Patient controlled intravenous opioid analgesia versus continuous epidural analgesia for pain after intra-abdominal surgery

Abstract

There are two common techniques for postoperative pain control after intra-abdominal surgery: patient-controlled analgesia (PCA) with intravenous opioids and continuous epidural analgesia (CEA). It is uncertain which method has better pain control and fewer adverse effects. The objective of this review was to compare PCA opioid therapy with CEA for pain control after intra-abdominal surgery in terms of analgesic efficacy, side effects, patient satisfaction and surgical outcome by meta-analysis of the relevant trials. We searched CENTRAL (The Cochrane Library Issue 4, 2002), MEDLINE (January 1966 to October 2002), EMBASE (January 1988 to October 2002), and reference lists of articles. We also contacted researchers in the field. Randomized controlled trials of adult patients after intra-abdominal surgery comparing the effect of two pain control regimens in terms of analgesic efficacy and side effects. In the patient-controlled analgesia (PCA) group the patient should be able to operate the device himself. In the continuous epidural analgesia group there was no PCA device. Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information. Adverse effects information was collected from the trials. Nine studies involving 711 participants were included. The PCA group had a higher pain visual analogue scale than the CEA group during 6, 24 and 72 hour periods. The weighted mean difference and 95% confidence interval of resting pain was 1.74 (95% CI 1.30 to 2.19), 0.99 (95% CI 0.65 to 1.33), and 0.63 (95% CI 0.24 to 1.01), respectively. The length of hospital stay and other adverse effects were not statistically different except that the incidence of pruritus was lower in the PCA group, odds ratio of 0.27 (95% CI 0.11 to 0.64). CEA is superior to opioid PCA in relieving postoperative pain for up to 72 hours in patients undergoing intra-abdominal surgery, but it is associated with a higher incidence of pruritus. There is insufficient evidence to draw comparisons about the other advantages and disadvantages of these two methods of pain relief.