An audit of the role of vitamin K in the reversal of International Normalised Ratio (INR) in patients undergoing surgery for hip fracture

Ann R Coll Surg Engl. 2010 Sep;92(6):473-6. doi: 10.1308/003588410X12664192075774. Epub 2010 May 19.


Introduction: The objective of this prospective audit was to compare two methods of anticoagulation reversal in the pre-operative period for hip fracture patients.

Patients and methods: In the first part of the audit, our current practice was analysed. Data relating to the number of days from admission to surgery and the reasons for delay to surgery were collected. Also, data concerning common reasons for which the patients were started on warfarin and the time required for INR to drop to 1.5 or below were collected. In the second part of the audit, 45 patients with INR above 1.5 were given a single dose of vitamin K (1 mg i.v.) in addition to stopping warfarin.

Results: The mean difference in the time for INR < 1.5 in the two groups was 2 days (52 h; P < 0.05). The mean difference in wait for surgery since admission between the two groups was 4 days (91 h; P < 0.05). There was no significant difference between the two groups as regards the average number of co-morbidities in the patient groups.

Conclusions: A single 1 mg intravenous dose of vitamin K significantly reduces the time for the reversal of INR and the pre-operative delay to surgery, in patients on long-term warfarin. We conclude that 1 mg of intravenous vitamin K on admission is a safe and effective treatment to avoid delay in the treatment in this group of patients.

Publication types

  • Clinical Trial
  • Multicenter Study

MeSH terms

  • Aged
  • Anticoagulants / antagonists & inhibitors*
  • Antifibrinolytic Agents / pharmacology*
  • Blood Coagulation / drug effects
  • Female
  • Femoral Neck Fractures / surgery*
  • Fracture Fixation / methods
  • Humans
  • International Normalized Ratio
  • Male
  • Medical Audit
  • Practice Guidelines as Topic
  • Preoperative Care / methods
  • Preoperative Period
  • Vitamin K / pharmacology*
  • Warfarin / antagonists & inhibitors


  • Anticoagulants
  • Antifibrinolytic Agents
  • Vitamin K
  • Warfarin