Showing papers in "BJA: British Journal of Anaesthesia in 1978"
294 citations
TL;DR: The complete model is applied to the problem of total renal failure, and shows that patients with this condition are likely to be marginally resistant to small doses of pancuronium, with a normal rate of recovery, however, larger doses arelikely to result in delayed recovery, the duration of effect increasing in a dose-dependent manner.
Abstract: It has been demonstrated that a simple two-compartment kinetic model may account for the changes in plasma concentration of pancuronium after i.v. administration. However, it can be shown that this simple model does not account satisfactorily for the observed changes in muscle twitch response. By the addition of a receptor (biophase) compartment, twitch response can be reconciled with model behaviour and the characteristics resemble those predicted by animal studies. The complete model is applied to the problem of total renal failure, and shows that patients with this condition are likely to be marginally resistant to small doses of pancuronium, with a normal rate of recovery. However, larger doses are likely to result in delayed recovery, the duration of effect increasing in a dose-dependent manner.
194 citations
TL;DR: One thousand patients examined immediately after extubation of the trachea at the end of anaesthesia detected severe lesions of the larynx, and it was not possible to avoid an effect on the voice in nine patients.
Abstract: One thousand patients were examined immediately after extubation of the trachea at the end of anaesthesia. Severe lesions of the larynx were detected in 62 patients (6.2%). The lesions encountered included haematoma, laceration of the mucous membrane, laceration of the muscle and subluxation of the arytenoid cartilage. In spite of early diagnosis and adequate treatment, it was not possible to avoid an effect on the voice in nine patients.
179 citations
TL;DR: A Doppler ultrasound bloodflow detector was used to localize the third division of the subclavian artery, rendering the supraclavicular approach to the brachial plexus safer and highly successful.
Abstract: A Doppler ultrasound bloodflow detector was used to localize the third division of the subclavian artery, rendering the supraclavicular approach to the brachial plexus safer and highly successful.
172 citations
TL;DR: Two-thirds of the "anaesthetic" deaths were attributable to hypovolaemia; respiratory inadequacy following myoneural blockade; complications of tracheal intubation; and inadequate postoperative care and supervision.
Abstract: The mortality associated with 240 483 anaesthetics administered over 10 years at Groote Schuur Hospital, Cape Town, is reported. The frequency of death to which anaesthesia contributed was 0.22 per 1000 anaesthetics (compared with 0.33 per 1000 in the previous 10 years). These deaths were responsible for 2.2% of the total mortality from surgery. Two-thirds of the "anaesthetic" deaths were attributable to (in order of frequency): (a) hypovolaemia; (b) respiratory inadequacy following myoneural blockade; (c) complications of tracheal intubation; (d) inadequate postoperative care and supervision.
150 citations
TL;DR: It was concluded that Etomidate is a potent cerebral metabolic depressant and the cerebrovascular reactivity to carbon dioxide was maintained under etomidate anaesthesia.
Abstract: The effects of etomidate on regional cerebral blood flow (rc.b.f.) and cerebral metabolic rate for oxygen (CMRo2) were studied in seven patients undergoing diagnostic carotid angiography. Following determination of baseline rc.b.f. while awake, the patients were anaesthetized with a single dose of etomidate 15 mg. Thereafter an infusion of etomidate (2 or 3 mg min–1) was administered. Etomidate decreased both rc.b.f.10 (mean decrease 34%) and CMRo2 (mean decrease 45%). It was concluded that etomidate is a potent cerebral metabolic depressant. Furthermore, the cerebrovascular reactivity to carbon dioxide was maintained under etomidate anaesthesia.
124 citations
TL;DR: In this paper, the authors postulate an alternative molecular mechanism, the multi-site expansion hypothesis, for the pressure reversal of continuous i.v. anaesthesia produced in rats by keta-mine, methohexitone, propanidid and thiopentone.
Abstract: We have quantitated the pressure reversal of continuous i.v. anaesthesia produced in rats by keta-mine, methohexitone, propanidid and thiopentone. These and other data are not consistent with the earlier critical volume hypothesis of general anaesthesia and therefore we postulate an alternative molecular mechanism—the multi-site expansion hypothesis.
101 citations
TL;DR: The superficial and deep body temperatures of 23 patients were studied during prolonged anaesthesia for microscopic surgery of the fallopian tubes, and large heat losses occurred on transfer to the recovery room, where the total heat produced increased rapidly and was unrelated to shivering.
