Nasal continuous positive airway pressure (NCPAP) or noninvasive neurally adjusted ventilatory assist (NIV-NAVA) for preterm infants with respiratory distress after birth: A randomized controlled trial

Noninvasive neurally-adjusted ventilatory assist in preterm infants: a systematic review and meta-analysis

BACKGROUND

Noninvasive neurally-adjusted ventilatory assist (NIV-NAVA) improves patient-ventilator synchrony and may reduce treatment failure in preterm infants compared with nasal continuous positive airway pressure (NCPAP) and noninvasive positive-pressure ventilation (NIPPV). We conducted a systematic review and meta-analysis to assess the effects of NIV-NAVA in preterm infants with respiratory distress.

METHODS

Four investigators independently assessed the eligibility of studies in CENTRAL, CINAHL, ClinicalTrials.gov, Embase, MEDLINE, PubMed, and WHO ICTRP databases, and extracted data. The included studies were randomized controlled trials (RCTs) comparing NIV-NAVA with other noninvasive ventilation modalities in preterm infants. The certainty of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation approach. The objective of the meta-analysis was to compare NIV-NAVA vs CPAP/NIPPV as a primary mode post extubation.

RESULTS

Five RCTs which examined 279 preterm infants were included. In the subgroup of post-extubation respiratory support, NIV-NAVA decreased treatment failure compared with NCPAP/NIPPV (risk ratio 0.29; 95% confidence interval [0.10, 0.81], 2 RCTs, 96 infants, low certainty of the evidence). NIV-NAVA did not significantly reduce the risk of treatment failure in the subgroup of primary respiratory support (very low certainty of the evidence). There were no significant differences in secondary outcomes with low to very low certainty of evidence.

CONCLUSIONS

In a small cohort with low certainty of evidence, NIV-NAVA may prevent reintubation in preterm infants. Further large-scale RCTs are needed to determine the effects and safety of NIV-NAVA in preterm infants.

Temporal Dynamics of Oxidative Stress and Inflammation in Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is the most common lung complication of prematurity. Despite extensive research, our understanding of its pathophysiology remains limited, as reflected by the stable prevalence of BPD. Prematurity is the primary risk factor for BPD, with oxidative stress (OS) and inflammation playing significant roles and being closely linked to premature birth. Understanding the interplay and temporal relationship between OS and inflammation is crucial for developing new treatments for BPD. Animal studies suggest that OS and inflammation can exacerbate each other. Clinical trials focusing solely on antioxidants or anti-inflammatory therapies have been unsuccessful. In contrast, vitamin A and caffeine, with antioxidant and anti-inflammatory properties, have shown some efficacy, reducing BPD by about 10%. However, more than one-third of very preterm infants still suffer from BPD. New therapeutic agents are needed. A novel tripeptide, N-acetyl-lysyltyrosylcysteine amide (KYC), is a reversible myeloperoxidase inhibitor and a systems pharmacology agent. It reduces BPD severity by inhibiting MPO, enhancing antioxidative proteins, and alleviating endoplasmic reticulum stress and cellular senescence in a hyperoxia rat model. KYC represents a promising new approach to BPD treatment.

Non-invasive neurally adjusted ventilatory assist (NIV-NAVA) reduces extubation failures in preterm neonates-A systematic review and meta-analysis

AIM

To analyse the evidence of non-invasive neurally adjusted ventilatory assist (NIV-NAVA) in preterm neonates compared to nasal continuous positive airway pressure (nCPAP) or nasal intermittent positive pressure ventilation (NIPPV).

METHODS

We performed a systematic review and meta-analysis of randomised controlled trials and included studies where NIV-NAVA was analysed in preterm (<37 gestational weeks) born neonates. Our main outcomes were the need for endotracheal intubation, the need for surfactant therapy, and reintubation rates. Risk ratios (RRs) with 95% confidence intervals (CIs) were calculated.

RESULTS

A total of five studies were included. The endotracheal intubation rate was 25% in the NIV-NAVA group and 26% in the nCPAP group (RR 0.91, CI: 0.56-1.48). The respective rates for surfactant therapy were 30% and 35% (RR 0.85, CI: 0.56-1.29). The reintubation rate in neonates previously invasively ventilated was 8% in the NIV-NAVA group and 29% in the nCPAP/NIPPV group (RR 0.29, 95%CI: 0.10-0.81). Evidence certainty was rated as low for all outcomes.

