Timing of Red Blood Cell Transfusions and Occurrence of Necrotizing Enterocolitis: A Secondary Analysis of a Randomized Clinical Trial.

Importance: Observational studies often report that anemia and red blood cell (RBC) transfusions are associated with a higher risk of necrotizing enterocolitis (NEC) among extremely low-birthweight (ELBW) infants. Objective: To evaluate whether there is a temporal association between 72-hour hazard periods of exposure to RBC transfusions and NEC among ELBW infants randomized to either higher or lower hemoglobin transfusion thresholds. Design, Setting, and Participants: This post hoc secondary analysis of 1690 ELBW infants who survived to postnatal day 10 enrolled in the Transfusion of Prematures (TOP) randomized multicenter trial between December 1, 2012, and April 12, 2017, was performed between June 2021 and July 2023. Exposures: First, the distribution of RBC transfusions and the occurrence of NEC up to postnatal day 60 were examined. Second, 72-hour posttransfusion periods were categorized as hazard periods and the pretransfusion periods of variable duration as control periods. Then, the risk of NEC in posttransfusion hazard periods was compared with that in pretransfusion control periods, stratifying the risk based on randomization group (higher or lower hemoglobin transfusion threshold group). Main Outcomes and Measures: The primary outcome was incidence of NEC stage 2 or 3. Secondary outcomes included the incidence rates of NEC within five 10-day intervals, taking into account the number of days at risk. Results: Of 1824 ELBW infants randomized during the TOP trial, 1690 were included in the present analysis (mean [SD] gestational age, 26.0 [1.5] weeks; 899 infants [53.2%] were female). After categorizing 4947 hazard periods and 5813 control periods, we identified 133 NEC cases. Fifty-nine of these cases (44.4%) occurred during hazard periods. Baseline and clinical characteristics of infants with NEC during hazard periods did not differ from those of infants with NEC during control periods. The risk of NEC was 11.9 per 1000 posttransfusion hazard periods and 12.7 per 1000 control periods (adjusted risk ratio, 0.95; 95% CI, 0.68-1.32; P = .74). This risk did not differ significantly between randomization groups, but the incidence rate of NEC per 1000 days peaked between postnatal days 20 and 29 in the lower hemoglobin transfusion threshold group. Conclusions and Relevance: The findings of this post hoc analysis suggest that, among ELBW infants with the hemoglobin ranges occurring in the TOP trial, exposure to RBC transfusions was not temporally associated with a higher risk of NEC during 72-hour posttransfusion hazard periods. Given that the incidence rate of NEC peaked between postnatal days 20 and 29 among infants with lower hemoglobin values, a more in-depth examination of this at-risk period using larger data sets is warranted. Trial Registration: ClinicalTrials.gov Identifier: NCT01702805.

The Diaphragmatic Initiated Ventilatory Assist (DIVA) trial: study protocol for a randomized controlled trial comparing rates of extubation failure in extremely premature infants undergoing extubation to non-invasive neurally adjusted ventilatory assist versus non-synchronized nasal intermittent positive pressure ventilation.

BACKGROUND: Invasive mechanical ventilation contributes to bronchopulmonary dysplasia (BPD), the most common complication of prematurity and the leading respiratory cause of childhood morbidity. Non-invasive ventilation (NIV) may limit invasive ventilation exposure and can be either synchronized or non-synchronized (NS). Pooled data suggest synchronized forms may be superior. Non-invasive neurally adjusted ventilatory assist (NIV-NAVA) delivers NIV synchronized to the neural signal for breathing, which is detected with a specialized catheter. The DIVA (Diaphragmatic Initiated Ventilatory Assist) trial aims to determine in infants born 240/7-276/7 weeks' gestation undergoing extubation whether NIV-NAVA compared to non-synchronized nasal intermittent positive pressure ventilation (NS-NIPPV) reduces the incidence of extubation failure within 5 days of extubation. METHODS: This is a prospective, unblinded, pragmatic, multicenter phase III randomized clinical trial. Inclusion criteria are preterm infants 24-276/7 weeks gestational age who were intubated within the first 7 days of life for at least 12 h and are undergoing extubation in the first 28 postnatal days. All sites will enter an initial run-in phase, where all infants are allocated to NIV-NAVA, and an independent technical committee assesses site performance. Subsequently, all enrolled infants are randomized to NIV-NAVA or NS-NIPPV at extubation. The primary outcome is extubation failure within 5 days of extubation, defined as any of the following: (1) rise in FiO2 at least 20% from pre-extubation for > 2 h, (2) pH ≤ 7.20 or pCO2 ≥ 70 mmHg; (3) > 1 apnea requiring positive pressure ventilation (PPV) or ≥ 6 apneas requiring stimulation within 6 h; (4) emergent intubation for cardiovascular instability or surgery. Our sample size of 478 provides 90% power to detect a 15% absolute reduction in the primary outcome. Enrolled infants will be followed for safety and secondary outcomes through 36 weeks' postmenstrual age, discharge, death, or transfer. DISCUSSION: The DIVA trial is the first large multicenter trial designed to assess the impact of NIV-NAVA on relevant clinical outcomes for preterm infants. The DIVA trial design incorporates input from clinical NAVA experts and includes innovative features, such as a run-in phase, to ensure consistent technical performance across sites. TRIAL REGISTRATION: www. CLINICALTRIALS: gov , trial identifier NCT05446272 , registered July 6, 2022.

