bluuebunny/crossref_metadata_2025 huggingface dataset:
Outcome of Patients Receiving High Dose Vasopressor Therapy: A Retrospective Cohort Study
Authors: Jenkins C. R. , Gomersall C. D. , Leung P. , Joynt G. M.
Published: January 2019

The aim of this study was to determine the hospital survival of patients receiving high doses of catecholamines.

A retrospective observational study was conducted in a 22-bed multidisciplinary adult intensive care unit of a tertiary referral university hospital. All patients (n = 64) receiving >100 μg/min of adrenaline or noradrenaline or adrenaline and noradrenaline combined over a one-year period were studied to determine survival to intensive care unit and hospital discharge. Four patients survived to intensive care unit discharge and hospital discharge (6.25%, 95% CI 0.3 to 12.2%). Survival was 3.3% (95% CI 0 to 7.9%) in the subgroup of 60 patients who received >100 μg/min noradrenaline and 3.6% (95% CI 0 to 8.6%) in the 55 patients who received >2 μg/kg/min noradrenaline. None of the 32 patients who received >200 μg/min noradrenaline survived.

We conclude that the survival of patients requiring high doses of catecholamines is poor, but the use of such doses is probably not futile. It remains for individual clinicians, patients and their surrogates to decide whether use of high doses of vasopressor is appropriate, given the low probability of survival.
Video and Optic Laryngoscopy Assisted Tracheal Intubation – the New Era
Authors: Thong S. Y. , Lim Y.
Published: January 2019

With advances in technology, videoscopy and optic intubation have been gaining popularity, particularly in patients with difficult airways or as rescue devices in failed intubation attempts. Their routine use is, however, an uncommon occurrence. This review paper will summarise some of those newly developed devices currently available to assist tracheal intubation, their advantages, disadvantages when compared with the conventional laryngoscope and finally, evidence to support their use in both elective and emergency airway management.
Airway Obstruction due to a Pre-vertebral Haematoma following Difficult Central Line Insertion – Implications for Ultrasound Guidance and Review of the Literature
Authors: Udy A. , Senthuran S. , Lipman J.
Published: January 2019

We describe a case of airway obstruction secondary to a large pre-vertebral cervico-mediastinal haematoma following failed attempts at insertion of an internal jugular central venous line. The need for a high index of suspicion to diagnose this injury and early aggressive intervention to manage it are outlined. The role of ultrasound guidance in preventing such a complication is reviewed, as well as other possible mechanisms of haematoma development.
Equivalent Metabolic Acidosis with Four Colloids and Saline on Ex Vivo Haemodilution
Authors: Morgan T. J. , Vellaichamy M. , Cowley D. M. , Weier S. L. , Venkatesh B. , Jonest M. A.
Published: January 2019

Colloid infusions can cause metabolic acidosis. Mechanisms and relative severity with different colloids are incompletely understood. We compared haemodilution acid-base effects of 4% albumin, 3.5% polygeline, 4% succinylated gelatin (all weak acid colloids, strong ion difference 12 mEq/l, 17.6 mEq/l and 34 mEq/l respectively), 6% hetastarch (non-weak acid colloid, strong ion difference zero) and 0.9% saline (crystalloid, strong ion difference zero). Gelatin weak acid properties were tracked via the strong ion gap.

Four-step ex vivo dilutions of pre-oxygenated human venous blood were performed to a final [Hb] near 50% baseline. With each fluid, base excess fell to approximately −13 mEq/l. Base excess/[Hb] relationships across dilution were linear and direct (R2 ≥0.96), slopes and intercepts closely resembling saline. Baseline strong ion gap was −0.3 (2.1) mEq/l. Post-dilution increases occurred in three groups: small with saline, hetastarch and albumin (to 3.5 (02) mEq/l, 4.3 (0.3) mEq/l, 3.3 (1.4) mEq/l respectively), intermediate with polygeline (to 12.2 (0.9) mEq/l) and greatest with succinylated gelatin (to 20.8 (1.4) mEq/l).

We conclude that, despite colloid weak acid activity ranging from zero (hydroxyethyl starch) to greater than that of albumin with both gelatin preparations, ex vivo dilution causes a metabolic acidosis of identical severity to saline in each case. This uniformity reflects modifications to the albumin and gelatin saline vehicles, in part aimed at pH correction. By proportionally increasing the strong ion difference, these modifications counter deviations from pure saline effects caused by colloid weak acid activity. Extrapolation in vivo requires further investigation.
Ease of Proseal Laryngeal Mask Airway Insertion and its Fibreoptic view after Placement using Gum Elastic Bougie: A Comparison with Conventional Techniques
Authors: Taneja S. , Agarwal M. , Dali J. S. , Agrawal G.
Published: January 2019

The Proseal Laryngeal Mask Airway (PLMA) is routinely inserted by the digital and introducer tool techniques but a newer Gum Elastic Bougie (GEB) guided insertion technique has been described.

The aims and objectives were to compare the ease of PLMA insertion and fibreoptic view of PLMA after placement using GEB and conventional techniques.

Ninety-six ASA I or II patients of either gender, aged 18 to 60 years, scheduled for elective surgery under general anaesthesia in the supine position were included in this study. Following induction of anaesthesia, a PLMA was inserted using a GEB, introducer tool or digital technique in Groups G, I and D respectively (n=32). Correct placement of the PLMA was confirmed by using clinical tests along with fibreoptic assessment. Ease of PLMA insertion was assessed by the number of attempts, time taken and number of patients requiring lateral approach for insertion. The fibreoptic view of PLMA placement through the airway tube was graded on a scale from 4 (best view) to 1 (worst view).

