Bubble CPAP has become an important part of the management of neonatal respiratory distress syndrome since its introduction more than 30 years ago. Bubble CPAP devices, like “ventilator-derived” or “machine-derived” CPAP devices, apply pressure to the neonatal respiratory system through nasal prongs placed into the infant's nostrils, forming a tight seal to minimize leak.
Bubble CPAP devices, on the other hand, are much simpler than ventilator-derived CPAP, frequently consisting only of humidified bias flow delivered into the inspiratory limb and the CPAP level set based on the distance the expiratory limb of the circuit is submerged in a water seal chamber. The ease of use of this system appeals to many centers, particularly resource-constrained neonatal units in developing countries.
Bubble Continuous Positive Airway Pressure (bCPAP) is a life-saving treatment for children and newborns who are experiencing respiratory distress. An air source with a blender that adjusts the oxygen concentration, a nasal interface that delivers the gas to the patient, and a pressure-generating water reservoir comprise a typical bCPAP circuit.
Bubble CPAP is also mechanically distinct from ventilator-derived CPAP. The mean pressure applied to the infant's airway in bubble CPAP is resonant rather than constant, as it is in ventilator-derived systems, with the airway pressure fluctuating approximately 4 cm H2O around the mean.
The bubbling that occurs when the bias flow reaches the water seal chamber causes this resonance. In a bubble CPAP system, for example, where the expiratory limb of the circuit is immersed in 5 cm H2O, the pressure applied to the airway may actually “oscillate” between 3 and 7 cm H2O.
These pressure swings are caused by pressure amplitudes generated by bubbling in the water seal chamber and reflected back through the circuit's expiratory limb. Several studies have suggested that this “noise” contributes to alveolar recruitment and airway patency, and is thus likely responsible for some of the beneficial effects of bubble CPAP on gas exchange, lung volumes, and outcomes in neonates with neonatal respiratory distress syndrome.
Furthermore, this effect appears to be most pronounced shortly after birth, when compliance is low and oscillating pressure amplitudes are minimally dampened as they pass through the respiratory system.
Bubble CPAP is a non-invasive, gentle form of respiratory support
It has been demonstrated to be both safe and effective. It can help avoid intubation and mechanical ventilation if used immediately after birth. Bubble CPAP has several advantages, including the generation of wave-like oscillations, which can alleviate surfactant deficiency and respiratory distress syndrome.
When compared to endotracheal intubation and mechanical ventilation, bilevel continuous positive airway pressure (bCPAP) is a less invasive intervention.
Bubble CPAP is most appropriate for preterm and young infants with mild to moderate respiratory disease. As a result, bCPAP is not the best intervention for infants who are heavily sedated or have severe lung disease. It is known as the gentlest respiratory support because it applies the least amount of pressure to the delicate neonatal lungs while providing little to no oxygen.
Bubble CPAP helps infants who can breathe on their own but cannot generate enough pressure to keep breathing for an extended period of time. These infants are only on bCPAP until they can generate enough pressure indefinitely and no longer require it. The use of bCPAP has been linked to a lower risk of chronic lung disease, a common condition in premature infants.
Although bCPAP is a simple bedside intervention, it necessitates the use of a specialized team to apply and monitor its use. When compared to national averages, neonatal units that use bCPAP have a lower incidence of chronic lung disease and better outcomes. In these units, a unique culture of enhanced bedside management must be established, and its success is dependent on family cooperation.
Infants managed with bCPAP are generally stable, and as a result, they may be able to benefit from Kangaroo care during earlier stages of development than infants intubated and mechanically ventilated. When infants on bCPAP reach the appropriate maturity, they are encouraged to feed by mouth (usually around 34 weeks corrected gestational age or post conceptual age).
