Effort dependent tests - spirometry

FEV1/FVC ratio

• See respiratory physiology II

Flow-volume loop

• Plots flow over volume

Peak Expiratory Flow Rate (PEFR)

• Measure of the fastest flow of exhaled air after a maximal inspiration (peak of graph)

Forced Expiratory Flow Rate

• Average flow rate over the middle half of the expiration (25-75% of FVC)

Exercise testing

• Decreased FEV1 or PEF post exercise → asthma

Effort independent tests

Relaxed vital capacity

• Spirometry

N2 washout static lung volumes

• Method for calculating anatomical dead space - tests functional residual capacity

Airway resistance

• Whole body plethysmography
• Impulse oscillometry
  • Measures airway resistance during quiet tidal breathing using different resonant frequencies

Exhaled breath NO