Reference values of total respiratory resistance, determined with the "opening" interruption technique

Area of Science:

• Pulmonary Physiology
• Respiratory Medicine
• Epidemiology

Background:

• Lung function assessment is crucial for diagnosing respiratory conditions.
• Maximum expiratory flow volume (MEFV) maneuvers and questionnaires are standard tools.
• Measuring respiratory system resistance offers additional insights into lung mechanics.

Purpose of the Study:

• To evaluate the utility of the "opening" interruption technique for measuring respiratory system resistance.
• To establish reference values for respiratory resistance in a healthy population.
• To assess the correlation of resistance with demographic and lung function parameters.

Main Methods:

• A subset of participants from a large lung function survey underwent resistance measurement using the "opening" interruption technique.
• Respiratory resistance was measured during both inspiration and expiration.
• Data were analyzed for correlations with height, FEV1, MEF50, and smoking habits.

Main Results:

• Mean inspiratory and expiratory resistances were similar in healthy men and women.
• Average resistances were 0.28 kPa.l-1.s for men and 0.39 kPa.l-1.s for women.
• Resistance showed slight correlations with height, FEV1, and MEF50, but not smoking habits.

Conclusions:

• The interruption technique demonstrates considerable variability, limiting its use for sharp discrimination between normal and abnormal subjects.
• This method shows potential utility in histamine challenge testing for detecting and monitoring bronchial asthma.
• The technique is advantageous as it is unaffected by forced inspiratory and expiratory maneuvers.