bluuebunny/crossref_metadata_2025_split huggingface dataset:
Midazolam in Paediatric Anaesthesia
Authors: Cole W. H. J. 
Published: January 2019

Midazolam was given intravenously to 100 children over the age of 8 years to induce anaesthesia and a similar control group was anaesthetised with diazepam. The actions of midazolam in children were found to be similar to those of diazepam. Midazolam acted more quickly in children than has been reported in adults. The effects on the circulation and respiration, and the incidence of postoperative amnesia were similar in children to that which has been reported in adults. The incidence of postoperative vomiting after midazolam was 1% in the recovery room and 32% during the first two postoperative days. Laboratory investigations did not demonstrate any adverse effects. Midazolam has a considerable advantage over diazepam being water soluble and injectable safely without dilution. This clinical trial suggests that midazolam is a satisfactory induction agent for children.
Sodium Citrate: An Alternative Antacid for Prophylaxis against Aspiration Pneumonitis
Authors: Wrobel J. , Koh T. C. , Saunders J. M. 
Published: January 2019

In a double-blind study, 107 patients undergoing elective and emergency surgical procedures were given 15 ml of either sodium citrate 0ṁ3 M or placebo 10 minutes before induction of anaesthesia. Gastric contents were sampled immediately after induction and the pH was measured. The mean pH of the gastric contents of patients given sodium citrate was 5ṁ67, whereas for those given the placebo it was 3ṁ21 (p < 0ṁ001). Of patients given sodium citrate 92% had a gastric pH above 3ṁ0 compared with only 37% in the placebo group (p < 0ṁ001). At the end of surgery gastric contents were emptied as completely as possible and the volume and pH measured. There was no significant difference in the mean volume of gastric contents in the two groups. In neither group was the mean pH at the end of surgery significantly different from that after induction.
Detection of Serum IgE Antibodies that React with Alcuronium and Tubocurarine after Lifethreatening Reactions to Muscle-relaxant Drugs
Authors: Baldo B. A. , Fisher M. McD. 
Published: January 2019

Although anaphylactoid reactions to muscle-relaxant drugs are now well recognised, there has been no general agreement on the mechanism(s) underlying the responses. By covalently coupling alcuronium and tubocurarine to a solid phase carrier and using the resultant complexes in radioimmunoassay experiments with patients’ sera and 125I-anti-human IgE, we have found high levels of drug-specific IgE antibodies in the sera of some subjects who reacted to these muscle relaxants. These results provide important supporting evidence that, in some patients at least, lifethreatening anaphylactoid reactions to muscle-relaxant drugs are mediated by drug-specific IgE antibodies.
Cerebral Perfusion and Cerebral Protection during Carotid Endarterectomy
Authors: McMeniman W. J. , Kam P. C. A. 
Published: January 2019

The relative safety of carotid endarterectomy depends upon surgical expertise combined with appropriate monitoring of cerebral perfusion and the ability to intervene either surgically or pharmacologically to match cerebral perfusion to cerebral oxygen requirement. Methods of monitoring adequacy of cerebral perfusion are reviewed and include regional cerebral blood flow measurements, electroencephalographic monitoring, carotid stump pressure measurements, jugular venous oxygen partial pressure, neurological assessment and plethysmographic techniques. When cerebral perfusion is inadequate, such procedures as insertion of a temporary bypass shunt and maintenance of normocarbia may improve cerebral perfusion. Anticoagulants along with pharmacologic intervention to either increase cerebral perfusion pressure or reduce cerebral oxygen requirement may be used to preserve cerebral function.
Anaesthesia and the Kidney
Authors: Cousins Michael J. , Skowronski George , Plummer John L. 
Published: January 2019

