Comprehensive Respiratory and Infectious Disease Nursing Practice Test

Maintaining moisture in the airway during oxygen therapy is essential. When oxygen is delivered without humidification, the gas is dry and pulls moisture from the nasal and airway mucosa. This drying of the mucosa causes irritation, crusting, and discomfort, and can impair mucociliary clearance in COPD, making it harder to move mucus. Adding humidity to the inspired gas reintroduces water vapor, keeping the mucous membranes moist and helping mucus flow more easily. Fever or regular exercise might influence overall hydration, but they don’t directly cause the mucosal drying from unhumidified oxygen. Adequate hydration helps overall, yet it doesn’t prevent the direct dryness caused by dry oxygen delivery.