Effect of Combined Use of Naloxone and Tramacet on Postop Analgesia in Elderly Patients Having Joint Replacement Surgery

Group A: oral tramacet 2 tablets preoperatively, then 2 tablets every 6 hours for 5 days then 1-2 tablets of tramacet prn to a maximum of 8 tablets per day. A naloxone infusion will started preop at 0.25ug/kg/hr and will continue during patient's stay in hospital (an equivalent of 400ug over 24 hours in a 70 kg man). Infusion discontinued 1 hour before patient discharge. All the patients in groups A and B will be provided Morphine PCA for the duration of their hospital stay. Use of morphine PCA will be noted.Oral celebrex 200mg will be given to all the patient twice a day for five days as per our standard practice. All patients will receive peri-articular infiltration with local anesthetic solution intraoperatively by the surgeon as per our standard practice.

Group B: oral tramacet 2 tablets preop,then 2 tablets every 6 hours for five days(or until discharge. Patient VAS after discontinuation of morphine PCA may dictate addition of oral narcotic oxycodone after discharge). Group also receives saline infusion at 4-6mls/hour during hospital stay.All patients in groups A and B will have Morphine PCA during hospital stay. Use of morphine PCA will be noted. Oral celebrex 200mg will be given to all the patient twice a day for five days as per our standard practice. All patients will receive peri-articular infiltration with local anesthetic solution intraopby the surgeon as per our standard practice.

Group C will receive oral Acetaminophen tablets 1 gm preoperatively and subsequently 6 hourly plus an infusion of saline (placebo) at a rate of 4-6mls / hour for the duration of their stay. Oral celebrex 200mg will be given to all the patient twice a day for five days as per our standard practice. All patients will receive peri-articular infiltration with local anesthetic solution intraoperatively by the surgeon as per our standard practice. The Visual Analogue Scale, the Ramsay Sedation Score and the Mini Mental State Exam will be used to assess the patients for pain, sedation and confusion every 6 hours while in hospital.