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The pharmacokinetics of nalbuphine were studied in 10 healthy volunteers on two separate occasions following administration by either the intravenous (20 mg) or oral (60 mg) route. After administration, serum concentrations of nalbuphine were measured for 12 h using a high pressure liquid chromatography assay, and pharmacokinetic parameters were derived using a three compartment model. After i.v. administration, elimination half-life was 222 (111-460) min (mean and range) and total body clearance was 1.5 (0.8-2.3) 1 min-1. Cmax after oral administration was 21.4 (6.0-36.2) ng ml-1 and tmax was 46.6 (15.3- 89.0) min. Bioavailability of the oral preparation was 11.8 (6.1-20.1)%. [ABSTRACT FROM AUTHOR]

Public expectations of healthcare have changed dramatically over the last 10-20 years, particularly in relation to the involvement of patients in determining treatment options and the selection of the most appropriate treatment plan. Paternalistic actions of doctors, which involved telling the patient what treatment they were going to receive, without discussing risks and benefits of various options, are no longer acceptable. This has been reflected in decisions reached by the courts in cases in which patients have entered litigation on the basis that inadequate information was given to them before treatment, and that they were unaware of risks of complications which subsequently materialised. If such claims are successful, the patient is entitled to financial compensation even if the treatment was carried out to the highest standard. Although most claims of this nature are brought against surgeons, similar claims are likely in relation to anaesthetic procedures. Complaints about lack of information or inadequate consent can also result in a doctor being reported to regulatory authorities. It is therefore necessary for anaesthetists to be aware of current issues surrounding provision of information and obtaining consent for anaesthesia in various categories of patient. This article summarises these issues.

General anaesthesia in 12 pregnant ewes undergoing surgery for fetal physiological research was supplemented with an intravenous infusion of remifentanil. This allowed us to employ a lighter plane of surgical anaesthesia and to use intermittent positive pressure ventilation. Our aim was to improve fetomaternal outcome. We monitored maternal pulse, blood pressure, transcutaneous oxygen saturation and end-tidal carbon dioxide levels. Remifentanil doses of 0.75-2.0 microg/kg/min were needed and typically this allowed halothane concentrations of 1-1.5% to be used for maintenance of anaesthesia. Surgery lasted up to 2.5 h. All 12 ewes and their singleton fetuses survived the peri- and postoperative period in good condition.

Unlabelled: We present an original, mathematical model of ventilation and gas-exchange. Our aim was to validate it using data from previous clinical investigations, allowing our use of it in future investigations. The first previous investigation used a low-dead space, double-lumen, tracheal tube (DLT). We matched the model's PaCO(2) and airway pressures (P(AW)) to the patient mean during use of the DLT and a single-lumen tube (SLT). The model's resulting PaCO(2), PECO(2) and P(AW) were compared with the patients' as tidal volume (VT) changed with constant minute volume. The second investigation examined dead space during anesthesia. The model's VT, respiratory rate, CO(2) production, temperature, and alveolar and anatomical dead spaces were matched to each mechanically ventilated subject. Bias and precision in predictions of PaCO(2) and PECO(2) were calculated. The model's bias in prediction of dead space reduction by the DLT was 6.9%. Bias in prediction of P(AW) was 0.1% (peak) and -5.13% (mean), of PaCO(2) was 1.2% (DLT) and 1.5% (SLT) and of PECO(2) was 1.7% (DLT) and 1.3% (SLT). Prediction of PaCO(2) and PECO(2) in the second investigation (as 95% confidence interval of bias): PaCO(2) -2.6% to 0.8% and PECO(2) -4.9% to 1.2%. This validation allows future application of our model in appropriate theoretical investigations., Implications: We present an original, mathematical model of ventilation and gas exchange. We validate it against previously published clinical data to allow its use in future theoretical investigations where data may be unavailable from patients.

