The peak expiratory flow rate (PEFR) measurement is used as an index of large airway function. It is the maximum flow of expired air attained during a forced expiratory maneuver.
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 PEFR can also be measured with a handheld peak flow meter.
The PEFR usually is decreased in obstructive disease (e.g., emphysema), during acute exacerbations of asthma, and in upper airway obstruction (e.g., tracheal stenosis).
The PEFR usually is normal in restrictive lung disease but is reduced in severe restrictive situations.
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
Monitor patient for dizziness, lightheadedness, or chest pain following the test. Generally, these symptoms are transient and will subside quickly. If not, follow established 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.