Summary Key wordsAnaesthesia; obstetric. Anaesthetic techniques; epidural. Intravenous jluids; Hartmann's, polygelatin (Haemaccel).The many advantages of conduction anaesthesia over general anaesthesia for Caesarean section have been well described by Moir' and the continuing high incidence of deaths from Mendelson's syndrome, failed intubation and hypoxia associated with general anaesthesia2 fuels the present enthusiasm for performing Caesarean sections using epidural analgesia. Conduction anaesthesia, however, poses its own problems, of which hypotension and inadequate analgesia are the most relevant. For adequate analgesia a high block, to at least T6, is necessary and the concomitant vasodilatation predisposes to hypotension, even when great care is taken to avoid aortocaval compression.A widely used method of prophylaxis against hypotension developing during conduction anaesthesia for Caesarean section has been an intravenous preload of 1 litre of crystalloid solution 30 minutes before establishing the nerve block,3 but this has failed to be consistently effective in our experience and that of other^.'^ It was, therefore, decided to invesiigate the incidence of hypotension occurring in patients undergoing Caesarean section with epidural analgesia, preloaded with either intravenous colloid or crystalloid solutions.

SummarySixty patients received either alfentanil. halothane or enjlurane .for maintenance of anaesthesia during short day-case gynaecological procedures. The alfentanil group recovered more rapid1.v but there wus no difference between haloihane und enflurane in lerms of recovery time. Apnoea and movement during surgery only occurred in the patienis who received al/entanil. The incidence of other side effects was the same in each group, including late subjective feelings of drowsiness and unsteadiness Key wordsAnaesthetics, gases; enflurane, halothane. Anaesrhetics. intravenous; alfentanil.Alfentanil is a relatively new opiate analgesic with rapid onset of action, short duration of effect and apparently little accumulation when given by repeated injections.' These properties would seem to make alfentanil an ideal agent for short procedures. The recovery time and adverse side-effects of alfentanil were therefore compared to those following anaesthesia with enflurane or halothane. MethodsSixty female patients over the age of 16 years and who weighed between 40-90 kg were included in the study. All attended the gynaecology day-case unit for minor procedures which involved dilatation of the cervix but not involving any skin incision.The patients were randomly allocated to three groups and referred to as Group A (alfentanil), Group H (halothane) and Group E (enflurane).Local ethical approval was obtained, and all patients gave informed consent. Each patient received temazepam 20 mg orally I hour pre-operatively as premedication. Group A received alfentanilO.5 mg at induction by slow intravenous injection followed by methohexitone I % 1 ml every 5 seconds until abolition of the eyelash reflex. Anaesthesia was maintained with nitrous oxide and oxygen (70% :30%) together with increments of alfentanilO.2 mg or methohexitone I ml as indicated clinically. Indications for alfentanil increments were taken as: sweating, lacrimation, increased rate and depth of respiration, minor movement, and the anaesthetist's anticipation of surgical dilatation of the cervix. Gross movement was regarded as an indication for further methohexitone. Group H and Group E both received methohexitone I YO at induction at the rate of I ml every 5 seconds until abolition of the eyelash reflex. Anaesthesia was maintained with 70% N,0/30% 0, plus sufficient halothane or enflurane to produce surgical anaesthesia. No further increments of methohexitone were given to either of these groups.Note was made of the time when the first dose of alfentanil or methohexitone was given at induction, the time that surgery commenced, the time that any increments of drugs were given and the time that all anaesthetic gases were switched off.