Efficacy of a new technique - INtubate-RECruit-SURfactant-Extubate - "IN-REC-SUR-E" - in preterm neonates with respiratory distress syndrome: study protocol for a randomized controlled trial

The long-term outcomes of preterm infants receiving non-invasive high-frequency oscillatory ventilation

OBJECTIVE

To investigate the clinical outcomes of preterm infants who received non-invasive high-frequency oscillatory ventilation following extubation in a neonatal intensive care unit.

METHODS

Infants born between 25 and 34 weeks of gestation with a birth weight of <1,500 g, who were admitted into the neonatal intensive care unit of Guangxi Maternal and Child Health Hospital, Nanning, Guangxi, China, requiring mechanical ventilation on admission were randomized to the non-invasive high-frequency ventilation group, nasal intermittent positive pressure ventilation group, or nasal continuous positive airway pressure group following extubation. Their respiratory and neurodevelopmental outcomes were assessed at 12 and 24 months of corrected age.

RESULTS

Among 149 preterm infants who underwent randomization, 139 completed their treatment in the neonatal intensive care unit (45, 47, 47 in the non-invasive high-frequency ventilation group, nasal intermittent positive pressure ventilation group, or nasal continuous positive airway pressure group, respectively), 113 were assessed at 12-month corrected age, and 110 of 113 were assessed again at 24-month corrected age. There were no differences in the number of times bronchitis, pneumonia, wheezing episodes, and re-hospitalization rates appeared due to respiratory diseases among the three groups (P > 0.05); the pulmonary function tests at 12-month corrected age showed respiratory rate, tidal volume, inspiratory time/expiratory time, time to peak expiratory flow/expiratory time, volume at peak expiratory flow/expiratory volume, expiratory flow at 25, 50, and 75% tidal volume were all similar among infants from the 3 groups (P > 0.05). There were no differences in the rates of neurodevelopmental impairment among the three groups at 24-month corrected age (P > 0.05).

CONCLUSION

As post-extubation respiratory support in preterm infants, non-invasive high-frequency ventilation did not increase the rates of long-term respiratory morbidities and neurodevelopmental impairment compared with nasal intermittent positive pressure ventilation and nasal continuous positive airway pressure.

An Update on the Prevention and Management of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a common morbidity affecting preterm infants and is associated with substantial long-term disabilities. There has been no change in the incidence of BPD over the past 20 years, despite improvements in survival and other outcomes. The preterm lung is vulnerable to injuries occurring as a result of invasive ventilation, hyperoxia, and infections that contribute to the development of BPD. Clinicians caring for infants in the neonatal intensive care unit use multiple therapies for the prevention and management of BPD. Non-invasive ventilation strategies and surfactant administration via thin catheters are treatment approaches that aim to avoid volutrauma and barotrauma to the preterm developing lung. Identifying high-risk infants to receive postnatal corticosteroids and undergo patent ductus arteriosus closure may help to individualize care and promote improved lung outcomes. In infants with established BPD, outpatient management is complex and requires coordination from several specialists and therapists. However, most current therapies used to prevent and manage BPD lack solid evidence to support their effectiveness. Further research is needed with appropriately defined outcomes to develop effective therapies and impact the incidence of BPD.

Outcome of Very Premature Newborn Receiving an Early Second Dose of Surfactant for Persistent Respiratory Distress Syndrome

