Review demonstrates that less invasive surfactant administration in preterm neonates leads to fewer complications

NON-pharmacological Approach Less Invasive Surfactant Administration (NONA-LISA) trial: protocol for a randomised controlled trial

INTRODUCTION

Using pre-procedure analgesia with the risk of apnoea may complicate the Less Invasive Surfactant Administration (LISA) procedure or reduce the effect of LISA.

METHODS

The NONA-LISA trial (ClinicalTrials.gov, NCT05609877) is a multicentre, blinded, randomised controlled trial aiming at including 324 infants born before 30 gestational weeks, meeting the criteria for surfactant treatment by LISA. Infants will be randomised to LISA after administration of fentanyl 0.5-1 mcg/kg intravenously (fentanyl group) or isotonic saline solution intravenously (saline group). All infants will receive standardised non-pharmacological comfort care before and during the LISA procedure. Additional analgesics will be provided at the clinician's discretion. The primary outcome is the need for invasive ventilation, meaning mechanical or manual ventilation via an endotracheal tube, for at least 30 min (cumulated) within 24 h of the procedure. Secondary outcomes include the modified COMFORTneo score during the procedure, bronchopulmonary dysplasia at 36 weeks, and mortality at 36 weeks.

DISCUSSION

The NONA-LISA trial has the potential to provide evidence for a standardised approach to relief from discomfort in preterm infants during LISA and to reduce invasive ventilation. The results may affect future clinical practice.

IMPACT

Pre-procedure analgesia is associated with apnoea and may complicate procedures that rely on regular spontaneous breathing, such as Less Invasive Surfactant Administration (LISA). This randomised controlled trial addresses the effect of analgesic premedication in LISA by comparing fentanyl with a placebo (isotonic saline) in infants undergoing the LISA procedure. All infants will receive standardised non-pharmacological comfort. The NONA-LISA trial has the potential to provide evidence for a standardised approach to relief from discomfort or pain in preterm infants during LISA and to reduce invasive ventilation. The results may affect future clinical practice regarding analgesic treatment associated with the LISA procedure.

Less Invasive Surfactant Administration for the Treatment of Neonatal Respiratory Distress Syndrome Combined With Noninvasive Ventilation in Anhui Province, China: A Retrospective Cohort Study

The less invasive surfactant application (LISA) technology has been widely used to manage breathing in premature infants. Premature infants with respiratory distress syndrome (RDS) were retrospectively analyzed and divided into 2 groups according to the drug delivery methods used: LISA versus traditional pulmonary surfactant injection (INSURE). The decrease of transcutaneous saturation (TcSO2) and heart rate during surfactant delivery in the LISA group was higher than that in the INSURE group (P < .05). Between the 2 groups, there was no significant difference in the change in partial pressure of oxygen/fraction of inspired oxygen value before and after drug delivery; second-use pulmonary surfactant; noninvasive ventilation (NIV) failure rate; incidence of some complications; duration of NIV use; hospitalization time; and mortality (P > .05). However, the incidence of bronchopulmonary dysplasia (BPD) in the LISA group was lower than that in the INSURE group (P < .05). The clinical efficacy of LISA combined with the NIV treatment in premature infants with RDS was clear, and this treatment could reduce the incidence of BPD.

Diagnosis and management of neonatal respiratory distress syndrome in Japan: A national survey

BACKGROUND

Respiratory distress syndrome (RDS) is characterized by a lack of lung surfactant; therefore, biochemical evidence of surfactant deficiency is needed to diagnose RDS. European guidelines recommend surfactant administration when patients need fraction of inspired oxygen exceeding 0.3 on continuous positive airway pressure or intubation. We hypothesized that the European guidelines for surfactant administration were not adopted in Japan because of the lack of RDS diagnosis. This study aimed to investigate neonatologists' attitudes and practices regarding the diagnosis and management of RDS in Japan.

METHODS

A mail-based survey regarding the diagnosis and management of RDS was conducted at 111 level III or ΙV neonatal intensive care units in Japan. The questionnaire was completed by the person in charge of each unit.

