Humidification In CPAP Therapy

Topical Nasal Steroids and Nasal Symptoms on CPAP

The following information is provided by Fisher & Paykel Healthcare

By Dr. Vanessa MB Jordan Ph.D., Research Scientist, Fisher & Paykel Healthcare

Many patients using nasal CPAP complain of rhinorrhea, nasal congestion and irritation. While nasal symptoms are common in patients prior to commencing treatment, between 30 and 50% of patients on CPAP complain of new or worsening symptoms.

The cause of nasal symptoms on CPAP is contentious but a paper1 suggests that they may be due to mouth leaks. Patients developing mouth leaks expose their nasal mucosa to high unidirectional airflow causing considerable drying and a subsequent increase in nasal resistance. This response can be prevented by fully humidifying the inspired air.

A similar stimulus occurs during inhalation of cold dry air through the nose and the response has been extensively studied by the Johns Hopkins Asthma and Allergy Center. The response can be prevented with muscarinic receptor blockade but is unaffected by either antihistamines or pretreatment with topical nasal steroids2. These observations suggest important differences in the mechanisms of nasal reactions to dry air versus allergen.

Topical nasal steroids may be useful in patients on CPAP with pre-existing allergic rhinitis as they may reduce nasal congestion and the propensity to mouth breathe, but are unlikely to provide significant relief in the majority of patients.