Randomized Controlled Trials of Pulmonary Vasodilator Therapy Adjunctive to Inhaled Nitric Oxide for Persistent Pulmonary Hypertension of the Newborn: A Systematic Review.

Inhaled nitric oxide (iNO) is a pulmonary vasodilator considered standard of care to treat persistent pulmonary hypertension of the newborn. However, not all infants respond to iNO. The authors performed a systematic review to examine methodology, outcomes, and challenges of randomized controlled trials testing pulmonary vasodilator medications adjunctive to iNO. The 5 trials identified showed heterogeneity in eligibility criteria and outcomes assessed. No trial achieved recruitment goals, limiting conclusions regarding efficacy, safety, and pharmacology. Trial design consensus and alternative methodologic strategies such as deferred consent, real-world controls, nonrandomized database assessments, and Bayesian statistical approaches are needed.

Missing Outcome Data in Recent Perinatal and Neonatal Clinical Trials.

Missing outcome data in clinical trials may jeopardize the validity of the trial results and inferences for clinical practice. Although sick and preterm newborns are treated as a captive patient population during their stay in the NICUs, their long-term outcomes are often ascertained after discharge. This greatly increases the risk of attrition. We surveyed recently published perinatal and neonatal randomized trials in 7 high-impact general medical and pediatric journals to review the handling of missing primary outcome data and any choice of imputation methods. Of 87 eligible trials in this survey, 77 (89%) had incomplete primary outcome data. The missing outcome data were not discussed at all in 9 reports (12%). Most study teams restricted their main analysis to participants with complete information for the primary outcome (61 trials; 79%). Only 38 of the 77 teams (49%) performed sensitivity analyses using a variety of imputation methods. We conclude that the handling of missing primary outcome data was frequently inadequate in recent randomized perinatal and neonatal trials. To improve future approaches to missing outcome data, we discuss the strengths and limitations of different imputation methods, the appropriate estimation of sample size, and how to deal with data withdrawal. However, the best strategy to reduce bias from missing outcome data in perinatal and neonatal trials remains prevention. Investigators should anticipate and preempt missing data through careful study design, and closely monitor all incoming primary outcome data for completeness during the conduct of the trial.

Overnight staffing in Canadian neonatal and pediatric intensive care units.

Aim: Infants and children who require specialized medical attention are admitted to neonatal and pediatric intensive care units (ICUs) for continuous and closely supervised care. Overnight in-house physician coverage is frequently considered the ideal staffing model. It remains unclear how often this is achieved in both pediatric and neonatal ICUs in Canada. The aim of this study is to describe overnight in-house physician staffing in Canadian pediatric and level-3 neonatal ICUs (NICUs) in the pre-COVID-19 era. Methods: A national cross-sectional survey was conducted in 34 NICUs and 19 pediatric ICUs (PICUs). ICU directors or their delegates completed a 29-question survey describing overnight staffing by resident physicians, fellow physicians, nurse practitioners, and attending physicians. A comparative analysis was conducted between ICUs with and without in-house physicians. Results: We obtained responses from all 34 NICUs and 19 PICUs included in this study. A total of 44 ICUs (83%) with in-house overnight physician coverage provided advanced technologies, such as extracorporeal life support, and included all ICUs that catered to patients with cardiac, transplant, or trauma conditions. Residents provided the majority of overnight coverage, followed by the Critical Care Medicine fellows. An attending physician was in-house overnight in eight (15%) out of the 53 ICUs, seven of which were NICUs. Residents participating in rotations in the ICU would often have rotation durations of less than 6 weeks and were often responsible for providing care during shifts lasting 20-24 h. Conclusion: Most PICUs and level-3 NICUs in Canada have a dedicated in-house physician overnight. These physicians are mainly residents or fellows, but a notable variation exists in this arrangement. The potential effects on patient outcomes, resident learning, and physician satisfaction remain unclear and warrant further investigation.

