What is a significant clinical limitation of simple spirometry?

The significant clinical limitation of simple spirometry is that it cannot measure all lung volumes and capacities. Spirometry primarily assesses the dynamics of airflow during breathing, specifically measuring parameters like forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). However, it does not provide information on residual volume (RV), total lung capacity (TLC), or functional residual capacity (FRC). These lung volumes are important for a comprehensive understanding of pulmonary function and can be critical in diagnosing and managing various respiratory conditions.

Other pulmonary function tests, such as body plethysmography or gas dilution methods, are necessary to obtain complete information about lung volumes and capacities. As a result, while simple spirometry is valuable for evaluating airflow limitations, its inability to measure all lung volumes represents a notable limitation in clinical practice, especially when more detailed assessments of lung mechanics are required.