The Effects of EPA, GLA, and Antioxidant-Enriched Enteral Nutrition on Oxidative Stress and Oxygenation in Patients With ARDS: A Prospective, Randomized, Controlled Trial

Objective:The aim of this study was to determine the effects of eicosapentaenoic acid (EPA), gamma linolenic acid (GLA), and antioxidant-enriched enteral nutrition on oxidative stress and oxygenation in patients with acute respiratory distress syndrome (ARDS).Methods: This prospective randomized controlled clinical trial included 41 patients suspected of having of ARDS.Group C received high-carbohydrate enteral nutrition, and group E received enteral nutrition enriched with EPA, GLA, and antioxidants.The control group included 10 healthy volunteers used to compare basal enzyme levels.Oxidative stress was evaluated via measurement of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), xanthine oxidase (XAO), and malonaldehyde (MDA) levels in blood samples.Patients were followed-up for 7 d, and on d 1, 4, and 7 blood samples were collected.Ventilatory settings, including the PaO:FiO ratio, positive-end expiratory pressure (PEEP), peak inspiratory pressure (PIP), and minute ventilation volume (MV), were recorded daily. Results:In total, 31 of the 41 patients completed the study.Findings for d 1 showed that the ARDS patients had antioxidant enzyme deficiency, as compared to the healthy controls.XAO and GPx levels in group E increased daily and the difference between successive days were significant (p<0.05).CAT and SOD levels in groups C and E did not differ between days.In group E the MDA level decreased significantly over time (p<0.05).There weren't any significant differences in PEEP, PIP, MV, or the PaO:FiO ratio between baseline and d 7 of the study.Oxygenation in group E did improvement during the study. Conclusion:EPA, GLA, and antioxidant-enriched enteral nutrition in patients with ARDS increased antioxidant enzyme levels and reduced lipid peroxidation, which decreased oxidative stress, but did not improve gas exchange or oxygenation.