bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Cardiac Output Measurements in Critically Ill Patients: Flotrac/Vigileo Vs Transthoracic Doppler Echocardiography
Authors: Mclean A. S. , Huang S. J. , Kot M. , Rajamani A. , Hoyling L.
Published: January 2019

Measurement of cardiac output is an integral part of patient management in the intensive care unit. FloTrac/Vigileo is a continuous cardiac output monitoring device that does not need re-calibration. However, its reliability has been questioned in some studies, especially involving surgical patients. In this study, we evaluated the comparability of FloTrac/Vigileo and transthoracic Doppler echocardiography in 53 critically ill patients requiring continuous cardiac output monitoring. Most of these patients had septic or cardiogenic shock. Cardiac output was measured by both FloTrac/Vigileo and transthoracic Doppler echocardiography. The bias and precision (mean and SD) between the two devices was 0.35±1.35 l/minute. The limits of agreement were -2.3 to 3.0 l/minute (%error=49.3%). When patients with irregular heart rhythms and aortic stenosis were excluded, the bias and precision was 0.02±0.80 l/minute (n=42). The limits of agreement were -1.55 to 1.59 l/minute (%error=29.5%). Patient demographics (body surface area, gender and age) did not affect the bias, but there was a mild tendency for FloTrac/Vigileo to register a higher cardiac output at high heart rates. Changes in cardiac output for two consecutive days correlated well between the two methods (r=0.86; P <0.001). In summary, with the exceptions of patients with irregular heart rhythms and significant aortic stenosis, FloTrac/Vigileo is clinically comparable to transthoracic Doppler echocardiography in cardiac output measurements in critically ill patients.
Ciprofloxacin in Critically Ill Children
Authors: Sideri G. , Kafetzis D. A. , Vouloumanou E. K. , Papadatos J. H. , Papadimitriou M. , Falagas M. E.
Published: January 2019

Data regarding the use of fluoroquinolones in critically ill children are scarce. We present our experience regarding the use of ciprofloxacin in this specific patient population. We prospectively identified all paediatric patients who received ciprofloxacin treatment in the intensive care unit of the tertiary care P. & A. Kyriakou Children's Hospital during a three year period (2005 to 2008). Eighteen paediatric patients (mean age 23 months, 12 females) who received intravenous ciprofloxacin were identified. Various underlying diseases, including malignancy and immunodeficiency, were observed. None of the evaluated patients had cystic fibrosis. Fourteen patients had bacteraemia (mainly caused from Gram-negative pathogens), one had Stenotrophomonas maltophilia pneumonia, while no pathogen was identified in three patients. The latter patients received ciprofloxacin due to the severity of their clinical manifestations. All patients with microbiologically documented infections recovered. Three deaths attributed to the underlying diseases were noted. Within a 10-day follow-up, two cases of diarrhoea, one case of vomiting and one case of reversible supraventricular tachycardia were noted. No case of QT prolongation was noted. The short-term follow-up hampered any assessment of joint and cartilage toxicity, potentially associated with ciprofloxacin treatment. Our study suggests that ciprofloxacin may be a useful option for critically ill children without cystic fibrosis. Even though firm conclusions regarding the safety profile of ciprofloxacin in critically ill children could not be drawn, our study provides useful information regarding short-term adverse events associated with ciprofloxacin.
The Influence of Objective Prognostic Information on the Likelihood of Informed Consent for Decompressive Craniectomy: A Study of Australian Anaesthetists
Authors: Honeybul S. , O'Hanlon S. , Ho K. M. , Gillett G.
Published: January 2019

The aim of this study was to assess the influence of detailed prognostic information on the likelihood of informed consent for decompressive craniectomy for severe traumatic brain injury. The study was a simulation exercise, asking anaesthetists to give opinions as if they themselves were the injured party. Anaesthetists were chosen as they represent a distinct group likely to be familiar with the procedure and the decision-making process, but not necessarily aware of the longer-term outcomes.

A two-part structured interview was used. Seventy-five anaesthetists were shown three cases of differing severity of traumatic brain injury. A visual analogue scale (1 to 10) was used to assess the strengths of their opinion. Initially they were asked their opinion with no predictive outcome data. They were then shown the prediction of an unfavourable outcome (Glasgow Outcome Scale severely disabled, vegetative state or dead) and the observed outcome at 18-month follow-up from a cohort of 147 patients (who had had a decompressive craniectomy for severe traumatic brain injury in Perth, Western Australia between the years 2004 and 2008). The opinions of the participants before and after seeing the prediction outcome data were compared. The participants’ preferences to consent to the procedure changed after being informed of the predicted risks of unfavourable outcomes (P values <0.01). The changes in attitude appeared to be independent of age group, amount of experience in caring for similar patients and religious background. These findings suggest that access to objective information on risks of unfavourable outcomes may influence opinions in relation to consent for decompressive craniectomy for traumatic brain injury.
Acute Pain Management in Opioid-Tolerant Patients: A Growing Challenge
Authors: Huxtable C. A. , Roberts L. J. , Somogyi A. A. , Macintyre P. E.
Published: January 2019

In Australia and New Zealand, in parallel with other developed countries, the number of patients prescribed opioids on a long-term basis has grown rapidly over the last decade. The burden of chronic pain is more widely recognised and there has been an increase in the use of opioids for both cancer and non-cancer indications. While the prevalence of illicit opioid use has remained relatively stable, the diversion and abuse of prescription opioids has escalated, as has the number of individuals receiving methadone or buprenorphine pharmacotherapy for opioid addiction. As a result, the proportion of opioid-tolerant patients requiring acute pain management has increased, often presenting clinicians with greater challenges than those faced when treating the opioid-naïve.

