Race-Conscious Research Using Extracorporeal Life Support Organization Registry Data: A Narrative Review

Race-conscious research identifies health disparities with 1) rigorous and responsible data collection, 2) intentionality and considered analyses, and 3) interpretation of results that advance health equity. Individual registries must overcome specific challenges to promote race-conscious research, and this paper describes ways to achieve this with a focus on the international Extracorporeal Life Support Organization (ELSO) registry. This article reviews ELSO registry publications that studied race with outcomes to consider whether research outputs align with race-conscious concepts and describe the direction of associations reported. Studies were identified via secondary analysis of a comprehensive scoping review on ECMO disparities. Of 32 multicenter publications, two (6%) studied race as the primary objective. Statistical analyses, confounder adjustment, and inclusive, antibiased language were inconsistently used. Only two (6%) papers explicitly discussed mechanistic drivers of inequity such as structural racism, and five (16%) discussed race variable limitations or acknowledged unmeasured confounders. Extracorporeal Life Support Organization registry publications demonstrated more adverse ECMO outcomes for underrepresented/minoritized populations than non-ELSO studies. With the objective to promote race-conscious ELSO registry research outputs, we provide a comprehensive understanding of race variable limitations, suggest reasoned retrospective analytic approaches, offer ways to interpret results that advance health equity, and recommend practice modifications for data collection.

Resuscitation With Vitamin C, Hydrocortisone, and Thiamin in Children With Septic Shock: A Multicenter Randomized Pilot Study

OBJECTIVES

Adjunctive therapy with vitamin C, hydrocortisone, and thiamin has been evaluated in adults, but randomized controlled trial (RCT) data in children are lacking. We aimed to test the feasibility of vitamin C, hydrocortisone, and thiamin in PICU patients with septic shock; and to explore whether the intervention is associated with increased survival free of organ dysfunction.

DESIGN

Open-label parallel, pilot RCT multicenter study. The primary endpoint was feasibility. Clinical endpoints included survival free of organ dysfunction censored at 28 days and nine secondary outcomes, shock reversal, and two proxy measures of intervention efficacy.

SETTING

Six PICUs in Australia and New Zealand.

PATIENTS

Children of age between 28 days and 18 years requiring vasoactive drugs for septic shock between August 2019 and March 2021.

INTERVENTIONS

Patients were assigned 1:1 to receive 1 mg/kg hydrocortisone every 6 hours (q6h), 30 mg/kg ascorbic acid q6h, and 4 mg/kg thiamin every 12 hours (n = 27), or standard septic shock management (n = 33).

MEASUREMENTS AND MAIN RESULTS

Sixty of 77 (78%) eligible patients consented with 91% of approached parents providing consent. The median time from randomization to intervention was 44 (interquartile range [IQR] 29-120) min. Seventy of seventy-seven (28%) patients had received IV steroids before randomization. Median survival alive and free of organ dysfunction was 20.0 (0.0-26.0) days in the intervention and 21.0 (0.0-25.0) days in the standard care group. Median PICU length of stay was 5.3 (2.5-11.3) days in the intervention group versus 6.9 (3.0-11.5) days in the control group. Shock reversal occurred at a median of 35.2 (14.6-101.2) hours in the intervention group versus 47.3 (22.4-106.8) hours in the standard care group (median difference -12 hr; 95% CI, -56.8 to 32.7 hr).

CONCLUSIONS

In children requiring vasopressors for septic shock, a protocol comparing adjunctive treatment with high-dose vitamin C, hydrocortisone, and thiamin versus standard care was feasible. These findings assist in making modifications to the trial protocol to enable a better-designed larger RCT.

Adaptive Clinical Trials in Pediatric Critical Care: A Systematic Review

OBJECTIVES

This systematic review investigates the use of adaptive designs in randomized controlled trials (RCTs) in pediatric critical care.

DATA SOURCES

PICU RCTs, published between 1986 and 2020, stored in the www.PICUtrials.net database and MEDLINE, EMBASE, CENTRAL, and LILACS databases were searched (March 9, 2022) to identify RCTs published in 2021. PICU RCTs using adaptive designs were identified through an automated full-text screening algorithm.

STUDY SELECTION

All RCTs involving children (< 18 yr old) cared for in a PICU were included. There were no restrictions to disease cohort, intervention, or outcome. Interim monitoring by a Data and Safety Monitoring Board that was not prespecified to change the trial design or implementation of the study was not considered adaptive.

DATA EXTRACTION

We extracted the type of adaptive design, the justification for the design, and the stopping rule used. Characteristics of the trial were also extracted, and the results summarized through narrative synthesis. Risk of bias was assessed using the Cochrane Risk of Bias Tool 2.

DATA SYNTHESIS

Sixteen of 528 PICU RCTs (3%) used adaptive designs with two types of adaptations used; group sequential design and sample size reestimation. Of the 11 trials that used a group sequential adaptive design, seven stopped early due to futility and one stopped early due to efficacy. Of the seven trials that performed a sample size reestimation, the estimated sample size decreased in three trials and increased in one trial.

CONCLUSIONS

Little evidence of the use of adaptive designs was found, with only 3% of PICU RCTs incorporating an adaptive design and only two types of adaptations used. Identifying the barriers to adoption of more complex adaptive trial designs is needed.

Longitudinal cohort study investigating neurodevelopmental and socioemotional outcomes in school-entry aged children after open heart surgery in Australia and New Zealand: the NITRIC follow-up study protocol

INTRODUCTION

Despite growing awareness of neurodevelopmental impairments in children with congenital heart disease (CHD), there is a lack of large, longitudinal, population-based cohorts. Little is known about the contemporary neurodevelopmental profile and the emergence of specific impairments in children with CHD entering school. The performance of standardised screening tools to predict neurodevelopmental outcomes at school age in this high-risk population remains poorly understood. The NITric oxide during cardiopulmonary bypass to improve Recovery in Infants with Congenital heart defects (NITRIC) trial randomised 1371 children <2 years of age, investigating the effect of gaseous nitric oxide applied into the cardiopulmonary bypass oxygenator during heart surgery. The NITRIC follow-up study will follow this cohort annually until 5 years of age to assess outcomes related to cognition and socioemotional behaviour at school entry, identify risk factors for adverse outcomes and evaluate the performance of screening tools.

METHODS AND ANALYSIS

Approximately 1150 children from the NITRIC trial across five sites in Australia and New Zealand will be eligible. Follow-up assessments will occur in two stages: (1) annual online screening of global neurodevelopment, socioemotional and executive functioning, health-related quality of life and parenting stress at ages 2-5 years; and (2) face-to-face assessment at age 5 years assessing intellectual ability, attention, memory and processing speed; fine motor skills; language and communication; and socioemotional outcomes. Cognitive and socioemotional outcomes and trajectories of neurodevelopment will be described and demographic, clinical, genetic and environmental predictors of these outcomes will be explored.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Children's Health Queensland (HREC/20/QCHQ/70626) and New Zealand Health and Disability (21/NTA/83) Research Ethics Committees. The findings will inform the development of clinical decision tools and improve preventative and intervention strategies in children with CHD. Dissemination of the outcomes of the study is expected via publications in peer-reviewed journals, presentation at conferences, via social media, podcast presentations and medical education resources, and through CHD family partners.

TRIAL REGISTRATION NUMBER

The trial was prospectively registered with the Australian New Zealand Clinical Trials Registry as 'Gene Expression to Predict Long-Term Neurodevelopmental Outcome in Infants from the NITric oxide during cardiopulmonary bypass to improve Recovery in Infants with Congenital heart defects (NITRIC) Study - A Multicentre Prospective Trial'.

TRIAL REGISTRATION

ACTRN12621000904875.

