Interruption of long-term warfarin is not necessary in patients undergoing total hip arthroplasty

The management of anticoagulation in patients undergoing arthroplasty remains a challenge. Guidelines for perioperative management of long-term warfarin recommend discontinuation of warfarin preoperatively in low risk patients. We hypothesised that patients who had their warfarin continued during the perioperative period would have shorter hospital stay and no significant increase risk of surgical complications compared to patients who had their warfarin interrupted.

This was a retrospective review of 20 consecutive patients receiving long-term warfarin who underwent total hip replacement without stopping warfarin. As a control group, we collected same data from 20 age and gender matched patients also on long term warfarin but their warfarin was stopped prior to surgery and restarted postoperatively.

There was no significant difference in age, BMI or comorbidities between the 2 groups. There was a statistically significant difference between the two groups in postoperative INR (P < 0.0001) levels. The mean drop in Hb postoperatively was 25.95 g/L in the warfarin group and 35.7 g/L in the control group, which was statistically significant (P = 0.0066). Hospital stay was statistically significant with shorted stay observed in the warfarin group (P = 0.0447). The odds ratio for developing a postoperative complication was 1.5882 which was not statistically significant (P = 0.6346).

Our results support the hypothesis that it is safe to continue warfarin in patients on long term anticoagulation undergoing total hip replacement. Continuation of warfarin was associated with significantly shorter hospital stay and less INR fluctuations. There was no significant increase in the risk of complications or blood transfusion.