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Notes: Ninety four patients undergoing transurethral resection of the prostate underwent Holter electrocardiographic monitoring pre-and postoperatively. There was no difference in silent myocardial ischaemia incidence or load between the spinal (n = 60) ami the general anaesthesia (n = 34) groups. Ischaemic heart disease and a higher Detsky score both significantly increased the incidence of silent myocardial ischaemia but not the ischaemic load of those patients that actually demonstrated ischaemia. In this specific surgical population, not undergoing cardiac or vascular surgery, both ischaemic heart disease and cardiac risk scores are poor predictors of ischaemic load. Merely the presence of short duration silent myocardial ischaemia probably has little predictive value for postoperative adverse outcome.

Notes: The peri-operative and postoperative effects of propofol given by infusion were compared with halothane as a supplement to nitrous oxide-oxygen anaesthesia for body surface surgery in patients who breathed spontaneously. Anaesthesia was induced after opioid premedication, with either propofol 2.5 mg/kg or thiopentone 4–5 mg/kg which were followed respectively by an infusion of propofol 12 mg/kg/hour for 10 minutes and at a variable rate thereafter, or by halothane at a mean inspired concentration of 1.2%. Maintenance of anaesthesia required a median rate of infusion of propofol of 149.4 mg/kg/minute. The cardiovascular effects during induction and maintenance of anaesthesia were similar in the two groups. The overall incidence of side effects was low but immediate recovery was significantly faster in patients who received propofol.

Notes: Noninvasive methods of determining cardiac output (by thoracic electrical bioimpedance) and arterial pressure (by intermittent oscillometry) were used to record minute-by-minute changes in heart rate, mean arterial pressure, stroke volume, cardiac output and systemic vascular resistance following induction of general anaesthesia and laryngoscopy and intubation in 60 healthy female patients who were either unpremedicated, or premedicated with temazepam or papaveretum-hyoscine. Anaesthesia was induced with a sleep dose (3–5 mg.kg−1) of thiopentone and maintained with 70% nitrous oxide in oxygen with 0.5–1% enflurane. Tracheal intubation was facilitated by administration of vecuronium 0.1 mg.kg−1. Mean arterial pressure and cardiac output decreased maximally 5 min after induction in all premedication groups by mean estimates of 21–25% and 14–22% respectively. Heart rate increased initially one minute after induction, but decreased to less than the baseline value 5 min after induction. Systemic vascular resistance was unchanged. The stimulus of laryngoscopy and tracheal intubation was accompanied by a significant pressor response and tachycardia one minute after intubation (with mean increases in mean arterial pressure and heart rate of 29–34% and 22–33% respectively). The increase in mean arterial pressure was secondary to an increase in systemic vascular resistance (36–57%), and was accompanied by a decrease in stroke volume (– 25 to –31%). These changes were significant in all three groups. Cardiac output decreased only in unpremedicated patients. There were wide variations in the different haemodynamic indices. The 5th and 95th centiles for the decreases in mean arterial pressure and cardiac output during induction were –17 to –26, –21 to –33, and –21 to –35mmHg, and –0.7 to –2.0, –0.7 to –2.3, and –0.2 to –1.31.min−1 respectively in unpremedicated patients and those premedicated with papaveretum-hyoscine, or temazepam. Corresponding values for increases in mean arterial pressure and systemic vascular resistance, and decreases in stroke volume following laryngoscopy and intubation, were 16 to 33, 16 to 31.5, and 15 to 31 mmHg; 5.0 to 8.6, 3.5 to 10.2, and 4.3 to 7.8 mmffg.min.−1; and –19 to –31, –11 to –32.5, and –9 to –21 ml respectively.

Notes: Sufentanil in doses of 0.4 and 1.0 μg/kg was used as an analgesic supplement to nitrous oxide-oxygen anaesthesia in 28 patients whose lungs were ventilated during body surface or lower abdominal surgery. Significant decreases in arterial blood pressure followed drug administration (mean 35.6%). Decreases in arterial pressure of greater than 30% occurred in 5 out of 14 patients in the low dose group, and 12 out of 14 in the high dose sufentanil group. There was a blunting of the pressor response to laryngoscopy and intubation after sufentanil. Increases in blood pressure were seen in both treatment groups at the onset of surgery. The peak responses were 27% increase in mean arterial pressure in the low dose group, and 51% increase in the 1.0 μg/kg group. There was however no significant change in heart rate. Fourteen patients (8 in the low dose group) required volatile supplementation during surgery for clinical signs of inadequate anaesthesia. This occurred between 21 and 70 minutes after sufentanil administration, and plasma drug concentrations 0.06 and 0.54 ng/ml. Tracheal extubation was successfully achieved at the end of surgery in 26 out of 28 patients at plasma sufentanil concentrations which ranged from 0.03 to 0.37 ng/ml. The two remaining patients, neither of whom had received additional volatile supplementation, required naloxone to overcome postoperative ventilatory depression. No cases of intra-operative awareness were noted.