Background: Infants presenting respiratory distress syndrome (RDS) not responding to surfactant often receive a second instillation. Few studies evaluated the consequences of this second administration. This study aimed at determining the outcome of infants presenting persistent RDS and receiving an early second dose of surfactant. Methods: Infants below 32 weeks' gestation who received a second dose of 100mg/kg of surfactant within the first 72 h of life, were retrospectively involved in this 42 months' study. They were matched to two controls receiving a single dose of 200mg/Kg based upon gender and gestational age. Results: 52/156 infants receiving two doses (Group 2-doses) were significantly more often SGA [22 (42%) vs. 21 (20%) p = 0.04] and outborn [29 (56%) vs. 13 (12%) p = 0.001]. They had received antenatal corticos teroid therapy less often [26 (50%) vs. 89 (86%) p = 0.001] and presented more severe RDS based upon FiO2 level, oxygenation index and radiography. Group 2-doses survival was lower (65.4% vs. 79.6 % p < 0.1) but surviving infants did not have different morbidity than controls. Discussion: Premature newborn receiving a second dose of surfactant had adverse antenatal characteristics, presented more severe RDS and only partially responded to the first dose. Outcomes of surviving infants who received 2 doses of surfactant were comparable to others.

Aerosol drug delivery to spontaneously-breathing preterm neonates: lessons learned

Delivery of medications to preterm neonates receiving non-invasive ventilation (NIV) represents one of the most challenging scenarios for aerosol medicine. This challenge is highlighted by the undersized anatomy and the complex (patho)physiological characteristics of the lungs in such infants. Key physiological restraints include low lung volumes, low compliance, and irregular respiratory rates, which significantly reduce lung deposition. Such factors are inherent to premature birth and thus can be regarded to as the intrinsic factors that affect lung deposition. However, there are a number of extrinsic factors that also impact lung deposition: such factors include the choice of aerosol generator and its configuration within the ventilation circuit, the drug formulation, the aerosol particle size distribution, the choice of NIV type, and the patient interface between the delivery system and the patient. Together, these extrinsic factors provide an opportunity to optimize the lung deposition of therapeutic aerosols and, ultimately, the efficacy of the therapy.In this review, we first provide a comprehensive characterization of both the intrinsic and extrinsic factors affecting lung deposition in premature infants, followed by a revision of the clinical attempts to deliver therapeutic aerosols to premature neonates during NIV, which are almost exclusively related to the non-invasive delivery of surfactant aerosols. In this review, we provide clues to the interpretation of existing experimental and clinical data on neonatal aerosol delivery and we also describe a frame of measurable variables and available tools, including in vitro and in vivo models, that should be considered when developing a drug for inhalation in this important but under-served patient population.

Non-invasive high-frequency oscillatory ventilation in preterm infants after extubation: a randomized, controlled trial

OBJECTIVE

To investigate the effectiveness and safety of non-invasive high-frequency oscillatory ventilation (NHFOV) in post-extubation preterm infants.

METHODS

This was a randomized, controlled trial. A total of 149 preterm infants aged between 25 to 34 weeks' gestational age with a birth weight of <1500 g who required invasive mechanical ventilation on admission were included. After extubation, they were randomized to the NHFOV group (n = 47), nasal intermittent positive pressure ventilation (NIPPV) group (n = 51), or nasal continuous positive airway pressure (NCPAP) group (n = 51). We compared the effectiveness and safety among these three groups.

RESULTS

A total of 139 preterm infants finally completed the study. The reintubation rate was significantly lower in the NHFOV group than in the other groups. The duration of non-invasive ventilation and the length of hospital stay in the NHFOV and NIPPV groups were significantly shorter than those in the NCPAP group. The incidence of bronchopulmonary dysplasia in the NHFOV and NIPPV groups was significantly lower than that in the NCPAP group. The NHFOV group had significantly less nasal injury than the NCPAP group.

CONCLUSION

As post-extubation respiratory support in preterm infants, NHFOV has a lower reintubation rate compared with NCPAP and NIPPV, without increasing the rate of complications.