GEB-guided PLMA insertion was more successful both after the first attempt (G 100%, I 69%, D 72%, P <0.01) and after two attempts (G 100%, I 78%, D 84%, P <0.05). Time taken for successful placement was significantly shorter in the GEB-guided group after two attempts (G 22∓2 seconds, I 31.9±18.8 seconds, D 29.5±18.6 seconds, P <0.05). The fibreoptic view through the airway tube was significantly better in the GEB-guided group (P <0.01). Incidence of trauma was significantly less in the GEB-guided group (P <0.05).
Perioperative Mortality Risk Score using Pre- and Post-operative Risk Factors in Older Patients
Authors: Story D. A. , Fink M. , Leslie K. , Myles P. S. , Yap S.-J. , Beavis V. , Kerridge R. K. , Mcnicol P. L.
Published: January 2019

We developed a risk score for 30-day postoperative mortality: the Perioperative Mortality risk score. We used a derivation cohort from a previous study of surgical patients aged 70 years or more at three large metropolitan teaching hospitals, using the significant risk factors for 30-day mortality from multivariate analysis. We summed the risk score for each of six factors creating an overall Perioperative Mortality score. We included 1012 patients and the 30-day mortality was 6%.

The three preoperative factors and risk scores were (“three A's”): 1) age, years: 70 to 79=1, 80 to 89=3, 90+=6; 2) ASA physical status: ASA I or II=0, ASA III=3, ASA IV=6, ASA V=15; and 3) preoperative albumin <30 g/l=2.5.

The three postoperative factors and risk scores were (“three I's”) 1) unplanned intensive care unit admission =4.0; 2) systemic inflammation =3; and 3) acute renal impairment=2.5. Scores and mortality were: <5=1%, 5 to 9.5=7% and ≥10=26%.

We also used a preliminary validation cohort of 256 patients from a regional hospital. The area under the receiver operating characteristic curve (C-statistic) for the derivation cohort was 0.80 (95% CI 0.74 to 0.86) similar to the validation C-statistic: 0.79 (95% CI 0.70 to 0.88), P=0.88. The Hosmer-Lemeshow test (P=0.35) indicated good calibration in the validation cohort. The Perioperative Mortality score is straightforward and may assist progressive risk assessment and management during the perioperative period. Risk associated with surgical complexity and urgency could be added to this baseline patient factor Perioperative Mortality score.
Fluconazole-induced Recurrent Ventricular Fibrillation Leading to Multiple Cardiac Arrests
Authors: Chakravarty C. , Singh P. M. , Trikha A. , Arora M. K.
Published: January 2019

This case report describes the successful management of a patient with diabetic ketoacidosis, who developed torsades de pointes leading to nine cardiac arrests secondary to intravenous fluconazole administration on a background of hypokalaemia and hypocalcaemia.
Effects of Propofol on Calcium Homeostasis in Human Skeletal Muscle
Authors: Migita T. , Mukaida K. , Hamada H. , Kobayashi M. , Nishino I. , Yuge O. , Kawamoto M.
Published: January 2019

Malignant hyperthermia is a pharmacogenetic skeletal muscle disorder of intracellular calcium (Ca2+) homeostasis with an autosomal dominant inheritance. The objective of this study was to investigate the safety of propofol by investigating its effects on calcium homeostasis and its effect sites in human skeletal muscles.

Muscle specimens were obtained from 10 individuals with predisposition to malignant hyperthermia. In skinned fibre experiments, we measured the effects of propofol on the Ca2+-induced Ca2+ release and the uptake of Ca2+ into the sarcoplasmic reticulum. Ca2+ imaging in primary myotubes was employed to analyse propofol-mediated alternations in the Ca2+ regulation and propofol-induced Ca2+ responses in the presence of Ca2+ channel blocker or Ca2+-induced Ca2+ release inhibitor.

Increased Ca2+ release from the sarcoplasmic reticulum and inhibition of Ca2+ uptake into the sarcoplasmic reticulum were not observed with 100 μM propofol. A rise of Ca2+ was not seen under 100 μM propofol and the EC50 value for propofol was 274.7±33.9 μM, which, is higher than the clinical levels for anaesthesia. Propofol-induced Ca2+ responses were remarkably attenuated in the presence of Ca2+ channel blocker or Ca2+-induced Ca2+ release inhibitor compared with the results obtained with caffeine.

We conclude firstly that propofol is safe for individuals with predisposition to malignant hyperthermia when it is used within the recommended clinical dosage range, and secondly that its mode of action upon ryanodine receptors is likely to be different from that of caffeine.
Intermittent Positive Airway Pressure to Manage Hypoxia during One-lung Anaesthesia
Authors: Russell W. J.
Published: January 2019

The effect of intermittent positive airway pressure to the non-ventilated lung was assessed in 10 patients who desaturated during one-lung ventilation. Once their saturation fell below 95% they were given a slow inflation of 2 l/min of oxygen into the non-ventilated lung for two seconds. This was repeated every 10 seconds for five minutes or until the saturation rose to 98%, whichever was sooner. The initial mean SpO2, was 89.3% ±4.2%. All 10 patients had an increase in saturation. The mean saturation following intermittent positive airway pressure was 96.5%±1.6% (P <0.0001). Similarly, the mean oxygen tension rose from 67.2∓12.8 mmHg to 98.9±19.8 mmHg.

