The effect of Polyethylene Glycol-Superoxide Dismutase on gastric mucosa and survival in shock with tissue injury.

Oxygen-derived free radicals may play an important role in the pathogenesis of organ injury and death following hemorrhagic shock. This study was designed to test the effects of Polyethylene Glycol-Superoxide Dismutase (PEG-SOD) on gastric mucosal injury and survival in an animal model of hemorrhagic shock and tissue trauma. Reproducible tissue trauma was produced by IM injection of turpentine (1.4 microliters/g). A standardized hemorrhagic shock model with an LD 90 was employed. This model consisted of the following sequence of events: phlebotomy to 60 per cent blood volume, 45-minute shock period, resuscitation using Lactated Ringers (LR) at two times shed volume over 60 minutes. Twenty rats were randomly assigned to receive LR (control) or PEG-SOD (5.36 mg/kg). Immediately following the death or at 72 hours, the stomach was removed. Computer image analysis was used to determine the lesion area as a per cent of total gastric mucosal surface area. Our results show no statistical difference in gastric mucosal lesion area between groups (1.83% vs 1.75%, respectively). Survival at 72 hours was significantly higher for PEG-SOD animals vs controls (70% vs 10%, P = 0.0001). This data suggests that IV administration of PEG-SOD during resuscitation is a potentially effective means of improving survival following severe hemorrhagic shock and tissue injury.