Subarachnoid anaesthesia was induced in 40 patients with 0.5% bupivacaine 3 ml with no glucose, 5% glucose or 8% glucose, or with hyperbaric cinchocaine . The injections were made in the lateral position and the patients turned supine immediately. The onset, extent and duration of sensory and motor blockade, the quality of anaesthesia, cardiovascular effects, and the frequency of side-effects were studied. The hyperbaric solutions produced a greater cephalad spread (T6-T7) than the glucose-free solution (T10-T11). Cinchocaine produced a longer duration of action at T10 and T12 than the hyperbaric bupivacaine solutions. No advantage was seen when 8% rather than 5% glucose was used. The glucose-free bupivacaine produced intense blockade of long duration and was suitable when a lower level of blockade was adequate for the proposed surgery.

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An anaesthetic agent suitable for use in prolonged out-patient dental restoration work for unpremedicated, hyperactive children must be safe, have a rapid onset of action, provide satisfactory operating conditions, and allow a quick and complete recovery.The aim of this study was to ascertain whether ketamine would fulfil these criteria and possibly also have other advantages, including the avoidance of hypotension, and only cause minimal depression of pharyngo-laryngeal reflexes. It was also hoped that it would prove easy to administer and that there would be no need for endotracheal intubation.The use of ketamine for out-patient oral surgery procedures has been described by other workers.'-3 This study was confined t o children under the age of 12 years in view of the reported incidence of emergence phenomena in adolescents and adult patients. MethodsThirty-one children between the ages of 4 and 1 1 years were studied. Eleven had dental conservation alone, eighteen conservation and extractions, and two dental pulpectomy only.Pre-operative assessment. A medical history, physical examination, record of weight and a haernoglobin were undertaken at the same visit as the dental assessment. In addition, a sickle cell test was performed on those children of negroid extraction. haestlietic technique. Atropine 0.6 nig with a small sip of water was given orally to ten patients, and intravenously on induction in one patient. All patients were induced in the sitting position. Ketamine, 10 mg/kg of loo,/, solution, was administered intramuscularly into the deltoid muscle in three cases, and 1 mgikg of 1 y i solution intravenously in twentyeight cases.Several minutes after intramuscular injection and within 30 seconds of intravenous administration, the patients were sufficiently anaesthetised to allow the insertion of a mouth prop and for the oro-pharynx to be packed off.The jaw was supported during the operative procedure in order to maintain the airway when the dentist exerted pressure, and the dental assistant was encouraged t o perform frequent oral suction.

Patients admitted for daycase surgery pose particular problems for the anaesthetist. In common with all paticnts who await surgery. they suffer from a variety of dcgrees uf fear and anxiety. The administration of appropriate prcrnedicalion would hclp to allay such anxiety and also reduce the doscs of anaesthetic agents required both to induce and maintain anaesthesia. The short-acting anxiolytic agent temazepam has been shown to allay anxiety and to reduce anaesthetic requirement and postoperative morbidity without prolonging recovery time.' ,z Howcvcr. there are logistical difficulties associated with the organisation of oral premedication for patients who may be admitted to a busy day-surgery ward only a short time before the induction of anaesthesia. It has become common practice in our hospital for such patients to be given small doses of midazolam and alfentanil prior lo induction of anaesthesia. in the hope that this pretreatment might reduce the dose o f induction agent necessary and thus provide a shorter and more pleasant recovery. Such an outcome would have potential advantages in that postopcrativc morbidity might be reduced, and a more rapid turnover of paticnts might result. with more efficient use of beds. We therefore conducted a study to examine the quality of anaesthesia and rccovery in paticnts who were scheduled to undergo daycase arthroscopy. and who were either pretreated with a combination of mida~olam and alfentanil or received alfentanil alone. Patients and methodsOnc hundrcd patients between thc ages of 15 and 63 years who were admitted to the day unit for arthroscopic cxamination and in some cases arthroscopic surgery of the knee. took part in the study which was approved hy the local ethical committee. All the patients were fit apart from their orthopaedic condition and all gave informed consent.The paticnts werc allocated randomly to onc of two groups; a midazolam group (Group M ) and a saline group (Group S ) . A 23-gauge cannula was inserted into an antecuhjtal fossa vein when the patient arrived in the anaesthetic room, and 500 pg of alfentanil was administered either with midarolam 5 mg (Group M) or I ml o f sodium chloride 0.9% (Group S ) . The midazolam and saline were prepared in unmarked coded ampoules and the anaesthetist was not aware which solution was bcing given. Exactly 2 minutes after this injection, the patients received a dose of methohexitone 1 % given at a rate of I ml per 3 seconds until the eyelash reflex was obtunded. The dose of meth-~ Pringle, MD. MRCS, LRCP, DCH, FFARCS, Consultant,

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