Thresholds for Red Blood Cell Transfusion in Preterm Infants: Evidence to Practice.

Rapid blood loss with circulatory shock is dangerous for the preterm infant as cardiac output and oxygen-carrying capacity are simultaneously imperilled. This requires prompt restoration of circulating blood volume with emergency transfusion. It is recommended that clinicians use both clinical and laboratory responses to guide transfusion requirements in this situation. For preterm infants with anemia of prematurity, it is recommended that clinicians use a restrictive algorithm from one of two recently published clinical trials. Transfusion outside these algorithms in very preterm infants is not evidence-based and is actively discouraged.

Tissue Oxygenation Changes After Transfusion and Outcomes in Preterm Infants: A Secondary Near-Infrared Spectroscopy Study of the Transfusion of Prematures Randomized Clinical Trial (TOP NIRS).

Importance: Preterm infants with varying degrees of anemia have different tissue oxygen saturation responses to red blood cell (RBC) transfusion, and low cerebral saturation may be associated with adverse outcomes. Objective: To determine whether RBC transfusion in preterm infants is associated with increases in cerebral and mesenteric tissue saturation (Csat and Msat, respectively) or decreases in cerebral and mesenteric fractional tissue oxygen extraction (cFTOE and mFTOE, respectively) and whether associations vary based on degree of anemia, and to investigate the association of Csat with death or neurodevelopmental impairment (NDI) at 22 to 26 months corrected age. Design, Setting, and Participants: This was a prospective observational secondary study conducted among a subset of infants between August 2015 and April 2017 in the Transfusion of Prematures (TOP) multicenter randomized clinical trial at 16 neonatal intensive care units of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Preterm neonates with gestational age 22 to 28 weeks and birth weight 1000 g or less were randomized to higher or lower hemoglobin thresholds for transfusion. Data were analyzed between October 2020 and May 2022. Interventions: Near-infrared spectroscopy monitoring of Csat and Msat. Main Outcomes and Measures: Primary outcomes were changes in Csat, Msat, cFTOE, and mFTOE after transfusion between hemoglobin threshold groups, adjusting for age at transfusion, gestational age, birth weight stratum, and center. Secondary outcome at 22 to 26 months was death or NDI defined as cognitive delay (Bayley Scales of Infant and Toddler Development-III score <85), cerebral palsy with Gross Motor Function Classification System level II or greater, or severe vision or hearing impairment. Results: A total of 179 infants (45 [44.6%] male) with mean (SD) gestational age 25.9 (1.5) weeks were enrolled, and valid data were captured from 101 infants during 237 transfusion events. Transfusion was associated with a significant increase in mean Csat of 4.8% (95% CI, 2.7%-6.9%) in the lower-hemoglobin threshold group compared to 2.7% (95% CI, 1.2%-4.2%) in the higher-hemoglobin threshold group, while mean Msat increased 6.7% (95% CI, 2.4%-11.0%) vs 5.6% (95% CI, 2.7%-8.5%). Mean cFTOE and mFTOE decreased in both groups to a similar extent. There was no significant change in peripheral oxygen saturation (SpO2) in either group (0.2% vs -0.2%). NDI or death occurred in 36 infants (37%). Number of transfusions with mean pretransfusion Csat less than 50% was associated with NDI or death (odds ratio, 2.41; 95% CI, 1.08-5.41; P = .03). Conclusions and Relevance: In this secondary study of the TOP randomized clinical trial, Csat and Msat were increased after transfusion despite no change in SpO2. Lower pretransfusion Csat may be associated with adverse outcomes, supporting further investigation of targeted tissue saturation monitoring in preterm infants with anemia. Trial Registration: ClinicalTrials.gov Identifier: NCT01702805.

