bluuebunny/crossref_metadata_2025 huggingface dataset:
How Well do Serum sTREM-1 Measurements Prognosticate in Septic Shock?
Authors: Phua J. , Koay E. S. C. , Zhang D. , Lee K. H.
Published: January 2019

The soluble triggering receptor expressed on myeloid cells (sTREM)-1 has emerged as a potentially useful biomarker for the diagnosis of sepsis. This study aimed to evaluate the prognostic utility of serum sTREM-1 in septic shock, in comparison with that of procalcitonin measurements. Thirty-one consecutive patients in a tertiary medical intensive care unit with septic shock were studied. sTREM-1 levels in blood were measured using a modified immunoblot array technique on days one to three of intensive care unit admission. Serum procalcitonin and interleukin (IL)-1β, IL-6, IL-10 and tumour necrosis factor-a levels were also measured. No significant difference was observed in the sTREM-1 levels on the first three days between survivors and nonsurvivors. sTREM-1 levels moderately correlated with the Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores on day three, but did not correlate with vasopressor requirements, cytokine levels and the presence of bacteraemia. In contrast, procalcitonin levels were significantly higher in nonsurvivors than in survivors on days two and three. A significant relationship also existed between procalcitonin levels and the other variables. In conclusion, this study found that the prognostic utility of serum sTREM-1 in septic shock is poor and that procalcitonin measurements perform better in this regard.
Antimicrobial Effects of Two Anaesthetic Agents: Dexmedetomidine and Midazolam
Authors: Ayoglu H. , Kulah C. , Turan I.
Published: January 2019

Some anaesthetic agents are known to inhibit microbial growth. The aim of this in vitro study was to investigate possible antimicrobial effects of two frequently used agents in intensive care units, dexmedetomidine and midazolam.

Antimicrobial effect was tested on Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa by broth microdilution method.

Midazolam showed inhibitor and bactericidal effect on S. aureus at concentrations 256 μg.ml -1 and 512 μgml -1 respectively and on E. faecalis at concentrations 128 μg.ml 1 and 256 μg.ml -1. Dexmedetomidine demonstrated inhibitor effect on S. aureus, E. coli and P. aeruginosa at concentrations 32 μg.ml -1, 16 μg.ml -1 and 16 μg.ml -1 respectively.

Midazolam had inhibitor and bactericidal effects on S. aureus and E. faecalis. Dexmedetomidine had only inhibitor effects on S. aureus, E. coli and P. aeruginosa. Further studies are needed to determine the antimicrobial mechanisms and clinical applications.
Transient Transmural Ischaemia during Endobronchial Laser Treatment: Possible Coronary Artery Embolism
Authors: Haydon T. P. , Claydon R. , Hall A.
Published: January 2019

We report the case of a 51-year-old woman receiving endobronchial treatment with neodymium.yttrium garnet laser. After 30 minutes of stable anaesthesia and laser treatment, sudden inferior myocardial ischaemia developed followed by haemodynamic collapse. Resuscitation with fluids, pressors, atropine and esmolol was successful, leading to rapid resolution of the ischaemia and full recovery. The sudden onset and time course of the ST segment elevation was consistent with coronary artery air embolism, as occurs occasionally during cardiac surgery. Systemic gas embolism during endobronchial laser treatment has been previously reported with poor outcomes and significant mortality. This complication can be avoided with awareness of the mechanism while appropriate monitoring may allow early detection and successful treatment.
Acute Myocarditis Mimicking Lateral Myocardial Infarction
Authors: Mottard N. , Mewton N. , Bonnefoy E. , Abdellaoui M. , Revel D. , Kirkorian G.
Published: January 2019

We report a case of myocarditis mimicking acute lateral myocardial infarction and treated as such initially, which was complicated by ventricular fibrillation a few hours after admission to the intensive care unit. The correct diagnosis was rapidly made using a low-dose delayed-enhanced cardiac multidetector computed tomography scan performed immediately after a normal coronary angiogram, demonstrating typical myocardial late hyperenhancement and good correlation with delayed enhanced magnetic resonance imaging. This case suggests that myocarditis can be accurately diagnosed by delayed-enhanced cardiac multidetector computed tomography in an emergency setting. The other lesson from this case is that patients presenting with severe clinical symptoms, important ECG signs and high myocardial enzyme levels should be closely monitored for at least 72 hours, even when myocardial infarction has been excluded.
Comparison between Sevoflurane/Remifentanil and Propofol/Remifentanil Anaesthesia in Providing Conditions for Somatosensory Evoked Potential Monitoring during Scoliosis Corrective Surgery
Authors: Fung N. Y. , Hu Y. , Irwin M. G. , Chow B. F. M. , Yuen M. Y.
Published: January 2019

Somatosensory evoked potential (SSEP) monitoring is an important tool in spinal corrective surgery. Anaesthesia has a significant influence on SSEP monitoring and a technique which has the least and shortest suppressant effect on SSEP while facilitating a fast recovery from anaesthesia is ideal. We compared the effect of sevoflurane/remifentanil and propofol/remifentanil anaesthesia on SSEPs during scoliosis corrective surgery and assessed patients’ clinical recovery profiles.

