Final answer:
When FEV1 or FVC requirements are not met, additional tests such as MVV, SVC, TLC, FRC, and RV are ordered to measure lung volumes, leading to accurate diagnosis of lung diseases.
Step-by-step explanation:
Understanding FEV1/FVC in Lung Function Tests
When minimum FEV1 or FVC requirements are not met during a spirometry test, additional tests may be ordered to diagnose lung conditions. The FEV1/FVC ratio can be used to differentiate restrictive from obstructive lung diseases. A high FEV1/FVC ratio, indicating stiff lungs, could suggest lung fibrosis where patients can rapidly expel air. Conversely, a low FEV1/FVC ratio may indicate an obstructive condition like asthma, with increased resistance in the lungs making exhalation difficult. Possible additional tests include Maximum Voluntary Ventilation (MVV), Slow Vital Capacity (SVC), Total Lung Capacity (TLC), Functional Residual Capacity (FRC), and Residual Volume (RV). These provide more comprehensive lung volume measurements and help in the accurate diagnosis of specific lung diseases.