NCT02704052

Real-time Anti-Factor Xa Measurements in Surgical Patients to Examine Enoxaparin Metabolism and Optimize Enoxaparin Dose

• Status: Completed
• Phase: EARLY_Phase 1
• Study type: Interventional
• Enrollment: 116 (actual)
• Sponsor: University of Utah · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

Venous thromboembolism (VTE) encompasses deep venous thrombosis and pulmonary embolus, and is the proximate cause of death in over 100,000 hospitalized patients per year. This project will critically examine the pharmacokinetics of prophylactic doses of enoxaparin in surgical patients, and will evaluate how alteration of enoxaparin dose magnitude and frequency affects peak and trough aFXa levels as well as risk for re-operative hematoma. If subtherapeutic aFXa levels are observed, the study will design, implement and test a clinical protocol to optimize post-operative aFXa levels. Although not an explicit Aim, this study will also provide important preliminary data on VTE rates in surgical patients with in range and out of range aFXa levels.

Detailed description

Venous thromboembolism (VTE) encompasses deep venous thrombosis and pulmonary embolus, and is the proximate cause of death in over 100,000 hospitalized patients per year. To put this in better context, VTE kills more people each year than the annual morbidity from motor vehicle crashes and breast cancer combined. Surgeons commonly provide enoxaparin, a low molecular weight heparin, for VTE prophylaxis. Enoxaparin's activity is quantified by anti-Factor Xa (aFXa) levels. Studies of enoxaparin metabolism in patients with traumatic injury, thermal injury, or those undergoing reconstructive surgery have shown that standard dosing can result in inadequate aFXa levels, likely from the hypermetabolic state associated with significant injury. Small studies have associated subtherapeutic aFXa levels with increased risk for life or limb-threatening VTE events. Prior work from has shown that 2-10% of highest risk surgical patients have a VTE event despite enoxaparin prophylaxis. The investigators believe that surgical patients would benefit from an individualized dosing regimen for enoxaparin prophylaxis and that individualized dosing will decrease observed rates of life or limb-threatening post-operative VTE events. This project will critically examine the pharmacokinetics of prophylactic doses of enoxaparin in surgical patients, and will evaluate how alteration of enoxaparin dose magnitude and frequency affects peak and trough aFXa levels as well as risk for re-operative hematoma. If subtherapeutic aFXa levels are observed, the study will design, implement and test a clinical protocol to optimize post-operative aFXa levels. Although not an explicit Aim, this study will also provide important preliminary data on VTE rates in surgical patients with in range and out of range aFXa levels.

Conditions

• Deep Venous Thrombosis
• Pulmonary Embolus
• Venous Thromboembolism

Interventions

Type	Name	Description
DRUG	Real time enoxaparin dose adjustment	Patients will have steady state peak and trough anti-Xa levels drawn after their third enoxaparin dose. Patients with out of range peak anti-Xa levels will receive real time enoxaparin dose adjustment followed by repeat peak and trough anti-Xa levels.
DRUG	Standard enoxaparin dose	Patients will be placed on enoxaparin prophylaxis per their surgeon's discretion.

Timeline

• Start date: 2016-03-01
• Primary completion: 2018-07-01
• Completion: 2018-10-01
• First posted: 2016-03-09
• Last updated: 2019-05-24

Locations

1 site across 1 country: United States