Hepatopulmonary syndrome

Overview

Hepatopulmonary syndrome is a condition in which low oxygen levels in the blood are caused by enlarged blood vessels in the lungs. Hepatopulmonary (hep-uh-toe-POOL-moe-nar-e) syndrome affects the lungs of some people who have advanced liver disease.

When the tiny blood vessels in the lungs become enlarged, also called dilated, it's more difficult for red blood cells to take in oxygen. This results in the body not having enough oxygen. The exact link between advanced liver disease and this lung condition isn't yet known.

Oxygen therapy may improve blood oxygen levels to some degree. A liver transplant is the only way to correct hepatopulmonary syndrome.

Symptoms

Early in the disease, there are often no symptoms of hepatopulmonary syndrome. Symptoms usually develop and worsen gradually. They may include the following:

• Shortness of breath. This is usually the first symptom. Often, it's worse when sitting or standing, and it gets better when lying flat on the back.
• Clubbing of the fingers. This is where the fingertips become rounder than usual.
• Spider angioma. This is the term for tiny blood vessels that appear below the surface of the skin that look somewhat like spiders.
• Cyanosis. This is a change in skin color caused by low blood oxygen. The color of the skin and lips may be pale blue or gray.

Causes

Hepatopulmonary syndrome is a complication of advanced liver disease.

Hepatopulmonary syndrome also may be caused by portal hypertension. This is high blood pressure in the vein that brings blood to the liver to be filtered. Portal hypertension is often caused by long-term liver disease, but it also can happen when there is no underlying liver disease.

Researchers continue to explore the link between liver disease and hepatopulmonary syndrome.

Disease-related changes in the liver start activity that causes the tiny blood vessels in the lungs to dilate and undergo other changes. The result is that blood can't efficiently exchange gases. Red blood cells release carbon dioxide and pick up oxygen as they should.

Risk factors

Not all cases of advanced liver disease lead to hepatopulmonary syndrome. It's not clear why some people with advanced liver disease develop the condition.

Genes with certain changes may increase the risk of getting hepatopulmonary syndrome.