bluuebunny/crossref_metadata_2025 huggingface dataset:
Tutor-Student Interaction in the Operating Theatre
Authors: Paget Neil S. , Lambert Thomas F.
Published: January 2019

This paper examines the view that productive teaching in the operating theatre requires a recognition of the unique set of factors which may influence the process of communication. For tutor-student interaction to occur in a productive manner, the tutor's behaviour will need to be modified to suit the demands of the other tasks in which both tutor and student are involved. The particular value of recognizing the role of nonverbal behaviours during interaction is discussed, with the use of specific examples related to the positioning of the tutor and student, and their use of facial expression, the eyes and voice.
Teaching and Learning in the Operating Theatre
Authors: Lambert T. F. , Paget N. S.
Published: January 2019

The anaesthetist's role during an anaesthetic is one of vigilance. Any interaction between tutor and student in this situation must be structured around the vigilance task. Teaching that recognizes this role may be educationally fruitful and may even improve vigilance. Teaching which disregards this function is less likely to result in learning and may interfere with patient care. Some of the types of teaching that are likely to be appropriate or inappropriate to different phases of an anaesthetic are indicated.
The use of Summary Answers as the Basis for Tutorials
Authors: Brown T. C. K.
Published: January 2019

The use of summary answers to a question as an aid to introducing and guiding a tutorial is described using as an example a question about the physiological changes associated with pyrexia. It illustrates a method that involves all the students and develops a logical comprehensive answer that can also be helpful to students preparing for examinations.
The Value of Anaesthesia Training in the First Two Postgraduate Years
Authors: Roberts M. T. S. , Baker A. B.
Published: January 2019

The value of an anaesthetic attachment during the first two postgraduate years is considered under three major headings, the value to the recent graduate, the value to the specialty, and the value to the community.

The anaesthetic attachment offers all recent graduates an opportunity to perfect practical skills which should from part of the armamentarium of all doctors, and for some there is the option to aquire the ability to administer a safe anaesthetic. Exposure to the specialty at this time is important for recruitment to the specialist ranks.
Acute Appendicitis and Continuous Peritoneal Lavage
Authors: Gjessing Jon , Tomlin P. J.
Published: January 2019

In a series of 117 patients of all ages who were found to have acute appendicitis with perforation, it was found that continuous peritoneal lavage started immediately after appendicectomy had a significant effect in reducing the morbidity and complication rate of this condition. The treatment lasted on average 18 hours and approximately 40 litres of dialysate were used per patient. Treatment was continued until the effluent was macroscopically clean.
An Index of Cardiac Output Derived from the Cardiopneumogram
Authors: Brown M. J.
Published: January 2019

The cardiopneumogram has been reinvestigated as an index of stroke volume and cardiac output in anaesthetized dogs. Using a water-filled oesophageal balloon to calibrate the system good correlations have been found between the values derived from dye dilution and the indices obtained from the cardiopneumogram.
An Evaluation of Preoperative Methods of Preventing Postoperative Pulmonary Complications
Authors: Wheatley I. C. , Hardy K. J. , Barter C. E.
Published: January 2019

The effectiveness of three current regimes of preoperative respiratory care in reducing postoperative respiratory complications following herniorrhaphy was studied prospectively. No smoking for five days plus intensive physiotherapy, five days no smoking, and routine hospital admission two days preoperatively were the regimes. Clinical, bacteriological, chest X-ray, blood gas and respiratory function test data were the criteria for assessment. The same surgical and anaesthetic team performed each operation. No statistical difference between the groups for pulmonary complications was noted. A significant correlation was found between the preoperative vital capacity and arterial pO2; also between the preoperative forced expiratory volume in one second-vital capacity ratio with the postoperative arterial pO2.
Frusemide and Lithium Toxicity
Authors: Oh T. E.
Published: January 2019

Lithium toxicity following frusemide administration is reported.

The clinical features, possible causative mechanisms, and management of the intoxication are discussed.
An Alternative Block for Post Circumcision Analgesia
Authors: Bacon Andrew K.
Published: January 2019

A simple, effective nerve block for post circumcision analgesia is described and evaluated in a series of patients.
Ketamine and Paediatric Radiotherapy
Authors: Edge W. G. , Morgan M.
Published: January 2019

Two hundred and seventy-two ketamine anaesthetics have been given to sixteen children undergoing radiotherapy. Satisfactory conditions were provided in every case and the incidence of complications was low. At the present time ketamine would appear to be the most satisfactory agent in those children who require sedation in order to undergo radiotherapy.
Postoperative Arterial Hypoxaemia
Authors: Morton A. , Mahoney P. , Hansen P. , Holling J. , Lindley T.
Published: January 2019

Postoperative arterial oxygen tension was measured in a group of patients. Unacceptably low levels were found in 32% of the patients and this hypoxaemia persisted in some cases for three days. The results enforce the principle that some patients should be given prolonged oxygen therapy and this should cease only when blood gas analysis demonstrate the patients ability to maintain a safe PaO2 breathing air.
Epidural Block for Abdominal Surgery: Aspects of Clinical Pharmacology of Etidocaine
Authors: Cousins M. J. , Augustus J. A. , Gleason M. , Morgan D. J. , Thomas J.
Published: January 2019

A randomized, prospective, controlled study has compared 1% etidocaine (E) in nineteen patients and 0.5% bupivacaine (B) in 22 patients when used with 1/200,000 adrenaline for epidural blockade. There were unexpected similarities in onset profiles for the two agents, however etidocaine produced a superior intensity of sensory and motor blockade without increased toxicity.

