Protocol summary and statistical analysis plan for the low oxygen intervention for cardiac arrest injury limitation (LOGICAL) trial.

Background: The effect of conservative vs. liberal oxygen therapy on outcomes of intensive care unit (ICU) patients with hypoxic ischaemic encephalopathy (HIE) is uncertain and will be evaluated in the Low Oxygen Intervention for Cardiac Arrest injury Limitation (LOGICAL) trial. Objective: The objective of this study was to summarise the protocol and statistical analysis plans for the LOGICAL trial. Design setting and participants: LOGICAL is a randomised clinical trial in adults in the ICU who are comatose with suspected HIE (i.e., those who have not obeyed commands following return of spontaneous circulation after a cardiac arrest where there is clinical concern about possible brain damage). The LOGICAL trial will include 1400 participants and is being conducted as a substudy of the Mega Randomised registry trial comparing conservative vs. liberal oxygenation targets in adults receiving unplanned invasive mechanical ventilation in the ICU (Mega-ROX). Main outcome measures: The primary outcome is survival with favourable neurological function at 180 days after randomisation as measured with the Extended Glasgow Outcome Scale (GOS-E). A favourable neurological outcome will be defined as a GOS-E score of lower moderate disability or better (i.e. a GOS-E score of 5-8). Secondary outcomes include survival time, day 180 mortality, duration of invasive mechanical ventilation, ICU length of stay, hospital length of stay, the proportion of patients discharged home, quality of life assessed at day 180 using the EQ-5D-5L, and cognitive function assessed at day 180 using the Montreal Cognitive Assessment (MoCA-blind). Conclusions: The LOGICAL trial will provide reliable data on the impact of conservative vs. liberal oxygen therapy in ICU patients with suspected HIE following resuscitation from a cardiac arrest. Prepublication of the LOGICAL protocol and statistical analysis plan prior to trial conclusion will reduce the potential for outcome-reporting or analysis bias. Trial registration: Australian and New Zealand Clinical Trials Registry (ACTRN12621000518864).

Clinical Informatics needs to be a competency for Intensive care training.

Clinical informatics is a cornerstone in the delivery of safe and quality critical care in Australia and New Zealand. Recent advances in the field of clinical informatics, including new technologies that digitise healthcare data, improved methods of capturing and storing these data, as well as innovative analytic methods using machine learning and artificial intelligence, present exciting new opportunities to leverage data for improving the delivery of critical care and patient outcomes. However, ICU training in Australian and New Zealand does not adequately address capability gaps in this area, potentially leaving future intensivists without the necessary skills to provide leadership in the application of informatics within ICUs. This highlights the need to examine how competency in clinical informatics can be incorporated into ICU training, potentially through a range of activities such as curriculum redesign, the formal project, and workshops or datathons. Further work to identify relevant informatics competencies and methods to develop and assess these competencies within ICU training is needed.

Thirty years of ANZICS CORE: A clinical quality success story.

In 2023, the Australian and New Zealand Intensive Care Society (ANZICS) Registry run by the Centre for Outcomes and Resources Evaluation (CORE) turns 30 years old. It began with the Adult Patient Database, the Australian and New Zealand Paediatric Intensive Care Registry, and the Critical Care Resources Registry, and it now includes Central Line Associated Bloodstream Infections Registry, the Extra-Corporeal Membrane Oxygenation Database, and the Critical Health Resources Information System. The ANZICS Registry provides comparative case-mix reports, risk-adjusted clinical outcomes, process measures, and quality of care indicators to over 200 intensive care units describing more than 200 000 adult and paediatric admissions annually. The ANZICS CORE outlier management program has been a major contributor to the improved patient outcomes and provided significant cost savings to the healthcare sector. Over 200 peer-reviewed papers have been published using ANZICS Registry data. The ANZICS Registry was a vital source of information during the COVID-19 pandemic. Upcoming developments include reporting of long-term survival and patient-reported outcome and experience measures.

Measuring the Impact of ICU Strain on Mortality, After-Hours Discharge, Discharge Delay, Interhospital Transfer, and Readmission in Australia With the Activity Index.

