Résumé
Objectives: Patients with severe COVID-19 infections have been shown to have prolonged periods of coma followed by meaningful neurological recovery. Therefore, neurological prognostication is challenging, particularly in those who require veno-venous extracorporeal membrane oxygenation (VV-ECMO) support. We hoped to evaluate which variables can be considered when trying to predict neurological recovery. Method(s): We conducted a case-control retrospective chart review of patients on VV-ECMO from March 2020 to January 2022. This time-frame was selected to limit the effect of post-pandemic changes in sedation practices. Our outcome was duration of unconsciousness, defined as days with GCS motor score <6. We first conducted a matched cohort analysis, comparing COVID and non-COVID patients. We then performed a Classification and Regression Tree (CART) analysis to determine the Relative Variable Importance (RVI) of clinical variables associated with duration of unconsciousness. Result(s): Our matched analysis included 52 patients, 27 (52%) of whom had COVID-19. There were no significant differences in the baseline characteristics of the groups (Table 1). Patients with COVID-19 had a significantly longer median duration on ECMO (p<0.001) and hospital length of stay (p=0.003). The median duration of unconsciousness was similar between COVID-19 and non-COVID patients (p=0.58). The CART analysis results (Figure 1) showed that the most important variables to predict duration of unconsciousness were successive variations in GCS (RVI 100%) and GCS standard deviation (RVI 99%). COVID positivity only had a weak predictability (RVI 4%). Conclusion(s): Our analysis has shown that in patients on VV-ECMO, those with COVID-19 spent a longer time on ECMO and in the hospital. While there was no significant difference in the duration of unconsciousness, we found that patients who had high fluctuations of GCS during ECMO had a shorter duration of coma. (Figure Presented).
Résumé
INTRODUCTION: Neurological prognostication is an important part of caring for critically ill patients and can help guide goals of care. This has become a challenge when caring for patients with severe COVID-19 pneumonia, as they have been shown to often have prolonged periods of coma followed by meaningful neurological recovery. However, this has not been studied in patients who require venovenous extracorporeal membrane oxygenation (VV-ECMO) support. We hypothesize that patients with COVID-19 pneumonia on VV-ECMO will have a more prolonged period of unconsciousness when compared to their COVID-negative counterparts. METHOD(S): We conducted a retrospective chart review of all patients who received VV-ECMO support at our institution from March 2020 to January 2022. This timeframe was selected to limit the effect of any changes in sedation practices that were brought about by the COVID-19 pandemic. We compared the daily Glascow Coma Scale (GCS) of patients with COVID-19 pneumonia to those who were cannulated for other etiologies. Our outcomes were duration of unconsciousness, which was defined as time from intubation to GCS motor score=6 for 48 hours, as well as changes in GCS over time. RESULT(S): Our preliminary analysis included 84 patients, 57 (68%) of whom were COVID-19 positive. There were no significant differences in the baseline characteristics of the groups, including initial Sequential Organ Failure Assessment score and need for renal replacement therapy. Patients with COVID-19 pneumonia had a significantly longer duration on ECMO in hours (952 vs 312, p< 0.001) and hospital length of stay in days (42 vs 30, p=0.01). There was no significant difference in the duration of unconsciousness (days) between the two groups (11 vs 9, p=0.21). However, the trend in GCS over time was notable as we found that patients with COVID-19 spent more days unresponsive, defined as a GCS=3 (8 vs 5, p=0.04). CONCLUSION(S): Our preliminary analysis found that in patients on VV-ECMO, those with COVID-19 pneumonia spent a longer time on ECMO and in the hospital. While there was no difference in the duration of unconsciousness, patients with COVID-19 spent more of that period unresponsive prior to recovery. While additional analysis is needed, this finding may assist providers when prognosticating neurological recovery.