Extended Venous Thromboembolism Chemoprophylaxis following Microsurgical Breast Reconstruction: Analysis of Trends in Postoperative Anticoagulation

Abstract

Background: Microsurgical breast reconstruction following mastectomy represents a high-risk patient group for venous thromboembolism (VTE), but there is limited consensus on postoperative prophylaxis duration. The aim of this study was to characterize the risk of VTE after microsurgical breast reconstruction, the risk reduction associated with postoperative outpatient VTE prophylaxis, the clinical factors associated with VTE events, and surgeon prescribing patterns regarding outpatient VTE prophylaxis. Methods: A commercially available database of 53 million unique patients, PearlDiver, was used to identify patients with breast cancer who underwent microsurgical breast reconstruction. Patients were grouped into those receiving any form of outpatient VTE prophylaxis at discharge and those who did not. Probability of VTE within 90 days was calculated for each group followed by absolute risk reduction and number needed to treat. A logistic regression, assuming binomial distribution, was performed to determine clinical factors associated with VTE events after surgery. Results: A total of 22,606 patients underwent microsurgical breast reconstruction from 2010 to 2020. Of these patients, 356 (1.6%) were discharged with VTE prophylaxis and 22,250 (98.4%) were discharged without. No patients developed a VTE in the prophylaxis group, and 403 (1.8%) developed a VTE in the group without prophylaxis. The number needed to prevent one VTE was 55.25 patients. Most VTE events occurred after postoperative day 10 (71.3%). Conclusions: Outpatient chemoprophylaxis following breast reconstruction is underused despite the majority of VTE events occurring after the acute postoperative period. Breast microsurgeons should consider routine outpatient chemoprophylaxis as part of their postoperative care pathway to optimize VTE prevention. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.