34.12 Hyperventilation

34.12.2 Explain the causes of hyperventilation.

Hyperventilation occurs when a person breathes faster or deeper than the body requires, causing excessive carbon dioxide to be removed from the blood.

In aviation, hyperventilation may be caused by:

• anxiety or panic;

• stress or emotional distress;

• fear;

• pain;

• high workload or excitement;

• deliberately or unintentionally breathing too rapidly; or

• hypoxia, which can stimulate an increase in breathing rate.

Certain medical conditions, such as respiratory illness or metabolic disturbances, may also cause hyperventilation.

In flight, stress, fear and hypoxia are particularly important causes, as the symptoms of hyperventilation and hypoxia can be similar.

34.12.4 Describe the symptoms of hyperventilation.

The symptoms of hyperventilation may include:

• rapid or deep breathing;

• shortness of breath or a feeling of not getting enough air;

• light-headedness or dizziness;

• tingling or numbness, particularly in the hands, feet or around the mouth;

• chest tightness;