Management of Upper Extremity Vascular Injury: Outcome Related to the Mangled Extremity Severity Score

Background: The Mangled Extremity Severity Score (MESS) is an objective criterion for amputation prediction after lower extremity injury as well as for amputation prediction after upper extremity injury. A MESS of >or=7 has been utilized as a cutoff point for amputation prediction. In this study, we examined the result of upper extremity vascular injurty (UEVI) management in terms of the amputation rate as related to the MESS.

Methods: During January 2002 to July 2007, we reviewed patients with UEVIs at our institution. Data collections included demographic data, mechanism of injuries, injury severity score (ISS), ischemic time, MESS, pathology of UEVI, operative management, and amputation rate. Decisions to amputate the injured limbs at our institution were made individually by clinically assessing limb viability (i.e., color and capillary refill of skin; color, consistency, and contractility of muscles) regardless of the MESS. The outcome was analyzed in terms of the amputation rate related to the MESS.

Results: There were 52 patients with UEVIs in this study: 25 (48%) suffered blunt injuries and 27 (52%) suffered penetrating injuries. The age ranged from 15 to 59 years (mean 28.7 years). The mean ischemia time was 10.07 h. The mean ISS was 17.52. There were 12 patients (23%) with subclavian artery injuries, 3 patients (5.76%) with axillary artery injuries, 18 patients (34.61%) with brachial artery injuries, and 19 patients (36.54%) with radial artery and/or ulnar artery injuries. Primary repairs were performed in 45 patients (86.54%), with ligations in 3 patients (5.77%). An endovascular stent-graft was used in one patient (1.92%). Primary amputations were performed in three patients (5.77%). Secondary amputations (amputation after primary operation) were done in 4 of 49 patients (secondary amputation rate 8.16%). All amputation patients suffered blunt injuries and had a MESS of >or=7 (range 7-11). The overall amputation rate in this study was 13.46% (7/52 patients). Multivariate analysis revealed that the only factor significantly associated with amputation was the MESS. There were no amputations in 33 patients who had a MESS of <7. We could avoid amputation in 12 of 19 patients who had a MESS>or=7. There were no mortalities among 52 UEVI patients.

Conclusions: MESS, an outcome score used to grade the severity of extremity injuries, correlates well with the risk of amputation. Nevertheless, a MESS of >or=7 does not always mandate amputation. On the other hand, the MESS is a better predictor for patients who do not require amputation when the score is <7. The decisions to amputate in patients should be made individually based on clinical signs and an intraoperative finding of irreversible limb ischemia.