Hypocapnia

Under hypocapnia is defined as a decreased Kohlenstoffdioxidpartialdruck ( pCO2 below 35 mmHg) in arterial blood.

This hypocapnia may occur ( exhaling of Säurevalenzen ), for example, when rapidly and or deep breathing, known as hyperventilation, or even at respiratory compensation of metabolic acidosis.

An increased Kohlenstoffdioxidpartialdruck is called hypercapnia.

Symptoms and Risks

Hypocapnia causes cerebral vasoconstriction ( vasoconstriction of the brain), which in turn can lead to cerebral hypoxia and thus to dizziness and other symptoms.

In this respect, does not serve the hypocapnia for compensation of acidosis, it causes a respiratory alkalosis. The alkalosis resulting in lowered plasma calcium levels and thus to increased excitability of nerves and muscles. This explains the different symptoms that occur when hypocapnia: muscle cramps at rest, especially in the extremities, tingling and ants.

The CO2 level in the blood is normally used as a respiratory drive. Untrained diver in the swimming pool hyperventilate before diving to range before surfacing much CO2 and thus to be able to stay underwater longer. This should only take place under controlled conditions, as it brings the risk of loss consciousness and drowning (swimming pool blackout ) with itself.