RESULTS

The overall response rate for the questionnaire was 91% (101/111 centers). All respondents referred to chest radiography, and the majority (83%) of respondents referred to stable microbubble rating (SMR) for establishing the diagnosis of RDS. Surfactant administration was chiefly based on clinical conditions, chest radiography, and/or SMR. Most units in Japan do not adopt the European criteria for surfactant administration.

CONCLUSION

In Japan, chest radiography and/or SMR are commonly used for the diagnosis of RDS and as the rationale for surfactant administration. Further studies from other countries are required to establish the ideal criteria for surfactant administration.

A New Approach of Several Minimally Invasive Procedures for Improvement of the Outcome in Preterm Infants

BACKGROUND: Based on the last update of European Consensus Guidelines on Management of Respiratory Distress Syndrome, the following study is new for our clinic approach for minimally invasive respiratory support in preterm infants. AIM: The aim is to find out if the implementation of several minimally invasive procedures leads to a reduction of the frequency and severity of chronic complications and improved outcomes in extremely premature infants. MATERIALS AND METHODS: Infants are below 30 gestational weeks, divided into two groups – therapeutic – 37 infants on standardized early respiratory management protocol which includes: High-flow continuous positive airway pressure (20l/min ≥ 15 PEEP) in the delivery room, support of spontaneous breathing and non-invasive mechanical ventilation, avoidance of hypothermia and LISA shortly after birth, and control group – 46 infants that received standard respiratory support (positive pressure ventilation – invasive and non-invasive in the delivery room, most infants ≤ 27 weeks gestational age were intubated and received early surfactant, extubation “when being ready” – usually after few days). RESULTS: The duration of mechanical ventilation, oxygen therapy, and hospital stay is shorter in the therapeutic group (p < 0.05). Severe bronchopulmonary dysplasia is not found in the interventional group, 26% of the patients in the control group have severe form of the disease (p = 0.001). Severe intraventricular hemorrhages are found in 11% of the infants in the therapeutic group and 28% in the control group (p = 0.06). CONCLUSION: Due to the changed protocol, we report increased survival of ELBW infants without severe chronic complications. The acute pulmonary injury, acquired in the perinatal period, is directly connected with the development of BPD. For this reason, all the changes that we introduced in our clinic (heat management, support of spontaneous breathing, “open up” lungs – high flow PEEP/CPAP, and LISA during spontaneous breathing) contribute to the lower frequency of severe chronic complications and high percentage of ELBW infants, who do not develop severe BPD.

Two-year outcome data suggest that less invasive surfactant administration (LISA) is safe. Results from the follow-up of the randomized controlled AMV (avoid mechanical ventilation) study

Less invasive surfactant administration (LISA) is a method to deliver surfactant to spontaneously breathing premature infants via a thin catheter. Here we report the two-year outcome from the AMV (avoid mechanical ventilation) study, the first randomized controlled trial on this mode of surfactant delivery. No statistically significant differences in weight, length or neurodevelopmental outcome (Bayley II scores) were found between the LISA intervention group (n = 95) and the control group (n = 84) that received standard treatment.Conclusion: No differences in outcome were observed at 2 years. LISA seems safe in that aspect. What is Known: • LISA is a method that is in increasing use for surfactant delivery to spontaneously breathing infants. LISA reduces the need for mechanical ventilation. What is New: • Outcome data at 2 years from the first randomized study with LISA raise no safety concerns in comparison to a group of infants that received standard treatment.

[Efficacy and safety of less invasive surfactant administration in the treatment of neonatal respiratory distress syndrome: a Meta analysis]

OBJECTIVE

To evaluate the efficacy and safety of less invasive surfactant administration (LISA) in the treatment of neonatal respiratory distress syndrome (NRDS).