Twenty patients with idiopathic scoliosis receiving surgical correction with intraoperative SSEP monitoring were prospectively randomised to receive sevoflurane/remifentanil anaesthesia or propofol/remifentanil anaesthesia. During surgery, changes in anaesthesia dose and physiological variables were recorded, while SSEP was continuously monitored. A simulated ‘wake-up’ test was performed postoperatively to assess speed and quality of recovery from anaesthesia.

The effects of propofol and sevoflurane resulted in SSEP amplitude variability between 18.0% ± 3.5% to 28.7% ± 5.9% and SSEP latency variability within 1.3% ± 0.4% to 2.6% ± 1.2%. Patients receiving sevoflurane had faster suppression and faster recovery of SSEP amplitude compared to propofol (P <0.05), although propofol anaesthesia showed less within-patient variability in Cz amplitude and latency (P <0.05). On cessation of anaesthesia, time to eye-opening (5.2 vs. 16.5 minutes) and toe movement (5.4 vs. 17.4 minutes) was shorter following sevoflurane (all P <0.05).

These findings indicate that propofol produces a better SSEP signal than sevoflurane. However, adjustments in sevoflurane concentration result in faster changes in the SSEP signal than propofol. Assessment of neurological function was facilitated more rapidly after sevoflurane anaesthesia.
Effect of Recruitment and Body Positioning on Lung Volume and Oxygenation in Acute Lung Injury Model
Authors: Ryu H. G. , Bahk J.-H. , Lee H.-J. , Im J.-G.
Published: January 2019

The mechanism of oxygenation improvement after recruitment manoeuvres or prone positioning in acute lung injury or acute respiratory distress syndrome is still unclear. We tried to determine the mechanism responsible for the effects of recruitment manoeuvres or prone positioning on lung aeration using a whole lung computed tomography scan in an oleic acid induced acute lung injury canine model.

Twelve adult mongrel dogs were allocated into either the supine group (n=6) or the prone group (n = 6). After the establishment of acute lung injury, three recruitment manoeuvres were performed at one-hour intervals. Haemodynamic and ventilatory variables, arterial blood gas analyses and CT scans of the whole lung were obtained 90 minutes after oleic acid injection and five minutes before and after each recruitment manoeuvre.

Recruitment manoeuvres in the supine position improved oxygenation (P=0.025) that correlated with increase of the poorly- and well-aerated dorsal (dependent) lung volume (r=0.436, P=0.016). Prone positioning increased oxygenation (P=0.004) that also correlated with increase of the poorly- and well-aerated dorsal (nondependent) lung volume (r=0.787, P <0.001). However, the recruitment manoeuvre in the prone position had no effect on oxygenation despite an increase in ventral (dependent) lung volume. The increase in PO2 after recruitment manoeuvres in the supine position or after prone positioning is related to the increase of the poorly- and well-aerated dorsal lung.
Evaluation of the Efficacy of Magnesium Sulphate as an Adjuvant to Lignocaine for Intravenous Regional Anaesthesia for Upper Limb Surgery
Authors: Narang S. , Dali J. S. , Agarwal M. , Garg R.
Published: January 2019

Several additives have been combined with local anaesthetics for intravenous regional anaesthesia to improve block quality, analgesia and to decrease tourniquet pain. Magnesium sulphate is one potential additive. This prospective, randomised, double-blinded study was conducted in 30 ASA physical status I or II patients undergoing upper limb surgery under tourniquet. In group L, patients received intravenous regional anaesthesia with lignocaine alone (9 ml of 2% lignocaine diluted with normal saline to total volume of 36 ml). Patients in group M received intravenous regional anaesthesia with lignocaine plus magnesium sulphate (6 ml of 25% magnesium sulphate plus 9 ml of 2% lignocaine diluted with normal saline to total volume of 36 ml). Assessment was by observing the response to injection of drug; sensory and motor block and tourniquet pain.

The mean time of onset of sensory block was 12.40 and 3.47 minutes in groups L and M respectively (P <0.001). The average times of onset of motor block in groups L and M were 17 and six minutes respectively (P <0.001). Of the patients in group M, 66.7% reported moderate to severe pain while the drug was being injected, compared to 20% in group L (P=0.011). There was a statistically significant difference in visual analogue scale for tourniquet pain at 10 and 30 minutes after tourniquet inflation (lower in group M).

These findings indicate that magnesium sulphate added as an adjuvant to lignocaine hastens the onset of sensory and motor block and decreases tourniquet pain. However, there is increased incidence of transient pain on injection if magnesium sulphate is added.
Palatopharyngeal wall Perforation during Glidescope® Intubation
Authors: Leong W. L. , Lim Y. , Sla A. T. H.
Published: January 2019

We report a case of palatopharyngeal wall perforation during intubation with a GlideScope® laryngoscope. The likely mechanism was advancing and rotating the endotracheal tube against a taut palatopharyngeal fold. This was missed during the initial laryngoscopy, because there is a potential blind-spot in the oropharynx when attention is focused on the GlideScope® monitor. Fortunately, there were no sequelae other than minor bleeding and a mild sore throat and no surgical intervention was necessary. The use of unnecessary force during the endotracheal tube insertion, the use of too large a laryngoscope blade and the use of a rigid stylet could possibly also have been contributory factors to this complication.
Subdural Block and the Anaesthetist
Authors: Agarwal D. , Mohtaf M. , Tyagi A. , Sethi A. K.
Published: January 2019