OBJECTIVES: ICU resource strain leads to adverse patient outcomes. Simple, well-validated measures of ICU strain are lacking. Our objective was to assess whether the "Activity index," an indicator developed during the COVID-19 pandemic, was a valid measure of ICU strain. DESIGN: Retrospective national registry-based cohort study. SETTING: One hundred seventy-five public and private hospitals in Australia (June 2020 through March 2022). SUBJECTS: Two hundred seventy-seven thousand seven hundred thirty-seven adult ICU patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Data from the Australian and New Zealand Intensive Care Society Adult Patient Database were matched to the Critical Health Resources Information System. The mean daily Activity index of each ICU (census total of "patients with 1:1 nursing" + "invasive ventilation" + "renal replacement" + "extracorporeal membrane oxygenation" + "active COVID-19," divided by total staffed ICU beds) during the patient's stay in the ICU was calculated. Patients were categorized as being in the ICU during very quiet (Activity index < 0.1), quiet (0.1 to < 0.6), intermediate (0.6 to < 1.1), busy (1.1 to < 1.6), or very busy time-periods (≥ 1.6). The primary outcome was in-hospital mortality. Secondary outcomes included after-hours discharge from the ICU, readmission to the ICU, interhospital transfer to another ICU, and delay in discharge from the ICU. Median Activity index was 0.87 (interquartile range, 0.40-1.24). Nineteen thousand one hundred seventy-seven patients died (6.9%). In-hospital mortality ranged from 2.4% during very quiet to 10.9% during very busy time-periods. After adjusting for confounders, being in an ICU during time-periods with higher Activity indices, was associated with an increased risk of in-hospital mortality (odds ratio [OR], 1.49; 99% CI, 1.38-1.60), after-hours discharge (OR, 1.27; 99% CI, 1.21-1.34), readmission (OR, 1.18; 99% CI, 1.09-1.28), interhospital transfer (OR, 1.92; 99% CI, 1.72-2.15), and less delay in ICU discharge (OR, 0.58; 99% CI, 0.55-0.62): findings consistent with ICU strain. CONCLUSIONS: The Activity index is a simple and valid measure that identifies ICUs in which increasing strain leads to progressively worse patient outcomes.

Sodium Bicarbonate for Metabolic Acidosis in the ICU: Results of a Pilot Randomized Double-Blind Clinical Trial.

OBJECTIVES: To identify the best population, design of the intervention, and to assess between-group biochemical separation, in preparation for a future phase III trial. DESIGN: Investigator-initiated, parallel-group, pilot randomized double-blind trial. SETTING: Eight ICUs in Australia, New Zealand, and Japan, with participants recruited from April 2021 to August 2022. PATIENTS: Thirty patients greater than or equal to 18 years, within 48 hours of admission to the ICU, receiving a vasopressor, and with metabolic acidosis (pH < 7.30, base excess [BE] < -4 mEq/L, and Pa co2 < 45 mm Hg). INTERVENTIONS: Sodium bicarbonate or placebo (5% dextrose). MEASUREMENTS AND MAIN RESULT: The primary feasibility aim was to assess eligibility, recruitment rate, protocol compliance, and acid-base group separation. The primary clinical outcome was the number of hours alive and free of vasopressors on day 7. The recruitment rate and the enrollment-to-screening ratio were 1.9 patients per month and 0.13 patients, respectively. Time until BE correction (median difference, -45.86 [95% CI, -63.11 to -28.61] hr; p < 0.001) and pH correction (median difference, -10.69 [95% CI, -19.16 to -2.22] hr; p = 0.020) were shorter in the sodium bicarbonate group, and mean bicarbonate levels in the first 24 hours were higher (median difference, 6.50 [95% CI, 4.18 to 8.82] mmol/L; p < 0.001). Seven days after randomization, patients in the sodium bicarbonate and placebo group had a median of 132.2 (85.6-139.1) and 97.1 (69.3-132.4) hours alive and free of vasopressor, respectively (median difference, 35.07 [95% CI, -9.14 to 79.28]; p = 0.131). Recurrence of metabolic acidosis in the first 7 days of follow-up was lower in the sodium bicarbonate group (3 [20.0%] vs. 15 [100.0%]; p < 0.001). No adverse events were reported. CONCLUSIONS: The findings confirm the feasibility of a larger phase III sodium bicarbonate trial; eligibility criteria may require modification to facilitate recruitment.