Treatment aims include effective relief of acute pain, prevention of drug withdrawal, assistance with any related social, psychiatric and behavioural issues, and ensuring continuity of long-term care. Pharmacological approaches incorporate the continuation of usual medications (or equivalent), short-term use of sometimes much higher than average doses of additional opioid, and prescription of non-opioid and adjuvant drugs, aiming to improve pain relief and attenuate opioid tolerance and/or opioid-induced hyperalgesia. Discharge planning should commence at an early stage and may involve the use of a ‘Reverse Pain Ladder’ aiming to limit duration of additional opioid use. Legislative requirements may restrict which drugs can be prescribed at the time of hospital discharge. At all stages, there should be appropriate and regular consultation and liaison with the patient, other treating teams and specialist services.
Experience with High Frequency Oscillation Ventilation during the 2009 H1N1 Influenza Pandemic in Australia and New Zealand
Authors: Boots R. J. , Lipman J. , Lassig-Smith M. , Stephens D. P. , Thomas J. , Shehabi Y. , Bass F. , Anthony A. , Long D. , Seppelt I. M. , Weisbrodt L. , Erickson S. , Beca J. , Sherring C. , Mcguiness S. , Parke R. , Stachowski E. R. , Boyd R. , Howe B.
Published: January 2019

During the 2009 H1N1 pandemic, large numbers of patients had severe respiratory failure. High frequency oscillation ventilation was used as a salvage technique for profound hypoxaemia. Our aim was to compare this experience with high frequency oscillation ventilation during the 2009 H1N1 pandemic with the same period in 2008 by performing a three-month period prevalence study in Australian and New Zealand intensive care units. The main study end-points were clinical demographics, care delivery and survival. Nine intensive care units contributed data. During 2009 there were 22 H1N1 patients (17 adults, five children) and 10 non-H1N1 patients (five adults, five children), while in 2008, 18 patients (two adults, 16 children) received high frequency oscillation ventilation. The principal non-H1N1 high frequency oscillation ventilation indication was bacterial or viral pneumonia (56%). For H1N1 patients, the median duration of high frequency oscillation ventilation was 3.7 days (interquartile range 1.8 to 5) with concomitant therapies including recruitment manoeuvres (22%), prone ventilation (41%), inhaled prostacyclins (18%) and inhaled nitric oxide (36%). Seven patients received extracorporeal membrane oxygenation, six having H1N1. Three patients had extracorporeal membrane oxygenation concurrently, two as salvage therapy following the commencement of high frequency oscillation ventilation. In 2008, no high frequency oscillation ventilation patient received extracorporeal membrane oxygenation. Overall hospital survival was 77% in H1N1 patients, while survival in patients having adjunctive extracorporeal membrane oxygenation was similar to those receiving high frequency oscillation ventilation alone (65% compared to 71%, P=1.00). Survival rates were comparable to published extracorporeal membrane oxygenation outcomes. high frequency oscillation ventilation was used successfully as a rescue therapy for severe respiratory failure. high frequency oscillation ventilation was only available in a limited number of intensive care units during the H1N1 pandemic.
The Association between Intraoperative Electroencephalogram-Based Measures and Pain Severity in the Post-Anaesthesia Care Unit
Authors: Law C. J. , Sleigh J. W. , Barnard J. P. M. , Maccoll J. N.
Published: January 2019

This observational study aimed to identify simple electroencephalogram indices of inadequate intraoperative opioid-mediated nociceptive blockade and to compare these indices with routinely used clinical predictors of severe postoperative pain in adults. Intraoperative trend and waveform data (electrocardiogram, pulse oximetry and electroencephalogram) were collected, pain intensity in the post-anaesthesia care unit was quantified using an 11-point Verbal Rating Score, and opioid administration was recorded. Using the initial post-anaesthesia care unit Verbal Rating Score as the primary endpoint, the relationship between five possible explanatory variables – surgery type, depth of volatile anaesthesia (minimum alveolar concentration), electroencephalogram signs (state entropy, spindle-like activity and delta-band power) and estimated end-of-operation effect-site morphine concentrations – was examined. One hundred and thirteen patients were recruited, with 94 included in the final clinical and electroencephalogram data analysis. Fifty-two patients had moderate or severe pain (Verbal Rating Score >5). State entropy was lower (46.5±2.9 vs 43.1±1.9, P=0.04) and spindle-like activity higher (0.42±0.03 vs 0.50±0.02, P=0.03) in the moderate/severe pain group. These findings suggest that there is a modest association between electroencephalogram measures near the end of surgery and the severity of postoperative pain.
Prophylactic Use of Midazolam or Propofol at the End of Surgery May Reduce the Incidence of Emergence Agitation after Sevoflurane Anaesthesia
Authors: Kim Y. H. , Yoon S. Z. , Lim H. J. , Yoon S. M.
Published: January 2019

Sevoflurane is associated with a high incidence of emergence agitation in children. Midazolam and propofol have been examined with the aim of reducing emergence agitation after sevoflurane anaesthesia. However, the effect of both drugs on emergence agitation is still controversial. Therefore we designed this study to measure the effect of midazolam or propofol at the end of surgery on emergence agitation during the recovery period.