Notes: This study investigated the effects of etomidate on endocrine responses to anaesthesia and surgery. Patients undergoing abdominal hysterectomy received standard anaesthetics of either etomidate for induction with etomidate infusion, or thiopentone and halo thane. Etomidate suppressed the secretion of cortisol and aldosterone for between 8 and 22 hours after the end of the etomidate infusion; 11-deoxycortisol secretion was not suppressed during the etomidate infusion, but rose postoperatively; 17α-hydroxyprogesterone suppression also lasted only as long as the etomidate infiion. There were no effects on plasma oestradiol, A CTH, or prolactin, but growth hormone concentrations were elevated in the etomidate group. Etomidate was concluded to have influenced adrenocortical function only, where it probably inhibits 11 β-hydroxylation, 17 α-hydroxylation and other intramitochondrial hydroxylation reactions. There were no clinical sequelae attributable to adrenocortical suppression. The relationship of chemical structure of etomidate and other phenylated imidazoles to inhibition of steroidogenesis is discussed.

Notes: Eighty women (40 for elective Caesarean section and 40 for elective gynaecological surgery) were randomly assigned to one of five treatment groups and received pre-operatively either no medication; magnesium trisilicate mixture (BP) 30 ml; metoclopramide 10 mg intramuscularly; ranitidine 150 mg orally on the night prior to, and the morning of, surgery; or metoclopramide 10 mg intramuscularly in combination with oral ranitidine 150 mg (the latter again given on the night prior, and the morning, of surgery). The effect of these medications on intragastric pH. volume and serum gastrin-17 was measured. No patient receiving ranitidine had a pH of less than 4. Magnesium trisilicate mixture resulted in the largest intragastric pH change although one woman in this group had a pH of 1.7. The largest intragastric volumes were seen in the patients who had received magnesium trisilicate mixture, whilst the patients who had received metoclopramide in combination with ranitidine had the smallest intragastric volumes. Magnesium trisilicate mixture and metoclopramide resulted in no change in serum gastrin levels. However, in the subjects who had received ranitidine on the night prior to surgery, the fasting serum gastrin was significantly higher (p 〈 0.01) than the values in the remaining subjects, the mean (SEM values being 60.3(6.3) pg/ml in those not receiving ranitidine and 111.3(19.5) pg/ml in those who had been given ranitidine.

Notes: Opioid drugs in high doses can obtund the stress response to major surgery but only at the expense of marked cardiorespiratory depression. The postoperative hormonal response to surgical stress was measured in 20 patients undergoing hysterectomy who were given either meptazinol 100 mg or morphine 15 mg intramuscularly at the end of the surgery. Both drugs at the doses used failed to diminish the stress response. Those patients who received meptazinol showed elevated prolactin levels: this may be an indicator of agonist activity at the μ1, opioid receptor.

Notes: Ninety patients, premedicated with temazepam 20 mg, undergoing suction termination of pregnancy, were studied. Forty patients received alfentanil (500 μ g), and thirty halothane (1.5%) as supplements to either etomidate or methohexitone–nitrous oxide–oxygen anaesthesia. A further 20 patients received alfentanil 250 μg at induction of anaesthesia with methohexitone, followed by a further 250 μg immediately prior to the onset of surgery. Recovery was assessed by the time patients took to open eyes on command, to giving their correct date of birth, and to performing the deletion test. Satisfactory operating conditions were not obtained with the combination of etomidate and halothane. Faster recovery was seen in patients with either etomidate or methohexitone and receiving alfentanil (p 〈 0.01) Testing by the ‘p’ deletion test showed impaired psychomotor performance at 30 minutes after cessation of anaesthesia in all groups compared with the pre-operative scores. Side effects leading to unsatisfactory anaesthesia were more frequent in patients who had received etomidate (p 〈0.01).

Notes: An etomidate infusion was used to anaesthetise twelve patients for spinal surgery; six (group I) with 67% nitrous oxide and six (group II) with oxygen enriched air. Anaesthesia was induced with infused etomidate at a rate of 100 μg/kg/minute for 10 minutes and maintained at a rate of 10 μg/kg/minute.Recovery was assessed as the time to opening eyes on command (t1) and the time to giving correct date of birth (t2). In group I, mean value for t1 was 37.9 minutes and t2 59.1 minutes which is significantly longer than in group II where mean value for t1 was 9.0 minutes and t2 15.1 minutes. Blood was taken for estimation of etomidate levels. In group I the maintenance level was 501 ng/ml and the plasma clearance 20.9 ml/kg/minute. In group II the maintenance level was 367 ng/ml and plasma clearance 27.3 ml/kg/minute. Etomidate infusion appears to be a suitable alternative for neuroanaesthesia when nitrous oxide is contra-indicated.

Notes: The intravenous anaesthetic Althesin may be administered by continuous intravenous infusion for maintenance of general anaesthesia, sedation in patients in intensive care units or during investigational procedures. Published reports of experience with this technique are reviewed, with particular attention to the rates of administration employed and the influence of other anaesthetics and analgesic agents used concurrently.