Application of two different nasal CPAP levels for the treatment of respiratory distress syndrome in preterm infants-"The OPTTIMMAL-Trial"-Optimizing PEEP To The IMMAture Lungs: study protocol of a randomized controlled trial

Background

Nasal continuous positive airway pressure (CPAP) applies positive end-expiratory pressure (PEEP) and has been shown to reduce the need for intubation and invasive mechanical ventilation in very low birth weight infants with respiratory distress syndrome. However, CPAP failure rates of 50% are reported in large randomized controlled trials. A possible explanation for these failure rates is the application of insufficient low levels of PEEP during nasal CPAP treatment to maintain adequate functional residual capacity shortly after birth. The optimum PEEP level to treat symptoms of respiratory distress in very low birth weight infants has not been assessed in clinical studies. The aim of the study is to compare two different PEEP levels during nasal CPAP treatment in preterm infants.

Methods

In this randomized multicenter trial, 216 preterm infants born at 26 + 0–29 + 6 gestational weeks will be allocated to receive a higher (6–8 cmH₂O) or a lower (3–5 cmH₂O) PEEP during neonatal resuscitation and the first 120 h of life. The PEEP level within each group will be titrated throughout the intervention based on the FiO₂ (fraction of inspired oxygen concentration) requirements to keep oxygenation within the target range. The primary outcome is defined as the need for intubation and mechanical ventilation for > 1 h or being not ventilated but reaching one of the two pre-defined CPAP failure criteria (FiO₂ > 0.5 for > 1 h or pCO₂ ≥ 70 mmHg in two consecutive blood gas analyses at least 2 h apart).

Discussion

Based on available data from the literature, the optimum level of PEEP that most effectively treats respiratory distress syndrome in preterm infants is unknown, since the majority of large clinical trials applied a wide range of PEEP levels (4–8 cmH₂O). The rationale for our study hypothesis is that the early application of a higher PEEP level will more effectively counteract the collapsing properties of the immature and surfactant-deficient lungs and that the level of inspired oxygen may serve as a surrogate marker to guide PEEP titration. Finding the optimum noninvasive continuous distending pressure during early nasal CPAP is required to improve CPAP efficacy and as a consequence to reduce the exposure to ventilator-induced lung injury and the incidence of chronic lung disease in this vulnerable population of very preterm infants.

Trial registration

drks.de DRKS00019940. Registered on March 13, 2020

Introduction of less invasive surfactant administration (LISA), impact on diagnostic and therapeutic procedures in early life: a historical cohort study

Background

In preterm infants with Respiratory Distress Syndrome (RDS), Less Invasive Surfactant Administration (LISA) has been established to reduce the need of mechanical ventilation and might improve survival rates without bronchopulmonary dysplasia. The aim of this study was to investigate whether NICU care has changed after introduction of less invasive surfactant administration (LISA), with regard to diagnostic and therapeutic procedures in the first week of life.

Methods

Infants with gestational age < 32 weeks who received surfactant by LISA (June 2014 – December 2017, n = 169) were retrospectively compared to infants who received surfactant after intubation (January 2012 – May 2014, n = 155). Local protocols on indication for surfactant, early onset sepsis, blood transfusions and enteral feeding did not change between both study periods. Besides, as secondary outcome complications of prematurity were compared. Data was collected from electronic patient files and compared by univariate analysis through Students T-test, Mann Whitney-U test, Pearson Chi-Square test or Linear by Linear Association.

Results

All baseline characteristics of both groups were comparable. Compared to controls, LISA patients received a higher total surfactant dose (208 vs.160 mg/kg; p < 0.001), required redosing more frequently (32.5% vs. 21.3%; p = 0.023), but needed less mechanical ventilation (35.5% vs. 76.8%; p < 0.001). After LISA, infants underwent fewer X-rays (1.0 vs. 3.0, p < 0.001), blood gas examinations (3.0 vs. 5.0, p < 0.001), less inotropic drugs (9.5% vs. 18.1%; p = 0.024), blood transfusions (24.9% vs. 41.9%, p = 0.003) and had shorter duration of antibiotic therapy for suspected early onset sepsis (3.0 vs. 5.0 days, p < 0.001). Moreover, enteral feeding was advanced faster (120 vs. 100 mL/kg/d, p = 0.048) at day seven. There were no differences in complications of prematurity.