Onset times for sympathetic blockade (E = 6.9 ± 1.2, B = 6.8 ±1.2 minutes) were similar for both agents as were times to maximum change in blood pressure (E = 19.4 ± 9.7, B = 18.9 ± 3.7 minutes).

Initial onset time for sensory loss to pin prick (partial sensory block) was surprisingly similar for the two drugs (E = 5.6 ± 0.6, B = 6.4 ± 0.7 minutes). However, onset of loss of touch sensation (complete sensory block) was much more rapid for etidocaine (E = 17.7 ± 1.7 minutes, B = 36.8 ± 3.5 minutes). Readiness for surgery, as assessed by spread of complete sensory block into four segments above and below the injection site, was rapid for etidocaine (23.1 ± 2.3 minutes) but this degree of blockade was only achieved in two patients following bupivacaine. Complete blockade on both sides of the body was achieved for two segments on either side of the infection site in 100% of patients following etidocaine, compared to only 30–50% following bupivacaine. A similar example of superior neural penetration was seen in onset of blockade of the large S1 root (E = 8.3 ± 1.4, B = 16.2 ± 4.6 minutes)

Complete spread of motor blockade was much more rapid for etidocaine (14.7 ± 2.8, B = 28.9 ± 2.8 minutes). Degree of motor blockade was also significantly greater for etidocaine from ten minutes post blockade onwards (P < 0.001).

Peak plasma concentrations were in keeping with ctox/cmax ratios of 1.9 for bupivacaine and 2.7 for etidocaine. Etidocaine was shown to be extensively and rapidly metabolized and to have a high degree of plasma protein binding.
The Effect of Speed of Injection on the Potency of Anaesthetic Induction Agents
Authors: Aveling W. , Bradshaw A. D. , Crankshaw D. P.
Published: January 2019

The effect of speed of injection on the hypnotic actions of thiopentone, methohexitone, propanidid and Alfathesin was studied in elective surgical patients. The sequential up-and-down technique was used to determine ED50 values. A significant reduction in ED50 was observed for doses injected over five seconds when compared with doses injected over fifteen seconds for thiopentone (64%, P=.001) and methohexitone (83%, P=.05). In the case of Alfathesin, relatively wide confidence limits were observed at all injection speeds and reduction in ED50 at fifteen seconds (63%, P=.01) was noted when compared with the ED50 at five seconds. No significant differences were noted with any of the drugs studied, for variations in infusion time between fifteen, thirty and sixty seconds.

It was concluded that only at very rapid infusion rates does the speed of injection influence the potency of the commonly used induction agents.
The Elimination of Pollution by a Non Inhalational Technique
Authors: Holmes C. McK. , Henderson R. S.
Published: January 2019

A method is described whereby major surgery can be accomplished without inhalational anaesthetic agents, thus completely eliminating operating room pollution.

The method is based on the balanced use of three intravenous agents — morphine, alcuronium and gamma-hydroxybutyrate (GHB). In the dose chosen for GHB, reliable unconsciousness can be produced for surgery of any length, and using physostigmine as an antidote, patients can be wakened within ten minutes.

The advantages are convenience, simplicity of equipment, low cost, absence of pollution and good patient acceptance.

The disadvantages are a certain incidence of hypertension and in this series, a small failure rate with the antidote.
A Case of Rhabdomyolysis Associated with Suxamethonium
Authors: Gibbs J. M.
Published: January 2019

A boy presenting for oesophagoscopy developed myoglobinuria during convalescence from the procedure. A susceptibility to malignant hyperpyerexia was considered in the differential diagnosis but was felt to be unlikely on the basis of in vitro testing of muscle biopsy specimens. A review of relevant papers suggests that rhabdomyolysis of significant degree following suxamethonium administration may be more common than generally appreciated, particularly in children.
The Bird Respirator Modified for PEEP, CPAP and IMV
Authors: Torda T. A. , Roderick C.
Published: January 2019

A Bird Mk. 8 respirator has been modified to permit the use of PEEP, CPAP and IMV. Gas supply is from an oxygen blender to allow easy adjustment of the inhaled oxygen concentration. A special fitting was made to mount a flow meter which supplies the IMV reservoir. PEEP is generated by the Mk. 8 negative pressure generator mounted in opposition to exhalation and its magnitude can be adjusted by the negative pressure control of the respirator. This modified machine is simple, reliable and relatively inexpensive.
No Ignition Risk with Hyperbaric Enflurane
Authors: Baker A. B. , Unsworth I. P.
Published: January 2019

A series of experiments was undertaken with Enflurane under hyperbaric conditions to determine whether or not it was explosive under these conditions. No risk of detonation was shown with concentrations of Enflurane up to 5% in either oxygen or nitrous oxide mixtures under conditions of hyperbaria to 3 A.T.A. (Atmospheres Absolute).
A New Intubating Forceps
Authors: Liberman Henry
Published: January 2019

A new intubating forceps is described. The forceps grip the endotracheal tube from the front and back instead of from the side as do Magill's forceps. The advantages of the forceps are a more secure grasp; improved field of vision; better manipulating ability and reduced likelihood of trauma to tissues or tube cuff.
Chlormethiazole (Hemineurin) Infusion as Supplemental Sedation during Epidural Block
Authors: Schweitzer S. A.
Published: January 2019

Chlormethiazole was used as sedation in a series of patients having surgery under epidural anaesthesia. Results are reported and discussed.
Enflurane Nephrotoxicity and Pre-Existing Renal Dysfunction
Authors: Cousins Michael J. , Fulton Ann , Haynes W. David G. , Whitehead Richard
Published: January 2019

This study provides the first morphological evidence of significant structural damage following high doses of enflurane alone and confirms previous findings of transient renal functional abnormalities following high dosage enflurane.