Abstract: The superficial and deep body temperatures of 23 patients were studied during prolonged anaesthesia for microscopic surgery of the fallopian tubes. The patients were divided randomly into three groups, receiving either halothane 0.5%, halothane 1% or low-dose fentanyl as a supplement to nitrous oxide, oxygen and myoneural block. Other variables were kept constant, and the theatre temperature was maintained at 24 °C. Temperature changes were unrelated to both the type of anaesthesia and the percentage of subcutaneous fat to body weight. Halothane 1 % decreased the rate of heat loss in the 3rd hour. Large heat losses occurred on transfer to the recovery room, where the total heat produced increased rapidly and was unrelated to shivering.
98 citations
TL;DR: The only side-effect to occur more frequently after administration of the analgesics was drowsiness, the incidence being greater after buprenorphine than after morphine.
Abstract: A double-blind, between-patient comparison has been made of the effects of morphine 10 mg i.v. and buprenorphine 0.3 mg i.v. on the prevention of pain after operation. The drugs were given by the anaesthetist at the end of the operation, and the onset and severity of pain were assessed by a trained nurse. Both drugs caused a significant delay in the appearance of severe pain when compared with the control group, but with buprenorphine the mean delay of 10.5 h was more than twice that of morphine. The only side-effect to occur more frequently after administration of the analgesics was drowsiness, the incidence being greater after buprenorphine than after morphine.
88 citations
TL;DR: Performance following recovery from clinical doses of anaesthetic agents has been discussed recently in an excellent, comprehensive review by Drummond (1975) and this aspect will not be considered here.
Abstract: The professional performance of the anaesthetist is a subject of enormous importance which has been subjected to very little scientific scrutiny. From a questionnaire sent to junior hospital doctors of all specialties, Wilkinson, Tyler and Varey (1975) elicited that more than one-third of medical staff below the grade of registrar believed they suffered an impairment of working efficiency as a result of fatigue. Symptoms which were reported included irritability, inability to speak, tiredness and slowing of thought processes. Junior anaesthetists also believed that breathing anaesthetic waste gases contributed to fatigue and impaired working efficiency. affect performance. Performance following recovery from clinical doses of anaesthetic agents has been discussed recently in an excellent, comprehensive review by Drummond (1975) and this aspect will not be considered here. It is now generally accepted that working in the operating theatre environment is associated with an increase in health hazards. Although the direct cause of this problem has not been established, complaints of headaches by anaesthetists working with unscavenged anaesthetic circuits, data demonstrating illeffects in laboratory animals induced by low concentrations of anaesthetic agents, and laboratory studies
83 citations
TL;DR: The results suggest that there is a risk of prolonged duration of action of pancuronium in patients with cirrhosis, and in these patients, the initial dose to achieve adequate muscle relaxation is high and simultaneously there is slow disappearance of Pancuronium from plasma.
Abstract: The serum and urinary concentrations of pancuronium were measured in 14 surgical patients with cirrhosis and 12 patients free from liver disease undergoing abdominal surgery. A two-compartment open model was used in the pharmacokinetic analysis of the data. A two-fold increase in both the distribution half-life (T½α) from 11 min to 24 min and in the elimination half-life (T½β) from 114 min to 208 min was observed in patients with cirrhosis. In these individuals, the total apparent volume of distribution of pancuronium was increased by 50%. Plasma clearance of pancuronium was decreased by 22%. No significant difference was found in the urinary excretion and biotransformation pattern of pancuronium. These results suggest that there is a risk of prolonged duration of action of pancuronium in patients with cirrhosis. In these patients, the initial dose to achieve adequate muscle relaxation is high and simultaneously there is slow disappearance of pancuronium from plasma. These alterations are mainly a consequence of the increase in the distribution volume of pancuronium in patients with cirrhosis.
TL;DR: Diazepam and flunitrazepam were compared as amnesic and sedative adjuncts to local anaesthesia for diagnostic bronchoscopy in 92 patients and neither of the treatments significantly modified arterial pressure or heart rate.
