Nasal High-Flow Therapy for Primary Respiratory Support in Preterm Infants

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.

Comparison of the effectiveness of different high-flow devices in neonatal care

OBJECTIVE

To evaluate the success rate of high-flow nasal cannula (HFNC) therapy using an adapted obsolete mechanical ventilator (MV), Optiflow™ and Vapotherm™ in newborns (NBs).

METHOD

This was a retrospective observational study conducted in the neonatal intensive care unit (NICU). The sample comprised NBs who underwent HFNC therapy due to ventilatory dysfunction, for weaning from non-invasive ventilation (NIV), or post-extubation. The three groups, stratified according to gestational age (GA) and birth weight, and corrected GA and weight at the beginning of HFNC use, were as follows: Optiflow ™, Vapotherm ™, and obsolete Mechanical Ventilator (MV) adapted for high flow therapy. Subsequently, the NBs were divided into a success group (SG) and a failure group (FG). HFNC success was defined as a therapy duration exceeding 72 h.

RESULTS

A total of 209 NBs were evaluated, with 31.1 % using HFNC due to ventilatory dysfunction, 2.4 % after extubation, and 66.5 % after NIV weaning. HFNC success rate was observed in 90.9 % of the NBs, with no difference between equipment types (Vapotherm ™, Optiflow ™, and adapted VM).

CONCLUSION

Different types of HFNC equipment are equally effective when used in neonatology for respiratory dysfunction, as a method of weaning from NIV and post-extubation. Adapted obsolete MV can be an alternative for HFCN therapy in resource-constrained settings.

Noninvasive Ventilation

Systematic Reviews and Randomized clinical trials have shown that the use of noninvasive ventilation (NIV) compared to invasive mechanical ventilation reduces the risk of bronchopulmonary dysplasia and or mortality. Most commonly used NIV modes include nasal continuous positive airway pressure, bi-phasic modes, such as, bi-level positive airway pressure, nasal intermittent positive pressure ventilation, high flow nasal cannula, noninvasive neurally adjusted ventilatory assist, and nasal high frequency ventilation are discussed in this review.

High Flow Nasal Cannula for Weaning Nasal Continuous Positive Airway Pressure in Preterm Infants: A Systematic Review and Meta-Analysis

INTRODUCTION

The aim of this study was to systematically review the benefits and harms of using a high-flow nasal cannula (HFNC) for weaning continuous positive airway pressure (CPAP) support in preterm infants.

METHODS

Cochrane Central, EMBASE, Medline, and Web of Science were searched from inception to July 15, 2023. Randomised clinical trials (RCTs) comparing weaning CPAP using HFNC versus weaning CPAP alone and evaluating predefined outcomes were included. Two authors independently performed data extraction and methodological quality assessment. Meta-analysis was conducted using a random-effects model, and the certainty of evidence was assessed using Cochrane GRADE.

RESULTS

Among 843 identified records, seven RCTs involving 781 preterm infants were eligible for analysis. The meta-analysis found no statistically significant difference in duration of respiratory support when using HFNC for weaning compared to weaning CPAP alone (mean difference (95% confidence interval) 3.52 (-0.02, 7.05); 5 RCTs; participants = 488; I2 = 29%). The evidence certainty was downgraded to low due to study limitations and imprecision. There were no significant differences in secondary outcomes, except for a lower occurrence of nasal trauma with HFNC for weaning CPAP compared to weaning CPAP alone (relative risk (95% confidence interval) 0.61 (0.38, 0.99); 4 RCTs; participants = 335; I2 = 0%). The evidence certainty for the secondary outcomes was low to very low.

CONCLUSION

Low certainty of evidence suggests using HFNC for weaning CPAP in preterm infants may not impact the duration of respiratory support. Caution is advised when considering HFNC for weaning CPAP, especially in extremely preterm infants, until additional supportive evidence on its safety becomes available.

High-flow nasal cannula oxygen versus noninvasive ventilation for the management of acute cardiogenic pulmonary edema: a randomized controlled pilot study

BACKGROUND

Whether high-flow nasal oxygen can improve clinical signs of acute respiratory failure in acute heart failure (AHF) is uncertain.

OBJECTIVE

To compare the effect of high-flow oxygen with noninvasive ventilation (NIV) on respiratory rate in patients admitted to an emergency department (ED) for AHF-related acute respiratory failure.

DESIGN, SETTINGS AND PARTICIPANTS

Multicenter, randomized pilot study in three French EDs. Adult patients with acute respiratory failure due to suspected AHF were included. Key exclusion criteria were urgent need for intubation, Glasgow Coma Scale <13 points or hemodynamic instability.

INTERVENTION

Patients were randomly assigned to receive high-flow oxygen (minimum 50 l/min) or noninvasive bilevel positive pressure ventilation.

OUTCOMES MEASURE

The primary outcome was change in respiratory rate within the first hour of treatment and was analyzed with a linear mixed model. Secondary outcomes included changes in pulse oximetry, heart rate, blood pressure, blood gas samples, comfort, treatment failure and mortality.

MAIN RESULTS

Among the 145 eligible patients in the three participating centers, 60 patients were included in the analysis [median age 86 (interquartile range (IQR), 90; 92) years]. There was a median respiratory rate of 30.5 (IQR, 28; 33) and 29.5 (IQR, 27; 35) breaths/min in the high-flow oxygen and NIV groups respectively, with a median change of -10 (IQR, -12; -8) with high-flow nasal oxygen and -7 (IQR, -11; -5) breaths/min with NIV [estimated difference -2.6 breaths/min (95% confidence interval (CI), -0.5-5.7), P = 0.052] at 60 min. There was a median SpO2 of 95 (IQR, 92; 97) and 96 (IQR, 93; 97) in the high-flow oxygen and NIV groups respectively, with a median change at 60 min of 2 (IQR, 0; 5) with high-flow nasal oxygen and 2 (IQR, -1; 5) % with NIV [estimated difference 0.8% (95% CI, -1.1-2.8), P = 0.60]. PaO2, PaCO2 and pH did not differ at 1 h between groups, nor did treatment failure, intubation and mortality rates.

CONCLUSION

In this pilot study, we did not observe a statistically significant difference in changes in respiratory rate among patients with acute respiratory failure due to AHF and managed with high-flow oxygen or NIV. However, the point estimate and its large confidence interval may suggest a benefit of high-flow oxygen.

TRIAL REGISTRATION

NCT04971213 (https://clinicaltrials.gov).

Heated and humidified high flow therapy (HHHFT) in extreme and very preterm neonates with respiratory distress syndrome (RDS): a retrospective cohort from a tertiary care setting in Pakistan

OBJECTIVE

To determine the role of heated humidified high flow therapy (HHHFT) as primary respiratory support in spontaneously breathing moderate-late, very and extreme preterm neonates with respiratory distress syndrome (RDS) at a tertiary care hospital from a developing country.

DESIGN

Retrospective cohort study.

SETTING

Neonatal intensive care unit of Indus Hospital and Health Network, Karachi, Pakistan.

PATIENTS

All preterm neonates with RDS and who received HHHFT as primary respiratory support were included retrospectively, while neonates with orofacial anomalies, congenital heart and lung diseases other than RDS, abdominal wall defects, encephalopathy, congenital pneumonia and received continuous positive airway pressure or invasive ventilation were excluded.

INTERVENTIONS

HHHFT as primary respiratory support for RDS.

MAIN OUTCOME MEASURES

Effectiveness, duration, failure rate and complications of HHHFT as a primary respiratory support in moderate-late, very and extremely preterm neonates were evaluated.

RESULTS

The cohort included 138 neonates during a period of 12 months. The median gestational age was 32 weeks, and the median birth weight was 1607 g. Grade 1-2 RDS was seen in 97%, surfactant instillation was done in 10.8% and HHHFT was provided in all the neonates as primary respiratory support. The total duration of HHHFT support was <1 week in 94% of neonates. Bronchopulmonary dysplasia and pneumothorax until discharge or death were observed in one neonate, haemodynamically significant Patent Ductus Artriosus (HsPDA) in two neonates and intraventricular haemorrhage Grade ≥2 in five neonates, while only one neonate died.

CONCLUSION

This study appears to show that HHHFT is a simple, safe, efficient and cheap mode of primary respiratory support that can be given to spontaneously breathing moderate-late, very and extremely preterm neonates with RDS, especially in low- or middle-income countries.

Respiratory outcomes in preterm infants following intravitreal bevacizumab for retinopathy of prematurity-a 10-year matched case study

OBJECTIVES

To evaluate respiratory outcomes in preterm infants with retinopathy of prematurity (ROP) following intravitreal bevacizumab injection (IVB).

