Primary alveolar hypoventilation is a rare disorder of unknown cause. It leads to inadequate breathing despite the lungs and airways being normal.

The cause of this disease is unknown. Current research is looking at how the brain of these patients may be less responsive to carbon dioxide.

The condition is usually worse during sleep, and periods of apnea (where the breathing stops) are usually present. Patients with this disease are extremely sensitive to even small doses of sedatives or narcotics, which can make their inadequate breathing much worse. The disease primarily affects men 20 to 50 years old. It can also be present in male children.

This condition is commonly seen in those with obesity hypoventilation syndrome.

• Lethargy
• Fatigue
• Morning headache
• Daytime somnolence
• Swelling of the ankles
• Bluish coloration of the skin caused by lack of oxygen
• Awakening from sleep unrested
• Awakening many times at night

• Pulmonary function tests
• Blood gases
• Chest x-ray
• Overnight oximetry (a test to measure oxygen levels during the night)
• Sleep study (polysomnography)

This disease may also alter the results of the following tests:

• Serum bicarbonate
• Hematocrit

Medications that stimulate the respiratory system may be used. Mechanical devices that assist breathing, particularly at night, may be helpful in some patients. Oxygen therapy may be helpful in some patients, but may produce worse night symptoms in others.

Response to treatment varies.

A possible complication is cor pulmonale (right-sided heart failure).

Call for an appointment with your health care provider if symptoms of this disorder develop. Bluish skin (cyanosis) may indicate an urgent need for treatment.

There is no known prevention.