Echocardiographic Assessment of Pulmonary Arterial Hypertension Following Inhaled Nitric Oxide in Infants with Severe Bronchopulmonary Dysplasia.

OBJECTIVES: Inhaled nitric oxide (iNO) is an effective pulmonary vasodilator. However, the efficacy of iNO in former premature infants with established bronchopulmonary dysplasia (BPD) has not been studied. This study aimed to determine the efficacy of iNO in reducing pulmonary artery pressure in infants with severe BPD as measured by echocardiography. STUDY DESIGN: Prospective, observational study enrolling infants born at less than 32 weeks gestation and in whom (1) iNO therapy was initiated after admission to our institution, or (2) at the outside institution less than 48 h before transfer and received an echocardiogram prior to iNO initiation, and (3) had severe BPD. Data were collected at three time-points: (1) before iNO; (2) 12-48 h after initiation of iNO; and (3) 48-168 h after initiation of iNO. The primary outcome was the effect of iNO on pulmonary artery pressure measured by echocardiography in patients with severe BPD between 48 and 168 h after initiating iNO therapy. RESULTS: Of 37 enrolled, 81% had echocardiographic evidence of pulmonary arterial hypertension (PAH) before iNO and 56% after 48 h of iNO (p = 0.04). FiO2 requirements were significantly different between time-points (1) and (3) (p = 0.05). There were no significant differences between Tricuspid Annular Plane Systolic Excursion (TAPSE) Z-Scores, time to peak velocity: right ventricular ejection time (TPV:RVET), and ventilator changes. CONCLUSIONS: Although we found a statistically significant reduction of PAH between time-point (1) and (3), future trials are needed to further guide clinical care.

Nasal intermittent positive pressure ventilation (NIPPV) versus nasal continuous positive airway pressure (NCPAP) for preterm neonates after extubation.

BACKGROUND: Nasal continuous positive airway pressure (NCPAP) is a useful method for providing respiratory support after extubation. Nasal intermittent positive pressure ventilation (NIPPV) can augment NCPAP by delivering ventilator breaths via nasal prongs. OBJECTIVES: Primary objective To determine the effects of management with NIPPV versus NCPAP on the need for additional ventilatory support in preterm infants whose endotracheal tube was removed after a period of intermittent positive pressure ventilation. Secondary objectives To compare rates of abdominal distension, gastrointestinal perforation, necrotising enterocolitis, chronic lung disease, pulmonary air leak, mortality, duration of hospitalisation, rates of apnoea and neurodevelopmental status at 18 to 24 months for NIPPV and NCPAP. To compare the effect of NIPPV versus NCPAP delivered via ventilators versus bilevel devices, and assess the effects of the synchronisation of ventilation, and the strength of interventions in different economic settings. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was January 2023. SELECTION CRITERIA: We included randomised and quasi-randomised trials of ventilated preterm infants (less than 37 weeks' gestational age (GA)) ready for extubation to non-invasive respiratory support. Interventions were NIPPV and NCPAP. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcome was 1. respiratory failure. Our secondary outcomes were 2. endotracheal reintubation, 3. abdominal distension, 4. gastrointestinal perforation, 5. necrotising enterocolitis (NEC), 6. chronic lung disease, 7. pulmonary air leak, 8. mortality, 9. hospitalisation, 10. apnoea and bradycardia, and 11. neurodevelopmental status. We used GRADE to assess the certainty of evidence. MAIN RESULTS: We included 19 trials (2738 infants). Compared to NCPAP, NIPPV likely reduces the risk of respiratory failure postextubation (risk ratio (RR) 0.75, 95% confidence interval (CI) 0.67 to 0.84; number needed to treat for an additional beneficial outcome (NNTB) 11, 95% CI 8 to 17; 19 trials, 2738 infants; moderate-certainty evidence) and endotracheal reintubation (RR 0.78, 95% CI 0.70 to 0.87; NNTB 12, 95% CI 9 to 25; 17 trials, 2608 infants, moderate-certainty evidence), and may reduce pulmonary air leaks (RR 0.57, 95% CI 0.37 to 0.87; NNTB 50, 95% CI 33 to infinite; 13 trials, 2404 infants; low-certainty evidence). NIPPV likely results in little to no difference in gastrointestinal perforation (RR 0.89, 95% CI 0.58 to 1.38; 8 trials, 1478 infants, low-certainty evidence), NEC (RR 0.86, 95% CI 0.65 to 1.15; 10 trials, 2069 infants; moderate-certainty evidence), chronic lung disease defined as oxygen requirement at 36 weeks (RR 0.93, 95% CI 0.84 to 1.05; 9 trials, 2001 infants; moderate-certainty evidence) and mortality prior to discharge (RR 0.81, 95% CI 0.61 to 1.07; 11 trials, 2258 infants; low-certainty evidence). When considering subgroup analysis, ventilator-generated NIPPV likely reduces respiratory failure postextubation (RR 0.49, 95% CI 0.40 to 0.62; 1057 infants; I2 = 47%; moderate-certainty evidence), while bilevel devices (RR 0.95, 95% CI 0.77 to 1.17; 716 infants) or a mix of both ventilator-generated and bilevel devices likely results in little to no difference (RR 0.87, 95% CI 0.73 to 1.02; 965 infants). AUTHORS' CONCLUSIONS: NIPPV likely reduces the incidence of extubation failure and the need for reintubation within 48 hours to one-week postextubation more effectively than NCPAP in very preterm infants (GA 28 weeks and above). There is a paucity of data for infants less than 28 weeks' gestation. Pulmonary air leaks were also potentially reduced in the NIPPV group. However, it has no effect on other clinically relevant outcomes such as gastrointestinal perforation, NEC, chronic lung disease or mortality. Ventilator-generated NIPPV appears superior to bilevel devices in reducing the incidence of respiratory failure postextubation failure and need for reintubation. Synchronisation used to deliver NIPPV may be important; however, data are insufficient to support strong conclusions. Future trials should enrol a sufficient number of infants, particularly those less than 28 weeks' GA, to detect differences in death or chronic lung disease and should compare different categories of devices, establish the impact of synchronisation of NIPPV on safety and efficacy of the technique as well as the best combination of settings for NIPPV (rate, peak pressure and positive end-expiratory). Trials should strive to match the mean airway pressure between the intervention groups to allow a better comparison. Neurally adjusted ventilatory assist needs further assessment with properly powered randomised trials.