Intermittent positive airway pressure should be considered for patients who desaturate while undergoing one-lung ventilation.
Point-of-Care Assessment of Antiplatelet Agents in the Perioperative Period: A Review
Authors: Gibbs N. M.
Published: January 2019

The aim of this paper was to review the strengths and limitations of current ‘point-of-care’ techniques for the detection of antiplatelet drug effects. The review was based on a Medline search for articles with key words related to “platelet function tests”, “point-of-care”, and “anaesthesia”, published in English between January 1996 and September 2008.

It was found that global assessments of ‘haemostasis’, such as the standard thrombelastograph®, Sonoclot®, Clot Signature Analyser® and Hemodyne™, are not specific for platelet function and are essentially insensitive to cyclooxygenase inhibitors (aspirin, non-steroidal anti-inflammatory drugs) and P2Y12 antagonists (ticlopidine, clopidogrel). Global assessments of ‘platelet function’, such as the PFA-100® and PlateletWorks®, are more specific for platelet function, but also have limited sensitivity for cyclooxygenase inhibitors and P2Y12 antagonists. The newer devices developed specifically for the assessment of antiplatelet drugs, such as Platelet Mapping, the Impact™ Cone and Platelet Analyser and the VerifyNow®, are more promising, but are not as sensitive as laboratory platelet aggregometry. All three categories of devices detect GpIIb/IIIa antagonists (abciximab, tirofiban, eptfibatide) activity, but not all provide quantitative assessments for monitoring therapy.

The limitations appeared to be related to the complexity of platelet function, the multiple pathways of platelet activation, the wide interpatient variability in platelet responses and the interdependence between platelets and other aspects of coagulation.

The strengths and limitations of point-of-care devices should be appreciated before they are used to assist clinical decision-making in the perioperative period.
Risk Factors and Outcomes of Methicillin-resistant Staphylococcus Aureus Bacteraemia in Critically Ill Patients: A Case Control Study
Authors: Ho K. M. , Robinson J. O.
Published: January 2019

Methicillin-resistant Staphylococcus aureus (MRSA) infection is an increasing threat to critically ill patients in many intensive care units. MRSA bacteraemia is an extreme form of MRSA infection and is a significant cause of morbidity and mortality. This case control study aimed to assess the risk factors and outcomes of MRSA bacteraemia compared to methicillin-susceptible Staphylococcus aureus (MSSA) bacteraemia. A total of 21 MRSA bacteraemia and 60 randomly selected MSSA bacteraemia episodes, admitted to the intensive care unit at Royal Perth Hospital between 1997 and 2007, were considered. There was a suggestion that hospitalisation within the preceding six months (P=0.087) and residence in a long-term care facility (P=0.065) were associated with a higher risk of MRSA bacteraemia. MRSA bacteraemia was more often treated with antibiotics to which the pathogen was not susceptible in vitro (38.1% vs 0%, P=0.001), resulting in a longer duration of fever (median 7.0 vs 2.0 days, P=0.009) and bacteraemia (mean 3.2 vs 0.6 days, P=0.005) and a higher incidence of metastatic seeding of infection (52.4% vs 21.7%, P=0.012) as compared to MSSA bacteraemia. While in-hospital mortality between MRSA and MSSA was similarly high (47.6% vs 38.3% for MRSA and MSSA respectively, P=0.607), a significant proportion of the patients who had MRSA bacteraemia died within five years of hospital discharge (36.4%, hazard ratio 26.0, 95% confidence interval 1.90 to 356.7, P=0.015). Infections contributed to 75% of the deaths after hospital discharge in patients who had an episode of MRSA bacteraemia. MRSA bacteraemia carries a much worse long-term prognosis than MSSA bacteraemia and that could be explained by recurrent MRSA infections and residual confounding.
The Ethics of Anaesthesia Learning Curves
Authors: White S. M.
Published: January 2019

While the concept of the ‘learning curve’ is widely accepted and understood in medical education, the ethical appreciation of what this involves for patients has been under-represented in medical journals. Advances in medical technology have produced an armoury of diagnostic and therapeutic invasive procedures, which must be perfected by anaesthetists for the benefit of patients. Anaesthetic training involves practice using patients, which potentially exposes patients to excess procedural risk. However, such risk can be minimised through close supervision of trainees and the development of non-patient training aids. Most importantly, for training to be ethical, it must involve the patient: it is for patients to decide whether they consent to taking part in training and their consent should always be sought where possible.
Postoperative Analgesia and Respiratory Events in Patients with Symptoms of Obstructive Sleep Apnoea
Authors: Blake D. W. , Yew C. Y. , Donnan G. B. , Williams D. L.
Published: January 2019

Symptoms of obstructive sleep apnoea are common in patients presenting for surgery and are associated with increased morbidity. Analgesia contributes significantly to postoperative respiratory depression and obstruction, so we compared standard morphine patient-controlled analgesia with an opioid-sparing protocol (tramadol patient-controlled analgesia, parecoxib and rescue-only morphine) in these patients. Sixty-two patients presenting for elective surgery with body mass index ≥28 and signs or symptoms suggesting obstructive sleep apnoea were randomised to receive either the opioid or opioid-sparing postoperative analgesia protocol, with continuous respiratory monitoring for 12 hours on the first postoperative night. The number of respiratory events (apnoeas and hypopnoeas) and oxygen desaturations were compared. There was no difference between treatment groups in the number of obstructive apnoeas, hypopnoeas or central apnoeas. However, central apnoeas and a rate of respiratory events >15 per hour were related to postoperative morphine dose (P=0.005 and P=0.002). In patients at risk of obstructed breathing, intention to treat with an opioid-sparing analgesia protocol did not decrease the rate of respiratory events, although the rate was still related to the total morphine dose.
Comparison between the Effects of Propofol and Etomidate on Motor and Electroencephalogram Seizure Duration during Electroconvulsive Therapy
Authors: Tan H. L. , Lee C. Y.
Published: January 2019

