Referring to all systems that bubble as bubble CPAP is misleading and potentially hazardous!
Sonja Baldursdottir and colleagues in their 2020 article published in the Archives of Diseases of Childhood Fetal and Neonatal edition identified three major alterations in newly introduced bubble CPAP systems that are different from the original bCPAP design: 1) resistance of nasal interface, 2) volume of dead space and 3) diameter of expiratory tubing. They conducted a study to examine the effect of these alterations on CPAP delivery and work of breathing in a mechanical lung model. They found out that high-resistance interfaces and narrow expiratory tubing increased the work of breathing. Additionally, narrow expiratory tubing resulted in higher CPAP levels than indicated by the submersion depth. They concluded that using high-resistance interfaces and narrow expiratory tubing significantly impacted CPAP delivery and imposed work of breathing. They recommend that new bubble CPAP systems should include low-resistance interfaces and wide-bore tubing and be compared with the original bCPAP.
Baldursdottir S, et al. Arch Dis Child Fetal Neonatal Ed 2020; 0:F1–F5. doi:10.1136/fetalneonatal-2019-318073