One hundred and one children, aged one to 13 years, undergoing strabismus surgery were enrolled in this randomised double-blind study. Anaesthesia was induced and maintained with sevoflurane in N2O/O2. Children were randomly assigned to receive midazolam 0.05 mg/kg (group M, n=35), propofol 1 mg/kg (group P, n=31) or saline (group S, n=35). A four-point scale was used to evaluate recovery characteristics upon awakening and during the first hour after emergence from anaesthesia.

The incidence of emergence agitation in group M was 42.9% (15/35), in group P 48.4% (15/31) and in group S 74.3% (26/35). The incidence of emergence agitation in groups M and P was significantly less than in group S. The emergence time was prolonged for patients in groups M and P compared to group S. There was no significant difference in the incidence of emergence agitation or in emergence times between the groups P and M.

We conclude that propofol or midazolam administration before the end of surgery may be effective in reducing the incidence of emergence agitation in children undergoing strabismus surgery under sevoflurane anaesthesia.
Single Level Paravertebral versus Caudal Block in Paediatric Inguinal Surgery
Authors: Tug R. , Ozcengiz D. , Güneş Y.
Published: January 2019

Paravertebral block (PVB) has been used for postoperative analgesia in children since 1992. There are no prospective randomised studies comparing the use of PVB versus caudal block (CB) for outpatient inguinal hernia repair surgery. The hypothesis of this study is that a single level, single injection PVB can provide a longer duration of analgesia and less requirement for supplemental analgesia than single shot CB for children undergoing inguinal surgery.

Seventy children, aged three to seven, American Society of Anesthesiologists score I to II, having unilateral inguinal surgery were enrolled in the study. The patients were divided into two randomised groups. In group PVB, a single shot of 0.2 ml/kg levobupivacaine was administered via the lumbar paravertebral route and in group CB, patients were given 1 ml/kg levobupivacaine caudally. Sevoflurane concentration was evaluated after induction and recorded during incision, sac traction and closure. Face, legs, activity, cry and consolability (FLACC) scores, heart rate, blood pressure and SpO2 were evaluated postoperatively.

Only four (11.4 %) patients in the PVB group needed rescue analgesic drugs compared to 12 (34.3%) patients in the CB group (P=0.044). Patients were given tramadol as rescue analgesia in the first four postoperative hours. No other supplemental analgesic drug was given apart from tramadol. FLACC scores were the same in the both groups. Parental satisfaction was significantly higher in the PVB group compared to the CB group (74.3 vs 40%, P=0.01).

This study has demonstrated that a single level single injection paravertebral block provides superior intraoperative and postoperative analgesia when compared to a caudal block for unilateral inguinal hernia repair.
‘Safe’ Methaemoglobin Concentrations are a Mortality Risk Factor in Patients Receiving Inhaled Nitric Oxide
Authors: Rolley L. , Bandeshe H. , Boots R. J.
Published: January 2019

Inhaled nitric oxide (iNO) can reduce pulmonary arterial hypertension and improve oxygenation in some patients with severe respiratory or heart failure. Despite this, iNO has not been found to improve survival.

This study aimed to perform a local practice audit to assess the mortality predictors of critically ill patients who had received iNO as therapy for pulmonary hypertension and respiratory or heart failure. A retrospective audit in a single tertiary centre intensive care unit of patients receiving iNO was conducted between 2004 and 2009. The indications for iNO use, comorbidities, severity of illness, organ function, oxygenation, Sequential Organ Failure Assessment scores, patterns of iNO use, adverse events and outcomes were reviewed.

In 215 patients receiving iNO, improvement in oxygenation after one hour from iNO commencement did not predict either intensive care unit (P=0.36) or hospital (P=0.72) mortality. The independent risk factors for intensive care unit mortality were worsening Sequential Organ Failure Assessment scores within 24 hours of commencing iNO (adjusted odds ratio 1.07, 95% confidence interval 1.05 to 1.18), the Charlson Comorbidity Score (adjusted odds ratio 1.49, 95% confidence interval 1.16 to 1.91) and the peak methaemoglobin concentration in arterial blood while receiving iNO (adjusted odds ratio 2.67, 95% confidence interval 1.42 to 4.96).