Abstract: Diazepam and flunitrazepam were compared as amnesic and sedative adjuncts to local anaesthesia for diagnostic bronchoscopy in 92 patients. After local anaesthesia of the pharynx, larynx and trachea with lignocaine, atropine plus diazepam or flunitrazepam was injected i.v. The co-operation of the patients and the technical circumstances under which the bronchoscopy was performed were good in each group. None of the treatments significantly modified arterial pressure or heart rate. Two hours after the injection, flunitrazepam 0.01 mg kg−11 more frequently caused amnesia for pictures shown to the patients during the first 15 min after injection (failure to recall 42–75%, and for bronchoscopy 67%), than did diazepam 0.125 mg kg−11 (failure to recall 21–67%; bronchoscopy 38%). Double doses of the drugs caused amnesic actions similar to those of flunitrazepam 0.01 mg kg−11. When failure to recall was assessed on the following day, 29% and 5% of the patients remembered bronchoscopy after flunitrazepam 0.01 and 0.02 mg kg-1 respectively; after diazepam 0.125 and 0.25 mg kg−11 the corresponding percentages was 59% and 30% (P
TL;DR: Five lambs were anaesthetized, paralysed, mechanically ventilated and connected to a membrane "lung" to permit removal of carbon dioxide to decrease barotrauma, particularly in poorly compliant lungs.
Abstract: Five lambs were anaesthetized, paralysed, mechanically ventilated and connected to a membrane "lung" to permit removal of carbon dioxide. When part of the carbon dioxide was removed in this manner, the tidal volume was decreased to keep PaCO2 constant. For example, when 70% of carbon dioxide was removed by the membrane lung, total ventilation was reduced by 50%, peak inspiratory pressure was decreased by 45%, and PaO2 was kept constant by increasing the inspired oxygen fraction from 0.21 to 0.27%. The removal of carbon dioxide by a membrane during positive pressure breathing could decrease barotrauma, particularly in poorly compliant lungs. Technically, the extracorporeal removal of carbon dioxide is relatively simple procedure.
TL;DR: The effect on intervillous blood flow of lumbar extradural analgesia for Caesarean section was studied in nine healthy women using xenon-133 and the most notable decrease occurred in two patients with simulateous arterial hypotension.
Abstract: The effect on intervillous blood flow of lumbar extradural analgesia for Caesarean section was studied in nine healthy women using xenon-133. Extradural anaesthesia was performed with lignocaine 1½% 16–20 ml with adrenaline 6μg ml−1. Impairment of placental blood flow during the block was observed in seven patients, but the mean decrease (13% from the control value) was not statistically significant. The most notable decrease in intervillous blood flow occurred in two patients with simultaneous arterial hypotension.
TL;DR: There is no increased risk of regurgitation during fasciculations induced by suxamethonium, and the gradients during the study were similar to those in healthy patients.
Abstract: The pressures in the lower oesophageal sphincter (high pressure zone or HPZ) and stomach were measured in 15 patients with duodenal ulcer and 14 patients with no gastrointestinal disease. All the patients were premedicated with morphine 10 mg i.m. In the patients without duodenal dulcer, the pressure gradient between HPZ and stomach was 6.6 ± 0.62 mm Hg (mean ± SEM) before diminishing to 4·9 ±0·86 after induction of anaesthesia with thiopentone. During fasciculations following i.v. suxamethonium, the gradient increased to 7·1± 1·0 mm Hg. In patients with duodenal ulcer, although the absolute pressures were less, the gradients during the study were similar to those in healthy patients. We conclude that there is no increased risk of regurgitation during fasciculations induced by suxamethonium.
TL;DR: A new method of sample preparation for the instrument, based upon immediate haemolysis and fluoridation of blood, has been developed, allowing measurement of whole blood lactate concentration to be performed on samples as small as 150 microlitre within 5 min of withdrawal.
Abstract: A new instrument for the measurement of lactate in biological fluids, the Lactate Analyzer 640, has been evaluated. The method of use recommended by the manufacturer for blood samples was found to be inadequate. A new method of sample preparation for the instrument, based upon immediate haemolysis and fluoridation of blood, has been developed, allowing measurement of whole blood lactate concentration to be performed on samples as small as 150 μlitre within 5 min of withdrawal. The instrument is designed to be operated by a medical practitioner. Excellent correlation with a conventional enzymatic assay was found. These features make this new method particularly applicable to rapidly changing clinical situations such as shock in adult patients, asphyxia neonatorum and intrapartum foetal hypoxia.
TL;DR: The effects of 4-aminopyridine (a non-anticholinesterase antagonist of curare-like agents) on the evoked muscle action potentials (EMAP) in a patient with Eaton Lambert Syndrome are reported.
