Indications for Dialysis in Acute Kidney Injury

Renal replacement therapy (RRT) can be used to support patient’s kidney function in cases of acute kidney injury (AKI). However, timing, modality, and dosing of RRT continue to remain in question. Recent studies have begun to provide data to help guide clinicians on when to initiate RRT, what form of RRT to use ranging from continuous venovenous hemofiltration (VVH) to intermittent hemodialysis, and the impact of high versus low-intensity dosing. Additionally, the risks associated with temporary vascular access with regard to thrombosis and infection, the impact of high efficiency and flux versus low efficiency and flux membranes, and options for anticoagulation in RRT for AKI are also discussed. This review contains 75 references. Key words: acute kidney injury, chronic kidney disease, continuous venovenous hemofiltration, continuous venovenous hemodialysis, renal replacement therapy, venovenous hemofiltration,

Circuit Survival during Continuous Venovenous Hemodialysis versus Continuous Venovenous Hemofiltration

Background: Continuous renal replacement therapy (CRRT) technique may affect circuit lifespan. A shorter circuit life may reduce CRRT efficacy and increase costs. Methods: In a before-and-after study, we compared circuit median survival time during continuous venovenous hemofiltration (CVVH) versus continuous venovenous hemodialysis (­CVVHD). We performed log-rank mixed effects univariate analysis and Cox mixed effect regression modeling to define predictors of circuit lifespan. Results: We compared 197 ­CVVHD and 97 CVVH circuits in 39 patients. There was no overall difference in circuit lifespan. When no anticoagulation was used, median circuit survival time was shorter for CVVH circuits (5 h, 95% CI 3–7 vs. 10 h, 95% CI 8–13, p < 0.01). Moreover, CVVHD, lower platelets levels, and longer activated partial thromboplastin time independently predicted longer circuit median survival time. Conclusions: CVVHD is associated with longer circuit median survival time than CVVH when no anticoagulation is used and is an independent predictor of circuit survival.