Changes in First Postoperative Night Bispectral Index After Daytime Sedation Induced by Dexmedetomidine or Midazolam Under Regional Anesthesia: A Randomized Controlled Trial

1.111 elderly male patients undergoing TURP under spinal anesthesia were randomized to no sedation, sedation with midazolam, or sedation with dexmedetomidine. Intraoperative sedation and postoperative sleep were measured using BIS monitor. Sleep efficiency following surgery was found to be lowest in the dexmedetomidine group and sleep duration was approximately 240 minutes longer in the midazolam group compared to those who had been sedated with dexmedetomidine.

http://www.ncbi.nlm.nih.gov/pubmed/26928796