Unlabelled: Using an original, validated, high-fidelity model of pulmonary physiology, we compared the arterial to end-tidal CO(2) gradient divided by the arterial CO(2) tension (Pa-E'CO(2)/PaCO(2)) with alveolar dead space expressed as a fraction of alveolar tidal volume, calculated in the conventional manner using Fowler's technique and the Bohr equation: (VDalv/VTalv)(Bohr-Fowler). We examined the variability of Pa-E'CO(2)/PaCO(2) and of (VDalv/VTalv)(Bohr-Fowler) in the presence of three ventilation-perfusion defects while varying CO(2) production (Vdot;CO(2)), venous admixture, and anatomical dead space fraction (VDanat). Pa-E'CO(2)/PaCO(2) was approximately 59.5% of (VDalv/VTalv)(Bohr-Fowler). During constant alveolar configuration, the factors examined (Vdot;CO(2), pulmonary shunt fraction, and VDanat) each caused variation in (VDalv/VTalv)(Bohr-Fowler) and in Pa-E'CO(2)/PaCO(2). Induced variation was slightly larger for Pa-E'CO(2)/PaCO(2) during changes in VDanat, but was similar during variation of venous admixture and Vdot;CO(2). Pa-E'CO(2)/PaCO(2) may be a useful serial measurement in the critically ill patient because all the necessary data are easily obtained and calculation is significantly simpler than for (VDalv/VTalv)(Bohr-Fowler)., Implications: Using an original, validated, high-fidelity model of pulmonary physiology, we have demonstrated that the arterial to end-tidal carbon dioxide pressure gradient may be used to robustly and accurately quantify alveolar dead space. After clinical validation, its use could replace that of conventionally calculated alveolar dead space fraction, particularly in the critically ill.

Education is a core activity of academic departments but pressure from universities to maximize research income and research productivity, and from hospitals to deliver a more efficient clinical service, has pushed the importance of education into third place in many departments. Academic departments of anaesthesia can make significant contributions to undergraduate teaching. Students appreciate the one-to-one teaching which they receive from anaesthetists and the range of practical skills which they can learn. The main teaching burden of an academic department of anaesthesia relates to education of clinical trainees. National curriculum requirements must be delivered. Organization of a structured training programme, together with the appraisal and assessment systems which are necessary to ensure satisfactory progress of each trainee, require supervision by a number of academic staff, as well as administrative support. Higher postgraduate degrees may be gained by teaching or a combination of teaching and research. Teaching methods are changing, and there are opportunities to exploit e-learning on Intranet sites, and anaesthesia simulators, in both undergraduate and postgraduate education. Clinical governance issues and increasing scrutiny by authorities which fund teaching or set professional standards have resulted in demands for evidence that educational objectives are being met and that assessment systems are robust. There is a recognition that education has a cost, and resources are available from universities and hospitals to support the teaching activities of academic departments of anaesthesia.

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.

Unlabelled: The aim of our study was to validate the Nottingham Physiology Simulator (NPS) for examining pulmonary denitrogenation and apnea by reproducing the methodology and results of previous clinical studies. Only four studies provided sufficient detail in their description of their methodology to allow accurate reproduction by using the NPS or provided a sufficiently detailed description of their subjects to allow accurate modelling. The results of the NPS recreation of the studies were within 13% of the values found clinically in all cases and were within 2% in the majority of cases. The four studies included healthy and morbidly obese patients, conscious and anesthetized patients, and included examination of the effect of denitrogenation and apnea on plasma pH and on lung and arterial oxygen and carbon dioxide tensions at various lung volumes., Implications: We used mathematical, physiological models to recreate the methods and subjects of four clinical studies investigating oxygenation and low oxygen levels during cessation of breathing. Our aim was to validate the models, allowing theoretical investigations into this area. The blindly recreated results closely matched the clinical studies, validating the models.

Unlabelled: We used the Nottingham Physiology Simulator to examine the onset and course of hypoxemia during apnea after pulmonary denitrogenation. The following factors, as possible determinants of the hypoxemia profile, were varied to examine their effect: functional residual capacity, oxygen consumption, respiratory quotient, hemoglobin concentration, ventilatory minute volume, duration of denitrogenation, pulmonary venous admixture, and state of the airway (closed versus open). Airway obstruction significantly reduced the time to 50% oxyhemoglobin saturation (8 vs 11 min). Provision of 100% oxygen rather than air to the open, apneic patient model greatly prolonged time to 50% oxyhemoglobin saturation (66 vs 11 min). Hemoglobin concentration, venous admixture, and respiratory quotient had small, insignificant effects on the time to desaturation. Reduced functional residual capacity, short duration of denitrogenation, hypoventilation, and increased oxygen consumption significantly shortened the time to 50% oxyhemoglobin saturation during apnea., Implications: Reduction in oxygen levels during cessation of breathing is dangerous and common in anesthetic practice. We used validated, mathematical, physiological models to reveal the impact of physiological factors on the deterioration of oxygen levels. This study could not be performed on patients and reveals important information.

