British journal of anaesthesia
-
It has been suggested previously that tramadol increases central nervous system activity and 'lightens' anaesthesia with volatile agents. We assessed the effects of tramadol on the minimum alveolar concentration (MAC) of isoflurane in 56 Wistar rats, instrumented chronically with an arterial and central venous catheter. The MAC of isoflurane was determined using the tail clamp method under three conditions: (1) after injection of saline (control); (2) after administration of tramadol 10 mg kg-1 i.v.; and (3) after administration of morphine 1 mg kg-1 i.v. ⋯ In contrast, after pretreatment with naloxone, tramadol (1.47 (0.04)%) or morphine (1.38 (0.07)%) did not cause a reduction in the MAC of isoflurane compared with controls (1.39 (0.06)%). We conclude that tramadol and morphine reduced the MAC of isoflurane to a small but significant extent. For both drugs, this effect was related to their action at opioid receptors.
-
Randomized Controlled Trial Multicenter Study Comparative Study Clinical Trial
Comparison of 0.25% S(-)-bupivacaine with 0.25% RS-bupivacaine for epidural analgesia in labour.
We have compared the efficacy of 0.25% S(-)-bupivacaine with 0.25% RS-bupivacaine in providing epidural analgesia for labour in a randomized, multicentre, double-blind study. Analgesia was initiated with 10 ml of the study solution and maintained with 10-ml top-ups. We studied 137 women and treatments were found to be equivalent for onset, duration and quality of block. ⋯ However, median duration of pain relief from the first top-up was 82 (range 3-164) min for S(-)-bupivacaine and 76 (22-221) min for RS-bupivacaine. There were no significant differences in the quality of analgesia, as assessed by the investigators. There were no significant differences in the extent of sensory block, percentage of patients with motor block or incidence of adverse events.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Ondansetron and droperidol in the prevention of postoperative nausea and vomiting.
We have performed a prospective, randomized, double-blind clinical study to assess the efficacy of ondansetron, droperidol, or both, in preventing postoperative emesis. We studied 242 patients undergoing biliary or gynaecological surgery under general anaesthesia. ⋯ Groups 2 and 4 had greater sedation scores than group 1 during the first 3 h (P < 0.01). We conclude that both droperidol and ondansetron showed a significant antiemetic effect, ondansetron was not significantly better than droperidol, and the combination of droperidol and ondansetron was better than droperidol but no better than ondansetron alone.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of low-dose epidural with combined spinal-epidural analgesia for labour.
We have performed a randomized comparison of two low-dose epidural regimens for analgesia in labour, differing only in the manner in which initial analgesia was established. In the epidural (EPI) group, 484 women received a loading dose of 20 ml of 0.1% bupivacaine with fentanyl 2 micrograms ml-1. In the combined spinal-epidural (CSE) group, 524 women received a spinal injection of plain bupivacaine 2.5 mg with fentanyl 25 micrograms. ⋯ Other comparisons between groups revealed no differences. These findings may have been affected by an uneven distribution of multiparous women between the groups (25% in the EPI group and 34.2% in the CSE group; P = 0.002). However, subgroup analysis of primiparous and multiparous women did not alter the results.