The study also indicates that enflurane may have a greater potential for renal toxicity in the presence of renal impairment. Treatment of Fischer 344 rats with a nephrotoxic dose of gentamicin prior to six hours of enflurane (GE) anaesthesia at 1 MAC resulted in increased serum concentration of the enflurane metabolite inorganic fluoride (GE, 43.9 ± 1.5; E, 34.5 ± 1.8 μ mol/L), increased urine flow rate and a greater degree of structural damage in renal proximal convoluted tubule cells than was observed with either gentamicin (G) or enflurane (E) alone. Treatment with gentamicin prior to enflurane also resulted in reduced urinary osmolality compared to enflurane or gentamicin alone (GE, 742 ± 57; E, 1709 ± 66; G, 985 ± 32 m0sm/kg).
Local Cerebral Blood Flow and the Electrocorticogram during Sodium Nitroprusside Hypotension
Authors: Miller C. L. , Lampard D. G. , Griffiths R. I. , Brown W. A.
Published: January 2019

Changes in local cerebral blood flow during sodium nitroprusside hypotension were measured using the hydrogen electrode technique.

At mean arterial pressures from 90% to 50% of control values, local cerebral blood flow showed a significant decrease by 20%. When blood pressure was reduced below 50%, the local cerebral blood flow increased significantly and approached control levels. It is suggested that the flow increase may be due to local hypoxia. Associated with this increase were electrocorticogram changes indicative of hypoxia.

The significant decrease in mean local cerebral blood flow and the large range of flows seen during mild hypotension indicate that autoregulation is impaired. During hypotension, intracranial pressure increased by, at most, 3 mm Hg.

Cardiac output was usually unaffected and was never decreased by more than 20%.
Studies in Man with a Constant-Rate Infusion of Tubocurarine
Authors: Shanks C. A. , Ramzan M. I. , Triggs E. J.
Published: January 2019

Tubocurarine (dTC) was administered to twenty patients by intravenous infusion at a predetermined constant rate, and the twitch responses recorded at stimulus intervals of 10 seconds (0.1 Hz). In half the group dTC plasma concentrations were measured both during and following the infusion. This provided data for derivation of the pharmacokinetic parameters, two plasma concentration-response curves and the dose-response curve. The mean effective dTC plasma concentration for 50% paralysis during the infusion (onset) was 0.93 fig/ml, but was lower post-infusion (offset) (0.54 μg/ml, p < 0.001). The steady state dTC plasma concentration which should produce 95% paralysis was predicted to lie between 0.95 and 1.67 μg/ml. In the range 20 to 80% paralysis the slopes of the two (log) concentration-response lines were similar, although steeper than the associated (log) dose-response regression line, the test for parallelism showed no statistical difference. Combination of the plasma concentration-response curve with pharmacokinetic models was used to predict the time course of paralysis in patients with normal and impaired renal function.

Dose-response curves for the other 10 patients were also constructed to stimulus frequencies from 0.02 to 5 Hz. In the range 20 to 80% paralysis the regression lines appeared to be parallel. The results were pooled for all patients at a stimulation rate of 0.1 Hz, giving a mean effective dose of dTC at 95% paralysis of 0.53 mg/kg, and an ED50 of 0.22 mg/kg.
Cardiovascular and Subjective Central Nervous System Effects of Long-Acting Local Anaesthetics in Man
Authors: Mather Laurence E. , Tucker Geoffrey T. , Murphy T. M. , Stanton-Hicks M. d'A. , Bonica J. J.
Published: January 2019

Intravenous infusions of etidocaine 50, 75 and 100 mg and bupivacaine 75 mg were carried out over ten minutes in healthy young adult males. Cardiovascular sequelae were generally trivial at all doses. A collection of subjective central nervous system symptoms were described which may be regarded as early warning of impending local anaesthetic toxicity. Plasma concentrations of etidocaine were proportional to dose and ranged from 2 μg/ml to 5 μg/ml at the termination of the infusion. Plasma concentrations of bupivacaine were similar to those from the same dose of etidocaine but declined more slowly on cessation of infusion.
The Combination of General Anaesthesia and Epidural Block I: The Effects of Sequence of Induction on Haemodynamic Variables and Blood Gas Measurements in Healthy Patients
Authors: Germann P. A. S. , Roberts J. G. , Prys-Roberts C.
Published: January 2019

The haemodynamic effects of epidural block, administered before or after general anaesthesia, were investigated in twelve healthy women scheduled for elective gynaecological surgery. The effects of 10° head down tilt and administration of atropine 0.6 mg intravenously were also determined. Haemodynamic measurements included systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressure, heart rate (HR), cardiac output (CO) and systemic vascular resistance (SVR). In those receiving general anaesthesia first (Group A) (thiopentone/suxamethonium/N2O/O2) significant changes occurred only at the time when epidural block and general anaesthesia were both present: SAP, DAP and MAP (-22%, p < 0.001) were reduced compared to awake control values, however changes in HR, CO and SVR were not significant. In those receiving epidural block first (Group B) (1.5% lignocaine, mean dose 270 mg), MAP was reduced by 20% (p < 0.01) from awake control values after epidural block and there was a further reduction to 35% below control (p < 0.001) when general anaesthesia was induced. These changes were accompanied by a significant reduction in SVR.