There are a number of case reports describing accidental subdural block during the performance of subarachnoid or epidural anaesthesia. However, it appears that subdural drug deposition remains a poorly understood complication of neuraxial anaesthesia. The clinical presentation may often be attributed to other causes. Subdural injection of local anaesthetic can present as high sensory block, sometimes even involving the cranial nerves due to extension of the subdural space into the cranium. The block is disproportionate to the amount of drug injected, often with sparing of sympathetic and motor fibres. On the other hand, the subdural deposition can also lead to failure of the intended block. The variable presentation can be explained by the anatomy of this space. High suspicion in the presence of predisposing factors and early detection could prevent further complications. This review aims at increasing awareness amongst anaesthetists about inadvertent subdural block. It reviews the relevant anatomy, incidence, predisposing factors, presentation, diagnosis and management of unintentional subdural block during the performance of neuraxial anaesthesia.
A Unique Snapshot of Intensive Care Resources in Australia and New Zealand
Authors: Martin J. M. , Hart G. K. , Hicks P.
Published: January 2019

The objective of this study was to analyse and report on the distribution and attributes of intensive care services in Australia and New Zealand for the 2005/2006 financial year. A survey was mailed to 155 Australian and 26 New Zealand intensive care units (ICU) listed on the database of the Australian and New Zealand Intensive Care Society. A descriptive analytical approach was used. Of the 181 ICUs, 177 provided data. In Australia there were 100 public sector and 51 private sector ICUs and in New Zealand, 24 public sector and two private sector ICUs. These units contain 1485 available beds in the public sector and 538 available beds in the private sector. Calculations to determine beds per 100,000 population, medical specialists per 1000 patient days and registered nurses per 1000 patient days showed wide variation. International comparisons are limited by lack of data; however it does appear that intensive care patients in Australia and New Zealand have very good outcomes.
Ocular Surface Bacterial Colonisation in Sedated Intensive Care Unit Patients
Authors: Mela E. K. , Drimtzias E. G. , Christofidou M. K. , Filos K. S. , Anastassiou E. D. , Gartaganis S. P.
Published: January 2019

We investigated the time-dependent ocular surface bacterial colonisation of sedated patients hospitalised in an intensive care unit and aimed to evaluate whether proper topical antibiotic prophylaxis could prohibit corneal infection.

The study lasted 12 months and included 134 patients undergoing sedation and mechanical respiratory support for various medical reasons. Patients hospitalised for less than seven days and those with pre-existing ocular surface pathology were excluded. All patients were examined on admission by inspecting the cornea for erosions. Follow-up examinations were performed each subsequent day. Cultures were also obtained from the conjunctival sac of both eyes on admission and every seventh day until the end of sedation. Standard laboratory techniques were used for isolation, identification and antibiotic susceptibility testing of bacteria. Antibiotic treatment for prophylaxis was administered accordingly.

Analysis was carried out for 70 patients. Duration of sedation ranged from seven to 122 days. Fifty-four (77%) patients were colonised by at least one bacterial species other than normal flora within seven to 42 days. Multiple bacteria were isolated from 28 patients undergoing prolonged sedation. Prevalent isolates were Pseudomonas aeruginosa, Acinetobacter spp. and Staphylococcus epidermidis. Infectious keratitis was prohibited in all cases.

Ocular surface of long-term sedated patients was found to be colonised by various bacterial species and their isolation was closely associated with the time period of hospitalisation. The results of this study suggest that the early identification of ocular surface bacteria colonisation and the administration of topical antibiotics for prophylaxis can prohibit corneal infection in these patients.
Difficult Double-Lumen Tube Placement Due to Laryngeal Web
Authors: Schmidt M. H. , Riley R. H. , Hee G. Y. K.
Published: January 2019

We present a case of difficult intubation in a patient with a laryngeal web. A 33-year-old male patient presented for open thoracotomy and had a previously undiagnosed laryngeal web, which complicated the placement of a double-lumen tube. A single-lumen tube was placed with the use of a bougie through the narrowed airway. With the subsequent use of an airway exchange catheter, a double-lumen tube was positioned. Techniques for managing narrowing of the supraglottic airway are presented and the literature dealing with laryngeal webs is reviewed. In the setting of an unusual airway and thoracic surgery, ventilation via simpler techniques takes precedence over insertion of more complex tubes.
Anaesthesia for Acute Intestinal Obstruction Associated with Cerebral Arteriovenous Malformation in a Child
Authors: Scarth E. J. , White M. C.
Published: January 2019

This case report describes the perioperative management of a child presenting with acute intestinal obstruction secondary to bowel malrotation after a recent intracranial haemorrhage associated with an intracranial arteriovenous malformation. We discuss the anaesthesia planning for this case, where the ‘optimal’ management strategies for the two conditions present are potentially conflicting. Issues include rapid sequence induction in the presence of a ruptured arteriovenous malformation, maintenance of cerebral perfusion pressure in the face of bowel ischaemia, and the use of epidural anaesthesia in a child with recent intracranial haemorrhage.

