This study investigated the preemptive analgesic effects of Morphine and Ketorolac on postoperative pain, cortisol, O₂ saturation and heart rate for the first 24 hr after abdominal surgery.

Data collection was performed from April 1 to September 30, 2006. Forty patients undergoing a gastrectomy under general anesthesia were randomly allocated to the experimental or control group. The experimental group (20 patients) was administered Morphine and Ketorolac approximately 1 hr prior to skin incision, but the control group (20 patients) was administered Morphine and Ketorolac at peritoneum closure through a patient-controlled analgesia (PCA) pump. Postoperative pain, blood pressure, heart rate, cortisol, O₂ saturation, frequency of the PCA button pressed and doses of additional analgesics were observed through post operative 24 hr. Collected data was analyzed using t-test, χ² test, repeated measures ANOVA, and Bonferroni methods.

Postoperative pain, cortisol, the frequency of PCA button pressed, and dose of additional analgesics of the experimental group were significantly lower than the control group. There were no statistical differences in blood pressure, heart rate and O₂ saturation between the experimental group and control group.

We concluded that administration of morphine and ketorolac at 1 hr prior to skin incision resulted in decreasing postoperative pain, but it didn't affect blood pressure, heart rate or O₂ saturation for 24 hr after abdominal surgery.

This study was performed to evaluate the pre-emptive analgesic effects of a small dose of intravenous ketamine on postoperative pain in patients undergoing a hysterectomy.

Sixty patients undergoing a hystrectomy under general anesthesia were randomly allocated to 2 groups. The experimental group(30 patients) received 0.3mg/kg of ketamine after induction of anesthesia, approximately 5 min prior to surgery, but the control group(30 patients)did not receive ketamine. Data was collected in a double-blind manner from April 1st, to October 30th, 2004. Postoperatively, the patients used a patient-controlled analgesia(PCA) pump. Blood pressure, pulse rate, pain, anxiety, count of times pressing the PCA button, administeration of additional analgesics and side effects of ketamine were measured at 1 hour, 3 hours, 6 hours and 24 hours after the operation.

There were no statistical differences in blood pressure, pulse rate, pain and anxiety between the experimental and control groups. There were statistical differences in blood pressure, pulse rate, pain and anxiety during the 24 hours postoperatively. In the experimental group, the number of times pressing the PCA button and administering additional analgesic drugs were significantly lower than those of the control group.

A 0.3 mg/kg dose of ketamine given at approximately 5 min before surgery resulted in decreasing the number of times pressing the PCA and the administration of additional analgesics.