CONCLUSIONS

NIV-NAVA as the primary respiratory support did not reduce the need for endotracheal intubation or surfactant therapy. NIV-NAVA seemed to reduce the reintubation rate after extubation in pre-term neonates.

NIV-NAVA versus non-invasive respiratory support in preterm neonates: a meta-analysis of randomized controlled trials

OBJECTIVE

To analyze the clinical and physiological outcomes of NIV-NAVA in preterm infants compared with other non-invasive respiratory support.

STUDY DESIGN

We conducted a meta-analysis of RCTs and randomized crossover studies comparing NIV-NAVA to other non-invasive strategies in preterm neonates.

RESULTS

NIV-NAVA was superior to other non-invasive support in maximum EAdi (MD - 0.66 µV; 95% CI - 1.17 to -0.15; p = 0.01), asynchrony index (MD - 49.8%; 95% CI - 63.1 to -36.5; p < 0.01), and peak inspiratory pressure (MD - 2.2 cmH2O; 95% CI - 2.7 to -1.7; p < 0.01). However, there were no significant differences in the incidences of intubation (RR 0.91; 95% CI 0.56-1.48; p = 0.71), reintubation (RR 0.72; 95% CI 0.45-1.16; p = 0.18), or bronchopulmonary dysplasia (RR 0.77; 95% CI 0.37-1.60; p = 0.48).

CONCLUSION

NIV-NAVA was associated with improvements in maximum Edi, asynchrony index, and peak inspiratory pressure relative to other non-invasive respiratory strategies, without significant differences in clinical outcomes between groups.

Novel forms of ventilation in neonates: Neurally adjusted ventilatory assist and proportional assist ventilation

Patient-triggered modes of ventilation are currently the standard of practice in the care of term and preterm infants. Maintaining spontaneous breathing during mechanical ventilation promotes earlier weaning and possibly reduces ventilator-induced diaphragmatic dysfunction. A further development of assisted ventilation provides support in proportion to the respiratory effort and enables the patient to have full control of their ventilatory cycle. In this paper we will review the literature on two of these modes of ventilation: neurally adjusted ventilatory assist (NAVA) and proportional assist ventilation (PAV), propose future studies and suggest clinical applications of these modes.

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.

Diaphragmatic electromyography in infants: an overview of possible clinical applications

Preterm infants often experience breathing instability and a hampered lung function. Therefore, these infants receive cardiorespiratory monitoring and respiratory support. However, the current respiratory monitoring technique may be unreliable for especially obstructive apnea detection and classification and it does not provide insight in breathing effort. The latter makes the selection of the adequate mode and level of respiratory support difficult. Electromyography of the diaphragm (dEMG) has the potential of monitoring heart rate (HR) and respiratory rate (RR), and it provides additional information on breathing effort. This review summarizes the available evidence on the clinical potential of dEMG to provide cardiorespiratory monitoring, to synchronize patient-ventilator interaction, and to optimize the mode and level of respiratory support in the individual newborn infant. We also try to identify gaps in knowledge and future developments needed to ensure widespread implementation in clinical practice. IMPACT: Preterm infants require cardiorespiratory monitoring and respiratory support due to breathing instability and a hampered lung function. The current respiratory monitoring technique may provide unreliable measurements and does not provide insight in breathing effort, which makes the selection of the optimal respiratory support settings difficult. Measuring diaphragm activity could improve cardiorespiratory monitoring by providing insight in breathing effort and could potentially have an important role in individualizing respiratory support in newborn infants.

Noninvasive Neurally Adjusted Ventilation versus Nasal Continuous or Intermittent Positive Airway Pressure for Preterm Infants: A Systematic Review and Meta-Analysis

