The effect of pre-anesthetic administration of dexmedetomidine on postoperative pain and morphine consumption in patient receiving abdominal hysterectomy

Background: Average pain intensity in patients who had abdominal hysterectomy are about moderate to severe and surgery can made anxiety. Objective: To evaluate effect of pre-anesthetic administration of dexmedetomidine on postoperative morphine consumption and pain intensity Method : 58 patients who scheduled for abdominal hysterectomy under general anesthesia were randomly allocated to receive intravenous dexmedetomidine 1 µg/kg or saline 10 min before induction of anesthesia. They are allowed to use a patient controlled analgesia (PCA) after surgery. Vital signs, sedation score were recorded at 0, 5 and 10 min between drip the drug or placebo and recorded morphine consumption, pain, discomfort score, time of recovery and any side effects at 1, 2, 6 and 24 hr after start of PCA. Results: There were no significant differences between groups about morphine consumption and time of recovery. Pain score at rest and move in dexmedetomidine group were significant lower than control group at 2 and 6 hr. During dexmedetomidine infusion, heart rate was lower and sedation score was higher than control group. Conclusion: A single dose of intravenous dexmedetomidine 1 µg/kg before induction of anesthesia could not reduce postoperative morphine consumption but pain scores were decreased. No effect on postoperative recovery time.