NONINVASIVE MODES OF RESPIRATORY SUPPORT
CPAP
Initially delivered via endotracheal tube (now rarely used except as a pre-
extubation trial).
Later delivered via a variety of devices including nasal prongs.
Essentially became PEEP with the introduction of infant ventilators.
Recent studies have shown early CPAP use leads to a 20% reduction rate in
mechanical ventilation and is associated with lower rates of BPD.
Now delivered via nasal prongs connected to ventilators and flow drivers.
Bubble CPAP
Uses an underwater seal to create distending pressure.
CPAP is regulated by submerging expiratory limb of gas circuit a set distance
under water to create distending pressure.
Generates a variable distending pressure that is referred to the “noise” of
BCPAP.
Distending pressure is flow dependent and intra-prong pressures may be higher
than what is expected from depth of submersion in water (approximately 1.3 cm
H2O higher).
High-Flow Nasal Cannula (HFNC)
Flow rates greater than 2 L/min.
Advantages over low-flow or “regular” nasal cannula:
Washout of nasopharyngeal dead space leads to improved CO2 clearance
and increased FIO2 in alveoli.