Abstract: SUMMARY The effects of 4-aminopyridine (a non-anticholinesterase antagonist of curare-like agents) on the evoked muscle action potentials (EMAP) in a patient with Eaton Lambert Syndrome are reported. On two separate occasions the i.v. administration of 0.31 mg kg -1 and 0.62 mg kg -1 was followed by a 300% increase of EMAP for about 2 h without serious side-effects.
TL;DR: It is concluded that care should be exercised if amikacin is administered during surgery in conjunction with tubocurarine, as the neuromuscular effects of amkacin in vivo were augmented greatly after pretreatment with tubOCurarine.
Abstract: The effects of the new aminoglycoside antibiotic amikacin on neurohumoral transmission were tested in the anaesthetized cat, and in mouse, rat and chick isolated nerve-muscle preparations. Amikacin had blocking actions on both autonomic and neuromuscular transmission. The autonomic effects were caused mainly by ganglion blockade and were reversed by calcium. The amikacin-induced neuromuscular blockade resulted from a decreased release of acetylcholine and a reduced postjunctional sensitivity. Intracellular recording from end-plates in the rat diaphragm demonstrated that amikacin had magnesium-like effects on acetylcholine release. The blockade was reversed completely by calcium, 4-aminopyridine and 3, 4-diaminopyridine and partially by neostigmine. The neuromuscular effects of amikacin in vivo were augmented greatly after pretreatment with tubocurarine. It is concluded that care should be exercised if amikacin is administered during surgery in conjunction with tubocurarine.
TL;DR: Using the rate of absorption of paracetamol following oral administration of the drug, gastric emptying was measured in 21 patients following hysterectomy and inhibited markedly in patients receiving narcotic analgesia after operation, but only a moderate delay was observed in patients undergoing extradural analgesia.
Abstract: Using the rate of absorption of paracetamol following oral administration of the drug, gastric emptying was measured in 21 patients following hysterectomy. Gastric emptying was inhibited markedly in patients receiving narcotic analgesia after operation, but only a moderate delay was observed in patients undergoing extradural analgesia.
TL;DR: There is much indirect and circumstantial evidence, reviewed here, which, in the opinion of most observers, justifies fully both concern about contamination of theatre air and measures to reduce it.
Abstract: Although it is a fact that the operating theatre environment is contaminated by anaesthetic gases which are taken up by the body tissues of theatre personnel, and although for the past 10 years and more there have been investigations of the consequences for health, there is still no direct evidence that this contamination is a health hazard. However, there is much indirect and circumstantial evidence, reviewed here, which, in the opinion of most observers, justifies fully both concern about contamination of theatre air and measures to reduce it.
TL;DR: Following oral administration the effects on the eye are minimal even after the highest doses of the two drugs, while the decrease in salivation is adequate, and the ratio of oral to i.m. doses of atropine appears to be 2:1 and that of hyoscine about 5-6:1.
Abstract: The effects of equivalent doses of atropine and hyoscine following oral and i.m. administration were assessed on salivary secretion, heart rate, arterial pressure, body temperature, pupillary size, near-point of vision and swear-gland activity. The ratio of oral to i.m. doses of atropine on heart rate and salivary secretion appears to be 2 : 1 and that of hyoscine on salivary secretion about 5–6: 1. Following oral administration the effects on the eye are minimal even after the highest doses of the two drugs, while the decrease in salivation is adequate.
TL;DR: The metabolic effect of infusing 1.0-1.5 litre of Hartmann's solution to normal subjects and those with maturity onset diabetes has been studied during surgery and it is suggested that Hartmann’s solution may be metabolically disadvantageous in diabetic patients.
Abstract: The metabolic effect of infusing 1.0–1.5 litre of Hartmann's solution to normal subjects and those with maturity onset diabetes has been studied during surgery. It was found that the use of Hartmann's solution after operation was associated with a 7.5 mmol litre'1 increase in plasma glucose concentration compared with an increase of 2.1 mmol litre−1 in diabetic patients who received no i.v. fluids. In non-diabetic subjects who received Hartmann's solution the increase was 2.5 mmol litre−1. It is suggested that Hartmann's solution may be metabolically disadvantageous in diabetic patients.
