bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Remote Ischaemic Preconditioning on Myocardial Injury in Patients Undergoing Off-Pump Coronary Artery Bypass Graft Surgery
Authors: Hong D. M. , Min J. J. , Kim J. H. , Sohn I. S. , Lim T. W. , Lim Y. J. , Bahk J.-H. , Jeon Y.
Published: January 2019

In several recent clinical trials on cardiac surgery patients, remote ischaemic preconditioning (RIPC) showed a powerful myocardial protective effect. However, the effect of RIPC has not been studied in patients undergoing off-pump coronary artery bypass graft surgery. We evaluated whether RIPC could induce myocardial protection in off-pump coronary artery bypass graft surgery patients. Patients undergoing elective off-pump coronary artery bypass graft surgery were randomly allocated to the RIPC (n=65) or control group (n=65). After induction of anaesthesia, RIPC was induced by four cycles of five-minute ischaemia and reperfusion on the upper limb using a pneumatic cuff. Anaesthesia was maintained with sevoflurane, remifentanil and vecuronium. Myocardial injury was assessed by troponin I before surgery and 1, 6, 12, 24, 48 and 72 hours after surgery. There were no statistical differences in troponin I levels between RIPC and control groups (P=0.172). Although RIPC reduced the total amount of troponin I (area under the curve of troponin increase) by 26%, it did not reach statistical significance (RIPC group 53.2∓72.9 hours.ng/ml vs control group 67.4∓97.7 hours.ng/ml, P=0.281).

In this study, RIPC by upper limb ischaemia reduced the postoperative myocardial enzyme elevation in offpump coronary artery bypass graft surgery patients, but this did not reach statistical significance. Further study with a larger number of patients may be needed to fully evaluate the clinical effect of RIPC in off-pump coronary artery bypass graft surgery patients.
Intravascular Haemolysis and Septicaemia Due to Clostridium Perfringens Liver Abscess
Authors: Rajendran G. , Bothma P. , Brodbeck A.
Published: January 2019

Intravascular haemolysis is a rare but serious complication of Clostridium perfringens sepsis. The outcome is usually fatal unless treatment is started early. We describe a case of survival after haemolysis and multiple organ failure in the setting of a ruptured liver abscess and sepsis caused by C. perfringens in an immunocompetent 58-year-old male.
In Situ Simulation Training for Paediatric Cardiorespiratory Arrest: Initial Observations and Identification of Latent Errors
Authors: Garden A. L. , Mills S. A. , Wilson R. , Watts P. , Griffin J. M. , Gannon S. , Kapoor I.
Published: January 2019

In response to a successful, although difficult resuscitation in one of our paediatric wards, we developed and implemented an educational program to improve the resuscitation skills, teamwork and safety climate in our multidisciplinary acute-care paediatric service. The program is ongoing and consists of didactic presentations, high-fidelity in situ simulation and facilitated debriefing to encourage reflective learning. The underlying goal, to provide this training to all staff over a two-year period, should be achieved by late 2011. In this preliminary report we describe teamwork difficulties that are commonly found during such training. These included inconsistent leadership behaviours, inadequate delegation of areas of responsibility, failure to communicate problems during the execution of technical tasks (such as difficulty opening the resuscitation trolley) and failure to challenge inadequate or inappropriate therapy (such as poor chest expansion during bag-mask ventilation). In addition, we unexpectedly discovered seven latent errors in our clinical environment during the first nine months of course delivery. The most disturbing of these was that participants repeatedly struggled to identify and overcome the locking-mechanism and tamper-proof device on a newly introduced resuscitation trolley.
Botulinum Toxin to Control an Incapacitating Tic in a Child with a Clavicular Fracture
Authors: Chen Y. , Thalayasingam P.
Published: January 2019

We present the case of an 11-year-old boy who suffered from an undefined tic disorder and incidentally sustained a traumatic fracture of the clavicle. The fracture healing course was complicated by the tic activity, and the frequency and intensity of the tics were worsened by the presence of clavicular pain. He underwent surgery and his management required the collaboration of orthopaedic surgeons, the Acute Pain Service, neurologists for tic management and rehabilitation physicians who performed the intramuscular injections of botulinum toxin. We recommend a multidisciplinary and multimodal approach to managing patients suffering from tic disorders and highlight the consideration of intramuscular injections of botulinum toxin, which were successful for this patient.
Repeated Intrathecal Administration of Ropivacaine Causes Neurotoxicity in Rats
Authors: Sun Z. H. , Xu X. P. , Song Z. B. , Zhang Z. , Wang N. , Guo Q. L.
Published: January 2019

Previous studies have shown that ropivacaine is the least neurotoxic local anaesthetic. Most of the data derive from short-term ropivacaine injection into the subarachnoid space. Intrathecal administration for a prolonged period, and the histological changes and behavioural effects of repeated intrathecal administration, have not previously been investigated. We studied the possible neurotoxicity of intrathecal injection of ropivacaine in a rat model.

Rats received 0.12 ml/kg body weight of ropivacaine at concentrations of 0.5 or 1%, or normal saline only, via an implanted intrathecal catheter at 90-minute intervals for 12 hours. On days 1, 3, 5, 7, 14 and 28, the spinal cord was examined by light and electron microscopy at the L3 level. We assessed sensory thresholds to noxious stimulation, behavioural change and protein kinase B immunoreactivity for possible neuronal injury within the spinal cord.