Inhaled nitric oxide as salvage therapy for severe respiratory failure in critically ill patients is not routinely justified. Increased methaemoglobin concentration during iNO therapy, even when predominantly less than 3%, is associated with increased mortality.
Anaesthetic Management of Emergency Caesarean Section in a Patient with Seizures and Likely Raised Intracranial Pressure Due to Tuberculous Meningitis
Authors: Baidya D. K. , Trikha A. , Menon S. , Garg R.
Published: January 2019

We report the anaesthetic management of a term pregnant woman with active tuberculous meningitis, who had experienced seizures, had signs of raised intracranial pressure and required emergency caesarean section. Peripartum anaesthetic management of a patient with tuberculous meningitis is a rare event.
A Comparison of Three Minimally Invasive Cardiac Output Devices with Thermodilution in Elective Cardiac Surgery
Authors: Phan T. D. , Kluger R. , Wan C. , Wong D. , Padayachee A.
Published: January 2019

This study compared the cardiac output responses to haemodynamic interventions as measured by three minimally invasive monitors (Oesophageal Doppler Monitor, the VigileoFlotrac and the LiDCOrapid) to the responses measured concurrently using thermodilution, in cardiac surgical patients. The study also assessed the precision and bias of these monitors in relation to thermodilution measurements.

After a fluid bolus of at least 250 ml, the measured change in cardiac output was different among the devices, showing an increase with thermodilution in 82% of measurements, Oesophageal Doppler Monitor 68%, VigileoFlotrac 57% and LiDCOrapid 41%. When comparing the test devices to thermodilution, the kappa statistic showed at best only fair agreement, Oesophageal Doppler Monitor 0.34, LiDCOrapid 0.28 and VigileoFlotrac -0.03. After vasopressor administration, there was also significant variation in the change in cardiac output measured by the devices. Using Bland-Altman analysis, the precision of the devices in comparison to thermodilution showed minimal bias, but wide limits of agreement with percentage errors of Oesophageal Doppler Monitor 64.5%, VigileoFlotrac 47.6% and LiDCOrapid 54.2%. These findings indicate that these three devices differ in their responses, do not always provide the same information as thermodilution and should not be used interchangeably to track cardiac output changes.
Comparison of Fluid Compartments and Fluid Responsiveness in Septic and Non-Septic Patients
Authors: Sánchez M. , Jiménez-Lendínez M. , Cidoncha M. , Asensio M. J. , Herrero E. , Collado A. , Santacruz M.
Published: January 2019

Our objective was to study the response to a fluid load in patients with and without septic shock, the relationship between the response and baseline fluid distributions and the ratios of the various compartments.

A total of 18 patients with septic shock and 14 control patients without pathologies that increase capillary permeability were evaluated prospectively. We used transpulmonary thermodilution to measure the extravascular lung water index, intrathoracic blood volume index and pulmonary blood volume. For the measurement of the initial distribution volume of glucose, plasma volume and extracellular water, we used dilutions of glucose, indocyanine green and sinistrin respectively. Transpulmonary thermodilution and dilutions of glucose were repeated 75 minutes after the beginning of the fluid load.The patients in the septic group had higher volumes of extracellular water (median 295 vs 234 ml/kg, P <0.001), lower intrathoracic blood volume index (median 894 vs 1157 ml/m2, P <0.003), higher pulmonary permeability ratios (extravascular lung water/pulmonary blood volume) (P <0.003) and higher systemic permeability ratios (interstitial/plasma volume) (P <0.04). The intrathoracic blood volume index increase after fluid loading was lower in the septic group (10 vs 145 ml/m2). The pulmonary permeability ratios did not correlate with the systemic permeability ratios, and in the septic group, the percentage volume retained in the intrathoracic blood volumes after fluid loading did not correlate with the systemic permeability ratios. Septic shock can cause a redistribution of fluids. Fluid administration in these patients produced a minimal increase in intrathoracic blood volume, and the percentage of volume retained in this space was not correlated with the interstitial/plasma volume ratio.
Optimal Dose of Vancomycin for Treating Methicillin-Resistant Staphylococcus Aureus Pneumonia in Critically Ill Patients
Authors: Chung J. , Oh J. M. , Cho E. M. , Jang H. J. , Hong S. B. , Lim C. M. , Koh Y. S.
Published: January 2019

A prospective cohort study was performed to determine the optimal dose of vancomycin to maintain a serum trough concentration of at least 15 to 20 mg/l and to assess the efficacy of this target vancomycin concentration in the treatment of methicillin-resistant Staphylococcus aureus pneumonia. Vancomycin pharmacokinetic parameters were estimated using a CAPSIL software program from serum concentrations of 141 patients with pneumonia treated with vancomycin, regardless of methicillin-resistant Staphylococcus aureus status, at a 28-bed medical intensive care unit. Vancomycin trough concentrations and other pharmacokinetic parameters were compared between five groups of patients differing in their renal function: 1) creatinine clearance >60 ml/minute, 2) creatinine clearance 30 to 60 ml/minute, 3) creatinine clearance <30 ml/minute, 4) on intermittent haemodialysis, and 5) on continuous renal replacement therapy. More than 70% of patients failed to reach the recommended therapeutic serum trough concentrations: a higher dose of vancomycin is necessary to maintain serum trough concentration at 15 to 20 mg/l, particularly in critically ill patients with creatinine clearance above 60 ml/minute and in those on intermittent haemodialysis. Among patients with methicillin-resistant Staphylococcus aureus pneumonia, no significant differences were observed in the treatment success rate, length of intensive care unit stay, and intensive care unit mortality rate between patients with vancomycin trough concentrations of >20 mg/l, 15 to 20 mg/l and <15 mg/l.
Relationship between Intracranial Pressure Monitoring and Outcomes in Severe Traumatic Brain Injury Patients
Authors: Haddad S. , Aldawood A. S. , Alferayan A. , Russell N. A. , Tamim H. M. , Arabi Y. M.
Published: January 2019

