Direct oral anticoagulant reversal: how, when and issues faced

Partial warfarin reversal prior to hip fracture surgical intervention in geriatric trauma patients effects on blood loss and transfusions

BACKGROUND

Warfarin reversal is typically sought prior to surgery for geriatric hip fractures; however, patients often proceed to surgery with partial warfarin reversal. The effect of partial reversal (defined as having an international normalized ratio [INR] > 1.5) remains unclear.

METHODS

This was a retrospective cohort study. Geriatric patients (≥65 y/o) admitted to six level I trauma centers from 01/2014-01/2018 with isolated hip fractures requiring surgery who were taking warfarin pre-injury were included. Warfarin reversal methods included: vitamin K, factor VIIa, (a)PCC, fresh frozen plasma (FFP), and the "wait and watch" method. An INR of ≤ 1.5 defined complete reversal. The primary outcome was the volume of blood loss during surgery; other outcomes included packed red blood cell (pRBC) and FFP transfusions, and time to surgery.

RESULTS

There were 135 patients, 44% partially reversed and 56% completely reversed. The median volume of blood loss was 100 mL for both those completely and partially reversed, p = 0.72. There was no difference in the proportion of patients with blood loss by study arm, 95% vs. 95%, p > 0.99. Twenty-five percent of those completely reversed and 39% of those partially reversed had pRBCs transfused, p = 0.08. Of those completely reversed 5% received an FFP transfusion compared to 14% of those partially reversed, p = 0.09. There were no statistically significant differences observed for the volume of pRBC or FFP transfused, or for time to surgery.

CONCLUSIONS

Partial reversal may be safe for blood loss and blood product transfusions for geriatric patients with isolated hip fractures. Complete warfarin reversal may not be necessary prior to hip fracture surgery, especially for mildly elevated INRs.

Is anticoagulation reversal necessary prior to surgical treatment of geriatric hip fractures?

OBJECTIVE

Hip fracture surgery in geriatric patients on anticoagulants may increase the risk for blood loss. Anticoagulation reversal may lower these risks; however, data on blood loss and transfusions are limited. The study purpose was to compare outcomes between hip fracture patients 1) not on anticoagulants 2) whose anticoagulants were reversed, and 3) whose anticoagulants were not reversed.

METHODS

This four-year retrospective cohort study at six Level 1 Trauma Centers enrolled geriatric patients (≥65) with isolated hip fractures. The primary outcome was total hospital blood loss (ml). Secondary outcomes: hospital length of stay (HLOS) and volume of packed red blood cells (pRBC) transfusions (ml). Statistical analyses included: Fisher's, chi-squared, Kruskal-Wallis, linear mixed-effect and logistic regression. Bonferroni adjusted alpha = 0.025.

RESULTS

Of the 459 patients, 189 (41%) were not on anticoagulants, 186 (41%) were reversed, and 84 (18%) were not reversed. The LS mean (SE) blood loss was 134 ml (12) for not reversed patients and 159 (17) for reversed patients; no significant difference compared to those not on anticoagulants [138 (12)], p-diff = 0.14 and 0.83, respectively. The LS mean (SE) HLOS was significantly longer for the reversed patients, 7.7 (0.4) days, when compared to those not on anticoagulants, 6.8 (0.4), p = 0.02, and when compared to those not reversed, 6.3 (0.6), p = 0.01. There was no significant difference in pRBC transfusions.

CONCLUSION

Not reversing anticoagulants for geriatric hip fractures was not associated with increased volume of blood loss or transfusions when compared to those reversed. Delayed surgery for anticoagulant reversal may be unnecessary and contributing to an increased HLOS.