Ropivacaine 1% induced thermal hyperalgesia and mechanical allodynia, neuronal injury characterised by tissue oedema, proliferation of glial cells, neuronal morphology changes and degeneration and protein kinase B expression. There were no significant differences in motor function as a result of different concentrations of ropivacaine.

Repeated intrathecal injection of ropivacaine 1% can induce neurotoxicity in rats. Our data suggests that expression of protein kinase B might be involved in this neurotoxicity.
Stroke Volume Variation as a Predictor of Fluid Responsiveness in Patients Undergoing Airway Pressure Release Ventilation
Authors: Suehiro K. , Rinka H. , Ishikawa J. , Fuke A. , Arimoto H. , Miyaichi T.
Published: January 2019

We investigated the effectiveness of stroke volume variation (SVV) shown by the Vigileo-FloTrac™ system (Edwards Lifesciences, Irvine, CA) to predict fluid responsiveness in patients undergoing airway pressure release ventilation (APRV).

All 80 patients mechanically ventilated in the intensive care unit of our hospital from April to November 2010 were included in this study. After starting APRV, Ringer's lactate solution was administered for 30 minutes. Haemodynamic variables including heart rate, mean arterial pressure, cardiac index (CI), stroke volume index (SVI) and SVV were measured before and after volume loading.

SVV before volume loading was significantly correlated with absolute change in SVV (ΔSVV) and percentage change in stroke volume index (ΔSVI) after volume loading (ΔSVV: P 2=0.534; ΔSVI: P &0.05, r2=0.217). Of the 80 patients, 38 (47.5%) were responders to intravascular volume expansion (increase in CI ≥15%) and 42 (52.5%) were non-responders (increase in CI P <0.05). The optimal threshold value of SVV to discriminate between responders and nonresponders was 14% (sensitivity: 78.9%; specificity: 64.3%).

We found that SVV was able to predict fluid responsiveness in patients undergoing APRV with acceptable levels of sensitivity and specificity.
Performance of Apache III over Time in Australia and New Zealand: A Retrospective Cohort Study
Authors: Paul E. , Bailey M. , Van Lint A. , Pilcher D. V.
Published: January 2019

The Acute Physiology and Chronic Health Evaluation (APACHE) III-j model has been used for benchmarking intensive care unit (ICU) outcomes in Australia and New Zealand for over a decade. This study assessed performance of the APACHE III-j model in adult patients admitted to Australasian ICUs during a ten-year period.

Data were extracted from the Australian and New Zealand Intensive Care Society Adult Patient Database. Performance of APACHE III-j at different time points and within different age strata was evaluated by dividing the whole cohort into five ‘two-year’ groups. Calibration and discrimination were assessed by the Brier score, Hosmer-Lemeshow C and H statistics, Standardised Mortality Ratio (SMR), Cox calibration regression, calibration curves and area under the receiver operating characteristic curve (AUROC). Model performance within diagnostic categories was evaluated.

Between 1 January 2000 and 31 December 2009, 558,585 ICU admissions which met inclusion criteria were included in the analysis. The mean (standard deviation) age was 60.8 (18.4) years and 58.3% were male. Overall observed mortality was 12.6%. The mean (standard deviation) APACHE III-j predicted mortality was 14.5% (21.8). Although discrimination (as measured by AUROC) was preserved over time, all other markers of model performance showed deterioration. There was a significant decrease in SMR in eight of ten most common diagnoses examined.

This study demonstrates that performance of APACHE III-j model has deteriorated in Australasian hospitals and there is now a clear need for an updated modelling approach to improve mortality prediction, performance monitoring and quality of research undertaken in Australian and New Zealand ICUs.
The Patient Inflating Valve in Anaesthesia and Resuscitation Breathing Systems
Authors: Fenton P. M. , Bell G.
Published: January 2019

Patient inflating valves combined with self-inflating bags are known to all anaesthetists as resuscitation devices and are familiar as components of draw-over anaesthesia systems. Their variants are also commonplace in transfer and home ventilators. However, the many variations in structure and function have led to difficulties in their optimal use, definition and classification. After reviewing the relevant literature, we defined a patient inflating valve as a one-way valve that closes an exit port to enable lung inflation, also permitting exhalation and spontaneous breathing, the actions being automatic. We present a new classification based on the mechanism of valve opening/closure; namely elastic recoil of a flexible flap/diaphragm, sliding spindle opened by a spring/magnet or a hollow balloon collapsed by external pressure. The evolution of these valves has been driven by the difficulties documented in critical incidents, which we have used along with information from modern International Organization for Standardization standards to identify 13 ideal properties, the top six of which are non-jamming, automatic, no bypass effect, no rebreathing or air entry at patient end, low resistance, robust and easy to service. The Ambu and the Laerdal valves have remained popular due to their simplicity and reliability. Two new alternatives, the Fenton and Diamedica valves, offer the benefits of location away from the patient while retaining a small functional dead space. They also offer the potential for greater use of hybrid continuous flow/draw-over systems that can operate close to atmospheric pressure. The reliable application of positive end-expiratory pressure/continuous positive airway pressure remains a challenge.
Simulation Training for Rare Medications in the Intensive Care Unit—A Study with Bivalirudin
Authors: Edrich T. , Frendl G.
Published: January 2019

The purpose of this study was to assess whether simulation training can improve the clinician's ability to predict the effect of bivalirudin infusion.

