What action should be taken for a patient on bi-level therapy with blood gases indicating hypercapnia (high PaCO2)?

• A. Increase IPAP and EPAP
• B. Increase IPAP
• C. Decrease EPAP
• D. Increase EPAP and IPAP

Answer: (C)

For a patient on bi-level therapy experiencing hypercapnia, the most suitable action involves adjusting the parameters of the therapy to optimize ventilation.

Increasing IPAP (Inspiratory Positive Airway Pressure) is typically the most effective approach when addressing elevated carbon dioxide levels (hypercapnia) because it enhances the patient's ability to take deeper breaths. This helps to improve ventilation by increasing tidal volume and, consequently, lowering the PaCO2 levels.

Decreasing EPAP (Expiratory Positive Airway Pressure) can also facilitate improved ventilation in certain contexts, especially if the EPAP is set too high and is limiting expiratory flow. However, decreasing EPAP alone doesn't directly address the insufficiency in ventilation caused by hypercapnia as effectively as increasing IPAP.

Increasing both IPAP and EPAP has benefits for obstructive disorders, but for hypercapnia, the priority is often to ensure that the inspiratory pressure support is sufficient to clear CO2 effectively. Therefore, the most appropriate adjustment primarily focuses on increasing IPAP to enhance ventilation rather than decreasing EPAP, which might not adequately address the high levels of carbon dioxide in the blood.