Comprehensive Characterization of Surface-Bound Proteins and Measurement of Fibrin Fiber Thickness on Extracorporeal Membrane Oxygenation Circuits Collected From Patients.

OBJECTIVE: To characterize surface-bound proteins and to measure the thickness of fibrin fibers bound to extracorporeal membrane oxygenation (ECMO) circuits used in children. DESIGN: Single-center observational prospective study, April to November 2021. SETTING: PICU, Royal Children's Hospital, Melbourne, Australia. PATIENTS: Patients aged less than 18 years on venoarterial ECMO and without preexisting disorder. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: ECMO circuits were collected from six patients. Circuit samples were collected from five different sites, and subsequently processed for proteomic and scanning electron microscopy (SEM) studies. The concentration of proteins bound to ECMO circuit samples was measured using a bicinchoninic acid protein assay, whereas characterization of the bound proteome was performed using data-independent acquisition mass spectrometry. The Reactome Over-representation Pathway Analyses tool was used to identify functional pathways related to bound proteins. For the SEM studies, ECMO circuit samples were prepared and imaged, and the thickness of bound fibrin fibers was measured using the Fiji ImageJ software, version 1.53c (https://imagej.net/software/fiji/). Protein binding to ECMO circuit samples and fibrin networks showed significant intra-circuit and interpatient variation. The median (range) total protein concentration was 19.0 (0-76.9) µg/mL, and the median total number of proteins was 2011 (1435-2777). A total of 933 proteins were commonly bound to ECMO circuit samples from all patients and were functionally involved in 212 pathways, with signal transduction, cell cycle, and metabolism of proteins being the top three pathway categories. The median intra-circuit fibrin fiber thickness was 0.20 (0.15-0.24) µm, whereas the median interpatient fibrin fiber thickness was 0.18 (0.15-0.21) µm. CONCLUSIONS: In this report, we have characterized proteins and fiber fibrin thickness bound to ECMO circuits in six children. The techniques and approaches may be useful for investigating interactions between blood, coagulation, and the ECMO circuit and have the potential for circuit design.

Attitudes and responses of Victorian paediatric intensive care doctors to the detection and reporting of child maltreatment.

AIM: To determine the attitudes and responses of Victorian paediatric intensive care doctors to the detection and reporting of child maltreatment. METHODS: A prospective study conducted in a 30-bed paediatric intensive care unit of a university teaching hospital using data collected from a questionnaire completed by paediatric intensive care consultants and registrars. The questionnaire covered the following domains - doctors' knowledge of Victorian mandatory reporting legislation, doctors' history of reporting and doctors' current role in the detection and reporting of child maltreatment. RESULTS: The questionnaire was completed by 37 doctors. All but one doctor considered their role in the detection and reporting of all six forms of maltreatment (physical abuse, sexual abuse, emotional abuse, neglect, exposure to domestic violence and grooming to facilitate later sexual activity with a child) very important or somewhat important. Thirty-two percent of doctors did not feel adequately trained to detect child maltreatment while 51% did not feel adequately trained to report maltreatment. If a doctor wanted to make a report to Child Protection about the physical or sexual abuse of a child, only one would likely make Child Protection their first point of contact. CONCLUSIONS: Paediatric intensive care doctors show a strong intent to detect and report child maltreatment across a broad range of maltreatment types. Doctors are likely to contact one or more members of a child's care team and/or one or more relevant hospital/community services before making a report to Child Protection about the physical or sexual abuse of a child. Opportunities exist for the further education of doctors in regards to the detection and reporting of child maltreatment.

Why do children not survive extracorporeal membrane oxygenation?

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is used in critically ill children with cardiac and/or respiratory failure. Use is increasing in children with high-risk comorbidities. Reasons children do not survive ECMO are poorly described. AIMS: Describe characteristics and cause of death, compare mortality in children with high-risk comorbidities, evaluate mortality trends over a decade. METHOD: All children <18 years old who received ECMO at this institution from 1 January 2011 to 31 December 2020 were described and categorised by outcome: died on or <48 h post-ECMO, died ≥48 h post-ECMO, survived to hospital discharge. Children who did not survive ECMO (DNSE) were categorised to: ECMO withdrawal for irrecoverable original condition, withdrawal for poor prognosis neurological condition, brain death, withdrawal for poor prognosis with multiple complex conditions, and unsupportable. Poison regression was used to analyse survival trends. RESULTS: Four hundred twenty-eight children received ECMO, 19% DNSE, 14% died ≥48 h post-ECMO and 67% survived. ECMO was electively withdrawn for irrecoverable original condition (39%), poor prognosis for neurological condition (32%) or multiple complex conditions (18%). One hundred twenty-two children had ≥1 high-risk comorbidity. Children with genetic syndromes (58%), risk-adjusted congenital heart surgery score-1 ≥4 (53%), primary immunodeficiency (50%) had lower hospital survival. No children with malignancy/bone marrow transplant survived to hospital discharge. Overall hospital survival was 67%, with no significant change during the study period (P-trend = 0.99). CONCLUSION: Children who DNSE have therapy electively withdrawn for irrecoverable disease or poor prognosis. Children with high-risk comorbidities have a reasonable chance of survival. This study informs clinicians ECMO may be a therapeutic option.

