Vital capacity is the total amount of air that a person can expire after a maximum inspiration.

Diagnoses

---

A very important tool in determining if a patient has obstructive or restrictive lung disease is the Percent of gas that is expired in the first second of a Forced Expiratory Capacity. Vital capacity is measured by a spirometer. (FEV1/FVC).

• Obstructive lung disease. Obstructive lung disease can be determined by dividing the Forced Vital Capacity in one second (FEV1) by the Forced Vital Capacity (FVC). If the value found is less than 75%, then the patient is known to have Obstructive Lung Disease.
• Restrictive lung disease. Restrictive Lung Disease can be determined by dividing the Residual Volume by the Total lung capacity. If the value is found to be greater than 75% then the patient is said to have Restrictive Lung Disease.

External links

---