Respiratory acidosis
Also known as: Ventilatory failure, Respiratory failure or Acidosis - respiratory
Definition
Respiratory acidosis is a condition that occurs when the lungs cannot remove all of the carbon dioxide the body produces. This disrupts the body's acid-base balance causing body fluids, especially the blood, to become too acidic.
Causes, incidence, and risk factors
Causes of respiratory acidosis include:
- Diseases of the airways (such as asthma and chronic obstructive lung disease), which send air into and out of the lungs
- Diseases of the chest (such as sarcoidosis), which make the lungs less efficient at filling and emptying
- Diseases affecting the nerves and muscles that "signal" the lungs to inflate or deflate
- Drugs that suppress breathing (including powerful pain medicines, such as narcotics, and "downers," such as benzodiazepines), especially when combined with alcohol
- Severe obesity, which restricts how much the lungs can expand
Chronic respiratory acidosis occurs over a long period of time. This leads to a stable situation, because the kidneys increase body chemicals, such as bicarbonate, that help restore the body's acid-base balance.
Acute respiratory acidosis is a severe condition in which carbon dioxide builds up very quickly and before the kidneys can return the body to a state of balance.
Symptoms
Symptoms may include:
- Confusion
- Easy fatigue
- Lethargy
- Shortness of breath
- Sleepiness
Signs and tests
- Arterial blood gas (measures levels of oxygen and carbon dioxide in the blood; in respiratory acidosis, the level of carbon dioxide is too high)
- Chest x-ray
- Pulmonary function test
Treatment
Treatment is aimed at the underlying lung disease, and may include:
- Bronchodilator drugs to reverse some types of airway obstruction
- Noninvasive positive-pressure ventilation (sometimes called CPAP or BiPAP) or mechanical ventilation if needed
- Oxygen if the blood oxygen level is low
- Treatment to stop smoking
Expectations (prognosis)
How well you do depends on the disease causing the respiratory acidosis.
Complications
- Poor organ function
- Respiratory failure
- Shock
Calling your health care provider
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 cause respiratory acidosis.
Losing weight may help prevent respiratory acidosis due to obesity (obesity-hypoventilation syndrome).
Be careful about taking sedating medicines, and never combine these medicines with alcohol.
References
Seifter, JL. Acid base disorders. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier. 2007: chap 119.
See Also: Cystic fibrosis, Clopidogrel (Plavix), Obesity hypoventilation syndrome (OHS), Campylobacter enteritis, Heart disease - risk factors, Short bowel syndrome, Carotid artery surgery, Meckel's diverticulum, Histoplasmosis - chronic pulmonary, Cholangiocarcinoma, Collapsed lung, Pulmonary alveolar proteinosis, Heart bypass surgery, Angina, Blastomycosis, Pulmonary embolus, Atherosclerosis, Angioplasty and stent placement - carotid artery, Asthma, Pneumonia - weakened immune system, Gastrointestinal perforation, Coccidioidomycosis - chronic pulmonary, Drug-induced pulmonary disease, Occupational asthma, Rheumatoid lung disease, Angiodysplasia of the colon, Chronic obstructive pulmonary disease, Pulmonary hypertension, Coccidioidomycosis - acute pulmonary, Heart bypass surgery - minimally invasive, Histoplasmosis - disseminated, Esophageal stricture - benign, Coronary heart disease, Hepatic vein obstruction (Budd-Chiari), Angina - discharge, Esophageal perforation, Breathing difficulty, Coccidioidomycosis - disseminated, Heart attack - discharge, Psittacosis, High blood cholesterol and triglycerides, Hypertension, Acute respiratory distress syndrome, Simple pulmonary eosinophilia, Angioplasty and stent placement - peripheral arteries, Stroke risk factors and prevention, Mitral valve surgery - open, Aortic valve surgery - open, Cardiac ablation procedures , Implantable cardioverter-defibrillator, Mitral valve surgery - minimally invasive, Aortic valve surgery - minimally invasive, Heart pacemaker, and Peripheral artery bypass - leg
Review date: August 8, 2009
Reviewed by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