An ideal anaesthetic for electroconvulsive therapy (ECT) should have rapid onset and offset with no effect on seizure duration, and provide cardiovascular stability during the procedure. Propofol is commonly used, even though it has been shown to shorten seizure duration which might affect the efficacy of ECT. Etomidate has been advocated as an alternative. This prospective, randomised, single-blind, crossover study was conducted to compare the effects of etomidate (Etomidate-®Lipuro, B. Braun Ltd, Melsungen, Germany) and propofol (Diprivan®, AstraZeneca, UK) on seizure duration as well as haemodynamic parameters in patients undergoing ECT. Twenty patients aged between 18 and 70 years were recruited. Group I received etomidate 0.3 mg/kg for the first course of ECT (Group IA) and propofol 1.5 mg/kg for the second ECT (Group IB), while Group II received propofol for the first ECT (Group IIA) and etomidate for the second ECT (Group IIB). There was a washout period of two to three days in between procedures. Parameters recorded included motor seizure duration, electroencephalogram seizure duration, blood pressure and heart rate. Analysis demonstrated neither period effect nor treatment period interaction. Etomidate was associated with a significantly longer motor and electroencephalogram seizure duration compared with propofol (P <0.01). Neither drug demonstrated consistent effects in suppressing the rise in heart rate or blood pressure during ECT. Myoclonus and pain on injection were the most common adverse effects in etomidate group and propofol group respectively. Etomidate is a useful anaesthetic agent for ECT and should be considered in patients with inadequate seizure duration with propofol.
Mortality and Cost Outcomes of Elderly Trauma Patients Admitted to Intensive Care and the General Wards of an Australian Tertiary Referral Hospital
Authors: Chan L. Y. L. , Moran J. L. , Clarke C. , Martin J. , Solomon P. J.
Published: January 2019

Mortality and cost outcomes of elderly intensive care unit (ICU) trauma patients were characterised in a retrospective cohort study from an Australian tertiary ICU. Trauma patients admitted between January 2000 and December 2005 were grouped into three major age categories: aged ≥65 years admitted into ICU (n=272); aged ≥65 years admitted into general ward (n=610) and aged <65 years admitted into ICU (n = 1617). Hospital mortality predictors were characterised as odds ratios (OR) using logistic regression. The impact of predictor variables on (log) total hospital-stay costs was determined using least squares regression. An alternate treatment-effects regression model estimated the mortality cost-effect as an endogenous variable. Mortality predictors (P ≤0.0001, comparator: ICU ≥65 years, ventilated) were: ICU <65 not-ventilated (OR 0.014); ICU <65 ventilated (OR 0.090); ICU age ≥65 not-ventilated (OR 0.061) and ward ≥65 (OR 0.086); increasing injury severity score and increased Charlson comorbidity index of 1 and 2, compared with zero (OR 2.21 [1.40 to 3.48] and OR 2.57 [1.45 to 4.55]). The raw mean daily ICU and hospital costs in A$ 2005 (US$) for age <65 and ≥65 to ICU, and ≥65 to the ward were; for year 2000: ICU, $2717 (1462) and $2777 (1494); hospital, $1837 (988) and $1590 (855); ward $933 (502); for year 2005: ICU, $3202 (2393) and $3086 (2307); hospital, $1938 (1449) and $1914 (1431); ward $1180 (882). Cost increments were predicted by age ≥65 and ICU admission, increasing injury severity score, mechanical ventilation, Charlson comorbidity index increments and hospital survival. Mortality cost-effect was estimated at −63% by least squares regression and −82% by treatment-effects regression model. Patient demographic factors, injury severity and its consequences predict both cost and survival in trauma. The cost mortality effect was biased upwards by conventional least squares regression estimation.
Ambulatory Continuous Femoral Analgesia for Major Knee Surgery: A Randomised Study of Ultrasound-Guided Femoral Catheter Placement
Authors: Fredrickson M. J. , Danesh-Clough T. K.
Published: January 2019

Needle-nerve stimulation has a false negative motor response rate, which may increase needle passes. This prospective, randomised study tested the hypothesis that femoral nerve catheters placed with ultrasound-only guidance could provide comparable postoperative analgesia to those placed using a conventional nerve stimulation endpoint. Patients presenting for major knee surgery to the lead investigator were recruited. Needles introduced for femoral nerve catheter placement were initially guided with ‘oblique’ out-of-plane ultrasound imaging but were then prospectively randomised to either an ultrasound (n=21) or nerve stimulation (n=24) endpoint. An elastomeric infusion of ropivacaine 0.2% 2 ml/hour with as required hourly 5 ml boluses was continued for >48 hours in hospital and/or in the home. Needle time under the skin and numerical rating pain score during insertion were recorded. Patients were questioned for worst numerical rating pain score, the need for supplementary ropivacaine boluses and tramadol on postoperative days one and two. There was no difference in the worst numerical rating pain score at rest and on movement and the requirement for supplementary ropivacaine boluses or tramadol during the first 48 postoperative hours. The median (quartiles) needle time under the skin was 58 seconds (51 to 76) in the ultrasound group and 120 seconds (95 to 178) in the nerve stimulation group (P=0.001). The median (quartiles) insertion numerical rating pain score was 2 (0 to 2) in the ultrasound group and 4 (2 to 6) in the nerve stimulation group (P=0.014). Femoral nerve catheters placed for major knee surgery using an ultrasound endpoint provided postoperative analgesia comparable to that obtained when using a nerve stimulation endpoint and were associated with a reduction in both needle manipulations and procedure-related pain.
An Intraoperative Pre-incision Single Dose of Intravenous Ketamine does not have an Effect on Postoperative Analgesic Requirements under Clinical Conditions
Authors: Dullenkopf A. , Müller R. , Dillmann F. , Wiedemeier P. , Hegi T. R. , Gautschi S.
Published: January 2019

Evidence about the effectiveness of the N-methyl-D-aspartate antagonist ketamine to reduce postoperative acute and long-lasting pain is inconclusive. The aim of this study was to investigate effects of adding an intraoperative, pre-incision single intravenous dose of ketamine to a routine anaesthesia regimen on postoperative analgesic requirements, side-effects and persisting pain up to three months.