Mortality among people admitted to Australian intensive care units for reasons other than COVID-19 during the COVID-19 pandemic: a retrospective cohort study.

OBJECTIVE: To investigate in-hospital mortality among people admitted to Australian intensive care units (ICUs) with conditions other than coronavirus disease 2019 (COVID-19) during the COVID-19 pandemic. DESIGN: National, multicentre, retrospective cohort study; analysis of data in the Australian and New Zealand Intensive Care Society Centre for Outcome and Resource Evaluation (ANZICS CORE) Adult Patient Database. SETTING, PARTICIPANTS: Adults (16 years or older) without COVID-19 admitted to Australian ICUs, 1 January 2016 - 30 June 2022. MAIN OUTCOME MEASURES: All-cause in-hospital mortality, unadjusted and relative to the January 2016 value, adjusted for illness severity (Australian and New Zealand Risk of Death [ANZROD] and hospital type), with ICU as a random effect. Points of change in mortality trends (breakpoints) were identified by segmental regression analysis. RESULTS: Data for 950 489 eligible admissions to 186 ICUs were available. In-hospital mortality declined steadily from January 2016 to March 2021 by 0.3% per month (P < 0.001; March 2021 v January 2016: adjusted odds ratio [aOR], 0.70; 95% confidence interval [CI], 0.62-0.80), but rose by 1.4% per month during March 2021 - June 2022 (P < 0.001; June 2022 v January 2016: aOR, 1.03; 95% CI, 0.90-1.17). The rise in mortality continued after the number of COVID-19-related ICU admissions had declined; mortality increased in jurisdictions with lower as well as in those with higher numbers of COVID-19-related ICU admissions. CONCLUSION: The rise in in-hospital mortality among people admitted to Australian ICUs with conditions other than COVID-19 from March 2021 reversed the improvement of the preceding five years. Changes to health service delivery during the pandemic and their consequences should be investigated further.

A Retrospective Cohort Study of Red Cell Alloimmunisation in Rural, Remote, and Aboriginal and Torres Strait Islander Peoples Admitted to Intensive Care in the Northern Territory, Australia.

Red cell (RC) alloantibodies occur on exposure to non-self RC antigens in transfusion and pregnancy (typically IgG and clinically significant) or in association with non-RC immune environmental factors (typically IgM and not clinically significant). In Australia, the risk of RC alloimmunisation in First Nations peoples is unknown. We assessed the epidemiology, specificity, and antecedents of RC alloimmunisation via a data linkage retrospective cohort study of Northern Territory (NT) intensive care unit (ICU) patients (2015-2019). Of 4183 total patients, 50.9% were First Nations. In First Nations versus non-First Nations patients, the period prevalence of alloimmunisation was 10.9% versus 2.3%, with 390 versus 72 prevalent alloantibodies detected in 232 versus 48 alloimmunised patients, of which 135 (34.6%) versus 52 (72.2%) were clinically significant specificities. Baseline and follow-up alloantibody testing were available for 1367 patients, in whom new incident clinically significant alloantibodies developed in 4.5% First Nations versus 1.1% non-First Nations patients. On Cox proportional hazards modelling, adjusted hazard ratios (HR) showed First Nations status (HR 2.67 (95% CI 1.05-6.80), p = 0.04) and cumulative RC unit transfusion exposure (HR 1.03 (95% CI 1.01-1.05), p = 0.01) were independent predictors of clinically significant alloimmunisation. First Nations Australian patients are at increased risk of alloimmunisation due to RC transfusion, underscoring the importance of very judicious use of RC transfusions and shared decision-making with patients. Further studies are recommended to explore the role of other (non-RC) immune host factors, given the relative high prevalence of non-clinically significant IgM alloantibodies within alloimmunised First Nations patients.