Conclusion

The introduction of LISA is associated with significantly fewer diagnostic and therapeutic procedures in the first week of life, which emphasizes the beneficial effects of LISA.

Lung recruitment before surfactant administration in extremely preterm neonates with respiratory distress syndrome (IN-REC-SUR-E): a randomised, unblinded, controlled trial

BACKGROUND

The importance of lung recruitment before surfactant administration has been shown in animal studies. Well designed trials in preterm infants are absent. We aimed to examine whether the application of a recruitment manoeuvre just before surfactant administration, followed by rapid extubation (intubate-recruit-surfactant-extubate [IN-REC-SUR-E]), decreased the need for mechanical ventilation during the first 72 h of life compared with no recruitment manoeuvre (ie, intubate-surfactant-extubate [IN-SUR-E]).

METHODS

We did a randomised, unblinded, controlled trial in 35 tertiary neonatal intensive care units in Italy. Spontaneously breathing extremely preterm neonates (24 + 0 to 27 + 6 weeks' gestation) reaching failure criteria for continuous positive airway pressure within the first 24 h of life were randomly assigned (1:1) with a minimisation algorithm to IN-REC-SUR-E or IN-SUR-E using an interactive web-based electronic system, stratified by clinical site and gestational age. The primary outcome was the need for mechanical ventilation in the first 72 h of life. Analyses were done in intention-to-treat and per-protocol populations, with a log-binomial regression model correcting for stratification factors to estimate adjusted relative risk (RR). This study is registered with ClinicalTrials.gov, NCT02482766.

FINDINGS

Of 556 infants assessed for eligibility, 218 infants were recruited from Nov 12, 2015, to Sept 23, 2018, and included in the intention-to-treat analysis. The requirement for mechanical ventilation during the first 72 h of life was reduced in the IN-REC-SUR-E group (43 [40%] of 107) compared with the IN-SUR-E group (60 [54%] of 111; adjusted RR 0·75, 95% CI 0·57-0·98; p=0·037), with a number needed to treat of 7·2 (95% CI 3·7-135·0). The addition of the recruitment manoeuvre did not adversely affect the safety outcomes of in-hospital mortality (19 [19%] of 101 in the IN-REC-SUR-E group vs 37 [33%] of 111 in the IN-SUR-E group), pneumothorax (four [4%] of 101 vs seven [6%] of 111), or grade 3 or worse intraventricular haemorrhage (12 [12%] of 101 vs 17 [15%] of 111).

INTERPRETATION

A lung recruitment manoeuvre just before surfactant administration improved the efficacy of surfactant treatment in extremely preterm neonates compared with the standard IN-SUR-E technique, without increasing the risk of adverse neonatal outcomes. The reduced need for mechanical ventilation during the first 72 h of life might facilitate implementation of a non-invasive respiratory support strategy.

FUNDING

None.

Nanotechnology and Early Human Development

The application of nanotechnology, molecular biotechnologies, and nano-sciences for medical purposes has been termed nanomedicine, a promising growing area of medical research. The aim of this paper is to provide an overview of and discuss nanotechnology applications in the early epochs of life, from transplacental transfer to neonatal/pediatric conditions. Diagnostic and therapeutic applications, mainly related to the respiratory tract, the neurosensory system, and infections, are explored and discussed. Preclinical studies show promising results for a variety of conditions, including for the treatment of pregnancy complications and fetal, neonatal, and pediatric diseases. However, given the complexity of the functions and interactions between the placenta and the fetus, and the complex and incompletely understood determinants of tissue growth and differentiation during early life, there is a need for much more data to confirm the safety and efficacy of nanotechnology in this field.