The noninvasive neurally adjusted ventilatory assist (NIV-NAVA) is a newly developed noninvasive ventilation technique with promising clinical and ventilatory outcomes for preterm infants. This systematic review and meta-analysis aimed to investigate whether NIV-NAVA has better clinical and ventilatory outcomes than nasal continuous airway pressure (NCPAP) or noninvasive positive pressure ventilation (NIPP) on premature infants. MEDLINE, Embase, and CENTRAL were searched, and randomized controlled trials (RCTs) that compared NIV-NAVA with NCPAP or NIPP for preterm infants (gestational age: <37 weeks) were included. We evaluated the following outcomes in the neonatal intensive care unit: the desaturation rate, failure of noninvasive modality requiring intubation when received as the primary mode or the need for re-intubation after extubation from mechanical ventilation in the secondary mode (weaning), length of stay, and fraction of inspired oxygen. The mean difference and risk ratio were used to represent continuous and dichotomous outcomes, respectively. We included nine RCTs involving 339 preterm infants overall. NIV-NAVA showed similar clinical and ventilatory outcomes to NCPAP or NIPP, except for the maximum diaphragmatic electrical activity. The rate of failure of the noninvasive modality was not statistically different between NIV-NAVA and NCPAP. The pooled estimates for the maximum electrical activity were significantly reduced in NIV-NAVA compared with those in NIPP. The findings suggest that NIV-NAVA may be as safe and effective as NCPAP and NIPP for preterm neonates, particularly those who may not tolerate these alternative noninvasive methods. However, further trials are recommended for greater evidence.

Evaluation of NAVA-PAP in premature neonates with apnea of prematurity: minimal backup ventilation and clinically significant events

Background

Neonates with apnea of prematurity (AOP) clinically deteriorate because continuous positive airway pressure (CPAP) provides inadequate support during apnea. Neurally adjusted ventilatory assist (NAVA) provides proportional ventilator support from the electrical activity of the diaphragm. When the NAVA level is 0 cmH2O/mcV (NAVA-PAP), patients receive CPAP when breathing and backup ventilation when apneic. This study evaluates NAVA-PAP and time spent in backup ventilation.

Methods

This was a prospective, two-center, observational study of preterm neonates on NAVA-PAP for AOP. Ventilator data were downloaded after 24 h. The number of clinically significant events (CSEs) was collected. A paired t-test was used to perform statistical analysis.

Results

The study was conducted on 28 patients with a gestational age of 25 ± 1.8 weeks and a study age of 28 ± 23 days. The number of CSEs was 4 ± 4.39/24 h. The patients were on NAVA-PAP for approximately 90%/min, switched to backup mode 2.5 ± 1.1 times/min, and spent 10.6 ± 7.2% in backup.

Conclusion

Preterm neonates on NAVA-PAP had few CSEs with minimal time in backup ventilation.

Invasive and non-invasive ventilatory strategies for early and evolving bronchopulmonary dysplasia

In the age of surfactant and antenatal steroids, neonatal care has improved outcomes of preterm infants dramatically. Since the early 2000's neonatologists have strived to decrease bronchopulmonary dysplasia (BPD) by decreasing ventilator-associated lung injury and utilizing many novel modes of non-invasive respiratory support. After the initial success with nasal continuous positive airway pressure, it was established that discontinuing invasive ventilation early in favor of non-invasive respiratory support is the most effective way to reduce the incidence of BPD. In this review, we discuss the management of the preterm lung from the time of delivery, through the phases of respiratory distress syndrome (early BPD) and then evolving BPD. The goal remains to optimize respiratory support of the preterm lung while minimizing ventilator-associated lung injury and oxygen toxicity. A multidisciplinary approach involving the medical team and family is quintessential in reaching this goal and involves adequate respiratory support, optimizing nutrition and fluid balance as well as preventing infections.

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.

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.

NIV-NAVA versus NCPAP immediately after birth in premature infants: A randomized controlled trial

OBJECTIVE

To evaluate whether noninvasive-neurally adjusted ventilatory assist (NIV-NAVA) decrease respiratory efforts compared to nasal continuous positive airway pressure (NCPAP) during the first hours of life.

METHODS

Twenty infants born between 28⁺⁰ and 31⁺⁶ weeks were randomized to NIV-NAVA or NCPAP. Positive end-expiratory pressure was constantly kept at 6 cmH₂O for both groups and the NAVA level was 1.0 cmH₂O/µV for NIV-NAVA group. The electrical activity of diaphragm (Edi) were recorded for the first two hours.

RESULTS

Peak and minimum Edi decreased similarly in both groups (P = 0.98 and P = 0.59, respectively). Leakages were higher in the NIV-NAVA group than in the NCPAP group (P < 0.001). The neural apnea defined as a flat Edi for ≥ 5 s were less frequent in NIV-NAVA group than in NCPAP group (P = 0.046).

CONCLUSIONS

Immediately applied NIV-NAVA in premature infants did not reduce breathing effort, measured as peak Edi. However, NIV-NAVA decreased neural apneic episodes compared to NCPAP.