Six clinicians with experience using bivalirudin and six without experience (Groups Exp and NoExp) entered predictions for partial thromboplastin time while viewing a running display of clinical data obtained retrospectively from intensive care unit patients who had received bivalirudin infusion after cardiac surgery. All clinicians entered guesses for the same sequence of 30 patients. Average guessing-errors were analysed using analysis of variance and linear regression.

All physicians evaluated 30 patients (813 partial thromboplastin time guesses overall) in less than two hours. Average errors in Groups Exp and NoExp decreased from 9.4 and 11.7 seconds in the first tercile, to 8.2 and 8.4 seconds in the last tercile of patients, respectively. The guessing-errors of Group NoExp were significantly higher than Group Exp in the first and second terciles, with no significant difference in the third tercile. Linear regression indicated a significantly steeper learning curve in Group NoExp than Exp.

Brief simulation training using retrospective patient data improved the ability of inexperienced clinicians to predict the effect of bivalirudin as compared to experienced clinicians.
Patient Recollections of Perioperative Anaesthesia Risks
Authors: Gillies A. , Gillies R. , Weinberg L.
Published: January 2019

There is widespread variation as to the method of presentation of informed anaesthetic consent with little empirical data on the nature of communication and how much information is retained. At a dedicated anaesthesia pre-admission clinic, 149 patients undergoing elective surgery under general anaesthesia were both verbally informed and shown written information about four major and three minor anaesthesia risks. The major risks were death, pneumonia, heart attack and stroke. The minor risks were dental damage, nausea and vomiting. On the day of scheduled surgery, retention of information about these anaesthetic risks was examined. Thirty-eight patients (26%) could not recall any anaesthesia risks, 55 patients (37%) could not recall any major risks and 126 patients (84%) could not recall any minor risks. Our findings indicate that patients should receive a second explanation on the day of surgery, even if informed consent was provided only two weeks earlier.
Differentiating Athlete's Heart from Inherited Cardiac Pathology: The Challenge of Repolarisation Abnormalities Presenting during Anaesthesia
Authors: Dzendrowskyj P. , Hamilton B. , Wilson M. G.
Published: January 2019

This case report describes an asymptomatic healthy male professional athlete who underwent general anaesthesia for a routine orthopaedic operation. Peri-procedure, pronounced ST elevation suggestive of myocardial ischaemia manifested on the electrocardiogram lasting for four hours post-procedure, upon which the athlete developed deep and diffuse inferolateral T-wave inversion. These changes resolved spontaneously and the patient remained clinically stable throughout. This case demonstrates the clinical conundrum facing anaesthetists attempting to differentiate between repolarisation anomalies that are commonly observed in high-level athletes and those of inherited cardiac pathology, namely hypertrophic cardiomyopathy, which is the leading cause of sudden cardiac death in young athletes.
A Comparison of Doubutamine and Levosimendan on Hepatic Blood Flow in Patients with a Low Cardiac Output State after Cardiac Surgery: A Randomised Controlled Study
Authors: Alvarez J. , Baluja A. , Selas S. , Otero P. , Rial M. , Veiras S. , Caruezo V. , Laboada M. , Rodriguez I. , Caslroagudin J. , Lome S. , Rodriguez A. , Rodriguez J.
Published: January 2019

Liver dysfunction due to a low cardiac output state after cardiac surgery is associated with a poor prognosis, but whether one inotrope is superior to another in improving hepatic perfusion remains uncertain. This study compared the systemic and hepatic haemodynamic effects of levosimendan to dobutamine in patients with a low cardiac output state (cardiac index < 2.2 1/min/m2) after on-pump cardiac surgery. A total of 25 patients were randomised to receive either an intravenous bolus of levosimendan (12 μg/kg) over 15 minutes, followed by an infusion of 0.2 μg/kg/min for 24 hours, or an infusion of dobutamine 7.5 μg/kg/min for 24 hours and completed the study. The systemic and hepatic haemodynamics at 24 and 48 hours were all better after levosimendan than dobutamine (dobutamine group: cardiac index (1/min/m2)=2.51 [standard deviation ±0.29], 2.40±0.23; portal vein flow (ml/min): 614.0± 124.7, 585.9±144.8; pulsatility index: 2.02±0,28, 2.98±0.27 versus the levosimendan group: cardiac index: 3.02± 0.27, 2.98± 0.30; portal vein flow: 723.0± 143.5, 702.9±117.8; pulsatility index: 1.71 ±0.26,1.73 ±0.27). The improvement in portal vein blood flow at 48 hours was significantly better after levosimendan than dobutamine (41% vs. 11% increment from baseline, P<0.05). In addition, there was a significant reduction in hepatic artery resistance after levosimendan but not dobutamine (resistance index reduction 6.5% vs. 0%, P<0.05). In summary, levosimendan can be considered as a selective liver vasodilator and can improve hepatic blood flow through both the hepatic artery and portal venous system, whereas dobutamine can only improve the portal venous blood flow without vasodilating the hepatic artery.
Effects of Prolonged Mechanical Ventilation with a Closed Suction System on Endotracheal Tube Resistance and its Reversibility by a Closed Suction Cleaning System
Authors: Adi N. A. , Tomer N. T. , Bergman G. B. , Kishinevsky E. K. , Wyncoll D. W.
Published: January 2019

