Microsurgical Breast Reconstruction & VTE

Study Overview
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Brief Summary
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Venous thromboembolism (VTE) encompasses pulmonary embolism (PE) and deep venous thrombosis (DVT) and continues to be a major patient safety issue after reconstructive plastic surgery. Significant morbidity and mortality is associated with VTE events. This disease entity represents the most common cause of preventable in-hospital death as evidenced by over 100,000 annual VTE-related deaths in the U.S. The associated economic burden is substantial, with annual costs to the U.S. healthcare system in excess of $7 billion. Cancer patients have been identified as a particularly vulnerable patient population. Of these, breast cancer patients represent the largest group treated by plastic surgeons. An increasing number of breast reconstructions are performed in the U.S. with a documented 35% increase in the annual number of breast reconstructions since 2000. Over 106,000 breast reconstructions were performed in 2015 alone. Of all reconstructive modalities, autologous breast reconstruction using abdominal flaps is associated with the highest risk for VTE. We believe that a key element rendering these patients susceptible to postoperative VTE is inadequate duration of chemoprophylaxis. This is supported by the observation that VTE risk remains elevated for up to 12 weeks postoperatively. We hypothesize that lower extremity deep venous system stasis is a procedure-specific key contributing factor to postoperative VTE risk. This study examines the duration of postoperative lower extremity venous stasis to identify patients who might benefit from extended chemoprophylaxis. We will use Duplex imaging technology to examine the lower extremity deep venous system preoperatively, on postoperative day 1, and on the day of discharge to determine if patients display radiographic evidence of lower extremity venous stasis at the time of hospital discharge. A better understanding of pathophysiologic mechanisms that contribute to the development of VTE as well as surgical means that reduce VTE risk factors have the potential to optimize VTE prophylaxis, thus, favorably impacting clinical outcome in a large patient population.

Official Title
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Microsurgical Breast Reconstruction - Identifying Procedure-Specific Risk Factors for Venous Thromboembolism

Conditions
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Breast Reconstruction, Venous Thromboembolism

Intervention / Treatment
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* Diagnostic Test: Duplex ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: see study population description Exclusion Criteria: Superficial inferior epigastric artery flaps Donor-sites other than the abdomen Chronic obstructive pulmonary disease (COPD) Liver disease.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 1<br>Patients undergo primary fascial closure of abdominal donor-site | Diagnostic Test: Duplex ultrasound<br>* Duplex ultrasound of lower extremity venous system<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vessel diameter (in cm) |  | 1 Day of discharge | 
| Cross-sectional area (in cm^2) |  | 1 Day of discharge | 
| Flow velocity (in cm/sec) |  | 1 Day of discharge | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 90-day VTE event |  | 90-day | 
| Abdominal hernia/bulge rate at 1 year postop |  | 1 year |