Intrathecal midazolam acts synergically with other anesthetics to relieve surgical pain, and the drug combination may decrease complications attributable to each component drug. This prospective study was to determine the spinal effects of low-dose of bupivacaine (5 mg) combined with intrathecal midazolam (2 mg) in diabetes mellitus (DM) patients undergoing foot debridement. Sixty diabetic patients were admitted for foot debridement under spinal anesthesia were equally divided into two groups. Group 1 (M) received 7.5 mg of hyperbaric bupivacaine; group 2 (M+M) received 5 mg of hyperbaric bupivacaine combined with 2 mg of midazolam intrathecally. The intensity of motor block was assessed with modified Bromage scale 20 minutes after injection, and at 0, 30, 60, 90 and 120 min after arriving at the post anesthesia care unit (PACU). Pain score was assessed with a 10 cm visual analog scale (VAS, 0 = no pain and 10 = intolerable pain) at 0, 1, 2, 6 h and 24 h postoperatively. Anesthesia was smooth in all patients except one in group M, whose analgesia was inadequate and general anesthesia was given to complete the surgery. The number of patients who sustained moderate to severe pain (VAS > 5) was significantly less in the M+M group than in M group as accessed 6 and 24 h postoperatively. The requirement of additional analgesic as reinforcement was significantly less in the M+M group than in the M group within the space of 24 h postoperatively. Recovery of motor function was significantly faster in the M+M group. The combination of intrathecal midazolam and bupivacaine was a safe and effective anesthetic technique, and it also provided early recovery of motor function and reduced the requirement of analgesics postoperatively.

Wu, Shiau, Hong, Hung, Lu, Tseng, , , (2005). Intrathecal midazolam combined with low-dose bupivacaine improves postoperative recovery in diabetic mellitus patients undergoing foot debridement. Acta anaesthesiologica Taiwanica : official journal of the Taiwan Society of Anesthesiologists, 2005 Sep;43(3):129-34. https://www.ncbi.nlm.nih.gov/pubmed/16235460