Vitamin E attenuates acute lung injury in sheep with burn and smoke inhalation injury

Introduction: A decrease in α-tocopherol (vitamin E) plasma levels in burn patients is typically associated with increased mortality. We hypothesized that vitamin E supplementation (α-tocopherol) would attenuate acute lung injury induced by burn and smoke inhalation injury. Materials and methods: Under deep anesthesia, sheep (33 ± 5 kg) were subjected to a flame burn (40% total body surface area, third degree) and inhalation injury (48 breaths of cotton smoke, < 40°C). Half of the injured group received α-tocopherol (1000 IU vitamin E) orally, 24 h prior to injury. The sham group was neither injured nor given vitamin E. All three groups (n = 5 per group) were resuscitated with Ringer's lactate solution (4 ml/kg/%burn/24 h), and placed on a ventilator (PEEP = 5 cmH₂O; tidal volume = 15 ml/ kg) for 48 h. Results: Plasma α-tocopherol per lipids doubled in the vitamin E treated sheep. Vitamin E treatment prior to injury largely prevented the increase in pulmonary permeability index and moderated the increase in lung lymph flow (52.6 ± 6.2 ml/min, compared with 27.3 ± 6.0 ml/min, respectively), increased the PaO₂/FiO₂ ratio, ameliorated both peak and pause airway pressure increases, and decreased plasma conjugated dienes and nitrotyrosine. Conclusions: Pretreatment with vitamin E ameliorated the acute lung injury caused by burn and smoke inhalation exposure.