Early nasal intermittent positive pressure ventilation (NIPPV) versus early nasal continuous positive airway pressure (NCPAP) for preterm infants.

BACKGROUND: Nasal continuous positive airway pressure (NCPAP) is a strategy to maintain positive airway pressure throughout the respiratory cycle through the application of a bias flow of respiratory gas to an apparatus attached to the nose. Early treatment with NCPAP is associated with decreased risk of mechanical ventilation exposure and might reduce chronic lung disease. Nasal intermittent positive pressure ventilation (NIPPV) is a form of noninvasive ventilation delivered through the same nasal interface during which patients are exposed to short inflations, along with background end-expiratory pressure. OBJECTIVES: To examine the risks and benefits of early (within the first six hours after birth) NIPPV versus early NCPAP for preterm infants at risk of or with respiratory distress syndrome (RDS). Primary endpoints are respiratory failure and the need for intubated ventilatory support during the first week of life. Secondary endpoints include the incidence of mortality, chronic lung disease (CLD) (oxygen therapy at 36 weeks' postmenstrual age), pneumothorax, duration of respiratory support, duration of oxygen therapy, and intraventricular hemorrhage (IVH). SEARCH METHODS: Searches were conducted in January 2023 in CENTRAL, MEDLINE, Embase, Web of Science, and Dissertation Abstracts. The reference lists of related systematic reviews and of studies selected for inclusion were also searched. SELECTION CRITERIA: We considered all randomized and quasi-randomized controlled trials. Eligible studies compared NIPPV versus NCPAP treatment, starting within six hours after birth in preterm infants (< 37 weeks' gestational age (GA)). DATA COLLECTION AND ANALYSIS: We collected and analyzed data using the recommendations of the Cochrane Neonatal Review Group. MAIN RESULTS: We included 17 trials, enrolling 1958 infants in this review. NIPPV likely reduces the rate of respiratory failure (risk ratio (RR) 0.65, 95% confidence interval (CI) 0.54 to 0.78; risk difference (RD) -0.08, 95% CI -0.12 to -0.05; 17 RCTs, 1958 infants; moderate-certainty evidence) and needing endotracheal tube ventilation (RR 0.67, 95% CI 0.56 to 0.81; RD -0.07, 95% CI -0.11 to -0.04; 16 RCTs; 1848 infants; moderate-certainty evidence) amongst infants treated with early NIPPV compared with early NCPAP. The meta-analysis demonstrated that NIPPV may reduce the risk of developing CLD compared to CPAP (RR 0.70, 95% CI 0.52 to 0.92; 12 RCTs, 1284 infants; low-certainty evidence) slightly. NIPPV may result in little to no difference in mortality (RR 0.82, 95% CI 0.62 to 1.10; 17 RCTs; 1958 infants; I2 of 0%; low-certainty evidence), the incidence of pneumothorax (RR 0.92, 95% CI 0.60 to 1.41; 16 RCTs; 1674 infants; I2 of 0%; low-certainty evidence), and rates of severe IVH (RR 0.98, 95% CI 0.53 to 1.79; 8 RCTs; 977 infants; I2 of 0%; low-certainty evidence). AUTHORS' CONCLUSIONS: When applied within six hours after birth, NIPPV likely reduces the risk of respiratory failure and the need for intubation and endotracheal tube ventilation in very preterm infants (GA 28 weeks and above) with respiratory distress syndrome or at risk for RDS. It may also decrease the rate of CLD slightly. However, most trials enrolled infants with a gestational age of approximately 28 to 32 weeks with an overall mean gestational age of around 30 weeks. As such, the results of this review may not apply to extremely preterm infants that are most at risk of needing mechanical ventilation or developing CLD. Additional studies are needed to confirm these results and to assess the safety of NIPPV compared with NCPAP alone in a larger patient population.

