Neurological outcome after experimental lung injury.

Abstract

We examined the influences of acute lung injury and hypoxia on neurological outcome. Functional performance was assessed using a neurocognitive test and a neurologic deficit score (NDS) five days before. On experimental day, mechanically ventilated pigs were randomized to hypoxia only (HO group, n=5) or to acute lung injury (ALI group, n=5). Hemodynamics, respiratory mechanics, systemic cytokines and further physiologic variables were obtained at baseline, at the time of ALI, 2, 4 and 8h thereafter. Subsequently, injured lungs were recruited and animals weaned from the ventilator. Neurocognitive testing was re-examined for five days. Then, brains were harvested for neurohistopathology. After the experiment, neurocognitive performance was significantly worsened and the NDS increased in the ALI group. Histopathology revealed no significant differences. Oxygenation was comparable between groups although significantly higher inspiratory pressures occured after ALI. Cytokines showed a trend towards higher levels after ALI. Neurocognitive compromise after ALI seems due to a more pronounced inflammatory response and complex mechanical ventilation.