Early and intensive continuous hemofiltration for severe renal failure after cardiac surgery

Background. The aim of this study was to test whether early and intensive u se of continuous venovenous hemofiltration (CVVH) achieved a better than pr edicted outcome in patients with severe acute renal failure undergoing card iac operations, and whether a simple and yet accurate model could be develo ped to predict their outcome before starting CVVH. Methods. Medical record analysis with collection of demographic, clinical, and outcome information was used. Results. Sixty-five consecutive patients were treated with early and intens ive CVVH (mean operation to CVVH time, 2.38 days; pump-controlled ultrafilt ration rate, 2 L/h) after coronary artery bypass grafting (56.9%), single v alve procedure (16.9%), or combined operations (26.2%). In 32.3% of patient s, intraaortic balloon counterpulsation was required and 20% of patients we re emergencies. Sustained hypotension despite inotropic and vasopressor sup port occurred in 40% of patients and prolonged mechanical ventilation in 58 .5%. Using an outcome prediction score specific for acute renal failure, th e predicted risk of death was 66%. Actual mortality was 40% (p = 0.003). Us ing multivariate logistic regression analysis and neural network analysis, patient outcome could be predicted with good levels of accuracy (receiver o perating characteristic 0.89 and 0.9, respectively). Conclusions. Early and aggressive CVVH is associated with better than predi cted survival in severe acute renal failure after cardiac operations. Using readily available clinical data, the outcome of such patients can be predi cted before the implementation of CVVH. (C) 2001 by The Society of Thoracic Surgeons.