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Published on: September 9, 2012
Reversal of Warfarin-Associated Major Hemorrhage: Activated Prothrombin Complex Concentrate versus 4-Factor
Gary D Peksa1,2, Robert K Mokszycki3, Megan A Rech4
1Department of Pharmacy, Rush University Medical Center, Chicago, Illinois, United States.
Background:
Warfarin-associated major hemorrhage is frequently treated with prothrombin complex concentrates to correct international normalized ratio (INR).
Objective:
This article aims to investigate the efficacy of activated prothrombin complex concentrate (aPCC) versus 4-factor prothrombin complex concentrate (4PCC) for vitamin K antagonist reversal in patients with warfarin-associated major hemorrhage.
Materials And Methods:
This was a multicenter, retrospective cohort study. Patients included were age ≥ 18 years with pretreatment INR of > 1.5. Exclusion criteria were patients treated for urgent procedures without hemorrhage, treated but not taking warfarin, unavailable INR values, and pregnant patients. Patients were stratified into two groups: aPCC or 4PCC. The primary outcome was achievement of INR ≤ 1.5 at the posttreatment INR sampling. Secondary outcomes focused on thrombotic events and mortality.
Results:
Of 342 patients, 237 patients received aPCC and 105 patients received 4PCC. After 1:1 propensity score matching, 86 patients remained in each group. In the matched cohort, the proportion of patients who achieved target INR ≤ 1.5 was greater with 4PCC (aPCC = 61 [70.9%] vs. 4PCC = 76 [88.4%]; 95% confidence interval [CI] -29.2% to -5.7%) and groups had comparable in-hospital thrombotic events and mortality. In the unmatched cohort, achievement of target INR ≤ 1.5 was greater with 4PCC (aPCC = 151 [63.7%] vs. 4PCC = 92 [87.6%]; 95% CI -32.7% to -15.1%).
Conclusion:
In the treatment of warfarin-associated major hemorrhage, 4PCC compared with aPCC was associated with greater achievement of INR ≤ 1.5 with comparable thrombotic events and mortality. Further controlled studies are needed to confirm these findings and determine the optimal dosing strategy that maximizes efficacy and safety.
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