Acidosis - respiratory

Definition

Respiratory acidosis is a condition that occurs when the lungs cannot remove all of the carbon dioxide produced by the body. This creates a disruption in the body's acid-base balance. Body fluids become excessively acidic.

Alternative Names

Causes

Respiratory acidosis can result from lung diseases such as chronic obstructive pulmonary disease (COPD) and severe asthma

Other conditions that may lead to respiratory acidosis include:

• Obesity hypoventilation syndrome  
• Excessive fatigue or weakness of the rib cage muscles
• Severe deformities of the spine and rib cage such as severe scoliosis
• Airway obstruction

Chronic respiratory acidosis occurs over a long period of time. This leads to a stable situation. This is because the kidneys increase chemicals that help restore the body's acid-base balance.

Acute respiratory acidosis is a severe condition in which the carbon dioxide builds up very quickly.

Symptoms

Symptoms may include shortness of breath, easy fatigue, chronic cough, or wheezing.

When respiratory acidosis becomes severe, confusion, irritability, or lethargy may occur.

Exams and Tests

A chest x-ray or CT scan may be done to diagnose possible lung disease.  

Pulmonary function tests   may help diagnose lung disease.

Arterial blood gases can tell how bad the respiratory acidosis is, and may detect abnormal oxygen levels.

Treatment

Treatment is aimed at the underlying lung disease, and may include:

• Methods to stop smoking (this is extremely important)
• Bronchodilator drugs to reverse some airway obstruction
• Oxygen if the blood oxygen level is low
• Non-invasive positive-pressure ventilation or mechanical ventilation if the respiratory acidosis is severe

Outlook (Prognosis)

How well a patient does depends on the disease causing the respiratory acidosis.

Possible Complications

• Respiratory failure
• Poor organ function
• Shock

When to Contact a Medical Professional

Severe respiratory acidosis is a medical emergency. Seek immediate medical help if you have symptoms of this condition.

Call your health care provider if you have symptoms of lung disease.

Prevention

Do not smoke. Smoking leads to the development of many severe lung diseases that can lead to respiratory acidosis.

Losing weight may help prevent obesity hypoventilation syndrome.

Murray J, Nadel J. Textbook of Respiratory Medicine. 3rd ed. Philadelphia, Pa: WB Saunders; 2000: 191-192. 

Marx J. Rosen's Emergency Medicine: Concepts and Clinical Practice. 5th ed. St. Louis, Mo: Mosby; 2002:1716-1717.

Ford MD, Clinical Toxicology. 1st ed. Philadelphia, Pa: WB Saunders; 2001:92.