Timing of continuous renal replacement therapy in severe acute kidney injury patients with fluid overload: A retrospective cohort study

We aimed to evaluate the association of early versus late initiation of Continuous renal replacement therapy (CRRT) with mortality in patients with fluid overload. This was a retrospective cohort study of patients with fluid overload (FO) treated with CRRT due to severe acute kidney injury (AKI) between January 2015 and December 2017 in a mixed medical intensive care unit of a teaching hospital in Beijing, China. Patients were divided into early (≤15 h) and late (>15 h) groups based on the median time from ICU admission to CRRT initiation. The primary outcome was all-cause mortality at day 60. Multivariable Cox model analysis was used for analysis. The study patients were male predominant (84/150) with a mean age of 64.8 ± 16.7 years. The median FO value before CRRT initiation was 10.1% [6.2–16.1%]. The 60-day mortality rates in the early vs the late CRRT groups were 53.9% and 73%, respectively. On multivariable Cox modelling, the late initiation of CRRT was independently associated with an increased risk of death at 60 days (HR 1.75, 95% CI 1.11–2.74, p = 0.015). Early initiation of CRRT was independently associated with survival benefits in severe AKI patients with fluid overload. •We evaluated the timing of continuous renal replacement therapy in patients with fluid overload.•Multivariable Cox regression models with restricted cubic splines were applied.•Early CRRT initiation might be associated with survival benefits among severe AKI patients with fluid overload in the ICU.