10.12 Hyperventilation

10.12.2 Define hyperventilation.

Hyperventilation, often known as “over-breathing”, occurs when a person breathes too rapidly and/or deeply for the body's needs.

This causes excessive carbon dioxide to be breathed out, resulting in a decrease in the level of carbon dioxide in the blood.

Key point

Hyperventilation = over-breathing → too little carbon dioxide in the blood.

10.12.4 Explain the causes of hyperventilation.

Hyperventilation may be triggered by:

• anxiety or panic;
• stress;
• fear;
• pain;
• emotional distress; or
• hypoxia.

Certain medical conditions may also cause excessive breathing.

In aviation, stress, anxiety and hypoxia are particularly important causes.

10.12.6 Describe the symptoms of hyperventilation.

Symptoms of hyperventilation may include:

• rapid or deep breathing;
• a feeling of shortness of breath;
• light-headedness or dizziness;
• tingling or numbness in the hands, feet or around the mouth;
• chest tightness;
• a sensation of not getting enough air;
• palpitations;
• anxiety or panic; and
• muscle spasms in more severe cases.

If hyperventilation continues, it may eventually result in confusion or loss of consciousness.

10.12.8 Describe how hyperventilation can be treated.