bluuebunny/crossref_metadata_2025 huggingface dataset:
Focused Transthoracic Echocardiography in the Perioperative Period
Authors: Cowie B. S.
Published: January 2019

Ultrasound applications in perioperative medicine have expanded enormously over the past decade. Transoesophageal echocardiography has been performed by anaesthetists during cardiac surgery for over 20 years. With the increasing availability of portable ultrasound systems, the use of ultrasound to assist in vascular cannulation and regional anaesthesia has been well described. Portable ultrasound systems come with a range of probes for different applications, including transthoracic echocardiography. While transthoracic echocardiography has traditionally been the domain of cardiologists, its use has been increasing in critical care, the emergency room and, recently, by anaesthetists in the perioperative period. Unlike formal cardiology-based transthoracic echocardiography, focused, goal-directed transthoracic echocardiography is often more appropriate in the perioperative period to address a particular question and can be performed in just a few minutes. Transthoracic echocardiography allows rapid, noninvasive, point-of-care assessment of ventricular function, valvular integrity, volume status and fluid responsiveness. It can help distinguish undifferentiated systolic murmurs preoperatively, give valuable information on the aetiology of unexplained hypotension and cardiovascular collapse and assess response to therapeutic interventions such as vasoactive drugs and volume resuscitation. Focused transthoracic echocardiography should include qualitative assessment of left and right ventricular function, an estimate of aortic valve gradient, right ventricular systolic pressure and intravascular volume status as minimum requirements. Transthoracic echocardiography is a valuable tool in the perioperative period and ideally the equipment and expertise should be available in all operating rooms.
Intraoperative Nitrous Oxide as a Preventive Analgesic
Authors: Stiglitz D. K. , Amaratunge L. N. , Konstantatos A. H. , Lindholm D. E.
Published: January 2019

Preventive analgesia is defined as the persistence of the analgesic effects of a drug beyond the clinical activity of the drug. The N-methyl D-aspartate receptor plays a critical role in the sensitisation of pain pathways induced by injury. Nitrous oxide inhibits excitatory N-methyl D-aspartate sensitive glutamate receptors. The objective of our study was to test the efficacy of nitrous oxide as a preventive analgesic. We conducted a retrospective analysis of data from a subset of patients (n=100) randomly selected from a previous major multicentre randomised controlled trial on nitrous oxide (ENIGMA trial). Data analysed included postoperative analgesic requirements, pain scores and duration of patient-controlled analgesia during the first 72 postoperative hours. There was no significant difference in postoperative oral morphine equivalent usage (nitrous group 248 mg, no nitrous group 289 mg, mean difference -43 mg, 95% confidence interval 141 to 54 mg). However, patients who received nitrous oxide had a shorter duration of patient-controlled analgesia use (nitrous group 35 hours, no nitrous group 51 hours, mean difference -16 hours, 95% confidence interval -29 to -2 hours, P=0.022). There was no difference in pain scores between the groups. The shorter patient-controlled analgesia duration in the nitrous oxide group suggests that intraoperative nitrous oxide may have a preventive analgesic effect.
Out-of-Hours Surgery – a Snapshot in Time
Authors: O'Loughlin E. , Smithies W. J. , Corcoran T. B.
Published: January 2019

Anaesthesia in Australia is amongst the safest in the world. This record of safety is under threat from increasing pressures to operate at times of poor human performance, particularly late at night. Our institution has a policy mandating the prioritisation of surgery based on clinical need while minimising the risks associated with after-hours surgery. The policy states that “only Category 1 (urgent, needing immediate surgery) and Category 2 cases which cannot wait until the morning should be done between 2230 and 0800”. From 5 March 2007 we performed an eight-week prospective audit of all cases where surgery occurred in this time period. The anaesthetic senior registrar on duty recorded the clinical priority of the case. There were 95 cases commenced between 2230 and 0800 hours during the audit period, of which 28 (30%) were in clear breach of this policy, in some cases delaying urgent surgery. The potential implications of such breaches are significant in the context of worse outcomes for patients undergoing surgery in the after-hours period. When non-urgent cases occupy resources, the capacity of the system to deal with the truly urgent case is significantly impaired.

Adequate ‘in-hours’ resourcing, capacity and appropriate scheduling may be key to maintaining the excellent safety record of anaesthesia. A large study prospectively examining morbidity, error and outcomes of after-hours operating would serve to further elucidate the risk benefit ratio of after-hours operating.
Surgical Emphysema as a Cause of Severe Hypercapnia during Laparoscopic Surgery
Authors: Critchley L. A. H. , Ho A. M-H.
Published: January 2019

Surgical emphysema is a well-recognised complication of laparoscopic surgery, but its impact on end-tidal carbon dioxide levels and carbon dioxide elimination is seldom reported and may not be fully appreciated by anaesthetists. Four cases are presented where extensive surgical emphysema occurred during laparoscopic surgery. The visual display of the anaesthetic record using the software program Monitor showed substantial rises in end-tidal carbon dioxide levels and allowed calculation of the carbon dioxide elimination, which increased two- to three-fold above normal levels. Having a visual record of carbon dioxide changes facilitated the recognition of surgical emphysema in three out of the four cases. Strategies such as estimating and tracking changes in carbon dioxide elimination from the minute ventilation and end-tidal carbon dioxide levels may assist in early identification, and palpating for surgical emphysema is recommended during laparoscopy if other causes of increased carbon dioxide levels are excluded.
Ultrasound-Guided Axillary Plexus Block in a Child with Dystrophic Epidermolysis Bullosa
Authors: Englbrecht J. S. , Langer M. , Hahnenkamp K. , Ellger B.
Published: January 2019

