Comparison of Bubble CPAP Devices Using RAM Cannula for Extubation Failure in Very Low Birth Weight Infants: Randomized and Cohort Studies

Introduction: Bubble continuous positive airway pressure (bCPAP) generates a variable pressure due to bubble size and frequency, and these pressure oscillations may contribute to lung recruitment and gas exchange. Single-outlet bCPAP devices generate larger pressure fluctuation than bCPAP devices with diffusers, but clinical efficacy is unclear. Our hypothesis was that a single-outlet bCPAP device (B&B Bubbler^©) would decrease extubation failure and improve oxygenation compared with a bCPAP device with a diffuser (BabiPlus^©). Methods: Bench testing of bCPAP devices with the RAM^© cannula determined pressure averages, fluctuations, and CPAP transmission at prongs. The B&B Bubbler^© and the BabiPlus^© devices were compared for oxygenation and bCPAP failure within 72 h of extubation in a randomized trial in infants less than 1,250 g (n = 43). Additionally, a cohort study with infants extubated to BabiPlus^© (n = 128), B&B Bubbler^© (n = 119), and noninvasive positive pressure ventilation (NIPPV) (n = 107) were compared. Results: Small differences in pressure fluctuations between bCPAP devices are attenuated by the RAM^© cannula. Pressures at RAM^© prongs are 62% of set pressure. The bCPAP extubation failure rate (35%) and oxygenation were similar between the bCPAP devices. bCPAP success was associated with lower FiO₂ at extubation and decreased need for additional FiO₂ in both groups. In the setting of the RAM^© cannula, there were no differences in extubation failure rate for infants extubated to bCPAP or NIPPV. Conclusions: There were no clinical differences at extubation between the B&B Bubbler^© and BabiPlus^© devices. Oxygenation may predict bCPAP failure. The use of the RAM^© cannula as a bCPAP interface should be more closely examined.