METHODS

This single-centre study enroled preterm infants with a gestational age (GA) < 34 weeks or a birth weight (BW) < 1500 g with bilateral type 1 ROP who received a single IVB, and a treatment-free control group matched by GA, postmenstrual age, and respiratory status at the time of the IVB. The primary outcome was serial respiratory changes in mean airway pressure (MAP), fraction of inspired oxygen (FiO2), and respiratory severity score (RSS, MAP x FiO2) during the 28-day post-IVB/matching period and overall respiratory improvement at day 28 and at discharge. The duration of supplemental oxygen therapy following IVB/matching was documented.

RESULTS

A total of 5578 infants were included. Seventy-eight infants were enroled in the IVB group, and another 78 infants were matched as the control group. Both groups had downward trends in the MAP, FiO2, and RSS over the study period (all P < 0.001), but there were no between-group differences in these measures. The percentage of overall respiratory improvement was similar between the IVB and control groups, so was the duration of invasive and in-hospital oxygen ventilation. A lower percentage of oxygen dependence at discharge in the IVB group (P = 0.03) remained significant after adjusting for GA and BW.

CONCLUSIONS

This is a matched case study to evaluate respiratory outcomes in preterm infants following IVB for ROP. We found that the IVBs did not compromise respiratory outcomes in preterm infants during the 28-day post-IVB period and at discharge.

Guidelines for high-flow nasal cannula oxygen therapy in neonates (2022)

High-flow nasal cannula (HFNC) oxygen therapy, which is important in noninvasive respiratory support, is increasingly being used in critically ill neonates with respiratory failure because it is comfortable, easy to setup, and has a low incidence of nasal trauma. The advantages, indications, and risks of HFNC have been the focus of research in recent years, resulting in the development of the application. Based on current evidence, we developed guidelines for HFNC in neonates using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). The guidelines were formulated after extensive consultations with neonatologists, respiratory therapists, nurse specialists, and evidence-based medicine experts. We have proposed 24 recommendations for 9 key questions. The guidelines aim to be a source of evidence and reference of HFNC oxygen therapy in clinical practice, and so that more neonates and their families will benefit from HFNC.

State of the art on neonatal noninvasive respiratory support: How physiological and technological principles explain the clinical outcomes

Noninvasive respiratory support has gained significant popularity in neonatal units because of its potential to reduce lung injury associated with invasive mechanical ventilation. To minimize lung injury, clinicians aim to apply for noninvasive respiratory support as early as possible. However, the physiological background and the technology behind such support modes are not always clear, and many open questions remain regarding the indications of use and clinical outcomes. This narrative review discusses the currently available evidence for various noninvasive respiratory support modes applied in Neonatal Medicine in terms of physiological effects and indications. Reviewed modes include nasal continuous positive airway pressure, nasal high-flow therapy, noninvasive high-frequency oscillatory ventilation, nasal intermittent positive pressure ventilation (NIPPV), synchronized NIPPV and noninvasive neurally adjusted ventilatory assist. To enhance clinicians' awareness of each support mode's strengths and limitations, we summarize technical features related to the functioning mechanisms of devices and the physical properties of the interfaces commonly used for providing noninvasive respiratory support to neonates. We finally address areas of current controversy and suggest possible areas of research for implementing noninvasive respiratory support in neonatal intensive care units.

French Neonatal Society issues recommendations on preventing nasal injuries in preterm newborn infants during non-invasive respiratory support

AIM

To issue practical recommendations regarding the optimal care of nasal skin when non-invasive ventilation support is used.

METHODS

We performed a systematic search of PubMed to identify relevant papers published in English or French through December 2019. Different grades of evidence were evaluated.

RESULTS

Forty-eight eligible studies. The incidence in preterm infants was high. The lesions were more frequent for preterm infants born under 30 weeks of gestational age and/or below 1500 g. The lesion was most often located on the skin of the nose but could also be found on the intranasal mucous membranes or elsewhere on the face. Nasal injuries appear early after the beginning of non-invasive ventilation at a mean of 2-3 days for cutaneous lesions and eight or nine for intranasal lesions. The most effective strategies to prevent trauma are the use of a hydrocolloid at the beginning of the support ventilation, the preferential use of a mask and the rotation of ventilation interfaces.

CONCLUSION

Nasal injuries with continuous positive airway pressure treatment in preterm newborn infants were frequent and can induce pain, discomfort and sequelae. The immature skin of preterm newborn infants needs specific attention from trained caregivers and awareness by parents.

Nasal high flow therapy for primary respiratory support in preterm infants

BACKGROUND

Nasal high flow (nHF) therapy provides heated, humidified air and oxygen via two small nasal prongs, at gas flows of more than 1 litre/minute (L/min), typically 2 L/min to 8 L/min. nHF is commonly used for non-invasive respiratory support in preterm neonates. It may be used in this population for primary respiratory support (avoiding, or prior to the use of mechanical ventilation via an endotracheal tube) for prophylaxis or treatment of respiratory distress syndrome (RDS). This is an update of a review first published in 2011 and updated in 2016.

OBJECTIVES

To evaluate the benefits and harms of nHF for primary respiratory support in preterm infants compared to other forms of non-invasive respiratory support.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date March 2022.

SELECTION CRITERIA

We included randomised or quasi-randomised trials comparing nHF with other forms of non-invasive respiratory support for preterm infants born less than 37 weeks' gestation with respiratory distress soon after birth.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane Neonatal methods. Our primary outcomes were 1. death (before hospital discharge) or bronchopulmonary dysplasia (BPD), 2. death (before hospital discharge), 3. BPD, 4. treatment failure within 72 hours of trial entry and 5. mechanical ventilation via an endotracheal tube within 72 hours of trial entry. Our secondary outcomes were 6. respiratory support, 7. complications and 8. neurosensory outcomes. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included 13 studies (2540 infants) in this updated review. There are nine studies awaiting classification and 13 ongoing studies. The included studies differed in the comparator treatment (continuous positive airway pressure (CPAP) or nasal intermittent positive pressure ventilation (NIPPV)), the devices for delivering nHF and the gas flows used. Some studies allowed the use of 'rescue' CPAP in the event of nHF treatment failure, prior to any mechanical ventilation, and some allowed surfactant administration via the INSURE (INtubation, SURfactant, Extubation) technique without this being deemed treatment failure. The studies included very few extremely preterm infants less than 28 weeks' gestation. Several studies had unclear or high risk of bias in one or more domains. Nasal high flow compared with continuous positive airway pressure for primary respiratory support in preterm infants Eleven studies compared nHF with CPAP for primary respiratory support in preterm infants. When compared with CPAP, nHF may result in little to no difference in the combined outcome of death or BPD (risk ratio (RR) 1.09, 95% confidence interval (CI) 0.74 to 1.60; risk difference (RD) 0, 95% CI -0.02 to 0.02; 7 studies, 1830 infants; low-certainty evidence). Compared with CPAP, nHF may result in little to no difference in the risk of death (RR 0.78, 95% CI 0.44 to 1.39; 9 studies, 2009 infants; low-certainty evidence), or BPD (RR 1.14, 95% CI 0.74 to 1.76; 8 studies, 1917 infants; low-certainty evidence). nHF likely results in an increase in treatment failure within 72 hours of trial entry (RR 1.70, 95% CI 1.41 to 2.06; RD 0.09, 95% CI 0.06 to 0.12; number needed to treat for an additional harmful outcome (NNTH) 11, 95% CI 8 to 17; 9 studies, 2042 infants; moderate-certainty evidence). However, nHF likely does not increase the rate of mechanical ventilation (RR 1.04, 95% CI 0.82 to 1.31; 9 studies, 2042 infants; moderate-certainty evidence). nHF likely results in a reduction in pneumothorax (RR 0.66, 95% CI 0.40 to 1.08; 10 studies, 2094 infants; moderate-certainty evidence) and nasal trauma (RR 0.49, 95% CI 0.36 to 0.68; RD -0.06, 95% CI -0.09 to -0.04; 7 studies, 1595 infants; moderate-certainty evidence). Nasal high flow compared with nasal intermittent positive pressure ventilation for primary respiratory support in preterm infants Four studies compared nHF with NIPPV for primary respiratory support in preterm infants. When compared with NIPPV, nHF may result in little to no difference in the combined outcome of death or BPD, but the evidence is very uncertain (RR 0.64, 95% CI 0.30 to 1.37; RD -0.05, 95% CI -0.14 to 0.04; 2 studies, 182 infants; very low-certainty evidence). nHF may result in little to no difference in the risk of death (RR 0.78, 95% CI 0.36 to 1.69; RD -0.02, 95% CI -0.10 to 0.05; 3 studies, 254 infants; low-certainty evidence). nHF likely results in little to no difference in the incidence of treatment failure within 72 hours of trial entry compared with NIPPV (RR 1.27, 95% CI 0.90 to 1.79; 4 studies, 343 infants; moderate-certainty evidence), or mechanical ventilation within 72 hours of trial entry (RR 0.91, 95% CI 0.62 to 1.33; 4 studies, 343 infants; moderate-certainty evidence). nHF likely results in a reduction in nasal trauma, compared with NIPPV (RR 0.21, 95% CI 0.09 to 0.47; RD -0.17, 95% CI -0.24 to -0.10; 3 studies, 272 infants; moderate-certainty evidence). nHF likely results in little to no difference in the rate of pneumothorax (RR 0.78, 95% CI 0.40 to 1.53; 4 studies, 344 infants; moderate-certainty evidence). Nasal high flow compared with ambient oxygen We found no studies examining this comparison. Nasal high flow compared with low flow nasal cannulae We found no studies examining this comparison.