Quality care close to home: Objectives and early outcomes of a second paediatric heart transplant service in Australia

AIM

We describe the experience of a new paediatric heart transplant (HT) centre in Australia. New South Wales offers quaternary paediatric cardiac services including comprehensive care pre- and post-HT; however, perioperative HT care has previously occurred at the national paediatric centre or in adult centres. Internationally, perioperative HT care is highly protocol-driven and a majority of HT occurs in low volume centres. Establishing a low volume paediatric HT centre in New South Wales offers potential for quality HT care close to home.

METHODS

Retrospective review of programme data for the first 12 months was undertaken. Patient selection was audited against the programme's intended initiation criteria. Longitudinal patient data on outcomes and complications were obtained from patient medical records.

RESULTS

The programme's initial phase offered HT to children with non-congenital heart disease and no requirement for durable mechanical circulatory support. Eight patients met criteria for HT referral. Three underwent interstate transfer to the national paediatric centre. Five children (13-15 years, weight 36-85 kg) underwent HT in the new programme. Individual predicted 90-day mortality was 1.3-11.6%, with increased risk for recipients transplanted from veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and with restrictive/hypertrophic cardiomyopathies. Survival at 90 days and for duration of follow-up is 100%. Observed programme benefits include mitigation of family dislocation and improved continuity of care within a family-centred programme.

CONCLUSION

Audit of the first 12 months' activity of a second paediatric HT centre in Australia demonstrates adherence to proposed patient selection criteria and excellent 90-day patient outcomes. The programme demonstrates feasibility of care close to home, providing continuity for all patients including those requiring increased rehabilitation and psychosocial support post-transplantation.

COVID-19 related ICU admissions in paediatric and young adult patients in Australia: a national case series 2020-2022

Background

COVID-19 pandemic research efforts have focused on disease phenotypes in adults. A distinct spectrum of illness has been documented in paediatric populations. We aimed to review paediatric intensive care unit (ICU) admissions in Australia, across differing variant predominant phases of the pandemic.

Methods

Data reported to the Short PeRiod IncideNce sTudy of Severe Acute Respiratory Infection (SPRINT-SARI) Australia, across 49 ICUs from February 2020 to June 2022 were extracted. We defined 'child' as patients aged <12 years, 'adolescent' as patients aged 12-17 years, and 'young adult' as patients aged 18-25 years.

Findings

We identified 226 paediatric ICU admissions with COVID-19, representing 3.9% of ICU admissions across the study period. Comorbidity was present in 34.6% of children, 51.4% of adolescents, and 48.7% of young adults. The need for respiratory support was highest in young adults. While 28.3% of patients <18 years required invasive ventilation, in-hospital mortality in paediatric patients was 3.6%. During the Omicron period, there was an increase in the annualised incidence of age-specific COVID-19 ICU admissions per 100,000 population, albeit a decrease in the incidence per 1000 SARS-CoV-2 notifications.

Interpretation

This study demonstrated an appreciable burden of COVID-19 in paediatric patients. Adolescent patients presented phenotypically similar to young adults, however, illness severity was lower in younger cohorts. The Omicron phase of the pandemic demonstrated an increased age-specific population incidence of COVID-19 ICU admissions, albeit a reduced incidence when based on SARS-CoV-2 notifications.

Funding

SPRINT-SARI Australia is supported by the Department of Health, Commonwealth of Australia [Standing Deed SON60002733].

Severe Influenza-Associated Neurological Disease in Australian Children: Seasonal Population-Based Surveillance 2008-2018

BACKGROUND

Influenza-associated neurological disease (IAND) is uncommon but can result in death or neurological morbidity in children. We aimed to describe the incidence, risk factors, and outcome of children with IAND from seasonal influenza in Australia.

METHODS

We analyzed national, population-based, surveillance data for children aged ≤ 14 years with severe influenza and neurological involvement, over 11 Australian influenza seasons, 2008-2018, by the Australian Paediatric Surveillance Unit.

RESULTS

There were 633 laboratory-confirmed cases of severe influenza reported. Of these, 165 (26%) had IAND. The average annual incidence for IAND was 3.39 per million children aged ≤ 14 years. Compared to cases without neurological complications, those with IAND were more likely to have a pre-existing neurological disease (odds ratio [OR] 3.03, P < .001), but most children with IAND did not (n = 135, 82%). Children with IAND were more likely to receive antivirals (OR 1.80, P = .002), require intensive care (OR 1.79, P = .001), require ventilation (OR 1.99; P = .001), and die (OR 2.83, P = .004).

CONCLUSIONS

IAND is a preventable cause of mortality, predominantly in otherwise well children. Incidence estimates validate previous sentinel site estimates from Australia. IAND accounted for a quarter of all severe influenza, is associated with intensive care unit admission, and accounted for half of all influenza deaths.

Effect of Nitric Oxide via Cardiopulmonary Bypass on Ventilator-Free Days in Young Children Undergoing Congenital Heart Disease Surgery: The NITRIC Randomized Clinical Trial

IMPORTANCE

In children undergoing heart surgery, nitric oxide administered into the gas flow of the cardiopulmonary bypass oxygenator may reduce postoperative low cardiac output syndrome, leading to improved recovery and shorter duration of respiratory support. It remains uncertain whether nitric oxide administered into the cardiopulmonary bypass oxygenator improves ventilator-free days (days alive and free from mechanical ventilation).

OBJECTIVE

To determine the effect of nitric oxide applied into the cardiopulmonary bypass oxygenator vs standard care on ventilator-free days in children undergoing surgery for congenital heart disease.

DESIGN, SETTING, AND PARTICIPANTS

Double-blind, multicenter, randomized clinical trial in 6 pediatric cardiac surgical centers in Australia, New Zealand, and the Netherlands. A total of 1371 children younger than 2 years undergoing congenital heart surgery were randomized between July 2017 and April 2021, with 28-day follow-up of the last participant completed on May 24, 2021.

INTERVENTIONS

Patients were assigned to receive nitric oxide at 20 ppm delivered into the cardiopulmonary bypass oxygenator (n = 679) or standard care cardiopulmonary bypass without nitric oxide (n = 685).

MAIN OUTCOMES AND MEASURES

The primary end point was the number of ventilator-free days from commencement of bypass until day 28. There were 4 secondary end points including a composite of low cardiac output syndrome, extracorporeal life support, or death; length of stay in the intensive care unit; length of stay in the hospital; and postoperative troponin levels.

RESULTS

Among 1371 patients who were randomized (mean [SD] age, 21.2 [23.5] weeks; 587 girls [42.8%]), 1364 (99.5%) completed the trial. The number of ventilator-free days did not differ significantly between the nitric oxide and standard care groups, with a median of 26.6 days (IQR, 24.4 to 27.4) vs 26.4 days (IQR, 24.0 to 27.2), respectively, for an absolute difference of -0.01 days (95% CI, -0.25 to 0.22; P = .92). A total of 22.5% of the nitric oxide group and 20.9% of the standard care group developed low cardiac output syndrome within 48 hours, needed extracorporeal support within 48 hours, or died by day 28, for an adjusted odds ratio of 1.12 (95% CI, 0.85 to 1.47). Other secondary outcomes were not significantly different between the groups.

CONCLUSIONS AND RELEVANCE

In children younger than 2 years undergoing cardiopulmonary bypass surgery for congenital heart disease, the use of nitric oxide via cardiopulmonary bypass did not significantly affect the number of ventilator-free days. These findings do not support the use of nitric oxide delivered into the cardiopulmonary bypass oxygenator during heart surgery.

TRIAL REGISTRATION

anzctr.org.au Identifier: ACTRN12617000821392.

Factors associated with admission of children to an intensive care unit and readmission to hospital within 28 days of discharge: A population-based study

AIM

Hospital readmissions within 28 days are an important performance measurement of quality and safety of health care. The aims of this study were to examine the rates, trends and characteristics of paediatric intensive care unit admissions, and factors associated with readmissions to hospital within 28 days of discharge.