We report the use of ultrasound-guided axillary brachial plexus block in a child with dystrophic epidermolysis bullosa needing surgical treatment of the right hand. The regional anaesthesia was used in association with sedation/anaesthesia. This technique is suitable for these difficult patients because it can minimise the risk of new bullae formation due to palpation of landmarks or unintentional intra- or subcutaneous injections. Initial anaesthesia/sedation was provided with sevoflurane until intravenous access was obtained, following which intravenous propofol infusion with ketamine boluses without any invasive airway management was continued for performance of the block and the procedure. This management plan provided good surgical conditions, early postoperative analgesia, minimised stress for the patient and avoided the need to manipulate the airway with instruments and the associated risk of mucosal bullae.

The classification and breadth of clinical manifestation of epidermolysis bullosa is complex and briefly summarised. The anaesthetist should clarify the details of a particular patient's form of epidermolysis bullosa, especially in terms of mucosal involvement, as this may greatly influence planning for a procedure.
Low-Dose Remifentanil Infusion during Ventilator Weaning and Tracheal Extubation in Postoperative Intensive Care Unit Patients Sedated with Propofol-Remifentanil: A Randomised Clinical Trial
Authors: Kim S. Y. , Yang S. Y. , Na S. W. , Jo Y. Y. , Koh S. O.
Published: January 2019

Discontinuation of sedatives for ventilator weaning and extubation can be associated with hyperdynamic responses, including hypertension and tachycardia. We examined the effects of a maintained low dose of remifentanil infusion on cardiovascular responses and coughing during extubation in postoperative intensive care unit patients sedated with propofol-remifentanil.

Fifty patients who required mechanical ventilation after major abdominal surgery were randomised into remifentanil group (n=25) or control group (n=25). Sedation during mechanical ventilation was maintained with remifentanil and propofol via a target-controlled infusion system. These drugs were titrated to the target sedation range, bispectral index values of 60 to 75 and Richmond Agitation Sedation Scale values of −3 to −2. When weaning was initiated, propofol was stopped in both groups. In the control group, remifentanil infusion was also stopped; in the remifentanil group, remifentanil infusion was maintained until extubation at a target effect site concentration of 1.0 ng/ml. Extubation was performed if the patient's respiratory, haemodynamic states were stable and if the patient was able to follow commands. Heart rate, mean arterial pressure and cough severity were evaluated.

The mean arterial pressure, heart rate and cough severity did not differ between the two groups during extubation. The time from stopping of propofol infusion to extubation was significantly longer in the remifentanil group compared to that in the control group (P=0.020).

Maintaining a low-dose remifentanil infusion during ventilator weaning delayed tracheal extubation without any differences in haemodynamic changes or coughing in postoperative intensive care unit patients.
The Development and Preliminary Evaluation of a Proposed New Scoring System for Videolaryngoscopy
Authors: Swann A. D. , English J. D. , O'Loughlin E. J.
Published: January 2019

Clear documentation of anaesthetic technique, difficulties and complications is an essential part of good anaesthetic practice, particularly in the area of airway management. The current convention of describing intubation using a videolaryngoscope only in terms of a Cormack and Lehane score is at best unhelpful and at worst dangerous. In an attempt to address the inadequacy of a Cormack and Lehane score to describe videoscopic intubation, we propose a three part scoring system: view, ease and device - the ‘Fremantle Score’. Preliminary evaluation of this system in a diverse group of anaesthetists utilising four available videolaryngoscopes in a simulated normal and difficult airway manikin has demonstrated that the system is easy to use, easy to understand and relevant.

In three of the eight device and manikin combinations studied, the videolaryngoscopic view correlated with the ease of intubation. This highlights the need for an alternative tool to describe intubation with a videolaryngoscope.

We consider this development of a specific videoscopic scoring system a first step in better describing intubation by a videolaryngoscope and improving patient care.
Audit of Cardiac Pathology Detection Using a Criteria-Based Perioperative Echocardiography Service
Authors: Faris J. G. , Hartley K. , Fuller C. M. , Langston R. B. , Royse C. F. , Veltman M. G.
Published: January 2019

Transthoracic echocardiography is often used to screen patients prior to non-cardiac surgery to detect conditions associated with perioperative haemodynamic compromise and to stratify risk. However, anaesthetists’ use of echocardiography is quite variable. A consortium led by the American College of Cardiology Foundation has developed appropriate use criteria for echocardiography. At Joondalup Hospital in Western Australia, we have used these criteria to order echocardiographic studies in patients attending our anaesthetic preadmission clinic. We undertook this audit to determine the incidence of significant echocardiographic findings using this approach. In a 22-month period, 606 transthoracic echocardiographic studies were performed. This represented 8.7% of clinic attendees and 1.7% of all surgical patients. In about two-thirds of the patients, the indication for echocardiography was identified on the basis of a telephone screening questionnaire. The most common indications were poor exercise tolerance (27.4%), ischaemic heart disease (20.9%) and cardiac murmurs (16.3%). Over 26% of patients studied had significant cardiac pathology (i.e. moderate or severe echocardiographic findings), most importantly moderate or severe aortic stenosis (8.6%), poor left ventricular function (7.1%), a regional wall motion abnormality (4.3%) or moderate or severe mitral regurgitation (4.1%). Using appropriate use criteria to guide ordering transthoracic echocardiography studies led to a high detection rate of clinically important cardiac pathology in our perioperative service.
Long-Term Use of Nerve Block Catheters in Paediatric Patients with Cancer Related Pathologic Fractures
Authors: Burgoyne L. L. , Pereiras L. A. , Bertani L. A. , Kaddoum R. N. , Neel M. , Faughnan L. G. , Anghelescu D. L.
Published: January 2019

