What is forced expiration spirometry primarily used to assess?

Forced expiration spirometry is primarily used to assess lung volume, particularly the forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). This type of spirometry measures how much air a person can forcibly exhale after taking a deep breath, which helps evaluate the function of the lungs and can indicate the presence of respiratory conditions such as asthma or chronic obstructive pulmonary disease (COPD). By analyzing the results, healthcare providers can determine the degree of airway obstruction and lung compliance, which are essential for diagnosing and managing various pulmonary disorders.

The other options do not pertain to what forced expiration spirometry specifically measures. Heart function is evaluated through different tests such as echocardiograms or electrocardiograms. Body mass index (BMI) is a measure of body fat based on height and weight, not respiratory function. Blood gas levels are assessed through arterial blood gas tests that measure oxygen and carbon dioxide levels in the blood, which is separate from spirometric assessments of lung volumes.