After obtaining Ethical Committee approval and written informed patient consent, 120 patients were included in this prospective, randomised, double-blinded, placebo-controlled study. Patients were randomised into three groups, receiving 0.15 mg/kg ketamine intravenously, 0.5 mg/kg ketamine intravenously or normal saline in groups low-dose ketamine, moderate-dose ketamine and placebo, respectively. Anaesthesia maintenance, intraoperative pain management and postoperative pain therapy were standardised. The primary study endpoint was consumption of morphine during the first 24 hours after surgery. Three months after surgery, pain scores were assessed. Data were compared by t-test and Kruskall-Wallis test with alpha = 0.05.

There was no difference between the groups in the assessed variables.

These findings indicate that with the anaesthesia regimen described, and in the doses used, a single intravenous dose of ketamine does not reduce postoperative analgesic requirement or postoperative pain at three months.
Ruptured Hydatid Cyst Masquerading as Tension Penumothorax
Authors: Chacko J. , Rao S. , Basawaraj K. , Chatterjee S.
Published: January 2019

We report a 35-year-old man who presented to us with features suggestive of a tension pneumothorax. However, insertion of a chest tube did not result in any signs of improvement. Further investigation demonstrated that he had a ruptured hydatid cyst. He underwent an emergency thoractomy and excision of the cyst. Ruptured hydatid cyst should be considered as a possibility in patients who present with sudden onset respiratory distress and hypoxia in geographical areas where the disease may be prevalent.
Audit of Performance of Size 1.5 ProSeal Laryngeal Mask Airways in Infants Less than Six Months Undergoing Inguinal Herniotomy
Authors: White M. C. , Kelly F. , Bayley G. , Sale S. , Cook T. , Stoddart P. A.
Published: January 2019

Many anaesthetists have found the size 1.5 classic Laryngeal Mask Airway unsuitable for use in children under 10 kg, whereas recent studies evaluating the ProSeal Laryngeal Mask Airway (PLMA) show high success rates, even during laparoscopic surgery. Our routine practice has been to use tracheal intubation for inguinal herniotomy in children weighing less than 10 kg. Following the introduction of the PLMA to our hospital, we decided to audit our use of the PLMA 1.5 in this group of patients.

We included 20 consecutive infants, aged less than six months and weighing 5 to 10 kg. We recorded patient, anaesthetic and insertion details, device performance data and complications. No aspect of anaesthetic practice was changed by involvement in this audit.

The PLMA was inserted successfully at the first attempt in 85% (17/20) of infants. Overall successful insertion occurred in 90% (18/20) and satisfactory airway maintenance was provided for the duration of anaesthesia in 90% (18/20). The mean leak pressure was 24 cmH20) (range 15 to 30 cmH20).

We found the 1.5 PLMA provided a satisfactory airway in 90% of infants. This report adds to the evidence that the PLMA 1.5 can provide a satisfactory alternative to intubation in selected infants.
The Rise of Simulation in Technical Skills Teaching and the Implications for Training Novices in Anaesthesia
Authors: Castanelli D. J.
Published: January 2019

Changes in work practices have led to a decline in the opportunities for anaesthetic trainees to learn technical procedures in supervised practice. Efforts to mitigate medical error and other changes have coincided with the development of alternative training methods so that it is increasingly difficult to justify the traditional model of teaching technical procedures.

The range of simulators available for training in technical procedures in anaesthesia continues to expand. While simulation has been widely adopted in anaesthesia for crisis management training, there is little documented evidence of its use for technical skills training.

The theoretical basis for the use of simulation to aid the acquisition of psychomotor skills and the development of expertise is now well established. In addition, practical frameworks that allow this theory to be applied in a systematic fashion have been developed and successfully used in other specialties.

Using the available simulation equipment and educational tools, trainees can be prepared to begin supervised practice having demonstrated adequate procedural knowledge and expertise in simulation. With the use of simulated patients there is also the opportunity to integrate non-technical skills as well where appropriate.

This review summarises the justification for the use of simulation in technical skills training in anaesthesia and the educational theory that supports its use, and outlines one of the available frameworks that can be used to aid its application.
Continuous Intra-articular Infusion of Ropivacaine after Unilateral Total Knee Arthroplasty
Authors: Reeves M. , Skinner M. W.
Published: January 2019

Intra-articular infusion of local anaesthetic after joint arthroplasty is attractive in that it is simple and will not cause motor block. However, the efficacy of the technique has yet to be established. We enrolled 66 patients scheduled for unilateral total knee arthroplasty under general anaesthesia and single-shot femoral and sciatic nerve blocks. All patients had an intra-articular Painbuster® device sited at the end of the procedure. Patients were then randomised to control or one of two treatment arms – low-dose and high-dose ropivacaine. In the control group the balloon was filled with saline, in the low-dose group with 0.2% ropivacaine and in the high-dose group 0.375% ropivacaine. The catheters were infused continuously for 48 hours and then removed. Patients were followed up daily for three days to determine pain scores, opioid consumption and subjective assessment of the analgesic efficacy of the catheter. Data were analysed for 30 controls and 31 in the treatment arms. Both groups were similar. There were no significant differences between the control and treatment groups at all time points after adjustment for age. Patients in the high-dose group had higher pain scores and higher opioid consumption than the control groups from 24 to 48 hours. There were two cases of infection, both in the treatment groups.