The alveolar deadspace as a fraction of alveolar ventilation (VDalv/VTalv), while technically difficult to measure, is an objective monitor of pulmonary disease progression and a predictor of successful weaning from mechanical ventilation. The aim of the study was to examine the relationship between the arterial to end-tidal PCO2 gradient (Pa-E'CO2) and VDalv/VTalv and between (Pa-E'CO2)/PaCO2 and VDalv/VTalv using the Nottingham Physiology Simulator, an original, validated physiology simulation. The relationships were observed while pulmonary shunt, anatomical deadspace, ventilatory minute volume and metabolic rate were varied. The relationship between Pa-E'CO2 and VDalv/VTalv was non-linear and was affected significantly by all the factors except anatomical deadspace. The relationship between (Pa-E'CO2)/PaCO2 and VDalv/VTalv (best fit: VDalv VTalv = 1.135 x (Pa-E'CO2)/PaCO2-0.005) during normal physiological conditions was approximately linear and less influenced by physiological variation. Shunt and anatomical deadspace caused some inaccuracy, although they are unlikely to prevent the clinical usefulness of this formula.

We aimed to validate the mathematical validity and accuracy of the respiratory components of the Nottingham Physiology Simulator (NPS), a computer simulation of physiological models. Subsequently, we aimed to assess the accuracy of the NPS in predicting the effects of a change in mechanical ventilation on patient arterial blood-gas tensions. The NPS was supplied with the following measured or calculated values from patients receiving intensive therapy: pulmonary shunt and physiological deadspace fractions, oxygen consumption, respiratory quotient, cardiac output, inspired oxygen fraction, expired minute volume, haemoglobin concentration, temperature and arterial base excess. Values calculated by the NPS for arterial oxygen tension and saturation (PaO2 and SaO2), mixed venous oxygen tension and saturation (PvO2 and SvO2), arterial and mixed venous carbon dioxide tension (PaCO2 and PvCO2) and arterial pH were accurate compared with measured values. Subsequently, arterial gas responses to changes in minute volume of FiO2 were measured in 31 patients and were compared with the NPS prediction for each response. The 95% limits of agreement in predicting the magnitude of change were: arterial oxygen tension -2.07 to 2.47 kPa; PaCO2 -0.33 to 0.67 kPa; and pH -0.023 to 0.033. This investigation has validated respiratory components of the NPS. We recommend the NPS as a clinical tool for predicting the effects of alterations in mechanical ventilation in stable patients in the intensive care unit.

We studied 10 patients undergoing laparoscopic cholecystectomy (group 1) and five control patients (group 2). We measured heart rate, arterial pressure, right atrial pressure (RAP), cardiac index (CI), systemic vascular resistance index (SVRI), intrathoracic pressure (ITP), plasma osmolality, adrenaline, noradrenaline and arginine vasopressin (aVP) concentrations, and serum renin activity (SRA), and calculated the atrial transmural pressure gradient (ATPG). We recorded significant decreases in mean arterial pressure (MAP), SVRI and CI in both groups (P < 0.05) after induction of anaesthesia. MAP and SVRI increased (P < 0.01) while CI decreased further in group 1 patients during the pneumoperitoneum. In group 1 plasma aVP concentration increased after insufflation of the pneumoperitoneum to a level sufficient to cause the recorded haemodynamic changes. ATPG decreased in group 1 patients during the pneumoperitoneum and this is a recognized trigger for aVP release.

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.

The differences in phonation between men and women are thought to occur from anatomical differences in the larynx. However, it is not known if there are any differences in cough dynamics between the sexes. We investigated this by asking 100 healthy, non-smoking adults (50 male) to perform a voluntary cough into a tussometer. Each volunteer coughed at four different lung volumes, ranging from total lung capacity to functional residual capacity. There was a positive correlation between peak velocity time and cough peak flow rate in both males (r = 0.73, P < 0.001) and females (r = 0.78, P < 0.001). Multiple regression analysis showed that height (P < 0.05) and sex (P < 0.001) were significant determinants of the relationship between peak flow rate and peak velocity time. In a height-matched subgroup, sex differences remained significant (P < 0.05). This may be related to anatomical differences in laryngeal structure and may have implications when using tussometry to assess laryngeal function.

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.

Tussometry is a new non-invasive technique for objectively assessing laryngeal function by analysis of the airflow waveform produced by a maximum effort voluntary cough manoeuvre. We describe the technique and present the calibration data. The tussometer has been calibrated for flows of up to 1100 litre min-1 using a flowmeter with a quoted accuracy of +/- 1.75%. The variables measured (cough peak flow rate (CPFR) and peak velocity time (PVT)) were found to be reproducible; the within-subject variability for CPFR was found to be 23.9% and for PVT 9%. There was no inter-observer variation. We found that the size of the mask used did not influence the readings obtained, providing an adequate seal was achieved.

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.