METHODS

PubMed, Cochrane Library, Embase, China Biology Medicine disc, China Scientific Journal Database, CNKI Database, and Wanfang Database were searched for randomized controlled trials (RCTs) on the use of LISA strategy in the treatment of NRDS. Literature screening and quality assessment were performed according to inclusion and exclusion criteria. Review Manager 5.3 software was used to perform the Meta analysis.

RESULTS

A total of 9 RCTs were included, with a total of 1 212 children with NRDS. There were 611 children in the experimental group (treated with LISA strategy) and 601 children in the control group [treated with intubation-surfactant-extubation (INSURE) strategy]. The Meta analysis showed that the use of LISA strategy reduced the rate of mechanical ventilation within 72 hours after birth (OR=0.39, 95%CI: 0.29-0.51, P<0.001) and the incidence rates of bronchopulmonary dysplasia (OR=0.53, 95%CI: 0.38-0.72, P<0.001) and pneumothorax (OR=0.56, 95%CI: 0.33-0.93, P=0.02). There were no significant differences in the mortality rate and incidence rates of other neonatal diseases between the two groups (P>0.05). There was no significant difference in the rate of repeated use of pulmonary surfactant (PS) between the two groups (P>0.05), but there was a higher incidence rate of PS reflux observed by LISA strategy (OR=2.60, 95%CI: 1.64-4.12, P<0.001).

CONCLUSIONS

Compared with INSURE strategy, LISA strategy has advantages in reducing the need for mechanical ventilation and the incidence rates of bronchopulmonary dysplasia and pneumothorax in children with NRDS.

Genetic Polymorphisms of LPCAT1, CHPT1 and PCYT1B and Risk of Neonatal Respiratory Distress Syndrome among a Chinese Han Population

BACKGROUND

The study of genetic polymorphisms of surfactant-lipids related genes can help to understand individual variability in the susceptibility to development of pulmonary pathologies. The purpose of this study was to evaluate the association of polymorphisms of surfactant-lipids related genes (LPCAT1, CHPT1 and PCYT1B) with the risk/severity of respiratory distress syndrome (RDS) in preterm neonates among the Chinese Han population in Southern China.

METHODS

Four hundred and forty-six preterm neonates were enrolled in a case-control study. Six polymorphisms of 3 genes were analyzed by PCR amplification of genomic DNA and genotyping was performed using an improved multiplex ligation detection reaction (iMLDR) technique based on LDR.

RESULTS

The GG genotype and G allele of LPCAT1-rs9728 were found less frequently in the RDS group than in the controls (11.5% vs. 22.0% and 38.3% vs. 48.2%, respectively) (p < 0.05).

CONCLUSION

This report is the first study to evaluate a direct genetic association between polymorphisms of LPCAT1 and RDS development in Chinese Han preterm infants. Our study raises the possibility that a genetic variation of LPCAT1 could be implicated in the pathophysiology of RDS in preterm neonates. GG genotype and G allele of rs9728 are protective factors for the development of RDS in preterm infants.

Present and Future of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is the most common respiratory disorder among infants born extremely preterm. The pathogenesis of BPD involves multiple prenatal and postnatal mechanisms affecting the development of a very immature lung. Their combined effects alter the lung's morphogenesis, disrupt capillary gas exchange in the alveoli, and lead to the pathological and clinical features of BPD. The disorder is ultimately the result of an aberrant repair response to antenatal and postnatal injuries to the developing lungs. Neonatology has made huge advances in dealing with conditions related to prematurity, but efforts to prevent and treat BPD have so far been only partially effective. Seeing that BPD appears to have a role in the early origin of chronic obstructive pulmonary disease, its prevention is pivotal also in long-term respiratory outcome of these patients. There is currently some evidence to support the use of antenatal glucocorticoids, surfactant therapy, protective noninvasive ventilation, targeted saturations, early caffeine treatment, vitamin A, and fluid restriction, but none of the existing strategies have had any significant impact in reducing the burden of BPD. New areas of research are raising novel therapeutic prospects, however. For instance, early topical (intratracheal or nebulized) steroids seem promising: they might help to limit BPD development without the side effects of systemic steroids. Evidence in favor of stem cell therapy has emerged from several preclinical trials, and from a couple of studies in humans. Mesenchymal stromal/stem cells (MSCs) have revealed a reparatory capability, preventing the progression of BPD in animal models. Administering MSC-conditioned media containing extracellular vesicles (EVs) have also demonstrated a preventive action, without the potential risks associated with unwanted engraftment or the adverse effects of administering cells. In this paper, we explore these emerging treatments and take a look at the revolutionary changes in BPD and neonatology on the horizon.