Written consent was obtained from the patient and parents to publish this case.
Single dose Dexamethasone for Postoperative Nausea and Vomiting – a Matched Case-Control Study of Postoperative Infection Risk
Authors: Percival V. G. , Riddell J. , Corcoran T. B.
Published: January 2019

Dexamethasone is an effective prophylaxis against postoperative nausea and vomiting but is immunosuppressive and may predispose patients to an increased postoperative infection risk. This matched case-control study examined the association between the administration of a single intraoperative anti-emetic dose of dexamethasone (4 to 8 mg) and postoperative infection in patients undergoing non-emergency surgery in a university trauma centre. Cases were defined as patients who developed infection between one day and one month following an operative procedure under general anaesthesia. Controls who did not develop infection were matched for procedure, age and gender. Exclusion criteria included immunosuppressive medications, chronic glucocorticoid therapy, cardiac surgical and solid-organ transplantation procedures. Sixty-three cases and 172 controls were identified. Cases were more likely to have received dexamethasone intraoperatively (25.4 vs 11%, P=0.006), and less likely to have received perioperative antibiotic prophylaxis (60.3 vs 84.3%, P=0.001). Stepwise, multivariate conditional logistic regression confirmed these associations, with adjusted odds ratios of 3.03 (1.06 to 19.3, P=0.035) and 0.12 (0.02 to 0.7, P=0.004) respectively for the associations between dexamethasone and perioperative antibiotic prophylaxis, with postoperative infection. We conclude that intraoperative administration of dexamethasone for anti-emetic purposes may confer an increased risk of postoperative infection.
The Safety of Recombinant Factor VIIa in Cardiac Surgery
Authors: Mitra B. , Phillips L. , Cameron P. A. , Billah B. , Reid C.
Published: January 2019

We investigated whether there was an association between recombinant activated factor VII (rFVIIa) use in cardiac surgery and thromboembolic events by comparing cases in two medical registries. The incidence of thromboembolic events in patients undergoing cardiac surgery (except isolated coronary artery bypass grafts) who had received rFVIIa and were entered into the Australian and New Zealand Haemostasis Registry was compared with the background incidence in patients entered in the Australasian Society for Cardiac and Thoracic Surgeons database. Mortality, length of hospital stay and thromboembolic complications such as stroke, perioperative myocardial infarction and pulmonary embolism data were analysed.

A total of 705 patients in the Registry were compared with 6554 patients in the Thoracic Surgeons database. The use of rFVIIa was independently associated with higher mortality (odds ratio 2.55, P <0.001) and longer hospital stay (odds ratio 1.54, P=0.020). However, multiple regression analyses showed no independent association between rFVIIa and stroke (odds ratio 1.0, P=0.994) or perioperative myocardial infarction (odds ratio 0.29, P=0.053), while the use of rFVIIa was associated with fewer pulmonary emboli (odds ratio 0.02, P <0.001).

These findings indicate that patients who received rFVIIa had increased mortality and length of hospital stay, as expected, but that rFVIIa use was not associated with an increased incidence of stroke or perioperative myocardial infarction. In the absence of randomised controlled clinical trials, this analysis suggests that the off-label use of rFVIIa in cardiac surgery does not significantly increase thromboembolic events.
Modern Blood Filters do not Need to be Routinely Changed for the Majority of Red Blood Cell Transfusions in New Zealand
Authors: Rusk D. M. , Eames P. M.
Published: January 2019

Two experimental studies were undertaken to determine if blood flow rate changes and/or red blood cell damage occurs during red cell transfusion via a single blood filter. In the first study, 12 experiments were performed in each of which four units of group specific human red blood cells, followed by 500 ml 0.9% saline were sequentially run through a blood filter/intravenous giving set system connected to a 14 gauge intravenous cannula positioned two metres below the filter. The second study involved ten experiments with ten units per experiment using the same methodology. In each study, flow rates of each red cell unit/saline were measured. Average flow rates did not decrease with subsequent red cell units in either the four- or ten-unit studies. There was no significant change in blood flow rates across the ten-unit transfusion (P=0.4). In both studies, blood was taken before and after the blood filter from the first, fourth and tenth units of red blood cells, and was measured for haemoglobin, haematocrit, lactate dehydrogenase, potassium, haemolysis levels and red cell morphology. Haemolysis and lactate dehydrogenase levels decreased after blood filtration. Red cell morphology was unchanged in the four-unit study and tended to improve in the ten-unit study. We found no evidence that red blood cell damage is increased during such transfusion.
Glycaemic Fluctuation Predicts Mortality in Critically Ill Patients
Authors: Al-Dorzi H. M. , Tamim H. M. , Arabi Y. M.
Published: January 2019

Growing evidence suggests that glycaemic variability increases diabetic complications. However, the significance of glycaemic variability in critically ill patients remains unclear. We evaluated the predictors of glycaemic fluctuation and its association with critical care outcomes. This is a nested-cohort study within a clinical trial in which 523 patients at a medical surgical intensive care unit were randomised to either intensive insulin therapy (target glycaemic control: 4.4 to 6.1 mmol/l) or conventional insulin therapy (target control: 10.0 to 11.1 mmol/l). Glycaemic fluctuation was defined as the mean difference between the highest and lowest daily blood glucose. Patients were divided into wide and narrow fluctuation groups according to the median glycaemic fluctuation (6.0 mmol/l). The association between glycaemic fluctuation and different intensive care unit outcomes was studied. Predictors of glycaemic fluctuation were age (odds ratio for each year increment 1.03, 95% confidence interval 1.02 to 1.05), diabetes mellitus (odds ratio 3.00, 95% confidence interval 1.74 to 5.17), and daily insulin dose (odds ratio for each unit increment 1.04, 95% confidence interval 1.03 to 1.05). Similar levels of glucose fluctuation were observed in intensive insulin therapy and conventional insulin therapy patients. Wide glycaemic fluctuation was associated with higher mortality (22.2 vs 8.4%, P <0.001). Glycaemic fluctuation was identified as an independent predictor of intensive care unit mortality (odds ratio per mmol 1.08, 95% confidence interval 1.00 to 1.18) and hospital mortality (odds ratio per mmol 1.09, 95% confidence interval 1.02 to 1.17) using multivariate logistic regression analysis. In conclusion, wide glycaemic fluctuation is an independent predictor of mortality in critically ill patients. Whether reducing glycaemic fluctuation would lead to better outcomes needs further evaluation.
Effects of Age and Coronary Artery Disease on Cerebrovascular Reactivity to Carbon Dioxide in Humans
Authors: Galvin S. D. , Celi L. A. , Thomas K. N. , Clendon T. R. , Galvin I. F. , Bunton R. W. , Ainslie P. N.
Published: January 2019