METHODS

This retrospective, population-based record linkage study included all children ≥28 days and <16 years old admitted to an intensive care unit (ICU) in a New South Wales (NSW) public hospital from 2004 to 2013. Data were sourced from the NSW Admitted Patients Data Collection and the NSW Registry of Births, Deaths and Marriages, Death Registration.

RESULTS

We identified 21 200 ICU admissions involving 17 130 children. Admissions increased by 24% over the study period with the greatest increase attributed to respiratory and musculoskeletal conditions. A higher proportion of children were <5 years, male, lived in major cities, were publicly insured and had chronic conditions. The median length of ICU stay was 42 h and overall hospital stay was 7 days. There were 905 deaths, two-thirds during the index admission with the leading causes being injuries, cancer and infections. Twenty-three per cent of ICU admissions were readmitted to hospital within 28 days of discharge. Associated independent factors were younger age, longer index hospital stay and emergency index admission. Children with chronic conditions of cancer and genitourinary disorders were more likely to be readmitted.

CONCLUSIONS

Identification of complex chronic conditions, consideration of long-term health planning and interventions intended to reduce readmission is warranted in order to reduce the burden to families and the health-care system.

Retrieval of neonatal and paediatric patients on extracorporeal membrane oxygenation support in New South Wales, Australia

New South Wales has recently added the capability of extracorporeal membrane oxygenation to the neonatal and paediatric retrieval process and this paper describes the early experiences and protocol development for the first eight cases transported.

Priorities for paediatric critical care research: a modified Delphi study by the Australian and New Zealand Intensive Care Society Paediatric Study Group

Objective: Most interventions in paediatric critical care lack high grade evidence. We aimed to identify the key research priorities and key clinical outcome measures pertinent to research in paediatric intensive care patients. Design: Modified three-stage Delphi study combining staged online surveys, followed by a face-to-face discussion and final voting. Setting: Paediatric intensive care units in Australia and New Zealand. Participants: Medical and nursing staff working in intensive care. Main outcome measurements: Self-reported priorities for research. Results: 193 respondents provided a total of 267 research questions and 234 outcomes. In Stage 3, the top 56 research questions and 50 outcomes were discussed face to face, which allowed the identification of the top 20 research questions with the Hanlon prioritisation score and the top 20 outcomes. Topics centred on the use of intravenous fluids (restrictive v liberal fluids, use of fluid resuscitation bolus, early inotrope use, type of intravenous fluid, and assessment of fluid responsiveness), and patient- and family-centred outcomes (health-related quality of life, liberation) emerged as priorities. While mortality, length of stay, and organ support/organ dysfunction were considered important and the most feasible outcomes, long term quality of life and neurodevelopmental measures were rated highly in terms of their importance. Conclusions: Using a modified Delphi method, this study provides guidance towards prioritisation of research topics in paediatric critical care in Australia and New Zealand, and identifies study outcomes of key relevance to clinicians and experts in the field.

Ten Years of National Seasonal Surveillance for Severe Complications of Influenza in Australian Children

BACKGROUND

Severe complications of influenza in children are uncommon but may result in admission to hospital or an intensive care unit (ICU) and death.

METHODS

Active prospective surveillance using the Australian Paediatric Surveillance Unit with monthly reporting by pediatricians of national demographic and clinical data on children with <15 years of age hospitalized with severe complications of laboratory-confirmed influenza during ten influenza seasons 2008-2017.

RESULTS

Of 722 children notified, 613 had laboratory-confirmed influenza and at least one severe complication. Most (60%) were <5 years of age; 10% were <6 months, hence ineligible for vaccination. Almost half of all cases were admitted to ICU and 30 died. Most children were previously healthy: 40.3% had at least one underlying medical condition. Sixty-five different severe complications were reported; pneumonia was the most common, occurring in over half of all cases. Influenza A accounted for 68.6% hospitalizations; however, influenza B was more often associated with acute renal failure (P = 0.014), rhabdomyolysis (P = 0.019), myocarditis (P = 0.015), pericarditis (P = 0.013), and cardiomyopathy (P = 0.035). Children who died were more likely to be older (5-14 years), have underlying medical conditions, be admitted to ICU, and have encephalitis, acute renal failure, or myocarditis. Only 36.1% of all children reported received antiviral medications, and 8.5% were known to be vaccinated for seasonal influenza.

CONCLUSIONS

Severe influenza complications cause morbidity and mortality in children, which may increase if coinfection with COVID-19 occurs in the 2020 season and beyond. Increased vaccination rates, even in healthy children, early diagnosis and timely antiviral treatment are needed to reduce severe complications and death.

Statistical analysis plan for the NITric oxide during cardiopulmonary bypass to improve Recovery in Infants with Congenital heart defects (NITRIC) trial

Background: The NITric oxide during cardiopulmonary bypass (CPB) to improve Recovery in Infants with Congenital heart defects (NITRIC) trial, a 1320-patient, multicentre, randomised controlled trial, is aiming to improve survival free of ventilation after CPB by using nitric oxide delivered into the oxygenator of the CPB. Objective: To provide a statistical analysis plan before completion of patient recruitment and data monitoring. Final analyses for this study will adhere to this statistical analysis plan, which details all key pre-planned analyses. Stata scripts for analyses have been prepared alongside this statistical analysis plan. Methods: The statistical analysis plan was designed collaboratively by the chief investigators and trial statistician and builds on the previously published study protocol. All authors remain blinded to treatment allocation. Detail is provided on statistical analyses including cohort description, analysis of primary and secondary outcomes and adverse events. Statistical methods to compare outcomes are planned in detail to ensure methods are verifiable and reproducible. Results: The statistical analysis plan developed provides the trial outline, list of mock tables, and analysis scripts. The plan describes statistical analyses on cohort and baseline description, primary and secondary outcome analyses, process of care measures, physiological descriptors, and safety and adverse event reporting. We define the pre-specified subgroup analyses and the respective statistical tests used to compare subgroups. Conclusion: The statistical analysis plan for the NITRIC trial establishes detailed pre-planned analyses alongside Stata scripts to analyse the largest trial in the field of neonatal and paediatric heart surgery. The plan ensures standards for trial analysis validity aiming to minimise bias of analyses. Trial registration: ACTRN12617000821392.

Resuscitation in Paediatric Sepsis Using Metabolic Resuscitation-A Randomized Controlled Pilot Study in the Paediatric Intensive Care Unit (RESPOND PICU): Study Protocol and Analysis Plan

Introduction: Septic shock remains amongst the leading causes of childhood mortality. Therapeutic options to support children with septic shock refractory to initial resuscitation with fluids and inotropes are limited. Recently, the combination of intravenous hydrocortisone with high dose ascorbic acid and thiamine (HAT therapy), postulated to reduce sepsis-related organ dysfunction, has been proposed as a safe approach with potential for mortality benefit, but randomized trials in paediatric patients are lacking. We hypothesize that protocolised early use of HAT therapy ("metabolic resuscitation") in children with septic shock is feasible and will lead to earlier resolution of organ dysfunction. Here, we describe the protocol of the Resuscitation in Paediatric Sepsis Using Metabolic Resuscitation-A Randomized Controlled Pilot Study in the Paediatric Intensive Care Unit (RESPOND PICU). Methods and Analysis: The RESPOND PICU study is an open label randomized-controlled, two-sided multicentre pilot study conducted in paediatric intensive care units (PICUs) in Australia and New Zealand. Sixty children aged between 28 days and 18 years treated with inotropes for presumed septic shock will be randomized in a 1:1 ratio to either metabolic resuscitation (1 mg/kg hydrocortisone q6h, 30 mg/kg ascorbic acid q6h, 4 mg/kg thiamine q12h) or standard septic shock management. Main outcomes include feasibility of the study protocol and survival free of organ dysfunction censored at 28 days. The study cohort will be followed up at 28-days and 6-months post enrolment to assess neurodevelopment, quality of life and functional status. Biobanking will allow ancillary studies on sepsis biomarkers. Ethics and Dissemination: The study received ethical clearance from Children's Health Queensland Human Research Ethics Committee (HREC/18/QCHQ/49168) and commenced enrolment on June 12th, 2019. The primary study findings will be submitted for publication in a peer-reviewed journal. Trial Registration: Australian and New Zealand Clinical Trials Registry (ACTRN12619000829112). Protocol Version: V1.8 22/7/20.

