Renal function and clinical outcomes in survivors of out-of-hospital cardiac arrest.

BACKGROUND

Comprehensive studies about renal-function changes in the context of out-of-hospital cardiac arrest (OHCA) have been lacking. Therefore, we investigated the impact of renal function on clinical outcomes among patients with OHCA.

METHOD

This retrospective cohort study enrolled consecutive patients with OHCA between June 2017 and December 2021. Acute kidney injury (AKI) was defined based on the "Kidney Disease: Improving Global Outcomes (KDIGO)" guidelines. AKI recovery was defined as a decrease in serum creatinine below the level determined in the definition of AKI. Clinical outcomes included neurological outcomes and all-cause mortality.

RESULT

A total of 258 patients were enrolled, including 35 patients with underlying end-stage renal disease (ESRD). Among patients without ESRD, 82.5% developed AKI, of which 31.0% achieved AKI recovery, while 61.0% were discharged with impaired renal function. Multivariable analysis using regression models revealed that unfavorable neurological outcomes at discharge and higher mortality at 2 years were associated with AKI (odds ratio [OR] 7.684, 95% confidence interval (CI) 2.683-22.010,  0.001; hazard ratio [HR] 2.159, 95% CI 1.272-3.664,  0.004), AKI without recovery (OR 5.275, 95% CI 2.049-13.583,  0.001; HR 5.470, 95% CI 3.304-9.862,  0.001), and impaired pre-discharge renal function (OR 3.164, 95% CI 1.442-6.940,  0.004; HR 2.876, 95% CI 1.861-4.443,  0.001). Compared to those without ESRD, patients with underlying ESRD had similar neurological outcomes and mortality.

CONCLUSION

AKI, AKI without recovery, and impaired pre-discharge renal function were significantly correlated with worse clinical outcomes in OHCA among patients without ESRD, while underlying ESRD did not lead to worse clinical outcomes.