Searching for evidence in neonatology.

Evidence-based medicine has changed clinical practice by incorporating data from randomised controlled trials (RCTs). While some biases in RCTs are well recognised, we discuss some less acknowledged. Selection bias may arise in the consent stage. Industry-funded studies more often report a positive outcome. Post-hoc changes of outcome measures and other mis-reporting lowers the reliability of outcome data. Finally, even the GRADE system retains subjectivity. CONCLUSION: Moving from "intuition" into "evidence-based" medicine involves grappling with several pitfalls. These pose challenges for authors, editors, reviewers, and readers. All require vigilance before drawing conclusions from presented data.

Lung biopsy in infants with severe bronchopulmonary dysplasia.

INTRODUCTION: Lung biopsy is infrequently performed in the population of infants with severe bronchopulmonary dysplasia (BPD). Yet, its presentation may overlap with other infant diffuse lung diseases, including those within the spectrum of childhood interstitial lung diseases (chILD). Lung biopsy might differentiate between these entities or identify those with an extremely poor prognosis. Both might alter the clinical management of some infants diagnosed with BPD. METHODS: In this tertiary referral center, we drew on a retrospective cohort of 308 preterm infants with severe BPD. Of these, nine underwent lung biopsy between 2012 and 2017. We aimed to assess the indication for lung biopsy, the prior clinical history, safety of the procedure, and describe the biopsy findings. Finally, we considered management decisions in relation to the biopsy results in these patients. RESULTS: All nine infants undergoing biopsy survived the procedure. The mean gestational age and birth weight of the nine patients were 30 ± 3 (range 27-34) weeks and 1421 ± 571 (range 611-2140) grams. All infants received serial echocardiograms to assess pulmonary hypertension, genetic testing, and computed tomography angiography (CTA) before biopsy. In all nine patients moderate to severe alveolar simplification was present and eight had some degree of pulmonary interstitial glycogenosis (PIG) ranging from focal to diffuse. Following biopsy, two infants with PIG received high dose systemic steroids and two separate infants had care redirected. CONCLUSION: In our cohort, lung biopsy was safe and well tolerated. Findings from lung biopsy may aid decision making in selected patients as a part of a step-wise diagnostic algorithm.

High continuous positive airway pressures versus non-invasive positive pressure ventilation in preterm neonates: protocol for a multicentre pilot randomised controlled trial.