Gestational Age and Risk of Mortality in Term-Born Critically Ill Neonates Admitted to PICUs in Australia and New Zealand

OBJECTIVES

Gestational age at birth is declining, probably because more deliveries are being induced. Gestational age is an important modifiable risk factor for neonatal mortality and morbidity. We aimed to investigate the association between gestational age and mortality in hospital for term-born neonates (≥ 37 wk') admitted to PICUs in Australia and New Zealand.

DESIGN

Observational multicenter cohort study.

SETTING

PICUs in Australia and New Zealand.

PATIENTS

Term-born neonates (≥ 37 wk) admitted to PICUs.

INTERVENTIONS

None MEASUREMENTS AND MAIN RESULTS:: We studied 5,073 infants born with a gestational age greater than or equal to 37 weeks and were less than 28 days old when admitted to a PICU in Australia or New Zealand between 2007 and 2016. The association between gestational age and mortality was estimated using a multivariable logistic regression model, adjusting for age, sex, indigenous status, Pediatric Index of Mortality version 2, and site. The median gestational age was 39.1 weeks (interquartile range, 38.2-40 wk) and mortality in hospital was 6.6%. Risk of mortality declined log-linearly with gestational age. The adjusted analysis showed a 20% (95% CI, 11-28%) relative reduction in mortality for each extra week of gestation beyond 37 weeks. The effect of gestation was stronger among those who received extracorporeal life support: each extra week of gestation was associated with a 44% (95% CI, 25-57%) relative reduction in mortality. Longer gestation was also associated with reduced length of stay in hospital: each week increase in gestation, the average length of stay decreased by 4% (95% CI, 2-6%).

CONCLUSIONS

Among neonates born at "term" who are admitted to a PICU, increasing gestational age at birth is associated with a substantial reduction in the risk of dying in hospital. The maturational influence on outcome was more strongly noted in the sickest neonates, such as those requiring extracorporeal life support. This information is important in view of the increasing proportion of planned births in both high- and low-/middle-income countries.

Defining benefit threshold for extracorporeal membrane oxygenation in children with sepsis-a binational multicenter cohort study

BACKGROUND

The surviving sepsis campaign recommends consideration for extracorporeal membrane oxygenation (ECMO) in refractory septic shock. We aimed to define the benefit threshold of ECMO in pediatric septic shock.

METHODS

Retrospective binational multicenter cohort study of all ICUs contributing to the Australian and New Zealand Paediatric Intensive Care Registry. We included patients < 16 years admitted to ICU with sepsis and septic shock between 2002 and 2016. Sepsis-specific risk-adjusted models to establish ECMO benefit thresholds with mortality as the primary outcome were performed. Models were based on clinical variables available early after admission to ICU. Multivariate analyses were performed to identify predictors of survival in children treated with ECMO.

RESULTS

Five thousand sixty-two children with sepsis and septic shock met eligibility criteria, of which 80 (1.6%) were treated with veno-arterial ECMO. A model based on 12 clinical variables predicted mortality with an AUROC of 0.879 (95% CI 0.864-0.895). The benefit threshold was calculated as 47.1% predicted risk of mortality. The observed mortality for children treated with ECMO below the threshold was 41.8% (23 deaths), compared to a predicted mortality of 30.0% as per the baseline model (16.5 deaths; standardized mortality rate 1.40, 95% CI 0.89-2.09). Among patients above the benefit threshold, the observed mortality was 52.0% (13 deaths) compared to 68.2% as per the baseline model (16.5 deaths; standardized mortality rate 0.61, 95% CI 0.39-0.92). Multivariable analyses identified lower lactate, the absence of cardiac arrest prior to ECMO, and the central cannulation (OR 0.31, 95% CI 0.10-0.98, p = 0.046) as significant predictors of survival for those treated with VA-ECMO.

CONCLUSIONS

This binational study demonstrates that a rapidly available sepsis mortality prediction model can define thresholds for survival benefit in children with septic shock considered for ECMO. Survival on ECMO was associated with central cannulation. Our findings suggest that a fully powered RCT on ECMO in sepsis is unlikely to be feasible.

Study protocol: NITric oxide during cardiopulmonary bypass to improve Recovery in Infants with Congenital heart defects (NITRIC trial): a randomised controlled trial

INTRODUCTION

Congenital heart disease (CHD) is a major cause of infant mortality. Many infants with CHD require corrective surgery with most operations requiring cardiopulmonary bypass (CPB). CPB triggers a systemic inflammatory response which is associated with low cardiac output syndrome (LCOS), postoperative morbidity and mortality. Delivery of nitric oxide (NO) into CPB circuits can provide myocardial protection and reduce bypass-induced inflammation, leading to less LCOS and improved recovery. We hypothesised that using NO during CPB increases ventilator-free days (VFD) (the number of days patients spend alive and free from invasive mechanical ventilation up until day 28) compared with standard care. Here, we describe the NITRIC trial protocol.

METHODS AND ANALYSIS

The NITRIC trial is a randomised, double-blind, controlled, parallel-group, two-sided superiority trial to be conducted in six paediatric cardiac surgical centres. One thousand three-hundred and twenty infants <2 years of age undergoing cardiac surgery with CPB will be randomly assigned to NO at 20 ppm administered into the CPB oxygenator for the duration of CPB or standard care (no NO) in a 1:1 ratio with stratification by age (<6 and ≥6 weeks), single ventricle physiology (Y/N) and study centre. The primary outcome will be VFD to day 28. Secondary outcomes include a composite of LCOS, need for extracorporeal membrane oxygenation or death within 28 days of surgery; length of stay in intensive care and in hospital; and, healthcare costs. Analyses will be conducted on an intention-to-treat basis. Preplanned secondary analyses will investigate the impact of NO on host inflammatory profiles postsurgery.

ETHICS AND DISSEMINATION

The study has ethical approval (HREC/17/QRCH/43, dated 26 April 2017), is registered in the Australian New Zealand Clinical Trials Registry (ACTRN12617000821392) and commenced recruitment in July 2017. The primary manuscript will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ACTRN12617000821392.

Transnasal Humidified Rapid Insufflation Ventilatory Exchange in children requiring emergent intubation (Kids THRIVE): a protocol for a randomised controlled trial

INTRODUCTION

Emergency intubation of children with abnormal respiratory or cardiac physiology is a high-risk procedure and associated with a high incidence of adverse events including hypoxemia. Successful emergency intubation is dependent on inter-related patient and operator factors. Preoxygenation has been used to maximise oxygen reserves in the patient and to prolong the safe apnoeic time during the intubation phase. Transnasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) prolongs the safe apnoeic window for a safe intubation during elective intubation. We designed a clinical trial to test the hypothesis that THRIVE reduces the frequency of adverse and hypoxemic events during emergency intubation in children and to test the hypothesis that this treatment is cost-effective compared with standard care.