Alterations in cerebrovascular reactivity to CO2, an index of cerebrovascular function, have been associated with increased risk of stroke. We hypothesised that cerebrovascular reactivity is impaired with increasing age and in patients with symptomatic coronary artery disease (CAD). Cerebrovascular and cardiovascular reactivity to CO2 was assessed at rest and during hypercapnia (5% CO2) and hypocapnia (hyperventilation) in subjects with symptomatic CAD (n=13) and age-matched old (n=9) and young (n=20) controls without CAD. Independent of CAD, reductions in middle cerebral artery blood velocity (transcranial Doppler) and cerebral oxygenation (near-infrared spectroscopy) were correlated with increasing age (r=-0.68, r=-0.51, respectively, P <0.01). In CAD patients, at rest and during hypercapnia, cerebral oxygenation was lower (P <0.05 vs young). Although middle cerebral artery blood velocity reactivity was unaltered in the hypercapnic range, middle cerebral artery blood velocity reactivity to hypocapnia was elevated in the CAD and age-matched controls (P <0.01 vs young), and was associated with age (r=0.62, P <0.01). Transient drops in arterial PCO2 occur in a range of physiological and pathophysiological situations, therefore, the elevated middle cerebral artery blood velocity reactivity to hypocapnia combined with reductions in middle cerebral artery blood velocity may be important mechanisms underlying neurological risk with aging. In CAD patients, additional reductions in cerebral oxygenation may place them at additional risk of cerebral ischaemia.
Healthcare Utilisation among Patients Discharged from Hospital after Intensive Care
Authors: Williams T. A. , Leslie G. D. , Brearley L. , Dobb G. J.
Published: January 2019

Surviving critical illness can be life-changing and presents new healthcare challenges for patients after hospital discharge. This feasibility study aimed to examine healthcare service utilisation for patients discharged from hospital after intensive care unit stay. Following Ethics Committee approval, patients aged 18 years and older were recruited over three months. Those admitted after cardiac surgery, discharged to another facility or against medical advice were excluded. Patients were informed of the study by post and followed-up by telephone at two and six months after discharge. General practitioners were also contacted (44% responded). Among 187 patients discharged from hospital, 11 died, 25 declined to participate and 39 could not be contacted. For 112 patients (60%) who completed a survey, the majority (82%) went home from hospital and were cared for by their partner (53%). More than half of the patients (58%) reported taking the same number of medications after intensive care unit stay but 30% took more (P=0.023). While there was no change in the number of visits to the general practitioner for 64% of patients, 29% reported an increase after intensive care unit stay. At six months, 40% of responders who were not retired were unemployed. Discharge summary surveys revealed 39 general practitioners (71%) were satisfied with details of ongoing healthcare needs. Twenty-one general practitioners wrote comments: 10 reported insufficient information about ongoing needs/rehabilitation and two reported no mention of intensive care unit stay. Survivors of critical illness had increased healthcare needs and despite most returning home, had a low workforce participation rate. This requires further investigation to maximise the benefits of survival from critical illness.
Anaesthetic Aspects of Implanting Diaphragmatic Pacing in Patients with Spinal Cord Injury
Authors: Story D. , Mariampillai E. , Nikfarjam M. , Howard M. , Nunn A. , Onders R.
Published: January 2019

Some patients with high cervical spinal cord injury are largely or completely dependent on mechanical ventilator support. Diaphragmatic phrenic nerve pacing is a new technique that offers some patients greater independence from mechanical ventilation. In selected patients, electrodes are placed on the abdominal side of the diaphragm via laparoscopy. An external pacing box provides the pacing stimulus. We report our experience with four patients with spinal cord injury in a pilot project, presenting for laparoscopic insertion of diaphragmatic phrenic nerve pacing leads inserted. The surgery took about two hours and diaphragmatic mapping precluded muscle relaxants. We used desflurane with remifentanil for maintenance. Apart from transferring the patients to and from their usual ventilators, other anaesthesia issues were difficult venous and arterial access for lines and long-term tracheostomies with no cuff or cuffs filled with water. While hypotension was a frequent problem, one patient also developed intraoperative hypertension secondary to autonomic dysreflexia. Preoperative testing predicted pacing outcome with three of the four patients having successful pacing with tidal volumes of up to 10 ml/kg at the end of surgery. This initial Australian experience may lead to greater use of the technique.
Computer Based Haemodynamic Guidance System is Effective and Safe in Management of Postoperative Cardiac Surgery Patients
Authors: Pellegrino V. A. , Mudaliar Y. , Gopalakrishnan M. , Horton M. D. , Killick C. J. , Parkin W. G. , Playford H. R. , Raper R. F.
Published: January 2019