Novel Ventilation Strategies to Reduce Adverse Pulmonary Outcomes

Extremely preterm infants who must suddenly support their own gas exchange with lungs that are incompletely developed and lacking adequate amount of surfactant and antioxidant defenses are susceptible to lung injury. The decades-long quest to prevent bronchopulmonary dysplasia has had limited success, in part because of increasing survival of more immature infants. The process must begin in the delivery room with gentle assistance in establishing and maintaining adequate lung aeration, followed by noninvasive support and less invasive surfactant administration. Various modalities of invasive and noninvasive support have been used with varying degree of effect and are reviewed in this article.

Neurally Adjusted Ventilatory Assist in Newborns

Patient-ventilator asynchrony is very common in newborns. Achieving synchrony is quite challenging because of small tidal volumes, high respiratory rates, and the presence of leaks. Leaks also cause unreliable monitoring of respiratory metrics. In addition, ventilator adjustment must take into account that infants have strong vagal reflexes and demonstrate central apnea and periodic breathing, with a high variability in breathing pattern. Neurally adjusted ventilatory assist (NAVA) is a mode of ventilation whereby the timing and amount of ventilatory assist is controlled by the patient's own neural respiratory drive. As NAVA uses the diaphragm electrical activity (Edi) as the controller signal, it is possible to deliver synchronized assist, both invasively and noninvasively (NIV-NAVA), to follow the variability in breathing pattern, and to monitor patient respiratory drive, independent of leaks. This article provides an updated review of the physiology and the scientific literature pertaining to the use of NAVA in children (neonatal and pediatric age groups). Both the invasive NAVA and NIV-NAVA publications since 2016 are summarized, as well as the use of Edi monitoring. Overall, the use of NAVA and Edi monitoring is feasible and safe. Compared with conventional ventilation, NAVA improves patient-ventilator interaction, provides lower peak inspiratory pressure, and lowers oxygen requirements. Evidence from several studies suggests improved comfort, less sedation requirements, less apnea, and some trends toward reduced length of stay and more successful extubation.

Synchronized Nasal Intermittent Positive Pressure Ventilation

Avoiding MV is a critical goal in neonatal respiratory care. Different modes of noninvasive respiratory support beyond nasal CPAP, such as nasal intermittent positive pressure ventilation (NIPPV) and synchronized NIPPV (SNIPPV), may further reduce intubation rates. SNIPPV offers consistent benefits over nonsynchronized techniques such as a more efficient positive pressure transmission to the lung, an effective increase in transpulmonary pressure during ventilation, and a better stabilization of the chest wall during inspiration. This review discusses mechanisms of action, benefits and limitations of synchronized noninvasive ventilation, describes the different modes of synchronization, and analyzes properties and clinical results.

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.

Proportional assist and neurally adjusted ventilation: Clinical knowledge and future trials in newborn infants

Different types of patient triggered ventilator modes have become the mainstay of ventilation in term and preterm newborn infants. Maintaining spontaneous breathing has allowed for earlier weaning and the additive effects of respiratory efforts combined with pre-set mechanical inflations have reduced mean airway pressures, both of which are important components in trying to avoid lung injury and promote normal lung development. New sophisticated modes of assisted ventilation have been developed during the last decades where the control of ventilator support is turned over to the patient. The ventilator detects the respiratory effort and adjusts ventilatory assistance proportionally to each phase of the respiratory cycle, thus enabling the patient to have full control of the start, the duration and the amount of ventilatory assistance. In this paper we will review the literature on the ventilatory modes of proportional assist ventilation and neurally adjusted ventilatory assistance, examine the different ways the signals are analyzed, propose future studies, and suggest ways to apply these modes in the clinical environment.

Bayesian network meta-analysis of the efficacy of 22 ventilation strategies in premature infants with respiratory distress syndrome

