Efficacy and Adverse Effects of Patient-Controlled Epidural or Intravenous Analgesia after Major Surgery.

Background: The purpose of this retrospective study was to determine whether epiduralfentanyl-bupivacaine patient-controlled analgesia (PCA) was more efficaciousand had fewer adverse effects than epidural or intravenous morphinePCA.Methods: We retrospectively retrieved data from 859 patients (mean age 64 7 years)who received continuous epidural medication, either morphine or fentanylbupivacainePCA, or intravenous morphine PCA for postoperative pain controlafter major elective surgery from 1999 to 2000. Pain was assessed postoperativelyusing a verbal analogue pain scale (VAS, 0-10) during rest, mobilization,and coughing. Adverse effects including nausea, vomiting, pruritus,urinary retention, sedation, motor block, and respiratory depression (< 8breaths per minute) were recorded. On the third postoperative day, the overallquality of pain control was evaluated using a pain relief scale (PRS, 1-4).Results: There were 201 patients who had epidural morphine PCA, 427 patients whohad fentanyl-bupivacaine PCA, and 231 patients who had intravenous morphinePCA. Most patients (> 86%) who received epidural or intravenousPCA, either morphine or fentanyl combined with bupivacaine, experiencedgood pain relief (VAS, 0-3) during rest, mobilization, and coughing.Nonetheless, patients who received epidural morphine or fentanyl-bupivacainehad greater satisfaction with overall pain relief (PRS = 4) than didthose who received intravenous morphine ( p < 0.05). Nausea and vomitingwere most common in the epidural morphine group ( p < 0.05). Pruritusoccurred least often in patients who received epidural fentanyl-bupivacaineanalgesia ( p < 0.05). There were no differences in other adverse events suchas urinary retention, sedation, and motor block among the three groups. Norespiratory depression was found in any patient.Conclusions: Patients receiving epidural fentanyl-bupivacaine PCA experienced betteroverall pain relief, while morphine PCA, either epidurally or intravenously,caused more side effects. It is considered safe to use continuous epiduralPCA with fentanyl-bupivacaine in patients receiving major elective surgery.