Cyanosis (Blue Coloration) in Dogs

Cyanosis is a bluish or purplish coloration imparted to the skin or mucous membranes due to excessive amounts of poorly oxygenated hemoglobin in the circulation. The causes include certain congenital heart diseases, various respiratory diseases, and exposure to certain chemicals that result in the creation of some abnormal forms of hemoglobin which are incapable of binding oxygen properly.

Cyanosis in pets is usually an alarming clinical symptom for pet owners and for veterinarians. 

What to Watch For

Purplish/bluish coloration of the tongue, gums, lips, and areas of the skin in which the blood vessels are superficial

Possible purplish/bluish coloration of the foot pads

Diagnosis

Arterial blood gas measurement

Pulse oximetry

Other specific tests, depending on the disorder that is causing the cyanosis

Treatment

Therapy of cyanosis will depend on what is causing the condition. 

Congenital heart disease. If the condition is caused by congenital heart disease, the treatment is surgery.

Chemical. If a chemical has affected the hemoglobin in such a way that it cannot carry oxygen properly, for example, by inducing the formation of methemoglobin, an abnormal type of hemoglobin that cannot carry oxygen, the treatment involves: elimination of the cause, limiting any tissue injury due to poor oxygenation, and administration of medication (methylene blue; N-acetylcysteine) if necessary.

Respiratory Disorder. If a respiratory disorder is the cause of the cyanosis, the underlying respiratory disease must be treated with antibiotics if pneumonia or chronic bronchitis is present, diuretics if fluid is building up in the lungs, thoracocentesis, which is removal of fluid or air from the chest cavity if fluid or air is causing the cyanosis, or supplemental oxygen as necessary.

Emergency treatment involves making sure that the airway is unobstructed and providing oxygen by: face mask, nasal oxygen tube, oxygen cage, intubation of the trachea.

Home Care

There is no specific home care for cyanosis. Animals who are suspected to be cyanotic should be evaluated by a veterinarian immediately. Depending on the cause of the cyanosis, your veterinarian will make specific recommendations as warranted.