FIG. 14:  What about BiPAP with backup rate? In BiPAP there is positive expiratory positive airway pressure (EPAP) that, like CPAP, is responsible for keeping the upper airway open.  But in addition to EPAP, there is inspiratory positive airway pressure (IPAP) support that is able to ventilate the patient, eg, during CSA.  For this ventilation in a patient during CSA, it is necessary to manually set a backup rate that kicks in during episodes of CSA.    

Importantly, the indication for BiPAP with backup rate is hypercapnic CSA or hypercapnic respiratory failure, with the goal of reducing elevated CO₂ levels.