The study objective was to evaluate endotracheal tubes (ETT) from extubated adult patients and compare them to new, unused, size–matched control tubes for changes in inspiratory resistance (Rinsp) and peak inspiratory pressure (PIP) before and immediately after suctioning with the Airway Medix Closed Suction System (AMCSS) (Biovo Technologies, 2013 Tel Aviv, Israel). Sixteen ETTs were recovered from predominantly medical patients who had required intubation and mechanical ventilation for more than 12 hours. ETTs were evaluated within 4.5 hours of extubation. Readings were taken during square wave flow, at rates of 40 and 60 1/minute. Cleaning of extubated ETTs using the AMCSS was able to restore them to almost original conditions in terms of Rinsp and PIP. The examined ETTs included tubes of various sizes ranging from internal diameter (ID) 7 to 8.5 mm and intubation periods ranging from 12 hours to 21 days. The mean Rinsp for the used and uncleaned ETTs was equivalent to 275% of the Rinsp of sized-matched new and unused ETTs. For 8 mm ID ETTs this was comparable to a measured Rinsp of a 5 mm tube. Following a single cleaning episode with the AMCSS, Rinsp decreased, regaining an effective ETT ID of a 7.5 to 8 mm tube. A single suctioning episode with this device resulted in a significant reduction in Rinsp, virtually restoring original flow variable values. The AMCSS represents a novel technology in closed suction systems, designed to achieve more effective inner lumen cleaning in prolonged mechanical ventilation.
Assessment of the Plethysmographic Variability Index as a Predictor of Fluid Responsiveness in Critically Ill Patients: A Pilot Study
Authors: Baker A. K. , Partridge R. J. O. , Litton E. , Ho K. M.
Published: January 2019

Optimising intravascular volume in patients with hypotension requiring vasopressor support is a key challenge of critical care medicine. The optimal haemodynamic parameter to assess fluid responsiveness in critically ill patients, particularly those requiring a noradrenaline infusion and mechanical ventilation, remains uncertain. This pilot study assessed the accuracy of the plethysmographic variability index (PVI), (Radical-7 pulse co-oximeter, Masimo®, Irvine, CA, USA) in predicting fluid responsiveness in 25 patients who required noradrenaline infusion to maintain mean arterial pressure over 65 mmHg and were mechanically ventilated with a ‘lung-protective’ strategy, and whether administering a fluid bolus was associated with a change in PVI (Δ PVI). In this study, fluid responsiveness was defined as an increase in stroke volume of greater than 15% after a 500 ml bolus of colloid infusion over 20 minutes. Of the 25 patients included in the study, only 12 (48%) were considered fluid responders. As static haemodynamic parameters, PVI, central venous pressure and inferior vena cava distensibility index were all inaccurate at predicting volume responsiveness with PVI being the least accurate (area under the receiver operating characteristic curve=0.41, 95% confidence interval 0.18 to 0.65). However, fluid responsiveness was associated with a change in PVI, but not a change in heart rate or central venous pressure. This association between A PVI and fluid responsiveness may be a surrogate marker of improved cardiac output following a fluid bolus and warrants further investigation.
A Comparison between Total Intravenous Anaesthesia using Propofol plus Remifentanil and Volatile Induction/Maintenance of Anaesthesia using Sevoflurane in Children Undergoing Flexible Fibreoptic Bronchoscopy
Authors: Chen L. , Yu L. , Fan Y. , Manyande A.
Published: January 2019

Flexible fibreoptic bronchoscopy is an important tool in the evaluation and management of paediatric respiratory disease. Total intravenous anaesthesia (TIVA) and volatile agent induction and maintenance of anaesthesia (VIMA) are commonly used for these procedures. The aim of this study was to determine which is superior for children undergoing flexible fibreoptic bronchoscopy. The study included two phases. In Phase 1, ED99 of propofol in TIVA and ED99 of sevoflurane in VIMA were first determined. In Phase 2, 50 children aged from one to three years were recruited and randomly assigned to either a TIVA or a VIMA group. An ED99 dose of propofol with remifentanil was administered to the TIVA group and sevoflurane to the VIMA group. Haemodynamic variables, stress hormone responses, anaesthesia profiles, adverse reactions and physicians’ levels of satisfaction were compared between the two groups. The ED99 values of propofol in the TIVA group and sevoflurane in the VIMA group were 8.9 μg/ml and 6.8% respectively. Haemodynamic variables and stress hormone levels were higher in the VIMA group than in the TIVA group. Agitation and coughing also occurred less frequently in the TIVA group. In addition, physicians’ levels of satisfaction were greater in the TIVA group. Our results suggest that TIVA with propofol plus remifentanil is superior to VIMA using sevoflurane alone for children undergoing flexible fibreoptic bronchoscopy.
Estimation of Glomerular Filtration Rate to Adjust Vancomycin Dosage in Critically Ill Patients: Superiority of the Chronic Kidney Disease Epidemiology Collaboration Equation?
Authors: Conil J. M. , Georges B. , Breden A. , Ruiz S. , Cougot P. , Fourcade O. , Saivin S.
Published: January 2019