We report three cases of children with osteosarcoma and pathologic fractures treated with long-term continuous nerve blocks for preoperative pain control.

One patient with a left distal femoral diaphysis fracture had a femoral continuous nerve block catheter for 41 days without complications. Another with a fractured left proximal femoral shaft had three femoral continuous nerve block catheters for 33, 26 and 22 days respectively. The third patient, whose right proximal humerus was fractured, had a brachial plexus continuous nerve block catheter for 36 days without complication.

In our experience, prolonged use of continuous nerve block is safe and effective in children with pathologic fractures for preoperative pain control.
Gabapentin in the Treatment of Post-Dural Puncture Headache: A Case Series
Authors: Wagner Y. , Storr F. , Cope S.
Published: January 2019

Gabapentin has been reported to be useful in the management of epilepsy, neuropathic pain and post-dural puncture headache. Seventeen obstetric cases are presented in which gabapentin was used either as a primary therapy for the management of severe headache following a diagnosed dural puncture or as an analgesic adjunct in patients with dural puncture headache unresponsive to epidural blood patch. In our patients, analgesic therapy was essential to enable care of their newborns as other management options had failed or were unavailable. In nine patients we observed an excellent result with reduction of headache severity within 24 hours. Gabapentin appears potentially beneficial in the management of patients with post-dural puncture headaches.
Blood Culture Collection in Patients with Acute Kidney Injury Receiving Renal Replacement Therapy: An Observational Study
Authors: Ostrowski J. , Paterson D. L. , Lipman J. , Udy A. A.
Published: January 2019

Critically ill patients receiving renal replacement therapy (RRT) for acute kidney injury (AKI) have high reported intensive care unit (ICU) mortality. Blood culture (BC) collection practices in this population have to date been poorly characterised, specifically in regards to the influence of RRT on the clinical triggers for such an investigation. Utilising our electronic clinical information system, we conducted a retrospective observational study of patients admitted to a 30-bed tertiary level ICU and requiring RRT over a four-year period. Patients with a history of chronic kidney disease, prior RRT or ICU length-of-stay (LOS) <48 hours were excluded. Two hundred and thirty-one patients treated with RRT for AKI were identified. The observed median [interquartile range] BC collection rate in those having them drawn was 18 [11-32] per 100 patient days, although 42% of the cohort had no BC drawn during their ICU stay. Application of RRT in the 24 hours prior to initial BC collection was associated with lower body temperatures, higher white cell counts and greater use of vasopressor therapy. Bloodstream infection (identified from the first BC) was associated with greater ICU and in-hospital mortality. We also observed a predominance of candidaemia in this cohort, despite the absence of neutropenia. This study provides unique data describing BC collection rates in a cohort of critically ill patients receiving RRT for AKI and at high risk of dying. Further study of temperature alteration, detection of bloodstream infection and outcome in patients receiving RRT is now warranted.
Therapeutic Hypothermia following Out-Of-Hospital Cardiac Arrest (Ohca): An Audit of Compliance at a Large Australian Hospital
Authors: Mcgloughlin S. A. , Udy A. , O'Donoghue S. , Bandeshe H. , Gowardman J. R.
Published: January 2019

Therapeutic hypothermia (TH) is now largely considered the standard of care for patients following out-of-hospital cardiac arrest caused by ventricular arrhythmias, although the effective implementation of TH for individual patients can be challenging. This study aimed to document the effectiveness of TH when it is used at the discretion of treating physicians and not under the auspices of a research trial or protocol. A retrospective review of intensive care unit admissions over a four-year period detected 43 patients appropriate for TH. In the emergency department, only 20% of patients had TH commenced. Forty-four percent of patients required angiography in the cardiac catheterisation laboratory. It took, on average, 595 minutes for patients to reach their goal temperature, which was not reached at all in 13% of patients. Nineteen patients (44%) had a positive neurological outcome while 24 patients (56%) either died or had a poor neurological outcome. Without the control of a hospital protocol it was apparent that the implementation of TH in patients with an out-of-hospital cardiac arrest in our institution was inadequate. We recommend that TH is undertaken within the framework of a protocol that encompasses all the relevant departments.
A Pilot Study of Short-Term High-Pressure Support Ventilation in Persistent Sudden-Onset Rapid Breathing
Authors: Duan J. , Tang X. , Huang S. , Jia J. , Guo S.
Published: January 2019

