Development and Testing of a Bubble Bi-Level Positive Airway Pressure System

Neonatal respiratory distress results in > 1 million annual deaths worldwide. Bubble CPAP is a simple, effective, and widely used therapy for infants in respiratory distress. In low-resource settings, more advanced respiratory support is limited by cost, technical expertise, and sporadic electricity. We sought to develop a safe, inexpensive, and simple solution to provide further respiratory support for these infants.

A standard bubble CPAP system was modified to provide 2 levels of positive airway pressure (bi-level positive airway pressure) by attaching a novel device. To demonstrate reliability, the system was run with continuous pressure monitoring on full-term and preterm neonatal mannikins with pressure targets of 8/5 cm H₂O and 15/5 cm H₂O to simulate 2 different modes of noninvasive ventilation (NIV).

At a ventilation rate set between 30 and 45 cycles/min, by adjusting the leak rate of the device, the following mean pressures ± SD were demonstrated: term mannikin low-pressure NIV, 7.9 ± 0.2/5.3 ± 0.2 cm H₂O; term mannikin high-pressure NIV, 15.1 ± 0.1/6.1 ± 0.1 cm H₂O; preterm mannikin low-pressure NIV, 7.9 ± 0.2/5.3 ± 0.2 cm H₂O; preterm mannikin high-pressure NIV, 16.5 ± 0.4/5.1 ± 0.1 cm H₂O.

The modified bubble CPAP system reliably provided alternating pressures similar to bi-level positive airway pressure modes of respiratory support in neonatal mannikins. The dual-pressure technology is a simple, single connection add-on that can readily be applied to existing bubble CPAP systems.