The purpose of this study was to determine the best estimate of glomerular filtration rate (GFR) to adjust vancomycin (VAN) dosage in critically ill patients. Seventy-eight adult intensive care unit patients received a 15 mg/kg loading dose of VAN plus a 30 mg/kg/day continuous infusion. Steady-state concentration was measured 48 hours later and the dose was adjusted to obtain a target concentration ranging from 20 to 25 mg/1. GFR was estimated by measured creatinine clearance (CLCR), Cockcroft, Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. The required dose providing the target concentration was 36±17 mg/kg/day. The first dosage had to be increased in 51% of all patients and in 84% of trauma patients (highest GFR), but had to be decreased in 17% of patients. The closest relationship between clearances of vancomycin was observed with CKD-EPI to GFR. The correlation between clearances of vancomycin and measured CLCR was significant but was rather poor with Cockcroft and Modification of Diet in Renal Disease equation. On the Bland and Altman plots, measured CLCR provided a lower bias but a larger confidence interval and a weaker precision than CKD-EPI. For VAN dose adjustments in intensive care unit patients, Cockcroft formula and Modification of Diet in Renal Disease should be used with caution. In clinical practice, the physician does not have at their disposal the patient's measured CLCR when prescribing. The CKD-EPI appears to be the best predictor of clearances of vancomycin for calculation of a therapeutic VAN regimen.
Seduced by a P-Value…
Authors: Twain Mark , Mcilroy D.
Published: January 2019

“It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so”
Evaluation of Differences in Patient and Physician Perception of Benefit and Risks of Aspirin and Antifibrinolytic Therapy in Cardiac Surgery
Authors: Myles P. S. , Thompson G. , Fedorow C. , Farrington C. , Sheridan N.
Published: January 2019

It is unclear whether physicians and patients have similar concerns and preferences when considering benefit and risks of aspirin and antifibrinolytic therapy for cardiac surgery. We surveyed both groups to ascertain their perceptions and preferences for treatment in this setting. Both preoperative and postoperative cardiac surgical patients and the physician craft groups caring for them (cardiology, surgery, anaesthesia/critical care), were provided with estimates of benefits and risks of aspirin and antifibrinolytic therapy. All study participants were asked to stipulate the minimal absolute risk reduction required for them to agree to such therapy. When compared with the cardiac surgical patients they treat, physicians required a smaller thrombotic risk reduction with aspirin whilst accepting its known increased risk of bleeding. This was significantly different in a high-risk stroke setting (incidence 5%) where the required relative risk reduction with aspirin use for physicians was 20% versus patients 40% ( P <0.001); and for myocardial infarction, physicians 20% versus patients 36% ( P=0.051). For antifibrinolytic therapy, the tolerated increased relative risk of stroke for physicians was 20% versus patients 10% ( P=0.004), and for myocardial infarction, physicians 16.7% versus patients 4.2% ( P <0.001). The three physician craft groups had comparable tolerances of thrombotic risk. Patient and physician preferences for perioperative aspirin and antifibrinolytic therapy sometimes differ based on risk benefit analysis.
Predicting Patients at Risk of Early Postoperative Adverse Events
Authors: Seglenieks R. , Painter T. W. , Ludbrook G. L.
Published: January 2019

Adverse events after surgery are common. Identification of markers of at-risk patients may facilitate efficient and effective perioperative resource allocation. This pilot study aimed to identify simple preoperative factors associated with postoperative adverse events. In 1291 surgical patients, the relationship between patient and surgical factors and adverse events in the post-anaesthesia care unit was examined using binomial logistic regression analysis. Adverse events in the postoperative care unit were common, including desaturation (13.6%), hypotension (5.8%) and apnoea (5.5%), with 19.9% of cases requiring attendance by an anaesthetist to manage unexpected complications. Average length-of-stay in the post-anaesthesia care unit was 120 minutes and prolonged stay for medical reasons was common. A number of patient and surgical factors, including surgical complexity, preoperative arrhythmia, previous anaesthetic issues and heart failure were strongly associated with these adverse events. Areas under receiver operating characteristic curves ranged from 0.63 to 0.80. Patients with adverse events in the post-anaesthesia care unit appeared to have a higher risk of intervention in postoperative wards from a medical emergency or intensive care unit team. Our preliminary findings suggest that preoperative identification of key factors may have utility in determining risk of early postoperative problems and hence, aid perioperative planning.
Difficult Airway Equipment: A Survey of Standards across Metropolitan Perth
Authors: Alakeson N. , Flett T. , Hunt V. , Ramgolam A. , Reynolds W. , Hartley K. , Hegarty M. , Von Ungern-Sternberg B. S.
Published: January 2019

The importance of appropriate equipment to manage the difficult airway has been highlighted by the publication of the Australian and New Zealand College of Anaesthetists (ANZCA) guidelines in 2012. We set out to audit compliance with these guidelines in all public and private sites providing general anaesthesia in metropolitan Perth. Public and private healthcare websites identified 39 sites of which 37 were studied. Institutional and ethics approval was obtained. A tick-box design audit tool, based on the ANZCA guidelines, was used to collect information regarding the dedicated difficult airway container (DDAC) at each site. As recommended in the guidelines, only equipment within the DDAC was considered. Further data about each site, including the number of theatre suites, satellite anaesthetic areas, use of capnography and categories of patients treated (adult, obstetric and paediatric) were collected. An adult DDAC was found at 92% of all sites, but none of the sites had all the essential equipment listed in the ANZCA guidelines. There was limited provision of adult difficult airway equipment within private sites compared to public, and less provision of paediatric difficult airway equipment across all sites treating paediatric patients in metropolitan Perth. Capnography was available in 76% of post anaesthesia care units and used regularly in 27%. Adherence to the ANZCA guidelines regarding the DDAC could be improved. Standardised equipment across a metropolitan region would be of value in the management of the difficult airway.
The Association between Early Arterial Oxygenation and Mortality Post Cardiac Surgery
Authors: Sutton A. D. J. , Bailey M. , Bellomo R. , Eastwood G. M. , Pilcher D. V.
Published: January 2019

