Fluid balance during acute phase extracorporeal cardiopulmonary resuscitation and outcomes in OHCA patients: a retrospective multicenter cohort study

The association between fluid balance and outcomes in patients who underwent out-of-hospital cardiac arrest (OHCA) and received extracorporeal cardiopulmonary resuscitation (ECPR) remains unknown. We aimed to examine the above relationship during the first 24 h following intensive care unit (ICU) admission.

We performed a secondary analysis of the SAVE-J II study, a retrospective multicenter study involving OHCA patients aged ≥ 18 years treated with ECPR between 2013 and 2018 and who received fluid therapy following ICU admission. Fluid balance was calculated based on intravenous fluid administration, blood transfusion, and urine output. The primary outcome was in-hospital mortality. The secondary outcomes included unfavorable outcome (cerebral performance category scores of 3–5 at discharge), acute kidney injury (AKI), and need for renal replacement therapy (RRT).

Overall, 959 patients met our inclusion criteria. In-hospital mortality was 63.6%, and the proportion of unfavorable outcome at discharge was 82.0%. The median fluid balance in the first 24 h following ICU admission was 3673 mL. Multivariable analysis revealed that fluid balance was significantly associated with in-hospital mortality (odds ratio (OR), 1.04; 95% confidence interval (CI), 1.02–1.06; p < 0.001), unfavorable outcome (OR, 1.03; 95% CI, 1.01–1.06; p = 0.005), AKI (OR, 1.04; 95% CI, 1.02–1.05; p < 0.001), and RRT (OR, 1.05; 95% CI, 1.03–1.07; p < 0.001).

Excessive positive fluid balance in the first day following ICU admission was associated with in-hospital mortality, unfavorable outcome, AKI, and RRT in ECPR patients. Further investigation is warranted.