Intracranial pressure (ICP) monitoring is recommended in patients with a severe traumatic brain injury (TBI) and an abnormal computed tomography (CT) scan. However, there is contradicting evidence about whether ICP monitoring improves outcome. The purpose of this study was to examine the relationship between ICP monitoring and outcomes in patients with severe TBI. From February 2001 to December 2008, a total of 477 consecutive adult (>18 years) patients with severe TBI were included retrospectively in the study. Patients who underwent ICP monitoring (n=52) were compared with those who did not (n=425). The primary outcome was hospital mortality. Secondary outcomes were ICU mortality, mechanical ventilation duration, the need for tracheostomy, and ICU and hospital length of stay (LOS). After adjustment for multiple potential confounding factors, ICP monitoring was not associated with significant difference in hospital or ICU mortality (odds ratio [OR]=1.71, 95% confidence interval [CI]=0.79 to 3.70, P=0.17; OR=1.01, 95% CI=0.41 to 2.45, P=0.99, respectively). ICP monitoring was associated with a significant increase in mechanical ventilation duration (coefficient=5.66, 95% CI=3.45 to 7.88, P <0.0001), need for tracheostomy (OR=2.02, 95% CI=1.02 to 4.03, P=0.04), and ICU LOS (coefficient=5.62, 95% CI=3.27 to 7.98, P <0.0001), with no significant difference in hospital LOS (coefficient=8.32, 95% CI=-82.6 to 99.25, P=0.86). Stratified by the Glasgow Coma Scale score, ICP monitoring was associated with a significant increase in hospital mortality in the group of patients with Glasgow Coma Scale 7 to 8 (adjusted OR=12.89, 95% CI=3.14 to 52.95, P=0.0004). In patients with severe TBI, ICP monitoring was not associated with reduced hospital mortality, however, with a significant increase in mechanical ventilation duration, need for tracheostomy, and ICU LOS.
A Randomised Controlled Trial of Pharmacist Medication Histories and Supplementary Prescribing on Medication Errors in Postoperative Medications
Authors: Marotti S. B. , Kerridge R. K. , Grimer M. D.
Published: January 2019

Errors in the management of regular medications at the time of hospital admission are common. This randomised controlled three-arm parallel-group trial examined the impact of pharmacist medication history taking and pharmacist supplementary prescribing on unintentional omissions of postoperative medications in a large perioperative service. Participants included elective surgical patients taking regular medications with a postoperative hospital stay of one night or more. Patients were randomly assigned, on admission, to usual care (n=120), a pharmacist medication history only (n=120) or pharmacist medication history and supplementary prescribing (n=120). A medication history involved the pharmacist interviewing the patient preoperatively and documenting a medication history in the medical record. In the supplementary prescribing group the patients’ regular medicines were also prescribed on the inpatient medication chart by the pharmacist, so that dosing could proceed as soon as possible after surgery without the need to wait for medical review. The estimate marginal mean number of missed doses during a patients hospital stay was 1.07 in the pharmacist supplementary prescribing group, which was significantly less than both the pharmacist history group (3.30) and the control group (3.21) (P <0.001). The number of medications charted at an incorrect dose or frequency was significantly reduced in the pharmacist history group and further reduced in the prescribing group (P <0.001). We conclude that many patients miss doses of regular medication during their hospital stay and preoperative medication history taking and supplementary prescribing by a pharmacist can reduce this.
Evaluating Sleep Characteristics in Intensive Care Unit and Non-Intensive Care Unit Physicians
Authors: Ok G. , Yilmaz H. , Tok D. , Erbüyün K. , Çoban S. , Dinç G.
Published: January 2019

Healthcare workers’ cognitive performances and alertness are highly vulnerable to sleep loss and circadian rhythms. The purpose of this study was to investigate the changes in sleep characteristics of intensive care unit (ICU) and non-ICU physicians. Actigraphic sleep parameters, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale and Hamilton Depression Rating Scale were evaluated for ICU and non-ICU physicians on the day before shift-work and on three consecutive days after shift-work. Total sleep time, sleep latency, wakefulness after sleep onset, total activity score, movement fragmentation index, sleep efficiency, daytime naps and total nap duration were also calculated by actigraph. In the ICU physicians, the mean Pittsburgh Sleep Quality Index score was significantly higher than the non-ICU physicians (P=0.001), however mean Epworth Sleepiness Scale scores were not found significantly different between the two groups. None of the scores for objective sleep parameters were statistically different between the groups when evaluated before and after shift-work (P >0.05). However in both ICU and non-ICU physicians, sleep latency was observed to be decreased within the three consecutive-day period after shift-work with respect to basal values (P <0.001). Total sleep time, total activity score and sleep efficiency scores prior to shift-work were significantly different from shift-work and the three consecutive-days after shift-work, in both groups. Working in the ICU does not have an impact on objective sleep characteristics of physicians in this study. Large cohort studies are required to determine long-term health concerns of shift-working physicians.
International Retrieval of Adults on Extracorporeal Membrane Oxygenation Support
Authors: Forrest P. , Cheong J. Y. , Vallely M. P. , Torzillo P. J. , Hendel P. N. , Wilson M. K. , Bannon P. G. , Bayfield M. S. , Herkes R. , Walker S. W.
Published: January 2019