No positive benefit of intra-articular infusion of local anaesthetic after total knee arthroplasty could be identified. On the contrary there may be negative effects in terms of expense, pain and possibly infection risks.
Derivation and Prospective Testing of a Two-step Sevoflurane-O2-N2O Low Fresh Gas Flow Sequence
Authors: Van Zundert T. , Brebels A. , Hendrickx J. , Carette R. , De Cooman S. , Gatt S. , De Wolf A.
Published: January 2019

Simple vaporiser setting (FD) and fresh gas flow (FGF) sequences make the practice of low-flow anaesthesia not only possible but also easy to achieve. We sought to derive a sevoflurane FD sequence that maintains the end-expired sevoflurane concentration (FAsevo) at 1.3% using the fewest possible number of FD adjustments with a previously described O2-N2O FGF sequence that allows early FGF reduction to 0.7 l.min−1.

In 18 ASA physical status I to II patients, FD was determined to maintain FAsevo at 1.3% with 2 l.min−1 O2 and 4 l.min−1 N2O FGF for three minutes, and with 0.3 and 0.4 l.min−1 thereafter. Using the same FGF sequence, the FD schedule that approached the 1.3% FAsevo pattern with the fewest possible adjustments was prospectively tested in another 18 patients.

The following FD sequence approximated the FD course well: 2% from zero to three minutes, 2.6% from three to 15 minutes and 2.0% after 15 minutes. When prospectively tested, median (25th; 75th percentile) performance error was 0.8 (-2.9; 5.9)%, absolute performance error 6.7 (3.3; 10.6)%, divergence 18.2 (-5.6; 27.4)%.h−1 and wobble 4.4 (1.7; 8.1)%. In one patient, FGF had to be temporarily increased for four minutes.

One O2/N2O rotameter FGF setting change from 6 to 0.7 l.min−1 at three minutes and two sevoflurane FD changes at three and 15 minutes maintained predictable anaesthetic gas concentrations during the first 45 minutes in all but one patient in our study.
Predictors and Outcome Associated with an Enterococcus Positive Isolate during Intensive Care Unit Admission
Authors: Chatterjee I. , Duthunty J. M. , Iredell J. , Gallagher J. E. , Sud A. , Woods M. , Lipman J.
Published: January 2019

This study reports the incidence, risk factors and mortality associated with a positive Enterococcus spp. isolate during admission to two tertiary intensive care units participating in an antibiotic cycling study. Incidence was low, with only 4.2% of admissions (36/852) at Royal Brisbane and Women's Hospital and 2.8% (31/1104) at Westmead Hospital developing a positive Enterococcus spp. isolate (P=0.087). A positive enterococcal isolate, while not an independent predictor of mortality (odds ratio [OR] = 1.6, 95% confidence internal [CI] 0.80 to 3.2, P=0.18), may be a marker of the underlying severity of illness with higher unadjusted in-hospital mortality (26% or 17/66 vs 14% or 250/1855, P=0.007). Independent risk factors for a positive isolate were use of meropenem/imipenem (OR=5.7, 95% CI 2.4 to 14, P <0.001) and cefepime (OR=2.5, 95% CI 1.2 to 5.3, P=0.017) within 48 hours of intensive care unit admission, the presence of a nasogastric tube (OR=4.1, 95% CI 1.3 to 14, P=0.018), renal replacement therapy (OR=2.2, 95% CI 1.0 to 4.7, P=0.046), operative intervention (OR=1.8, 95% CI 1.0 to 3.2, P=0.035) and age (OR=1.2, 95% CI 1.1 to 1.5, P=0.009). None of these factors, except for the need for renal replacement therapy (OR=6.2, 95% CI 1.4 to 27, P=0.015), was associated with increased mortality. Enterococci-directed empiric therapy in the treatment of sepsis remains of unproven value, although this negative finding must be evaluated against other higher powered studies.
An Assessment of the Population Variance of the Strong Ion Gap using Monte Carlo Simulation
Authors: Anstey C. M.
Published: January 2019

The strong ion gap is a derived parameter used to quantify clinically significant but unmeasured charged species in human plasma. In the general population the strong ion gap has a mean value of approximately 0.0 mEq/l, but at present no reference range exists. This severely limits its clinical application. In order to establish a reference range, a 95% confidence interval around the population mean must be calculated. As each of the variables that make up the strong ion gap have their own unique and different means and standard deviations, simple methods of pooled variance can not be used to calculate this internal. In place of a direct solution, Monte Carlo methodology was employed using known reference standard deviations to construct a large sample of a simulated population. In addition, the partial correlation between the plasma concentrations of sodium and chloride was included in the calculations. Sample sets of 20,000 were simulated, each giving a normally distributed strong ion gap. A 95% confidence interval of 3.9±6.4 mEq/l was derived. Depending on the degree of strong ion correlation, minima and maxima for this reference range were calculated as 3.9±5.1 mEq/l and 3.9±7.6 mEq/l respectively. Reasons for the positive bias in the mean strong ion gap result are examined briefly.
Comparison of Forehead Max-Fast Pulse Oximetry Sensor with Finger Sensor at High Positive End-expiratory Pressure in Adult Patients with Acute Respiratory Distress Syndrome
Authors: Hodgson C. L. , Tuxen D. V. , Holland A. E. , Keating J. L.
Published: January 2019

In the critical care setting it may be difficult to determine an accurate reading of oxygen saturation from digital sensors as a result of poor peripheral perfusion. Limited evidence suggests that forehead sensors may be more accurate in these patients. We prospectively compared the accuracy of a forehead reflectance sensor (Max-Fast) with a conventional digital sensor in patients with acute respiratory distress syndrome during a high positive end-expiratory pressure (PEEP) recruitment manoeuvre (stepwise recruitment manoeuvre).

