ABSTRACT
Objectives: Data about COVID-19 patients treated with veno-arterial-ECMO (VA-ECMO) is limited. Reported survival rates range from 27.9% to 77.8%, depending on VA-ECMO indication. A subgroup of patients suffers from circulatory failure due to a COVID-19 associated hyperinflammatory state (CovHI). In these patients, differentiation between inflammation and sepsis is difficult but important. In this retrospective case series, differential diagnoses of COVID-19 associated refractory circulatory failure and survival rates in different indications for VA-ECMO are investigated. Method(s): Retrospective analysis of 28 consecutive COVID-19 patients requiring VA-ECMO at the University Hospital Regensburg between March 2020 and May 2022. Specific treatment for COVID-19 was in accordance with respective guidelines. Mycotic infections were either invasive or met current definitions of COVID19-associated-pulmonary aspergillosis. Result(s): At VA-ECMO initiation, median age was 57.3 years (IQR: 51.4 - 61.8), SOFA score 16 (IQR: 13 - 17) and norepinephrine dosing 0.53mug/kg/min (IQR: 0.32 - 0.78). Virus-variants were: 61% wild-type, 14% Alpha, 18% Delta and 7% Omicron. Survival to hospital discharge was 39%. 17 patients were primarily supported with VA-ECMO only (survival 42%), 3 patients were switched from VV to VA-ECMO (survival 0%), and 8 patients were converted from VA to VAV or VV-ECMO (survival 50%). Indications for VA-ECMO support were pulmonary embolism (PE) (n=5, survival 80%), right heart failure due to secondary pulmonary hypertension (n=5, survival 20%), cardiac arrest (n=4, survival 25%), acute left heart failure (ALHF) (n=11, survival 36%) and refractory vasoplegia (n=3, survival 0%). Inflammatory markers at VA-ECMO initiation were higher in patients with ALHF or vasoplegia;in these patients a higher rate of invasive fungal infections (10/14, 71% vs. 4/14, 29%;p=0.023) compared to the other patients was found. Conclusion(s): Survival on VA-ECMO in COVID-19 depends on VA-ECMO indication, which should be considered in further studies and clinical decisions making. Circulatory failure due to vasoplegia should be considered very carefully as indication for VA-ECMO. A high rate of mycotic infections mandates an intense microbiological workup of these patients and must be considered as an important differential diagnosis to CovHI.
ABSTRACT
Objectives: Treatment of severe respiratory distress syndrome (ARDS) due to COVID-19 by veno-venous extracorporeal membrane oxygenation (VV-ECMO) had a mortality of up to 70% in Germany. Many patients with COVID-19 need VV-ECMO support longer than 28 days (long-term VV-ECMO). Evidence on mortality, complications during intensive care, functional status after discharge and mortality-predictors for patients supported with long-term VV-ECMO is lacking. Method(s): Retrospective study of 137 consecutive patients treated with VV-ECMO for ARDS due to COVID-19 at University Hospital Regensburg from March 2020 to March 2022. Result(s): 38% (n=52;87% male) of patients needed longterm VV-ECMO support. In these, SOFA score (median [IQR]) at ECMO initiation was 9 [8-11], age 58.2 [50.6- 62.5] years, PaO2/FiO2-ratio 67 [52-88] mmHg, pCO262 [52-74] mmHg, Murray-Score 3.3 [3.0-3.6] and PEEP 15 [13 - 16] cmH2O. Duration of long-term support was 45 [35-65] days. 26 (50%) patients were discharged from the ICU. Only one patient died after hospital discharge. At VVECMO initiation, baseline characteristics did not differ between deceased and survivors. Complications were frequent (acute kidney injury: 31/52, renal replacement therapy: 14/52, pulmonary embolism: 21/52, intracranial hemorrhage 8/52, major bleeding 34/52 and secondary sclerosing cholangitis: 5/52) and more frequent in the deceased. Karnofsky index (normal 100) after rehabilitation was 70 [57.5-82.5]. Twelve of the 18 patients discharged from rehabilitation had a satisfactory quality of life according to their own subjective assessment. Four patients required nursing support. Mortality-predictors within the first 30 days on VV-ECMO only observed in those who deceased later, were: Bilirubin >5mg/dl for > 7 days, pulmonary compliance <10ml/mbar for >14 days, and repeated serum concentrations of interleukin 8 >150ng/L. Conclusion(s): Long-term extracorporeal lung support in patients with COVID-19 resulted in 50 % survival and subsequently lead to a satisfactory quality of life and functionality in the majority of patients. It should preferably be performed in experienced centers because of a high incidence of complications. Several findings during the early course were associated with late mortality but need validation in large prospective studies.