Less invasive surfactant administration: best practices and unanswered questions

PURPOSE OF REVIEW

The purpose of this review is to describe current concepts in the field of Less Invasive Surfactant Administration (LISA). The use of continuous positive airway pressure (CPAP) has become standard for the treatment of premature infants with respiratory problems throughout the world. However, if CPAP fails, technologies like LISA are needed that can combine surfactant delivery and spontaneous breathing with the support of noninvasive modes of ventilation.

RECENT FINDINGS

LISA with thin catheters has been in use in Germany for more than 15 years. In the last 5 years, there was substantial interest in this method around the world. Randomized studies and recent metaanalyses indicate that the LISA technique helps to avoid mechanical ventilation especially in emerging respiratory distress syndrome (RDS). LISA is also associated with improved outcomes of preterm infants, specifically in the prevention of bronchopulmonary dysplasia (BPD) and intracranial hemorrhage (ICH). By now, a variety of different LISA catheters, devices and techniques have been described. However, most of the technologies are still connected with the unpleasant experience of laryngoscopy for the affected infants, so that the search for even less invasive techniques, for example, surfactant application by nebulization, goes on.

SUMMARY

Maintenance of spontaneous breathing with support by the LISA technique holds big promise in the care of preterm infants. Patient comfort and lower complication rates are strong arguments to further investigate and promote the LISA approach. Open questions include exact indications for different patient groups, the usefulness of devices/catheters that have recently been built for the LISA technique and -- perhaps most urgently -- the issue of analgesia/sedation during the procedure. Studies on long-term outcome after LISA are under way.

Early surfactant replacement guided by lung ultrasound in preterm newborns with RDS: the ULTRASURF randomised controlled trial

This study aimed to investigate whether using lung ultrasound (LUS) scores in premature newborns with respiratory distress syndrome (RDS) allows for earlier surfactant therapy (within the first 3 h of life) than using FiO₂ criteria. This was a randomised, non-blinded clinical trial conducted in a neonatal intensive care unit. The inclusion criteria were newborns with a gestational age of ≤ 32 weeks and RDS. Patients meeting the inclusion criteria were randomly assigned to two groups: the ultrasound group, administered surfactant based on LUS score and/or FiO₂ threshold, and the control group, guided by FiO₂ only. Fifty-six patients were included. The ultrasound group received surfactant earlier (1 h of life vs. 6 h, p < 0.001), with lower FiO₂ (25% vs. 30%, p = 0.016) and lower CO₂ (48 vs. 54, p = 0.011). After surfactant treatment, newborns in the ultrasound group presented a greater SpO₂ (p = 0.001) and SpO₂/FiO₂ ratio (p = 0.012).Conclusions: LUS score allowed an earlier surfactant therapy, reduced oxygen exposure early in life and a better oxygenation after the treatment. This early surfactant replacement may lead to reduced oxygen exposure. What is Known: • Lung ultrasound scores predict the need for surfactant therapy in premature newborns. What is New: • This study shows that using lung ultrasound scores improves the timeliness of surfactant replacement compared with using FiO₂ alone.