Sixteen patients with early acute respiratory distress syndrome were enrolled to evaluate the blood oxygen saturation during a stepwise recruitment manoeuvre. PEEP was increased from baseline (range 10 to 18) to 40 cmH2O, then decreased to an optimal level determined by individual titration. Forehead and digital oxygen saturation and arterial blood gases were measured simultaneously before, during and after the stepwise recruitment manoeuvre at five time points.

Seventy-three samples were included for analysis from 16 patients. The SaO2 values ranged from 73 to 99.6%. The forehead sensor provided measurements that deviated more from arterial measures than the finger sensor (mean absolute deviations 3.4%, 1.1% respectively, P=0.02). The greater variability in forehead measures taken at maximum PEEP was reflected in the unusually large precision estimates of 4.24% associated with these measures. No absolute differences from arterial measures taken at any other time points were significantly different.

The finger sensor is as accurate as the forehead sensor in detecting changes in arterial oxygen saturation in adults with acute respiratory distress syndrome and it may be better at levels of high PEEP, such as during recruitment manoeuvres.
The Efficacy of Landiolol for Suppressing the Hyperdynamic Response following Laryngoscopy and Tracheal Intubation: A Systematic Review
Authors: Inoue S. , Tanaka Y. , Kawaguchi M. , Furuya H.
Published: January 2019

Landiolol is a recently developed, selective short-acting β1-antagonist. The aim of the study was to evaluate the efficacy of landiolol for suppressing haemodynamic changes induced by laryngoscopy and tracheal intubation (LTI) in Japanese patients.

A comprehensive search was undertaken to identify all randomised comparisons of landiolol with placebo that examined effects on haemodynamic responses following LTI. MEDLINE, Cochrane CENTRAL, EMBASE and the Japanese Central Review of Medicine were searched from their date of inception to February 2009. Trials were included in the review if heart rate, systolic blood pressure or mean blood pressure was recorded at three different stages: pre-induction, just before intubation and in the post-intubation period. Weighted mean differences and 95% confidence intervals (CI) were calculated for changes in haemodynamic variables between treatment and placebo groups.

Seven randomised controlled trials involving 325 patients were included in the study. Of these, five trials that used the same continuous infusion regimen for landiolol (0.125 mg/kg/minute for one minute followed by 0.04 mg/kg/minute) showed efficacy in attenuation of heart rate and blood pressure following LTI (heart rate weighted mean difference: −21.18 bpm, 95% CI −18.59 to −14.20; systolic blood pressure weighted mean difference: −23.03 mmHg, 95% CI −43.59 to −2.47; mean blood pressure weighted mean difference: −16.26 mmHg, 95% CI −23.96 to −8.55). The other two studies used bolus administration of landiolol (0.1 to 0.3 mg/kg), but it was difficult to evaluate the efficacy because of the limited amount of data.

Landiolol administration at 0.125 mg/kg/minute for one minute followed by 0.04 mg/kg/minute effectively suppresses the increases in heart rate and blood pressure following LTI. For a bolus regimen of landiolol, further studies are required to determine the efficacy and the optimal dose and timing for suppression of haemodynamic responses following LTI.
Gilles vs Pugh and the lost letter
Authors: Paull J.D.
Published: January 2019

In June 1842 the wife of Lewis W. Gilles, a banker in Launceston, wrote to Mrs Pugh, inviting her and her husband, Mr William Russ Pugh, to an entertainment and ball. The Pughs neither responded to the invitation, nor attended the ball. Mrs Gilles mentioned the discourtesy of their non-attendance to a friend, who the following morning brought the complaint to the attention of Dr Pugh. Pugh immediately wrote a brief note explaining that neither he nor his wife had received the invitation. Further correspondence between Gilles and Pugh ensued, becoming more and more bitter until Pugh publicly insulted Gilles. The Launceston Club, of which both men were members, ultimately became a casualty of the dispute and was dissolved. A Supreme Court defamation and libel case followed with Gilles as plaintiff and Pugh as defendant. Gilles won the case but received only token damages.

And the missing letter? Too late, Mrs Pugh's maid found it tucked between the pages of a periodical on the dresser.
Rapid Reversal of Coagulopathy in Warfarin-Related Intracranial Haemorrhages with Prothrombin Complex Concentrates
Authors: Chong C. T. , Lew T. W. K. , Kuperan P. , Tan J. J. E. , Tan H. L. , Kwek T. K.
Published: January 2019

We report our initial experience using Profilnine SD, a 3-Factor prothrombin complex concentrate (PCC) in combination with fresh frozen plasma and vitamin K in seven patients admitted to our neurointensive care unit with oral anticoagulation therapy-related intracranial haemorrhage over a six-month period, to achieve rapid normalisation of the international normalised ratio (INR) and allow surgical evacuation when indicated.