METHODS AND ANALYSIS

The Kids THRIVE trial is a multicentre randomised controlled trial performed in participating emergency departments and paediatric intensive care units. 960 infants and children aged 0-16 years requiring emergency intubation for all reasons will be enrolled and allocated to THRIVE or control in a 1:1 allocation with stratification by site, age (<1, 1-7 and >7 years) and operator (junior and senior). Children allocated to THRIVE will receive weight appropriate transnasal flow rates with 100% oxygen, whereas children in the control arm will not receive any transnasal oxygen insufflation. The primary outcomes are defined as follows: (1) hypoxemic event during the intubation phase defined as SpO₂ <90% (patient-dependent variable) and (2) first intubation attempt success without hypoxemia (operator-dependent variable). Analyses will be conducted on an intention-to-treat basis.

ETHICS AND DISSEMINATION

Ethics approval for the protocol and consent process has been obtained (HREC/16/QRCH/81). The trial has been actively recruiting since May 2017. The study findings will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ACTRN12617000147381.

A cluster randomised, crossover, registry-embedded clinical trial of proton pump inhibitors versus histamine-2 receptor blockers for ulcer prophylaxis therapy in the intensive care unit (PEPTIC study): study protocol

BACKGROUND

The balance of risks and benefits with using proton pump inhibitors (PPIs) versus histamine-2 receptor blockers (H₂RB) for stress ulcer prophylaxis in patients who are invasively ventilated in the intensive care unit (ICU) is uncertain.

OBJECTIVE

To describe the study protocol and statistical analysis plan for the Proton Pump Inhibitors versus Histamine-2 Receptor Blockers for Ulcer Prophylaxis Therapy in the Intensive Care Unit (PEPTIC) study.

DESIGN, SETTING AND PARTICIPANTS

Protocol for a prospective, multicentre, randomised, open-label, cluster crossover, registry-embedded trial to be conducted in 50 ICUs in Australia, Canada, Ireland, New Zealand and the United Kingdom. The PEPTIC study will compare two approaches to stress ulcer prophylaxis in mechanically ventilated adults implemented at the level of the ICU. One approach is to use PPIs as the default therapy and the other approach is to use H2RBs as the default therapy when stress ulcer prophylaxis is prescribed. Each ICU, by random allocation, will use one approach for 6 months and will then switch to the opposite approach for the next 6 months. The PEPTIC study began recruitment in August 2016 and will complete recruitment in January 2019.

MAIN OUTCOME MEASURES

The primary end point will be in-hospital mortality. Secondary outcomes include clinically significant upper gastrointestinal bleeding, Clostridium difficile infection, ICU length of stay and hospital length of stay.

RESULTS AND CONCLUSIONS

The PEPTIC study will compare the effect on in-hospital mortality of implementing, at the level of the ICU, the use of PPI as the preferred agent for stress ulcer prophylaxis in mechanically ventilated adults in the ICU with using H₂RB as the preferred agent.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry (ANZCTRN 12616000481471).

Fluid bolus therapy in critically ill children: a survey of practice among paediatric intensive care doctors in Australia and New Zealand

OBJECTIVE

Fluid bolus therapy (FBT) is a widely used intervention in paediatric critical illness. The aim of this study was to describe the attitudes and practices towards FBT of paediatric intensive care doctors in Australia and New Zealand.

DESIGN

An internet-based survey of paediatric intensive care doctors in Australia and New Zealand between 7 and 30 November 2016.

SETTING

Paediatric intensive care units with greater than 400 admissions annually.

PARTICIPANTS

Paediatric intensive care specialists and junior medical staff.

MAIN OUTCOME MEASURES

Preferences for FBT and markers of fluid responsiveness.

RESULTS

There were 106/175 respondents (61%); 0.9% saline and 4% albumin are used frequently or almost always by 86% and 57% of respondents respectively. The preferred volume and duration were 10 mL/kg in less than 10 minutes. The highest rated markers of fluid responsiveness were heart rate and blood pressure - rated as "good" or "very good" by 75% and 58% of respondents respectively. Central venous saturations and serum lactate were the highest rated biochemical markers. The most frequently expected magnitude of change for heart rate and blood pressure was 6-15% by 89% and 76% of respondents respectively. The preferred fluid composition for sepsis, trauma, traumatic brain injury and acute lung injury was 0.9% saline, and 4% albumin for post-operative cardiac surgery.

CONCLUSIONS

Paediatric intensive care doctors prefer 0.9% saline and 4% albumin for FBT. Heart rate and blood pressure are the most preferred markers to assess fluid responsiveness. Preferences for FBT in specific conditions exist.

The burden of invasive infections in critically ill Indigenous children in Australia

OBJECTIVES

To describe the incidence and mortality of invasive infections in Indigenous children admitted to paediatric and general intensive care units (ICUs) in Australia.

DESIGN

Retrospective multi-centre cohort study of Australian and New Zealand Paediatric Intensive Care Registry data.

PARTICIPANTS

All children under 16 years of age admitted to an ICU in Australia, 1 January 2002 - 31 December 2013. Indigenous children were defined as those identified as Aboriginal and/or Torres Strait Islander in a mandatory admissions dataset.

MAIN OUTCOMES

Population-based ICU mortality and admission rates.

RESULTS

Invasive infections accounted for 23.0% of non-elective ICU admissions of Indigenous children (726 of 3150), resulting in an admission rate of 47.6 per 100 000 children per year. Staphylococcus aureus was the leading pathogen identified in children with sepsis/septic shock (incidence, 4.42 per 100 000 Indigenous children per year; 0.57 per 100 000 non-Indigenous children per year; incidence rate ratio 7.7; 95% CI, 5.8-10.1; P < 0.001). While crude and risk-adjusted ICU mortality related to invasive infections was not significantly different for Indigenous and non-Indigenous children (odds ratio, 0.75; 95% CI, 0.53-1.07; P = 0.12), the estimated population-based age-standardised mortality rate for invasive infections was significantly higher for Indigenous children (2.67 per 100 000 per year v 1.04 per 100 000 per year; crude incidence rate ratio, 2.65; 95% CI, 1.88-3.64; P < 0.001).

CONCLUSIONS

The ICU admission rate for severe infections was several times higher for Indigenous than for non-Indigenous children, particularly for S. aureus infections. While ICU case fatality rates were similar, the population-based mortality was more than twice as high for Indigenous children. Our study highlights an important area of inequality in health care for Indigenous children in a high income country that needs urgent attention.

Maintenance fluid practices in paediatric intensive care units in Australia and New Zealand

BACKGROUND

Maintenance fluid administration is a common practice in paediatric intensive care units (PICUs), contributing to daily fluid intake and fluid balance, but little is known about this practice.

OBJECTIVES

To determine the volume and type of maintenance fluid delivered to PICU patients, and to assess changes in practice compared with a previous time point.

METHODS

A prospective, observational, single-day, point prevalence study of paediatric patients from 11 Australian and New Zealand PICUs, conducted in 2014.

RESULTS

Seventy-two patients were enrolled. The median age and weight of infants aged < 1 year (n = 34) were 2 months (interquartile range [IQR],1-4) and 5 kg (IQR, 4-6), respectively; while in children ≥ 1 year of age (n = 38), these were 4 years (IQR, 2-8) and 17 kg (IQR, 12-23), respectively. On the study day, 19 infants (56%) and 19 children aged ≥ 1 year (50%) received maintenance fluids. Infants received a median of 23 mL/kg (IQR, 12-45) of maintenance fluid in addition to 51 mL/kg (IQR, 40-72) of fluid and nutrition from other sources; maintenance fluids contributed 29% (IQR, 13%-60%) of the total daily fluid intake. Children ≥ 1 year of age received a median of 18 mL/kg (IQR, 9-37) of maintenance fluid in addition to 39 mL/kg (IQR, 25-53) of fluid and nutrition from other sources; maintenance fluids contributed 33% (IQR, 17%-69%) of the total daily fluid intake. When compared with similar data from 2011, there was no change in the amount of maintenance fluid given, which was administered mostly as isotonic fluids.