A circulatory guidance system, Navigator™, was evaluated in a prospective, randomised control trial at six Australian university teaching hospitals involving 112 scheduled postoperative cardiac surgical patients with pulmonary artery catheters placed and receiving 1:1 nursing care. The guidance system was used to achieve and maintain physician-designated cardiac output and mean arterial pressure targets and compared these with standard post open-heart surgery care. The primary efficacy endpoint was the standardised unsigned error between the targeted and the actual values for cardiac output and mean arterial pressure, time averaged over the duration of cardiac output monitoring – the average standardised distance. This was 1.71 (SD=0.65) for the guidance group and 1.92 (SD=0.65) in the control group (P=0.202). Rates of postoperative atrial fibrillation, adverse events, intensive care unit and hospital length-of-stay were similar in both groups. There were no device-related adverse events. Guided haemodynamic therapy with the Navigator™ device was non-inferior to standard intensive care unit therapy. The study was registered with ClinicalTrials.gov Identifier NCT00468247.
Non-Invasive Ventilation after Extubation in Patients with Chronic Obstructive Airways Disease: A Randomised Controlled Trial
Authors: Khilnani G. C. , Galle A. D. , Hadda V. , Sharma S. K.
Published: January 2019

Non-invasive positive pressure ventilation (NPPV) is a well established therapy for acute respiratory failure in patients with chronic obstructive pulmonary disease, however its role in post-extubation period is uncertain. The objective of this study was to find the effect of NPPV on rate of re-intubation, intensive care unit and hospital stay, and physiological parameters in severe chronic obstructive pulmonary disease patients after planned extubation. Forty patients with severe chronic obstructive pulmonary disease were randomised immediately after planned extubation to receive NPPV (n=20) or conventional therapy (n=20). NPPV was delivered with mean levels of inspiratory positive-airway pressure of 12.10±1.37 cmH2O and expiratory positive-airway pressure of 6.50±1.00 cmH2O for a mean period of 34.75±10 hours for 7 to 11 hours/day. Patients in conventional therapy group received usual treatment. Reintubation rate among NPPV (15%) and conventional (25%) were similar (P=0.44). The duration of intensive care unit stay after extubation (2.05±2.15 vs 1.55±0.82 days, P=0.34) and hospital stay (16.10±6.29 vs 18.25±7.91 days, P=0.34) in both groups were comparable. Given the load of chronic obstructive pulmonary disease patients and wide availability of NPPV, it is safe to recommend its use in these patients soon after extubation, although clear benefit is not documented in this study.
Eosinopenia as a Diagnostic Marker of Bloodstream Infection in Hospitalised Paediatric and Adult Patients: A Case-Control Study
Authors: Wibrow B. A. , Ho K. M. , Flexman J. P. , Keil A. D. , Kohrs D. L.
Published: January 2019

The objective of this study was to assess whether eosinopenia was a reliable diagnostic marker of bloodstream infection in hospitalised adult and paediatric patients. The design was a case-control study, set in a tertiary adult and paediatric hospital.

A total of 157 adult and 85 paediatric patients with bloodstream infection (‘cases’) were compared to 195 and 94 randomly selected adult and paediatric patients who had clinical suspicion of bloodstream infection but with a negative blood culture (‘controls’) respectively. Patients with haematological or immunosuppressive disease and control patients who were treated with antibiotics within one week prior to the blood culture were excluded.

Eosinopenia, or undetectable eosinophil count (<0.01×109 or >10/mm3), was more common among the cases than the controls (46.5% vs 21.5%, respectively). The specificity of eosinopenia to predict bloodstream infection in adult patients was reasonable (79%, 95% confidence interval [CI] 74 to 82), but its sensitivity was low (47%, 95% CI 41 to 52). The absolute eosinophil count only had a modest ability to discriminate bloodstream infections from controls in adult patients (area under receiver operating characteristic curve 0.349, 95% CI 0.288 to 0.411). Eosinophil counts had very little overall predictive ability (area under receiver operating characteristic curve 0.448, 95% CI 0.363 to 0.533, P=0.237), and the sensitivity (54%, 95% CI 47 to 61) and specificity (56%, 95% CI 49 to 63) of eosinopenia to predict bloodstream infection in paediatric patients were both low. In the multivariate analyses, only C-reactive protein concentrations and neutrophil counts, but not eosinopenia, were significantly associated with the presence of bloodstream infection in both adult and paediatric patients.

The presence of eosinopenia can be considered as an inexpensive warning test for bloodstream infection in hospitalised adult patients so that further investigations can be initiated. An absence of eosinopenia is, however, not sensitive enough to exclude bloodstream infection. C-reactive protein concentrations and neutrophil counts were both better markers of bloodstream infection than eosinopenia in hospitalised paediatric and adult patients.
Analysis of Human Cultured Myotubes Responses Mediated by Ryanodine Receptor 1
Authors: Kobayashi M. , Mukaida K. , Migita T. , Hamada H. , Kawamoto M. , Yuge O.
Published: January 2019

Malignant hyperthermia is a life-threatening condition caused by autosomal dominant mutations in the ryanodine receptor type 1 gene. Identifying patients predisposed to malignant hyperthermia is done through the Ca-induced Ca release test in Japan. We examined the intracellular calcium concentration in human cultured muscle cells and compared the sensitivity of myotubes to ryanodine receptor type 1 activators based on the Ca-induced Ca release rate. We assessed the utility of this method as an identifying test for predisposition to malignant hyperthermia.

