BackgroundMinimization of hemodynamic instability during renal replacement therapy (RRT) in patients with acute kidney injury (AKI) is often challenging. We examined the relative hemodynamic tolerability of sustained low efficiency dialysis (SLED) and continuous renal replacement therapy (CRRT) in critically ill patients with AKI. We also compared the feasibility of SLED administration with that of CRRT and intermittent hemodialysis (IHD).MethodsThis cohort study encompassed four critical care units within a single university-affiliated medical centre. 77 consecutive critically ill patients with AKI who were treated with CRRT (n = 30), SLED (n = 13) or IHD (n = 34) and completed at least two RRT sessions were included in the study. Overall, 223 RRT sessions were analyzed. Hemodynamic instability during a given session was defined as the composite of a > 20% reduction in mean arterial pressure or any escalation in pressor requirements. Treatment feasibility was evaluated based on the fraction of the prescribed therapy time that was delivered. An interrupted session was designated if < 90% of the prescribed time was administered. Generalized estimating equations were used to compare the hemodynamic tolerability of SLED vs CRRT while accounting for within-patient clustering of repeated sessions and key confounders.ResultsHemodynamic instability occurred during 22 (56.4%) SLED and 43 (50.0%) CRRT sessions (p = 0.51). In a multivariable analysis that accounted for clustering of multiple sessions within the same patient, the odds ratio for hemodynamic instability with SLED was 1.20 (95% CI 0.58-2.47), as compared to CRRT. Session interruption occurred in 16 (16.3), 30 (34.9) and 11 (28.2) of IHD, CRRT and SLED therapies, respectively.ConclusionsIn critically ill patients with AKI, the administration of SLED is feasible and provides comparable hemodynamic control to CRRT.

The treatment of established acute kidney injury (AKI) is largely supportive in nature. Renal replacement therapy remains the cornerstone of management for the minority of patients who have severe AKI. Optimization of renal replacement therapy may modulate the high mortality associated with AKI. Recent trials indicated that continuous renal replacement therapy does not confer a survival advantage as compared to intermittent hemodialysis. Furthermore, there is no evidence to support a more intensive strategy of renal replacement therapy in the setting of AKI. There is comparatively limited data regarding the ideal timing of renal replacement therapy initiation and the preferred mode of solute clearance.