The Effect of the Initiating Time of Patient Controlled Analgesia on the Onset of Postoperative Analgesic Effect

Abstract

Background: Patient controlled analgesia (PCA) is now a widely accepted method of postoperative pain control. It usually begins at postanesthetic care unit, but it takes time to achieve satisfactory level. We have studied the differences in the onset of analgesic effects between starting PCA preoperatively and starting PCA postoperatively. Methods: Forty patients for subtotal gastrectomy were randomized to two groups. In group I, we started PCA at postanesthetic care unit, in group II, PCA was begun immediately after the induction of anesthesia. We visited each patient and measured 10 cm-visual analgue scale (VAS) score at 3, 6, 9, 12 and 15 hours after the end of operation. We also measured the time taken from the end of operation to extubation. Results: There were no differences in VAS score between two groups on 3 hour. But at 6, 9, and 12 hour, VAS score was significantly lower in group II (P