Hyperventilation occurs when a person takes quick, deep breaths from the top of their chest. These quick, deep breaths reduce the level of carbon dioxide (CO2) in the blood. This reduced level of CO2 causes the arteries to constrict, reducing the flow of blood throughout the body. When this occurs, the brain and body will experience a shortage of oxygen.

Hyperventilation may occur due to a number of causes, most of them related to anxiety, fear or irrational emotional outbursts. Reassurance of the casualty and a calm approach often lead to the condition being quickly relieved.

• Rapid deep respirations
• Rapid pulse
• Shortness of breath
• Pressure, tightness or pain across the chest
• Anxiety
• Dry mouth
• Blurred vision

In extreme cases which have continued for some time

• Tingling in fingers and toes
• Hand and finger spasms and pain
• Fainting

• Reassurance
• Remove the cause of anxiety if possible
• If fainted, lay casualty down with legs elevated
• If symptoms persists let the patient re-breath his own exhaled air from a paper bag, as re-breathed air has a higher percentage of CO2