TL;DR: In 14 patients undergoing open-heart operations the haemodynamic effects of diazepam 0.4 mgkg(-1) followed by ketamine 2 mg kg−1 were studied, and no signfiicant change in heart rate occurred in any patient at any time during the period of study.
Abstract: SUMMARY In 14 patients undergoing open-heart operations the haemodynamic effects of diazepam 0.4 mg kg-1 followed by ketamine 2 mg kg-1 were studied. In eight patients undergoing coronary bypass surgery, the mean arterial pressure decreased significantly after diazepam from 90.3±7.4 (SEM) to 78.0±5.0 mm Hg (P
TL;DR: Segmental extradural analgesia with a small dose (20 mg) of bupivacaine did not change placental blood flow significantly and the addition of adrenaline 20 microgram produced no effect.
Abstract: Placental blood flow was measured during the first stage of normal labour using a xenon-133 clearance technique before and after segmental extradural analgesia. Analgesia was produced with 0.5% plain bupivacaine in eight patients and with 0.5% bupivacaine-adrenaline in 10 patients. Segmental extradural analgesia with a small dose (20 mg) of bupivacaine did not change placental blood flow significantly. The addition of adrenaline 20 μg produced no effect.
TL;DR: The activity of δ-aminolaevulinic acid synthase (E.C.37) (the rate-limiting enzyme for haem and porphyrin biosynthesis) has been measured in the rat liver after the repeated administration of anaesthetic agents in vivo.
Abstract: The activity of δ-aminolaevulinic acid synthase (E.C. 2.3.1.37) (the rate-limiting enzyme for haem and porphyrin biosynthesis) has been measured in the rat liver after the repeated administration of anaesthetic agents in vivo. The activity of the enzyme was increased by Althesin, chlordiazepoxide, enflurane, etomidate, lignocaine, methohexitone, methoyflurane, pentazocine and thiopentone and decreased by procaine. No significant changes in activity occurred after the administration of amethocaine, atropine, bupivacaine, diazepam, droperidol, halothane, ketamine, morphine, nitrous oxide, pethidine, phenoperidine, prilocaine and propanidid. It is suggested that those anaesthetic agents which induced activity of the enzyme should not be administered to patients with an acute porphyria.
TL;DR: A new, simple and safe technique for blind oesophageal intubation is outlined and two cases of accidental invasion of the trachea by oesphageal tubes are described.
Abstract: SUMMARY Accidental invasion of the trachea past an inflated cuff may occur more easily when endotracheal tubes with soft, low pressure cuffs are used. A new, simple and safe technique for blind oesophageal intubation is outlined. Two cases of accidental invasion of the trachea by oesophageal tubes are described.
TL;DR: The relationship between the plasma concentration of morphine and morphine-induced changes in ventilation and the ventilatory response to carbon dioxide was studied in 17 healthy adults undergoing elective surgery under general anaesthesia.
Abstract: The relationship between the plasma concentration of morphine and morphine-induced changes in ventilation and the ventilatory response to carbon dioxide was studied in 17 healthy adults undergoing elective surgery under general anaesthesia. Each subject was given morphine sulphate 0.15 mg kg−1 i.m.; ventilation (VE), end-tidal Pco2(PE′CO2), mixed venous PVCO2(PVCO2) and ventilatory response to carbon dioxide (δVE/δPCO2) were measured before and within 90 min after injection. Mixed venous PCO2 and δVE/δPCO2 were measured by standard rebreathing methods; plasma morphine concentration was measured by radioimmunoassay. Maximum plasma morphine ranged from 30 to 120 ng ml−1, between 4 and 60 min after injection. There was a significant increase in mixed venous PE′CO2 (P
TL;DR: In a randomized, prospective study of patients undergoing large bowel anastomosis, 47 patients received subarachnoid block and light general anaesthetic, and 51 received conventional general anaesthesia with intermittent positive pressure ventilation.
Abstract: In a retrospective study, 68 large bowel anastomoses carried out on patients under subarachnoid or extradural spinal nerve block with light general anaesthesia were compared with 26 anastomoses on patients receiving general anaesthesia alone. Dehiscence occurred in 7.4% of anastomoses performed under spinal nerve block compared with 23.1 % in the control group. In patients receiving morphine, anastomotic dehiscence occurred after 15.2% of operations, compared with 5.9% in patients receiving pethidine. These differences are not statistically significant. However, the findings indicate the need for larger prospective studies.