Grants We Funded

Abstract
Venous thromboembolism (VTE) is a leading cause of death among hospitalized patients, and is an important patient safety issue in plastic surgery. Previous work in plastic surgery has shown that enoxaparin prophylaxis can prevent many post-operative VTE events, and current American Society of Plastic Surgeons guidelines support enoxaparin prophylaxis for high-risk patients. However, the Plastic Surgery Foundation-funded Venous Thromboembolism Prevention Study showed that one in 25 highest risk patients still had a “breakthrough” VTE event despite receipt of guideline-compliant enoxaparin prophylaxis. Highest risk patients often have cancer or trauma reconstruction. These surgeries may have surgical injury that is equal in scope to patients with traumatic or thermal injury. Previous work in patients with traumatic or thermal injury has shown that enoxaparin metabolism, measured by anti-factor Xa (aFXa) level, is substantially increased: a higher degree of injury is associated with higher enoxaparin dose requirements to achieve prophylactic levels. “Breakthrough” VTE events may occur in plastic and reconstructive surgery patients due to inadequate enoxaparin dosing. We will examine enoxaparin pharmacokinetics and will test whether a clinical protocol for real-time enoxaparin dose adjustment can favorably alter the proportion of patients with in-range aFXa levels. Primary outcomes will include 1) peak and trough steady-state aFXa levels in response to standard and escalated doses of enoxaparin and 2) the proportion of patients with appropriate aFXa levels before and after initiation of a clinical protocol for enoxaparin dose adjustment. We expect that standard dosing will result in inadequate aFXa peak and trough levels, and that the clinical dose adjustment protocol will significantly improve the proportion of in-range aFXa levels. We will also develop a linear regression-based equation to calculate, based on patient-level factors, the required dose of enoxaparin to generate in-range aFXa levels. This research may show that the current “one size fits all” approach to enoxaparin prophylaxis is insufficient. In the trauma and orthopaedic populations, patients with low initial aFXa levels are significantly more likely to develop DVT. Thus, this research has important implications for appropriate enoxaparin dose magnitude and frequency, and may ultimately help to decrease the substantial morbidity and mortality associated with post-operative VTE.

Biography
Dr. Pannucci is an Assistant Professor of Plastic Surgery at the University of Utah. He received his Bachelor of Science degree from Indiana University and his Doctor of Medicine degree from Washington University in St. Louis. Dr. Pannucci completed an integrated residency in plastic and reconstructive surgery at the University of Michigan and a clinical fellowship in microvascular reconstruction at the University of Pennsylvania. He has a Masters degree in Health and Health Care Research through the Robert Wood Johnson Clinical Scholars program. Dr. Pannucci's research efforts focus on risk stratification and prevention of deep vein thrombosis and pulmonary embolus in surgical patients, with particular interest in risk model development and validation and prospective clinical trials.