Introduction: Respiratory Distress Syndrome (RDS) is a common lung disease in the neonatal period. The infants are mostly premature, with a high mortality rate and many complications. Currently, respiratory support therapy is still one of the primary treatment measures for RDS in preterm infants. There are 22 modes of ventilation currently in use.Areas covered: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, EMBASE, MEDLINE, CINAHL, and Web of Science by using a combination of Medical Subject Headings (MeSH) and text words. The search time limit is set from the establishment of the above-mentioned databases to August 2020.Expert opinion: In total, 37 randomized controlled trials were included for the network meta-analysis, which consisted of 5,101 patients who received one of 22 ventilation modes. The results of the network meta-analysis showed that the Volume-Control (by adjusting tidal volume) ventilation mode is the most successful in reducing the mortality of preterm infants with RDS, followed by Synchronized Intermittent Mechanical Ventilation and Volume Guaranteed Ventilation. This network meta-analysis highlights the variability in techniques within treatment of acute respiratory distress syndrome in premature infants and compares different ventilation strategies. This study is registered with PROSPERO, number CRD42020213050.Conclusion: This network meta-analysis highlights the variability in techniques within treatment of acute respiratory distress syndrome in premature infants and compares different ventilation strategies. Future studies need to be rigorous in design and delivery and include comprehensive descriptions of all aspects of methodology to further enable appraisal and interpretation of results. This study is registered with PROSPERO, number CRD42020213050.

Novel predictor markers for early differentiation between transient tachypnea of newborn and respiratory distress syndrome in neonates

Neonatal Respiratory Distress Syndrome (RDS) and Transient Tachypnea of newborn (TTN) are common similar neonatal respiratory diseases. Study the early predictor markers in differentiation between TTN and RDS in neonates. A prospective case control study which was done in Neonatal Intensive Care Unit (NICU) of Tanta University Hospital (TUH) from September 2016 to March 2018. Three groups of neonates were included in the study: RDS group (45 neonates), TTN group (45 neonates), and control group (45 healthy neonates). There were statistically significant difference (SSD) between our studied three groups as regard serum Malondialdehyde (MDA), Superoxide dismutase SOD, Lactate dehydrogenase (LDH), and blood PH and P-values were 0.001* for these comparative parameters. The ROC curve of RDS cases revealed that the serum MDA Cut off, sensitivity and specificity were 1.87 mmol/L, 98%, 96%, respectively which had the highest sensitivity and specificity followed by the serum SOD then the serum LDH and lastly the blood PH while in TTN cases, the serum MDA Cut off, sensitivity and specificity were 0.74 mmol/L, 96%, 93%, respectively then the serum SOD then the serum LDH and lastly the blood PH. Serum MDA, SOD, LDH, and PH had a beneficial role as early predictors in differentiation between TTN and RDS in neonates.

Non-Invasive Ventilatory Strategies to Decrease Bronchopulmonary Dysplasia-Where Are We in 2021?

Recent advances in neonatology have led to the increased survival of extremely low-birth weight infants. However, the incidence of bronchopulmonary dysplasia (BPD) has not improved proportionally, partly due to increased survival of extremely premature infants born at the late-canalicular stage of lung development. Due to minimal surfactant production at this stage, these infants are at risk for severe respiratory distress syndrome, needing prolonged ventilation. While the etiology of BPD is multifactorial with antenatal, postnatal, and genetic factors playing a role, ventilator-induced lung injury is a major, potentially modifiable, risk factor implicated in its causation. Infants with BPD are at a higher risk of developing complications including sepsis, pulmonary arterial hypertension, respiratory failure, and death. Long-term problems include increased risk of hospital readmissions, respiratory infections, and asthma-like symptoms during infancy and childhood. Survivors who have BPD are also at increased risk of poor neurodevelopmental outcomes. While the ultimate solution for avoiding BPD lies in the prevention of preterm births, strategies to decrease its incidence are the need of the hour. It is time to focus on gentler modes of ventilation and the use of less invasive surfactant administration techniques to mitigate lung injury, thereby potentially decreasing the burden of BPD. In this article, we discuss the use of non-invasive ventilation in premature infants, with an emphasis on studies showing an effect on BPD with different modes of non-invasive ventilation. Practical considerations in the use of nasal intermittent positive pressure ventilation are also discussed, considering the significant heterogeneity in clinical practices and management strategies in its use.

ATS Core Curriculum 2020. Pediatric Pulmonary Medicine

The American Thoracic Society Core Curriculum updates clinicians annually in adult and pediatric pulmonary disease, medical critical care, and sleep medicine, in a 3- to 4-year recurring cycle of topics. These topics will be presented at the 2020 International Conference. Below is the pediatric pulmonary medicine core, including pediatric hypoxemic respiratory failure; modalities in noninvasive management of chronic respiratory failure in childhood; surgical and nonsurgical management of congenital lung malformations; an update on smoke inhalation lung injury; an update on vaporizers, e-cigarettes, and other electronic delivery systems; pulmonary complications of sarcoidosis; pulmonary complications of congenital heart disease; and updates on the management of congenital diaphragmatic hernia.