Prediction accuracy of commonly used pneumonia severity scores in Aboriginal patients with severe community-acquired pneumonia: a retrospective study.

BACKGROUND: Severe community-acquired pneumonia (SCAP) is highly prevalent in the Aboriginal population. Few pneumonia severity scores are validated in this population. AIMS: To assess the prediction accuracy of pneumonia severity scores in Aboriginal patients with SCAP and to identify risk factors for poor prognosis. METHODS: Retrospective cohort study examining Aboriginal patients admitted to the intensive care unit with confirmed SCAP between January 2011 and December 2014. Severity scores were calculated for SMARTCOP (systolic blood pressure, multi-lobar, albumin, respiratory rate, tachycardia, confusion, oxygenation and arterial pH), SMARTACOP (systolic blood pressure, multi-lobar, albumin, respiratory rate, tachycardia, Aboriginal status, confusion, oxygenation and arterial pH), CURB-65 (confusion, urea, respiratory rate, blood pressure and age ≥65 years), pneumonia severity index, Infectious Diseases Society of America and American Thoracic Society SCAP, and Acute Physiology and Chronic Health Evaluation (APACHE) II/III using medical records. Prediction accuracy of 30-day mortality and requirement for intensive respiratory and/or vasoactive support (IRVS) were assessed using logistic regression and the area under the receiver operating characteristic curve (AUROC). Multivariate analysis was used to test associations between poor prognosis and demographic/clinical variables. RESULTS: A total of 203 cases (49% women) was identified. Thirty-day mortality was 6.4% (n = 13), and 53% (n = 107) required IRVS. None of the tested pneumonia severity scores accurately predicted mortality. SMARTCOP and SMARTACOP predicted IRVS requirement with the highest diagnostic accuracy, but only achieved acceptable discrimination (P <0.001 and <0.001; AUROC = 0.74 and 0.75 respectively). APACHE II/III predicted both mortality (P = 0.003 and 0.001; AUROC = 0.74 and 0.73 respectively) and IRVS requirement (P <0.001 and <0.001; AUROC = 0.72 and 0.73 respectively). Multivariate analysis associated mortality with male gender, cirrhosis, immunosuppression and acidaemia, and IRVS requirement with multi-lobar pneumonia, hypotension and tachypnoea. Multivariate analysis for mortality and IRVS requirement achieved an AUROC of 0.93 and 0.87 respectively. CONCLUSION: None of the pneumonia severity scores accurately predicted mortality. We recommend SMARTACOP to predict IRVS requirement in Aboriginal patients with SCAP. Given Aboriginal patients are over-represented in Australian intensive care units, a new score is warranted for this understudied population.

Twelve-month mortality outcomes for Indigenous and non-Indigenous people admitted to intensive care units in Australia: a registry-based data linkage study.

OBJECTIVE: To compare longer term (12-month) mortality outcomes for Indigenous and non-Indigenous people admitted to intensive care units (ICUs) in Australia. DESIGN, SETTING, PARTICIPANTS: Retrospective registry-based data linkage cohort study; analysis of all admissions of adults (16 years or older) to Australian ICUs, 1 January 2017 - 31 December 2019, as recorded in the Australian and New Zealand Intensive Care Society (ANZICS) Adult Patient Database (APD), linked using the SLK-581 key to National Death Index data. MAIN OUTCOME MEASURES: Unadjusted and adjusted mortality risk, censored at twelve months from the start of index ICU admission. Secondary outcomes were unadjusted and adjusted mortality twelve months from admission to the ICU. RESULTS: The APD recorded 330 712 eligible ICU admissions during 2017-2019 (65% of all ICU admissions registered), of which 11 322 were of Indigenous people (3.4%). Median age at admission was lower for Indigenous patients (51.2 [IQR, 36.7-63.6] years) than for non-Indigenous patients (66.5 [IQR, 52.7-76.1] years). Unadjusted mortality risk was similar for Indigenous and non-Indigenous patients (hazard ratio, 1.01; 95% CI, 0.97-1.06), but was higher for Indigenous patients after adjusting for age, admission diagnosis, illness severity, hospital type, jurisdiction, remoteness and socio-economic status (adjusted hazard ratio, 1.20; 95% CI, 1.14-1.27). Twelve-month mortality was higher for Indigenous than non-Indigenous patients (adjusted odds ratio, 1.24; 95% CI, 1.16-1.33). CONCLUSIONS: Twelve-month mortality outcomes are poorer for people admitted to ICUs in Australia than for the general population. Further, after adjusting for age and other factors, survival outcomes are poorer for Indigenous than non-Indigenous people admitted to ICUs. Critical illness may therefore contribute to shorter life expectancy among Indigenous Australians.

