Ropivacaine exhibits less cardiotoxicity and causes less motor block than bupivacaine when used in equianalgesic doses. This makes ropivacaine potentially well suited for epidural infusion for postoperative analgesia. The aim of this study was to determine which of three concentrations of epidurally administered ropivacaine infused for postoperative analgesia would attenuate intravenous opioid analgesia requirements while also minimizing motor block. Forty ASA I-III patients, having major lower abdominal surgery, completed the study. They were randomly assigned to one of four treatment groups: Group S, control, epidural saline (n = 10); Group 1, epidural 0.1% ropivacaine (n = 10); Group 2, epidural 0.2% ropivacaine (n = 10); and Group 3, epidural 0.3% ropivacaine (n = 10). The study was double-blind. Initial epidural analgesia was established with 0.5% ropivacaine, and then general anesthesia induced for surgery. Once in the recovery room, epidural infusions were commenced at 10 mL/h and maintained at that rate for 21 h. Intravenous patient controlled analgesia (PCA) morphine was used as required by the patients for supplemental analgesia. Total PCA morphine use was more over the 21-h period in Group S than all the ropivacaine groups, being significantly so for Group 2 (median values: Group S, 43.3 mg; Group 1, 18.7 mg; Group 2, 7.5 mg; Group 3, 19 mg; for Group 2, P = 0.03). Visual analog scale (VAS) scores on coughing were significantly lower (i.e., less pain) than control for all ropivacaine groups after 4 h of infusion and also for Groups 2 and 3 after 8 h of infusion. (Median VAS (mm) on coughing at 8 h: Group S = 70, Group 1 = 56, Group 2 = 32, Group 3 = 0; for Groups 2 and 3, P < 0.05 compared to Group S). There was a dose-related increase in the amount of motor block, with Group 3 having significantly more motor block than all other groups at 4 and 8 h.(ABSTRACT TRUNCATED AT 250 WORDS)

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We studied 151 patients undergoing total hip or knee arthroplasty, or cruciate ligament reconstruction in a multicentre study in Australia and New Zealand. Patients were openly allocated randomly to one of five treatment groups or to a control group. General anaesthesia was induced after introduction of extradural block with 0.5% ropivacaine. After surgery, patients received an extradural infusion of 0.2% ropivacaine at 6, 8, 10, 12 or 14 ml h-1 or received no postoperative extradural infusion (control group). All patients had access to i.v. PCA morphine for supplementary analgesia. Morphine consumption was lower in all treatment groups compared with the control group, decreasing with increasing ropivacaine infusion rate. Median VAS scores were lower in all ropivacaine infusion groups compared with the control group for the first 10 h of the study; however by the end of the study, VAS scores were similar in all groups. The higher ropivacaine infusion rates caused a slower convergence of spread of the initial sensory block and a higher degree of motor block. The overall incidence of side effects was similar, with the exception of a higher incidence of urinary retention and hypotension in the groups receiving the higher rates of ropivacaine. The quality of treatment scores were similar for all treatment groups (Br. J. Anaesth. 1996; 76: 606-610).

Malignant hyperthermia (MH) has been reported as non-existent in children less than 1 yr old, although several unconfirmed reports have been published. A case report of MH in a 6-month-old child is presented, with confirmation of MH susceptibility by in vitro contracture testing of quadriceps muscle at 13 yr old. Genetic analysis revealed a novel RYR1 mutation that substitutes arginine 2452 for tryptophan in a region of the calcium channel mutated in several other MH pedigrees.

The purpose of this study was to compare the use of 0.5% ropivacaine with 0.5% bupivacaine for axillary brachial plexus anaesthesia. Sixty-six patients undergoing upper limb surgery were enrolled in a double-blind, randomized, multicentre trial. Five patients were subsequently excluded for various reasons. Of the remaining patients, 30 received 40 ml of 0.5%) ropivacaine and 31 received 40 ml of 0.5% bupivacaine. Brachial plexus block was performed by the axillary approach using a standardized technique with a peripheral nerve stimulator. Parameters investigated included the frequency, onset and duration of sensory and motor block, the quality of anaesthesia and the occurrence of any adverse events. The six principal nerves of the brachial plexus were studied individually. The frequency for achieving anaesthesia per nerve ranged from 70 to 90% in the ropivacaine group and 81 to 87% in the bupivacaine group. The median onset time for anaesthesia was 10 to 20 minutes with ropivacaine and 10 to 30 minutes with bupivacaine, and the median duration was 5.3 to 8.7h with ropivacaine and 6.9 to 20.3h with bupivacaine. Motor block was evaluated at the elbow, wrist and hand, and was completely achieved at a rate of 60 to 73% in the ropivacaine group and 55 to 71% in the bupivacaine group. The median duration of motor block was 6.5 to 7.5h with ropivacaine and 6.0 to 9.0h with bupivacaine. These parameters were not statistically different. The duration of partial motor block at the wrist (6.8 v 16.4h) and hand (6.7 v 12.3h) was significantly longer with bupivacaine. Ropivacaine 0.5% and bupivacaine 0.5%) appeared equally efficacious as long-acting local anaesthetics for axillary brachial plexus block.

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A case for coordinated investigation and reporting of hypersensitivity-type drug reactions in the UK

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