KEYWORDS
bronchopulmonary dysplasia; neonatal respiratory distress syndrome; minimally invasive surfactant administration; intubation-surfactant-extubation strategy; meta analysis1 | INTRODUCTION
Neonatal respiratory distress syndrome (NRDS), one of the most common respiratory diseases in preterm infants, is mainly due to the lack of pulmonary surfactant, which often results in neonatal death1. Exogenous pulmonary surfactant replacement therapy can reduce the incidence of NRDS and neonatal mortality and improve the long-term outcome; therefore, it is currently recognized as the most effective treatment for NRDS 2-4. Previous treatment options for NRDS included mechanical ventilation with surfactant replacement therapy, except that this approach resulted in a high incidence of ventilator-associated lung injury and bronchopulmonary dysplasia (BPD) 5,6. Intubation, surfactant administration, and extubation (INSURE) techniques were later developed, which could effectively reduce the incidence of BPD and the duration of mechanical ventilation 7,8. However, endotracheal intubation can damage the airway 9, and transient positive pressure ventilation can cause significant lung injury10.
In order to prevent intubation for surfactant delivery in preterm infants with NRDS, MISA techniques are recommended, including less invasive surfactant administration (LISA) and minimally invasive surfactant therapy (MIST) 11. These techniques are characterized with the use of a thin catheter for surfactant delivery while the infant breathes spontaneously with the support of nasal continuous positive airway pressure (nCPAP). Nevertheless, it is still unknown whether MISA techniques can reduce the mortality rate, as well as the incidence of BPD and other neonatal complications compared with conventional intubation techniques. Therefore, we systematically searched randomized controlled trials (RCTs), compared MISA techniques with endotracheal intubation for surfactant delivery, and conducted meta-analysis to further clarify their efficacy and safety.
2 | METHODS
This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines 12.
2.1 | Search strategy
Searches were conducted in PubMed, Embase, Cochrane Library, and Web of Science databases from inception to November 4, 2020. Keywords and MeSH terms were as follows: “Infant, Premature”, “Infant, Extremely Premature”, “Premature Birth”, “MISA”, “MIST”, “LISA”, “less invasive”, “minimally invasive”, “thin catheter”, “gastric tube”, “nasogastric tube”, “non-intubated”, “non-intubation”, “noninvasive”, “lung surfactant”, “pulmonary surfactant”, and “surfactant”. We also reviewed the references in each included study to identify any relevant papers that might have been missed from the search.