The peak inspiratory flow rate (PIFR) measures the function of the airways, identifies reduced breathing on inspiration, and is totally dependent on the effort the patient makes to inspire. The PIFR is the maximal flow of air achieved during a forced maximal inspiration.
Have the patient either sit or stand. Place nose clips on the nose and instruct the patient to breathe normally through a mouthpiece/filter (bacterial/viral) combination into the spirometer.
Ask the patient to take a maximal inspiration forcibly and completely exhale into the spirometer and then inspire forcibly and completely again.
Have the patient repeat this maneuver a minimum of three times. Report the highest value.
The PIFR can also be measured with a handheld peak flow meter.
PIFR is reduced in neuromuscular disorders, with weakness or poor effort, and in extrathoracic airway obstruction (i.e., substernal thyroid, tracheal stenosis, and laryngeal paralysis).
The PIFR is decreased in upper airway obstruction.
Pretest Patient Care
Explain the purpose and procedure of the test. Assess the patient’s ability to follow verbal instructions.
Follow guidelines in Chapter 1 for safe, effective, informed pretest care.
Posttest Patient Care
Evaluate for dizziness, shortness of breath, or chest discomfort. Usually, these symptoms are transitory and subside after a short rest. If symptoms persist, use established follow-up protocols.
Review test results; report and record findings. Modify the nursing care plan as needed.
Counsel regarding possible further testing and treatment.
Follow guidelines in Chapter 1 for safe, effective, informed posttest care.
Poor patient effort compromises the test.
Inability to maintain an airtight seal around the mouthpiece.