What is a common indication for performing pulmonary function tests?

Pulmonary function tests (PFTs) are primarily used to evaluate lung capacity and function, making this the correct choice. These tests measure how well the lungs are working, including aspects like the amount of air a person can inhale and exhale, and how effectively oxygen is being exchanged.

PFTs help diagnose various respiratory conditions such as asthma, chronic obstructive pulmonary disease (COPD), interstitial lung disease, and pulmonary fibrosis by providing important data on lung volumes, airflow, and gas exchange efficiency. By assessing these parameters, healthcare providers can determine the degree of lung impairment and guide treatment decisions.

In contrast to evaluating lung function, assessing heart function and analyzing blood pressure pertain to cardiology and are not the focus of PFTs. Although oxygen levels in the blood can be indirectly assessed alongside PFTs, the specific measurements of arterial blood gases (ABGs) or pulse oximetry are typically used for such evaluations, rather than the PFTs themselves. Therefore, options related to heart function, blood pressure, and direct assessment of blood oxygen levels do not align with the primary purpose of pulmonary function tests.