airway resistance
The opposition to airflow through the respiratory tract, measured as pressure difference per unit flow.
Full Definition
Airway resistance is the measure of opposition to airflow through the respiratory system, calculated as the pressure difference between the alveoli and the mouth divided by the airflow rate. Normal airway resistance in healthy adults is approximately 0.5-2.0 cmH2O/L/sec. Increased airway resistance can result from bronchospasm, airway inflammation, secretions, or anatomical abnormalities, leading to increased work of breathing and elevated airway pressures during mechanical ventilation. Respiratory therapists monitor airway resistance through ventilator graphics and pressure measurements to guide bronchodilator therapy, airway clearance techniques, and ventilator settings adjustments.
Usage
Usage note: Express in units of cmH2O/L/sec or cmH2O·s/L in clinical documentation.
In Context
- "Elevated airway resistance of 8 cmH2O/L/sec indicates significant bronchospasm requiring bronchodilator therapy." — Pulmonary function assessment
- "Monitor airway resistance trends to evaluate response to nebulizer treatments." — Respiratory therapy treatment plan