The effectiveness and safety of fixed low-dose prothrombin complex concentrates in patients requiring urgent reversal of warfarin.
BACKGROUND
A rapid method of reversal is required for patients on warfarin who suffer acute bleeding or require emergency surgery. Prothrombin complex concentrates (PCCs) have recently been recommended by the Canadian Blood Services for use at a fixed low dose of 1000 IU of Factor (F)IX activity. The main goal of this study was to investigate both the effectiveness and the safety of fixed low-dose PCCs.


METHODS
We retrospectively reviewed charts from 103 patients who received PCCs for reversal of warfarin therapy.


RESULTS
A total of 103 patients were treated with PCC at a single fixed dose of 1000 IU of F IX activity. Fifty patients (48.5%) had a final international normalized ratio (INR) response of not more than 1.5 and an additional 45 patients (43.7%) had a final INR response between 1.6 and 2.0. However, 86 patients (83.5%) had an excellent clinical response consisting of control of bleeding without the requirement of additional measures. In a multivariable model, patients who received fresh-frozen plasma and patients who were given doses greater than 1000 IU of PCC were both identified as predictors of a poor clinical response (odds ratio [OR] 3.48, 95% confidence interval [CI] 0.76-15.89, p = 0.11; and OR 10.8, 95% CI 2.08-56.28, 95% CI, p = 0.005, respectively). There were five adverse events up to 30 days after PCC use.


CONCLUSIONS
At a fixed dose of 1000 IU of F IX activity, PCC seems to be effective and safe but randomized controlled trials, specifically examining different doses of PCC, are required to confirm the above observations.
Departments of Medicine and Epidemiology, Jewish General Hospital, McGill University, Montreal, Quebec, Canada.
Cindy
C
Varga
Sultan
S
Al-Touri
Stella
S
Papadoukakis
Stephen
S
Caplan
Susan
S
Kahn
Mark
M
Blostein
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000037:antagonists & inhibitors*; D001779:Blood Coagulation Factors / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D019934:International Normalized Ratio; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014859:Warfarin / Q000037:antagonists & inhibitors*
D000925:Anticoagulants; D001779:Blood Coagulation Factors; C025667:prothrombin complex concentrates; D014859:Warfarin