Definition of Peak-flow meter

Peak-flow meter: This hand-held device measures air flow (how fast air is blown out of the lungs). Patients can use peak-flow meters to measure their own air flow regularly.

The use of a peak-flow meter allows patients to obtain a much earlier indication of an oncoming attack, for example, of exercise-induced asthma, a type of asthma typically triggered by exercise.

The "peak flow" refers to the maximum flow rate of air breathed out during forced expiration.