AUTHORS' CONCLUSIONS

The use of nHF for primary respiratory support in preterm infants of 28 weeks' gestation or greater may result in little to no difference in death or BPD, compared with CPAP or NIPPV. nHF likely results in an increase in treatment failure within 72 hours of trial entry compared with CPAP; however, it likely does not increase the rate of mechanical ventilation. Compared with CPAP, nHF use likely results in less nasal trauma and likely a reduction in pneumothorax. As few extremely preterm infants less than 28 weeks' gestation were enrolled in the included trials, evidence is lacking for the use of nHF for primary respiratory support in this population.

Respiratory Management of the Preterm Infant: Supporting Evidence-Based Practice at the Bedside

Extremely preterm infants frequently require some form of respiratory assistance to facilitate the cardiopulmonary transition that occurs in the first hours of life. Current resuscitation guidelines identify as a primary determinant of overall newborn survival the establishment, immediately after birth, of adequate lung inflation and ventilation to ensure an adequate functional residual capacity. Any respiratory support provided, however, is an important contributing factor to the development of bronchopulmonary dysplasia. The risks correlated to invasive ventilatory techniques increase inversely with gestational age. Preterm infants are born at an early stage of lung development and are more susceptible to lung injury deriving from mechanical ventilation. Any approach aiming to reduce the global burden of preterm lung disease must implement lung-protective ventilation strategies that begin from the newborn’s first breaths in the delivery room. Neonatologists today must be able to manage both invasive and noninvasive forms of respiratory assistance to treat a spectrum of lung diseases ranging from acute to chronic conditions. We searched PubMed for articles on preterm infant respiratory assistance. Our narrative review provides an evidence-based overview on the respiratory management of preterm infants, especially in the acute phase of neonatal respiratory distress syndrome, starting from the delivery room and continuing in the neonatal intensive care unit, including a section regarding exogenous surfactant therapy.

European Consensus Guidelines on the Management of Respiratory Distress Syndrome: 2022 Update

Respiratory distress syndrome (RDS) care pathways evolve slowly as new evidence emerges. We report the sixth version of "European Guidelines for the Management of RDS" by a panel of experienced European neonatologists and an expert perinatal obstetrician based on available literature up to end of 2022. Optimising outcome for babies with RDS includes prediction of risk of preterm delivery, appropriate maternal transfer to a perinatal centre, and appropriate and timely use of antenatal steroids. Evidence-based lung-protective management includes initiation of non-invasive respiratory support from birth, judicious use of oxygen, early surfactant administration, caffeine therapy, and avoidance of intubation and mechanical ventilation where possible. Methods of ongoing non-invasive respiratory support have been further refined and may help reduce chronic lung disease. As technology for delivering mechanical ventilation improves, the risk of causing lung injury should decrease, although minimising time spent on mechanical ventilation by targeted use of postnatal corticosteroids remains essential. The general care of infants with RDS is also reviewed, including emphasis on appropriate cardiovascular support and judicious use of antibiotics as being important determinants of best outcome. We would like to dedicate this guideline to the memory of Professor Henry Halliday who died on November 12, 2022.These updated guidelines contain evidence from recent Cochrane reviews and medical literature since 2019. Strength of evidence supporting recommendations has been evaluated using the GRADE system. There are changes to some of the previous recommendations as well as some changes to the strength of evidence supporting recommendations that have not changed. This guideline has been endorsed by the European Society for Paediatric Research (ESPR) and the Union of European Neonatal and Perinatal Societies (UENPS).

Failure of early non-invasive ventilation in preterm infants with respiratory distress syndrome in current care practice in Spanish level-III neonatal intensive care units - a prospective observational study

Introduction

Despite advances in respiratory distress syndrome (RDS) management over the past decade, non-invasive ventilation (NIV) failure is frequent and associated with adverse outcomes. There are insufficient data on the failure of different NIV strategies currently used in clinical practice in preterm infants.

Methods

This was a prospective, multicenter, observational study of very preterm infants [gestational age (GA) <32 weeks] admitted to the neonatal intensive care unit for RDS that required NIV from the first 30 min after birth. The primary outcome was the incidence of NIV failure, defined as the need for mechanical ventilation for <72 h of life. Secondary outcomes were risk factors associated with NIV failure and complication rates.

Results

The study included 173 preterm infants with a median GA of 28 (IQR 27-30) weeks and a median birth weight of 1,100 (IQR 800-1,333) g. The incidence of NIV failure was 15.6%. In the multivariate analysis, lower GA (OR, 0.728; 95% CI, 0.576-0.920) independently increased the risk of NIV failure. Compared to NIV success, NIV failure was associated with higher rates of unfavorable outcomes, including pneumothorax, intraventricular hemorrhage, periventricular leukomalacia, pulmonary hemorrhage, and a combined outcome of moderate-to-severe bronchopulmonary dysplasia or death.

Conclusion

NIV failure occurred in 15.6% of the preterm neonates and was associated with adverse outcomes. The use of LISA and newer NIV modalities most likely accounts for the reduced failure rate. Gestational age remains the best predictor of NIV failure and is more reliable than the fraction of inspired oxygen during the first hour of life.

Surfactant Replacement Therapy: What’s the New Future?

Surfactant replacement therapy (SRT) can be lifesaving for preterm babies with respiratory distress because of surfactant deficiency. Attempts have been made over the last two decades to make surfactant administration as smooth and as nontraumatic as possible. Lesser invasive techniques, such as less invasive surfactant administration, minimally invasive surfactant therapy, intrapartum pharyngeal surfactant therapy, and the laryngeal mask airway, are preferred over invasive techniques like intubate surfactant extubation to reduce trauma and peridosing adverse effects. However, at present, aerosolized surfactant (AS) via nebulization remains the only truly noninvasive method of SRT. Many animal and human studies have shown promising results with the use of AS with similar clinical effects to an instilled surfactant with greater safety potential. But still AS has not been adapted to routine neonatal care. There is still scope for studies to further strengthen the role of AS. Also, SRT is a constantly changing field with new innovations revolutionizing and replacing old techniques.

Efficacy and Safety of Two Different Flow Rates of Nasal High-Flow Therapy in Preterm Neonates ≥28 Weeks of Gestation: A Randomized Controlled Trial

OBJECTIVE

The study aimed to compare the efficacy and safety of two different nasal high-flow rates for primary respiratory support in preterm neonates STUDY DESIGN:  In this single-center, double-blinded randomized controlled trial, preterm neonates ≥28 weeks of gestation with respiratory distress from birth were randomized to treatment with either increased nasal flow therapy (8-10 L/min) or standard nasal flow therapy (5-7 L/min). The primary outcome of nasal high-flow therapy failure was a composite outcome defined as the need for higher respiratory support (continuous positive airway pressure [CPAP] or mechanical ventilation) or surfactant therapy.

RESULTS

A total of 212 neonates were enrolled. Nasal high-flow failure rate in the increased flow group was similar to the standard flow group (22 vs. 29%, relative risk = 0.81 [95% confidence interval: 0.57-1.15]). However, nasal flow rate escalation was significantly more common in the standard flow group (64 vs. 43%, p = 0.004). None of the infants in the increased flow group developed air leak syndromes.

CONCLUSION

Higher nasal flow rate (8-10 L/min) when compared with lower nasal flow rate of 5 to 7 L/min did not reduce the need for higher respiratory support (CPAP/mechanical ventilation) or surfactant therapy in moderately and late preterm neonates. However, initial flow rates of 5 L/min were not optimal for most preterm infants receiving primary nasal flow therapy.

KEY POINTS

· Use of high nasal flows (8-10 L/min) did not reduce the need for higher respiratory support in moderately and late preterm infants.. · Nasal flow rate of 5 L/min was not optimal for most preterms with respiratory distress from birth.. · Careful patient selection and optimized flow settings could enhance nasal flow success in neonates..

Nasal high-flow therapy to Optimise Stability during Intubation: the NOSI pilot trial

OBJECTIVE

In adult patients with acute respiratory failure, nasal high-flow (NHF) therapy at the time of intubation can decrease the duration of hypoxia. The objective of this pilot study was to calculate duration of peripheral oxygen saturation below 75% during single and multiple intubation attempts in order to inform development of a larger definitive trial.