Many studies have been conducted to investigate the relationship between hyperoxia and mortality in cohorts of intensive care unit (ICU) patients with varied and often contradictory results. The impact of early hyperoxia post ischaemia remains uncertain in various ICU cohorts. We aimed to investigate the association between arterial oxygenation (PaO2) in the first 24 hours in ICU and mortality in patients following cardiac surgery, using a retroespective cohort study of data from the Australian and New Zealand Intensive Care Society adult patient database. Participants were adults admitted to the ICU following cardiac surgery in Australia and New Zealand between 2003 and 2012. Patients were divided according to worst PaO2 level or alveolar-arterial O2 gradient in the 24 hours from admission. We defined ‘hyperoxia’ as PaO2 ≥300 mmHg, ‘hypoxia/poor O2 transfer’ as either PaO2 <60 mmHg or ratio of PaO2 to fraction of inspired oxygen <300 and ‘normoxia’ as between hypoxia and hyperoxia. The primary outcome was mortality at hospital discharge. Secondary outcomes were ICU mortality and ICU and hospital length-of-stay. Of the 83,060 patients 12,188 (14.7%) had hyperoxia, 54,420 (65.5%) had hypoxia/poor O2 transfer and 16,452 (19.8%) had normoxia. There was no association between hyperoxia and in-hospital or ICU mortality compared to normoxia. There was a small increased hospital and ICU length-of-stay for hyperoxic compared to normoxic patients. We concluded that there was no association between mortality and hyperoxia in the first 24 hours in ICU after cardiac surgery.
Anaesthesia Priorities for Australian and New Zealand Medical School Curricula: A Delphi Consensus of Academic Anaesthetists
Authors: Overton M. J. , Smith N. A.
Published: January 2019

The role of anaesthetists has expanded and evolved to include critical care, perioperative and pain medicine and general clinical skills, as well as operating theatre-based clinical anaesthesia. Across Australia and New Zealand, these topics are taught to varying degrees, however no uniform curriculum or standardisation exists between universities. In this study, we used a Delphi technique to develop consensus-based priorities to guide medical educators when reviewing and implementing student anaesthesia curricula. A range of appropriate content has been defined, as well as details relating to duration, timing, teaching environment, faculty, feedback and assessment methods. Future enquiry to assess the efficacy of future and current teaching practices is needed to facilitate continued improvement.
Complications of Intra-Aortic Balloon Pump Use: Does the Final Position of the IABP Tip Matter?
Authors: Siriwardena M. , Pilbrow A. , Frampton C. , Macdonald S. M. , Wilkins G. T. , Richards A. M.
Published: January 2019

We report results of a retrospective review of intra-aortic balloon pump (IABP) use in two Australasian centres and evaluate the effect of final IABP tip position on outcome. Indications for counterpulsation, patient demographics and in-hospital outcomes and complications were retrospectively collected. The chest X-ray reports provided the ‘final’ position of the IABP tip. The position was defined as acceptable (tip was seen just below the aortic arch, at T2–T5 vertebrae), malpositioned (tip >5 cm below aortic arch or at T5–T6) or severely malpositioned (tip >10 cm below aortic arch or at T7 or below). Major complications were considered a composite of death secondary to IABP, major limb ischaemia, major IABP malfunction, balloon rupture or haemorrhage, severe renal dysfunction (rise in creatinine >200 μmol/l), stroke and mesenteric ischaemia. Six hundred and forty-five cases were reviewed. The overall major complication rate was 26.2% and 24.3%. Severe renal impairment was the most common complication (16.6%), and second, severe catheter dysfunction (5.4%). Final IABP position was acceptable in 39.9%, malpositioned in 11.1%, severely malpositioned in 6.7% and unavailable for 42.4%. Logistic regression analysis showed IABP tip malposition (compared with satisfactory position odds ratio=3.9 [95% confidence interval=2.0–7.6, P <0.001] and severely malpositioned odds ratio=13.0 [95% confidence interval=5.3–31.7, P <0.001]) were associated with major complications more than the presence of shock (odds ratio=3.8, confidence interval 2.1–6.8 P <0.001). The acceptance of a less than ideal final position was highly predictive of morbidity directly related to IABP device therapy.
Effect of Different Phenylephrine Bolus Doses for Treatment of Hypotension during Spinal Anaesthesia in Patients Undergoing Elective Caesarean Section
Authors: Mohta M. , Harisinghani P. , Sethi A. K. , Agarwal D.
Published: January 2019