Comparison of all variables between Group A and Group B showed no clinically significant differences, indicating that the order of performance of epidural block (before or after general anaesthesia) did not affect haemodynamic variables. Head down tilt resulted in no haemodynamic changes in the presence of general anaesthesia or epidural block alone and only minimal changes when the two were combined. In contrast, intravenous atropine (0.6 mg) resulted in a return of arterial pressures to essentially baseline values in both Group A and Group B (HR increased 84%, p < 0.001; MAP increased 37%, p < 0.001; CO increased 70%, p < 0.001).
Intensive Care Data — I: Computer Controlled Analysis
Authors: Austin K. L. , Phillips G. D.
Published: January 2019

A flexible, simple computer-controlled system for analysis of administrative and clinical data in intensive care is described. The system uses an interactive data input programme to facilitate data entry, an editor to correct errors, and the Statistical Package for the Social Sciences (SPSS) for data selection, retrieval and analysis.

The system has the following features: data input is simple; large amounts of data can be handled rapidly and accurately; old data is readily available for comparison with new data and can be included in the present analysis; available statistical packages remove the need for a programmer; complex analyses are possible. The system has been successfully used for two years to provide administrative and clinical data which is pertinent to patient care.
The Incidence and Aetiology of Phrenic Nerve Blockade Associated with Supraclavicular Brachial Plexus Block
Authors: Knoblanche G. E.
Published: January 2019

A trial to ascertain the true incidence of inadvertent phrenic nerve block with brachial plexus block via the supraclavicular approach was carried out. Phrenic nerve block was monitored by x-ray screening of the diaphragm. There was an incidence of phrenic nerve block of 67% (10 cases of diaphragmatic paralysis in 15 brachial blocks).

The possible causes of phrenic nerve block with brachial block are discussed. It is concluded that the phrenic nerve is blocked peripherally in front of the scalenus anterior.
Assessment of Sympathectomy — the Skin Potential Response
Authors: Cronin K. D. , Kirsner R. L. G.
Published: January 2019

Objective assessment of the results of surgical sympathectomy and sympathetic block (both temporary and permanent) are not widely practised. This article comments briefly on the available methods, and describes the use of the abolition of the skin potential response (formerly known as the psychogalvanic reflex) to assess the abolition of sympathetic function. This method of assessment has proved useful in clinical practice.
Banked Autologous Blood for Caesarian Section
Authors: Davis Richard
Published: January 2019

Experience with the use of banked autologous blood in five patients undergoing elective caesarian section showed that two patients developed painless uterine contractions during phlebotomy, and a third delivered an infant who developed severe respiratory distress. The other two patients had no complications and delivered healthy infants. Caution is needed before recommending the use of this technique in obstetric practice.
Epidural Analgesia with Morphine a Preliminary Communication
Authors: Torda T. A.
Published: January 2019

Morphine sulphate 2 to 4 mg was given by epidural injection for analgesia in eleven patients whose pain was ischaemic, traumatic or post-operative. Excellent analgesia was obtained in ten of the eleven patients without significant side effects. This technique appears to offer relief in post-operative and other types of severe pain and has been continued for up to five days.
Suxamethonium Fasciculations: A Topographical Study
Authors: Collier Clive B.
Published: January 2019

It has been found in a group of 455 gynaecological patients that not all the voluntary muscles of the body respond to suxamethonium in the same way. One group of muscles (e.g. biceps) which is sensitive to suxamethonium, responds by fasciculating in almost every individual. A second, resistant, group of muscles (e.g. pectoralis major) is almost totally unresponsive to suxamethonium. A third muscle group (e.g. triceps) shows fasciculations in about 60% of cases and appears intimately associated with the development of suxamethonium pains, for if fasciculations do occur then suxamethonium pains are likely to ensue, but not necessarily involving all the fasciculating muscles. A theory to account for these different groups has been proposed involving the known variation in distribution of red and white muscle fibres throughout the body.
Neurogenic Pulmonary Oedema in Man: Aetiology and Management with Vasodilators based on Haemodynamic Studies
Authors: Loughnan P. M. , Brown T. C. K. , Edis B. , Klug G. L.
Published: January 2019

Acute pulmonary oedema is a rare complication of head injury. A case is reported in which the pulmonary oedema was treated initially by tracheal intubation, constant positive airway pressure, ventilation and isoprenaline. Subsequent treatment was by vasodilatation with sodium nitroprusside and phenoxybenzamine and the patient made a good recovery.