DESIGN AND SETTING

This double-blinded randomised controlled pilot trial was conducted at a single, tertiary neonatal centre from October 2020 to October 2021.

PARTICIPANTS

Infants undergoing oral intubation in neonatal intensive care were included. Infants with upper airway anomalies were excluded.

INTERVENTIONS

Infants were randomly assigned (1:1) to have NHF 6 L/min, FiO₂ 1.0 or NHF 0 L/min (control) applied during intubation, stratified by gestational age (<34 weeks vs ≥34 weeks).

MAIN OUTCOME MEASURES

The primary outcome was duration of hypoxaemia of <75% up to the time of successful intubation, RESULTS: 43 infants were enrolled (26 <34 weeks and 17 ≥34 weeks) with 50 intubation episodes. In infants <34 weeks' gestation, median duration of SpO₂ of <75% was 29 s (0-126 s) vs 43 s (0-132 s) (p=0.78, intervention vs control). Median duration of SpO_{2 of} <75% in babies ≥34 weeks' gestation was 0 (0-32 s) vs 0 (0-20 s) (p=0.9, intervention vs control).

CONCLUSION

This pilot study showed that it is feasible to provide NHF during intubation attempts. No significant differences were noted in duration of oxygen saturation of <75% between groups; however, this trial was not powered to detect a difference. A larger, higher-powered blinded study is warranted.

Diaphragm electrical activity during weaning of nasal high-flow therapy in preterm infants

OBJECTIVE

To determine whether electrical activity of the diaphragm (Edi) changes with weaning nasal high-flow (HF) therapy in preterm infants according to a standardised protocol.

DESIGN

Prospective observational cohort study.

SETTING

Neonatal intensive care unit.

PATIENTS

Preterm infants born at <32 weeks gestation, receiving nasal HF as part of routine clinical care.

INTERVENTIONS

Infants recruited to the study had their HF weaned according to set clinical criteria. Edi was measured using a modified gastric feeding tube serially from baseline (pre-wean) to 24-hours post-wean.

MAIN OUTCOME MEASURES

Change in Edi from baseline was measured at four time points up to 24 hours after weaning. Minimum Edi during expiration, maximum Edi during inspiration and amplitude of the Edi signal (Edi_delta) were measured. Clinical parameters (heart rate, respiratory rate and fraction of inspired oxygen) were also recorded.

RESULTS

Forty preterm infants were recruited at a mean corrected gestational age of 31.6 (±2.7) weeks. Data from 156 weaning steps were analysed, 91% of which were successful. Edi did not change significantly from baseline during flow reduction steps, but a significant increase in diaphragm activity was observed when discontinuing HF (median increase in Edi_delta immediately post-discontinuation 1.7 µV (95% CI: 0.6 to 3.0)) and at 24 hours 1.9 µV (95% CI: 0.7 to 3.8)). No significant difference in diaphragm activity was observed between successful and unsuccessful weaning steps.

CONCLUSIONS

A protocolised approach to weaning has a high probability of success. Edi does not change with reducing HF rate, but significantly increases with discontinuation of HF from 2 L/min.

Recent advances in the use of high flow nasal oxygen therapies

High flow nasal oxygen is a relatively new option for treating patients with respiratory failure, which decreases work of breathing, improves tidal volume, and modestly increases positive end expiratory pressure. Despite well-described physiologic benefits, the clinical impact of high flow nasal oxygen is still under investigation. In this article, we review the most recent findings on the clinical efficacy of high flow nasal oxygen in Type I, II, III, and IV respiratory failure within adult and pediatric patients. Additionally, we discuss studies across clinical settings, including emergency departments, intensive care units, outpatient, and procedural settings.

Non-invasive respiratory support in preterm infants

Survival of preterm infants has increased steadily over recent decades, primarily due to improved outcomes for those born before 28 weeks of gestation. However, this has not been matched by similar improvements in longer-term morbidity. One of the key long-term sequelae of preterm birth remains bronchopulmonary dysplasia (also called chronic lung disease of prematurity), contributed primarily by the effect of early pulmonary inflammation superimposed on immature lungs. Non-invasive modes of respiratory support have been rapidly introduced providing modest success in reducing the incidence of bronchopulmonary dysplasia when compared with invasive mechanical ventilation, and improved clinical practice has been reported from population-based studies. We present a comprehensive review of the key modes of non-invasive respiratory support currently used in preterm infants, including their mechanisms of action and evidence of benefit from clinical trials.

Mortality after 36 weeks postmenstrual age of extremely preterm infants in neonatal care: The impact of growth impairment and bronchopulmonary dysplasia

BACKGROUND

A small group of extremely preterm infants survive to 36 weeks postmenstrual age (PMA), but die before discharge from neonatal care.

AIMS

To investigate which epidemiological and clinical parameters were related to death after 36 weeks PMA in extremely preterm infants.

STUDY DESIGN

Retrospective whole-population study.

SUBJECTS

All infants born <28 weeks of gestation admitted to a neonatal unit in England between 2014 and 2018.

OUTCOME MEASURES

Mortality after 36 weeks PMA and before discharge from neonatal care. Bronchopulmonary dysplasia (BPD) defined as any respiratory support at 36 weeks PMA.

RESULTS

Death after 36 weeks PMA occurred in 156 of a total of 11.747 included infants (1.3 %) and at a median (IQR) age of 130 (93-164) days. A lower gestational age [Odds Ratio: 0.82, 95 % CI:0.72-0.94, adjusted p = 0.005], lower birth weight z-score [Odds Ratio: 0.45, 95 % CI:0.36-0.56, adjusted p < 0.001], greater absolute difference in weight z-score from birth to 36 weeks PMA [Odds Ratio: 0.46, 95 % CI:0.38-0.56, adjusted p < 0.001] were independently associated with death after 36 weeks PMA. A diagnosis of BPD [Odds Ratio: 4.57, 95 % CI:2.19-9.54, adjusted p < 0.001] and of necrotising enterocolitis requiring surgery [Odds Ratio: 2.81, 95 % CI:1.82-4.34, adjusted p < 0.001] were also independently associated with death after 36 weeks PMA.

CONCLUSIONS

Mortality of extremely preterm infants after 36 weeks postmenstrual age is associated with lower gestational age and more impaired growth. The diagnoses of bronchopulmonary dysplasia and necrotising enterocolitis were associated with a higher risk of death after 36 weeks postmenstrual age and before discharge from neonatal care.

Delivery Room Respiratory Stabilization of Preterm Neonates: A Randomized, Controlled Trial

OBJECTIVE

To determine whether heated humidified high-flow nasal cannula (HHHFNC) is noninferior to NCPAP to provide DR respiratory support to preterm neonates of gestational age (GA) 28-36 wk.

METHODS

This randomized, controlled, noninferiority trial included 124 spontaneously breathing preterm neonates who developed respiratory distress soon after birth and/or had a FiO₂ requirement > 0.3. Primary outcome measure was treatment failure within 24 h. The absolute risk difference with 95% confidence interval (CI) were calculated with a noninferiority margin of 10%. Secondary outcome variables were temperature at admission, time to treatment failure, treatment failure at 72 h, need for surfactant, intubation, duration of respiratory support, and incidences of adverse events including mortality. Intention-to-treat analysis was done in Stata software.

RESULTS

Both the groups were similar in baseline characteristics. There was no statistically significant difference between the treatment failure rates with HHHFNC (13.1%, n = 61) and NCPAP (11.1%, n = 63) (risk difference 2.0%, 95% CI - 9.9% to 14.07%, p = 0.73). However, noninferiority of HHHFNC to NCPAP could not be conclusively proved as the 95% CI crossed both 0 and the noninferiority margin of 10%. There were no significant differences in secondary outcomes.

CONCLUSIONS

HHHFNC showed similar efficacy and safety as NCPAP irrespective of gestational age, though its noninferiority to NCPAP remained inconclusive.

TRIAL REGISTRATION

Clinical Trial Registry of India, Registration no: CTRI/2019/10/021633, https://ctri.icmr.org.in/.

A randomised trial comparing weaning from CPAP alone with weaning using heated humidified high flow nasal cannula in very preterm infants: the CHiPS study

OBJECTIVE

To determine whether weaning from nasal continuous positive airway pressure (nCPAP) using heated humidified high flow nasal cannula (nHF) was non-inferior to weaning using nCPAP alone in relation to time on respiratory support.

STUDY DESIGN

Single-centre, non-inferiority, randomised controlled trial.

SETTING

Neonatal Intensive Care Unit, Middlemore Hospital, Auckland, New Zealand.

PATIENTS

120 preterm infants, <30 weeks' gestation at birth, stable on nCPAP for at least 48 hours.