Surfactant, steroids and non-invasive ventilation in the prevention of BPD

Bronchopulmonary dysplasia (BPD) is a complex disorder with multiple factors implicated in its etiopathogenesis. Despite the scientific advances in the field of neonatology, the incidence of BPD has remained somewhat constant due to increased survival of extremely premature infants. Surfactant deficiency in the immature lung, exposure to invasive mechanical ventilation leading to volutrauma, barotrauma and lung inflammation are some of the critical contributing factors to the pathogenesis of BPD. Hence, strategies to prevent BPD in the postnatal period revolve around mitigation of this injury and inflammation. This article reviews the progress made in the last 5 years in the development of new preparations of surfactant, use of corticosteroids and non-invasive ventilation in the prevention of BPD. Emerging techniques of surfactant delivery through minimally invasive and non-invasive routes are also discussed.

Lung Recruitment Strategies During High Frequency Oscillatory Ventilation in Preterm Lambs

Background: High frequency oscillatory ventilation (HFOV) is considered a lung protective ventilation mode in preterm infants only if lung volume is optimized. However, whilst a "high lung volume strategy" is advocated for HFOV in preterm infants this strategy is not precisely defined. It is not known to what extent lung recruitment should be pursued to provide lung protection. In this study we aimed to determine the relationship between the magnitude of lung volume optimization and its effect on gas exchange and lung injury in preterm lambs. Methods: 36 surfactant-deficient 124-127 d lambs commenced HFOV immediately following a sustained inflation at birth and were allocated to either (1) no recruitment (low lung volume; LLV), (2) medium- (MLV), or (3) high lung volume (HLV) recruitment strategy. Gas exchange and lung volume changes over time were measured. Lung injury was analyzed by post mortem pressure-volume curves, alveolar protein leakage, gene expression, and histological injury score. Results: More animals in the LLV developed a pneumothorax compared to both recruitment groups. Gas exchange was superior in both recruitment groups compared to LLV. Total lung capacity tended to be lower in the LLV group. Other parameters of lung injury were not different. Conclusions: Lung recruitment during HFOV optimizes gas exchange but has only modest effects on lung injury in a preterm animal model. In the HLV group aiming at a more extensive lung recruitment gas exchange was better without affecting lung injury.

[Research advances in noninvasive high-frequency oscillatory ventilation in neonates]

Noninvasive ventilation is an important respiratory management technique for the treatment of mild or moderate respiratory failure in the neonatal intensive care unit. Its reasonable application can effectively avoid the use of invasive ventilation and related complications. Recent studies have found that noninvasive high-frequency oscillatory ventilation has the advantages of both nasal continuous positive airway pressure and high-frequency ventilation and can rapidly improve oxygenation, effectively remove carbon dioxide, and improve respiratory failure. Therefore, it is considered a new and effective noninvasive ventilation mode. There are many studies on the rational use, efficacy, and safety of noninvasive high-frequency oscillatory ventilation in neonates around the world. This article reviews the advances in the clinical studies on noninvasive high-frequency oscillatory ventilation in neonates.

[Research advances in noninvasive high-frequency oscillatory ventilation in neonates]

Noninvasive ventilation is an important respiratory management technique for the treatment of mild or moderate respiratory failure in the neonatal intensive care unit. Its reasonable application can effectively avoid the use of invasive ventilation and related complications. Recent studies have found that noninvasive high-frequency oscillatory ventilation has the advantages of both nasal continuous positive airway pressure and high-frequency ventilation and can rapidly improve oxygenation, effectively remove carbon dioxide, and improve respiratory failure. Therefore, it is considered a new and effective noninvasive ventilation mode. There are many studies on the rational use, efficacy, and safety of noninvasive high-frequency oscillatory ventilation in neonates around the world. This article reviews the advances in the clinical studies on noninvasive high-frequency oscillatory ventilation in neonates.