A retrieval service was established in New South Wales to provide mobile extracorporeal membrane oxygenation support to patients with severe, acute cardiac or respiratory failure. This service has also retrieved four adult patients from Nouméa, New Caledonia to Sydney on extracorporeal membrane oxygenation support, which are the first international retrievals of this type from Australia. We discuss our experience with these patients, three of whom survived to hospital discharge. However, one patient referred from New Caledonia died before extracorporeal membrane oxygenation could be established.
The Mitochondrial Permeability Transition Pore and its Role in Anaesthesia-Triggered Cellular Protection during Ischaemia-Reperfusion Injury
Authors: Andrews D. T. , Royse C. F. , Royse A. G.
Published: January 2019

This review summarises the most recent data in support of the role of the mitochondrial permeability transition pore (mPTP) in ischaemia-reperfusion injury, how anaesthetic agents interact with this molecular channel, and the relevance this holds for current anaesthetic practice. Ischaemia results in damage to the electron transport chain of enzymes and sets into play the assembly of a non-specific mega-channel (the mPTP) that transgresses the inner mitochondrial membrane. During reperfusion, uncontrolled opening of the mPTP causes widespread depolarisation of the inner mitochondrial membrane, hydrolysis of ATP, mitochondrial rupture and eventual necrotic cell death. Similarly, transient opening of the mPTP during less substantial ischaemia leads to differential swelling of the intermembrane space compared to the mitochondrial matrix, rupture of the outer mitochondrial membrane and release of pro-apoptotic factors into the cytosol. Recent data suggests that cellular protection from volatile anaesthetic agents follows specific downstream interactions with this molecular channel that are initiated early during anaesthesia. Intravenous anaesthetic agents also prevent the opening of the mPTP during reperfusion. Although by dissimilar mechanisms, both volatiles and propofol promote cell survival by preventing uncontrolled opening of the mPTP after ischaemia. It is now considered that anaesthetic-induced closure of the mPTP is the underlying effector mechanism that is responsible for the cytoprotection previously demonstrated in clinical studies investigating anaesthetic-mediated cardiac and neuroprotection. Manipulation of mPTP function offers a novel means of preventing ischaemic cell injury. Anaesthetic agents occupy a unique niche in the pharmacological armamentarium available for use in preventing cell death following ischaemia-reperfusion injury.
Emergency Surgery in the Elderly: A Retrospective Observational Study
Authors: Alcock M. , Chilvers C. R.
Published: January 2019

We conducted a retrospective observational study in a regional hospital on patients aged 80 years or over undergoing emergency procedures. We included 202 emergency procedures performed on 178 patients over 185 separate admissions. The aim was to obtain a ‘snapshot’ of the risks of emergency surgery in the elderly and to analyse functional status both as a risk factor and as an outcome in this patient group. The most common complications were infective (21% of patients), cardiovascular (18%) and neurological (18%). Overall mortality was 9%. Increasing age, higher American Society of Anesthesiologists physical status score and poorer pre-admission functional status appeared to be associated with increased complications and mortality. Although two-thirds of both functionally independent and partially dependent patients were discharged at their original level of function, 28% of partially dependent patients required discharge to a high-level care nursing home, whereas only 5% of the initially independent patients had this poor outcome. Improvement in our ability to stratify risk in this enlarging patient group should help improve our clinical decision-making, which may have benefits both for patients and resource allocation.
Plasma Free Cortisol and B-Type Natriuretic Peptide in Septic Shock
Authors: Sturgess D. J. , Venkatesh B.
Published: January 2019

Previous studies of patients with septic shock have independently demonstrated alterations in plasma concentrations of B-type natriuretic peptide and plasma free cortisol. Previous data suggest that a reciprocal relationship might exist. However, the relationship between these hormones in patients with septic shock is unclear. We sought to compare paired measurement of both B-type natriuretic peptide and plasma free cortisol in a study of septic shock patients.

Twenty-one consecutive adult patients from a tertiary level, multidisciplinary intensive care unit underwent blood collection within 72 hours of developing septic shock. Mean±SD Acute Physiology and Chronic Health Evaluation III score was 80.1±23.8. Hospital mortality was 29%. Log plasma free cortisol demonstrated positive correlation with log B-type natriuretic peptide (r=0.55, P=0.019). Log plasma free cortisol also correlated with Acute Physiology and Chronic Health Evaluation III score (r=0.67, P P=0.01). Acute Physiology and Chronic Health Evaluation III (P=0.001) and noradrenaline dose (P=0.02) were independent predictors of plasma free cortisol. A model incorporating both variables explained 68% of variation in plasma free cortisol (R-square=0.682).