CONCLUSION

Maintenance fluid contributes about a third of total fluid administration in children in Australian and New Zealand PICUs and is mostly administered as isotonic solutions.

The Australian and New Zealand Intensive Care Society Clinical Trials Group point prevalence program, 2009-2016

BACKGROUND

Cross-sectional point prevalence studies collect observational data at a single time point and may be used to facilitate subsequent research hypotheses and discovery.

METHODS

We report the process of implementation and substantive outputs of the Australian and New Zealand Intensive Care Society Clinical Trials Group (ANZICS CTG) point prevalence program, conducted in participating intensive care units from 2009 to 2016.

RESULTS

Seventy-seven of a maximum 197 adult ICUs across Australia and New Zealand participated in 9 specified study days over 18 days of data collection and collected data on 5043 participants, with an average of 44 ICUs per study day. All eight Australian and New Zealand paediatric ICUs have participated in dedicated simultaneous paediatric study days. Thirteen manuscripts were published in peer-reviewed journals and data have contributed to 14 individual programs of research, including 18 subsequent grant applications for further research.

CONCLUSION

The ANZICS CTG point prevalence program has resulted in the collection of a substantial body of observational data that has facilitated the development and completion of subsequent research programs and provided opportunities for subsequent capacity development.

Prediction of pediatric sepsis mortality within 1 h of intensive care admission

PURPOSE

The definitions of sepsis and septic shock have recently been revised in adults, but contemporary data are needed to inform similar approaches in children.

METHODS

Multicenter cohort study including children <16 years admitted with sepsis or septic shock to ICUs in Australia and New Zealand in the period 2012-2015. We assessed septic shock criteria at ICU admission to define sepsis severity, using 30-day mortality as outcome. Through multivariable logistic regression, a pediatric sepsis score was derived using variables available within 60 min of ICU admission.

RESULTS

Of 42,523 pediatric admissions, 4403 children were admitted with invasive infection, including 1697 diagnosed as having sepsis/septic shock on admission. Mortality was 8.5% (144/1697) and 50.7% of deaths occurred within 48 h of admission. The presence of septic shock as defined by the 2005 consensus was sensitive but not specific in predicting mortality (AUC = 0.69; 95% CI 0.65-0.72). Combinations of hypotension, vasopressor therapy, and lactate >2 mmol/l discriminated poorly (AUC <0.60). Multivariate models showed that oxygenation markers, ventilatory support, hypotension, cardiac arrest, serum lactate, pupil responsiveness, and immunosuppression were the best-performing predictors (0.843; 0.811-0.875). We derived a pediatric sepsis score (0.817; 0.779-0.855), and every one-point increase was associated with a 28.5% (23.8-33.2%) increase in the odds of death. Children with a score ≥6 had 19.8% mortality and accounted for 74.3% of deaths. The sepsis score performed comparably when applied to all children admitted with invasive infection (0.810; 0.781-0.840).

CONCLUSIONS

We observed mortality patterns specific to pediatric sepsis that support the need for specialized definitions of sepsis severity in children. We demonstrated the importance of lactate, cardiovascular, and respiratory derangements at ICU admission for the identification of children with substantially higher risk of sepsis mortality.

Using the plant vacuole as a biological system to investigate the functional properties of exogenous channels and transporters

Plant cells possess a large intracellular compartment that animal cells do not, the central vacuole, which has been investigated for a long time. The central vacuole can occupy up to 90% of the cellular volume and, differently from intracellular organelles from animal cells such as lysosomes or endosomes, it is easy to isolate. Because of its large dimension (up to 40 μm diameter) it can be successfully studied using the classical patch-clamp technique. Following the idea that the vacuolar membrane could be used as a convenient model to characterize the functional properties of channel-forming peptides, we verified that the phytotoxic lipodepsipeptide Syringopeptin 25A from Pseudomonas syringae pv syringae was able to form ionic pores in sugar beet vacuoles and we performed a detailed biophysical analysis. Recently, we extended the use of plant vacuoles to the expression and functional characterization of animal intracellular transporters, namely rat CLC-7, and channels, i.e. human TPC2. Since endo-lysosomal transporters and channels are still largely unexplored, principally because their intracellular localization renders them difficult to study, we believe that this novel approach will prove to be a powerful system for the investigation of the molecular mechanisms of exogenous transporters and channels. This article is part of a Special Issue entitled: Pore-Forming Toxins edited by Mauro Dalla Serra and Franco Gambale.

BAG3 regulates formation of the SNARE complex and insulin secretion

Insulin release in response to glucose stimulation requires exocytosis of insulin-containing granules. Glucose stimulation of beta cells leads to focal adhesion kinase (FAK) phosphorylation, which acts on the Rho family proteins (Rho, Rac and Cdc42) that direct F-actin remodeling. This process requires docking and fusion of secretory vesicles to the release sites at the plasma membrane and is a complex mechanism that is mediated by SNAREs. This transiently disrupts the F-actin barrier and allows the redistribution of the insulin-containing granules to more peripheral regions of the β cell, hence facilitating insulin secretion. In this manuscript, we show for the first time that BAG3 plays an important role in this process. We show that BAG3 downregulation results in increased insulin secretion in response to glucose stimulation and in disruption of the F-actin network. Moreover, we show that BAG3 binds to SNAP-25 and syntaxin-1, two components of the t-SNARE complex preventing the interaction between SNAP-25 and syntaxin-1. Upon glucose stimulation BAG3 is phosphorylated by FAK and dissociates from SNAP-25 allowing the formation of the SNARE complex, destabilization of the F-actin network and insulin release.

Mortality related to invasive infections, sepsis, and septic shock in critically ill children in Australia and New Zealand, 2002-13: a multicentre retrospective cohort study

BACKGROUND

Severe infections kill more than 4·5 million children every year. Population-based data for severe infections in children requiring admission to intensive care units (ICUs) are scarce. We assessed changes in incidence and mortality of severe infections in critically ill children in Australia and New Zealand.

METHODS

We did a retrospective multicentre cohort study of children requiring intensive care in Australia and New Zealand between 2002 and 2013, with data from the Australian and New Zealand Paediatric Intensive Care Registry. We included children younger than 16 years with invasive infection, sepsis, or septic shock. We assessed incidence and mortality in the ICU for 2002-07 versus 2008-13.

FINDINGS

During the study period, 97 127 children were admitted to ICUs, 11 574 (11·9%) had severe infections, including 6688 (6·9%) with invasive infections, 2847 (2·9%) with sepsis, and 2039 (2·1%) with septic shock. Age-standardised incidence increased each year by an average of 0·56 cases per 100 000 children (95% CI 0·41-0·71) for invasive infections, 0·09 cases per 100 000 children (0·00-0·17) for sepsis, and 0·08 cases per 100 000 children (0·04-0·12) for septic shock. 260 (3·9%) of 6688 patients with invasive infection died, 159 (5·6%) of 2847 with sepsis died, and 346 (17·0%) of 2039 with septic shock died, compared with 2893 (3·0%) of all paediatric ICU admissions. Children admitted with invasive infections, sepsis, and septic shock accounted for 765 (26·4%) of 2893 paediatric deaths in ICUs. Comparing 2008-13 with 2002-07, risk-adjusted mortality decreased significantly for invasive infections (odds ratio 0·72, 95% CI 0·56-0·94; p=0·016), and for sepsis (0·66, 0·47-0·93; p=0·016), but not significantly for septic shock (0·79, 0·61-1·01; p=0·065).

INTERPRETATION

Severe infections remain a major cause of mortality in paediatric ICUs, representing a major public health problem. Future studies should focus on patients with the highest risk of poor outcome, and assess the effectiveness of present sepsis interventions in children.

