What Causes Hypoxia

Oxygen is extremely important, least to say. Try imagining life without oxygen, and it gives us goose bumps! Basically, no life-form would exist without this precious element. Did you know, that ninety percent of our energy has oxygen as a source. Living beings need a specific amount of oxygen to do all the body functions effectively. Deficiency of oxygen in the body invites hordes of problems like - loss of concentration, tiredness, problems with digestion and metabolism, and sleeping disorders, to name a few. 'Hypo' means less of something, and in hypoxia, it is the less of oxygen. Hypoxia specifically affects the tissues of the brain, the heart and the liver. In severe cases, hypoxia can lead to cardiac arrest. The four major types of hypoxia are, hypoxic, hypoxemic, anemic, and histotoxic hypoxia.

The common symptoms of the condition include the following - breathlessness, headache, mental confusion, severe nausea, and tingling sensation. High altitude mountaineering enthusiasts more often experience hypoxia, as concentration of oxygen in the atmosphere tends to decrease with an increase in altitude. A number of factors may result in hypoxic condition in a person, which in simple terms is an imbalance between demand and supply of oxygen to the body.

What Causes Hypoxia?

Hypoxia or shortness of oxygen may occur if there is less oxygen in the surrounding air or if there is something wrong in the functioning of the body. There are external as well as internal causes for hypoxia. We will now take a closer look at the causes based on the four major types.

Hypoxic Hypoxia: Lack of oxygen supply to the lungs is referred to as hypoxic hypoxia. Decreased partial pressure is a common cause for this condition, apart from conditions like COPD, asthma, pulmonary diseases, and neuromuscular diseases.

Hypoxemic hypoxia is when the body, as a whole, is deprived of oxygen due to low partial pressure. Oxygen has a defined partial pressure in the arteries, and this pressure when it goes down, it is called low partial pressure. The various causes of hypoxemic hypoxia are,

• Lack of oxygen due to high altitude.
• Sleep apnea, which is temporary stoppage of breathing during sleep.
• Hypoventiliation, which is a respiratory problem.
• Shunts (small passage which allows the passage of fluid from on part to the other) in the heart.
• Defects such as pulmonary fibrosis.
• Low concentration of oxygen in the surrounding air.

In histotoxic hypoxia, the blood cells have adequate oxygen in them, but they cannot utilize it. The various causes of histotoxic hypoxia are,

• Excessive consumption of alcohol and narcotic drugs.
• Poisoning due to chemicals and harmful gases in haphazardly ventilated area.
• Poisoning due to harmful gases like carbon monoxide and cyanide.

In anemic hypoxia, the body cannot transport available oxygen to the target tissues, due to less amount of blood in the body. There are plenty of cause that can lead to anemic hypoxia (or hypemic hypoxia), have a look:

• Less oxygen in the atmosphere.
• Poisoning due to carbon monoxide.
• Anemia and problems with the circulatory system of the body can deprive the tissues of adequate oxygen.
• Diseases like edema and sickle-cell disease can impair the tissues and lower their oxygen carrying capacity, resulting in hypoxia.
• Medications like sulfonamides and aspirin can also deprive the cells of oxygen.

Stagnant hypoxia occurs when there is a failure to transport oxygen to the cells due to low blood flow rate. Stagnant hypoxia is also known by the name ischemic hypoxia. Cerebral hypoxia is a term used to refer to inadequate supply of oxygen to the brain. The common causes are:

• Low blood pressure.
• Drowning.
• Over dose of certain drugs.
• Poisoning due to harmful gases.
• Injury to the brain.
• Cardiac arrest.
• Strangulation.

Other common causes of hypoxia include:

• Acute asthma problem in the patient.
• Throttling of the neck.
• Inhalation of poisonous gases.
• Vasodilation.
• Pneumonia.
• Smoke inhalation.

Hypoxia may prove fatal if the treatment is not administered on time. After hypoxia is diagnosed, the main aim of any treatment is to regulate the breathing pattern. For treating hypoxia, medications, equipment that supply oxygen, and procedures like oxygen therapy are useful. Unfortunately, the cases of hypoxia may rise in the future, as the oxygen content of air is reducing, day by day due to many man-made reasons. We can contribute our bit to increase oxygen in the air, by planting a sapling each.