Immunofluorescence Protocol for Characterization of Platelet and Leukocyte Binding in Extracorporeal Membrane Oxygenation (ECMO) Circuits.

The continuous contact between blood and the foreign surface of the extracorporeal membrane oxygenation (ECMO) circuit contributes to hemostatic, inflammatory, and other physiological disturbances observed during ECMO. Although previous studies have extensively investigated blood samples from patients on ECMO, cell adsorption to the ECMO circuit as an additional factor that could potentially influence clinical outcomes, has largely been overlooked. Here we provide a detailed immunofluorescence (IF) protocol designed to characterize cellular binding on ECMO circuits collected from patients. Extracorporeal membrane oxygenation circuits were collected from three pediatric patients and an albumin primed-only ECMO circuit was used as control. Circuit samples from five different sites within each ECMO circuit were collected and processed for the IF protocol. CD14 and CD42a antibodies were used to identify platelets and leukocytes bound to each ECMO circuit sample and images captured using inverted fluorescence microscopy. The protocol enables the comprehensive characterization of platelet and leukocyte binding to ECMO circuits collected from patients, which could in turn extend our knowledge of the characteristics of circuit binding and may provide guidance for improved ECMO circuit design.

Clinical Effects of Nitric Oxide Added to the Oxygenator of Children on Extracorporeal Membrane Oxygenation: Pre-Post Cohort Study.

Nitric oxide (NO) can be safely delivered through the sweep gas to the oxygenator of an extracorporeal membrane oxygenation (ECMO) circuit. It has theoretical benefits such as preventing platelet adhesion to surfaces, mitigating inflammatory response and protection against ischemia-reperfusion injury. In this uncontrolled before-after study of children on ECMO, the outcomes of those who received NO were compared with those who did not. Among 393 ECMO runs (from 337 patients), 192 of 393 (49%) received NO and 201 of 393 (51%) did not. The use of NO was associated with a 37% reduction in circuit change (adjusted risk ratio [aRR]: 0.63, 95% confidence interval [CI]: 0.42-0.93). The aRR (95% CI) for risk of neurologic injury was 0.72 (0.47-1.11). We observed potential heterogeneity of treatment effect for the risk of neurologic injury in children who had cardiac surgery: the risk with NO was lower in those who had cardiac surgery (aRR: 0.50, 95% CI: 0.26-0.96). There was no difference in survival between the study groups. In children managed with NO delivered through the ECMO circuit, we report a reduction in observed rate of circuit change and lower risk of neurologic injury in children who underwent cardiac surgery. Nitric oxide therapy on ECMO warrants prospective evaluation in children.

High risk of necrotising enterocolitis in term-born neonates with CHD delivered by caesarean section: a case-control study.

OBJECTIVE: Necrotising enterocolitis is linked with altered intestinal microbiota, and caesarean birth is associated with imbalance of newborn intestinal microbiome. We aimed to investigate the role of delivery mode (vaginal or caesarean) and gestational age in the development of necrotising enterocolitis among term-born neonates (≥ 37 weeks) with CHD. METHODS: Case-control study. We studied all newborns with CHD who underwent cardiac surgery during the neonatal (≤ 28 days of age) period, between 2007 and 2017. Totally, 60 cases of necrotising enterocolitis were matched (by year of birth and type of congenital heart lesion) with 180 controls (1:3 ratio). Multivariable conditional logistic regression was used to assess the study question. RESULTS: The overall prevalence of necrotising enterocolitis was 6.3% in term-born newborns with CHD. Neonates with a left-ventricular outflow tract lesion or single ventricle lesion accounted for 55% (n = 33) of cases. 62% (n = 37) cases were in the modified Bell's stage 2 or more for necrotising enterocolitis classification. In multivariable modelling, gestational age at birth was not associated with the development of necrotising enterocolitis [adjusted odds ratio per week increase, 95% confidence interval: 1.20 (0.90-1.60)]. Birth by caesarean delivery (compared to vaginal) was strongly associated with development of necrotising enterocolitis [adjusted odds ratio (95% confidence interval): 2.64 (1.31-5.29)]. We failed to identify an association between preoperative enteral nutrition and necrotising enterocolitis. CONCLUSION: This study showed a high risk of necrotising enterocolitis in newborns with critical CHD born via caesarean. This information is important given the high prevalence of planned birth by caesarean in newborns with CHD.

