Gas flow in preterm infants treated with bubble CPAP: an observational study

Area of Science:

• Neonatal Physiology
• Respiratory Support

Background:

• Bubble continuous positive airway pressure (CPAP) is a common respiratory support method for preterm infants.
• Understanding delivered nasal gas flow is crucial for optimizing therapy and comparing different support modalities like nasal high flow (nHF).

Purpose of the Study:

• To quantify the nasal gas flow delivered to infants during bubble CPAP therapy.
• To compare these measured flows with typical flow rates used in nasal high flow (nHF) treatment.

Main Methods:

• Prospective, single-centre study involving clinically stable preterm infants on bubble CPAP.
• Gas flow was measured at the nasal prongs by reducing the set flow until bubbling in the water chamber ceased.
• Delivered flow was approximated by the set gas flow without bubbling at various CPAP pressures.

Main Results:

• Forty-four preterm infants were studied, with a mean gestational age of 28.4 weeks.
• Delivered nasal gas flow ranged from 0.5 to 9.0 L/min.
• Flow increased with higher set CPAP pressures (e.g., 3.5 L/min at 5 cm H2O vs. 6.3 L/min at 8 cm H2O) and with greater infant weight.

Conclusions:

• Nasal gas flows during bubble CPAP in preterm infants are similar to those used in nHF.
• Delivered flow is influenced by CPAP pressure settings and infant size.
• The findings provide valuable data for respiratory support management in neonates.