|89th Annual Meeting Abstracts
Validation of the Caprini Risk Assessment Model in Plastic and Reconstructive Surgery Patients
Christopher J. Pannucci, MD1, Steven Bailey, MD2, Christine Fisher, MD3, Julio Clavijo-Alvarez, MD PhD3, Jennifer Hamill, MPH4, Keith Hume, MA4, J. Peter Rubin, MD3, Edwin Wilkins, MD MS1, Ronald Hoxworth, MD2.
1University of Michigan, Ann Arbor, MI, USA, 2University of Texas-Southwestern, Dallas, TX, USA, 3University of Pittsburgh, Pittsburgh, PA, USA, 4American Society of Plastic Surgeons, Arlington Heights, IL, USA.
In contrast to other surgical subspecialties, the plastic surgery literature demonstrates a paucity of research regarding the efficacy of chemoprophylaxis in venous thromboembolism (VTE) prevention. As a result, the Plastic Surgery Educational Foundation recently established a consortium of three tertiary referral centers with demonstrated expertise in plastic and reconstructive surgery to perform a prospective cohort study with historic controls to examine the efficacy of low molecular weight heparin prophylaxis for VTE prevention in plastic surgery patients.
A mid-term analysis of the study’s control group was conducted to evaluate the incidence of VTE when chemoprophylaxis is not provided and to assess the predictive ability of the Caprini Risk Assessment Model (RAM) for VTE. Medical record review for patients undergoing plastic surgery between March 2006 and June 2008 was conducted. All patients with Caprini scores ≥ 3 having surgery under general anesthesia with post-operative hospital admission were included. Patients who received any form of chemoprophylaxis were excluded. Outcomes of interest included symptomatic DVT or PE (confirmed with imaging) within the first 60 post-operative days.
At present, 634 patients meeting inclusion criteria have been identified. Mean Caprini score was 5.3. VTE occurred in 16 patients (2.52%; 8 DVT, 4 PE, 4 DVT + PE) with 25% of VTE occurring between post-operative day 30 and 60. When compared to those with Caprini scores of 3-4, patients with Caprini scores of 5-6 (OR 1.41, p=.654) and Caprini scores of 7-8 (OR 3.34, p=.119) were more likely to develop VTE. Patients with Caprini scores > 8 were significantly more likely to develop VTE when compared to those with Caprini scores of 3-4 (OR 16.87, p<.001), Caprini scores of 5-6 (OR 11.95, p<.001), and Caprini scores of 7-8 (OR 5.05, p=.022). Based on preoperative risk factors, the Caprini RAM categorized 81% (13/16) patients who eventually developed VTE as “highest risk”. The Caprini RAM has good discrimination for VTE in this patient population (c-statistic=0.679).
Plastic and reconstructive surgery patients are at notable risk for perioperative VTE and the Caprini RAM is able to identify those patients at greatest risk. Patients with a Caprini score > 8 are at significantly increased risk to develop VTE. A separate “maximum” risk level may be warranted for these patients in future RAMs.