Multi-modal MRI of hippocampal morphometry and connectivity after pediatric severe TBI.

This investigation explores memory performance using the California Verbal Learning Test in relation to morphometric and connectivity measures of the memory network in severe traumatic brain injury. Twenty-two adolescents with severe traumatic brain injury were recruited for multimodal MRI scanning 1-2 years post-injury at 13 participating sites. Analyses included hippocampal volume derived from anatomical T1-weighted imaging, fornix white matter microstructure from diffusion tensor imaging, and hippocampal resting-state functional magnetic resonance imaging connectivity as well as diffusion-based structural connectivity. A typically developing control cohort of forty-nine age-matched children also underwent scanning and neurocognitive assessment. Results showed hippocampus volume was decreased in traumatic brain injury with respect to controls. Further, hippocampal volume loss was associated with worse performance on memory and learning in traumatic brain injury subjects. Similarly, hippocampal fornix fractional anisotropy was reduced in traumatic brain injury with respect to controls, while decreased fractional anisotropy in the hippocampal fornix also was associated with worse performance on memory and learning in traumatic brain injury subjects. Additionally, reduced structural connectivity of left hippocampus to thalamus and calcarine sulcus was associated with memory and learning in traumatic brain injury subjects. Functional connectivity in the left hippocampal network was also associated with memory and learning in traumatic brain injury subjects. These regional findings from a multi-modal neuroimaging approach should not only be useful for gaining valuable insight into traumatic brain injury induced memory and learning disfunction, but may also be informative for monitoring injury progression, recovery, and for developing rehabilitation as well as therapy strategies.

Potential benefits of prenatal diagnosis of TGA in Australia may be outweighed by the adverse effects of earlier delivery: likely causation and potential solutions.

OBJECTIVE: Prenatal diagnosis of transposition of great arteries (TGA) is expected to improve postoperative outcomes after neonatal arterial switch operation (ASO); however, published reports give conflicting results. We aimed to determine the association between prenatal diagnosis and early postoperative outcomes after neonatal ASO. METHODS: Cohort study involving 243 newborns who underwent ASO (70% prenatally diagnosed) between 2010 and 2019. Multivariable regression was used to determine the association between prenatal diagnosis and (a) birth characteristics and (b) postoperative outcomes. RESULTS: Gestational age and birthweight centile were lower and small-for-gestational-age more common (11.8% vs 1.4%) in those diagnosed prenatally. Among births which followed labour induction or prelabour caesarean, prenatal diagnosis was associated with earlier gestation at birth (mean (SD), 38.5 (1.6) vs 39.2 (1.4), p=0.01). Among births which followed spontaneous labour, prenatal diagnosis was associated with earlier gestation at labour onset (38.2 (1.8) vs 39.2 (1.4), p=0.01). Prenatal diagnosis was associated with longer postoperative mechanical ventilation (incidence rate ratio 1.74, 95% CI 1.37 to 2.21), intensive care (1.70, 1.31 to 2.21) and hospital length of stay (1.37, 1.14 to 1.66) after ASO. Gestational age mediated up to 60% of the effect of prenatal diagnosis on postoperative outcomes. CONCLUSION: Among newborns undergoing ASO for TGA, prenatal diagnosis is associated with poorer early postoperative outcomes. In addition to minimising iatrogenic factors (such as planned births) resulting in earlier births, evaluation of other dynamics following a prenatal diagnosis which may result in poor fetal growth and earlier onset of spontaneous labour is important.

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.

A Clinical Score for Quantifying Edema in Mechanically Ventilated Children With Congenital Heart Disease in Intensive Care.