The efficacy of phenylephrine might be improved by giving doses higher than that traditionally used (100 μg). This study compared the effects of three initial bolus doses of intravenous phenylephrine; 100 μg (group P100), 125 μg (group P125) and 150 μg (group P150), for the treatment of post-spinal hypotension in patients undergoing elective caesarean delivery. If hypotension was not corrected by this dose, additional boluses of 25 μg were given every minute. Further hypotensive episodes were treated with half the initial bolus dose, followed by 25 μg boluses, as required. Umbilical arterial and venous blood samples were obtained for blood gas analysis and Apgar scores recorded. One hundred and twenty subjects (40 per group) who developed post-spinal hypotension (75%) were included in this randomised, double blind trial. Although systolic blood pressure was higher at certain time-points after 150 μg phenylephrine, there were no statistically significant differences in the effectiveness of the first bolus of phenylephrine to treat hypotension (85%, 95% and 95% in groups P100, P125 and P150, respectively, P=0.215); the additional dose of phenylephrine after the first bolus ( P=0.810); the number of additional boluses ( P=0.318) or of hypotensive episodes ( P=0.118). There were no significant differences in the number of patients developing reactive hypertension or bradycardia, in maternal side-effects or in neonatal outcomes. Although the study may have been underpowered, initial phenylephrine bolus doses of 100 μg, 125 μg and 150 μg did not significantly differ in efficacy to treat post-spinal hypotension in these patients.
The Time Taken for the Regional Distribution of Ventilation to Stabilise: An Investigation Using Electrical Impedance Tomography
Authors: Caruana L. R. , Paratz J. D. , Chang A. , Barnett A. G. , Fraser J. F.
Published: January 2019

Electrical impedance tomography is a novel technology capable of quantifying ventilation distribution in the lung in real time during various therapeutic manoeuvres. The technique requires changes to the patient's position to place the electrical impedance tomography electrodes circumferentially around the thorax. The impact of these position changes on the time taken to stabilise the regional distribution of ventilation determined by electrical impedance tomography is unknown. This study aimed to determine the time taken for the regional distribution of ventilation determined by electrical impedance tomography to stabilise after changing position. Eight healthy, male volunteers were connected to electrical impedance tomography and a pneumotachometer. After 30 minutes stabilisation supine, participants were moved into 60 degrees Fowler's position and then returned to supine. Thirty minutes was spent in each position. Concurrent readings of ventilation distribution and tidal volumes were taken every five minutes. A mixed regression model with a random intercept was used to compare the positions and changes over time. The anterior-posterior distribution stabilised after ten minutes in Fowler's position and ten minutes after returning to supine. Left-right stabilisation was achieved after 15 minutes in Fowler's position and supine. A minimum of 15 minutes of stabilisation should be allowed for spontaneously breathing individuals when assessing ventilation distribution. This time allows stabilisation to occur in the anterior-posterior direction as well as the left-right direction.
Safe Duration of Postoperative Monitoring for Malignant Hyperthermia Patients Administered Non-Triggering Anaesthesia: An Update
Authors: Barnes C. , Stowell K. M. , Bulger T. , Langton E. , Pollock N.
Published: January 2019

The postoperative care of malignant hyperthermia (MH) patients is subject to international variation, with a paucity of data in the literature to guide management. Over a series of three studies, our aim was to evaluate whether MH-susceptible patients (and relatives who had not yet been investigated), who had received a non-triggering anaesthetic, could be managed in the same way as the standard surgical population. Following a retrospective study, 206 anaesthetics were administered in a prospective second study to MH-susceptible/related individuals who were monitored for a minimum of one hour in the post anaesthesia care unit and a further 90 minutes in a step-down facility. No problems relating to MH were encountered. The postoperative monitoring time was subsequently changed and, in a third study, patients were managed no differently from standard surgical patients. One hundred and twenty-five anaesthetics were administered with no evidence of problems. This data shows that standard postoperative monitoring times are safe and appropriate in MH-susceptible patients.
Impact of Increasing Overnight Intensive Care Unit Registrar Staffing on Duration of Intubation of Elective Cardiac Surgery Patients
Authors: Durie M. L. , Darvall J. N. , Rechnitzer T. , Tacey M. A.
Published: January 2019

It is unclear whether increases to overnight junior medical staffing levels can improve ICU patient outcomes. We conducted a retrospective cohort study before and after the introduction of a third overnight ICU registrar at a 24-bed metropolitan ICU in February 2012. We hypothesised that this change would be associated with decreased intubation time for elective cardiac surgery patients and an increase in the proportion of these patients being extubated during the overnight period. All elective cardiac surgery patients were included from two temporally matched six-month periods (May to October) in 2011 and 2012. The primary outcome was median duration of intubation, and the secondary outcome was proportion of patients extubated during the ‘overnight’ period (2200 to 0700). A total of 142 and 188 patients were included in the control and intervention cohorts, respectively. Median (IQR) intubation time was 8.7 (6.6 to 14.5) hours in the control cohort and 8.2 (6.0 to 13.4) hours in the intervention cohort, with no significant difference between groups ( P=0.40). The proportion of elective cardiac surgery patients extubated during the overnight period was similar, 54.2% in the control group compared to 50.0% in intervention group ( P=0.45). In our unit, increasing overnight ICU registrar staffing levels was not associated with a significant reduction in duration of intubation for elective cardiac surgery patients or a reduction in the proportion of these patients extubated overnight. This is likely due to factors other than medical staffing levels influencing timing of extubation of these patients.
Infraclavicular Axillary Vein Cannulation using Ultrasound in a Mechanically Ventilated General Intensive Care Population
Authors: Glen H. , Lang I. , Christie L.
Published: January 2019

