PULM15: COVID Cholangiopathy in patients supported on Veno-Venous ECMO support: Correlation or Causation?

Abstract

Study: The long-term effects of COVID-19 continue to be identified and have had undoubtedly devastating morbidity and mortality consequences. Despite the publication of numerous papers in the last several years, the definite morbidities that worsen mortality remain uncertain. The role of COVID-19 cholangiopathy is largely undefined. As more people survive severe COVID-19 infections, it is crucial to gain more insight into this disease process in order to improve management. Patients with any degree of COVID-19 infection are at risk for developing cholangiopathy, but those who experience severe infection necessitating extra-corporeal membrane oxygenation (ECMO) may be especially vulnerable to increased morbidity and mortality due to cholangiopathies. Methods: A retrospective chart review was performed on 94 patients with COVID-19 who were placed on ECMO for any period of time while in the ICU at a single academic institution between 2019-2020. Total bilirubin levels at admission, total bilirubin levels at discharge from the hospital, and highest total bilirubin levels during hospital stay were recorded as primary outcome to quantify the extent of cholangiopathy in patients who survived and those who did not survive. AST, ALT, INR, and right ventricle dysfunction during the same hospital stay were also recorded as secondary outcomes. A total of 658 instances of lab data were analyzed in these patients. Survival curves were generated by Kaplan-Meier method. Student’s t-test and descriptive statistics were used to analyze the data. Results: There was a 37% survival rate among the 94 patients. We found a significant difference in total bilirubin level at hospital discharge among survivors versus non-survivors (p=.0000904). There was also a significant difference in maximum INR between survivors and non-survivors (p=.027). A difference in highest total bilirubin level was observed in non-survivors, although it was not significant. No difference between AST and ALT values were observed between the two groups. Conclusion: The observed difference in total bilirubin levels at hospital discharge among patients with COVID-19 on ECMO suggests a real relationship between COVID-19 and hyperbilirubinemia. We recognized that ECMO can cause unconjugated hyperbilirubinemia due to hemolysis; however, we observed increases in conjugated bilirubin. Further investigation of this relationship may be used to guide preventive treatments and post-hospitalization recovery care.