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Comparison of the effects of magnesium and ketamine on postoperative pain and morphine consumption. A double-blind
Müge Arıkan1, Bilge Aslan2, Osman Arıkan1
1School of Medicine, Karabuk University, Turkey.
Purpose:
To compare the effects of magnesium sulfate and ketamine on postoperative pain and total morphine consumption in a placebo-controlled design.
Methods:
One hundred and twenty women scheduled for total abdominal hysterectomy were included in this prospective, randomized, double-blind study. Postoperatively, when the Numeric Pain Rating Scale (NPRS) was four or more, IV-PCA morphine was applied to all patients. The patients were randomized into three groups: Group K ketamine, Group M magnesium, and Group C saline received as infusion. Total morphine consumption for 48h, pain scores, adverse effects, and patients' satisfaction were evaluated.
Results:
Total morphine consumption was significantly lower in Group K (32.6±9.2 mg) than in Group M (58.9±6.5 mg) and in Group C (65.7±8.2 mg). The satisfaction level of patients in Group K was higher than the other two groups (p<0.05). Pruritus and nausea were observed more frequently in Group C. CONCLUSİON: The addition of ketamine to IV-PCA morphine reduces the total consumption of morphine without psychotic effects; however, magnesium did not influence morphine consumption.
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