Surfactant for Respiratory Distress Syndrome: New Ideas on a Familiar Drug with Innovative Applications

In the last 4 decades, advances in neonatology have led to a significant increase in the survival of preterm infants. One of the biggest advances was the introduction of surfactant replacement therapy for the treatment of respiratory distress syndrome. This is the main cause of respiratory insufficiency in preterm infants and is one of the major causes of perinatal morbidity and mortality. Surfactant replacement therapy is already a well-investigated and established therapy in neonatology. However, surfactant replacement therapy has progressed and been refined over recent decades, especially with the increasing care for preterm infants born before 26 weeks' gestational age and the recent clinical focus on avoiding mechanical ventilation. Clinical evidence is evolving on new types of surfactant, surfactant dosages, co-medication given before, with, or after surfactant replacement, and new technical advances regarding the mode of administration.

New Insights on Early Patterns of Respiratory Disease among Extremely Low Gestational Age Newborns

BACKGROUND

The analysis of early patterns of lung disease among preterm infants may help to identify predictors of pulmonary deterioration.

OBJECTIVES

To analyze FIO2 requirement in the first 14 days of life among preterm infants and to find predictors of bronchopulmonary dysplasia (BPD).

METHODS

Retrospective cohort study.

SETTING

3 Italian level III NICUs.

POPULATION

infants born between 240/7 and 276/7 weeks' gestational age (GA) who survived to 14 days. A consecutive sample of 588 infants was analyzed. Daily mode FIO2 in the first 2 weeks of life were analyzed according to the criteria defined by Laughon et al. [Pediatrics 2009;123:1124-1131], who found 3 early respiratory patterns: consistently low FIO2 (LowFIO2), pulmonary deterioration (PD), and early persistent pulmonary deterioration (EPPD). Factors associated with pulmonary deterioration were studied by univariate and multivariate analysis.

RESULTS

Forty percent of infants had low FIO2, 18% had pulmonary deterioation, 21% had early persistent pulmonary deterioration, and 21% had a previously unreported pattern (pulmonary improvement, PI). The prevalence of BPD was 7% in the LowFIO2 group, 28% in the PI group, 44% in the PD group, and 62% in the EPPD group (p = 0.000). Infants with lung deterioration were more frequently males (OR = 2.019, CI: 1.319-3.090, p = 0.001), had lower GA (OR = 0.945, CI: 0.915-0.975, p = 0.000), higher incidence of severe respiratory distress syndrome (OR = 2.956, CI: 1.430-6.112, p = 0.003), and lack of postnatal caffeine (OR = 0.167, CI: 0.052-0.541, p = 0.003).

CONCLUSIONS

We report 4 distinct patterns of early respiratory disease associated with significantly different prevalence of BPD and discuss risk factors for lung deterioration.

Noninvasive Ventilation with Heliox for Respiratory Distress Syndrome in Preterm Infant: A Systematic Review and Meta-Analysis

Objectives. To assess whether noninvasive ventilation with Heliox reduces the need for endotracheal ventilation and subsequent complications in preterm infants with respiratory distress syndrome (RDS). Methods. A search of major electronic databases, including MEDLINE and the Cochrane Central Register of Controlled Trials, for randomized or quasi-randomized controlled trials that compared noninvasive ventilation with Heliox versus noninvasive ventilation with standard gas for preterm infants with RDS was performed. The primary outcome was the incidence of intubation. The secondary outcomes were the level of PaCO₂, the use of surfactant, and other complications. Results. Two randomized and one quasi-randomized controlled trials including 123 preterm infants were assessed. Heliox was found to significantly decrease the incidence of intubation (RR: 0.42; 95% CI: 0.23 to 0.78), the level of PaCO₂ (MD: −9.61; 95% CI: −15.76 to −03.45), and the use of surfactant (RR: 0.25; 95% CI: 0.10 to 0.61) as compared with standard gas. No significant differences were found in other secondary outcomes. Conclusions. Noninvasive ventilation with Heliox decreases the incidence of intubation in preterm infants suffering from RDS. However, data on clinical outcomes are limited. Larger trials are needed to verify the beneficial effects.