Immediate and prolonged effects of pre- versus postoperative epidural analgesia with bupivacaine and morphine on pain at rest and during mobilisation after total knee arthroplasty.

Thirty-two patients scheduled for total knee arthroplasty were randomized to receive an identical epidural blockade initiated 30 min before surgical incision (N = 16), or at closure of the surgical wound (N = 16). Before induction of general anaesthesia the epidural catheter was tested with bupivacaine 7.5 mg.ml-1, 2 ml. General anaesthesia was induced with thiopentone, pancuronium or atracurium, and fentanyl 0.1-0.3 mg, and maintained with N2O/O2 and enflurane. The epidural regimen consisted of a bolus of 16 ml of bupivacaine 7.5 mg.ml-1 plus morphine 2 mg, and continuous infusion of bupivacaine 1.25 mg.ml-1 plus morphine 0.05 mg.ml-1, 4 ml.h-1 for the first 24 h, and bupivacaine 0.625 mg.ml-1 plus morphine 0.05 mg.ml-1, 4 ml.h-1, for the next 24 h after operation. Additional morphine 2.5-5 mg was administered i.v. or i.m. for the first 24 h postoperatively, and ketobemidone or morphine 5-10 mg orally or rectally from 24 h to 7 d postoperatively, on request. Paracetamol 1000 mg every 8 h was administered from 48 h to 7 days postoperatively. No significant differences were observed in request for additional opioids, or in pain scores at rest or during mobilisation of the operated limb, during or after cessation of the epidural regimen. These results do not suggest timing of analgesia with a conventional, continuous epidural regimen to be of major clinical importance in patients undergoing total knee arthroplasty.

Continuous blockade of the lumbar plexus after knee surgery--postoperative analgesia and bupivacaine plasma concentrations. A controlled clinical trial.

In a double blind, randomised, controlled investigation the analgesic effect of a continuous block of the lumbar plexus with bupivacaine compared with sodium chloride was examined in 20 patients with postoperative pain after knee-joint surgery. The infusion was given through a catheter inserted in the neurovascular fascial sheath of the femoral nerve, according to the three-in-one block technique. The patients treated with bupivacaine had significantly lower pain scores and a significantly lower demand for morphine. Side effects related to the catheters or the infusions of bupivacaine were not observed.

Perineuronal morphine: a comparison with epidural morphine.

In a double-blind, randomised controlled cross-over study the effects of perineuronal (perifemoral) injections of morphine were compared with epidural injections with the same amount of morphine in patients after knee surgery. Better pain scores were achieved during treatment with epidural morphine. We have not been able to confirm the hypothesis of neuro-axonal transport of morphine from the periphery to the spinal cord.

Patient-controlled analgesia: a controlled trial.

Thirty-six patients undergoing lower abdominal surgery were included in a prospective randomized controlled study to compare the effects of patient-controlled analgesia (PCA) and a standard intramuscular/intravenous treatment (conventional analgesia, CA) of postoperative pain. Morphine was used in both groups. There were no significant differences between the two analgesic regimens in respect of linear analogue pain scores, verbal pain-relief scores, amount of morphine used or side-effects. No treatment-induced alterations in vital values were experienced.