Hypoxia is a medical condition where your body tissues are deprived of an adequate amount of oxygen. Hypoxia can be classified as either local, affecting a part of your body, or general, affecting your whole body. Hypoxia is considered a medical emergency and treatment is needed right away, especially if your brain is at risk of being affected.
Causes
Hypoxia occurs when your body tissues aren’t oxygenated effectively—the specific cause of hypoxia can depend on the type. The different types of hypoxia include:
- Hypoxic hypoxia: The most common cause of hypoxia is hypoxic hypoxia. This occurs when the lungs don’t receive a sufficient amount of oxygen. A decreased supply of oxygen in the air, reduced lung ventilation, or respiratory disease can cause an inadequate saturation of blood oxygen, resulting in hypoxic hypoxia.
Two environmental causes of hypoxic hypoxia are altitude sickness, where the concentration of atmospheric oxygen is decreased, and deep sea diving, where there’s an insufficient supply of oxygen in the breathing gas or rusting cylinder has extracted oxygen.
A respiratory condition such as asthma can also cause hypoxic hypoxia. A severe attack or flare can occur in all ages. During an asthma attack, airways narrow. This narrowing makes it difficult for air to reach your lungs--and coughing uses more oxygen, which can then worsen your symptoms.
Other lung conditions caused by hypoxic hypoxia include chronic obstructive pulmonary disease (COPD), emphysema, bronchitis, and pulmonary edema (fluid in the lungs) - Stagnant hypoxia: Stagnant hypoxia is caused by insufficient blood flow. A decline in blood flow prevents normal blood supply to your tissues.
Stagnant hypoxia is commonly seen in cardiac problems such as heart attack, cardiac arrest, or heart failure. Such heart problems decrease the circulation of blood which limits oxygen supply to vital tissues and organs. - Anemic hypoxia: Hemoglobin is important in carrying oxygen throughout your body. When hemoglobin is deficient anemia can occur, leading to anaemic hypoxia if tissue perfusion is decreased.
Carbon monoxide poisoning can also be a cause of anemic hypoxia. Carbon monoxide and oxygen compete for binding sites on hemoglobin molecules. The carriage of oxygen is prevented when carbon monoxide binds with hemoglobin hundreds of times tighter than oxygen. - Histotoxic hypoxia: Histotoxic hypoxia occurs when the amount of oxygen supplied to the cells is normal, but the cells don’t use the oxygen effectively--due to damaged cells that are unable to extract and absorb oxygen from circulating blood. This can be caused by alcohol or drug abuse and cyanide poisoning.
Symptoms
Symptoms of hypoxia can vary depending on the cause and the rate in which your condition progresses. Common signs and symptoms of hypoxia include:
- Changes in the color of your skin, ranging from blue to cherry red
- Confusion
- Cough
- Fast heart rate
- Rapid breathing
- Shortness of breath
- Sweating
- Wheezing
