Interpret these spirometry graphs and describe the ventilatory defect indicated.

The graphs visually support the spirometry results, indicating a mixed ventilatory defect.

1. Flow-Volume Loop (Top Graph):

   • The expiratory limb (upper curve) shows a significantly reduced peak flow compared to the predicted curve (dashed line).
   • The shape of the expiratory limb is scooped out or concave, particularly in the mid-to-late phase of expiration. This morphology is characteristic of airway obstruction, where airflow is limited, especially from the smaller airways.
   • The overall size of the loop is smaller than predicted, reflecting reduced lung volumes.

2. Volume-Time Curve (Bottom Graph):

   • The total volume exhaled (Forced Vital Capacity, FVC) is markedly lower than the predicted curve, indicating a restrictive component (reduced lung capacity).
   • The curve shows a slower rise to peak volume and a prolonged exhalation time compared to the predicted curve. This slow exhalation is consistent with airway obstruction.