Association Between Centralization and Outcome for Children Admitted to Intensive Care in Australia and New Zealand: A Population-Based Cohort Study.

OBJECTIVES: To describe regional differences and change over time in the degree of centralization of pediatric intensive care in Australia and New Zealand (ANZ) and to compare the characteristics and ICU mortality of children admitted to specialist PICUs and general ICUs (GICUs). DESIGN: A retrospective cohort study using registry data for two epochs of ICU admissions, 2003-2005 and 2016-2018. SETTING: Population-based study in ANZ. PATIENTS: A total of 43,256 admissions of children aged younger than 16 years admitted to an ICU in ANZ were included. Infants aged younger than 28 days without cardiac conditions were excluded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was risk-adjusted ICU mortality. Logistic regression was used to investigate the association of mortality with the exposure to ICU type, epoch, and their interaction. Compared with children admitted to GICUs, children admitted to PICUs were younger (median 25 vs 47 mo; p < 0.01) and stayed longer in ICU (median 1.6 vs 1.0 d; p < 0.01). For the study overall, 93% of admissions in Australia were to PICUs whereas in New Zealand only 63% of admissions were to PICUs. The adjusted odds of death in epoch 2 relative to epoch 1 decreased (adjusted odds ratio [AOR], 0.50; 95% CI, 0.42-0.59). There was an interaction between unit type and epoch with increased odds of death associated with care in a GICU in epoch 2 (AOR, 1.63; 95% CI, 1.05-2.53 for all admissions; 1.73, CI, 1.002-3.00 for high-risk admissions). CONCLUSIONS: Risk-adjusted mortality of children admitted to specialist PICUs decreased over a study period of 14 years; however, a similar association between time and outcome was not observed in high-risk children admitted to GICUs. The results support the continued use of a centralized model of delivering intensive care for critically ill children.

The Effect of a Liberal Approach to Glucose Control in Critically Ill Patients with Type 2 Diabetes: A Multicenter, Parallel-Group, Open-Label Randomized Clinical Trial.

Rationale: Blood glucose concentrations affect outcomes in critically ill patients, but the optimal target blood glucose range in those with type 2 diabetes is unknown. Objectives: To evaluate the effects of a "liberal" approach to targeted blood glucose range during ICU admission. Methods: This mutlicenter, parallel-group, open-label randomized clinical trial included 419 adult patients with type 2 diabetes expected to be in the ICU on at least three consecutive days. In the intervention group intravenous insulin was commenced at a blood glucose >252 mg/dl and titrated to a target range of 180-252 mg/dl. In the comparator group insulin was commenced at a blood glucose >180 mg/dl and titrated to a target range of 108-180 mg/dl. The primary outcome was incident hypoglycemia (<72 mg/dl). Secondary outcomes included glucose metrics and clinical outcomes. Measurements and Main Results: By Day 28, at least one episode of hypoglycemia occurred in 10 of 210 (5%) patients assigned the intervention and 38 of 209 (18%) patients assigned the comparator (incident rate ratio, 0.21 [95% confidence interval (CI), 0.09 to 0.49]; P < 0.001). Those assigned the intervention had greater blood glucose concentrations (daily mean, minimum, maximum), less glucose variability, and less relative hypoglycemia (P < 0.001 for all comparisons). By Day 90, 62 of 210 (29.5%) in the intervention and 52 of 209 (24.9%) in the comparator group had died (absolute difference, 4.6 percentage points [95% CI, -3.9% to 13.2%]; P = 0.29). Conclusions: A liberal approach to blood glucose targets reduced incident hypoglycemia but did not improve patient-centered outcomes. Clinical trial registered with Australian New Zealand Clinical Trials Registry (ACTRN 12616001135404).