INTRODUCTION: Low pressure nasal continuous positive airway pressure (nCPAP) has long been the mainstay of non-invasive respiratory support for preterm neonates, at a constant distending pressure of 5-8 cmH2O. When traditional nCPAP pressures are insufficient, other modes including nasal intermittent positive pressure ventilation (NIPPV) are used. In recent years, high nCPAP pressures (≥9 cmH2O) have also emerged as an alternative. However, the comparative benefits and risks of these modalities remain unknown. METHODS AND ANALYSIS: In this multicentre pilot randomised controlled trial, infants <29 weeks' gestational age (GA) who either: (A) fail treatment with traditional nCPAP or (B) being extubated from invasive mechanical ventilation with mean airway pressure ≥10 cmH2O, will be randomised to receive either high nCPAP (positive end-expiratory pressure 9-15 cmH2O) or NIPPV (target mean Paw 9-15 cmH2O). Primary outcome is feasibility of the conduct of a larger, definitive trial as assessed by rates of recruitment and protocol violations. The main secondary outcome is failure of assigned treatment within 7 days postrandomisation. Multiple other clinical outcomes including bronchopulmonary dysplasia will be ascertained. All randomised participants will be analysed using intention to treat. Baseline and demographic variables as well as outcomes will be summarised and compared using univariate analyses, and a p<0.05 will be considered significant. ETHICS AND DISSEMINATION: The trial has been approved by the respective research ethics boards at each institution (McMaster Children's Hospital: Hamilton integrated REB approval #2113; Royal Alexandra Hospital: Health Research Ethics Board approval ID Pro00090244; Westmead Hospital: Human Research Ethics Committee approval ID 2022/ETH01343). Written, informed consent will be obtained from all parents/guardians prior to study enrolment. The findings of this pilot study will be disseminated via presentations at national and international conferences and via publication in a peer-reviewed journal. Social media platforms including Twitter will also be used to generate awareness. TRIAL REGISTRATION NUMBER: NCT03512158.

Change in neurodevelopmental outcomes for extremely premature infants over time: a systematic review and meta-analysis.

OBJECTIVE: Survival rates of extremely premature infants are rising, but changes in neurodevelopmental impairment (NDI) rates are unclear. Our objective was to perform a systematic review of intrainstitutional variability of NDI over time. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Ovid MEDLINE, Embase, PubMed, Cochrane Library and Google Scholar. STUDY SELECTION: Study eligibility: (1) at least two discrete cohorts of infants born <27 weeks' gestation or <1000 g birth weight, (2) one cohort born after 1990 and at least one subsequent cohort of similar gestational age, (3) all cohorts cared for within the same Neonatal Intensive Care Unit(s) (NICU) and (4) neurodevelopmental outcomes at 18-36 months corrected age. MAIN OUTCOME: Change in NDI rates. Quality, validity and bias were assessed using Grading of Recommendations, Assessment, Development, and Evaluation and Quality in Prognosis Studies guidelines. RESULTS: Of 203 publications, 15 were eligible, including 13 229 infants. At the first time point, average NDI rate across study groups weighted by sample size was 41.0% (95% CI 34.0% to 48.0%). The average change in NDI between time points was -3.3% (95% CI -8·8% to 2.2%). For each added week of gestation at birth, the rate of NDI declined by 9.7% (95% CI 6.2% to 13.3%). Most studies exhibited moderate-severe bias in at least one domain, especially attrition rates. CONCLUSIONS: When comparing discrete same-centre cohorts over time, there was no significant change in NDI rates in infants born <27 weeks' gestation or <1000 g. Higher survival rates unaccompanied by improvement in neurodevelopment highlight urgency for renewed focus on the causes of NDI and evidence-based strategies to reduce brain injury.

Use of ventilation/perfusion mismatch to guide individualised CPAP level selection in preterm infants: a feasibility trial.