Four patients presented with subdural haematomas while three had intracerebral haematomas. Six of seven patients had admission INR in the appropriate therapeutic range for oral anticoagulation therapy. The median dose of PCC administered was 28.5 IU/kg body weight (interquartile range 21.3 to 38.5 IU/kg). All four patients with subdural haematoma underwent surgical evacuation once INR was less than 1.5. Median time from computed tomography diagnosis to surgery was 275 minutes (range 102 to 420 minutes). The median time to INR normalisation post-PCC administration was shorter, at 85 minutes (range 50 to 420 minutes) for the four patients who survived, versus 10 hours (range 9 to 44 hours) in the three patients who died. Two of the three patients who died had haematoma increase, worsening midline shift and subfalcine herniation, leading to withdrawal of therapy.

Prothrombin complex concentrates should be considered for use in the urgent reversal of INR in oral anticoagulation therapy-related intracranial haemorrhage, potentially halting haematoma expansion and expediting urgent neurosurgical intervention, although data from randomised controlled trials is still lacking. The literature supporting the use of PCC is reviewed and a protocolised emergent treatment algorithm is proposed, which may help achieve earlier consistent normalisation of the INR.
The Development and Implementation of an Obstetric Cell Salvage Service
Authors: McDonnell N. J. , Kennedy D. , Long L. J. , Gallagher-Swann M. C. , Paech M. J.
Published: January 2019

Cell salvage in obstetric haemorrhage is now endorsed by a number of organisations. Most of the literature has focused on isolated case series and safety. We describe how cell salvage, including a quality assurance process conducted prior to clinical implementation, was introduced to our stand-alone obstetric hospital which had no previous experience of this technique.

An implementation committee was established and 25 quality assurance and familiarisation cases were initially conducted. As part of this process the alpha fetoprotein, haematocrit, free plasma haemoglobin, potassium and Kleihauer tests were performed when enough blood was available for processing. Our guidelines for clinical use included women at greatly increased risk of obstetric haemorrhage and women at increased risk of haemorrhage who refused traditional transfusion. After the successful completion of this process, cell salvage was signed off for clinical use in March 2007 and was used on 51 occasions between March 2007 and July 2009. Twenty-one patients had salvaged blood re-transfused and for seven patients this was their only red blood cell replacement. The median blood loss in patients re-transfused was 3000 ml (range <500 to 8500 ml), with the median volume re-transfused 359 ml (range 60 to 1300 ml). There was one episode of unexplained hypotension associated with administration of salvaged blood.

We have successfully introduced obstetric cell salvage into clinical practice. A quality assurance process prior to implementation was beneficial for the staff involved. Despite targeting a high-risk obstetric population, our re-transfusion rates are approximately 40%. No serious adverse events have been recorded. We recommend that in units that already provide intraoperative cell salvage in a non-obstetric setting, extending the service into obstetric situations should be considered. Units that routinely care for high-risk obstetric patients should also consider the introduction of such a service. Post transfusion Kleihauer testing should be performed as soon as possible in Rhesus-negative mothers who deliver a Rhesus-positive foetus, so that appropriate anti-D prophylaxis can be administered.
Intrahospital Transfer of Critically Ill Patients; a Prospective Audit within Flinders Medical Centre
Authors: Winter M. W.
Published: January 2019

A prospective observational audit of 32 intrahospital transfers of critically ill patients was undertaken within Flinders Medical Centre. The aim was to assess the adherence of recommended staffing and equipment required during intrahospital transfer according to the “Minimum standards for intrahospital transport of critically ill patients” (PS39) published in 2003 by the Joint Faculty of Intensive Care Medicine, the Australian and New Zealand College of Anaesthetists and Australasian College for Emergency Medicine. Incident monitoring was also performed during the audit. Findings showed adequate staffing for 75% of the transfers observed. Oxygen saturation and blood pressure monitoring were present in 97%, heart rate monitoring in 90.5%, electrocardiogram monitoring in 84.5% and capnometry monitoring in 75% of the intrahospital transfers observed. Overall, 44% of transfers resulted in incident occurrence, many of which were preventable with careful planning and increased communication between staff. Intensive care units are encouraged to continually evaluate their intrahospital transportation of critically ill patients and to identify system problems contributing to failure of adherence to the current guidelines.
Leukocytotic Pseudohypoxaemia
Authors: Ben-Meir M. , Tibballs J.
Published: January 2019

A case of hypoxaemia was concluded to be a pseudo-condition after investigation demonstrated that the hypoxaemia was not related to lung disease, but rather to the time expiring between obtaining and analysing blood samples and to a reduction in the magnitude of the patient's white cell count.
Status Asthmaticus Complicated by Cardiac Arrest
Authors: McIver L. J. , Halkidis L. , Talbutt P.
Published: January 2019

In the setting of severe acute asthma, electrocardiographic abnormalities are not uncommon and some patients will develop reversible systolic dysfunction. However, acute myocardial infarction and potentially fatal arrhythmias are rare. We report the case of a middle-aged indigenous male who suffered an ST-elevation myocardial infarction and then pulseless ventricular tachycardia arrest while still in the acute phase of treatment for status asthmaticus.
Cardiovascular Ultrasound in Detecting Central venous Catheter Thrombosis in the Intensive Care Unit: Splenectomy and Antiphospholipid Syndrome
Authors: Saranteas T. , Poularas J. , Mandila C. , Kostopanagiotou G. G. , Karabinis A.
Published: January 2019

Venous thrombosis of the upper extremities is becoming increasingly prevalent in the intensive care unit as a result of chronic in-dwelling central venous catheters. We report two rare cases in which combined transoesophageal echocardiography and vascular ultrasound examination aided in the identification of catheter-related thrombosis in two patients suffering from splenectomy-induced thrombocytosis and antiphospholipid syndrome respectively.