Venous thromboembolism in trauma patients: Standardized risk factors

• Published in: Journal of vascular surgery 1998-08, Vol.28 (2), p.250-259
• Main Authors: Cafferata, H.Treat, Morrison, Snow, Duer, Cheryl, Depalma, Ralph G.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Child; Child, Preschool; Critical Care; Female; Heparin, Low-Molecular-Weight - administration & dosage; Humans; Infant; Length of Stay; Male; Middle Aged; Multiple Trauma - diagnostic imaging; Multiple Trauma - surgery; Postoperative Complications - diagnostic imaging; Postoperative Complications - etiology; Postoperative Complications - prevention & control; Practice Guidelines as Topic; Pulmonary Embolism - diagnostic imaging; Pulmonary Embolism - etiology; Pulmonary Embolism - prevention & control; Risk Factors; Thrombophlebitis - diagnostic imaging; Thrombophlebitis - etiology; Thrombophlebitis - prevention & control; Ultrasonography, Doppler
• ISSN: 0741-5214; 1097-6809
• DOI: 10.1016/S0741-5214(98)70161-2

Purpose: This study was done to evaluate the use of published standardized risk factors for venous thromboembolism (VTE) in patients admitted to a trauma intensive care unit (ICU) and to derive guidelines for the use of low molecular weight heparin (LMWH) and surveillance venous Doppler ultrasound scanning (VDUS). Methods: Patients were admitted to a regional trauma center ICU. Two periods were studied. Period 1 was a retrospective analysis of documented cases of VTE in the trauma registry from 1993 to 1995 (n = 39). The period was also a review of all patients admitted to a trauma ICU in 1994 without VTE who met the following criteria: age greater than 11 years, ICU stay of more than 36 hours, and survival of more than 72 hours (n = 227). Period 2 was a concurrent analysis of 1996 documented cases of VTE and similarly selected ICU admissions (VTE, n = 10; no VTE, n = 224). Risk factor scores (R1, admitting; R2, total) were calculated from the International Society for Cardiovascular Surgery/Society for Vascular Surgery reporting standards. The scores were cumulative by category and over time. The suitability of such standards was determined in period 1. The resulting therapeutic and surveillance guidelines were evaluated in period 2. Results: Period 1 risk factor scores, R1 and R2, were correlated with the occurrence of VTE from χ 2 test ( P < .05 and P < .01, respectively). Risk categories were grouped as low, moderate, and high. VTE was not observed in the low-risk group (0 to 2). Among all VTE (n = 49), 11 cases occurred in patients with moderate-risk scores and 38 in patients with high-risk scores. In 1994 and 1996, the selected groups were analyzed and the incidence rate of VTE was 4.7% in both years for the moderate-risk group and 2.5% and 4.8% for the high-risk group, respectively. Most VTE cases (78%) received some form of prophylaxis (PRx), and 26% of cases had multiple methods of prophylaxis (MPRx). This included 80% of the cases that received unfractionated heparin. In period 2, no pulmonary emboli (PE) occurred, in contrast to period 1, in which 16 of 39 cases of VTE (41%) were first seen with PE. In period 2, no patient receiving MPRx, including compression and LMWH, had VTE develop. Surveillance VDUS discovered 6〈$〉0% of 1996 cases in period 2. No PE were seen in period 2. Conclusion: Standard risk factors were easily applied to the trauma patient at the bedside. Patients at low risk needed no PRx. Patients at high risk did best with both co