Continuous neurally adjusted ventilation: a feasibility study in preterm infants

OBJECTIVES

To assess the feasibility and tolerance of NeuroPAP, a new non-invasive ventilation mode which continuously adjusts (during both inspiration and expiration) the pressure support proportionally to the diaphragm electrical activity (Edi), in preterm infants and to evaluate the impact on ventilation pressure and Edi.

DESIGN

Prospective cross-over single-centre feasibility study.

SETTING

One level 3 neonatal intensive care unit in Canada.

PATIENTS

Stable preterm infants ventilated with non-invasive positive pressure ventilation (NIPPV).

INTERVENTIONS

Subjects were successively ventilated in NIPPV with prestudy settings (30 min), in NeuroPAP with minimal pressure similar to NIPPV PEEP (positive end-expiratory pressure) (60 min), in NeuroPAP with minimal pressure reduced by 2 cmH₂0 (60 min), in continuous positive airway pressure (15 min) and again in NIPPV (30 min). Main outcome measures included tolerance, ventilation pressure, Edi and patient-ventilator synchrony.

RESULTS

Twenty infants born at 28.0±1.0 weeks were included. NeuroPAP was well tolerated and could be delivered during 100% of planned period. During NeuroPAP, the PEEP was continuously adjusted proportionally to tonic diaphragm Edi, although the average PEEP value was similar to the set minimal pressure. During NeuroPAP, 83 (78-86)% breaths were well synchronised vs 9 (6-12)% breaths during NIPPV (p<0.001).

CONCLUSIONS

NeuroPAP is feasible and well tolerated in stable preterm infants, and it allows transient adaptation in PEEP in response to tonic diaphragm electrical activity changes. Further studies are warranted to determine the impact of these findings on clinical outcomes.

TRIAL REGISTRATION NUMBER

NCT02480205.

Practical aspects on the use of non-invasive respiratory support in preterm infants

Preterm infants frequently present with respiratory insufficiency requiring respiratory assistance. Invasive mechanical ventilation has been associated with several short and long term complications. Therefore, the practice of early use of non-invasive ventilation has been adopted. Nasal CPAP proved efficacy as an initial therapy for preterm infants. Non-invasive positive pressure ventilation is an alternative used to mitigate CPAP failure in infants with apnea or increased work of breathing. High flow nasal cannula gained popularity primarily due to the ease of its use, despite multiple prominent trials that demonstrated its inferiority. Bi-level positive airway pressure and neurally adjusted non-invasive ventilatory are used in infants with apnea and increased work of breathing. The effectiveness of non invasive ventilation tools can be augmented by having a proper protocol for initiation, weaning, skin care, positioning, and developmental care during their application.

A Review on Non-invasive Respiratory Support for Management of Respiratory Distress in Extremely Preterm Infants

Majority of extremely preterm infants require positive pressure ventilatory support at the time of delivery or during the transitional period. Most of these infants present with respiratory distress (RD) and continue to require significant respiratory support in the neonatal intensive care unit (NICU). Bronchopulmonary dysplasia (BPD) remains as one of the major morbidities among survivors of the extremely preterm infants. BPD is associated with long-term adverse pulmonary and neurological outcomes. Invasive mechanical ventilation (IMV) and supplemental oxygen are two major risk factors for the development of BPD. Non-invasive ventilation (NIV) has been shown to decrease the need for IMV and reduce the risk of BPD when compared to IMV. This article reviews respiratory management with current NIV support strategies in extremely preterm infants both in delivery room as well as in the NICU and discusses the evidence to support commonly used NIV modes including nasal continuous positive airway pressure (NCPAP), nasal intermittent positive pressure ventilation (NIPPV), bi-level positive pressure (BI-PAP), high flow nasal cannula (HFNC), and newer NIV strategies currently being studied including, nasal high frequency ventilation (NHFV) and non-invasive neutrally adjusted ventilatory assist (NIV-NAVA). Randomized, clinical trials have shown that early NIPPV is superior to NCPAP to decrease the need for intubation and IMV in preterm infants with RD. It is also important to understand that selection of the device used to deliver NIPPV has a significant impact on its success. Ventilator generated NIPPV results in significantly lower rates of extubation failures when compared to Bi-PAP. Future studies should address synchronized NIPPV including NIV-NAVA and early rescue use of NHFV in the respiratory management of extremely preterm infants.