The findings are discussed in relation to reported experimental work. The aetiology appears to be related to a massive sympathetic discharge leading to systemic vasoconstriction, shift of blood to the pulmonary circulation with left ventricular failure and pulmonary oedema.
Needle Tracheostomy: A Laboratory Study
Authors: Dobbinson T. L. , Whalen J. , Pelton D. A. , Nisbet H. I. A. , Volgyesi G.
Published: January 2019

Percutaneous needle tracheostomy and transtracheal ventilation continues to be advocated for the management of upper airway obstruction. Recent studies recommend the use of artificial ventilation. However, as apparatus for this is not always available and because there remains some doubt regarding conditions for successful use of needle tracheostomy during spontaneous respiration, we undertook such a study in dogs.

Pressure-flow characteristics of short hollow needles 18–10 SWG were first determined. The smallest of these (14 SWG Bardic Intracath) that would deliver flow sufficient (by calculation) to meet the respiratory requirement of 10–13 kg laboratory dogs was selected for further study.

Respiration was possible by spontaneous or artificial methods in the presence of complete tracheal occlusion. Little or no deterioration was noted in an hour of such breathing. Artificial ventilation by machine and by hand could considerably lower PaCO2.

We conclude that the technique is possible provided appropriate needles are selected and care is given to their method of use.
Subclavian Vein Catheterisation for Cardiac Surgery in Children
Authors: Poole John L.
Published: January 2019

Infraclavicular subclavian vein catheterisation is a useful means of measuring central venous pressure and establishing a central infusion line in children undergoing open heart surgery. In 48 children ranging in age from 15 months to 13 years, there was a high success rate and no morbidity.
Clinical Experience with Epidural Morphine
Authors: Torda T. A. , Pybus D. A.
Published: January 2019

Epidural analgesia with morphine sulphate was administered to 130 patients. Of 96 patients with postoperative pain, 74 experienced good analgesia, 14 obtained a fair degree of pain relief, and in eight the method was unsatisfactory. Of the 34 non-operated patients 30 had good pain relief and the method failed in one. The most common cause of failure of analgesia was an incorrectly placed epidural catheter. Urinary difficulties and pruritus were encountered as the principal side-effects. One patient suffered depression of the level of consciousness following epidural drug administration and in one, epidural opiate appears to have contributed to hypotension.
The Effect on Heart Rate of Neuromuscular Blockade Reversal by Pyridostigmine
Authors: Long Geoffrey , Marsh H. Michael
Published: January 2019

Pyridostigmine without atropine, pyridostigmine with atropine or neostigmine with atropine were used to antagonise neuro-muscular blockade induced by d-tubocurarine in forty otherwise healthy, female patients recovering from gynaecological surgery. Pulse rates fell significantly (P < 0.01 control heart rate 72 ± 18 beats/min (M ± SD) to 55 ± 13 beats/min) at ten minutes after pyridostigmine (10 mg/70 kg), necessitating administration of atropine (1.25 mg/70 kg) by fifteen minutes after pyridostigmine. After an initial rise in rate, pulse rates also fell significantly (P < 0 01 control heart rate 70 ± 12 beats/min to 44 ± 11 beats/min) at fifteen minutes after injection of neostigmine (2.5 mg/70 kg) with atropine (1.25 mg/70 kg) By contrast when pyrdostigmine and atropine were used together, pulse rates rose and then fell, but mean values never fell below control during a twenty-minute observation period. It was concluded that pyridostigmine should not be given alone, but requires the use of atropine to prevent bradycardia. This combination may, however, provide a more stable heart rate than that seen with neostigmine and atropine in usual doses, when these drugs are used to antagonise d-tubocurarine.
An Extensive Lumbar Epidural Block
Authors: Soni N. , Holland R.
Published: January 2019

Following lumbar epidural anaesthetic a 17-year-old primigravida developed a sensory block extending to C6 and a motor block affecting her legs, arms and intercostal muscles. The progression of clinical events suggests a subdural injection of bupivacaine.
Respiratory and Cardiovascular Responses to PEEP in Artificially Ventilated Patients after Cardiopulmonary Bypass Surgery
Authors: Dobbinson T. L. , Miller J. R.
Published: January 2019

The respiratory and haemodynamic effects of incremental levels of positive end expiratory pressure (PEEP) to 9 cm H2O were studied in ten adult patients 3-6 hours after uneventful cardiopulmonary bypass surgery. Functional residual capacity was increased and deadspace-tidal volume ratio tended to fall, the latter approaching significance at +6 and +9 cm PEEP. Thus lung volume was increased and there was a tendency to improved gas distribution to the alveoli. However there was no significant change in PaO2, alveolar-arterial oxygen tension difference or venous admixture. Cardiac index, and left ventricular strokework index were marginally depressed at 6 cm PEEP and further at 9 cm, while right atrial pressure and pulmonary artery occlusion pressure were raised at 9 cm PEEP. It would appear that low levels (3-6 cm) of PEEP do not improve gas exchange in the lungs to any worthwhile degree, and levels (6-9 cm) may impair cardiac performance.
Alveolar-Arterial Oxygen Tension Difference: A Critical Look
Authors: Torda T. A.
Published: January 2019

By rearranging the terms of the pulmonary shunt equation the physiological factors affecting alveolar-arterial oxygen tension difference can be examined. The effect of the inspired oxygen fraction and haemoglobin concentration are illustrated. It is demonstrated that there is an important cardiac output dependent term which has considerable effect. Therefore the alveolar-arterial oxygen tension difference cannot be used as a reliable measure of pulmonary function. This is illustrated with data from two case histories.
Case Report: A Complication with Intravenous Anaesthesia in a Patient with Auto-Erythrocyte Sensitisation Syndrome (Painful Bruising Syndrome)
Authors: Hales P.
Published: January 2019