The impact of obesity on outcomes of patients admitted to intensive care after cardiac arrest.

PURPOSE: Studies examining the association between obesity and mortality in cardiac arrest patients have been conflicting which might either be due to residual confounding, or a reliance on estimating the conditional effects rather than the marginal (causal) effects of obesity. We estimated the conditional and causal effects of obesity on mortality in cardiac arrest patients using the Australian and New Zealand Intensive Care Society (ANZICS) Adult Patient Database (APD). MATERIALS AND METHODS: This retrospective registry-based cohort study from ICUs of Australia and New Zealand included all ICU patients admitted with cardiac arrest between 2010 and 2020 with height and weight data recorded. The conditional and marginal effects of obesity on mortality was estimated using multivariate binary logistic regression and Targeted Maximum Likelihood Estimation (TMLE) respectively. The primary outcome was in-hospital mortality. RESULTS: A total 13,970 patients had complete data and were available for analysis. In multivariate binary logistic regression, there was no difference in the odds of in-hospital mortality for the obese versus non-obese groups; adjusted OR = 0.95, 95% CI = 0.87-1.03; p 0.25. Results were similar using TMLE (Marginal OR= 0.97; 95% CI = 0.91-1.02, p = 0.62). CONCLUSION: After adjustment, there was no association between obesity and outcomes in cardiac arrest patients admitted to ICU.

Clinical outcomes of Indigenous Australians and New Zealand Maori with metabolic acidosis and acidaemia.

Objective: To assess the incidence and impact of metabolic acidosis in Indigenous and non-Indigenous patients Design: Retrospective study. Setting: Adult intensive care units (ICUs) from Australia and New Zealand. Participants: Patients aged 16 years or older admitted to an Australian or New Zealand ICU in one of 195 contributing ICUs between January 2019 and December 2020 who had metabolic acidosis, defined as pH < 7.30, base excess (BE) < -4 mEq/L and PaCO2 ≤ 45 mmHg. Main outcome measures: The primary outcome was the prevalence of metabolic acidosis. Secondary outcomes included ICU length of stay, hospital length of stay, receipt of renal replacement therapy (RRT), major adverse kidney events at 30 days (MAKE30), and hospital mortality. Results: Overall, 248 563 patients underwent analysis, with 11 537 (4.6%) in the Indigenous group and 237 026 (95.4%) in the non-Indigenous group. The prevalence of metabolic acidosis was higher in Indigenous patients (9.3% v 6.1%; P < 0.001). Indigenous patients with metabolic acidosis received RRT more often (28.2% v 22.0%; P < 0.001), but hospital mortality was similar between the groups (25.8% in Indigenous v 25.8% in non-Indigenous; P = 0.971). Conclusions: Critically ill Indigenous ICU patients are more likely to have a metabolic acidosis in the first 24 hours of their ICU admission, and more often received RRT during their ICU admission compared with non-Indigenous patients. However, hospital mortality was similar between the groups.

Characteristics and outcomes of Aboriginal and Torres Strait Islander patients with dialysis-dependent kidney disease in Australian intensive care units.

BACKGROUND: In Australia, 531 people per million population have dialysis-dependent chronic kidney disease (CKD5D). The incidence is four times higher for Aboriginal and Torres Strait Islander (indigenous) people compared with non-Indigenous Australians. CKD5D increases the risk of hospitalisation, admission to the intensive care unit (ICU) and mortality compared with patients without CKD5D. There is limited literature describing short-term outcomes of patients with CKD5D who are admitted to the ICU, comparing indigenous and non-indigenous patients. AIMS: This registry-based retrospective cohort analysis compared demographic and clinical data between indigenous and non-indigenous patients with CKD5D and tested whether indigenous status predicted short-term outcomes independently of other contributing factors. Adjusted hospital mortality was the primary outcome measure. METHODS: Data were from the Australian and New Zealand Intensive Care Society's Centre for Outcome and Resource Evaluation Adult Patient Database. Australian ICU admissions between 2010 and 2017 were included. Data from 173 ICU (2136 beds) include 1 051 697 ICU admissions, of which 23 793 had a pre-existing diagnosis of CKD5D. RESULTS: Indigenous patients comprised 11.9% of CKD5D patients in ICU. CKD5D was prevalent among 4.9% of indigenous and 2.9% of non-indigenous ICU admissions. Indigenous patients were 13.5 years younger, had fewer comorbidities and lower crude mortality despite equivalent calculated mortality risk. After adjusting for age, remoteness and severity of illness, indigenous status did not predict mortality. CONCLUSIONS: Socioeconomic disadvantage contributes to earlier development of CKD5D and the overrepresentation in ICU of indigenous people. Mortality is equivalent once correcting for confounders, but addressing inequality requires strengthening preventative care.

