Venous Thromboembolism
Conditions
Brief summary
Subcutaneous enoxaparin is currently the gold standard for VTE chemoprophylaxis. However, the efficacy of chemoprophylaxis with subcutaneous enoxaparin is affected by patient-level factors, thus, resulting in VTE events despite guideline-compliant prophylaxis. A population at particular risk is the growing number of patients who undergo autologous breast reconstruction. Direct oral anticoagulants (DOAC) might be a less invasive, yet, more efficacious mode of chemoprophylaxis in this patient population. Hence, the proposed work has the potential to cause a paradigm shift in chemoprophylaxis guidelines in a large population of patients undergoing plastic surgery.
Interventions
Patients will be assigned to the respective study groups postoperatively upon arrival in the post-anesthesia care unit. Hence, surgeons are blinded at the time of surgery as to study group assignment. Chemoprophylaxis will continue for the duration of the hospitalization.
Patients will be assigned to the respective study groups postoperatively upon arrival in the post-anesthesia care unit. Hence, surgeons are blinded at the time of surgery as to study group assignment. Chemoprophylaxis will continue for the duration of the hospitalization.
Sponsors
Stanford University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Caregiver)
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 89 Years
Healthy volunteers
No
Inclusion criteria
* Adult (\>18 years) women * Scheduled to undergo unilateral or bilateral microsurgical breast reconstruction with free abdominal flaps (i.e. muscle-sparing transverse rectus abdominis musculocutaneous \[TRAM\] and/or deep inferior epigastric artery perforator \[DIEP\]) flap) * Caprini score of 6 or greater. * Ability to understand and the willingness to sign a written informed consent document.
Exclusion criteria
* Contraindication to the use of apixaban or enoxaparin * Active bleeding * History of bleeding disorder * History of coagulopathy * History of heparin-induced thrombocytopenia * History of liver disease * History of renal disease (creatinine clearance \<30 mL/min; serum creatinine \>1.6 mg/dL) * Major neurosurgical intervention (brain/spine) within the past 90 days * Ophthalmologic procedure within the past 90 days * Uncontrolled hypertension * History of alcohol and/or substance abuse * Need for therapeutic anticoagulation * Pregnant or Nursing
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Apixaban vs. Enoxaparin - Number of Participants With Bleeding Events | 90-day events | To examine the rate of bleeding events in patients receiving oral apixaban versus subcutaneous enoxaparin following microsurgical breast reconstruction |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Apixaban vs. Enoxaparin - Number of Participants With Venous Thromboembolism (VTE) Events | 90 days | To examine the rate of VTE events in patients receiving oral apixaban versus subcutaneous enoxaparin following microsurgical breast reconstruction |
Countries
United States
Participant flow
Pre-assignment details
82 participants signed informed consent; 76 were allocated to treatment.
Participants by arm
| Arm | Count |
|---|---|
| Apixaban Patients assigned to this group will receive Apixaban 2.5 mg PO BID starting 12 hours after completing skin closure. | 37 |
| Enoxaparin Patients assigned to this group will receive Enoxaparin 40 mg SC QD starting 12 hours after completing skin closure. | 39 |
| Total | 76 |
Baseline characteristics
| Characteristic | Enoxaparin | Total | Apixaban |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 6 Participants | 9 Participants | 3 Participants |
| Age, Categorical Between 18 and 65 years | 33 Participants | 67 Participants | 34 Participants |
| Age, Continuous | 53 years STANDARD_DEVIATION 11 | 53 years STANDARD_DEVIATION 0 | 53 years STANDARD_DEVIATION 10 |
| Race and Ethnicity Not Collected | — | 0 Participants | — |
| Region of Enrollment United States | 39 Participants | 76 Participants | 37 Participants |
| Sex: Female, Male Female | 39 Participants | 76 Participants | 37 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 37 | 0 / 39 |
| other Total, other adverse events | 6 / 37 | 5 / 39 |
| serious Total, serious adverse events | 1 / 37 | 1 / 39 |
Outcome results
Primary
Apixaban vs. Enoxaparin - Number of Participants With Bleeding Events
To examine the rate of bleeding events in patients receiving oral apixaban versus subcutaneous enoxaparin following microsurgical breast reconstruction
Time frame: 90-day events
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Apixaban | Apixaban vs. Enoxaparin - Number of Participants With Bleeding Events | 1 Participants |
| Enoxaparin | Apixaban vs. Enoxaparin - Number of Participants With Bleeding Events | 1 Participants |
Secondary
Apixaban vs. Enoxaparin - Number of Participants With Venous Thromboembolism (VTE) Events
To examine the rate of VTE events in patients receiving oral apixaban versus subcutaneous enoxaparin following microsurgical breast reconstruction
Time frame: 90 days
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Apixaban | Apixaban vs. Enoxaparin - Number of Participants With Venous Thromboembolism (VTE) Events | 6 Participants |
| Enoxaparin | Apixaban vs. Enoxaparin - Number of Participants With Venous Thromboembolism (VTE) Events | 5 Participants |