Persistent pain following knee arthroplasty.

BACKGROUND AND OBJECTIVE: The prevalence of persistent pain after orthopaedic surgery has been the subject of only few studies and the risk factors for persistent pain have been evaluated even more rarely. The purpose of the present study was to evaluate the degree and the risk factors of persistent pain after knee arthroplasty. METHODS: The prevalence of persistent postoperative pain after knee replacement was evaluated with a questionnaire in a large, register-based cross-sectional prevalence study. The main hypothesis was that the type of operation (primary, bilateral, revision) would influence the prevalence of persistent postoperative pain. Logistic regression analysis was performed to test the hypothesis and to find other possible risk factors for the development of persistent pain. RESULTS: The total number of patients was 855. The operation was a primary arthroplasty in 648 patients (75.7%), a bilateral arthroplasty in 137 patients (21.1%) and a revision arthroplasty in 70 patients (8.2%). The response rate was 65.7%. The type of operation was not associated with the prevalence of persistent pain, but the degree of early postoperative pain was the strongest risk factor. If the degree of pain during the first postoperative week was from moderate to intolerable, the risk for the development of persistent pain was three to 10 times higher compared with patients complaining of mild pain during the same period. Other risk factors were the long duration of preoperative pain and female sex. CONCLUSION: Intensity of early postoperative pain and delayed surgery increase the risk of the persistent pain after knee arthroplasty.

The effect of parecoxib on kidney function at laparoscopic hysterectomy.

Conventional nonsteroidal anti-inflammatory drugs (NSAIDs) have a well-documented nephrotoxic action. Still, there are only few studies that have investigated the nephrotoxicity of cyclo-oxycenase-2-inhibitors during the perioperative period. Thirty patients scheduled for elective laparoscopic hysterectomy were enrolled in this prospective, randomized double-blind study. Patients were randomized into two groups: a saline-treated control group (placebo) and 80 mg parecoxib-treated group (parecoxib). The samples for the analyses of serum and urine were collected at the induction of anesthesia, two hours thereafter, two hours from the end of anesthesia, and on the first postoperative day (POD). S-crea, S-urea, S-cystatin C, S-Na, S-K, U-1mikroglobulin/U-crea, U-GST/U-crea, and U-GST/U-crea were analyzed from the samples. Urine output was measured every hour for the first five hours, and total amount of urine was measured until the first postoperative day. There were no clinical and few statistical significant differences between the two groups in the renal measurements during the study period. The urinary output was also similar in the two groups. A single dose of 80 mg of parecoxib was well tolerated by the kidneys in the short-term perioperative use in patients undergoing laparoscopic hysterectomy with ASA physiological status I-II and age under 60 years.