Standardized clinical measurements of edema do not exist. OBJECTIVES: To describe a 19-point clinical edema score (CES), investigate its interobserver agreement, and compare changes between such CES and body weight. DESIGN SETTING AND PARTICIPANTS: Prospective observational study in a tertiary PICU of mechanically ventilated children with congenital heart disease. MAIN OUTCOMES AND MEASURES: Differences in the median CES between observer groups. RESULTS: We studied 61 children, with a median age of 8.0 days (interquartile range, 1.0-14.0 d). A total of 539 CES were performed by three observer groups (medical 1 [reference], medical 2, and bedside nurse) at 0, 24, and 48 hours from enrollment. Overall, there was close agreement between observer groups in mean, median, and upper quartile of CES scores, with least agreement observed in the lower quartile of scores. Across all quartiles of CES, after adjusting for baseline weight, cardiac surgical risk, duration of cardiopulmonary bypass, or peritoneal dialysis during the study, observer groups returned similar mean scores (medical 2: 25th centile +0.1 [95% CI, -0.2 to 0.5], median +0.6 [95% CI, -0.4 to 1.5], 75th centile +0.1 [95% CI, -1.1 to 1.4] and nurse: 25th centile +0.5 [95% CI, 0.0-0.9], median +0.7 [95% CI, 0.0-1.5], 75th centile -0.2 [95% CI, -1.3 to 1.0]) Within a multivariable mixed-effects linear regression model, including adjustment for baseline CES, each 1 point increase in CES was associated with a 12.1 grams (95% CI, 3.2-21 grams) increase in body weight. CONCLUSIONS AND RELEVANCE: In mechanically ventilated children with congenital heart disease, three groups of observers tended to agree when assessing overall edema using an ordinal clinical score assessed in six body regions, with agreement least at low edema scores. An increase in CES was associated with an increase in body weight, suggesting some validity for quantifying edema. Further exploration of the CES as a rapid clinical tool is indicated.

Safety and feasibility of adjunct autologous cord blood stem cell therapy during the Norwood heart operation.

BACKGROUND: We conducted this phase I, open-label safety and feasibility trial of autologous cord blood (CB) stem cell (CBSC) therapy via a novel blood cardioplegia-based intracoronary infusion technique during the Norwood procedure in neonates with an antenatal diagnosis of hypoplastic left heart syndrome (HLHS). CBSC therapy may support early cardiac remodeling with enhancement of right ventricle (RV) function during the critical interstage period. METHODS: Clinical grade CB mononucleated cells (CBMNCs) were processed to NetCord-FACT International Standards. To maximize yield, CBSCs were not isolated from CBMNCs. CBMNCs were stored at 4 °C (no cryopreservation) for use within 3 days and delivered after each cardioplegia dose (4 × 15 mL). RESULTS: Of 16 patients with antenatal diagnosis, 13 were recruited; of these 13 patients, 3 were not treated due to placental abruption (n = 1) or conditions delaying the Norwood for >4 days (n = 2) and 10 received 644.9 ± 134 × 106 CBMNCs, representing 1.5 ± 1.1 × 106 (CD34+) CBSCs. Interstage mortality was 30% (n = 3; on days 7, 25, and 62). None of the 36 serious adverse events (53% linked to 3 deaths) were related to CBMNC therapy. Cardiac magnetic resonance imaging before stage 2 (n = 5) found an RV mass index comparable to that in an exact-matched historical cohort (n = 22), with a mean RV ejection fraction of 66.2 ± 4.5% and mean indexed stroke volume of 47.4 ± 6.2 mL/m2 versus 53.5 ± 11.6% and 37.2 ± 10.3 mL/m2, respectively. All 7 survivors completed stage 2 and are alive with normal RV function (6 with ≤mild and 1 with moderate tricuspid regurgitation). CONCLUSIONS: This trial demonstrated that autologous CBMNCs delivered in large numbers without prior cryopreservation via a novel intracoronary infusion technique at cardioplegic arrest during Norwood palliation on days 2 to 3 of life is feasible and safe.

A qualitative investigation of paediatric intensive care staff attitudes towards the diagnosis of lower respiratory tract infection in the molecular diagnostics era.

Background: In the past decade, molecular diagnostic syndromic arrays incorporating a range of bacterial and viral pathogens have been described. It is unclear how paediatric intensive care unit (PICU) staff diagnose lower respiratory tract infection (LRTI) and integrate diagnostic array results into antimicrobial decision-making. Methods: An online survey with eleven questions was distributed throughout paediatric intensive care societies in the UK, continental Europe and Australasia with a total of 755 members. Participants were asked to rate the clinical factors and investigations they used when prescribing for LRTI. Semi-structured interviews were undertaken with staff who participated in a single-centre observational study of a 52-pathogen diagnostic array. Results: Seventy-two survey responses were received; most responses were from senior doctors. Whilst diagnostic arrays were used less frequently than routine investigations (i.e. microbiological culture), they were of comparable perceived utility when making antimicrobial decisions. Prescribers reported that for arrays to be clinically impactful, they would need to deliver results within 6 h for stable patients and within 1 h for unstable patients to inform their immediate decision to prescribe antimicrobials. From 16 staff interviews, we identified that arrays were helpful for the diagnosis and screening of bacterial LRTI. Staff reported it could be challenging to interpret results in some cases due to the high sensitivity of the test. Therefore, results were considered within the context of the patient and discussed within the multidisciplinary team. Conclusions: Diagnostic arrays were considered of comparable value to microbiological investigations by PICU prescribers. Our findings support the need for further clinical and economic evaluation of diagnostic arrays in a randomised control trial. Trial registration: Clinicaltrials.gov, NCT04233268. Registered on 18 January 2020. Supplementary Information: The online version contains supplementary material available at 10.1007/s44253-023-00008-z.