Epidemiology and microbiology of severe community-acquired pneumonia in Central Australia: a retrospective study.

BACKGROUND: Severe community-acquired pneumonia (SCAP) has high mortality and morbidity. AIMS: To describe the epidemiology and microbiology of SCAP in Central Australia. METHODS: A retrospective epidemiological study describing the characteristics, incidence rates (IR) and microbiological aetiology of SCAP in Central Australia. Adult patients admitted to Alice Springs Hospital Intensive Care Unit (ICU) between 2011 and 2014 that fitted the Infectious Diseases Society of America and American Thoracic Society definition of SCAP were included. Medical records were reviewed and compared between indigenous and non-indigenous patients. Primary outcomes were incidence rate and microbiological aetiology of SCAP. Secondary outcomes were 30-day mortality, and ICU and hospital length of stay (LoS). RESULTS: A total of 185 patents were included (156 indigenous; 29 non-indigenous). The overall SCAP IR per 1000 person-years was 3.24 (3.75 indigenous; 1.87 non-indigenous) with an IR difference of 2.71 after adjustment (P < 0.001). Those aged ≥50 years had an IR 74.8% higher than those younger. Male IR was 50% higher than females. There was a significant difference between indigenous and non-indigenous groups for age (48 vs 64 years), but not for 30-day mortality (7.7% vs 10.3%), ICU LoS (4.8 vs 4.6 days) and hospital LoS (10.9 vs 15.1 days) respectively. Likely causative pathogen(s) were identified in 117 patients; Streptococcus pneumoniae was the most common pathogen (28.2%), followed by Haemophilus influenzae (19.7%), Influenza A/B (16.2%) and Staphylococcus aureus (14.5%). CONCLUSION: A high incidence of SCAP was observed in Central Australia, disproportionately affecting the indigenous population. Prevention strategies are imperative, as well as early identification of SCAP and appropriate empiric antibiotic regimens.

Does the use of BariBoard™ improve adequacy of chest compressions in morbid obesity? A pilot study using a simulation model.

BACKGROUND: Obesity is a growing health problem worldwide. Morbid obesity has been associated with significant barriers to effective thoracic cage compression during cardiopulmonary resuscitation. OBJECTIVE: The BariBoard™ purports to improve adequacy of chest compressions in morbidly obese patients. This study uses a simulation model to evaluate this. METHODS: This was a prospective blinded randomised-controlled crossover pilot trial using a simulation model of obesity. Participants, recruited from hospital departments and prehospital services, performed 2 minutes of continuous compressions on mannequins modified to emulate a morbidly obese patient. Participants were randomised by coin toss to a sequence of either control/intervention or intervention/control, with the BariBoard™ in the intervention arm. Accelerometers measured chest wall movement during compressions. The primary endpoint was a composite measure of compression adequacy (rate, depth, and recoil). Secondary endpoints comprised the individual components of the composite outcome, as both dichotomous outcomes (adequate vs. inadequate) and continuous variables. All endpoints were adjusted for potential confounders. RESULTS: Of 205 participants recruited, 201 were analysed. There was a significant difference in the primary outcome between the control and intervention arms (13.4% vs. 4.5%, respectively, p = 0.001) and between the control and intervention arms for the secondary endpoints of adequate compression depth (31.3% vs. 15.9%, p < 0.001) and recoil (63.7% vs. 41.3%, p < 0.001). After adjustment for confounders and interactions, there was no difference in overall efficacy (odds ratio: 0.62, 95% confidence interval: 0.20-1.90, p = 0.40). CONCLUSION: This pilot study describes the successful assessment of a device using a simulation model of obesity. Within these constraints and after adjustment for confounders, use of the BariBoard ™ did not improve efficacy of chest compressions.