Sudden-onset rapid breathing commonly occurs in previously calm, invasively-ventilated patients. In most cases it can be resolved easily by traditional management techniques, but other cases can be very challenging. We enrolled 40 patients who failed traditional interventions and performed short-term high-pressure support ventilation (HPSV). Thirty-three (83%) patients were responsive to HPSV. In the responders, ten minute HPSV reduced mean airway pressure (P=0.030), minute ventilation (P P P P P=0.007). After 58 minutes, HPSV relieved tachypnoea. However, compared with the responders, the non-responders (7/40, 17%) were younger (77.0 versus 59.7 years, P=0.002), and had higher Glasgow Coma Scale score (9.0 versus 14.0, P P=0.029), peak pressure (P=0.048) and heart rate (P=0.004) before sudden-onset rapid breathing. The non-responders also had higher peak pressure (P=0.046), minute ventilation (P=0.024), respiratory rate (P=0.027) and heart rate (P <0.001) when the rapid breathing happened. At or before sudden-onset rapid breathing, peak pressure, minute ventilation and heart rate had a high accuracy to predict the non-responsive patients (each with area under the curve of ≥0.7). The age and Glasgow Coma Scale also had high predicted ability (both with areas under the curve of ≥0.8). In conclusion, short-term HPSV relieved persistent sudden-onset rapid breathing. However, it was not effective in the relatively young and conscious patients with relatively high support pressure, peak pressure, minute ventilation and heart rate.
A Prospective, Observational Study Comparing Postoperative Residual Curarisation and Early Adverse Respiratory Events in Patients Reversed with Neostigmine or Sugammadex or after Apparent Spontaneous Recovery
Authors: Cammu G. V. , Smet V. , De Jongh K. , Vandeput D.
Published: January 2019

Six years ago, a study performed in our department reported that the incidence of postoperative residual curarisation (PORC) was 39%. The reassessment of neuromuscular monitoring and reversal of neuromuscular block in routine anaesthetic practice is relevant now that sugammadex has become available.

The incidence of PORC, defined by a train-of-four (TOF) <90%, was evaluated at post-anaesthesia care unit (PACU) arrival in patients whose neuromuscular block had been reversed with neostigmine or sugammadex and those in whom reversal was felt unnecessary (adequate spontaneous recovery). During the PACU stay we recorded the oxygen saturation (SpO2) at arrival, episodes of SpO2 <90%, airway manoeuvres and/or stimulation required to maintain SpO2 >90%, and the need for re-intubation. In total, 624 patients were studied. Fifteen percent (66/441) of the patients who were not reversed, 15% (21/139) of those who were reversed with neostigmine and 2% (1/44) of those who received sugammadex exhibited PORC (P=0.06). No patient required reintubation in the PACU. The absence of neuromuscular monitoring and pharmacological reversal before extubation were not associated with PORC. A TOF <90% at PACU arrival was not associated with SpO2 <90% during the PACU stay. Body mass index was the only independent predictor of SpO2 <90% during the stay in the PACU.

These findings indicate that in recent years, the incidence of PORC, defined by a TOF <90%, has dramatically decreased in our institution. The differences in PORC were not statistically significant between patients who received sugammadex for reversal and patients with spontaneous recovery or neostigmine reversal.
Uptake of Guidelines in the Management of Patients Taking Anticoagulants and Antiplatelet Agents Presenting for Elective Surgery
Authors: Cheung K. , Halliwell R. , Cope L. , Khong D.
Published: January 2019

Management guidelines for patients on antithrombotic agents presenting for surgery have long been disseminated. Clinical practice, however, does not always follow published guidelines in a timely manner, despite their dissemination. This project is an audit of the management of patients on anticoagulants or antiplatelet agents presenting for elective surgery in a large metropolitan teaching hospital. An audit was conducted of the management of patients on anticoagulants or antiplatelet agents presenting for elective surgery at Westmead Hospital to determine the percentage of patients whose management complied with guidelines, and to identify the prevailing reasons for guideline deviation. This was an observational study with qualitative and quantitative aspects. Data was collected for the 102 patients who fulfilled the inclusion criteria: 55.4% of decisions by surgeons and 51.4% of decisions by anaesthetists made in this study matched guidelines; 31.4% of decisions made by anaesthetists were fully compliant with guidelines; 20% of anaesthetic decisions were unintentionally compliant and 48.6% of anaesthetic decisions were noncompliant. A variety of reasons were cited for decisions made without the use of guidelines such as other clinical imperatives, lack of guideline awareness and a belief that it is not the role of the anaesthetist to manage perioperative antithrombotic therapy, amongst others. It is evident from this audit that compliance with guidelines remains an area where there is an opportunity for further practice improvement.
Is Suppression of Apoptosis a New Therapeutic Target in Sepsis?
Authors: Harjai M. , Bogra J. , Kohli M. , Pant A. B.
Published: January 2019

Sepsis remains as a leading cause of death in critically ill patients. Unfortunately, there have been very few successful specific therapeutic agents that can significantly reduce the attributable mortality and morbidity of sepsis. Developing novel therapeutic strategies to improve outcomes of sepsis remains an important focus of ongoing research in the field of critical care medicine. Apoptosis has recently been identified as an important mechanism of cell death and evidence suggests that prevention of cell apoptosis can improve survival in animal models of sepsis and endotoxaemia. In this review article, we summarise the critical role of apoptosis of the immune cells in the pathophysiology of sepsis and propose that blocking cell-signaling pathways leading to apoptosis may present a promising specific therapy for sepsis. Various methods to inhibit apoptosis including the cell surface Fas receptor pathway inhibitors, caspase inhibitors, over-expression of anti-apoptotic genes and small interfering ribonucleic acid therapy are discussed.
Incidence of Inferior Vena Cava Thrombosis Detected by Transthoracic Echocardiography in the Immediate Postoperative Period after Adult Cardiac and General Surgery
Authors: Saranteas T. , Kostopanag G. , Tzoufi M. , Drachtidi K. , Knox G. M. , Panou F.
Published: January 2019

