Impact of high-dose antioxidants on outcomes in acutely injured patients

Department of Surgery, Vanderbilt University Medical Center, Nashville, TN 37212, USA.
Journal of Parenteral and Enteral Nutrition (Impact Factor: 3.14). 07/2008; 32(4):384-8. DOI: 10.1177/0148607108319808
Source: PubMed

ABSTRACT The profound oxidative stress that occurs following injury results in significant depletion of many endogenous antioxidants (vitamin C, E, selenium). Increasing evidence suggests antioxidant supplementation reduces infectious complications and organ dysfunction following injury and hemorrhagic shock. The purpose of this study was to evaluate the impact of high-dose antioxidant administration on the mortality rate of acutely injured patients.
In October 2005, we implemented a 7-day high-dose antioxidant protocol for acutely injured patients admitted to our trauma center. A retrospective cohort study, evaluating all patients admitted to the trauma service between October 2005 and September 2006 following protocol implementation (AO+), was performed. The comparison cohort (AO-) was made up of those patients admitted in the year prior to protocol implementation.
A total of 4,294 patients met criteria (AO+, N = 2,272; AO-, N = 2022). Hospital (4 vs 3 days, P < .001) and ICU (3 vs 2 days, P = .001) median length of stays were significantly shorter in the AO+ group. Mortality was significantly lower in the AO+ group (6.1% vs 8.5%, P = .001), translating into a 28% relative risk reduction for mortality in patients exposed to high-dose antioxidants. After adjusting for age, gender, and probability of survival, AO exposure was associated with even lower mortality (OR 0.32, 95% CI 0.22-0.46). Patients with an expected survival <50% benefited most (OR 0.24, 95% CI 0.15-0.37).
A high-dose antioxidant protocol resulted in a 28% relative risk reduction in mortality and a significant reduction in both hospital and ICU length of stay. This protocol represents an inexpensive intervention to reduce mortality/morbidity in the trauma patient.

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