What Are the Causes of Hypoxemia?

Hypoxemia (also known as hypoxia) is the condition of having low blood oxygen, which usually causes shortness of breath. Hypoxemia can be caused by a variety of factors, including airway obstruction, anemia, certain medications, interstitial lung disease, congenital heart disease and low cardiac output.

Airway Obstruction

• Anything that obstructs the passage of air through the lungs is an airway obstruction that can reduce airflow to the lungs. Airway obstruction can be cause by an external item that becomes lodged in the throat, such as food that the person chokes on, or can be caused by disease or infection that causes a growth or substance to accumulate in the airway. Pneumonia can cause airway obstruction and hypoxemia as mucus accumulates in the airway. Chronic obstructive pulmonary disease, emphysema, pulmonary edema, pulmonary embolism, or pulmonary fibrosis are other diseases that can also cause airway obstruction.

Anemia

• Anemia is an iron deficiency in the blood. When blood is low in iron, it doesn't properly absorb oxygen from the body. Hypoxemia caused by anemia is frequently referred to as "anemic hypoxemia" or "anemic hypoxia."

Medication

• Certain medications, particularly narcotics and anesthetics, slow breathing and subsequently lower oxygen levels in the body. Normal amounts of most medications don't slow breathing to levels low enough cause hypoxemia, but overdose or regular abuse of medication can cause hypoxemia.

Interstitial Lung Disease

• Interstitial lung diseases are diseases that cause scarring of the lung tissue. If a lot of surface area on the lungs becomes scarred, oxygen can no longer pass through the lung membrane and seep into the blood stream.

Congenital Heart Disease

• Congenital heart disease is a defect in the heart that is present since birth. These defects can affect the heart valve, disrupting the regular flow of oxygen through the heart, or the walls between each side of the heart. Disruption to the flow of blood through the heart can cause oxygen to absorb improperly. A defect in the walls between each side of the heart can cause the oxygenated blood from one side of the heart to improperly mix with the unoxygenated blood on the other side of the heart, leading to oxygen-deficient blood.

Low Cardiac Output

• Low cardiac output is a condition that causes the blood to pump too slowly through the heart. When blood pumps too slowly through the heart, oxygen absorption can be hindered.