Following an intravenous induction using a small bore scalp vein needle, a 59-year-old woman developed an extensive painful haematoma of the hand and arm. It was subsequently learned that the patient had the uncommon auto-erythrocyte sensitisation syndrome.
Hazards of Anaesthetic Scavenging: Case Reports and Brief Review
Authors: O'Connor D. E. , Daniels B. W. , Pfitzner J.
Published: January 2019

Two cases are presented of misadventure occurring in association with the use of anaesthetic scavenging equipment. The first case demonstrates how easily the scavenging line linking the venting port of a mechanical ventilator to the scavenging interface can become accidentally obstructed. The second case suggests that the proper use of scavenging equipment will effectively eliminate any possibility of recognising by smell an accidental overdose of volatile anaesthetic agent.

Previous reports of scavenging hazards are briefly reviewed. It is concluded from this review that scavenging suction should be‘low-vacuum’, that a relief valve must be included in the scavenging pathway proximal to any site of potential obstruction, and that the appearance and function of a scavenging interface must be simple and immediately obvious.
Repeated Administration of Suxamethonium in a Patient with Atypical Plasma Cholinesterase
Authors: Cass N. M. , Doolan L. A. , Gutteridge G. A.
Published: January 2019

The response to a range of small doses of suxamethonium was evaluated in a patient with an atypical plasma cholinesterase who required a course of electroconvulsive therapy. A dose of 0.05-0.1 mg/kg of suxamethonium is suggested as a suitable test dose in patients suspected of having an atypical plasma cholinesterase.
The Anaesthetic and Perioperative Management of the Patient Undergoing Insertion of a Peritoneo-Venous Shunt
Authors: Bettenay D. A. M. , Maddern P. J. , Oh T. E. , McGlew I. C.
Published: January 2019

The infusion of ascitic fluid from the peritoneal cavity into the central venous circulation may relieve massive intractible ascites, and improve renal function when hepatorenal syndrome is present. Preoperative preparation of these patients includes investigation of hepatic, renal, pulmonary, cardiac and neurological function, correction of electrolyte and coagulation abnormalities, restoration of normal fluid balance and the provision of supplemental vitamins and calories. Premedication is achieved with an oral benzodiazepine or an intramuscular injection of a narcotic agent. General anaesthesia is provided by thiopentone, suxamethonium, nitrous oxide, oxygen, pancuronium and a narcotic, with intermittent positive pressure ventilation. Close monitoring of cardiac, respiratory and renal function is imperative perioperatively. Postoperatively, supervision in an Intensive Care Unit is advised as complications such as cardiac failure, septicaemia and disseminated intravascular coagulation may occur.
4-Aminopyridine — A Review
Authors: Soni N. , Kam P.
Published: January 2019

4-aminopyridine is the first of the aminopyridines to be used in clinical practice. It blocks potassium channels and thereby increases acetylcholine, and possibly noradrenaline, release at nerve terminals. In man the drug has a significant action at the neuromuscular junction, but has little effect on the autonomic nervous system or muscle (smooth, skeletal, or cardiac) although such actions have been demonstrated in animals.

It may be clinically useful in the reversal of nondepolariser blockade and a role in antibiotic associated block has been proposed. It may be used effectively as an analeptic agent. It appears to be a useful therapeutic agent in myasthenia gravis and Eaton Lambert syndrome, although of limited use in botulism.

Its effects on the central nervous system are considerable. These account for the major side effects of the drug which include tremor, excitability and convulsions.
Org NC 45 Reduces Quantal Release of Acetylcholine (a Preliminary Communication)
Authors: Torda T. A. , Kiloh N.
Published: January 2019

The new neuromuscular blocker, Org NC 45 was applied to the toad sartorius nerve-muscle preparation. Measurement of the variance ratio of end-plate potentials recorded by micro-electrodes demonstrated that in concentrations greater than that required to block myoneural transmission, Org NC 45 reduced the quantal release of acetylcholine.
Flunitrazepam Increases and Diazepam Decreases the Lower Oesophageal Sphincter Tone When Administered Intravenously
Authors: Rubin J. , Brock-Utne J. G. , Dimopoulos G. E. , Downing J. W. , Moshal M. G.
Published: January 2019

Increasing the resting lower oesophageal sphincter tone is an accepted method of reducing the risk of gastro-oesophageal reflux. The effect of intravenously administered flunitrazepam and diazepam on the lower oesophageal sphincter tone were studied in 16 healthy subjects. Flunitrazepam increased this tone significantly (p < 0.05) while diazepam decreased the tone, also significantly (p < 0.005). Intravenous flunitrazepam may be a valuable sedative or premedicant, especially in patients who may develop gastro-oesophageal reflux.
Anaphylaxis to both Decamethonium and Suxamethonium
Authors: Fisher M. McD. , Chan M. C. Y.
Published: January 2019

Intradermal testing is a reliable method of determining the drug or drugs responsible for an anaphylactic reaction.1 Adequate explanation and documentation given to the patient can be effective in preventing subsequent reactions.2 The case of a patient who had a second lifethreatening reaction despite these precautions is described.
Bronchial Adenoma Mimicking Complications of Endotracheal Intubation
Authors: Him David Yeo Keat
Published: January 2019

A 39-year-old Chinese lady was admitted to hospital for an emergency caesarian section under general anaesthesia. After intubation it was discovered that there was diminished air entry to the left side.

