British journal of anaesthesia
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Review Case Reports
Grand mal convulsion and plasma concentrations after intravascular injection of ropivacaine for axillary brachial plexus blockade.
We report a patient to whom ropivacaine 1.1 mg kg(-1) was administered for brachial plexus blockade and who developed grand mal convulsions because of inadvertent i.v. injection. No symptoms of cardiovascular toxicity occurred. ⋯ The measured total plasma concentrations of ropivacaine were 3.3, 1.6, 1.2 and 1.0 mg litre(-1) respectively. Initial plasma concentration after the end of the injection period was estimated at 5.75 mg litre(-1) using a two-compartment pharmacokinetic model.
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Randomized Controlled Trial Comparative Study Clinical Trial
Effects of minor surgery and endotracheal intubation on postoperative breathing patterns in patients anaesthetized with isoflurane or sevoflurane.
We studied the effects of minor surgery and endotracheal intubation on postoperative breathing patterns. We measured breathing patterns and laryngeal resistance during the periods immediately before intubation (preoperative) and immediately after extubation following minor surgery (postoperative) in eight patients anaesthetized with sevoflurane and eight patients anaesthetized with isoflurane, breathing spontaneously through a laryngeal mask airway at a constant end-tidal anaesthetic concentration (1.0 MAC). In both sevoflurane-anaesthetized and isoflurane-anaesthetized patients, expiratory time was reduced and inspiratory and expiratory laryngeal resistance increased after surgery. ⋯ Occlusion pressure did not change and T(I) was greater in isoflurane-anaesthetized patients after surgery. Minor surgery may have a small but significant influence on breathing and increased laryngeal resistance following endotracheal intubation may modulate these changes. The difference in breathing pattern between sevoflurane and isoflurane may be a result of different responses of the central nervous system to different anaesthetics in the presence of increased laryngeal resistance.
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Randomized Controlled Trial Comparative Study Clinical Trial
Influence of equianaesthetic concentrations of nitrous oxide and isoflurane on regional cerebral blood flow, regional cerebral blood volume, and regional mean transit time in human volunteers.
Nitrous oxide and isoflurane have cerebral vasodilatory effects. The use of isoflurane in neuroanaesthesia is widely accepted, whereas the use of nitrous oxide in neuroanaesthesia is still the subject of debate. In the present study, contrast-enhanced magnetic resonance (MR) perfusion measurement was used to compare the effects of 0.4 MAC nitrous oxide (n=9) and 0.4 MAC isoflurane (n=9) on regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV) and regional mean transit time (rMTT) in spontaneously breathing human volunteers. ⋯ Isoflurane, by contrast, increased rCBF and rCBV in basal ganglia more than did nitrous oxide. An increased rMTT was caused by a relatively greater increase in rCBV than in rCBF supratentorially by isoflurane and infratentorially by nitrous oxide. In conclusion, nitrous oxide increases rCBF and rCBV predominantly in supratentorial grey matter, whereas isoflurane increases rCBF and rCBV predominantly in infratentorial grey matter.
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We present a case of a probably unnecessary Caesarean section due to misinterpretation of the cardiotocography (CTG) trace during general anaesthesia. A 27-yr-old patient in her 30th week of an uneventful, normal first pregnancy presented with a deep venous thrombosis in the pelvic region. She was to undergo an emergency thrombectomy under general anaesthesia. ⋯ The pH at delivery was 7.23 and the baby was extubated 2 days later. Mother and child recovered without short-term sequelae. In the absence of alternative explanations, reduced fetal beat-to-beat variability with a normal baseline heart rate during general anaesthesia is probably normal.