Applied anatomy and physiology of the kidney are briefly reviewed. This includes an account of renal blood flow, glomerular filtration rate, juxtaglomerular apparatus, renal autoregulation and intra-renal blood flow distribution, tubular transport mechanisms, solute handling in proximal tubule, function of loop of Henle and distal tubule system. This section concludes with a summary of changes in tubule fluid along the length of the nephron. Acute effects of anaesthesia are reviewed in detail. Indirect effects include those on circulatory and sympathetic nervous systems, autoregulation, endocrine systems such as those involving antidiuretic hormone, adrenaline and noradrenaline, renin-angiotensin and aldosterone. Direct effects of anaesthesia on renal function have now been confirmed both in vitro and in vivo. Delayed direct nephrotoxicity of anaesthetics relates predominantly to methoxyflurane (MOF) and its metabolism to inorganic fluoride. Other factors are MOF dose, genetics, age, enzyme induction, obesity, other nephrotoxic drugs. Clinical implications are presented. Enflurane nephrotoxicity is rare but aetiologic factors are similar to the foregoing. Isoflurane and halothane are not nephrotoxic. A consideration of the influence of anaesthetic management on the incidence and severity of postoperative acute renal failure concludes the review.
Pharmacology of Agents Acting on the Renin-Angiotensin System
Authors: Johnston C. I. , Jackson B. 
Published: January 2019

The renin-angiotensin system is the most important hormonal system in the control of blood pressure. It can be blocked at several steps in its reaction pathway. Angiotensin-converting enzyme, or kininase II, is responsible for catalysing the formation of vasoconstrictor angiotensin II as well as for the breakdown of the vasodilator bradykinin. With the advent of specific orally active angiotensin-converting enzyme inhibitors (captopril and enalapril) a practical and effective means of blocking angiotensin formation is now clinically available. ACE inhibitors are effective long-term therapy in patients with essential hypertension. They are particularly useful in the treatment of severe accelerated drug-resistant hypertension and renovascular hypertension, and the agents of choice for afterload reduction in severe congestive cardiac failure. They have several pharmacological advantages, important in anaesthetic practice, over other hypotensive agents. They have no central nervous or autonomic nervous system effects. Thus, patients being treated with ACE inhibitors retain normal sympathetic cardiovascular responses.
Lorazepam in Open-Heart Surgery — Plasma concentrations before, during and after bypass following different dose regimens
Authors: Boscoe M. J. , Dawling S. , Thompson M. A. , Jones R. M. 
Published: January 2019

Thirty-six patients (29 males and 7 females) undergoing open-heart surgery received one of three different dose regimens of lorazepam. All received a weight-related oral dose (2 mg, 3 mg or 4 mg) pre-operatively for night sedation. Twenty-four patients had an additional weight-related dose (2 mg, 3 mg or 4 mg intravenously) either as part of the induction (12 patients) or just prior to connection of the heart-lung machine (12 patients). Plasma concentrations of lorazepam were measured 20 minutes after induction, immediately before bypass, 30 and 60 on bypass and 30 minutes after bypass. Only when additional intravenous lorazepam was given prior to connection to the heart-lung machine were plasma lorazepam concentrations obtained compatible with complete amnesia.
A Comparative Study of Techniques of Postoperative Analgesia following Caesarean Section and Lower Abdominal Surgery
Authors: Brownridge P. , Frewin D. B. 
Published: January 2019

A double-blind, within-patient trial was carried out to compare intramuscular pethidine 100 mg, epidural pethidine 50 mg and epidural bupivacaine 25 mg for pain relief on the day after caesarean section or lower abdominal gynaecological surgery. Analgesia was assessed on a visual analogue pain scale. Forced expiratory volume in one second (FEV1.0) and venous plasma catecholamine levels were measured immediately before and approximately thirty minutes after each treatment. At the completion of the study the treatments were ranked in order of patient preference. Nineteen patients completed the trial. Analgesia provided by epidural pethidine 50 mg was superior to intramuscular pethidine 100 mg (p <0.05) but not statistically better than epidural bupivacaine. There was no significant difference in the duration of analgesia between the active treatments. A mean increase in FEV1.0 of 18% occurred after both of the epidural treatments, but this did not achieve statistical significance. There was no significant change in catecholamine levels after any of the treatments. Epidural pethidine was preferred by patients over and above intramuscular pethidine and epidural bupivacaine (p <0.05).
Factors Affecting Outcome after Chest Injury
Authors: Moore Peter G. , James Owen F. , Byth Philip L. , Simpson Ian J. 
Published: January 2019