FUNDING

National Medical Health and Research Council, Australian Resuscitation Outcomes Consortium, Centre of Research Excellence (1029983).

Expert and competent non-expert visual cues during simulated diagnosis in intensive care

The aim of this study was to examine the information acquisition strategies of expert and competent non-expert intensive care physicians during two simulated diagnostic scenarios involving respiratory distress in an infant. Specifically, the information acquisition performance of six experts and 12 competent non-experts was examined using an eye-tracker during the initial 90 s of the assessment of the patient. The results indicated that, in comparison to competent non-experts, experts recorded longer mean fixations, irrespective of the scenario. When the dwell times were examined against specific areas of interest, the results revealed that competent non-experts recorded greater overall dwell times on the nurse, where experts recorded relatively greater dwell times on the head and face of the manikin. In the context of the scenarios, experts recorded differential dwell times, spending relatively more time on the head and face during the seizure scenario than during the coughing scenario. The differences evident between experts and competent non-experts were interpreted as evidence of the relative availability of task-specific cues or heuristics in memory that might direct the process of information acquisition amongst expert physicians. The implications are discussed for the training and assessment of diagnostic skills.

Sodium administration in critically ill paediatric patients in Australia and New Zealand: a multicentre point prevalence study

OBJECTIVE

Dysnatraemia and a positive fluid balance are associated with poor outcomes in paediatric intensive care units (PICUs). Our objective was to determine sodium intake and the total daily fluid balance in children in the PICU.

METHOD

A single-day point prevalence study in 10 Australian and New Zealand PICUs. Patients on free oral diets were excluded. Demographics, 24-hour fluid balance and sodium intake (enteral and parenteral sources) were recorded.

RESULTS

We enrolled 65 patients; 15 were excluded due to having a free oral intake and two patients had incomplete data, leaving 48 children in the study cohort. The 21 infants had a median age of 4 months (interquartile range [IQR], 1-7 months) and a median bodyweight of 5 kg (IQR, 3.5- 6.1 kg). The 27 children > 1 year had a median age of 3 years (IQR, 1.5-13 years) and a median bodyweight of 17 kg (IQR, 9.5-47.5 kg). Overall, the median sodium administration on the study day was 4.9mmol/kg (IQR, 3.2- 8mmol/kg), median fluid administration was 80.8mL/kg (IQR, 49.8-111.4mL/kg) and median fluid balance was 9mL/kg (IQR, -1.4 to 41 mL/kg). For infants, the median sodium administration was 6mmol/kg (IQR, 3.9-8.1mmol/ kg), and median fluid balance was 20.8mL/kg (IQR, 3.5- 47.2mL/kg). For children > 1 year, the median sodium administration was 3.5mmol/kg (IQR, 3.1-7.8mmol/kg), and median fluid balance was 5.3mL/kg (IQR, -2.7 to 17.7mL/kg). Overall, fluid infusions, boluses and catheter flushes together contributed 46.2% of total sodium administered. Drugs contributed substantially to administered sodium (33.3%), with antibiotics accounting for the majority. Enteral feeds contributed 16.2% to overall administered sodium, and were the major source in patients in the PICU for > 10 days.

CONCLUSION

Daily sodium intake in children in the PICU is high. The contributions of maintenance and bolus intravenous fluids (most commonly as 0.9% sodium chloride), drug infusions and boluses, including antibiotics, and enteral feeds, are significant.

The capability of static and dynamic features to distinguish competent from genuinely expert practitioners in pediatric diagnosis

OBJECTIVE

The authors describe the development of a new, more objective method of distinguishing experienced competent nonexpert from expert practitioners within pediatric intensive care.

BACKGROUND

Expert performance involves the acquisition and use of refined feature-event associations (cues) in the operational environment. Competent non-experts, although experienced, possess rudimentary cue associations in memory. Thus, they cannot respond as efficiently or as reliably as their expert counterparts, particularly when key diagnostic information is unavailable, such as that provided by dynamic cues.

METHOD

This study involved the application of four distinct tasks in which the use of relevant cues could be expected to increase both the accuracy and the efficiency of diagnostic performance. These tasks included both static and dynamic stimuli that were varied systematically. A total of 50 experienced pediatric intensive staff took part in the study.

RESULTS

The sample clustered into two levels across the tasks: Participants who performed at a consistently high level throughout the four tasks were labeled experts, and participants who performed at a lower level throughout the tasks were labeled competent nonexperts. The groups differed in their responses to the diagnostic scenarios presented in two of the tasks and their ability to maintain performance in the absence of dynamic features.

CONCLUSION

Experienced pediatricians can be decomposed into two groups on the basis of their capacity to acquire and use cues; these groups differ in their diagnostic accuracy and in their ability to maintain performance in the absence of dynamic features.

APPLICATION

The tasks may be used to identify practitioners who are failing to acquire expertise at a rate consistent with their experience, position, or training. This information may be used to guide targeted training efforts.

The involvement of xanthohumol in the expression of annexin in human malignant glioblastoma cells

Glioblastoma multiforme (GBM) is the most common malignant and resistant tumor of the central nervous system in humans and new therapeutic strategies are urgently required. Recently, we have shown that the potential chemotherapeutic polyphenol xanthohumol (XH), isolated from Humulus Lupulus, induces apoptosis of human T98G glioblastoma cells by increasing reactive oxygen species and activating MAPK pathways. Then we have found, by western blotting and microscopic analysis, that XH up-regulates cytosolic levels of ANXA1 and induces translocation of the protein on the cell membrane of T98G cells in a time-dependent manner with significant effects observed after 24 h. On the basis of the above evidence, the aim of this work was to investigate the role of intracellular and cell membrane localized ANXA1 in GBM cells. RT-PCR analysis has shown that XH up-regulates mRNA levels of ANXA1 after 16 h treatment. To demonstrate the involvement of ANXA1 in apoptosis of GBM cells we down-regulated ANXA1 expression with small interfering RNA (siRNA) and then analysed apoptosis in the presence and absence of apoptotic stimuli. Importantly, apoptosis induced by XH was reduced in siRNA-ANXA1 transfected cells where western blot analysis shows a significant reduction of ANXA1 protein levels. To investigate the role of ANXA1 expression on the cell membrane of T98G cells as potential "eat-me" signal we studied phagocytosis of apoptotic cells by human macrophages. We incubated apoptotic T98G cells with human blood monocyte derived macrophages (M=). After co-incubation period we analysed the percentage of M= phagocytosing the apoptotic cells by cytofluorimetric FACS analysis and by confocal microscopy. Our results show that XH induces phagocytosis of apoptotic T98G cells by human M= in a concentration-effect manner, a processes that is dependent on caspase mediated apoptosis. ANXA1 acts as an "eat-me" signal on the cell membrane of T98G cells, and interestingly, apoptotic siRNA-ANXA1 transfected cells are not completely ingested by M=. These results were confirmed by incubating apoptotic cells with a neutralizing anti-ANXA1 antiboby and ANXA1 membrane depletion by EDTA washing. ANXA1 was also detected in supernatants of apoptotic cells and the incubation of enriched supernatants enhanced the percentage of phagocytosis by M=. These results demonstrated that ANXA1 is involved both in the apoptosis and phagocytosis of glioblastoma cells. This study shows a possible role of ANXA1 in maintenance of brain homeostasis and may lead to novel therapeutic approaches for neuro-inflammatory diseases and chemotherapy targets in the treatment of glioblastoma multiforme.

Pandemic H1N1 in children requiring intensive care in Australia and New Zealand during winter 2009

OBJECTIVE

To describe in detail the pediatric intensive care experience of influenza A, particularly pandemic H1N1-09, in Australia and New Zealand during the 2009 Southern Hemisphere winter and to compare the pediatric experience with that of adults.