Venous thromboembolism is an important complication after general and cardiac surgery. Using transthoracic echocardiography, this study assessed the incidence of inferior vena cava (IVC) thrombosis among a total of 395 and 289 cardiac surgical and major surgical patients in the immediate postoperative period after cardiac and major surgery, respectively. All transthoracic echocardiography was performed by a specialist intensivist within 24 hours after surgery with special emphasis on using the subcostal view in the supine position to visualise the IVC. Of the 395 cardiac surgical patients studied, the IVC was successfully visualised using the subcostal view in 315 patients (79.8%) and eight of these patients (2.5%) had a partially obstructive thrombosis in the IVC. In 250 out of 289 (85%) general surgical patients, the IVC was also clearly visualised, but only one patient (0.4%) had an IVC thrombosis (2.5 vs 0.4%, P <0.05). In summary, visualisation of the IVC was feasible in most patients in the immediate postoperative period after both adult cardiac and major surgery. IVC thrombosis appeared to be more common after adult cardiac surgery than general surgery. A large prospective cohort study is needed to define the risk factors for IVC thrombus and whether early thromboprophylaxis can reduce the incidence of IVC thrombus after adult cardiac surgery.
Low-Dose Epidural Dexmedetomidine Improves Thoracic Epidural Anaesthesia for Nephrectomy
Authors: Zeng X. Z. , Xu Y. M. , Cui X. G. , Guo Y. P. , Li W. Z.
Published: January 2019

Thoracic epidural anaesthesia alone is an applied technique of anaesthesia for nephrectomy which has both advantages and limitations. Dexmedetomidine is a highly selective α2-adrenoreceptor agonist which has both central and peripheral analgesic properties. Forty patients undergoing nephrectomy were enrolled in this clinical trial and allocated randomly to two groups, a control group (C group) and a dexmedetomidine group (D group). The C group received epidural 0.75% levobupivacaine 12 ml with 1 ml of isotonic sodium chloride solution, while the D group received epidural 0.75% levobupivacaine 12 ml with 1 ml (0.5 μg/kg) of dexmedetomidine. Haemodynamic changes, onset time and duration of sensory and motor block, muscle relaxation score, verbal rating score for pain, sedation score and the total postoperative analgesic consumption were evaluated. Sensory blockade duration was longer in the D group than in the C group ( P=0.01). The incidence of motor block and the muscle relaxation score were significantly higher in the D group compared with the C group ( P=0.01). Compared with the C group, pain scores were significantly lower in the first four postoperative hours in the D group (two hours rest P=0.038; two hours activity P=0.009; four hours rest P=0.044; four hours activity P=0.003). The total amount of flurbiprofen analgesic was significantly lower in the D group compared with the C group ( P=0.03). Epidural dexmedetomidine 0.5 μg/kg appears to intensify thoracic epidural anaesthesia with levobupivacaine.
Costs and Consequences: A Review of Discharge Opioid Prescribing for ongoing Management of Acute Pain
Authors: Macintyre P. E. , Huxtable C. A. , Flint S. L. P. , Dobbin M. D. H.
Published: January 2019

Over recent years there has been a growing need for patients to be sent home from hospital with prescribed opioids for ongoing management of their acute pain. Increasingly complex surgery is being performed on a day-stay or 23-hour-stay basis and inpatients after major surgery and trauma are now discharged at a much earlier stage than in the past. However, prescription of opioids to be self-administered at home is not without risk. In addition to the potential for acute adverse effects, including opioid-induced ventilatory impairment and impairment of driving skills, a review of the literature shows that opioid use continues in some patients for some years after surgery. There are also indications that over-prescription of discharge opioids occur with a significant amount not consumed, resulting in a potentially large pool of unused opioid available for later use by either the patient or others in the community. Concerns about the potential for harm arising from prescription of opioids for ongoing acute pain management after discharge are relatively recent. However, at a time when serious problems resulting from the non-medical use of opioids have reached epidemic proportions in the community, all doctors must be aware of the potential risks and be able to identify and appropriately manage patients where there might be a risk of prolonged opioid use or misuse. Anaesthetists are ideally placed to exercise stewardship over the use of opioids, so that these drugs can maintain their rightful place in the post-discharge analgesic pharmacopoeia.
The Clinical Trials Group Turns 20: A Clinician's Perspective
Authors: Duke G. J.
Published: January 2019

A clinician's perspective on the first 20 years of the Australian and New Zealand Intensive Care Society Clinical Trials Group and its influence on intensive care clinical practice over this same time period. This point of view discusses the importance of the Clinical Trials Group and the significance of several major published research trials.
Changing Patterns in Volatile Anaesthetic Agent Consumption over Seven Years in Victorian Public Hospitals
Authors: Weinberg L. , Tay S. , Aykanat V. , Segal R. , Tan C. O. , Peyton P. , Mcnicol L. , Story D. A.
Published: January 2019