From 1978 to 1983 a total of 328 patients was admitted to Royal Newcastle Hospital Intensive Care Unit with chest injuries; 255 had other injuries as well. Of the 328, 171 developed acute respiratory failure, 174 received mechanical ventilation (159 for acute respiratory failure) and 46 died. The commonest causes of death were head injury (19), sepsis (10) and uncontrollable haemorrhage (10). Associated head (131) and/or abdominal (89) injuries tripled mortality. Those without respiratory, cardiac, renal or hepatic failure (155) had a mortality rate of 5.8% while the remainder had mortality rates of 21.6%, 12.5%, 37.5% and 100%, for respiratory (171), cardiac (8), renal (8) and hepatic (5) failures, respectively. Shock was present on admission in 55, of whom 19 died. Sepsis developed in 59 and 14 with this complication died. Sepsis remains a potentially avoidable late cause of death and attention needs to be directed towards limiting invasive techniques of management to those which are necessary, and towards early diagnosis of abdominal injuries with early exploratory surgery. The best chance of survival in the initial phase of injury may lie in the establishment of an integrated regional trauma centre system together with improved pre-hospital and retrieval systems.
The Position of the Larynx in Children and its Relationship to the Ease of Intubation
Authors: Westhorpe R. N. 
Published: January 2019

Lateral radiographs of the upper airway of children aged from birth to puberty were used to determine the changes in position, with growth, of the tip of the epiglottis, the hyoid, the glottis, and the inferior margin of the cricoid cartilage. There is a marked descent of these structures relative to the cervical spine during the first two years of life. Their position then remains fairly static until puberty, when further descent of laryngeal structures occurs. Using the same methods to determine ease of laryngoscopy with the head and neck in different positions it was shown that in infants the best view is obtained with the atlanto-occipital joint fully extended and the head and shoulders on a flat surface. In adults the best view is obtained with the atlanto-occipital joint fully extended and the head resting on a low pillow. Anatomical explanations for these observations are presented.
Comparison of Propofol and Antagonised Midazolam Anaesthesia for Day-Case Surgery
Authors: Forrest P. , Galletly D. C. 
Published: January 2019

A technique of midazolam/fentanyl/isoflurane/nitrous oxide anaesthesia, in which the benzodiazepine was antagonised by the specific antagonist, flumazenil, was compared with propofol/fentanyl/nitrous oxide anaesthesia for minor outpatient urological surgery. No significant difference was found in the overall ease of anaesthesia; however, using subjective (linear analogue sedation scales) and objective (letter deletion and simple reflex time) tests, recovery was found to be significantly slower for the antagonised midazolam group. For both groups, the most frequent intraoperative problem was patient movement in response to surgical stimulation and, postoperatively, headache. The midazolam group displayed the greatest degree of residual sedation at the 4-hour time of discharge and on arrival home a significantly larger number of patients in the midazolam group slept for a period. It is likely that the dose of flumazenil chosen (1 mg) was inadequate to completely antagonise the dose of midazolam (mean 17 mg) for the full duration of recovery.
Perioperative Hypoxaemia Detected by Intermittent Pulse Oximetry
Authors: Mckenzie A. J. 
Published: January 2019

Perioperative pulse oximetry was performed on one hundred consecutive abdominal surgical patients to audit our management of perioperative oxygenation. Oximetry was performed preoperatively, in the recovery room, and daily in the ward until discharge or the sixth postoperative day, with prescribed oxygen therapy continuing during measurement. Twenty-nine patients had saturations of 90% or less on a total of fifty-one occasions. Twenty-nine patients were prescribed prophylactic oxygen therapy, but seven had oxygen therapy stopped prematurely and were found to have saturations of 90% or less. In this group of patients, clinical assessment of oxygenation and the need for oxygen therapy was inadequate. Intermittent oximetry is rapidly and simply performed, and by detecting patients with arterial haemoglobin desaturation, could improve oxygen prescribing in the perioperative period.
A New Comprehensive Anaesthetic Record
Authors: Jackson C. J. , Scott R. J. 
Published: January 2019

Eternal vigilance and strict attention to detail are the ‘sine qua non’ of safe anaesthesia with the contemporaneous anaesthetic record being the documentation. As an alternative to the manifold and often inadequate forms currently in use, a new rapidly completed anaesthetic record incorporating a comprehensive checklist is presented. Guidelines of the Faculty of Anaesthetists, Royal Australasian College of Surgeons are met. It is argued that the chart improves safety not only by its direction to attention during the preoperative visit and equipment check, but also by its demand for the ongoing attention of the anaesthetist. Reservations are expressed about ‘black box’ recording by trend printout and a perspective for computerised and automated anaesthetic records is also discussed.
Double-Blind Study of the Reversal of Midazolam-Induced Sedation in the Intensive Care Unit with Flumazenil (Ro 15–1788): Effect on Weaning from Ventilation
Authors: Pepperman M. L. 
Published: January 2019