OBJECTIVE: To measure within-subject changes in ventilation/perfusion (V'/Q') mismatch in response to a protocol of individualised nasal continuous positive airway pressure (CPAP) level selection. DESIGN: Single-arm, non-randomised, feasibility trial. SETTING: Three centres in the Children's Hospital of Philadelphia neonatal care network. PATIENTS: Twelve preterm infants of postmenstrual age 27-35 weeks, postnatal age >24 hours, and receiving a fraction of inspired oxygen (FiO2) >0.25 on CPAP of 4-7 cm H2O. INTERVENTIONS: We applied a protocol of stepwise CPAP level changes, with the overall direction and magnitude guided by individual responses in V'/Q' mismatch, as determined by the degree of right shift (kilopascals, kPa) in a non-invasive gas exchange model. Best CPAP level was defined as the final pressure level at which V'/Q' improved by more than 5%. MAIN OUTCOME MEASURES: Within-subject change in V'/Q' mismatch between baseline and best CPAP levels. RESULTS: There was a median (IQR) within-subject reduction in V'/Q' mismatch of 1.2 (0-3.2) kPa between baseline and best CPAP levels, p=0.02. Best CPAP was observed at a median (range) absolute level of 7 (5-8) cm H2O. CONCLUSIONS: Non-invasive measures of V'/Q' mismatch may be a useful approach for identifying individualised CPAP levels in preterm infants. The results of our feasibility study should be interpreted cautiously and replication in larger studies evaluating the impact of this approach on clinical outcomes is needed. TRIAL REGISTRATION NUMBER: NCT02983825.

Standardized Outcome Measures for Preterm and Hospitalized Neonates: An ICHOM Standard Set.

INTRODUCTION: Approximately, one in ten infants is born preterm or requires hospitalization at birth. These complications at birth have long-term consequences that can extend into childhood and adulthood. Timely detection of developmental delay through surveillance could enable tailored support for these babies and their families. However, the possibilities for follow-up are limited, especially in middle- and low-income countries, and the tools to do so are either not available or too expensive. A standardized and core set of outcomes for neonates, with feasible tools for evaluation and follow-up, could result in improving quality, enhance shared decision-making, and enable global benchmarking. METHODS: The International Consortium for Health Outcomes Measurement (ICHOM) convened an international working group, which was comprised of 14 health-care professionals (HCP) and 6 patient representatives in the field of neonatal care. An outcome set was developed using a three-round modified Delphi process, and it was endorsed through a patient representative-validation survey and an HCP survey. RESULTS: A literature review revealed 1,076 articles and 26 registries which were screened for meaningful outcomes, patient-reported outcome measures, clinical measures, and case mix variables. This resulted in a neonatal set with 21 core outcomes covering three domains (physical, social, and mental functioning) and 14 tools to assess these outcomes at three timepoints. DISCUSSION: This set can be implemented globally and it will allow comparison of outcomes across different settings and countries. The transparent consensus-driven development process which involved stakeholders and professionals from all over the world ensures global relevance.

Early brain and abdominal oxygenation in extremely low birth weight infants.

BACKGROUND: Extremely low birth weight (ELBW) infants are at risk for end-organ hypoxia and ischemia. Regional tissue oxygenation of the brain and gut as monitored with near-infrared spectroscopy (NIRS) may change with postnatal age, but normal ranges are not well defined. METHODS: A prospective study of ELBW preterm infants utilized NIRS monitoring to assess changes in cerebral and mesenteric saturation (Csat and Msat) over the first week after birth. This secondary study of a multicenter trial comparing hemoglobin transfusion thresholds assessed cerebral and mesenteric fractional tissue oxygen extraction (cFTOE and mFTOE) and relationships with perinatal variables. RESULTS: In 124 infants, both Csat and Msat declined over the first week, with a corresponding increase in oxygen extraction. With lower gestational age, lower birth weight, and 5-min Apgar score ≤5, there was a greater increase in oxygen extraction in the brain compared to the gut. Infants managed with a lower hemoglobin transfusion threshold receiving ≥2 transfusions in the first week had the lowest Csat and highest cFTOE (p < 0.001). CONCLUSION: Brain oxygen extraction preferentially increased in more immature and anemic preterm infants. NIRS monitoring may enhance understanding of cerebral and mesenteric oxygenation patterns and inform future protective strategies in the preterm ELBW population. IMPACT: Simultaneous monitoring of cerebral and mesenteric tissue saturation demonstrates the balance of oxygenation between preterm brain and gut and may inform protective strategies. Over the first week, oxygen saturation of the brain and gut declines as oxygen extraction increases. A low hemoglobin transfusion threshold is associated with lower cerebral saturation and higher cerebral oxygen extraction compared to a high hemoglobin transfusion threshold, although this did not translate into clinically relevant differences in the TOP trial primary outcome. Greater oxygen extraction by the brain compared to the gut occurs with lower gestational age, lower birth weight, and 5-min Apgar score ≤5.