How often is PEF measurement necessary?

In most situations a morning PEF measurement before bronchodilator is an adequate test and guide. If using PEF to validate patients’ symptoms, or confirm a diagnosis of occupational asthma, more frequent measurements are required.

How can I identify poor perceivers?

These are patients who accept their chronic asthma symptoms as the norm, or do not recognise that they have symptoms. They live with undertreated asthma. This leads to poor quality of life and puts them at risk of severe attacks.

Check patients to see that they are aware of symptom improvement correlated with a bronchodilator response measured either during formal lung function tests or PEF monitoring. Encourage regular, long-term self-monitoring in patients who fail to recognise symptom improvement with a 15% increase in FEV₁.

How can I encourage PEF measurement in appropriate patients?

• Show your patients how to use a peak flow meter and chart their PEF. (Be wary of common techniques to obtain a higher result, such as bending over to blow into the meter or inserting the tongue into the mouthpiece.)
• Ask your patients to bring their own PEF meter to each consultation – this will ensure that home tests and tests taken in the surgery have comparable results. Check the chart at each visit.
• Discuss the benefits of PEF monitoring with your patients. Only ask the patient to continue if there is benefit – in all but poor perceivers, explain that the monitoring period will be short-term, but can be episodic to provide you with information at reviews.

Content Updated March 2005