Minimization of Bleeding Related Adverse Drug Events in Plastic & Reconstructive Surgery

Study Overview
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Brief Summary
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Plastic and reconstructive surgeons consistently create large, raw surfaces as part of their operative procedures. Thus, plastic & reconstructive surgery patients are among those at highest risk for anticoagulant-associated bleeding adverse drug events (ADEs). This study seeks to optimize both the safety and effectiveness of post-operative enoxaparin by comparing aFXa levels, bleeding events, and VTE events among plastic & reconstructive surgery patients randomized to receive two different enoxaparin dose regimens.

Detailed Description
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Plastic and reconstructive surgeons consistently create large, raw surfaces as part of their operative procedures. Thus, plastic & reconstructive surgery patients are among those at highest risk for anticoagulant-associated bleeding adverse drug events (ADEs). Our preliminary data has shown that a fixed, or one size fits all dose of enoxaparin, an anticoagulant, can allow a high proportion of patients to have appropriately thinned blood, measured by anti-Factor Xa (aFXa) levels. Patients with adequate aFXa levels are known to have significantly decreased venous thromboembolism risk (VTE), which is desirable. However, 30% of patients who receive fixed dose enoxaparin have blood that is too thin. Patients who are over-anticoagulated are significantly more likely to have ADEs including bleeding requiring return to the operating room, need for blood transfusion, or death. The optimal way to dose enoxaparin to minimize ADEs remains unknown. This study seeks to optimize both the safety and effectiveness of post-operative enoxaparin by comparing aFXa levels, bleeding events, and VTE events among plastic & reconstructive surgery patients randomized to receive two different enoxaparin dose regimens.

Official Title
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Minimization of Bleeding Related Adverse Drug Events in Plastic & Reconstructive Surgery Patients Randomized to Different Postoperative Anticoagulant Regimens

Conditions
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Venous Thromboembolism, Deep Venous Thrombosis, Pulmonary Embolus, Reconstructive Surgery

Intervention / Treatment
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* Drug: Fixed dose
* Drug: Variable dose


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: receiving plastic and reconstructive surgery under general anesthesis Expected post-operative stay of 2 days or more Exclusion Criteria: Contraindication to use of enoxaparin intracranial bleeding/stroke Hematoma or bleeding disorder Heparin-induced thrmbocytopenia positive Creatinine clearance less than or equal to 30 mL/min Serum creatinine greater than 1.6 mg/dL epidural anesthesia patients placed on non-enoxaparin chemoprophylaxis regimens gross weight exceeding 150kg

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Patients will be randomized into one of two groups (enoxaparin 40mg twice daily or enoxaparin 0.5mg/kg twice daily, rounded to the nearest milligram).
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Fixed Dose<br>Participants will receive 40 mg enoxaparin twice daily | Drug: Fixed dose<br>* Participants will receive 40 mg enoxaparin twice daily<br>|
| Experimental: Variable Dose<br>Participants will receive 0.5mg/kg enoxaparin twice daily | Drug: Variable dose<br>* Participants will receive 0.5mg/kg enoxaparin twice daily<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Avoidance of Under-anticoagulation (Peak aFXa <0.2 IU/mL) | Avoidance of under-anticoagulation (peak aFXa <0.2 IU/mL) | Four hours following third enoxaparin dose | 
| Avoidance of Over-anticoagulation (Peak aFXa >0.4 IU/mL) | Avoidance of over-anticoagulation (peak aFXa >0.4 IU/mL) | Four hours following third enoxaparin dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants With Venous Thromboembolism Events | Any symptomatic venous thromboembolism events, including deep venous thrombosis or pulmonary embolus occurring within 90 days of surgery | 90 days | 
| Percentage of Patients With Bleeding Events | Bleeding events requiring alteration in the course of care within 90 days of surgery | 90 days |