Less invasive surfactant administration (LISA): chances and limitations

Non-invasive ventilation and especially the application of continuous positive airway pressure (CPAP) has become standard for the treatment of premature infants with respiratory problems. However, CPAP failure may occur due to respiratory distress syndrome, that is, surfactant deficiency. Less invasive surfactant administration (LISA) aims to provide an adequate dose of surfactant while the infant is breathing spontaneously, thus avoiding positive pressure ventilation support. Using a thin catheter for surfactant application allows infants to maintain function of the glottis and continue spontaneous breathing, whereas the INtubate-SURfactant-Extubate (INSURE) procedure is connected with sedation/analgesia, regular intubation and a (brief) period of positive pressure ventilation. Individual studies and meta-analyses summarised in this review point in the direction that LISA is more effective than standard treatment or INSURE both in terms of short-term (avoidance of mechanical ventilation) and long-term (intracerebral haemorrhage and bronchopulmonary dysplasia) outcomes. Open questions include exact treatment thresholds for different gestational ages, the usefulness of devices/catheters that have recently been purpose-built for the LISA technique and especially the question of analgesia/sedation during the procedure. The current technology still demands laryngoscopy with all its unpleasant effects for infants. Therefore, studies with pharyngeal surfactant deposition immediately after delivery, the use of laryngeal airways for surfactant administration and attempts to nebulise surfactant are under way. Finally, LISA is not simply an isolated technical procedure for surfactant delivery but rather part of a comprehensive non-invasive approach supporting the concept of a gentle transition to the extrauterine world enabling preterm infants to benefit from the advantages of spontaneous breathing.

Efficacy of pulmonary surfactant combined with high-dose ambroxol hydrochloride in the treatment of neonatal respiratory distress syndrome

Clinical efficacy of pulmonary surfactant combined with high-dose ambroxol hydrochloride in the treatment of neonatal respiratory distress syndrome (NRDS) was investigated. One hundred child patients with NRDS in Linyi Central Hospital were collected according to the diagnostic criteria for RDS in the Pediatrics, and randomly divided into the treatment group (n=50) and the control group (n=50) based on different therapeutic methods. Patients in the control group were treated with basic treatment and high-dose ambroxol hydrochloride injection, while those in the treatment group were additionally administered with pulmonary surfactant Curosurf based on conventional therapy in the control group. The chest X-rays were collected before the treatment and at 12 h after the drug administration, the degree of respiratory distress in child patients was observed and evaluated via Silverman grading, and changes in blood gas indexes were recorded before treatment and at 2, 6 and 12 h after the drug administration. The chest X-ray grade, Silverman grade and blood gas analysis results had no differences between the two groups before the treatment (P>0.05). In the treatment group, partial pressure of oxygen (PaO₂) and PH were increased and partial pressure of carbon dioxide (PaCO₂) was decreased compared with those in the control group at 2, 6 and 12 h after the drug administration (P<0.05). At 12 h after the drug administration, chest X-ray grade and Silverman grade in both groups were improved, which were significantly superior in the treatment group to those in the control group (P<0.01). Moreover, the efficacy in the treatment group was remarkably better than that in the control group at 12 h after drug administration (P<0.01). Pulmonary surfactant combined with high-dose ambroxol hydrochloride has definite efficacy in the treatment of NRDS, which can significantly improve the pulmonary infection, respiratory distress and blood gas indexes of child patients.

Surfactant Administration via Thin Catheter: A Practical Guide

Exogenous surfactant replacement is the most effective evidence-based therapy for respiratory distress syndrome in preterm infants. The mode of administration has evolved in the last decade towards less invasive techniques that aim to effectively provide an adequate dose of surfactant, while allowing spontaneous respiration to continue, and with the support of continuous positive airway pressure. Surfactant delivery via aerosolisation, pharyngeal instillation, and laryngeal mask are being actively pursued in research, but have not yet been adopted to any significant degree in clinical practice. Surfactant administration via thin catheter, on the other hand, is becoming more widely used in neonatal intensive care units worldwide and is now an acknowledged alternative to the standard mode of surfactant delivery. Different devices, including nasogastric tubes, vascular catheters, and purpose-built surfactant instillation catheters are used. We present here a contemporary review of surfactant administration via thin catheter, in a practical guide format that reflects the individual and collective scientific opinions of the clinicians who participated in formulating the guide.