4-Organ Sofa Score as Tool to Triage Crrt Use in Covid-19 Patients during Crisis Standards of Care

ABSTRACT

INTRODUCTION: Acute kidney injury requiring renal replacement therapy (AKI-RRT) is associated with high mortality, especially in the setting of COVID-19. During the peak of the delta wave in New Mexico in late 2021, crisis standards of care were declared and strategies to ration care were explored. Our hypothesis is that a simplified SOFA score in patients with COVID-19 and AKI-RRT may predict short-term mortality. METHOD(S) We retrospectively analyzed all COVID-19 patients started on CRRT for AKI in the medical ICU at our center between April 2020 and July 2021. A 4-organ SOFA score (4OSS), with renal and neurologic sub-scores excluded, was calculated at the time of CRRT initiation. Neurologic sub-score was excluded because it is subjective, inconsistently documented, and confounded by the frequent use of sedation and paralysis in severe COVID-19. ECMO patients were included and assigned the maximum respiratory sub-score. Patients started on RRT at an outside hospital, found to be incidentally COVID-positive, or on chronic dialysis were excluded. P values were obtained using 1-sided Mann-Whitney U tests. RESULT(S) 63 total COVID-19 patients on CRRT were identified with 73% 30-day mortality and 83% in-hospital mortality. The median 4OSS was 8 in both in-hospital survivors and non-survivors with interquartile range [IQR] of 4-9 and 7-9.75, respectively (difference between groups non-significant, p = 0.075). The median 4OSS was 7 [5.5- 8.5] and 8 [7-10] in 30-day survivors and non-survivors, respectively (p = 0.018). Those with 4OSS of >=10 (n=13, 20.6%) had 100% in-hospital mortality. CONCLUSION(S) Similar to other analyses of SOFA score in COVID-19, 4OSS at CRRT initiation in patients with COVID-19 and AKI-RRT appears to have limited prognostic ability, with substantial overlap in scores between survivors and non-survivors. However, while additional multicenter studies are needed, 4OSS of >=10 may identify a group of about 20% of COVID-19 patients with AKI-RRT and mortality approaching 100%. Given the absence of a superior validated metric, a 4OSS of >=10 may be a reasonable tool for triage of CRRT in the setting of crisis standards of care and CRRT machine or supply shortages. At a minimum, 4OSS could inform goals of care discussions prior to CRRT initiation in patients with COVID-19 complicated by AKI-RRT.