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The aim of this study was to examine the performance of anaesthetists while managing simulated anaesthetic crises and to see whether their performance was improved by reviewing their own performances recorded on videotape. Thirty-two subjects from four hospitals were allocated randomly to one of two groups, with each subject completing five simulations in a single session. Individuals in the first group completed five simulations with only a short discussion between each simulation. Those in the second group were allowed to review their own performance on videotape between each of the simulations. Performance was measured by both 'time to solve the problem' and mental workload, using anaesthetic chart error as a secondary task. Those trainees exposed to videotape feedback had a shorter median 'time to solve' and a smaller decrease in chart error when compared to those not exposed to video feedback. However, the differences were not statistically significant, confirming the difficulties encountered by other groups in designing valid tests of the performance of anaesthetists.

Although many anaesthesia machines are equipped with circle rebreathing systems, inhalational anaesthesia remains frequently performed using relatively high fresh-gas flows. The major advantages of rebreathing techniques can be achieved only if the fresh-gas flow is reduced to 1 l.min-1 or less. Although there are potential risks associated with low-flow anaesthesia, modern anaesthesia machines meet all the technical requirements for the safe use of low-flow techniques if they are used in conjunction with equipment for monitoring inhaled and exhaled gas concentrations; these monitors are already increasingly available and, in the near future, are likely to become an obligatory safety standard in many countries. For both economic and ecological reasons, the use of new inhalational anaesthetics, with low tissue solubility and low anaesthetic potency, can be justified only if the efficiency of administration is optimised by using low-flow anaesthetic techniques.

Fifty ASA 1 or 2 patients scheduled to undergo major gynaecological surgery were allocated randomly to one of two groups. All patients received a standard anaesthetic regimen. Patients in group 1 received droperidol 1.25 mg given intravenously 20 min prior to the end of surgery and a patient-controlled analgesia infusion containing morphine 1 mg.ml-1 and droperidol 0.05 mg.ml-1. Patients in group 2 received cyclizine 50 mg by slow intravenous injection 20 min prior to the end of surgery and a patient-controlled analgesia infusion containing morphine 1 mg.ml-1 and cyclizine 2 mg.ml-1. Fifteen of 25 patients (60%) in group 1 and 18 (72%) of 25 in group 2 suffered no nausea or vomiting postoperatively. Two patients (8%) in group 1 and three (12%) in group 2 suffered severe postoperative nausea or vomiting. We conclude that cyclizine is as effective as droperidol in the prevention of postoperative nausea and vomiting when included in a patient-controlled analgesia infusion using morphine.

A questionnaire study was undertaken to assess the influence of recently published, simple and conclusive research on the practice of anaesthetists in four centres. The research had clearly demonstrated the benefit of subcutaneous infiltration of local anaesthetic in reducing the pain of intravenous cannulation. Of the 81% who responded, 71% were aware of the research; 43% of these anaesthetists had altered their clinical practice as a result of the research and 73% used local anaesthesia for cannulae of 18 gauge or less, compared with only 46% of those who were unaware of the research. Practice comparisons were made between centres and grades of anaesthetist. Senior house officers were significantly less likely to be aware of the research than other grades. Anomalies were identified between the apparent awareness of the research and routine practice agreeing with the study findings. The value of research and the incorporation of clinical findings into everyday practice is discussed.

We performed a prospective study in our teaching hospital to determine the demand for a High Dependency Unit where none had existed before. An admission criteria protocol was designed for medical and surgical patients and this was used in an intense surveillance of 22 acute wards over 2 weeks. It was predicted that a high dependency unit of eight beds would operate to capacity 50% of the time. An analysis of this type over a short period of time using similar admission criteria could be used to assist in the prediction of the necessary size of a High Dependency Unit facility in any hospital.

Tussometry involves a continuous measurement of airflow produced by a cough manoeuvre displayed as an airflow-time wave. There is a rapid rise to its peak (cough peak flow rate) and the time taken to reach the peak (peak velocity time) is determined by the laryngeal opening at the onset of cough. Cough peak flow and peak velocity time were measured in 10 healthy volunteers before and after topical anaesthesia of the larynx with lignocaine 100 mg sprayed under indirect laryngoscopy. Adequacy of anaesthesia was established by touching the cords deliberately with a fibreoptic laryngoscope. All subjects had excellent anaesthesia of the larynx. However, cough peak flow rate and peak velocity time remained unchanged following topical anaesthesia. We conclude that topical anaesthesia of the larynx does not impair the motor performance of the vocal cords during a voluntary cough.

A double-blind, randomised, controlled trial was performed to assess the antiemetic efficacy of metoclopramide when included in a morphine patient-controlled analgesia regimen. Fifty ASA grade 1 or 2 patients scheduled for elective intermediate or major gynaecological surgery were allocated into one of two groups. All patients received a standardised anaesthetic and metoclopramide 5 mg was given intravenously 10 min before the end of the procedure. Group 1 received a patient-controlled analgesia regimen using morphine 1 mg.ml-1 solution. Group 2 received a patient-controlled analgesia regimen using morphine 1mg.ml-1 with metoclopramide 0.5 mg.ml-1 solution. Postoperative antiemetic treatment was with metoclopramide 10 mg intramuscularly or cyclizine 50 mg intramuscularly if this was ineffective. Pain scores, sedation scores, and morphine requirement were not significantly different between the groups. There was no difference in nausea scores between the groups, but more patients suffered moderate or severe nausea in group 1 (10 patients) than group 2 (three patients, p < 0.026). We conclude that metoclopramide, when included in a patient-controlled analgesia regimen, reduces the incidence of moderate to severe nausea, but not the overall incidence of nausea.

