Background The VTEPS Network is a consortium of five tertiary referral centers established to examine venous thromboembolism in plastic surgery patients. We report our mid-term analyses of the study’s control group to 1) evaluate the incidence of VTE in patients who receive no chemoprophylaxis and 2) validate the Caprini Risk Assessment Model (RAM) in plastic surgery patients. Study Design Medical record review was performed at VTEPS centers for all eligible plastic surgery patients between March 2006 and June 2009. Inclusion criteria were Caprini score ≥ 3, surgery under general anesthesia, and post-operative hospital admission. Patients who received chemoprophylaxis were excluded. Dependent variables included symptomatic DVT or PE within the first 60 post-operative days and time to DVT or PE. Results We identified 1126 historic control patients. The overall VTE incidence was 1.69%. Approximately one in nine (11.3%) patients with Caprini score >8 had a VTE event. Patients with Caprini score >8 were significantly more likely to develop VTE when compared to patients with Caprini score of 3–4 (OR 20.9, p<0.001), 5–6 (OR 9.9, p<0.001), or 7–8 (OR 4.6, p=0.015). Among patients with Caprini score 7–8 or Caprini score >8, VTE risk was not limited to the immediate post-operative period. Conclusions The Caprini RAM effectively risk-stratifies plastic and reconstructive surgery patients for VTE risk. Among patients with Caprini score >8, 11.3% have a post-operative VTE when chemoprophylaxis is not provided. In higher risk patients, there was no evidence that VTE risk is limited to the immediate post-operative period.

Background Venous thromboembolism (VTE) is a major patient safety issue. The PSF-sponsored Venous Thromboembolism Prevention Study (VTEPS) examined whether post-operative enoxaparin prevents symptomatic VTE in plastic surgery patients. Methods VTEPS eligibility criteria included age ≥18, general anesthesia, and post-operative hospital admission. In 2009, four sites uniformly adopted a clinical protocol. Patients with Caprini score ≥3 received post-operative enoxaparin prophylaxis starting 6–8 hours after surgery and continuing for the duration of their inpatient stay. VTEPS historic control patients had an operation between 2006 and 2008 but received no chemoprophylaxis for 60 days after surgery. The primary study outcome was symptomatic 60-day VTE. Stratified analyses were performed. Multivariable logistic regression controlled for baseline risk and other identified confounders. Results 3334 patients (1876 controls and 1458 enoxaparin patients) were included. Notable risk reduction was present in patients with Caprini >8 (8.54% vs. 4.07%, p=0.182) and Caprini 7–8 (2.55% vs. 1.15%, p=0.230) who received post-operative enoxaparin. Logistic regression was limited to highest risk patients (Caprini ≥7) and demonstrated that length of stay (LOS) ≥4 days (adjusted odds ratio (OR) 4.63, p=0.007) and Caprini score >8 (OR 2.71, p=0.027) were independent predictors of VTE. When controlling for LOS and Caprini score, receipt of post-operative enoxaparin was protective against VTE (OR 0.39, p=0.042). Conclusions In high-risk plastic surgery patients, post-operative enoxaparin prophylaxis is protective against 60-day VTE when controlling for baseline risk and LOS. Hospitalization ≥4 days is an independent risk factor for VTE. Clinical Question Risk Level of Evidence III (retrospective cohort study)