Vitamin K for Perioperative Warfarin Management

NCT07515664 | Recruiting Phase 4 FDA Drug

• 2 other identifiers: HUM00264031K24HL179410
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

This is a feasibility study of uninterrupted warfarin with a one time dose of Vitamin K before a surgical procedure.

Conditions

Anticoagulant Therapy

Outcome Measures

Primary Outcomes (2)

• Feasibility of patient recruitment

  Percentage of recruited patients among those initially screened

  Within two weeks (from outreach to five days prior to procedure)

• INR reversal

  Percentage of enrolled patients with an INR less than or equal to 1.5 on morning of procedure

  Within 12 hours prior to procedure

Secondary Outcomes (9)

• Fidelity to intervention protocol

  12 day span from 2 days pre-operative through 10 days post-operative

• Fidelity to randomization

  24 hours (day of procedure)

• Cost per recruited patient

  12 day span from 2 days pre-operative through 10 days post-operative

• Patient acceptability

  10 days post procedure

• Clinical acceptability

  10 days post procedure

Study Arms (2)

Standard Warfarin Dosing with Vitamin K

EXPERIMENTAL

Patients will receive their standard warfarin dosing before, during, and after their procedure. This is in addition to a one time dose of oral vitamin K pre-procedure.

Drug: Vitamin K; Drug: Warfarin (standard without loading)

Loading Warfarin Dosing with Vitamin K

EXPERIMENTAL

Patients will receive their standard warfarin dosing before and during their procedure. On the night following the procedure, they will receive a one time loading dose of warfarin (twice their normal dose). Patients will then resume normal dosing of warfarin. This is in addition to a one time dose of oral vitamin K pre-procedure.

Drug: Vitamin K; Drug: Warfarin (standard with loading)

Interventions

Vitamin K DRUG

10 mg of oral vitamin K will be given approximately 36-48 hours before procedure.

Loading Warfarin Dosing with Vitamin K; Standard Warfarin Dosing with Vitamin K

Warfarin (standard without loading) DRUG

Patients receive their standard warfarin dosing without interruption.

Also known as: Coumadin

Standard Warfarin Dosing with Vitamin K

Warfarin (standard with loading) DRUG

Patients receive their standard warfarin dosing without interruption; patients also receive a one time loading dose (twice normal dose) of warfarin on the evening following their procedure.

Also known as: Coumadin

Loading Warfarin Dosing with Vitamin K

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Warfarin therapy for ≥3 months
• Use of home INR testing equipment
• Scheduled for a surgical procedure that requires INR ≤ 1.5 (typically achieved with warfarin interruption)
• INR ≤ 4 on day 7-10 prior to procedure

You may not qualify if:

• Surgical procedure does not require INR ≤1.5 (typically achieved with warfarin interruption)
• Surgical procedure with a high risk of bleeding or complications (urologic procedures, bronchoscopy, epidural injections, nerve blocks, spinal surgery)
• Warfarin therapy for \< 3 months
• Lack of English language proficiency
• Use of a Heartmate II or HVAD left ventricular assist device
• Recent thrombotic event (within 3 months)
• CHA2DS2-VASc score \>6
• INR \>4 on day 7-10 prior to procedure
• Hypersensitivity to any component of Vitamin K or simple syrup (used in the compounding process)

Sponsors & Collaborators

• University of Michigan: lead
• National Heart, Lung, and Blood Institute (NHLBI): collaborator

Study Sites (1)

Michigan Medicine

Ann Arbor, Michigan, 48109, United States

RECRUITING

MeSH Terms

Interventions

Vitamin K; Warfarin

Intervention Hierarchy (Ancestors)

Naphthoquinones; Naphthalenes; Polycyclic Aromatic Hydrocarbons; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Phytol; Diterpenes; Terpenes; Polycyclic Compounds; 4-Hydroxycoumarins; Coumarins; Benzopyrans; Pyrans; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring

Study Officials

• Geoffrey Barnes, MD

  University of Michigan

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Geoffrey Barnes, MD

CONTACT

734 936-4000; gbarnes@med.umich.edu

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor of Internal Medicine

Study Record Dates

• First Submitted: March 31, 2026
• First Posted: April 7, 2026
• Study Start: July 3, 2025
• Primary Completion: August 1, 2026
• Study Completion: August 1, 2026
• Last Updated: April 13, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)