Evidence-based choices of volatile agents can increase health cost efficiencies. In this pharmaco-economic study, we evaluated the trends and costs of volatile agent use in Australian public hospitals. The total number of volatile agent (isoflurane, sevoflurane and desflurane) bottles ordered and inflation-adjusted costs were collected from 65 Victorian public hospitals from 2005 to 2011. Environmental costs were measured through the 100-year global warming potential index as carbon dioxide equivalents. During this time period, the aggregate inflation-adjusted expenditure was $39,209,878. Time series analysis showed that bottles of isoflurane ordered decreased by 419/year (99% confidence interval [CI] −603 to −235); costs decreased by $56,017/year (99% CI -$93,243 to -$18,791). Bottles of sevoflurane increased by 1,330/year (99% CI 1141 to 1519); costs decreased by $423,3573/year (99% CI -$720,030 to -$112,783). Bottles of desflurane increased by 726/year (99% CI 288 to 1,164); costs increased by $171,578/year (99% CI $136,951 to $206,205). The amount of calculated greenhouse gas emissions released into the atmosphere over this period was 37,000 tonnes of carbon dioxide equivalents, with isoflurane contributing 6%, sevoflurane 17%, and desflurane 77% of this total. In conclusion, isoflurane is no longer being used in the majority of Victorian public hospitals, with sevoflurane and desflurane remaining as the primary volatile agents, utilised respectively at a ratio of 2.2 to 1, and costs at 0.8 to 1.
An Audit of the Statistical Validity of Conclusions of Clinical Superiority in Anaesthesia Journals
Authors: Gibbs N. M. , Weightman W. M.
Published: January 2019

Making a statistically valid conclusion of the superiority of a clinical intervention in a clinical trial requires not only a statistically significant P value, but also adequate a priori power and an observed effect size larger than the clinically important value specified in the sample size calculation. We scrutinised the five most highly cited clinical trials reporting one or more conclusions of clinical superiority published in Anesthesiology, the British Journal of Anaesthesia, Anaesthesia, Anesthesia and Analgesia and Anaesthesia and Intensive Care in 2011 or 2012 to determine how many met all three requisite criteria. In the 25 articles, there were a total of 36 unconditional conclusions of the superiority of a clinical intervention. All were supported by a statistically significant P value. However, only 15 (41.6%) met all three requisite statistical criteria to support clinical superiority. The remainder included secondary outcomes without specific reference to their observational nature, and primary outcomes whose observed effect size was smaller than the clinically important value specified in the sample size calculation. These findings indicate that clinicians should closely scrutinise conclusions of clinical superiority in anaesthesia journals. Many will be ‘hypothesis-generating observations’ without adequate statistical support for a conclusion of clinical superiority in their own right.
Inter-Rater Reliability of the ASA Physical Status Classification in a Sample of Anaesthetists in Western Australia
Authors: Riley R. H. , Holman C. D. J. , Fletcher D. R.
Published: January 2019

The American Society of Anesthesiologists (ASA) scale is a widely used six-point ordinal scale that allows anaesthetists to assign a risk score to each patient scheduled for anaesthesia. Earlier studies of inter-rater reliability in assigning ASA physical status classifications to a standard set of patient descriptions have shown modest agreement. We surveyed 401 anaesthetists practising in Western Australia using descriptions of clinical history, physical examination and investigation results of ten hypothetical adult patients, pre-designed by other researchers, to have ASA class ranging 1 through 5. Anaesthetist respondents were also asked to supply their age, level of training (trainee or faculty) and sex and to indicate whether their training was undertaken mainly in Australia or New Zealand or elsewhere. The Kappa statistic (chance-corrected measure of agreement) was calculated for ten observations by all raters. Responses were received from 151 anaesthetists (response rate 38%); 64% male, 25% trainees; mean age 42 years, range 26 to 68 years; 83% trained in Australia or New Zealand. Calculated Kappa was 0.40. ASA class 2 was identified correctly least frequently and ASA class 1 was identified correctly most often. Correctly identifying ASA class was not related to age, level of training, sex or training region. We found only fair agreement among anaesthetists in assigning ASA class to ten fictitious patients, which was no better than that observed in earlier studies. Further, the range of scores assigned to standard patients’ histories by anaesthetists supports earlier concerns about the robustness of this classification.
Anaesthesia-Related Haemodynamic Complications in Williams Syndrome Patients: A Review of One Institution's Experience
Authors: Olsen M. , Fahy C. J. , Costi D. A. , Kelly A. J. , Burgoyne L. L.
Published: January 2019

Williams syndrome is a genetic disorder associated with cardiac pathology, including supravalvular aortic stenosis and coronary artery stenosis. Sudden cardiac death has been reported in the perioperative period and attributed to cardiovascular pathology. In this retrospective audit, case note and anaesthetic records were reviewed for all confirmed Williams syndrome patients who had received an anaesthetic in our institution between July 1974 and November 2009. There were a total of 108 anaesthetics administered in 29 patients. Twelve of the anaesthetics (11.1%) were associated with cardiac complications including cardiac arrest in two cases (1.85%). Of the two cardiac arrests, one patient died within the first 24 hours postanaesthetic and the other patient survived, giving an overall mortality of 0.9% (3.4%). We conclude that Williams syndrome confers a significant anaesthetic risk, which should be recognised and considered by clinicians planning procedures requiring general anaesthesia.
Adequate Images in Intraoperative Transoesophageal Echocardiography: A Quality Improvement Project
Authors: Graham J. M. , Sidebotham D. , Story D. A. , Hu R. , Parker F.
Published: January 2019

