Effects of dexmedetomidine and midazolam on postoperative cerebral oxygen metabolism in patients with severe brain injury

ObjectiveTo investigate the effects of dexmedetomidine and midazolam on postoperative cerebral oxygen metabolism in patients with severe brain injury.

MethodsA total of 30 postoperative patients with severe brain injury were randomly divided into dexmedetomidine group (n=15) and midazolam group (n=15).The heart rate (HR), mean arterial pressure (MAP), Glasgow coma score (GCS), Richmond restless sedation score (RASS), cerebral oxygen uptake rate and cerebral arteriovenous oxygen content difference before sedation and from the first to the fifth day of sedation were monitored, as well as the mechanical ventilation time, ICU hospital stay, total hospital stay, and 28-day Glasgow prognosis score.

ResultsThere were no differences in age, gender, type of brain injury, Acute Physiology Age and Chronic Health Evaluation II score, GCS score and postoperative RASS score between the two groups (P>0.05).Before sedation, there were no significant differences in all indexes between the two groups (P>0.05).Compared with the midazolam group, the HR decreased on the first to fifth day in the dexmedetomidine group, and the MAP decreased on the fourth and fifth day (P < 0.05 to P < 0.01).Compared with that before sedation, HR decreased from the third day to the fifth day after sedation and MAP decreased from the first day to the fifth day after sedation in the dexmedetomidine group (P < 0.05 to P < 0.01).Compared with the midazolam group, the oxygenation index, jugular bulb venous oxygen pressure and jugular bulb venous oxygen saturation were increased in the dexmedetomidine group on the first day and second day after sedation (P < 0.05 to P < 0.01), and there was no statistical difference between cerebral oxygen uptake rate and cerebral arteriovenous oxygen content (P>0.05).The duration of mechanical ventilation was shortened in the dexmedetomidine group compared with that in the midazolam group (P < 0.05).

ConclusionsCompared with midazolam, dexmedetomidine sedation can improve early cerebral oxygen metabolism, reduce HR and MAP, and shorten mechanical ventilation time in patients with severe craniocerebral injury.