Muscle specimens were obtained from 34 individuals undergoing the Ca-induced Ca release test. We cultured myotubes from residual material and monitored changes in intracellular calcium concentration after exposure to the ryanodine receptor type 1 activators caffeine, halothane and 4-chloro-m-cresol by measuring fura-2 fluorescence. We determined the half maximal effective concentrations (EC50) for the test compounds in each myotube and calculated cut-off points using receiver operating characteristic curves. Seventeen patients each were classified into the accelerated and non-accelerated groups based on their Ca-induced Ca release rate. The EC50 values for caffeine, halothane and 4-chloro-m-cresol of the accelerated group were significant lower than those of the non-accelerated group (P <0.001, P <0.001 and P <0.001, respectively). The calculated cut-off points of EC50 values for caffeine, halothane and 4-CmC were 3.62 mM, 2.28 mM and 197 μM, respectively. An increased sensitivity to ryanodine receptor type 1 activators was seen in myotubes in the accelerated group. This functional test on human cultured myotubes indicates that the alteration of their intracellular Ca2+ homeostasis may identify the predisposition to malignant hyperthermia.
Anaphylaxis and other Adverse Reactions to Blue Dyes: A Case Series
Authors: Howard J. D. , Moo V. , Sivalingam P.
Published: January 2019

We report three cases of anaphylaxis during anaesthesia confirmed on intradermal testing to be related to patent blue V dye (Guerbet – Chemical Abstract Service 3536-49-0). All three cases were associated with moderate to severe hypotension. Two cases had delayed onset, and two were associated with a rash. None of the cases were associated with bronchospasm. In all three patients the interference with pulse oximetry readings contributed to difficulties in management. We recommend the use of a test dose of blue dye prior to surgery, as suggested in the manufacturer's product information. We also recommend high vigilance for possible allergic reactions when patent blue dyes are used for sentinel lymph node mapping, because the presentations may be atypical and the reduced pulse oximetry readings may be a distraction.
Emergency Caesarean Section in a Patient with Myotonic Dystrophy: A Case of Failed Postoperative Extubation in a Patient with Mild Disease
Authors: Owen P. M. , Chu C.
Published: January 2019

A 21-year-old primiparous patient with subclinical myotonic dystrophy presented at a tertiary hospital at 38 weeks gestation in active labour, having previously been reviewed in the high-risk pregnancy clinic. A non-reassuring cardiotocogram and raised foetal scalp lactate necessitated an emergency caesarean section. On extubation following an otherwise unremarkable general anaesthetic, the patient required prompt re-intubation due to respiratory compromise, followed by a more gradual period of weaning from positive pressure ventilation. This review explores the implications of myotonic dystrophy for anaesthesia, discusses its multi-system involvement and highlights the difficulties in identifying at-risk patients in the perioperative setting.
Retraction of Articles with Misleading Information
Authors: Gibbs N. M.
Published: January 2019

In March this year, the editors-in-chief of 18 journals signed a joint statement “regarding published clinical trials conducted without IRB approval by Joachim Boldt”. This statement now appears on their respective journal websites (e.g. www.aaeditor.org/EIC.Joint.Statement.on.Retractions.pdf ). The statement includes a list of 88 articles authored or co-authored by Joachim Boldt for which no record of institutional review board (IRB) approval can be found. The signatories indicate that they have already retracted, or will shortly retract these articles from their journals. Anaesthesia and Intensive Care is not included on the list of signatories only because none of the 88 articles were published in Anaesthesia and Intensive Care. However, Anaesthesia and Intensive Care was included in the correspondence leading to the publication of the joint statement.
Does the Pulmonary Artery Catheter Still Have a Role in the Perioperative Period?
Authors: Cowie B. S.
Published: January 2019

The pulmonary artery catheter (PAC) was introduced into clinical practice in the early 1970s. Its use quickly expanded beyond patients with acute myocardial infarction to critically ill patients in the intensive care unit. Increasingly, it was used in the perioperative period in patients having major cardiac and noncardiac surgery. Publication of large observational studies suggested that patients with a PAC were more likely to suffer major morbidity or mortality, but this was difficult to assess because patients who had a PAC inserted were often sicker, with more severe pathology, and were therefore more likely to die. The PAC is a monitoring device and information alone is unlikely to influence outcome unless it is linked to a proven therapy. Several thousand articles on the use of the PAC now exist, but in general, the quality of this literature is poor. Much of the data are not randomised, have small sample sizes and include patients with greatly differing pathological states. It is unclear which, if any, of the PAC-guided therapies are actually beneficial for patients. Despite these flaws, there is no clear evidence of benefit, nor harm, in cardiac, intensive care or perioperative patients. Selected indications for the PAC may remain, such as complex cardiac surgery or solid organ transplantation. However, its routine use is difficult to justify and increasingly, most of the haemodynamic data available from the PAC can be obtained less invasively with echocardiography.
Erythropoietin as a Novel Brain and Kidney Protective Agent
Authors: Moore E. M. , Bellomo R. , Nichol A. D.
Published: January 2019

Erythropoietin is a 30.4 kDa glycoprotein produced by the kidney, which is mostly known for its physiological function in regulating red blood cell production in the bone marrow. Accumulating evidence, however, suggests that erythropoietin has additional organ protective effects, which may specifically be useful in protecting the brain and kidneys from injury. Experimental evidence suggests that these protective mechanisms are multi-factorial in nature and may include inhibition of apoptotic cell death, stimulation of cellular regeneration, inhibition of deleterious pathways and promotion of recovery.