Ten healthy volunteers were placed in three different surgical prone positions (knee-chest, Eschmann frame and two supports, one each for the thorax and pelvis); the normal prone position without any supports was used as a control. Lung volumes using helium dilution and spirometry were calculated for each volunteer in each position. Compared with the control position, functional residual capacity, expiratory reserve volume, residual volume and total lung capacity were significantly higher in the knee-chest position. Functional residual capacity and expiratory reserve volume were significantly higher in the frame position. No advantage was gained with the use of the two supports position. We conclude that, of these three prone positions in awake volunteers, the knee-chest position causes least respiratory restriction.

The effect of the addition of a single dose of 7 micrograms.kg-1 of alfentanil to a propofol/enflurane anaesthetic on the quality of anaesthesia and recovery was assessed. A total of 53 ASA grade 1 or 2 patients who underwent daycase dental surgery were allocated randomly to receive either alfentanil or saline. The study was blinded so that neither the anaesthetist nor the assessor was aware of which solution had been given. Patients in the alfentanil group took significantly longer to recommence spontaneous ventilation (p = 0.035). Both techniques provided good quality of anaesthesia. Postoperative morbidity was common (45% of patients), but there was no difference between the groups. The rate of recovery was similar in the two groups and no patient required hospital admission after the final assessment at 3 h. Drowsiness was only mild to moderate in both groups at 24 h. A single dose of alfentanil can be administered safely as part of a daycase anaesthetic without increasing morbidity, although there appears to be little advantage in doing so.

Fifty-seven healthy female patients who underwent gynaecological laparoscopic surgery received either desflurane or propofol for induction and maintenance of anaesthesia. Inhalational induction was generally well tolerated, and consciousness was lost in approximately 2 min (mean end-tidal concentrations of desflurane were 8.3% with 60% nitrous oxide, and 7.1% with oxygen). Recovery of consciousness and orientation were more rapid in patients in whom anaesthesia was maintained with desflurane than with propofol, but there were no differences in psychomotor function test scores at 30 min. The data suggest that desflurane provides controllable anaesthesia and rapid recovery of consciousness after laparoscopic surgery.

Two groups of adult patients (55 each) were visited pre-operatively by an anaesthetist who was dressed either formally or casually. Their response to this visit, their opinions regarding anaesthetists and their knowledge of anaesthetic work were elicited afterwards by means of a questionnaire. Patients' satisfaction with the anaesthetist and his/her visit was not influenced by dress. The anaesthetist was awarded a high level of prestige and the length of his/her training was recognised to be comparable to that of other professionals; 81.8% of patients thought that anaesthetists held a medical degree but only 35.4% thought that they worked in the intensive care unit. Patients expressed a preference for doctors to wear name tags, white coats and short hair but disapproved of clogs, jeans, trainers and earrings.

One thousand patients who were anaesthetised between February and April 1990 at University Hospital, Nottingham were interviewed between 20 and 36 hours after their operation. Patients under 16 years of age, those who had undergone obstetric or intracranial surgery, those who were unable to communicate and patients who were discharged from hospital before the postoperative visit were not interviewed. A standard set of questions was used to determine the incidences of recall of events and dreams during the operation. These incidences were 0.2% and 0.9% respectively, considerably lower than reported in previous comparable studies.

This retrospective study found that the long-term (greater than 6 months) postoperative survival in ASA 4E and 5E patients was 41% and 21% respectively, in 1986. This supports the Confidential Enquiry into Peri-operative Deaths' recommendation that life-saving surgery should not be withheld from patients who present in so serious a condition that they are unlikely to survive surgery.

Sixty-nine patients undergoing upper and lower abdominal surgery were studied after operation to compare the analgesic effects of sublingual buprenorphine (0.4 mg) and slow release morphine sulphate tablets (MST, 20 mg) given 6 hourly in a double-blind, double-dummy trial. Both MST and buprenorphine produced satisfactory postoperative analgesia but the linear analogue pain scores were significantly lower on the second post operative day with MST.

A model lung system with a variable artificial constriction was used to quantify the changes in flow produced by the addition of helium to the gas mixture in the system. The tracheal concentration of helium obtained when administering 79% helium/21% oxygen to the system via conventional, disposable face masks was determined using a resuscitation dummy. The greatest proportion of the increase in flow through the orifice occurred at concentrations of helium up to 40%. A tracheal concentration of 40% helium could be obtained with all oxygen masks at fresh gas flow rates greater than 8 litres/minute. These findings will help to rationalise the administration of 79% helium/21% oxygen to patients with upper respiratory tract obstruction.

Indentation of the dura has been proposed as the cause of subatmospheric pressure in the extradural space, but has never been demonstrated directly in humans. In this study, radiographs have been produced showing dimpling of the dura by a needle tip lying in the extradural space in the dog. Pressure tracings demonstrate that advancement of the needle tip produces a progressive decrease in extradural pressure, and observations made using an image intensifier have confirmed that the pressure changes are proportional to the degree of dural indentation.