British journal of anaesthesia
-
Randomized Controlled Trial Clinical Trial
Differential effects of systemically administered ketamine and lidocaine on dynamic and static hyperalgesia induced by intradermal capsaicin in humans.
We have examined the effect of systemic administration of ketamine and lidocaine on brush-evoked (dynamic) pain and punctate-evoked (static) hyperalgesia induced by capsaicin. In a randomized, double-blind, placebo-controlled, crossover study, we studied 12 volunteers in three experiments. Capsaicin 100 micrograms was injected intradermally on the volar forearm followed by an i.v. infusion of ketamine (bolus 0.1 mg kg-1 over 10 min followed by infusion of 7 micrograms kg-1 min-1), lidocaine 5 mg kg-1 or saline for 50 min. ⋯ Lidocaine reduced the area of punctate-evoked hyperalgesia significantly. It tended to reduce VAS scores of spontaneous pain but had no effect on evoked pain. The differential effects of ketamine and lidocaine on static and dynamic hyperalgesia suggest that the two types of hyperalgesia are mediated by separate mechanisms and have a distinct pharmacology.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Effect of continuous epidural 0.2% ropivacaine vs 0.2% bupivacaine on postoperative pain, motor block and gastrointestinal function after abdominal hysterectomy.
We have investigated the effect of 24-h postoperative continuous epidural infusion of 0.2% ropivacaine or 0.2% bupivacaine 8 ml h-1 on pain, request for supplementary analgesics, motor block and gastrointestinal function, in a double-blind, randomized study in 60 patients undergoing open hysterectomy. There were no significant differences between groups in pain, number of patients requesting supplementary analgesics, motor block, ability to walk or time to first flatus or stool. In the subgroup of patients who received supplementary analgesics, patients in the ropivacaine group received significantly more ketorolac than patients in the bupivacaine group. Time to discharge from hospital was similar with ropivacaine and bupivacaine.
-
Case Reports
Thoracic paravertebral block: radiological evidence of contralateral spread anterior to the vertebral bodies.
We report contralateral spread of contrast medium anterior to the vertebral bodies after injection of contrast through a thoracic paravertebral catheter that was used to manage pain in a patient with multiple fractured ribs. We review the literature and propose that the anatomical basis for this observation is spread in the extrapleural compartment of the thoracic paravertebral space along the subserous fascial plane.
-
Randomized Controlled Trial Clinical Trial
EEG controlled rapid opioid withdrawal under general anaesthesia.
We performed rapid opioid detoxification under propofol anaesthesia in 30 opioid addicts, using the opioid receptor antagonist naltrexone. Two strategies to obtain a sufficient depth of anaesthesia and to avoid anaesthetic overdose were evaluated. Patients were allocated randomly to one of two groups. ⋯ There were significant differences in the total dose of propofol given (group 1, mean 72 (SD 9) mg kg-1; group 2, 63 (8) mg kg-1; P < 0.01), duration of anaesthesia (318 (53) min vs 309 (42) min; P < 0.05), duration of recovery time (49 (13) min vs 40 (12) min; P < 0.01) and frequency of withdrawal symptoms between groups. In addition, the incidence of side effects was different between groups (62 vs 29 points on a withdrawal symptom scale; P < 0.01). To obtain a sufficient depth of anaesthesia but to avoid inappropriately large doses of anaesthetic, we consider that EEG monitoring is valuable during rapid opioid detoxification.
-
We have investigated the effects of adenosine i.v. on neuromuscular block induced by rocuronium, vecuronium and pipecuronium in an in vivo guinea-pig sciatic nerve-tibialis anterior preparation. The ED50 of each neuromuscular blocker was determined from cumulative log dose-response regression lines (n = 14). In separate experiments, adenosine 0.1 mg kg-1 min-1 or the same volume of 0.9% NaCl was given i.v. via a constant infusion and the ED50 of each neuromuscular blocking agent was then administered (n = 24). ⋯ Time to maximal block after rocuronium was significantly prolonged by adenosine (1.4-2.1 min; P < 0.05) and time to maximal block after vecuronium and pipecuronium was unchanged by adenosine. Time to maximal recovery of twitch tension after administration of the ED50 of all neuromuscular blocking agents was prolonged significantly by adenosine (4.5-10.7 min, 8.2-15.8 min and 47.0-128.7 min, respectively, for rocuronium, vecuronium and pipecuronium; P < 0.05). We conclude that continuous infusion of adenosine 0.1 mg kg-1 min-1 potentiated the effects of neuromuscular blocking agents in this in vivo guinea-pig preparation.