Regional citrate anticoagulation in continuous venovenous hemodiafiltration

Over the past several years, continuous venovenous hemodiafiltration (CVVHD F) using pump driven devices has gained wide acceptance as a form of renal replacement therapy for critically ill patients with acute renal failure. M ore recently, regional citrate anticoagulation has proven useful as a metho d of anticoagulating CVVHDF circuits, particularly in those patients at hig h risk for bleeding. However, an easy and convenient method for guiding the dose of citrate infusion has not previously been described. We describe th e use of an algorithm using posthemofilter levels of ionized calcium to gui de the dose of administered regional citrate on the survival time and urea and creatinine clearances of 24 Hospal AN69HF hemofilters. Nine patients wi th acute and chronic renal failure requiring CVVHDF were studied. The media n filter survival time when using the postfilter ionized calcium algorithm was 3.4 days, with a survival probability of 46% (95% confidence interval [ CI], 17 to 71). Random-effects linear regression analysis did not show a si gnificant decline in blood-side urea clearance (P = 0.041) or creatinine cl earance (P = 0.308). Moreover, definite bleeding complications occurred wit h an incidence rate of 0.045/person-day on citrate anticoagulation (95% CI, 0.006 to 0.16), and occult bleeding occurred with an incidence rate of 0.0 91/person-day on citrate anticoagulation (95% CI, 0.03 to 0.23). Guiding re gional citrate anticoagulation through the use of posthemofilter ionized ca lcium levels is a safe and effective method of prolonging filter life durin g CVVHDF. (C) 2000 by the National Kidney Foundation, Inc.