Risk of Bleeding Versus Venous Thromboembolism After Surgery for Breast Cancer: A National Surgical Quality Improvement Program Analysis.

Introduction: Patients who undergo surgery for breast cancer are at risk for venous thromboembolism (VTE) and bleeding, which can lead to significant consequences on outcomes. This study examined factors related to VTE and bleeding risk in breast cancer surgery, with and without reconstruction. We also investigated the relationship between operative time and resident involvement on bleeding and VTE risk.

Methods: Using the ACS-NSQIP database, patients who underwent mastectomy, implant, pedicled, or free flap reconstruction from 2005 to 2021 were identified. Resident involvement was available from 2007 to 2010. We fitted two logistic regressions to model the log odds of bleeding occurrence and VTE as linear functions of procedure type, controlling for age, body mass index, and comorbidities.

Results: Implant reconstruction had significantly reduced 30-d incidence of bleeding, compared to those who underwent transverse rectus abdominus muscle flap (P < 0.001). Free flap was associated with a significant increase in bleeding but not VTE risk (P < 0.001; P = 0.132). Increase in operative time significantly increased the risk of bleeding and VTE (P < 0.001). For surgeries with resident involvement coded, there was no significantly increased risk of bleeding or VTE (P = 0.600; P = 0.766).

Conclusions: Implant reconstruction remains the procedure with the lowest risk of both bleeding and VTE. Free flap reconstruction did not show a significantly increased risk of VTE, potentially expanding reconstruction options for patients previously excluded from autologous reconstruction. Surgeons should be mindful of operative time, with re-evaluation of risk factors with each additional hour of surgery, irrespective of reconstruction type. Resident involvement in surgeries should continue to be encouraged by faculty.