[Postoperative analgesic and anti-inflammatory effects of rofecoxib after total knee replacement].

OBJECTIVE

To evaluate the analgesic efficacy and systemic anti-inflammation of preoperative cyclooxygenase-2 nonsteroidal antiinflammatory drug, rofecoxib, after total knee replacement (TKR).

METHODS

Thirty patients underwent elective knee replacement were randomly given oral rofecoxib 25 mg (group RE, n = 15) or placebo (group E, n = 15) 1 hour prior to surgery. All patients received epidural combined isoflurane anesthesia during surgery and patient-controlled epidural analgesia after surgery for 72 hrs (0.1 mg/ml morphine + 1.2 mg/ml bupivacaine + 0.02 mg/ml droperidol). Modified verbal rate scale was used to evaluate postoperative pain intensity. The outcomes included pain scores during rest and movement of knee joints and analgesia satisfaction. Daily morphine consumption was recorded. Circulation leucocyte and serum cytokine concentrations (including interleukin 6, interleukin 8, interleukin 10, Tumor necrosis factor-alpha) were determined before surgery, at the end of surgery, 2 h, 6 h, 12 h, 24 h and 48 h after surgery in two groups using RIA. The amount of intraoperative blood loss and postoperative drainage from the knees were measured.

RESULTS

The pain scores were significantly less in the group RE than in group E during rest and knee joints movement on the first and second postoperative day, with an improvement in total analgesia satisfaction (P < 0.05). The mean dose of morphine for first 24 h was (8.1 +/- 1.5) mg in the E group and (6.8 +/- 0.7) mg in the RE group (t = -2.71, P < 0.01). Leucocyte and neutrophil counts were much higher in group E than in group RE at 12 h, 24 h post-operatively (P < 0.05). Serum TNF-alpha concentration was significantly lower in group RE than group E at the end of surgery, 6 h, 12 h postoperatively, as well as IL6 at 48 h, IL8 at 24h after surgery (P < 0.05). There were no significant differences in respect to the amount of intraoperative and postoperative blood loss between two groups (P > 0.05).

CONCLUSION

Preoperative cyclooxygenase-2-specific nonsteroidal anti-inflammatory drug rofecoxib increases analgesia satisfaction, reduces opioid requirement and demonstrates a systemic anti-inflammatory effect after TKR.