Can we balance early exogenous surfactant therapy and non-invasive respiratory support to optimise outcomes in extremely preterm infants? A nuanced review of the current literature

Prospective, non-blinded, randomized controlled trial on early administration of pulmonary surfactant guided by lung ultrasound scores in very preterm infants: study protocol

Background

Bedside lung ultrasonography has been widely used in neonatal intensive care units (NICUs). Lung ultrasound scores (LUS) may predict the need for pulmonary surfactant (PS) application. PS replacement therapy is the key intervention for managing moderate to severe neonatal respiratory distress syndrome (NRDS), with early PS administration playing a positive role in improving patient outcomes. Lung ultrasonography aids in the prompt diagnosis of NRDS, while LUS offers a semi-quantitative assessment of lung health. However, the specific methodologies for utilizing LUS in clinical practice remain controversial. This study hypothesizes that, in very preterm infants [<32 weeks gestational age (GA)] exhibiting respiratory distress symptoms, determining PS application through early postnatal LUS combined with clinical indicators, as opposed to relying solely on clinical signs and chest x-rays, can lead to more timely PS administration, reduce mechanical ventilation duration, improve patient outcomes, and lower the occurrence of bronchopulmonary dysplasia (BPD).

Methods and design

This is a protocol for a prospective, non-blinded, randomized controlled trial that will be conducted in the NICU of a hospital in China. Eligible participants will include very preterm infants (< 32 weeks GA) exhibiting signs of respiratory distress. Infants will be randomly assigned in a 1:1 ratio to either the ultrasound or control group. In the ultrasonography group, the decision regarding PS administration will be based on a combination of lung ultrasonography and clinical manifestations, whereas in the control group, it will be determined solely by clinical signs and chest x-rays. The primary outcome measure will be the mechanical ventilation duration. Statistical analysis will employ independent sample t-tests with a significance level set at α = 0.05 and a power of 80%. The study requires 30 infants per group (in total 60 infants).

Results

This study aims to demonstrate that determining PS application based on a combination of LUS and clinical indicators is superior to traditional approaches.

Conclusions

This approach may enhance the accuracy of NRDS diagnosis and facilitate early prediction of PS requirements, thereby reducing the duration of mechanical ventilation. The findings of this research may contribute valuable insights into the use of LUS to guide PS administration.

Early Bubble CPAP Protocol Implementation and Rates of Death or Severe BPD

BACKGROUND

A multidisciplinary comprehensive protocol to use bubble continuous positive airway pressure (bCPAP) as the primary respiratory support in the delivery room (DR) and the NICU was introduced. With this study, we aimed to assess the association of this change with respiratory outcomes over time.

METHODS

Infants with gestational age <32 weeks and birth weight <1250 g admitted between January 2012 and June 2020 were included and categorized into 4 periods, including pre-implementation (P0: 2012-2014), and post-implementation (P1: 2014-2016, P2: 2016-2018, P3: 2018-2020). The primary outcome was the rates of death and severe bronchopulmonary dysplasia (BPD), and the secondary outcomes included the rates of DR and NICU intubation ≤7 days of age, need of surfactant, and pneumothorax. Multivariate logistic regression models accounting for relevant risk factors were used to calculate adjusted odds ratios (ORs).

RESULTS

The study included 440 infants (P0 = 90, P1 = 91, P2 = 128, P3 = 131). Over time, more infants were free of BPD (P < .001), and the rates of death and severe BPD decreased significantly: P1 = OR 1.21 (95% confidence interval [CI] 0.56-2.67), P2 = OR 0.45 (95% CI 0.20-0.99), and P3 = OR 0.37 (95% CI 0.15-0.84). DR intubation decreased from 66% (P0) to 24% (P3) in the entire cohort (P < .001) and from 96% (P0) to 40% (P3) in infants <26 weeks of age (P < .001). The need for NICU intubation was similar (P = .98), with a decreased need for surfactant (P = .001) occurring at higher FiO2 (P0 = 0.35 vs P3 = 0.55, P < .001). Pneumothorax rates were unchanged.

CONCLUSIONS

In very preterm infants, the implementation of a comprehensive bCPAP protocol led to a significant and consistent improvement in respiratory practices and the rates of death and severe BPD.

Respiratory Severity Score and Oxygen Saturation Index during the First 2 Hours of Life as Predictors for Noninvasive Respiratory Support Failure in Respiratory Distress Syndrome

OBJECTIVE

 Noninvasive respiratory support (NRS) failure is common in preterm infants with respiratory distress syndrome (RDS). We evaluated the utility of respiratory severity score (RSS) and oxygen saturation index (OSI) during the first 2 hours of life (HOL) as predictors for NRS failure in moderate preterm infants.

STUDY DESIGN

 We conducted a retrospective cohort study of infants born between 280/7 and 336/7 weeks with RDS. Univariate and multivariable logistic regression analyses were used to assess whether the RSS and OSI summary measures were associated with NRS failure.

RESULTS

 A total of 282 infants were included in the study. Median gestational age and birth weights were 32 weeks and 1.7 kg, respectively. Fifty-eight infants (21%) developed NRS failure at the median age of 10.5 hours. RSS and OSI summary measures in the first 2 HOL were associated with NRS failure within 72 HOL.

CONCLUSION

 RSS and OSI during the first 2 HOL can predict NRS failure. Optimal RSS and OSI cutoffs for the prediction of NRS failure need to be determined in large cohort studies.

KEY POINTS

· Nearly one in five moderate preterm infants on NRS at 2 hours of life developed NRS failure.. · RSS and OSI during the first 2 HOL can predict NRS failure.. · Optimal RSS and OSI cutoffs for the prediction of NRS failure need to be determined..

High vs low CPAP strategy with aerosolized calfactant in preterm infants with respiratory distress syndrome

BACKGROUND

Optimal CPAP strategy to prevent CPAP failure defined as need for endotracheal intubation is unknown.

OBJECTIVE

To evaluate the risk of CPAP failure in infants treated with high vs low CPAP strategy while receiving aerosolized calfactant in the AERO-02 clinical trial and AERO-03 expanded access program.

METHODS

Infants born between 29 0/7 to 36 6/7 weeks were included. Comparisons were made between low and high CPAP groups (Low, 4-7 cm H2O; High, 8-10 cm H2O).

RESULTS

CPAP failure and pneumothorax were not different between the groups. Odds of CPAP failure were not different after adjustment for baseline characteristics (OR = 0.61; 95% CI: 0.29, 1.24).

CONCLUSION

We found no difference in CPAP failure among infants who received aerosolized calfactant that were treated with high vs low CPAP strategy. Efficacy of high CPAP strategy with aerosolized surfactant treatment needs to be evaluated in future studies.

Coffee to Make LISA-a-go

In August of 1963, Patrick Bouvier Kennedy, the fourth child of Jackie Onassis Kennedy and John F. Kennedy, died less than 48 hours after his birth from respiratory distress syndrome (RDS) of the newborn. His tragic death inspired research into the physiology of RDS, one product of which was the development of surfactant replacement therapies which have saved millions of neonates from a similar fate. Shortly after the demonstration of its efficacy in 1980, exogenous surfactant replacement therapy became the mainstay intervention for RDS.1 Exogenous surfactant was originally administered via an endotracheal tube in mechanically ventilated neonates, a practice which may lead to ventilator-induced injury to the immature lung.