INTERVENTIONS

Infants underwent stratified randomisation to nHF 6 L/min or bubble CPAP 6 cm water. In both groups, stepwise weaning of their respiratory support over 96 hours according to a strict weaning protocol was carried out.

MAIN OUTCOME MEASURES

Time on respiratory support from randomisation to 72 hours off respiratory support or 36 weeks' postmenstrual age. The non-inferiority threshold was set at 15%.

RESULTS

59 infants were randomised to weaning using nHF and 61 using nCPAP. The groups were well balanced in regards to baseline demographics. The restricted mean duration of respiratory support following randomisation for the nCPAP group, using per-protocol analysis was 401 hours (upper boundary, mean plus 0.15, was 461 hours) and 375 hours in the nHF group (upper 95% CI 413 hours). nHF weaning was, therefore, non-inferior to nCPAP weaning at the non-inferiority threshold. There was no significant difference in time to discharge.

CONCLUSION

For infants ready to wean from nCPAP, the CHiPS study found that nHF was non-inferior to discontinuing nCPAP at 5 cm water.

TRIAL REGISTRATION NUMBER

Australia and New Zealand Clinical Trials Registry (ACTRN12615000077561).

Effect of High-Flow Nasal Cannula Therapy vs Continuous Positive Airway Pressure Therapy on Liberation From Respiratory Support in Acutely Ill Children Admitted to Pediatric Critical Care Units: A Randomized Clinical Trial

IMPORTANCE

The optimal first-line mode of noninvasive respiratory support for acutely ill children is not known.

OBJECTIVE

To evaluate the noninferiority of high-flow nasal cannula therapy (HFNC) as the first-line mode of noninvasive respiratory support for acute illness, compared with continuous positive airway pressure (CPAP), for time to liberation from all forms of respiratory support.

DESIGN, SETTING, AND PARTICIPANTS

Pragmatic, multicenter, randomized noninferiority clinical trial conducted in 24 pediatric critical care units in the United Kingdom among 600 acutely ill children aged 0 to 15 years who were clinically assessed to require noninvasive respiratory support, recruited between August 2019 and November 2021, with last follow-up completed in March 2022.

INTERVENTIONS

Patients were randomized 1:1 to commence either HFNC at a flow rate based on patient weight (n = 301) or CPAP of 7 to 8 cm H2O (n = 299).

MAIN OUTCOMES AND MEASURES

The primary outcome was time from randomization to liberation from respiratory support, defined as the start of a 48-hour period during which a participant was free from all forms of respiratory support (invasive or noninvasive), assessed against a noninferiority margin of an adjusted hazard ratio of 0.75. Seven secondary outcomes were assessed, including mortality at critical care unit discharge, intubation within 48 hours, and use of sedation.

RESULTS

Of the 600 randomized children, consent was not obtained for 5 (HFNC: 1; CPAP: 4) and respiratory support was not started in 22 (HFNC: 5; CPAP: 17); 573 children (HFNC: 295; CPAP: 278) were included in the primary analysis (median age, 9 months; 226 girls [39%]). The median time to liberation in the HFNC group was 52.9 hours (95% CI, 46.0-60.9 hours) vs 47.9 hours (95% CI, 40.5-55.7 hours) in the CPAP group (absolute difference, 5.0 hours [95% CI -10.1 to 17.4 hours]; adjusted hazard ratio 1.03 [1-sided 97.5% CI, 0.86-∞]). This met the criterion for noninferiority. Of the 7 prespecified secondary outcomes, 3 were significantly lower in the HFNC group: use of sedation (27.7% vs 37%; adjusted odds ratio, 0.59 [95% CI, 0.39-0.88]); mean duration of critical care stay (5 days vs 7.4 days; adjusted mean difference, -3 days [95% CI, -5.1 to -1 days]); and mean duration of acute hospital stay (13.8 days vs 19.5 days; adjusted mean difference, -7.6 days [95% CI, -13.2 to -1.9 days]). The most common adverse event was nasal trauma (HFNC: 6/295 [2.0%]; CPAP: 18/278 [6.5%]).

CONCLUSIONS AND RELEVANCE

Among acutely ill children clinically assessed to require noninvasive respiratory support in a pediatric critical care unit, HFNC compared with CPAP met the criterion for noninferiority for time to liberation from respiratory support.

TRIAL REGISTRATION

ISRCTN.org Identifier: ISRCTN60048867.

Post-INSURE Administration of Heated Humidified High-Flow Therapy Versus Nasal Continuous Positive Airway Pressure in Preterm Infants More Than 28 Weeks Gestation with Respiratory Distress Syndrome: A Randomized Non-Inferiority Trial

In preterm infants with respiratory distress syndrome (RDS), non-invasive ventilation (NIV) is usually provided using nasal continuous positive airway pressure (NCPAP) or non-invasive mechanical ventilation after surfactant administration by INtubation-SURfactant-Extubation (INSURE) method. Heated humidified high-flow nasal cannula (HHHFNC) is a mode of NIV with advantages of ease of application, less grades of nasal injury and easy handling. This study was done to compare the effectiveness of HHHFNC therapy administration as post-INSURE respiratory support in preterm infants as compared to NCPAP. The primary outcome was to compare the rate of treatment failure within 7 days of randomization to HHHFNC or NCPAP as a post-INSURE ventilatory modality. It was a pilot trial wherein all preterm infants more than 1 kg and more than 28 weeks gestational age with RDS who required surfactant were randomized to receive NCPAP or HHHFNC. Infants with an urgent need for intubation and mechanical ventilation were considered to have treatment failure. Thirty babies were enrolled-15 in each group. Baseline demographic characteristics were comparable. There was no significant difference in the primary outcome of early failure rate, i.e. mechanical ventilation rate within 7 days of starting treatment. There were no significant differences in other outcomes except nasal injury which was significantly lesser in the HHHFNC group. In conclusion, HHHFNC appears to be non-inferior to NCPAP when used in preterm infants more than 28 weeks gestation with RDS as a post-INSURE ventilatory modality.

Preclinical Assessment of Nebulized Surfactant Delivered through Neonatal High Flow Nasal Cannula Respiratory Support

High-flow nasal cannula (HFNC) is a non-invasive respiratory support (NRS) modality to treat premature infants with respiratory distress syndrome (RDS). The delivery of nebulized surfactant during NRS would represent a truly non-invasive method of surfactant administration and could reduce NRS failure rates. However, the delivery efficiency of nebulized surfactant during HFNC has not been evaluated in vitro or in animal models of respiratory distress. We, therefore, performed first a benchmark study to compare the surfactant lung dose delivered by commercially available neonatal nasal cannulas (NCs) and HFNC circuits commonly used in neonatal intensive care units. Then, the pulmonary effect of nebulized surfactant delivered via HFNC was investigated in spontaneously breathing rabbits with induced respiratory distress. The benchmark study revealed the surfactant lung dose to be relatively low for both types of NCs tested (Westmed NCs 0.5 ± 0.45%; Fisher & Paykel NCs 1.8 ± 1.9% of a nominal dose of 200 mg/kg of Poractant alfa). The modest lung doses achieved in the benchmark study are compatible with the lack of the effect of nebulized surfactant in vivo (400 mg/kg), where arterial oxygenation and lung mechanics did not improve and were significantly worse than the intratracheal instillation of surfactant. The results from the present study indicate a relatively low lung surfactant dose and negligible effect on pulmonary function in terms of arterial oxygenation and lung mechanics. This negligible effect can, for the greater part, be explained by the high impaction of aerosol particles in the ventilation circuit and upper airways due to the high air flows used during HFNC.

Implementation of neurally adjusted ventilatory assist and high flow nasal cannula in very preterm infants in a tertiary level NICU

Preterm infants treated with invasive ventilation are often affected by bronchopulmonary dysplasia, brain structure alterations, and later neurodevelopmental impairment. We studied the implementation of neurally adjusted ventilatory assist (NAVA) and high flow nasal cannula (HFNC) in a level III neonatal unit, and its effects on pulmonary and central nervous system outcomes. This retrospective cohort study included 193 surviving infants born below 32 weeks of gestation in preimplementation (2007-2008) and postimplementation (2016-2017) periods in a single study center in Finland. The proportion of infants requiring invasive ventilation decreased from 67% in the pre- to 48% in the postimplementation period (p = 0.009). Among infants treated with invasive ventilation, 68% were treated with NAVA after its implementation. At the same time, the duration of invasive ventilation of infants born at or below 28 weeks increased threefold compared with the preimplementation period (p = 0.042). The postimplementation period was characterized by a gradual replacement of nasal continuous positive airway pressure (nCPAP) with HFNC, earlier discontinuation of nCPAP, but a longer duration of positive pressure support. The proportion of normal magnetic resonance imaging (MRI) findings at term corrected age increased from 62% to 84% (p = 0.018). Cognitive outcome improved by one standard score between the study periods (p = 0.019). NAVA was used as the primary mode of ventilation in the postimplementation period. During this period, invasive ventilation time was significantly prolonged. HFNC led to a decrease in the use of nCPAP. The change in the respiratory support might have contributed to the improvement in brain MRI findings and cognitive outcomes.

