Haemodynamic Changes With Different Noninvasive Respiratory Modes for Primary Respiratory Support in Preterm Neonates

• A randomized controlled trial was conducted in the period from September 2021 to September 2022 in a tertiary -level Neonatal Intensive Care Unit (NICU) , Childrens' Hospital, Ain Shams University, Cairo, Egypt. The study was approved by the Research Ethics Committee of the Faculty of Medicine, Ain Shams University; ID: FMASU 179/2021.
• This study included spontaneously breathing preterm neonates with gestational age equal to or less than 35 weeks in need for noninvasive respiratory support during their first 3 days of life for primary treatment of respiration distress syndrome.
• Diagnosis of Respiratory distress syndrome (RDS) was done by clinical examination, including signs of respiratory distress, venous blood gases showing hypoxemia and hypercapnia, and chest X-ray showing diffuse atelectasis, classically described as a ground glass appearance .
• Neonates with upper or lower airway anomalies or significant congenital anomalies were excluded from the study.
• Out of 105 neonates assessed for eligibility, 15 were excluded; 10 guardians declined to participate, and 5 didn't meet the inclusion criteria. Thus, 90 neonates were enrolled.

Out of 105 preterm neonates assessed for eligibility, 15 neonates were excluded: 3 had confirmed congenital heart disease, 2 had cleft palate, and 10 parents/guardians refused to consent . 90 neonates were randomly allocated to the three noninvasive modes using a computer-based randomization program, with 30 neonates in each group. Sealed envelopes containing treatment assignments were opened in a sequential manner. No crossover was allowed in the study.

NHFOV group: was delivered by SLE 6000 device (Wipro GE Healthcare Private Limited, Bengaluru, Karnataka). Settings: amplitude range (20:35) cm H2O, frequency range (8-12) HZ, Mean airway pressure (MAP) range (6:10) cm H2O, and Inspiration :Expiration (I:E) ratio 1:1 to 1:2 in case of air trapping, using nasal prongs .

Vapotherm Group: was delivered by Vapotherm Device (Vapotherm, INC, USA). Settings: flow rate 4-6 L/min, with temperature 36-37 °C and Fraction of inspired oxygen(FiO2) titrated as needed to achieve target Saturation of peripheral oxygen (SpO2) (90% to 94%) using soft nasal cannula interface .

Nasal CPAP Group: was delivered by MEDIN CNO device (Medin Medical Innovations GmbH, Olching, Germany). Settings: pressure ranging from 5 to 8 cm H2O to maintain SpO2 from 90% to 94% using bi-nasal prongs.