Midazolam (0.1–0.2 mg/kg/hr) and morphine (2 mg/hr) were given by carefully regulated continuous intravenous infusions to thirty patients who required sedation, analgesia and ventilation for between twelve and twenty-four hours in the Intensive Care Unit. The midazolam and morphine infusions were stopped at the end of the period of sedation required and the efficacy of placebo or flumazenil in reversing the sedative effects of midazolam was compared in this double-blind randomised parallel group study. Patients receiving flumazenil were less sedated (P < 0.05), able to obey commands (P < 0.05), weaned from ventilation (P < 0.05) and extubated (P < 0.05) significantly earlier than those receiving placebo.
Thrombocytopenia and Platelet Functional Defects in Pre-Eclampsia: Implications for Regional Anaesthesia
Authors: Schindler M. , Gatt S. , Isert P. , Morgans D. , Cheung A. 
Published: January 2019

A prospective, observational study of forty pre-eclamptic patients was conducted to confirm or refute reports of a platelet functional defect superimposed on the consumptive thrombocytopenia of pre-eclampsia. Investigations included a platelet count, in vivo platelet function as assessed by a Duke bleeding time, and in vitro platelet function as assessed by thromboxane B2 and Platelet Factor 3 (PF 3). The overall incidence of thrombocytopenia was 15%. Prolonged bleeding time and slightly decreased availability of PF 3 (evidence of possible platelet dysfunction) was present in 2.5% of patients while 21% had evidence of fibrinolysis with an elevated monoclonal D-dimer. In the assessment of suitability for regional blockade, a platelet count is essential. If the platelet count is between 50 and 100 × 109/l a bleeding time is indicated.
A Comparative Analysis of the Loss of Amiodarone from Small and Large Volume PVC and Non-PVC Infusion Systems
Authors: Peters P. G. , Hayball P. J. 
Published: January 2019

The time-course of the adsorption of amiodarone hydrochloride onto flexible polyvinyl chloride (PVC) infusion bags and administration sets has been studied under ambient conditions similar to the intensive and coronary care units at the Repatriation General Hospital – Daw Park. When admixtures containing 900–1000 mg amiodarone hydrochloride in 500 ml PVC infusion bags containing glucose 5% were assayed, a minimal (2.7%) loss of amiodarone was detected at 24 hours compared with glass infusion bottles. There was no loss apparent when 100 ml PVC infusion bags were used compared with 100 ml glass bottles. When PVC administration sets were attached to 500 ml glass infusion bottles, maximal adsorption losses of up to 4.9% were observed in the effluent within one hour of the commencement of the simulated infusion. In Australia, the current recommendations by the distributor of amiodarone, Reckitt & Colman Pharmaceuticals, advise that the administration of amiodarone should be via glass infusion bottles or rigid PVC plastic containers without plasticisers together with non-PVC administration lines. These results do not support this recommendation.
Anaesthesia and the Sick Foetus
Authors: Lah F. 
Published: January 2019

The primary cause of foetal illness is placental pathology. The use of diagnostic ultrasound allows for a better understanding of how the foetus may be compromised by inadequate placental function. Anaesthesia affects placental function by changing uteroplacental and umbilical placental perfusion. Regional anaesthesia may have a beneficial effect on these circulations although general anaesthesia may be adapted to produce minimal disturbance of placental circulatory dynamics. The advantages and disadvantages of particular anaesthetic techniques in the delivery of the sick foetus are discussed.
The Melbourne Chart – A Logical Guide to Neonatal Resuscitation
Authors: Roy R. N. , Betheras F. R. 
Published: January 2019

