Research reportEarly care of acute hyperglycemia benefits the outcome of traumatic brain injury in rats

- Only severe TBI could induce acute hyperglycemia by itself.
- Severity and site of TBI could influence acute hyperglycemia and outcomes.
- Early care of acute hyperglycemia could benefit outcome of TBI.

ObjectivePrevious animal studies showed contradictory clinical observations on whether acute hyperglycemia contributes to poor outcome in traumatic brain injury (TBI). Herein, we tried to clarify this issue.MethodsStriking with depths of 3.0-4.25 mm at right occipitoparietal brain region and with depth of 3.75 mm at right/left occipitoparietal or right/left frontoparietal brain region were performed, respectively. Blood glucose and insulin levels were traced every four hours from 1 to 72 h after striking. HOMA2-%S and HOMA2-%β were calculated. Modified neurological severity scores (mNSS) were used to evaluate neurological deficit within 72 h.ResultsStriking with depths of 3.5-4.25 mm induced increase in blood glucose lasting up to 24 h after striking. The levels of blood glucose after striking with depths of 3.75-4.25 mm were significantly different from that of striking with the depth of 3.0 mm. Striking with depth of 3.75 mm at right/left occipitoparietal region induced higher blood glucose in 24 h than that at right/left frontoparietal region. Insulin concentration increased slowly during 72 h after striking. Striking also induced decrease in insulin sensitivity and secretion lasting 72 h. Evaluation of mNSS revealed that severe striking (beyond 3.75 mm) worsened nerve function than slight striking (<3.0 mm). Intervention of acute hyperglycemia could decrease the mNSS from 2 to 7 days after TBI.ConclusionOur results suggested that only severe TBI could induce acute hyperglycemia by itself, and early care of acute hyperglycemia could benefit the outcome of TBI patients.