Central venous catheter (CVC) insertion is commonly undertaken in the ICU. The use of ultrasound (US) to facilitate CVC insertion is standard and is supported by guidelines. Because the subclavian vein cannot be insonated where it underlies the clavicle, its use as a CVC site is now less common. The axillary vein, however, can be seen on US just distal to the subclavian vein and placement of a CVC at this site gives a result which is functionally indistinguishable from a subclavian CVC. We evaluated placement of US-guided axillary CVCs in mechanically ventilated intensive care patients. Data were collected for 125 consecutive US-guided axillary CVC procedures in ventilated patients in an adult intensive care setting. All lines were inserted using real-time US guidance with an out-of-plane technique. One hundred and twenty-five procedures occurred in 119 patients. Successful line placement was achieved in 117 out of 125 (94%) procedures. Complications included four procedures that required repeating due to catheter malposition and one arterial puncture. The median number of attempts per procedure was one (IQR 1 to 2). Thirty-nine (31%) patients had a body mass index of 30 or above, 43 (34%) patients had a coagulopathy and 70 (56%) patients had significant ventilator dependence (FiO2 of 0.5 or above, or positive end expiratory pressure 10 cmH20 or above). The technique of US-guided axillary CVC access can be undertaken successfully in ventilated intensive care patients, even in challenging circumstances. Taken together with existing work on the utility and safety of this technique, we suggest that it be adopted more widely in the intensive care population.
Anti-Seizure Prophylaxis in Critically Ill Patients with Traumatic Brain Injury in an Intensive Care Unit
Authors: Sundararajan K. , Milne D. , Edwards S. , Chapman M. J. , Shakib S.
Published: January 2019

The objectives of this prospective observational study were to determine the proportion of patients with traumatic brain injury who received effective anti-seizure prophylaxis. The study was conducted in a tertiary level ICU of a major trauma referral centre between February 2012 and August 2013. A total of 2361 patients were admitted to the ICU in this study period, of whom 125 patients (index) with traumatic head injury were included in this study. The patients had a mean age of 45 years (SD=19), a mean score on the Glasgow Coma Scale of 9 (SD=4), a mean injury severity score of 27 (SD=13) and a mean APACHE III score of 55 (SD=27). Only 13.6 % (17 of 125) of patients were given anti-seizure prophylaxis and phenytoin levels were measured in 9.6% (12 of 125). Although all 12 patients achieved an effective concentration for phenytoin therapy (>40 μmol/l) after the loading dose, no patient had their target concentration consistently maintained in the recommended therapeutic range (40 to 80 μmol/l) throughout the seven-day monitoring period. There was wide fluctuation in phenytoin levels in the patients in this study. Twenty-two (18%) of the index patients had post-traumatic seizures, indicating a high prevalence for this study. Poor compliance with guidelines could possibly explain this phenomenon. Future studies are needed to look at the dosing and monitoring of phenytoin and/or alternative anti-seizure prophylaxis in patients with traumatic brain injury.
Pain Relief in Childbirth: Changing Historical and Feminist Perspectives
Authors: Skowronski G. A.
Published: January 2019

Pain during human childbirth is ubiquitous and severe. Opium and its derivatives constitute the oldest effective method of pain relief and have been used in childbirth for several thousand years, along with numerous folk medicines and remedies. Interference with childbirth pain has always been criticised by doctors and clergy. The 19th century saw the introduction of three much more effective approaches to childbirth pain; diethyl ether, chloroform and nitrous oxide. Access to pain relief was demanded by the first wave of feminist activists as a woman's right. They popularised the use of ‘twilight sleep’, a combination of morphine and scopolamine, which fell into disrepute as its adverse effects became known. From the 1960s, as epidural analgesia became more popular, a second wave of feminists took the opposite position, calling for a return to non-medicalised, female-controlled, ‘natural’ childbirth and, in some cases, valorising the importance of the pain experience as empowering for women. However, from the 1990s, a third wave of feminist thought has begun to emerge, revalidating a woman's right to choose a ‘technological’, pain-free birth, rather than a ‘natural’ one, and regarding this as a legitimate feminist position.
Some Reminiscences from the Archives—The Australian Society of Anaesthetists Newsletter of April 1971
Authors: Brown T. C. K.
Published: January 2019

Comments are made about the items of news and some of the personalities involved from a historical perspective in the Australian Society of Anaesthetists Newsletter of April 1971.
Anaesthesia and Serum Creatine Phosphokinase Levels in Patients with Duchenne's Pseudohypertrophic Muscular Dystrophy
Authors: Richards W. C.
Published: January 2019

Forty-three patients with Duchenne's pseudohypertrophic muscular dystrophy receiving a total of 61 general anaesthetics were reviewed to assess the effect of the anaesthetic with particular regard to rise in temperature and its relationship, if any, to serum creatine phosphokinase (C.P.K.) levels.

All popular forms of anaesthetic were administered to these patients, who had a wide range of C.P.K. levels. No patient developed hyperpyrexia or had a cardiac arrest.

The features of Duchenne's dystrophy are described, the complications reviewed in the literature are outlined, and some recommendations about the anaesthetic management are made.
Methohexitone-Induced Convulsions in Epileptics
Authors: Male C. G. , Allen E. M.
Published: January 2019

The risk of precipitating a convulsion in epileptic patients with methohexitone has been judged to vary widely. This article reports such complications arising during methohexitone-activated E.E.G. recording in a series of 48 epileptic patients from whom anticonvulsant medication was withheld. Two patients developed grand mat convulsions during induction with methohexitone 1·0%. Two others exhibited status epilepticus of the petit mat type and one of the myoclonic type, after stopping an infusion of 0·09% methohexitone. The specificity for methohexitone-induced convulsions in epileptics or crypto-epileptics is supported by a review of the literature.