Pre-Operative Direct Oral Anticoagulant Level Measurement Reduces Time to Surgery in Hip Fracture Patients

Stephanie Su-Yin P'ng; Yue Wern Teh; Sophie Reynolds; Glenn Boardman; Christopher W Jones; Hannah Seymour

doi:10.1177/21514593221142187

Pre-Operative Direct Oral Anticoagulant Level Measurement Reduces Time to Surgery in Hip Fracture Patients

Geriatr Orthop Surg Rehabil. 2024 Dec 9:15:21514593221142187. doi: 10.1177/21514593221142187. eCollection 2024.

Authors

Stephanie Su-Yin P'ng^{1

2}, Yue Wern Teh², Sophie Reynolds³, Glenn Boardman⁴, Christopher W Jones^{2

5

6}, Hannah Seymour²

Affiliations

¹ Pathwest Western Diagnostic Laboratory, Fiona Stanley Hospital, Murdoch, WA, Australia.
² Fiona Stanley Hospital, Murdoch, WA, Australia.
³ Royal Perth Hospital, Perth, WA, Australia.
⁴ South Metropolitan Health Service, Palmyra, WA, Australia.
⁵ The Orthopaedic Research Foundation of Western Australia, Fiona Stanley Hospital, Perth, WA, Australia.
⁶ Curtin University, Perth, WA, Australia.

Abstract

Introduction: The optimal management of patients taking DOAC medications in the perioperative trauma setting is based on limited evidence. Current guidelines recommend withholding DOAC medications 48-72 hours pre-operatively. The objective of this trial was to determine the utility of measuring DOAC levels prior to surgery, evaluate the safety of a cut-off level of <50 ng/mL and to compare the outcomes with time parameters.

Materials and methods: We performed a cohort study of patients aged 50 years and older admitted with a hip fracture who underwent surgery between January 12 017 and December 31 2019. Primary outcome was time to surgery (TTS) in hours. Secondary outcomes include inpatient transfusion and thromboembolism rates and 30-day mortality.

Results: 1579 patients underwent operative management of their hip fracture. The mean TTS in the DOAC group was 33.0 hours. This was significantly longer when compared to patients not on anticoagulation whose mean TTS was 24.4hours (95% CI -13.78: -8.71, P value <.05). It was also significantly higher than patients on warfarin whose mean TTS was 26.4hours (95% CI -12.41: -4.18, P value <.05). There was no significant difference in the transfusion rate and 30-day mortality between the groups (X² = 2.086, df = 2, P value = .352)]. There was no significant difference in transfusion rates and 30-day mortality between the patients with a DOAC level <50 ng/mL compared with the patients not on any anticoagulation. There was no significant difference in 30-day mortality or transfusion rates between those patients on a DOAC operated within 48 hours compared with those operated after 48 hours (P value = .67).

Discussion and conclusion: DOAC therapy delays surgery for patients with a hip fracture. Using a DOAC level <50 ng/mL is a safe level to proceed with surgery and reduces the TTS compared to following current guidelines. If DOAC levels are not available the data still supports operation at 48 hours.

Keywords: anticoagulation; direct oral anticoagulant; hip fracture.