Effect of High-Flow Nasal Cannula Therapy vs Continuous Positive Airway Pressure Following Extubation on Liberation From Respiratory Support in Critically Ill Children: A Randomized Clinical Trial

IMPORTANCE

The optimal first-line mode of noninvasive respiratory support following extubation of critically ill children is not known.

OBJECTIVE

To evaluate the noninferiority of high-flow nasal cannula (HFNC) therapy as the first-line mode of noninvasive respiratory support following extubation, compared with continuous positive airway pressure (CPAP), on time to liberation from respiratory support.

DESIGN, SETTING, AND PARTICIPANTS

This was a pragmatic, multicenter, randomized, noninferiority trial conducted at 22 pediatric intensive care units in the United Kingdom. Six hundred children aged 0 to 15 years clinically assessed to require noninvasive respiratory support within 72 hours of extubation were recruited between August 8, 2019, and May 18, 2020, with last follow-up completed on November 22, 2020.

INTERVENTIONS

Patients were randomized 1:1 to start either HFNC at a flow rate based on patient weight (n = 299) or CPAP of 7 to 8 cm H2O (n = 301).

MAIN OUTCOMES AND MEASURES

The primary outcome was time from randomization to liberation from respiratory support, defined as the start of a 48-hour period during which the child was free from all forms of respiratory support (invasive or noninvasive), assessed against a noninferiority margin of an adjusted hazard ratio (HR) of 0.75. There were 6 secondary outcomes, including mortality at day 180 and reintubation within 48 hours.

RESULTS

Of the 600 children who were randomized, 553 children (HFNC, 281; CPAP, 272) were included in the primary analysis (median age, 3 months; 241 girls [44%]). HFNC failed to meet noninferiority, with a median time to liberation of 50.5 hours (95% CI, 43.0-67.9) vs 42.9 hours (95% CI, 30.5-48.2) for CPAP (adjusted HR, 0.83; 1-sided 97.5% CI, 0.70-∞). Similar results were seen across prespecified subgroups. Of the 6 prespecified secondary outcomes, 5 showed no significant difference, including the rate of reintubation within 48 hours (13.3% for HFNC vs 11.5 % for CPAP). Mortality at day 180 was significantly higher for HFNC (5.6% vs 2.4% for CPAP; adjusted odds ratio, 3.07 [95% CI, 1.1-8.8]). The most common adverse events were abdominal distension (HFNC: 8/281 [2.8%] vs CPAP: 7/272 [2.6%]) and nasal/facial trauma (HFNC: 14/281 [5.0%] vs CPAP: 15/272 [5.5%]).

CONCLUSIONS AND RELEVANCE

Among critically ill children requiring noninvasive respiratory support following extubation, HFNC compared with CPAP following extubation failed to meet the criterion for noninferiority for time to liberation from respiratory support.

TRIAL REGISTRATION

isrctn.org Identifier: ISRCTN60048867.

Perinatal care for the extremely preterm infant

Being born preterm (prior to 37 weeks of completed gestation) is a leading cause of childhood death up to five years of age, and is responsible for the demise of around one million preterm infants each year. Rates of prematurity, which range from approximately 5 to 18% of births, are increasing in most countries. Babies born extremely preterm (less than 28 weeks' gestation) and in particular, in the periviable (20^0/7-25^6/7 weeks) period, are at the highest risk of death, or the development of long-term disabilities. The perinatal care of extremely preterm infants and their mothers raises a number of clinical, technical, and ethical challenges. Focusing on 'micropremmies', or those born in the periviable period, this paper provides an update regarding the aetiology and impacts of periviable preterm birth, advances in the antenatal, intrapartum, and acute post-natal management of these infants, and a review of counselling/support approaches for engaging with the infant's family. It concludes with an overview of emerging technology that may assist in improving outcomes for this at-risk population.

Observational cohort study of changing trends in non-invasive ventilation in very preterm infants and associations with clinical outcomes

OBJECTIVE

To determine the change in non-invasive ventilation (NIV) use over time in infants born at <32 weeks' gestation and the associated clinical outcomes.

STUDY DESIGN

Retrospective cohort study using routinely recorded data from the National Neonatal Research Database of infants born at <32 weeks admitted to neonatal units in England and Wales from 2010 to 2017.

RESULTS

In 56 537 infants, NIV use increased significantly between 2010 and 2017 (continuous positive airway pressure (CPAP) from 68.5% to 80.2% in 2017 and high flow nasal cannula (HFNC) from 14% to 68%, respectively) (p<0.001)). Use of NIV as the initial mode of respiratory support also increased (CPAP, 21.5%-28.0%; HFNC, 1%-7% (p<0.001)).HFNC was used earlier, and for longer, in those who received CPAP or mechanical ventilation. HFNC use was associated with decreased odds of death before discharge (adjusted OR (aOR) 0.19, 95% CI 0.17 to 0.22). Infants receiving CPAP but no HFNC died at an earlier median chronological age: CPAP group, 22 (IQR 10-39) days; HFNC group 40 (20-76) days (p<0.001). Among survivors, HFNC use was associated with increased odds of bronchopulmonary dysplasia (BPD) (aOR 2.98, 95% CI 2.81 to 3.15) and other adverse outcomes.

CONCLUSIONS

NIV use is increasing, particularly as initial respiratory support. HFNC use has increased significantly with a sevenfold increase soon after birth which was associated with higher rates of BPD. As more infants survive with BPD, we need robust clinical evidence, to improve outcomes with the use of NIV as initial and ongoing respiratory support.

Update on ventilatory management of extremely preterm infants-A Neonatal Intensive Care Unit perspective

Extremely preterm infants commonly suffer from respiratory distress syndrome. Ventilatory management of these infants starts from birth and includes decisions such as timing of respiratory support in relation to umbilical cord management, oxygenation targets, and options of positive pressure support. The approach of early intubation and surfactant administration through an endotracheal tube has been challenged in recent years by primary noninvasive respiratory support and newer methods of surfactant administration via thin catheters. Available data comparing the thin catheter method to endotracheal tube and delayed extubation in extremely preterm infants born before 28 weeks of gestation did not show differences in survival free of bronchopulmonary dysplasia. Data from numerous randomized trials comparing conventional ventilation with high-frequency oscillatory ventilation did not show differences in meaningful outcomes. Among conventional modes of ventilation, there is good evidence to favor volume-targeted ventilation over pressure-limited ventilation. The former reduces the combined risk of bronchopulmonary dysplasia or death and several important secondary outcomes without an increase in adverse events. There are no evidence-based guidelines to set positive end-expiratory pressure in ventilated preterm infants. Recent research suggests that the forced oscillation technique may help to find the lowest positive end-expiratory pressure at which lung recruitment is optimal. Benefits and risks of the various modes of noninvasive ventilation depend on the clinical setting, degree of prematurity, severity of lung disease, and competency of staff in treating associated complications. Respiratory care after discharge includes home oxygen therapy, lung function monitoring, weaning from medication started in the neonatal unit, and treatment of asthma-like symptoms.

Systematic review of high-flow nasal cannula versus continuous positive airway pressure for primary support in preterm infants

INTRODUCTION

We conducted a meta-analysis of trials that compared efficacy and safety of high-flow nasal cannula (HFNC) with continuous positive airway pressure (CPAP) as primary respiratory support in preterm infants and a study of the impact of clinical relevant parameters.

METHODS

Databases were searched for randomised controlled trials comparing HFNC with CPAP as primary respiratory support in preterm infants. Treatment failure was considered as primary outcome and adverse events as secondary outcomes. We calculated risk ratios (RRs) in intention-to-treat analysis and random-effects meta-analyses of risks were conducted.

RESULTS

We included 10 studies for a total of 1830 patients. Meta-analysis demonstrated an RR of treatment failure multiplied by 1.34 using HFNC compared with CPAP (RR=1.34, 95% CI 1.01 to 1.68, I²=16.2%). Secondary outcome meta-analysis showed no difference in intubation rates (RR=0.90, 95% CI 0.66 to 1.15) and a lower rate of nasal trauma using HFNC compared with CPAP (RR=0.48, 95% CI 0.31 to 0.65, I²=0.0%). Meta-regressions did not show any influence of gestational age and weight at birth, HFNC flow rate, type of CPAP generator or use of surfactant.

CONCLUSIONS

Despite a higher risk of treatment failure, considering no difference in intubation rates and a lower rate of nasal trauma using HFNC compared with CPAP, we suggest that HFNC should be used as primary respiratory support in preterm infants.

Are we enrolling representative cohorts of premature infants in our clinical trials?