Conservative management of occult pneumothorax in mechanically ventilated patients: A systematic review and meta-analysis.

BACKGROUND: The aim of this systematic review was to investigate the safety and effectiveness of conservative management versus prophylactic intercostal catheter (ICC) insertion for the management of occult pneumothoraces in mechanically ventilated patients. METHODS: PubMed, Embase, CINAHL, Web of Science, Cochrane Central, and other trial registries were searched. Eligible studies were critically appraised using standardized instruments. Meta-analysis was performed with mixed-methods logistic regression where appropriate and sensitivity analyses were performed with alternative statistical methods (Stata™ 15 or RevMan 5.3) or summarized in narrative. Randomized controlled trials (RCTs) and cohort studies were analyzed separately. RESULTS: Twelve studies with a total of 354 participants were included; three RCTs (178 participants) and nine cohort studies (176 participants). The majority of the included studies, particularly the cohort studies, were well conducted. Two of the RCTs were rated as low quality. Statistically significant differences were observed in the RCT analysis: ICC insertion (any reason) (odds ratio, 2.86; 95% confidence interval, 1.26-6.43, 2 RCTs) in favor of prophylactic ICC; ICC complications (odds ratio, 0.12; 95% confidence interval, 0.02-0.62, 2 RCTs) in favor of conservative management. Nonstatistically significant differences were observed for progression of pneumothorax, ICC insertion (progression to simple pneumothorax), and ICC insertion (nonpneumothorax reasons). Results of analyses showed high imprecision (wide confidence limits). Conservative management showed a low rate of tension pneumothorax (2.8%). Complications were higher in the ICC group (19.5% vs. 5.8%). CONCLUSION: Available evidence suggests that conservative management is safe for the management of occult pneumothoraces in mechanically ventilated patients, especially when undergoing short-term (<4 days) ventilation. We recommend that patients undergoing mechanical ventilation for a procedure alone and patients suspected to be ventilated less than 4 days can be conservatively managed. LEVEL OF EVIDENCE: Systematic review and meta-analysis, level III.

Critical care resource use associated with tourism in Central Australia.

OBJECTIVE: Tourism to regional and remote Australia is increasing. Its impact on regional critical care services is incompletely understood. We describe tourist admissions and their impact on critical care resources relative to the local population. DESIGN: Single-centre retrospective study using prospectively collected data from January 2009 to December 2018. SETTING: Australian regional intensive care unit. PARTICIPANTS: All critical care admissions for patients aged over 18 years for whom postcode data were available were included. OUTCOME MEASURES: Primary outcome was hospital mortality. Secondary outcomes examined resource use (intensive care unit and hospital length of stay, mechanical ventilation, interhospital transfer) and admission diagnosis. RESULTS: Tourists comprise 6.1% of critical care admissions, occupying 5.7% of intensive care unit bed days. They were less likely to be Indigenous (6.3% vs 72.7%), but older (61.5 vs 49.2 years) and male (65.4% vs 52.6%). They were more frequently admitted following acute myocardial infarction (14.2% vs 8.9%) or trauma (20.0% vs 5.0%). There was no difference in hospital mortality (2.9% vs 4.0%) or intensive care unit mortality (2.4% vs 1.8%); however, tourists were more than twice as likely to require interhospital transfer (31.7% vs 14.0%). These findings persisted after adjustment for illness severity. CONCLUSION: Tourists are an appreciable caseload of this regional intensive care unit and are more likely to require interhospital transfer. There was no difference in mortality. Further research is required across regional and rural Australia to better understand the epidemiology and impact of tourism on critical care resources, and the economic implications of becoming unwell in a regional area.