Pain relief after total hip replacement: oral CR oxycodone plus IV paracetamol versus epidural levobupivacaine and sufentanil. A randomized controlled trial.

BACKGROUND: We tested the hypothesis that pain relief after total hip replacement (THR) can be obtained with a multimodal approach using oral controlled release (CR) oxycodone plus IV paracetamol. METHODS: Two hundred and sixty patients undergoing THR were randomized into two groups. A group of 130 patients (EPI) under epidural anesthesia followed by continuous infusion of levobupivacaine 0.125% and sufentanil 0.7mcg/mL at 7 mL/h was compared with a group (OXY) of 130 patients under spinal anesthesia and oral CR oxycodone 10 mg/q12h plus IV paracetamol 1g/q6h. Pain intensity at rest and dynamic by visual analogue scores (VAS), rescue dose consumption and side effects of three postoperative days (POD) were collected and analyzed with Mann-Withney test (P<0.05 was considered significant). RESULTS: VAS values at rest were similar in both groups at POD#1, significantly lower in the OXY group either at POD#2 (P=0.018) and POD#3 (P=0.001). Dynamic VAS values were significantly lower in the EPI group at POD#1 (P=0.001), similar for both groups at POD#2 and significantly lower in the OXY group at POD#3 (P=0.026) than the comparing group. Rescue dose consumption was significantly lower in the EPI group during the POD#1 (P=0.009), similar for both groups at POD#2 and higher in the EPI at POD#3 (P=0.008). The incidence of vomiting was similar for the two groups. Nausea was more frequent in the OXY group at POD#3 and more hypotension events occurred in the OXY group at POD#2. CONCLUSION: Oral CR oxycodone plus IV paracetamol was as effective as epidural levobupivacaine and sufentanil for postoperative pain relief after THR.