OBJECTIVE

To compare the difference in outcomes in a subset population of infants "eligible but not enrolled; ENE" vs those who were "eligible and enrolled, EE" in The Australian Placental Transfusion Study (APTS).

STUDY DESIGN

Population-based multicentre retrospective cohort study.

RESULTS

A total of 535 (17.7%) infants were categorized as EE and 2489 (82.3%) ENE. ENE infants were significantly more premature (mean gestation 27.0 vs 28.0 weeks) but otherwise of similar anthropometric measures compared to EE infants. ENE infants had significantly higher incidences of low Apgar scores <7 at 5 min, CLD, IVH and PDA requiring treatment. Using a multivariate adjusted-analysis, ENE were at a greater risk for mortality (OR 1.86; 95% CI, 1.30-2.67, p < 0.001).

CONCLUSION

Antenatal consenting may lead to biased population representation, which may affect trial results' generalizability. Retrospective consent or waiver of consent may improve the generalizability of neonatal and emergency clinical trials.

High-flow nasal cannula versus continuous positive airway pressure in primary respiratory support for preterm infants: A systematic review and meta-analysis

Respiratory support is crucial for the survival of preterm infants, and High-flow Nasal Cannula Oxygen Therapy (HFNC) and Continuous Positive Airway Pressure (CPAP) are commonly used for neonatal respiratory support. This meta-analysis aimed to compare the effects of HFNC and CPAP in primary respiratory support for preterm infants, to provide evidence-based support for clinical practice. PubMed, Embase, Cochrane Library, ClinicalTrials.gov, CNKI, VIP, WANFANG and SinoMed were searched for eligible studies. The primary outcomes included the incidence of treatment failure and the application of mechanical ventilation. A total of 27 eligible studies with 3,351 participants were included. There was no significant difference in the incidence of respiratory support failure [RR = 1.17, 95%CI (0.88-1.56)] and the application of mechanical ventilation [RR = 1.00, 95%CI (0.84-1.19)] between HFNC group and CPAP group. HFNC resulted in lower rate of air leaks [RR = 0.65, 95%CI (0.46-0.92)], nasal trauma [RR = 0.36, 95%CI (0.29-0.45)] and abdominal distension [RR = 0.39, 95%CI (0.27-0.58)], and later time of mechanical ventilation initiating [SMD = 0.60, 95%CI (0.21-0.99)], less duration of oxygen therapy [SMD = -0.35, 95%CI (-0.68 to -0.02)] and earlier enteral feeding [SMD = -0.54, 95%CI (-0.95 to -0.13)]. Alternative non-invasive respiratory support after initial treatment failure resulted in no difference in the application of mechanical ventilation between the two groups [RR = 0.99, 95%CI (0.52-1.88)]. HFNC might be more effective and safer in primary respiratory support for preterm infants. Using CPAP as a remedy for the treatment failure of HFNC could not avoid intubation. For premature infants with the gestational age <28 weeks, HFNC as primary respiratory support still needs to be further elucidated. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022313479, identifier: CRD42022313479.

Deferred Consent in Neonatal Clinical Research: Why, When, How?

Deferred consent has gained traction in some countries as a possible adjunct to prospective consent for evaluating emergency therapies in the neonatal population. This form of consent has been shown to increase recruitment of acutely and critically unwell patients, potentially reduce parent decision-making burden, and provide more robust evidence for clinical treatments where equipoise exists. However, deferred consent raises complex ethical concerns and guidelines for its use vary across different jurisdictions. The views of all stakeholders, including neonatal providers and parents, are important in determining the appropriateness of deferred consent in high-risk patients. Deferred consent may be ethically justifiable for assessing various treatments, particularly those used in emergency medical management. We present a framework based on neonatal deferred consent trials that assess both non-drug and drug interventions, our experience conducting deferred consent neonatal studies in Australia, and the views of providers and parents on how to best implement deferred consent in the neonatal research setting.

A Review of High Flow Nasal Cannula Oxygen Therapy in Human and Veterinary Medicine

Respiratory distress is a common ailment in small animal medicine. Oxygen supplementation is a mainstay of initial therapy. High Flow Nasal Cannula Oxygen Therapy (HFNCOT) has become increasingly popular as a treatment modality in human medicine, and more recently in canine patients. These devices deliver high flow rates of heated and humidified oxygen at an adjustable fraction of inspired oxygen (FiO₂). This article reviews current literature in human patients on HFNCOT as well as studies that have evaluated its use in veterinary patients. A discussion of the respiratory physiology that is associated with respiratory distress, in addition to an overview of currently available oxygen supplementation modalities is provided. The physiologic benefits of HFNCOT are explained, as are technical aspects associated with its use. Recommendations on initial settings, maintenance therapy, and weaning are also described.

The Intertemporal Role of Respiratory Support in Improving Neonatal Outcomes: A Narrative Review

Defining improvements in healthcare can be challenging due to the need to assess multiple outcomes and measures. In neonates, although progress in respiratory support has been a key factor in improving survival, the same degree of improvement has not been documented in certain outcomes, such as bronchopulmonary dysplasia. By exploring the evolution of neonatal respiratory care over the last 60 years, this review highlights not only the scientific advances that occurred with the application of invasive mechanical ventilation but also the weakness of the existing knowledge. The contributing role of non-invasive ventilation and less-invasive surfactant administration methods as well as of certain pharmacological therapies is also discussed. Moreover, we analyze the cost-benefit of neonatal care-respiratory support and present future challenges and perspectives.

Risk factors for treatment failure of heated humidified high-flow nasal cannula as initial respiratory support for preterm infants

OBJECTIVES

To study the risk factors for treatment failure of heated humidified high-flow nasal cannula (HHHFNC) as initial respiratory support for preterm infants.

METHODS

A retrospective analysis was performed on the medical data of the preterm infants who were admitted from January 2018 to April 2021 and received HHHFNC for initial respiratory support after birth. According to whether it was necessary to upgrade to noninvasive continuous positive airway pressure or invasive mechanical ventilation within 72 hours after treatment, they were divided into a failure group and a success group. Univariate and multivariate logistic regression analyses were used to determine the risk factors for failure of HHHFNC as initial respiratory support.

RESULTS

A total of 166 preterm infants were included, among whom 48 (28.9%) experienced the treatment failure of HHHNFC as initial respiratory support. The univariate analysis showed that compared with the success group with 118 infants, the failure group had significantly lower gestational age and birth weight and a significantly higher proportion of infants with fraction of inspired oxygen >35%, flow rate >6 L/minute, patent ductus arteriosus (PDA), respiratory distress syndrome (RDS), or use of pulmonary surfactant (P<0.05). The multivariate logistic regression analysis showed that gestational age <32 weeks, PDA (>1.5 mm and left atrium/aorta diameter ratio >1.4), fraction of inspired oxygen >35%, flow rate >6 L/minute, and presence of RDS were risk factors for the treatment failure of HHHNFC as initial respiratory support (P<0.05).

CONCLUSIONS

The preterm infants with a gestational age of <32 weeks or the presence of RDS tend to have a high risk of failure of HHHNFC as initial respiratory support. The risk of failure of HHHFNC as initial respiratory support increases in infants with oxygen concentration >35% and/or flow rate >6 L/minute, or the presence of PDA, suggesting an upgrade of respiratory support should be considered. Citation.

A Comparison of Moderate to Late Preterm Neonates Receiving Nasal Continuous Positive Airway Pressure in Australian Tertiary and Nontertiary Centers

PURPOSE

Transfer of neonates ≥32 weeks' gestation with acute respiratory distress to tertiary (T) centers can be reduced by treatment with nasal continuous positive airway pressure (nCPAP) in nontertiary (NT) centers. This can lead to considerable financial and emotional benefits. The aim of this project was to compare management of nCPAP in T and NT centers.

DESIGN

Five-year retrospective, observational cohort study (2010-2014).

SAMPLE

All NT eligible neonates from four sites (n = 484) were compared with a similar randomized cohort of inborn neonates at two T centers (n = 601) in Victoria, Australia.

MAIN OUTCOME VARIABLE

Any difference in management or short-term outcome.

RESULTS

Moderately preterm and term neonates born in NT centers had lower Apgar scores at five minutes of age and received more conservative management delivered by different equipment. Despite a higher incidence of air leaks in NT centers, the short-term outcomes were otherwise similar between centers. T centers were more likely to administer nCPAP to term babies for <24 hours.

Cost-Effectiveness of Nasal High Flow Versus CPAP for Newborn Infants in Special-Care Nurseries

BACKGROUND

Treating respiratory distress in newborns is expensive. We compared the cost-effectiveness of 2 common noninvasive therapies, nasal continuous positive airway pressure (CPAP) and nasal high-flow (nHF), for newborn infants cared for in nontertiary special care nurseries.