This study of patients with septic shock demonstrates a previously unappreciated positive correlation between plasma free cortisol and b-type natriuretic peptide concentration. Acute Physiology and Chronic Health Evaluation III score and noradrenaline dose were independent predictors of plasma free cortisol.
End-of-Life Practices in a Tertiary Intensive Care Unit in Saudi Arabia
Authors: Aldawood A. S. , Alsultan M. , Arabi Y. M. , Baharoon S. A. , Al-Qahtani S. , Haddad S. H. , Al-Dorzi H. M. , Al-Jahdali H. , Alatassi A. , Rishu A. H.
Published: January 2019

Our aim was to evaluate end-of-life practices in a tertiary intensive care unit in Saudi Arabia. A prospective observational study was conducted in the medical-surgical intensive care unit of a teaching hospital in Riyadh, Saudi Arabia. Over the course of the one-year study period, 176 patients died and 77% of these deaths were preceded by end-of-life decisions. Of these, 66% made do-not-resuscitate decisions, 30% decided to withhold life support and 4% withdrew life support. These decisions were made after a median time of four days (Q1 to Q3: 1 to 9) and at least one day before death (Q1 to Q3: 1 to 4). The patients’ families or surrogates were informed for 88% of the decisions and all decisions were documented in the patients’ medical records. Despite religious and cultural values, more than three-quarters of the patients whose deaths were preceded by end-of-life decisions gave do-not-resuscitate decisions before death. These decisions should be made early in the patients’ stay in the intensive care unit.
Ventilator versus Manual Hyperinflation in Clearing Sputum in Ventilated Intensive Care Unit Patients
Authors: Dennis D. , Jacob W. , Budgeon C.
Published: January 2019

The aim of hyperinflation in the ventilated intensive care unit patient is to increase oxygenation, reverse lung collapse and clear sputum. The efficacy and consistency of manual hyperventilation is well supported in the literature, but there is limited published evidence supporting hyperventilation utilising a ventilator. Despite this, a recent survey established that almost 40% of Australian tertiary intensive care units utilise ventilator hyperinflation. The aim of this non-inferiority cross-over study was to determine whether ventilator hyperinflation was as effective as manual hyperinflation in clearing sputum from patients receiving mechanical ventilation using a prescriptive ventilator hyperinflation protocol. A total of 46 patients received two randomly ordered physiotherapy treatments on the same day by the same physiotherapist. The efficacy of the hyperinflation modes was measured by sputum wet weight. Secondary measures included compliance, tidal volume, airway pressure and PaO2/FiO2 ratio. There was no difference in wet weight of sputum cleared using ventilator hyperinflation or manual hyperinflation (mean 3.2 g, P=0.989). Further, no difference in compliance (P=0.823), tidal volume (P=0.219), heart rate (P=0.579), respiratory rate (P=0.929) or mean arterial pressure (P=0.593) was detected. A statistically significant difference was seen in mean airway pressure (P=0.002) between techniques. The effect of techniques on the PaO2/FiO2 response ratio was dependent on time (interaction P=0.024). Physiotherapy using ventilator hyperinflation cleared a comparable amount of sputum and was as safe as manual hyperinflation. This research describes a ventilator hyperinflation protocol that will serve as a platform for continued discussion, research and development of its application in ventilated patients.
A New Technique for Post-Pyloric Feeding Tube Placement by Palpation in Lean Critically Ill Patients
Authors: Sekino M. , Yoshitomi O. , Nakamura T. , Makita T. , Sumikawa K.
Published: January 2019

Various techniques have been described for blind bedside placement of a post-pyloric feeding tube. However, there is no universal method and the technique depends on the local institutional resources and expertise. The purpose of this study was to evaluate a simple new technique for the bedside placement of a post-pyloric feeding tube in an intensive care unit using palpation to confirm tube position.

We studied 47 consecutive ventilated patients (mean body mass index 22.4±4.2 kg/m2) requiring enteral tube feeding for nutritional support. We monitored the maximum intensity point of injected air ‘bubbling’ by palpation and estimated tube position. We monitored the movement of the maximum intensity point from the left upper quadrant to the right upper quadrant. If the maximum intensity point on the right upper quadrant diminished or weakened, we considered the tube had proceeded beyond the pylorus.

By palpation, we could feel the bubbling of the injected air in all patients, but four patients were excluded because of failure to complete the protocol. The overall success rate including the four excluded cases was 85.1% (40/47) on the first attempt and 91.5% (43/47) when we included the second attempt. The median time for 40 successful tube placements on the first attempt was 10 (7 to 23) minutes.

Our new palpation technique can successfully detect the position of a feeding tube in the stomach and help guide the tube to the correct location in the post-pyloric portion of the stomach in lean critically ill patients.
Determinants of Family Satisfaction in the Intensive Care Unit
Authors: Sundararajan K. , Sullivan T. R. , Chapman M.
Published: January 2019

