Thrombelastography Based Dosing of Enoxaparin for Thromboprophylaxis: a Prospective Randomized Trial
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 185
- Locations
- 3
- Primary Endpoint
- Development of Deep Vein Thrombosis (DVT)
Study Overview
Brief Summary
The risk of developing a blood clot occurs in up to 60% of all critical care patients. Many times enoxaparin (or Lovenox®) is given to patients who are at a higher risk of developing clots in their legs or lungs. Recent data suggest that a standard dose of Lovenox may not fully prevent the development of these clots especially in critically ill or obese patients. Routine enoxaparin dosing can also result in bleeding complications. Thrombelastography (TEG®) can be used to measure how blood clots. The purposes of this study are:
- to learn if the TEG® can better guide physicians in prescribing an effective dose of Lovenox compared to standard doses recommended by the drug company in preventing blood clots from developing in the legs and lungs, and
- to compare the development of blood clots in patients receiving the standard dose of enoxaparin compared to patients receiving a TEG® guided dose of enoxaparin.
- to determine if TEG guided dosing results in decreased bleeding complications compared to standard dosing.
Detailed Description
Hypothesis:
Enoxaparin dosed to maintain a TEG® ΔR greater than 1.0 minute will decrease the incidence of DVT compared to standard dosing.
Initiation of enoxaparin thromboprophylaxis will be done by the treatment team. Once enrolled, the subject will be randomized to continue receiving standard dose enoxaparin (30 mg twice daily) or variable TEG® guided enoxaparin dosing. The treatment team and the subject will be blinded regarding the arm in which the patient is enrolled. Patient characteristics: age, gender, body mass index (BMI), comorbidities, Acute Physiology and Chronic Health Evaluation II score (APACHE II), injuries, and operations will be collected. As part of standard protocol in the ICU, all patients will undergo weekly ultrasound duplex examination of the lower extremities for presence of deep venous thrombosis.
A baseline TEG® will be completed on each patient when they are enrolled in the study. The blood will be drawn between four and six hours after the morning dose is administered, corresponding to maximum tissue levels of enoxaparin. TEG® assays will be run in duplicate for each patient, with and without heparinase, which negates the effects of enoxaparin in the assay.
Those patients randomized to the control arm of the study will have TEG® performed at baseline and daily for one week, then twice weekly. The twice weekly TEG® assays will be done until the patient is discharged from inpatient care or enoxaparin is discontinued by the treatment team. No adjustments will be made to their enoxaparin dosing.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Prevention
- Masking
- Double (Participant, Care Provider)
Eligibility Criteria
- Ages
- 15 Years to — (Child, Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Inpatient initiated on enoxaparin thromboprophylaxis
- •Age greater than 15 years
Exclusion Criteria
- •Unable to obtain consent from patient or ARR
- •Presence of: intracranial hemorrhage, brain injury
- •Receiving therapeutic dose enoxaparin
- •Receiving other forms of anticoagulation
- •Receiving non-standard dosing regimen of enoxaparin
Arms & Interventions
Enoxaparin 30 mg BID
standard dose enoxaparin thromboprophylaxis (30 mg twice daily)
Intervention: Enoxaparin 30 mg BID (Drug)
Enoxaparin dose adjusted based on TEG
enoxaparin dose modified based on TEG results
Intervention: Enoxaparin dose adjusted Lovenox based on TEG (Drug)
Outcomes
Primary Outcomes
Development of Deep Vein Thrombosis (DVT)
Time Frame: Through study completion, assessed up to 120 days post randomization
An ultrasound duplex will be completed at least one time after randomization to determine if the subject has developed a DVT.
Secondary Outcomes
- Incidence of Bleeding Complications(Through study completion, assessed up to 120 days post randomization)
Investigators
Martin A Schreiber, MD
Professor & Chief of Trauma
Oregon Health and Science University