The cause could not be elicited during anaesthesia and a postoperative chest radiograph revealed no abnormality. Subsequent tomography revealed a mass in the lumen of the left main bronchus. Biopsy of the lesion revealed an adenoid cystic carcinoma (bronchial adenoma — cylindroma type).

By causing airway obstruction with gas trapping this rare neoplasm may present as the cause of a problem mimicking more common complications of endotracheal intubation.
The New Literacy
Authors: Morgan Craig
Published: January 2019

Only with a knowledge of computers can we participate effectively in all facets of modern life. Computer literacy will enable us to keep control over our own professional activities, to contribute effectively to debate, to use the new information systems and to develop our own projects. Anaesthetists can develop this literacy by consistent reading, by doing courses, and by using computers. This paper deals with what we can learn about computer language, and methods of developing a computer project.
Humanising the Computer
Authors: Paull John D.
Published: January 2019

Many well-intentioned and potentially useful data handling computer systems fail to realise their potential because inadequate effort has been made to humanise the computer/operator interface. Programs are usually written by people who are logical thinkers, enjoy working with computers and who find satisfaction in writing their programs. Unfortunately those same programs often have to be used by people who are illogical, who fear computers and loathe having to work with them. Some suggestions for humanising the computer/operator interaction are made.
One Year's Evaluation of a System of On-line Computerisation of Anaesthetic Records Using a Computer Bureau
Authors: Roessler P. , Lambert T. F.
Published: January 2019

A system for the on-line computerisation of anaesthetic records using a computer bureau is described. The requirements of the system are a keyboard and video display unit appropriately linked to the bureau's computer.

The system was cheap and easy to install. It required no programming expertise from department members. Disadvantages included the need to change between two screens for data entry, a delay of over 8 months before satisfactory reports materialised for individuals or the department, congestion at peak times for data entry, excessive time spent on data entry, reluctance of the bureau to alter the format of the screens once they had been generated.

The cost of the system is felt to be justified by the information provided for both accreditation requirements and for department management.
Bedside Computer Programs in the Intensive Care Unit
Authors: Oh T. E. , Cameron P. D.
Published: January 2019

An inexpensive home microcomputer is used in an intensive care unit to facilitate patient management. The computer's rapid and accurate calculations are used to regulate inspired oxygen, infuse drugs and plan parenteral nutrition. Patient physiological data are processed to derive cardiovascular, respiratory and renal variables which help to monitor and evaluate patient progress.
Computerised Patient Monitoring in Intensive Care
Authors: Oh T. E. , Black J. L. , de Roach J. N. , Davis N. J.
Published: January 2019

A specially designed computerised patient-monitoring system surveys electroencephalogram and cardiovascular variables continuously, as well as up to twelve other variables at timed intervals. Special features include trend recordings, alarms, marking facilities and “suspend” monitoring. The ease of data entry and recall is an advantage.
Anomalous Action of Tubocurarine in the Tibialis Anterior Muscle of the Cat
Authors: Potter Julia M. , Edeson R. O. , Forbes A. M.
Published: January 2019

Low dose infusion of tubocurarine (20 μg/kg per min) causes an increase in muscle contraction in tibialis anterior of the cat. Tibialis anterior muscle of 13 adult cats was indirectly stimulated via the sciatic nerve using a square wave pulse of 0.2 ms duration and supramaximal voltage at 0.06 Hz. The increase is from 5-133% of control with a mean of 36%. This is sustained for a mean of 97 min, if the infusion is ceased when maximum potentiation is achieved. Duration of potentiation is decreased by increasing the frequency of stimulation. The potentiation occurs in the presence of either rising or falling concentrations of tubocurarine, and continuing the infusion results in neuromuscular blockade. One explanation of these observations is that low dose tubocurarine may interfere with presynaptic negative feedback control of acetylcholine release.
Haemodilution for Major Vascular Surgery — Using 3.5% Polygeline (Haemaccel)
Authors: Davies Michael J. , Cronin Keith D. , Domaingue Charles
Published: January 2019

Intra-operative haemodilution and autotransfusion was carried out in 32 patients having major vascular surgery. The intra-operative blood loss and peri-operative blood replacement was compared with that in 25 patients having similar surgery in whom haemodilution was considered to be contraindicated. Both groups of patients had similar mean intra-operative blood loss measured but homologous blood transfusion requirements were significantly different; 2.6 units (SD 1.9) in the haemodiluted patients compared with 6.0 units (SD 3.5) in the non-diluted patients. There was no mortality in the haemodiluted patients nor was any morbidity attributed to the procedure. Polygeline (haemaccel) was used as the diluent and proved satisfactory for this purpose.
Platelet Counts in Stored Donor Blood
Authors: Russell W. J. , Tunbridge L. J.
Published: January 2019

Platelets were counted in eight units each of one- and three-day-old blood. Counts were done both before and after the blood had passed through a standard 170 micron filter.

In the one-day-old blood, platelet counts were within the normal range. The mean count was 237,000 platelets/microlitre. Platelet counts on three-day-old blood were lower, but generally still within the normal range. The mean count was 183,000/microlitre. Only a few platelets were retained by the filter in the transfusion set; about 90% of platelets passed the filter in both the one- and three-day-old blood.