A suggested standard examination (SSE) for intraoperative transoesophageal echocardiography for cardiac surgery was developed at the Green Lane Department of Cardiothoracic and Otorhinolaryngology Anaesthesia at the Auckland City Hospital. The examination includes views to be recorded in all patients pre- and post-cardiopulmonary bypass. There are also additional views to be recorded in patients with valvular pathology. Using the SQUIRE (Standards for Quality Improvement Reporting Excellence) guidelines, we report an audit comparing acquisition ratios before and after introduction of the SSE. A baseline mean acquisition ratio of 0.62 was achieved, which was not significantly changed by the introduction of the SSE. Nevertheless, we found the SSE to be a useful audit tool and believe it might be of interest to others to assist with perioperative transoesophageal echocardiography quality assurance and education.
Use of the Trauma Embolic Scoring System (TESS) to Predict Symptomatic Deep Vein Thrombosis and Fatal and Non-Fatal Pulmonary Embolism in Severely Injured Patients
Authors: Ho K. M. , Rao S. , Rittenhouse K. J. , Rogers F. B.
Published: January 2019

Fatal pulmonary embolism is the third most common cause of death after major trauma. We hypothesised that the Trauma Embolic Scoring System (TESS) would have adequate calibration and discrimination in a group of severely injured trauma patients in predicting venous thromboembolism (VTE), and could be used to predict fatal and non-fatal symptomatic pulmonary embolism. Calibration and discrimination of the TESS were assessed by the slope and intercept of the calibration curve and the area under the receiver operating characteristic curve, respectively. Of the 357 patients included in the study, 74 patients (21%) developed symptomatic VTE after a median period of 14 days following injury. The TESS predicted risks of VTE were higher among patients who developed VTE than those who did not (14 versus 9%, P=0.001) and had a moderate ability to discriminate between patients who developed VTE and those who did not (area under the receiver operating characteristic curve 0.71, 95% confidence interval 0.65 to 0.77). The slope and intercept of the calibration curve were 2.76 and 0.34, respectively, suggesting that the predicted risks of VTE were not sufficiently extreme and overall, underestimated the observed risks of VTE. Using 5% predicted risk of VTE as an arbitrary cut-point, TESS had a high sensitivity and negative predictive value (both ≥0.97) in excluding fatal and non-fatal pulmonary embolism. In summary, the TESS had a reasonable ability to discriminate between patients who developed VTE and those who did not and may be useful to select different preventive strategies to prevent VTE in severely injured patients.
A Mobile Telephone-Based SMS and Internet Survey System for Self-Assessment in Australian Anaesthesia: Experience of a Single Practitioner
Authors: Belavy D.
Published: January 2019

Self-assessment and audit in anaesthesia require a systematic approach to postoperative data collection. The increasing prevalence of mobile internet technology offers a new data collection method for anaesthetists. In this paper, a system for mobile internet data collection is described and the preliminary experience with its use is presented. The system was developed by the author and combined an open source survey application and a short message service (SMS) gateway to send SMS messages to patients after their anaesthesia and surgery. The messages requested patients to complete an online Quality of Recovery survey questionnaire if they had a smartphone. The results were immediately available. A preliminary survey of consenting patients with available mobile telephone numbers in a private practice was undertaken by the author. A total of 123 procedures were eligible for follow-up and survey requests were sent to 94 patients. Sixty-five surveys were completed. This represents 69% of surveys requested, demonstrating that mobile phone technology can be used to provide significant amounts of data for quality assurance. However, the implementation of a mobile internet data collection system requires consideration of privacy principles, security and ethical handling of data.
Sugammadex: What do we Know and What do we Still Need to Know? A Review of the Recent (2013 to 2014) Literature
Authors: Ledowski T.
Published: January 2019

Since its launch in 2008, sugammadex has been considered one of the most significant developments in anaesthesia-related pharmacology. With almost 500 sugammadex-related publications and over nine million patient exposures worldwide, user experience and scientific data have grown exponentially. However, several important questions are yet to be answered. This article reviews the sugammadex-related literature in 2013 and 2014 to determine which of these questions have been answered more fully over the last 18 months and which questions require more information and research.
Impact of Conversion from an Open Ward Design Paediatric Intensive Care Unit Environment to All Isolated Rooms Environment on Incidence of Bloodstream Infections and Antibiotic Resistance in Southern Israel (2000 to 2008)
Authors: Lazar I. , Abukaf H. , Sofer S. , Peled N. , Leibovitz E.
Published: January 2019

