High-Frequency Oscillation Ventilation Versus Conventional Mechanical Ventilation in Very Preterm Infants With Perinatal Acute Respiratory Distress Syndrome: Multicenters Randomized Controlled, Superiority Trial

High-Frequency Oscillation Ventilation Versus Conventional Mechanical Ventilation in Very Preterm Infants With Perinatal Acute Respiratory Distress Syndrome: Multicenters Randomized Controlled, Superiority Trial

Bronchopulmonary dysplasia (BPD) is a complex disorder and remains the most common complication in very preterm infants. Its incidence is increased with gestational age from 95.5% among infants born at 22 weeks' gestation to 22.2% among those born at 29 weeks' gestation. BPD is associated with the increased risks of delayed neurodevelopment and pulmonary impairment. High incidences of BPD and morbidities indicate inadequacy of current management guidelines of BPD.3 Caffeine reduces the development of BPD by lowering the duration of intubation.4 How to further reduce the risk of BPD and the duration of invasive ventilation remain the key focus for neonatologists.

Before 2017, the management guideline of pediatric and adult acute respiratory distress syndrome (ARDS) exclude perinatal triggers-induced ARDS. Moreover, there is insufficient evidence to recommend high-frequency oscillatory ventilation (HFOV) or conventional mechanical ventilation (CMV) as the preferred fist-line therapy in pediatric and adult ARDS. In contrast, HFOV may benefit preterm baboons with acute pulmonary dysfunction-typically due to respiratory distress syndrome (RDS)-by using low tidal volume, supra-physiologically higher respiratory rate, and lower peak inspiratory pressure to enhance oxygenation and gas exchange. The team also reported that use of HFOV is associated with a modest reduction referring to BPD. However, European consensus guideline of RDS only recommend HFOV being a reasonable alternative to CMV when high pressure is needed to achieve adequate lung inflation. Because randomized controlled trials in humans have yielded inconsistent findings.

These differences between animal models-where RDS was induced and treated with surfactant alone-and clinical scenarios, where preterm birth often involved complex etiologies requiring both surfactant and antibiotics for placental insufficiency or intrauterine infection, may be the diagnosis of RDS and ARDS or the mixture of RDS and ARDS. Such findings highlighted the lack of robust evidence for optimizing ventilation strategies in preterm infants born <32 weeks with perinatal ARDS, and the need for well-designed multi-center randomized controlled trials in this high-risk population.

Inclusion criteria

1. GA was between 24+0 and 31+6 weeks.
2. Preterm neonates were admitted to NICU within 1 hours after birth, diagnosed with perinatal ARDS using Montreux guidelines and stable supported by CMV.
3. Stabilization for 2 hours before randomization: FiO2 0.40, mean airway pressure (MAP) 10-14 cmH2O, ≤ 40 bpm of respiratory rate, 90%-94% of SpO2, pH > 7.20, PaCO2 60 mmHg, tidal volume of 5 ml/kg and > 35% of hematocrit (these may be evaluated by arterial blood gas analysis).

Exclusion criteria

Neonates were not included if any of the following criteria were met:

1. Parents or guardians' decision not to participate.
2. Major congenital anomalies or chromosomal abnormalities
3. Need for surgery or more than grade 2nd of IVH before randomization.