Hyperventilation Syndrome (HVS)
Hyperventilation is an increase in alveolar ventilation that leads to hypocapnia. It may be caused by a variety of conditions, such as pregnancy, hypoxemia, obstructive and infiltrative lung diseases, sepsis, hepatic dysfunction, fever, and pain. The term “central neurogenic hyperventilation” denotes a monotonous, sustained pattern of rapid and deep breathing seen in comatose patients with brainstem injury of multiple causes. Functional hyperventilation may be acute or chronic.
Signs and symptoms
HVS can show itself in different ways. Most people with HVS will have experienced some, if not many, of the following symptoms.
- tightness around the chest
- fast breathing
- frequent sighing
- tingling (e.g. in fingers, arms, mouth)
- muscle stiffness
- trembling in hands
- blurred vision
- tachycardia (rapid heart beat)
- cold hands or feet
- warm feeling in the head
- abdominal pain
- fatigue and lethargy
The diagnosis of chronic hyperventilation syndrome is established if symptoms are reproduced during voluntary hyperventilation. Once organic causes of hyperventilation have been excluded, treatment of acute hyperventilation consists of breathing through pursed lips or through the nose with one nostril pinched, or rebreathing expired gas from a paper bag held over the face in order to decrease respiratory alkalemia and its associated symptoms. Anxiolytic drugs may also be useful.