Resuscitation of the asphyxiated infant is one of the great emergencies in medical practice. Properly done, it can save many lives and greatly reduce the morbidity resulting from hypoxic-ischaemic encephalopathy, but if it is ineptly performed, the effects of hypoxic-ischaemic encephalopathy may be accentuated, with resultant increased morbidity and even mortality. Other than paediatricians, few practitioners have regular experience in neonatal resuscitation: indeed many, including obstetricians, anaesthetists, general practitioners and midwives may only rarely face the problem of severe asphyxia. It is therefore essential for the occasional practitioner to have ready reference to a logical guide to resuscitation. We have designed such a guide which is widely distributed in delivery suites and operating theatres in Victoria. Its basic form has been in use for over a decade and it has recently been revised. Use of the chart assists the resuscitator to judge the level of resuscitation required. It is our experience that much unnecessary intervention occurs at resuscitation, and we believe the methods outlined in this schematic chart represent a more conservative but logical approach to neonatal resuscitation. The chart is based on the pathophysiological changes that occur in perinatal asphyxia, directing the user to the appropriate manoeuvres required to correct those changes, depending on the degree of asphyxia which is determined by clinical signs and by use of the Apgar score.
Drug Dependence and Pregnancy: Antenatal and Intrapartum Problems
Authors: Kliman L. 
Published: January 2019

The last decade has seen an increase in the use of illicit drugs and alcohol in the community including an increase in the use of these agents by women in the reproductive age group. With this in mind, health-care workers need to avoid being complacent in caring for these women – they are a high-risk obstetric population with a significant incidence of medical, obstetric and paediatric complications. This paper concentrates on the antenatal and intrapartum problems, and outlines their management. An overview of the problem is presented as well as an illustrative case report.
Neuromuscular Blocking Agents in Paediatric Patients: Influence of Age on the Response
Authors: Meretoja O. A. 
Published: January 2019

This paper reviews the studies in which neuromuscular blocking drugs were comapred in at least two different age groups of patients. Most recent studies have lead to a uniform concept of the variation of the effect of these drugs in different age groups. In general, the dose of a nondepolarizing agent required to produce a particular degree of relaxation is similar in neonates (less than one month), infants (one to twelve months) and adolescents (more than thirteen years). However, in children from three to ten years the dose is significantly greater. The maximal effect is reached more quickly in neonates and infants than in the older children and adolescents. These results can be explained by changes in sensitivity, distribution volume and muscle mass. The duration of effect of a nondepolarizing agent is significantly altered by age only in the case of vecuronium, which has a prolonged action in neonates and infants. Suxamethonium remains as the agent with the most rapid onset.
Suxamethonium – Electromyographic Studies in Children
Authors: Brown T. C. K. , Meretoja O. A. , Bell B. , Clare D. 
Published: January 2019

Suxamethonium was administered to 225 children aged from one to sixteen years, in doses varying from 0.1 to 0.5 mg/kg. Dose responses were determined. ED95 was 445 μg/kg in one to four year olds, 454 μg/kg in the five to ten years group and 270 μg/kg in eleven to fifteen year olds (P < 0.05). There is a wider variability in patient responses to 0.1 and 0.2 mg/kg than to the higher doses. Sixty-two children in the three age groups were given suxamethonium 1 mg/kg. The time from injection to maximum block and to 50% recovery increased with increasing age (P< 0.05).
Rate-Controlled Analgesia: A Laboratory Evaluation of a New Infusion Device
Authors: Currie J. , Owen H. , Ilsley A. H. 
Published: January 2019

We report an evaluation of the Bard Harvard Mini Infuser, one of a new generation of agent-specific intraoperative infusion pumps which are designed for use by the anaesthetist. This pump permits potent intravenous anaesthetic agents to be used in pharmacokinetically designed dosage regimens. The controls are calibrated directly in kg body weight and micrograms per minute rather than the usual settings of ml of solution per hour. The performance was assessed by measuring the volume delivered over given time intervals and all safety functions were tested at least three times. This device was found to be acceptably safe and accurate. Two points to note are that it must be purged every time before it is connected to the intravenous infusion and if an occlusion is suddenly relieved, the patient can receive an ‘accidental bolus’ of up to 1.18 ml of drug. The main advantage of this pump is that it uses undiluted drug direct from the ampoule and does not require any calculations or dilutions prior to use. However, this restricts its use to drugs with a concentration of 500 mcg/ml and in effect means that it is suitable mainly for infusion of alfentanil.