Short-and long-term outcomes of sustained low efficiency dialysis vs continuous renal replacement therapy in critically ill patients with acute kidney injury

Abstract

Background: Sustained low efficiency dialysis (SLED) has emerged as an alternative to continuous renal replacement therapy (CRRT) for the treatment of acute kidney injury (AKI) in critically ill patients. However, there is limited information on the short- and long-term outcomes of SLED compared to CRRT.

Methods: We conducted a retrospective cohort study of patients with AKI who commenced either SLED or CRRT in ICUs at a tertiary care hospital in Toronto, Canada. The primary outcome was 90-day all-cause mortality. Secondary outcomes included mortality at one year, and dialysis dependence at 90 days and one year. All outcomes were ascertained by linkage to provincial datasets.

Results: We identified 284 patients, of whom 95 and 189 commenced SLED and CRRT, respectively. Compared to SLED recipients, more CRRT recipients were mechanically ventilated (96% vs 86%, p = 0.002) and receiving vasopressors (94% vs 84%, p = 0.01) at the time of RRT initiation. At 90 days following RRT initiation, 52 (55%) and 126 (67%) SLED and CRRT recipients, respectively, died (adjusted risk ratio (RR) 0.91, 95% CI 0.75-1.11). There was no inter-modality difference in time to death through 90 days (adjusted hazard ratio 0.90, 95% CI 0.64-1.27). Among patients surviving to Day 90, a higher proportion of SLED recipients remained RRT dependent (10 (23%) vs 6 (10%) CRRT recipients, adjusted RR 2.82, 95% CI 1.02-7.81). At one year, there was no difference in mortality or dialysis dependence.

Conclusions: Among critically ill patients with acute kidney injury, mortality at 90 days and one year was not different among patients initiating SLED as compared to CRRT.

Keywords: Acute kidney injury; Continuous renal replacement therapy; Sustained low efficiency dialysis.