Summary

Background and objective: Combined (local and general) anaesthesia or Balanced (intravenous analgesics and inhalational hypnotics) anaesthesia are commonly used in paediatrics. The authors have investigated the influence of both types of anaesthesia on the requirements of sevoflurane to maintain an adequate level of hypnosis as measured by Bispectral index (at around 50) monitoring in paediatric orthopaedic patients. Methods: Twenty-six orthopaedic surgery patients aged 2–15 yr were randomized to receive, during general sevoflurane anaesthesia, 5 μg kg−1 of intravenous fentanyl (Balanced anaesthesia group) or 1 mL kg−1 of caudal-epidural bupivacaine 0.25% (Combined anaesthesia group). The end-tidal sevoflurane concentration was adjusted every 5 min in order to maintain Bispectral index values at around 50. Results: Patients showed very similar Bispectral index values (P > 0.05) in both the Combined and the Balanced groups before anaesthesia (96.7 ± 2.7 vs. 96.9 ± 1.8), after induction (48.5 ± 2.9 vs. 49.8 ± 3.6) and after administration of analgesia (50.9 ± 3.8 vs. 50.3 ± 4.3). The sevoflurane end-tidal concentration requirements were similar in both the Combined and Balanced groups before administration of analgesia (2.1 ± 0.2 vs. 2.1 ± 0.4, P = 0.9415), but lower end-tidal concentrations were required by the Combined group than by the Balanced group (0.81 ± 0.4 vs. 1.5 ± 0.5, P < 0.0001) in the first 20 min after administration of analgesia. Conclusion: Combined anaesthesia with epidural bupivacaine maintains the same Bispectral index values as Balanced anaesthesia during orthopaedic surgery in children without fentanyl and with a lower sevoflurane requirement.

Summary

Background and objectives: To compare the analgesic effects of intrathecal fentanyl and low-dose intravenous ketamine as adjuvants to intrathecal bupivacaine for Caesarean section. Methods: Ninety elective Caesarean section patients were randomized into three groups. Spinal anaesthesia was performed with 15 mg hyperbaric bupivacaine in all groups. Ketamine (0.15 mg kg−1) or an equal volume of normal saline was given intravenously immediately after initiating spinal anaesthesia in the ketamine and control group, respectively. In the fentanyl group, 10 μg fentanyl was added to the intrathecal bupivacaine. Arterial pressures, heart rate values, adverse effects, the time of first request for postoperative analgesia, visual analogue pain scores, total analgesic consumptions at 24 and 48 h were recorded in all patients. Results: The time to first request for analgesia was significantly longer in the ketamine (197 min) and fentanyl (165 min) groups compared to the control group (144 min). Postoperative pain scores were significantly lower in the ketamine group than in both other groups. Although the analgesic requirements during first 24 h were significantly lower in the ketamine group, there was no significant difference between the groups during the following 24 h. Conclusion: Intravenous low-dose ketamine combined with intrathecal bupivacaine for Caesarean section provides longer postoperative analgesia and lower postoperative analgesic consumption than bupivacaine alone suggesting a pre-emptive effect.