In this article we review the physiology of erythropoietin, assess previous work that supports the role of erythropoietin as a general tissue protective agent and explain the mechanisms by which it may achieve this tissue protective effect. We then focus on specific laboratory and clinical data that suggest that erythropoietin has a strong brain protective and kidney protective effect. In addition, we comment on the implications of these studies for clinicians at the bedside and for researchers designing controlled trials to further elucidate the true clinical utility of erythropoietin as a neuroprotective and nephroprotective agent.

Finally, we describe EPO-TBI, a double-blinded multi-centre randomised controlled trial involving the authors that is being conducted to investigate the organ protective effects of erythropoietin on the brain, and also assesses its effect on the kidneys.
Observational Study of Anaesthetists’ Fresh Gas Flow Rates during Anaesthesia with Desflurane, Isoflurane and Sevoflurane
Authors: Dexter F. , Maguire D. , Epstein R. H.
Published: January 2019

Reducing excessive fresh gas flow rates (FGF) is an established and simple strategy to reduce the administration of volatile anaesthetic agents. We studied clinicians’ FGF use to understand better why two previous clinical trials achieved significant reductions in FGF by using feedback to anaesthetists.

Anaesthesia information management system data from a US academic medical centre were analysed retrospectively. One year of data starting from July 2008 had 11,170 cases. Fresh gas flow rates were measured each minute during cases.

Anaesthetists were more likely to choose FGF of multiples of 1 l/minute and 0.5 l/minute than random. However, the pattern was too inconsistent to be of economic or psychological importance and thus is not needed when describing a target FGF.

Cumulative distributions of FGF were shifted to the left for desflurane and isoflurane compared to sevoflurane (i.e. cost comparisons among agents may need to use different target FGF).

Variation in mean FGF among anaesthetists was small. Even if all anaesthetists had identical mean FGF, the standard deviation of FGF among cases would be reduced by less than 0.1 l/minute for all agents. Most of the achievable reductions in FGF were small reductions in FGF for the many cases with <3 l/minute.

These results show that departments choosing to use inexpensive automatic email feedback on FGF should target all anaesthetists and focus on variation in FGF among anaesthetists’ cases.
Anaesthesia Trainees’ Exposure to Regional Anaesthesia in an Australian Tertiary Adult Teaching Hospital
Authors: Russell T. , Clarke R. , Gardner A. , Hennessy B. , Watts S. A.
Published: January 2019

The purpose of this study was to quantify the exposure of anaesthetic trainees to regional anaesthesia in an Australian tertiary adult teaching hospital. We reviewed data collected on all regional blocks performed by the anaesthetic department over a two-year period. The data was then broken down to give an estimate of the number of each block performed by each training year group. There was an average of 27.7 full-time equivalent trainees attached to the department. Trainees performed a total of 1374 blocks over this period. The average number of blocks performed by basic training year one trainees each year was 6.5, basic training year two trainees 13.5, advanced training year one trainees 14.9, advanced training year two trainees 19.1, advanced training year three trainees 23.1 and regional fellows 144.0. The number of total blocks and the proportion of advanced blocks increased with increasing level of training while supervision declined. Trainees in the two regional fellowship positions (7% of the trainee pool) performed 42% of the 1374 blocks. Factors that may influence the exposure of trainees to regional anaesthesia and the assessment of competency are considered.
Opioids, Ventilation and Acute Pain Management
Authors: Macintyre P. E. , Loadsman J. A. , Scott D. A.
Published: January 2019

Despite the increasing use of a variety of different analgesic strategies, opioids continue as the mainstay for management of moderate to severe acute pain. However, concerns remain about their potential adverse effects on ventilation. The most commonly used term, respiratory depression, only describes part of that risk. Opioid-induced ventilatory impairment (OIVI) is a more complete term encompassing opioid-induced central respiratory depression (decreased respiratory drive), decreased level of consciousness (sedation) and upper airway obstruction, all of which, alone or in combination, may result in decreased alveolar ventilation and increased arterial carbon dioxide levels.

Concerns about OIVI are warranted, as deaths related to opioid administration in the acute pain setting continue to be reported. Risks are often said to be higher in patients with obstructive sleep apnoea. However, the tendency to use the term ‘obstructive sleep apnoea’ to encompass the much broader spectrum of sleep- and obesity-related hypoventilation syndromes and the related misuse of terminology in papers relating to obstructive sleep apnoea and sleep-disordered breathing remain significant problems in discussions of opioid-related effects.

Opioids given for management of acute pain must be titrated to effect for each patient. However, strategies aiming for better pain scores alone, without highlighting the need for appropriate monitoring of OIVI, can and will lead to an increase in adverse events. Therefore, all patients must be monitored appropriately for OIVI (at the very least using sedation scores as a ‘6th vital sign’) so that it can be detected at an early stage and appropriate interventions triggered.