Tussometry is a new non-invasive method of assessing laryngeal function by analysing the airflow waveform produced by a voluntary cough. Ten healthy male volunteers performed five (n = 6) or six (n = 4) voluntary cough manoeuvres at varying lung volumes from total lung capacity to functional residual capacity. During each manoeuvre, airflow (litre min-1) was plotted against time (ms) to record the peak flow generated by the cough (CPFR) and the time taken to achieve this (PVT). In addition, expired volume (CEV) was measured during each manoeuvre. Highly significant (P < 0.001) correlations existed between CPFR and PVT (r = 0.81), CPFR and CEV (r = 0.78) and PVT and CEV (r = 0.71). We conclude that PVT may vary with CPFR which in turn bears a direct relationship to expired lung volume during a cough manoeuvre. These relationships among different variables should be considered when interpreting the results of tussometry.

We questioned whether the side effects outweighed the advantages of priming doses of nondepolarizing neuromuscular relaxants in awake patients. We have assessed lung function and clinical evidence of muscle weakness in 10 elderly patients, eight women and two men, aged 67-78 yr, ASA grade I or II, before and 3 min after a priming dose (0.01 mg/kg) of vecuronium. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), maximum midexpiratory flow rate (MMEF), peak expiratory flow rate (PEFR), inspiratory capacity (IC), functional residual capacity (FRC), expiratory reserve volume (ERV), residual volume (RV), slow vital capacity (SVC), and total lung capacity (TLC) were measured by using a Morgan transfer test machine and oxygen saturation (SpO2) was measured by pulse oximetry. All the patients developed ptosis, six had diplopia and were unable to perform the Valsalva maneuver for 10s, and four were unable to swallow or lift their head for > 4s, demonstrating significant muscle weakness. Significant reductions occurred in FVC, FEV1, FRC, ERV, SVC, and TLC. SpO2 decreased in 8 of 10 patients, and in 4 the decrease exceeded 4%. We conclude that priming with vecuronium 0.01 mg/kg in elderly patients causes significant impairment of lung function and a significant decrease in oxygen saturation.

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.

In a double-blind, randomized study, we have examined the influence of positive therapeutic suggestions, presented to anaesthetized patients undergoing total abdominal hysterectomy, on postoperative morbidity and duration of hospital stay. Seventy-five patients were allocated randomly to be exposed to one of three tapes containing positive therapeutic suggestions, a modified history of the Queen's Medical Centre, or no message. We found that neither therapeutic suggestions nor the presence of a voice during anaesthesia improved postoperative outcome or reduced duration of hospital stay after total abdominal hysterectomy.

We have assessed postoperative pain in 50 patients who had undergone total abdominal hysterectomy, using repeated contemporaneous and single retrospective visual analogue scores. There were significant correlations between the median, mean and greatest contemporaneous scores, and the single retrospective scores, but there was a wide scatter of results among and within individual patients. We conclude that the wide variability between the two methods of assessment suggests that the two techniques should not be used interchangeably.

A simple method for the simultaneous determination of morphine and its pharmacologically active metabolite morphine-6-glucuronide in 0.5 ml human plasma is described. It is based on the method of Svensson [J. Chromatogr., 230 (1982) 427 and 375 (1986) 174], but uses only one solid-phase extraction cartridge prior to chromatography and only a 20-microliter injection volume. Mean recoveries of 90 and 85% for morphine and morphine-6-glucuronide, respectively, were obtained, the limit of detection being 2 nmol/l (at a signal-to-noise ratio of 3.0).

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.

We have studied the effects of two discrete types of surgical stimulation on contractions in the lower oesophagus. Forty-four female patients undergoing either abdominal hysterectomy or varicose vein surgery were anaesthetized using a standard technique. The frequency of spontaneous oesophageal contractions (SLOC) and amplitude of provoked contractions (PLOC) were greater in those patients undergoing hysterectomy. The oesophageal index (OCI), a single index combining both types of contractions, was found also to relate to the nature of the surgical stimulus.

The most important complications following gastrointestinal surgery are related to disruption of anastomoses. The fate of a gastrointestinal anastomosis is influenced by many factors. Among these, care in the anaesthetic management and postoperative treatment may reduce the incidence of complications. There are two major directions in which such care may be aimed. The prevention of high intra-luminal pressures and excessive longitudinal traction across anastomoses may be aided by care in the administration of neostigmine, and possibly by the avoidance of morphine for provision of intra-operative and postoperative analgesia. Maintenance of, or improvements in, oxygen supply to an anastomosis may be achieved by avoiding hypoxia, hypocapnia and hypovolaemia, and by the use of regional anaesthetic techniques during surgery and/or in the post-operative period. In addition, sedative and analgesic therapy may influence the incidence of postoperative ileus, and may thus contribute to morbidity.

A mobile intensive care unit is an important extension of a regional intensive treatment service. The treatment and monitoring of critically ill patients can be maintained during transfer for specialist investigation or treatment. Such units can be brought into service with low construction and running costs.