Agreement Between Measured Weight and Fluid Balance in Mechanically Ventilated Children in Intensive Care.

OBJECTIVES: To investigate the agreement between change in body weight (BW) and fluid balance (FB), and the precision and safety of BW measurement in mechanically ventilated infants in intensive care. DESIGN: Prospective observational study. SETTING: Tertiary PICU. PATIENTS: Infants following cardiac surgery, at baseline, 24 hours, and 48 hours. INTERVENTIONS: BW and FB measurement at three time points. MEASUREMENTS AND MAIN RESULTS: Between May 2021 and September 2022, we studied 61 children. The median age was 8 days (interquartile range [IQR], 1.0-14.0 d). The median BW at baseline was 3,518 g (IQR, 3,134-3,928 g). Change in BW was -36 g (IQR, -145 to 105 g) and -97 g (IQR, -240 to -28 g) between baseline and 24 hours, and between 24 and 48 hours, respectively. Change in FB was -82 mL (IQR, -173 to 12 mL) and -107 mL (IQR, -226 to 103) between baseline and 24 hours, and between 24 and 48 hours, respectively. In Bland-Altman analyses, the mean bias between BW and FB at 24 and 48 hours was 54 g (95% CI, 12-97) and -43 g (95% CI, -108 to 23), respectively. This exceeded 1% of the median BW, and limits of agreement ranged from 7.6% to 15% of baseline BW. The precision of paired weight measurements, performed sequentially at each time interval, was high (median difference of ≤1% of BW at each time point). The median weight of connected devices ranged from 2.7% to 3% of BW. There were no episodes of tube or device dislodgments and no change in vasoactive therapies during weight measurements. CONCLUSIONS: There is moderate agreement between the changes in FB and BW, albeit greater than 1% of baseline BW, and the limits of this agreement are wide. Weighing mechanically ventilated infants in intensive care is a relatively safe and precise method for estimating change in fluid status. Device weight represents a relatively large proportion of BW.

Leadership during airway management in the intensive care unit: A video-reflexive ethnography study.

Effective leadership is crucial to team performance within the intensive care unit. This novel study aimed to explore how staff members from an intensive care unit conceptualize leadership and what facilitators and barriers to leadership exist within a simulated workplace. It also aimed to identify factors that intersect with their perceptions of leadership. This study was underpinned by interpretivism, and video-reflexive ethnography was chosen as the methodology for the study. The use of both video recording (to capture the complex interactions occurring in the ICU) and team reflexivity allowed repeated analysis of those interactions by the research team. Purposive sampling was used to recruit participants from an ICU in a large tertiary and private hospital in Australia. Simulation groups were designed to replicate the typical clinical teams involved in airway management within the intensive care unit. Twenty staff participated in the four simulation activities (five staff per simulation group). Each group simulated the intubations of three patients with hypoxia and respiratory distress due to severe COVID-19. All 20 participants who completed the study simulations were invited to attend video-reflexivity sessions with their respective group. Twelve of the 20 participants (60%) from the simulations took part in the reflexive sessions. Video-reflexivity sessions (142 min) were transcribed verbatim. Transcripts were then imported into NVivo software for analysis. The five stages of framework analysis were used to conduct thematic analysis of the video-reflexivity focus group sessions, including the development of a coding framework. All transcripts were coded in NVivo. NVivo queries were conducted to explore patterns in the coding. The following key themes regarding participants' conceptualizations of leadership within the intensive care were identified: (1) leadership is both a group/shared process and individualistic/hierarchical; (2) leadership is communication; and (3) gender is a key leadership dimension. Key facilitators identified were: (1) role allocation; (2) trust, respect and staff familiarity; and (3) the use of checklists. Key barriers identified were: (1) noise and (2) personal protective equipment. The impact of socio-materiality on leadership within the intensive care unit is also identified.