Patient controlled analgesia versus conventional analgesia for postoperative pain

Patients may control postoperative pain by self-administration of intravenous opioids using devices designed for this purpose [patient controlled analgesia or PCA]. This study set out to determine whether any of the two opioid administrations [i.e. PCA or conventional analgesia] would provide superior pain relief among patients undergoing laparoscopic cholecystectomy or not. In a clinical trial the PCA group received self-administered intermittent intravenous morphine via PCA and the conventional group received intravenous Pethidine every 6 hours per day. The patients were assessed on an hourly basis for the first 4 hours after surgery, every 2 hours for the next 8 hours and every 4 hours for next 12 hours. Two methods were used in order to evaluate the degree of pain relief in patients: [1] facial pain scale; pain assessment based on the patient's appearance and [2] numerical rating scale; based on patient ratings of their pain. Forty eight patients [79.1% female, 20.1% male] with a mean age of 45.7 +/- 10.7 years old were enrolled into the study. During the first 24 hours after laparoscopic cholecystectomy, pain intensity based on facial pain scale was lower in the PCA group. However, the difference was significant only in the second hour [mean pain score in PCA group: 2.9, mean pain score in conventional group: 3.7, P = .007]. Also, the mean pain scores based on numerical rating scale were significantly lower in PCA group except for the first hour. Although it was not significantly lower than conventional group [mean pain score in PCA group: 4.2, mean pain score in conventional group: 4.6, P = .45]. Intravenous PCA resulted in better postoperative pain reduction compared to intermittent bolus opioid delivery in laparoscopic cholecystectomy.