Circuit lifespan during continuous renal replacement therapy for combined liver and kidney failure

Purpose: To evaluate circuit lifespan (CL) and bleeding risk during continuous renal replacement therapy (CRRT), in combined liver and renal failure. Methods: Single-center retrospective analysis of adults with acute liver failure or decompensated cirrhosis who received CRRT, without anticoagulation or with heparinization in intensive care unit. Results: Seventy-one patients with 539 CRRT circuits were evaluated. Median overall CL was 9 (6-16) hours. CL was 12 (7-24) hours in 51 patients never anticoagulated for CRRT. In 20 patients who subsequently received heparinization, CL was 7 (5-11) hours without anticoagulation, which did not improve with systemic or regional heparinization (P=.231), despite higher peri-circuit activated partial thromboplastin time (APTT) and heparin dose. Using multivariate linear regression, patients with higher baseline APTT or serum bilirubin, or who were not mechanically ventilated, had longer CL (P<.05). Additionally, peri-circuit thrombocytopenia (P<.0001) or higher international normalized ratio (P<.05) predicted longer CL. Of 71 patients, 33 had significant bleeding events. Using multivariate logistic regression, patients with higher baseline APTT, vasoactive drug use >24 hours, or thrombocytopenia, had more bleeding complications (P<.05). Decreasing platelet counts (especially <50 x 10(9)/mm(3)) had an incremental effect on CL (P<.0001). Conclusion: CRRT CL is short in patients with liver failure despite apparent coagulopathy. Thrombocytopenia predicts longer CL and bleeding complications.