We studied the epidemiology, microbiology, clinical aspects and outcome of bloodstream infections (BSI) in a tertiary paediatric intensive care unit. All BSI episodes were prospectively identified and analysed. The paediatric intensive care unit moved in 2006 from an open-plan unit to a new (all single room) unit. Three hundred and fifty-three BSI episodes occurred in 299 of 4162 patients. Overall, BSI incidence was 85 per 1000 hospitalised children. Fewer BSI episodes occurred during the last two years of the study (2007 to 2008), compared with 2000 to 2006 (70 of 1061 admissions, 6.5% versus 283 of 3101 admissions, 9.1%, respectively, P=0.01). There were 127 of 340 (37.4%) community-acquired and 213 of 340 (62.6%) nosocomial BSI episodes (31 of 1000 and 51 of 1000, respectively). Nosocomial BSI episodes decreased during 2007 to 2008 versus 2000 to 2006 (37.7% versus 55.8%, P=0.03). In 448 instances, pathogens were isolated, 231 (52%) Gram-positive and 188 (42%) Gram-negative. Coagulase-negative Staphylococci, S. pneumoniae and S. aureus (41.1%, 19.9% and 11.7%, respectively) were the most common Gram-positive and Enterobacteriaceae spp. the most frequent Gram-negative organisms (45.2%, of them Klebsiella spp. and E. coli 40% and 29.4%, respectively). A significant decrease was recorded during 2007 to 2008 in Enterobacteriaceae resistance to piperacillin, gentamicin and ciprofloxacin. Thirty of 299 (10%, 9 with S. pneumoniae-BSI) patients died. A significant decrease in BSI and nosocomial incidence and Enterobacteriaceae spp. antibiotic resistance was recorded following the conversion of the paediatric intensive care unit from an open ward to an all isolated rooms environment.
The Effect of Mechanical Ventilator Settings during Ventilator Hyperinflation Techniques: A Bench-Top Analysis
Authors: Thomas P. J.
Published: January 2019

Ventilator hyperinflations are used by physiotherapists for the purpose of airway clearance in intensive care. There is limited data to guide the selection of mechanical ventilator modes and settings that may achieve desired flow patterns for ventilator hyperinflation. A mechanical ventilator was connected to two lung simulators and a respiratory mechanics monitor. Peak inspiratory (PIFR) and expiratory flow rates (PEFR) were measured during manipulation of ventilator modes (pressure support ventilation [PSV], volume-controlled synchronised intermittent mandatory ventilation [VC-SIMV] and pressure-controlled synchronised intermittent mandatory ventilation [PC-SIMV]) and ventilator settings (including set tidal volume, positive end-expiratory pressure, inspiratory flow rate, inspiratory pause, pressure support, inspiratory time and/or inflation pressure). Additionally, each trial was conducted with high (0.05 l/cmH2O) and low (0.01 l/cmH2O) compliance settings on the lung simulators. Each trial was dichotomised into success or failure under three categories (attainment of PIFR/PEFR less than or equal to 0.9, PEFR-PIFR greater than 17 l/min, PEFR greater than or equal to 40 l/min). A total of 232 trials were conducted (96 VC-SIMV, 96 PC-SIMV, 40 PSV). A greater proportion of VC-SIMV trials were ceased due to high peak inspiratory pressures (35%). However, VC-SIMV trials were more likely to be successful at meeting all three outcome measures (26 VC-SIMV trials, 7 PC-SIMV trials, 0 PSV trials). It was found that manipulation of settings in VC-SIMV mode appears more successful than PSV and PC-SIMV for ventilator hyperinflations.
Intensive Care Unit Research Ethics and Trials on Unconscious Patients
Authors: Gillett G. R.
Published: January 2019

There are widely acknowledged ethical issues in enrolling unconscious patients in research trials, particularly in intensive care unit (ICU) settings. An analysis of those issues shows that, by and large, patients are better served in units where research is actively taking place for several reasons: i) they do not fall prey to therapeutic prejudices without clear evidential support, ii) they get a chance of accessing new and potentially beneficial treatments, iii) a climate of careful monitoring of patients and their clinical progress is necessary for good clinical research and affects the care of all patients and iv) even those not in the treatment arm of a trial of a new intervention must receive best current standard care (according to international evidence-based treatment guidelines). Given that we have discovered a number of ‘best practice’ regimens of care that do not optimise outcomes in ICU settings, it is of great benefit to all patients (including those participating in research) that we are constantly updating and evaluating what we do. Therefore, the practice of ICU-based clinical research on patients, many of whom cannot give prospective informed consent, ticks all the ethical boxes and ought to be encouraged in our health system. It is very important that the evaluation of protocols for ICU research should not overlook obvious (albeit probabilistic) benefits to patients and the acceptability of responsible clinicians entering patients into well-designed trials, even though the ICU setting does not and cannot conform to typical informed consent procedures and requirements.
Consent for Labour Epidural Analgesia: An Observational Study in a Single Institution
Authors: Trumble J. , Lee J. , Slater P. M. , Sellors J. , Cyna A. M.
Published: January 2019

There is a wide range of practice amongst obstetric anaesthetists when obtaining consent for women requesting labour epidural analgesia. This is the first prospective observational study recording the number and types of risks mentioned and whether the risk was quantified. Statements of benefits and alternatives to the procedure were also noted. Fourteen anaesthetists, each consulting a single patient, were recorded during the process of obtaining consent and inserting the epidural. The most commonly mentioned risks (median 7) were headache/dural puncture, failure/difficulty with insertion, nerve damage, bleeding/haematoma and infection/epidural abscess. There was no difference between consultants and trainees, although consultants showed greater variance. It was uncommon for anaesthetists to state a benefit (21%) or mention an alternative option (21%), but there was usually a quantitative statement of risk (71%). Data showed a deviation from the Australian and New Zealand College of Anaesthetists guidelines and these findings may encourage anaesthetists to reflect on their own practice and guide future research.