It appears that whole blood, anticoagulated with citrate/phosphate/dextrose (CPD), and stored under Australian blood bank conditions retains platelets in sufficient numbers for at least the first three days to be clinically significant. However, it remains to be determined whether satisfactory platelet activity can be expected during this time.
The Effects of Suxamethonium and D-Tubocurarine on the Pressor and Plasma Catecholamine Responses to Tracheal Intubation
Authors: Cummings M. F. , Russell W. J. , Frewin D. B. , Jonsson J. R.
Published: January 2019

Changes in mean arterial pressure (MAP) and plasma catecholamine concentrations in response to endotracheal intubation were examined in 8 patients who had received d-tubocurarine and 10 who had received suxamethonium. MAP fell after induction of anaesthesia and administration of the relaxant by a mean of 11 mmHg in those who had received suxamethonium and 19 mmHg in those who had received d-tubocurarine (p <0.05 for each). MAP rose sharply when the trachea was intubated, by a mean of 29 mmHg for the suxamethonium group, and 35 mmHg for the curare group (p <0.001 for each). A significant rise in plasma noradrenaline was also noted after intubation in each group, 51% (p <0.01) for the suxamethonium group and 28% (p <0.05) for the d-tubocurarine.

The results suggest that the fall in MAP after administration of d-tubocurarine does not attenuate the pressor response associated with intubation.
Towards Safer Transport of Sick and Injured Children
Authors: Owen H. , Duncan A. W.
Published: January 2019

A Paediatric Emergency Transport Service has been operating from the Paediatric Intensive Care Unit of the Royal Children's Hospital, Melbourne, for the last three years. The records of the first 158 patients evacuated have been analysed and are reported. Problems relating to the care of the airway and artificial airway have been the most common. The need for careful pre-transport resuscitation and stabilisation is emphasised. The educational role of a transport service both at the time of initial consultation and at the time of retrieval is stressed.
A Comparison of Methods of Cardiac Output Measurement
Authors: Woog R. H. , McWilliam D. B.
Published: January 2019

Cardiac output measurements determined by dye dilution, iced-injectate thermodilution and room temperature thermodilution were compared in man in order to assess the random error of each method and to examine the systematic error of both thermodilution methods in comparison with dye dilution.

Results showed that random error was greatest with room temperature thermodilution and least using iced thermodilution. Iced thermodilution correlated well with dye dilution, tending to overestimate cardiac output only at low flows. Room temperature thermodilution, however, overestimated cardiac output by up to 25% in the clinically important range and more so at low cardiac output.
Anaesthetic Implications of the Mucopolysaccharidoses: A Fifteen-Year Experience in a Children's Hospital
Authors: Baines David , Keneally John
Published: January 2019

Patients suffering from the mucopolysaccharidoses, most commonly Hurler's syndrome, present special problems in anaesthesia. A retrospective review of the anaesthetic management of such patients over fifteen years revealed a high incidence of airway problems. Two case histories illustrating these difficulties are presented.
Pharmacokinetic Optimisation of Aminophylline Infusions in Critically Ill Patients
Authors: Ilett K. F. , Nation R. L. , Silbert B. , Oh T. E.
Published: January 2019

The method of Chiou et al.4 was used to predict theophylline kinetics in eleven critically ill patients with either acute severe asthma or bronchoconstriction. Following the commencement of an accurately metered infusion of aminophylline, venous blood samples were taken at approximately 1, 5 hours and 7-12 hours for measurement of plasma theophylline concentration. The 1- and 5-hour levels were used to estimate total body clearance and plasma concentration of theophylline at the 7-12-hour sampling time. Using these values, the infusion rate was adjusted if necessary and the protocol repeated. Initial predictions were unreliable in two patients because of continued absorption of theophylline from pre-infusion therapy with aminophylline suppositories or slow-release theophylline tablets. In the remaining studies there was a significant correlation (y = 0.9x + 0.55, r2 = 0.93, p < 0.01, n = 19) between predicted and actual plasma concentrations at the 7-12-hour sampling time. In three patients, sequential estimates of theophylline clearance showed an approximate twofold variation and in another two patients, there was evidence of concentration-and/or time-dependent theophylline kinetics.
The Making of an Anesthesiologist: A Review of the American Scene
Authors: Ronai Ann , Shanks Colin A.
Published: January 2019

Many anaesthetists practising in Australia and New Zealand realise that differences exist in the training of their counterparts in the United States. This review attempts to highlight the differences observed by two anaesthetists who have been involved in both systems. Aspects of the American Board of Anesthesiology examination are discussed from this viewpoint.
Acute Renal Failure in the Intensive Care Unit — Clinical Considerations
Authors: Hayes James M.
Published: January 2019

The pathogenesis of acute renal failure remains uncertain. From a clinical viewpoint the magnitude of the problem of nephrotoxic acute renal failure is now recognised as is the frequency of non-oliguric acute renal failure. Advances in patient management include the use of daily dialysis, lower heparin doses, single-needle dialysis, bicarbonate-base dialysis fluid, artificial kidneys with biocompatible membranes, H2 antagonists, and the use of soft silastic Tenckhoff catheters if peritoneal dialysis is the preferred form of therapy.