of nearly 80%. The reduction in paralytic use and vasopressor requirements likely contributed to improved pulmonary and cardiovascular function allowing the vast majority of survivors to go home directly or home after short-term rehab stay. APRV should be considered in severe ARDS and may avoid the need for ECMO in some patients if applied before the patient is in extremis.