Diclofenac premedication but not intra-articular ropivacaine alleviates pain following day-case knee arthroscopy

Abstract

Purpose: To compare the postoperative analgesic effects of 50 mg diclofenac po before surgery and intra-articular ropivacaine injected after diagnostic day-case knee arthroscopy performed under spinal anesthesia. Methods: In a randomized, double-blind investigation, 200 ASA physical status 1-2 outpatients, age 18-60 yr, received either 50 mg diclofenac po or placebo one hour before operation (100 patients per group), and intra-articular injections of either 20 ml of ropivacaine 0.5% or 20 ml of saline 0.9% (50 patients in each premedication groups). Patients received 50 mg diclofenac po prn and, if needed, 0.1 mg · kg-1 oxycodone im for postoperative pain relief. Patients were discharged home with a supply of 50 mg diclofenac tablets and were given a sheet of paper with knee pain VAS scales and a questionnaire of analgesics taken. Patients rated their VAS scores eight hours after surgery and in the morning and at the end of the first and the second postoperative days, respectively. Results: The only statistically significant difference was found when the diclofenac groups were combined and compared with the combined placebo premedication groups. The VAS scores of knee pain at eight hours after the operation were 19 ± 22 in the two diclofenac premedication groups and 32 ± 28 in the two placebo groups (P=0.001). Conclusions: Diclofenac premeditation po reduced the VAS scores at eight hours postoperatively while intra-articular ropivacaine did not.