The aim of this study was to explore the degree and determinants of satisfaction of family members of patients being cared for in an Australasian intensive care unit. This was a prospective observational study that took place within a mixed medical/surgical, level three intensive care unit. One hundred and eight family members of patients staying in the intensive care for more than 48 hours were identified. Eight were excluded because next of kin contact details were unavailable. A questionnaire was posted to next of kin four weeks after intensive care unit discharge. Subjects who had not responded after four weeks were contacted by telephone and, if consent was given, a phone questionnaire was performed. Evidence of family meetings with the social worker or medical staff was sought in the patients’ case notes retrospectively. Family satisfaction was measured using a 10-item questionnaire incorporating visual analogue scales. Seven subjects refused to participate. Fifty-nine responded by post and a further 25 agreed to a phone interview. Nine subjects were unable to be contacted. Eighty-four family members were included, 73 of patients who survived. Overall family satisfaction was a high 8.0 (interquartile range 6.5 to 9.5). Highest scores recorded were for communications with nursing staff (9.0), while lowest scores were for frequency of doctors’ communication (7.0). Families who had meetings with the social worker or medical staff were less likely to report dissatisfaction (relative risk 0.14; confidence interval 0.03 to 0.59; P=0.08; relative risk 0.23; confidence interval 0.07 to 0.81; P=0.02). Our study found that the majority of families are happy with their care in the intensive care unit. Social work and medical meetings with the family reduce dissatisfaction.
Histamine-Releasing and Allergenic Properties of Opioid Analgesic Drugs: Resolving the Two
Authors: Baldo B. A. , Pham N. H.
Published: January 2019

Opioid analgesics are amongst the most commonly administered drugs in hospitals. Whether natural or synthetic, they show some common structural features, morphine-like pharmacological action and binding specificity for complementary opioid receptors. Tramadol differs from the other opioid analgesics in possessing monoaminergic activity in addition to its affinity for the μ opioid receptor.

Many opioids are potent histamine releasers producing a variety of haemodynamic changes and anaphylactoid reactions, but the relationship of the appearance of these effects to the histamine plasma concentration is complex and there is no direct and invariable relationship between the two. Studies of the histamine-releasing effects, chiefly centred on morphine, reveal variable findings and conclusions often due to a range of factors including differences in technical measurements, dose, mode of administration, site of injection, the anatomical distribution of histamine receptors and heterogeneity of patient responses. Morphine itself has multiple direct effects on the vasculature and other haemodynamically-active mediators released along with histamine contribute to the variable responses to opioid drug administration.

Despite their heavy use and occasional apparent anaphylactic-like side-effects, immunoglobulin E antibody-mediated immediate hypersensitivity reactions to the drugs are not often encountered. Uncertainties associated with skin testing with these known histamine-releasers, and the general unavailability of opioid drug-specific immunoglobulin E antibody tests contribute to the frequent failure to adequately investigate and establish underlying mechanisms of reactions by distinguishing anaphylactoid from true anaphylactic reactions. Clinical implications for diagnosis of reactions and some speculations on the rarity of true Type 1 allergies to these drugs are presented.
Respiratory Dysfunction in Ventilated Patients: Can Inspiratory Muscle Training Help?
Authors: Bissett B. , Leditschke I. A. , Paratz J. D. , Boots R. J.
Published: January 2019

Respiratory muscle dysfunction is associated with prolonged and difficult weaning from mechanical ventilation. This dysfunction in ventilator-dependent patients is multifactorial: there is evidence that inspiratory muscle weakness is partially explained by disuse atrophy secondary to ventilation, and positive end-expiratory pressure can further reduce muscle strength by negatively shifting the length-tension curve of the diaphragm. Polyneuropathy is also likely to contribute to apparent muscle weakness in critically ill patients, and nutritional and pharmaceutical effects may further compound muscle weakness. Moreover, psychological influences, including anxiety, may contribute to difficulty in weaning. There is recent evidence that inspiratory muscle training is safe and feasible in selected ventilator-dependent patients, and that this training can reduce the weaning period and improve overall weaning success rates. Extrapolating from evidence in sports medicine, as well as the known effects of inspiratory muscle training in chronic lung disease, a theoretical model is proposed to describe how inspiratory muscle training enhances weaning and recovery from mechanical ventilation. Possible mechanisms include increased protein synthesis (both Type 1 and Type 2 muscle fibres), enhanced limb perfusion via dampening of a sympathetically-mediated metaboreflex, reduced lactate levels and modulation of the perception of exertion, resulting in less dyspnoea and enhanced exercise capacity.
Systematic Review of Oxytocin Dosing at Caesarean Section
Authors: Stephens L. C. , Bruessel T.
Published: January 2019

We undertook a systematic review to determine the optimal dose of oxytocin after elective caesarean section or caesarean section in labouring women. We identified seven trials. These trials raise questions about the use of high dose (10 international units; IU) or moderate dose (5 IU) oxytocin in both settings and provide evidence that lower doses are equally effective but associated with significantly fewer side-effects. For elective caesarean section, a slow 0.3 to 1 IU bolus of oxytocin over one minute, followed by an infusion of 5 to 10 IU.h−1 for four hours represents an evidence-based approach to dosing for women at low risk of postpartum haemorrhage. For the labouring parturient a slow 3 IU bolus of oxytocin, followed by an infusion of 5 to 10 IU.h−1 for four hours is supported by limited evidence. These doses represent a starting point in the control of postpartum haemorrhage after caesarean section and do not reduce the need for mandatory active observation of the clinical situation, to detect situations that require additional doses of oxytocin or other uterotonic drugs. These doses of oxytocin minimise the risk of adverse haemodynamic changes as well as the unpleasant side-effect of nausea.