How can I differentiate between patients who would benefit from CPAP versus BiPAP in the management of respiratory distress?

Continuous Positive Airway Pressure (CPAP) is generally indicated for patients with respiratory distress who require maintenance of airway patency and alveolar recruitment without the need for ventilatory support to assist with ventilation.

It is typically used in patients who have hypoxemic respiratory failure but can maintain adequate ventilation on their own, such as preterm neonates needing respiratory support to avoid invasive ventilation ¹.

Bilevel Positive Airway Pressure (BiPAP) is more appropriate for patients who require additional ventilatory support, providing two levels of pressure: a higher inspiratory positive airway pressure (IPAP) to assist ventilation and a lower expiratory positive airway pressure (EPAP) to maintain airway patency.

BiPAP is beneficial in patients with hypercapnic respiratory failure or those who have difficulty maintaining adequate ventilation, such as patients with neuromuscular weakness or motor neurone disease, where ventilatory assistance is needed to reduce work of breathing and improve gas exchange ².

Therefore, the differentiation depends on the patient's respiratory status: use CPAP when the primary issue is oxygenation and airway patency without ventilatory failure, and use BiPAP when there is a need for ventilatory support to assist with ventilation and CO2 clearance.