METHODS

The economic evaluation was planned alongside a randomized control trial conducted in 9 Australian special care nurseries. Costs were considered from a hospital perspective until infants were 12 months of age. A total of 754 infants with respiratory distress, born ≥31 weeks' gestation and with birth weight ≥1200 g, <24 hours old, requiring noninvasive respiratory support and/or supplemental oxygen for >1 hour were recruited during 2015-2017. Inpatient costing records were obtained for 753 infants, of whom 676 were included in the per-protocol analysis. Two scenarios were considered: (1) CPAP versus nHF, with infants in the nHF group having "rescue" CPAP backup available (trial scenario); and (2) CPAP versus nHF, as sole primary support (hypothetical scenario). Effectiveness outcomes were rate of endotracheal intubation and transfer to a tertiary-level NICU.

RESULTS

As sole primary support, CPAP is more effective and on average cheaper, and thus is superior. However, nHF with back-up CPAP produced equivalent cost and effectiveness results, and there is no reason to make a decision between the 2 treatments on the basis of the cost or effectiveness outcomes.

CONCLUSIONS

Nontertiary special care nurseries choosing to use only 1 of the modes should choose CPAP. In units with both modes available, using nHF as first-line therapy may be acceptable if there is back-up CPAP.

Cerebral oxygenation is stable in preterm infants transitioning to heated humidified high-flow nasal cannula therapy

AIM

To assess cerebral oxygenation in premature infants who are transitioning from nasal continuous positive airway pressure (nCPAP) to heated humidified high-flow nasal cannula therapy (HFNC).

METHODS

A prospective observational study done in a single-centre neonatal intensive care unit (NICU). Regional cerebral oxygen saturations (RcSO₂ ) were measured using frequency-domain near-infrared spectroscopy (FD-NIRS) in very low birthweight (VLBW) premature infants born at <32 weeks transitioning from nCPAP to HFNC.

RESULTS

Median gestational age was 27 weeks and median birthweight was 924 g. Recordings were performed at a median gestational age of 30 weeks and a median postnatal age of 10 days. Median weight at study entry was 1111 g. Cerebral oxygenation was not significantly different in infants transitioning from nCPAP to HFNC (66% vs 66%).

CONCLUSION

No difference in cerebral oxygenation in premature infants transitioning from nCPAP to HFNC was observed. This finding is reassuring and further supports the use of HFNC in preterm infants.

Adjustment of high flow nasal cannula rates using real-time work of breathing indices in premature infants with respiratory insufficiency

OBJECTIVE

To assess the feasibility of real-time monitoring of work of breathing (WOB) indices and the impact of adjusting HFNC flow on breathing synchrony and oxygen stability in premature infants.

STUDY DESIGN

A prospective, observational study of infants stable on HFNC. The flow adjusted per predetermined algorithm. Respiratory inductive plethysmography (RIP) noninvasively measured WOB. A high-resolution pulse oximeter collected oxygen saturation and heart rate data. Summary statistics and mixed linear models were used.

RESULTS

Baseline data for 32 infants, final analysis of 21 infants. Eighty-one percent with abnormal WOB. Sixty-two percent demonstrated 20% improvement in WOB. For infants with gestational age <28 weeks, an incremental increase in HFNC flow rate decreased WOB (p < 0.001) and improved oxygen saturation and stability (p < 0.01).

CONCLUSIONS

Premature infants do not receive optimal support on HFNC. The use of a real-time feedback system to adjust HFNC is feasible and improves WOB, oxygen saturation, and oxygen stability. This technology may improve the utility of HFNC in premature infants.

Stabilisation of the preterm infant in the delivery room using nasal high flow: A 5-year retrospective analysis

AIM

This study reviews clinical outcomes after initiating a routine policy of preterm respiratory stabilisation using nasal high flow (HF) in the delivery room (DR).

METHOD

This was a retrospective observational cohort study in a single-centre neonatal intensive care unit and included all neonates born before 32 weeks of gestation between 1 April 2015 and 31 March 2020. Stabilisation measures and outcomes were recorded including oxygen requirements, admission temperature, surfactant administration, invasive ventilation within 72 h of birth, bronchopulmonary dysplasia (BPD) and death.

RESULTS

There were 491 eligible babies during the 5-year epoch. 292 were stabilised using HF in the DR. The median admission temperature in babies transferred on HF was 36.8°C, and the median FiO₂ at admission was 25%. 45% of these infants received surfactant. At 72 postnatal hours, 78% were either sustained on HF or were either self-ventilating in air (SVIA) or receiving low-flow nasal cannula (LFNC) respiratory support. 27% were intubated within 7 days. At 36 weeks postmenstrual age, 36% of survivors had BPD.

CONCLUSION

We have demonstrated that preterm babies <32 weeks can be effectively stabilised on HF in the DR.

Effect of the measurement of the work of breathing on the respiratory outcome of preterms

RATIONALE

There are no validated criteria for the choice of the optimal type of noninvasive respiratory support (NRS) and most appropriate settings in preterms.

METHODS

The work of breathing (WOB) during oxygen (O2) alone, nasal continuous positive pressure (nCPAP) and high flow nasal cannula (HFNC) was compared in preterm babies (23-30 weeks' gestation, "physiological group") needing any type of noninvasive respiratory support ("baseline" NRS) at 4 weeks of life. Babies were thereafter treated with the NRS associated with the greatest reduction in WOB ("optimal NRS"). The respiratory outcome at 36 weeks" gestation of these babies was compared to a "control" group treated with NRS based on standard noninvasive parameters. Preterm babies were prospectively enrolled in 3 centers and randomized into the "physiological" or "control" group.

RESULTS

Thirty babies were randomized. WOB with "baseline" NRS was higher than the "optimal" NRS and the consequent NRS chosen by physicians (p = 0.001). WOB was lower during HFNC than during O2 (p = 0.032) but WOB was comparable between nCPAP and HFNC, and between nCPAP and O2. Notably, WOB was near to normal during spontaneous breathing with O2. Respiratory outcome at 36 week' gestation was comparable between the 2 groups.

CONCLUSION

The optimization of NRS by means of the measurement of WOB in preterms requiring any type of NRS at 4 weeks of life was able to decrease the WOB but had no effect on the clinical outcome at 36 weeks' gestation.

Rates of Bronchopulmonary Dysplasia Following Implementation of a Novel Prevention Bundle

IMPORTANCE

Bronchopulmonary dysplasia (BPD) rates in the United States remain high and have changed little in the last decade.

OBJECTIVE

To develop a consistent BPD prevention bundle in a systematic approach to decrease BPD.

DESIGN, SETTING, AND PARTICIPANTS

This quality improvement study included 484 infants with birth weights from 501 to 1500 g admitted to a level 3 neonatal intensive care unit in the Kaiser Permanente Southern California system from 2009 through 2019. The study period was divided into 3 periods: 1, baseline (2009); 2, initial changes based on ongoing cycles of Plan-Do-Study-Act (2010-2014); and 3, full implementation of successive Plan-Do-Study-Act results (2015-2019).

INTERVENTIONS

A BPD prevention system of care bundle evolved with a shared mental model that BPD is avoidable.

MAIN OUTCOMES AND MEASURES

The primary outcome was BPD in infants with less than 33 weeks' gestational age (hereafter referred to as BPD <33). Other measures included adjusted BPD <33, BPD severity grade, and adjusted median postmenstrual age (PMA) at hospital discharge. Balancing measures were adjusted mortality and adjusted mortality or specified morbidities.

RESULTS

The study population included 484 infants with a mean (SD) birth weight of 1070 (277) g; a mean (SD) gestational age of 28.6 (2.9) weeks; 252 female infants (52.1%); and 61 Black infants (12.6%). During the 3 study periods, BPD <33 decreased from 9 of 29 patients (31.0%) to 3 of 184 patients (1.6%) (P < .001 for trend); special cause variation was observed. The standardized morbidity ratio for the adjusted BPD <33 decreased from 1.2 (95% CI, 0.7-1.9) in 2009 to 0.4 (95% CI, 0.2-0.8) in 2019. The rates of combined grades 1, 2, and 3 BPD decreased from 7 of 29 patients (24.1%) to 17 of 183 patients (9.3%) (P < .008 for trend). Grade 2 BPD rates decreased from 3 of 29 patients (10.3%) to 5 of 183 patients (2.7%) (P = .02 for trend). Adjusted median PMA at home discharge decreased by 2 weeks, from 38.2 (95% CI, 37.3-39.1) weeks in 2009 to 36.8 (95% CI, 36.6-37.1) weeks during the last 3 years (2017-2019) of the full implementation period. Adjusted mortality was unchanged, whereas adjusted mortality or specified morbidities decreased significantly.

CONCLUSIONS AND RELEVANCE

A sustained low rate of BPD was observed in infants after the implementation of a detailed BPD system of care.