Doppler Ultrasound Imaging of Plastic Surgery Patients for Deep Venous Thrombosis Detection: A Prospective Controlled Study
Doppler Ultrasound Imaging of Plastic Surgery Patients for Deep Venous Thrombosis Detection: A Prospective Controlled Study.
Goals/Purpose:
Venous thromboembolism is a well-known and serious risk of surgery. In an attempt to reduce the frequency of this postoperative complication, many plastic surgeons today elect to anticoagulate patients deemed to be at higher risk.1 The efficacy and ethics of this treatment have been challenged.2 Moreover, prophylactic anticoagulation poses additional serious risks of its own, including increased bleeding and wound hematomas.2 Although the risk of thromboembolism may be higher in patients with known risk factors,1 a substantial proportion of postoperative thromboembolic events occur in patients with low or moderate risk scores.1,2 Doppler ultrasound imaging represents a sensitive, direct, and noninvasive method to screen for the presence of venous thromboses.3 This pilot study was undertaken to determine its feasibility in the setting of outpatient plastic surgery. Doppler ultrasound imaging as a screening tool for elective plastic surgery patients has not been previously reported.
Methods/Technique:
Twenty-five consecutive consenting patients undergoing outpatient elective plastic surgery under total intravenous anesthesia were investigated using Doppler ultrasound scans preoperatively, on the first day after surgery (Figs. 1 and 2), and approximately 1 week after surgery. Common operations included liposuction, abdominoplasty, facelifts, and cosmetic breast surgery. The Terason t3200 Ultrasound Vascular series (Terason Ultrasound, Burlington, Mass.) was used to image the deep veins of both lower extremities. The veins evaluated with this imaging technique consisted of the common femoral, greater saphenous, superficial femoral, popliteal, and posterior tibial veins. Both color Doppler flow and 2-dimensional compression tests (Duplex scans) were administered. Twenty-five nonoperative control patients were also evaluated at the same time intervals.
Clinical measures to reduce the risk of venous thrombosis included: (1) spontaneous breathing without muscle relaxants, (2) no prone positioning in surgery, (4) sequential compression devices, (4) movement of the lower extremities during surgery, and (5) outpatient surgery with early ambulation.2 No patient received anticoagulation.
Results/Complications:
There was no evidence of thrombosis on any of the scans in either treatment or control patients. There was also no clinical evidence of venous thrombosis in these patients. No patient experienced excessive bleeding or a hematoma.
Conclusion:
Doppler ultrasound imaging offers a safe, sensitive method to screen for the presence of deep venous thrombi in the early postoperative period. It is well-tolerated by patients who understand the importance of the test. Subclinical blood clots may be detected. This imaging technique offers a rational alternative to anticoagulation and avoids the unwanted and sometimes dangerous side effects of anticoagulation in postsurgical patients. Risk stratification is unnecessary. This study introduces a powerful new tool for plastic surgeons to improve patient safety. Additional study is needed to assess a larger number of patients and this study is presently underway.
References:
1. Pannucci CJ, Dreszer G, Fisher Wachtman C, et al. Postoperative enoxaparin prevents symptomatic venous thromboembolism in high-risk plastic surgery patients. Plast Reconstr Surg. 2011;128:1093-1103.
2. Swanson E. Chemoprophylaxis for venous thromboembolism prevention: Concerns regarding efficacy and ethics. Plast Reconstr Surg. – Global Open. 2013;1:e23. doi: 10.1097/GOX.0b013e318299fa26.
3. Zierler BK. Diagnosis of venous thromboembolism. Circulation 2004;109:I-9-I-14.
Fig. 1: Color Doppler ultrasonic scan in a 60-year-old woman 24 hours after a lower body lift and other cosmetic procedures. The right common femoral vein is imaged. The blue color indicates unobstructed blood flow returning to the heart. The right femoral artery is visible on the left, with blood flowing primarily away from the heart, colored red.
Fig. 2: Same patient. The right common femoral vein is fully compressed by manual depression of the ultrasound probe, revealing that there is no thrombus inhibiting compression. Blood flow is still visible in the right femoral artery, which remains uncompressed.