METHOD

This was an inception-cohort study of all children who were admitted to intensive care with confirmed influenza A during winter 2009 at all general ICUs and PICUs in Australia and New Zealand.

RESULTS

From June 1 through August 31, 2009, 107 children (20.0 per million [95% confidence interval: 16.1-23.8]) with influenza A, including 83 (15.5 per million [95% confidence interval: 12.1-18.9]) with H1N1-09 were admitted to ICUs. Fifty-two percent (39 of 75) of children with H1N1-09 had 1 or more comorbidity, most commonly neurologic (20%). Most (48 of 83 [58%]) presented with pneumonia. Thirteen of 83 (16%) had neurologic presentations. Eighty percent of the children with H1N1-09 required ventilation. Mortality was lower than in adults: 6 of 83 (7%) vs 114 of 668 (17%) (P = .02). The median length of stay for children with H1N1-09 was 5 days. Children with H1N1-09 occupied 773 bed-days (147 per million children) and 5.8% of specialist PICU beds. Presentation with septic shock or after cardiac arrest and the presence of 1 or more comorbidities were risk factors for severe disease.

CONCLUSIONS

H1N1-09 caused a substantial burden on pediatric intensive care services in Australia and New Zealand. Compared with adults, children more commonly had nonrespiratory presentations and required ventilation more often but had a lower mortality rate.

The activity of hsp90 alpha promoter is regulated by NF-kappa B transcription factors

Heat-shock proteins (HSP) 90 exert a relevant role in the survival and response to therapy of many neoplastic cell types. Here, we show that the promoter of hsp90alpha gene, that encodes the inducible form of HSP90, is regulated by nuclear factor-kappaB (NF-kappaB) activity. Indeed, we found that NF-kappaB factors bound to one of the two putative consensus sequences present in the hsp90alpha-flanking region; mutation of such motif hampered the phorbol-myristate-13-acetate-stimulated expression of a luciferase reporter gene under the control of the hsp90alpha promoter. Furthermore, the downmodulation of NF-kappaB (p65) levels by a specific small interfering (si) RNA resulted in reducing the levels of endogenous HSP90alpha protein. These findings disclose a previously unrecognized mechanism that contributes to connect NF-kappaB factors and HSPs in cell defence machinery.

Annexin-1 downregulation in thyroid cancer correlates to the degree of tumor differentiation

We investigated the expression of annexin-1 (ANXA1) in thyroid carcinoma cell lines and in thyroid cancers with a different degree of differentiation. The highest level of ANXA1 expression examined by Western blotting was detected in the papillary carcinoma cells (NPA) and in the follicular cells (WRO). On the other hand, the most undifferentiated thyroid carcinoma cells (ARO and FRO) presented the lowest level of ANXA1 expression. In surgical tissue specimens from 32 patients with thyroid cancers, we found high immunoreactivity for ANXA1 in papillary (PTC) and follicular (FTC) thyroid cancers while in undifferentiated thyroid cancers (UTC) the expression of the protein was barely detectable. Control thyroid tissue resulted positive for ANXA1. In summary, 70% of UTC examined weakly expressed ANXA1, whereas 65% of PTC or FTC specimens tested showed high expression of the protein. Thus ANXA1 expression may correlate with the tumorigenesis suggesting that the protein may represent an effective differentiation marker in thyroid cancer.

Post-translational modification plays an essential role in the translocation of annexin A1 from the cytoplasm to the cell surface

Annexin A1 (ANXA1) has an important role in cell-cell communication in the host defense and neuroendocrine systems. In both systems, its actions are exerted extracellularly via membrane-bound receptors on adjacent sites after translocation of the protein from the cytoplasm to the cell surface of adjacent cells. This study used molecular, microscopic, and pharmacological approaches to explore the mechanisms underlying the cellular exportation of ANXA1 in TtT/GF (pituitary folliculo-stellate) cells. LPS caused serine-phosphorylation of ANXA1 (ANXA1-S27-PO4) and translocation of the phosphorylated protein to the cell membrane. The fundamental requirement of phosphorylation for membrane translocation was confirmed by immunofluorescence microscopy on cells transfected with wild-type or mutated (S27/A) ANXA1 constructs tagged with enhanced green fluorescence protein. The trafficking of ANXA1-S27-PO4 to the cell surface was dependent on PI3-kinase and MAP-kinase. It also required HMG-coenzyme A and myristoylation. The effects of HMG-coenzyme A blockade were overcome by mevalonic acid (the product of HMG-coenzyme A) and farnesyl-pyrophosphate but not by geranyl-geranylpyrophosphate or cholesterol. Together, these results suggest that serine-27 phosphorylation is essential for the translocation of ANXA1 across the cell membrane and also identify a role for isoprenyl lipids. Such lipids could target consensus sequences in ANXA1. Alternatively, they may target other proteins in the signal transduction cascade (e.g., transporters).

Clinical assessment of cardiac performance in infants and children following cardiac surgery

OBJECTIVE

To compare clinical assessment of cardiac performance with an invasive method of haemodynamic monitoring.

DESIGN AND SETTING

Prospective observational study in a 16-bed tertiary paediatric intensive care unit.

PATIENTS AND PARTICIPANTS

Infants and children undergoing cardiopulmonary bypass and surgical repair of congenital heart lesions.

INTERVENTIONS

Based on physical examination and routinely available haemodynamic monitoring in the paediatric intensive care unit, medical and nursing staff assessed cardiac index, systemic vascular resistance index and volume status. Clinical assessment was compared with cardiac index, systemic vascular resistance index and global end diastolic volume index, obtained by femoral artery thermodilution.

MEASUREMENTS AND RESULTS

A total of 76 clinical estimations of the three parameters were made in 16 infants and children undergoing biventricular repair of congenital heart lesions. Agreement was poor between clinical and invasive methods of determining all three studied parameters of cardiac performance. Cardiac index was significantly underestimated clinically; mean difference was 0.71 l min(-1) m(-2) (95% range of agreement +/-2.7). Clinical estimates of systemic vascular resistance (weighted kappa=0.15) and volume status (weighted kappa=0.04) showed poor levels of agreement with measured values and were overestimated clinically. There was one complication related to a femoral arterial catheter and one device failure.

CONCLUSIONS

Routine clinical assessment of parameters of cardiac performance agreed poorly with invasive determinations of these indices. Management decisions based on inaccurate clinical assessments may be detrimental to patients. Invasive haemodynamic monitoring using femoral artery thermodilution warrants cautious further evaluation as there is little agreement with clinical assessment which is presently standard accepted care in this patient population.

Outcome of children with neuromuscular disease admitted to paediatric intensive care

AIMS

To determine the outcome of children with neuromuscular disease (NMD) following admission to a tertiary referral paediatric intensive care (PICU).

METHODS

All children with chronic NMD whose first PICU admission was between July 1986 and June 2001 were followed up from their first PICU admission to time of study. The outcomes recorded were death in or outside of PICU, duration of PICU admission, artificial ventilation during admission and following discharge from PICU, and readmission to PICU.

RESULTS

Over 15 years, 28 children were admitted on 69 occasions. Sixteen (57%) children had more than one admission. The median duration of PICU admission was 4 days (range 0.5-42). Twenty three per cent of unplanned admissions resulted in the commencement of respiratory support that was continued after discharge from the PICU. Severity of functional impairment was not associated with longer duration of stay or higher PRISM scores. Ten children (36%) died, with four (14%) deaths in the PICU. A higher proportion of children with severe limitation of function were among children that died compared to survivors.

CONCLUSION

Most children with NMD admitted to the PICU recover and are discharged without the need for prolonged invasive ventilation. However, in this group of children, the use of non-invasive home based ventilation is common and they are likely to require further PICU admission.