Tomoki Nishiyama1. 1. Department of Anesthesiology, The University of Tokyo, Tokyo, Japan.
Abstract
PURPOSE: We investigated the effective and safe dose of intravenous midazolam for sedation and amnesia during spinal anesthesia in patients premedicated with intramuscularmidazolam. METHODS:One hundred and eighty patients aged 20-50 years scheduled for spinal anesthesia receivedmidazolam 0.06 mg.kg(-1) and atropine 0.01 mg.kg(-1) intramuscularly 15 min before entering the operating room. Spinal anesthesia was performed with 0.5% hyperbaric tetracaine. Five minutes after starting surgery, midazolam 0 (control group), 0.01, 0.02, 0.03, 0.04, or 0.05 mg.kg(-1) was intravenously administered (30 patients each). Blood pressure, heart rate, respiratory rate, percutaneous oxygen saturation (S(p)(O)(2)), verbal response, eyelash reflex, and involuntary body movement were measured every 5 min for 30 min. Memory during surgery was also investigated. RESULTS: The number of the patients with loss of verbal response, with loss of eyelash reflex, and with no memory during surgery were significantly larger in the groups receiving midazolam >or=0.03 mg.kg(-1), >or=0.04 mg.kg(-1), and >or=0.02 mg.kg(-1), respectively. The decrease in blood pressure or increase in respiratory rate with decrease in S(p)(O)(2) was significantly larger in the groups receiving midazolam >or=0.03 mg.kg(-1) or 0.05 mg.kg(-1), respectively. CONCLUSION: For sedation and amnesia of the patients aged 20-50 years in spinal anesthesia with about 1 h duration receiving intramuscularmidazolam 0.06 mg.kg(-1) as a premedication, intravenous midazolam 0.02 mg.kg(-1) might be effective and safe.
RCT Entities:
PURPOSE: We investigated the effective and safe dose of intravenous midazolam for sedation and amnesia during spinal anesthesia in patients premedicated with intramuscular midazolam. METHODS: One hundred and eighty patients aged 20-50 years scheduled for spinal anesthesia received midazolam 0.06 mg.kg(-1) and atropine 0.01 mg.kg(-1) intramuscularly 15 min before entering the operating room. Spinal anesthesia was performed with 0.5% hyperbaric tetracaine. Five minutes after starting surgery, midazolam 0 (control group), 0.01, 0.02, 0.03, 0.04, or 0.05 mg.kg(-1) was intravenously administered (30 patients each). Blood pressure, heart rate, respiratory rate, percutaneous oxygen saturation (S(p)(O)(2)), verbal response, eyelash reflex, and involuntary body movement were measured every 5 min for 30 min. Memory during surgery was also investigated. RESULTS: The number of the patients with loss of verbal response, with loss of eyelash reflex, and with no memory during surgery were significantly larger in the groups receiving midazolam >or=0.03 mg.kg(-1), >or=0.04 mg.kg(-1), and >or=0.02 mg.kg(-1), respectively. The decrease in blood pressure or increase in respiratory rate with decrease in S(p)(O)(2) was significantly larger in the groups receiving midazolam >or=0.03 mg.kg(-1) or 0.05 mg.kg(-1), respectively. CONCLUSION: For sedation and amnesia of the patients aged 20-50 years in spinal anesthesia with about 1 h duration receiving intramuscular midazolam 0.06 mg.kg(-1) as a premedication, intravenous midazolam 0.02 mg.kg(-1) might be effective and safe.