Twice Daily Enoxaparin Prophylaxis in Reconstructive Surgery Patients

Summary

Blood clots that form in the extremities (deep venous thrombosis) and lungs (pulmonary embolus) are feared complications of reconstructive surgery. One in ten patients with symptomatic pulmonary embolus will be dead in 60 minutes. Patients with deep venous thrombosis can develop the post-thrombotic syndrome, known to be a major driver of poor quality of life. These phenomena, broadly known as venous thromboembolism (VTE), have substantial downstream ramifications, and the US Surgeon General and the American Society of Plastic Surgeons (ASPS), among others, have underscored the importance of VTE prevention in surgical patients. Reconstructive surgery, most commonly performed to fix traumatic injuries or defects after cancer excision, often involves borrowing tissue from adjacent or distant areas on the body; reconstructive surgery patients can routinely have surgical injury involving 20% or more of their total body surface area. Injury and resultant inflammation are known to increase metabolism of certain drugs, including those used to prevent VTE after surgery.

Enoxaparin is a blood-thinning medication that decreases likelihood of blood clot formation. Previous research has shown that reconstructive surgery patients who are given enoxaparin after surgery are less likely to develop VTE. However, despite receiving of a standard dose of enoxaparin, many patients still develop this life-threatening complication. The investigators believe that patients metabolize enoxaparin differently based on the degree of surgical injury created during reconstruction, and seek to critically examine enoxaparin metabolism in reconstructive surgery patients. The proposed research will evaluate how enoxaparin affects the blood based on standard, ASPS-recommended dosing after reconstructive surgeries; the investigators will also examine whether the extent of surgical injury alters metabolism as well. Enoxaparin effectiveness will be tracked using anti-Factor Xa (aFXa) levels. If subtherapeutic aFXa levels are observed, the study will also design, implement and test a clinical enoxaparin dose-adjustment protocol to achieve appropriate post-operative aFXa levels. Further research based on these data will examine reduction in VTE risk when aFXa-driven enoxaparin dosing is used.

Conditions

• Venous Thromboembolism
• Deep Venous Thrombosis
• Pulmonary Embolus

Interventions

DRUG

Twice daily enoxaparin prophylaxis

Patients will have peak and trough steady state anti-Xa levels drawn. For patients with out of range peak levels, real time enoxaparin dose adjustment using a clinical protocol will be performed. Repeat steady state levels will be checked.

DRUG

Real time dose adjustment

Patients will have peak and trough steady state anti-Xa levels drawn. For patients with out of range peak levels, real time enoxaparin dose adjustment using a clinical protocol will be performed. Repeat steady state levels will be checked.

Sponsors & Collaborators

• Agency for Healthcare Research and Quality (AHRQ)

  collaborator FED

• University of Utah

  lead OTHER

Principal Investigators

• Christopher Pannucci, MD MS · University of Utah

Study Design

Allocation

NON_RANDOMIZED

Purpose

PREVENTION

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2016-03-31

Primary Completion

2017-06-23

Completion

2017-12-06

FDA Drug

Yes

Countries

• United States

Study Locations