Certified Pulmonary Function Technologist (CPFT) Practice Exam

What characterizes a Mueller maneuver?

1. Forced inhalation attempt with closed mouth and nose

2. Forced exhalation with a closed mouth

3. Normal breathing with an open mouth

4. Rapid inhalation through a straw

The correct answer is: Forced inhalation attempt with closed mouth and nose

A Mueller maneuver is characterized by a forced inhalation attempt with a closed mouth and nose. This maneuver is performed to assess inspiratory muscle strength or to evaluate conditions related to airway obstruction. During a Mueller maneuver, the individual tries to inhale against a closed airway, causing intrathoracic pressure to drop and helping to demonstrate the effects of such pressure dynamics in the respiratory system. The forced inhalation is specifically designed to engage the diaphragm and other inspiratory muscles effectively, offering useful insights into respiratory function. The closed airway situation creates a negative pressure that may reveal certain physiological responses or limitations in lung function. Other options do not accurately describe a Mueller maneuver; for instance, forced exhalation with a closed mouth is more akin to a Valsalva maneuver. Normal breathing with an open mouth does not involve the specific dynamics of forced inhalation against resistance, and rapid inhalation through a straw does not pertain to the maneuver's definition and purpose in evaluating lung functionality.