Cyanosis in Dogs

Cyanosis (Blue Coloration) in Dogs

By: Dr. Arnold Plotnick

Section: Veterinary Care In-depth

Diagnosis In-depth

  • Arterial blood gas measurement. Arterial blood gas (ABG) is the "gold standard" for evaluating a cyanotic patient. The test involves obtaining an arterial blood sample. For maximal diagnostic value, the ABG should be evaluated while the animal is receiving supplemental 100 percent oxygen. The response to supplemental oxygen can be used to help rule in or rule out certain causes of cyanosis. For example, if there is peripheral cyanosis due to obstruction of blood flow to one or two limbs, giving supplemental oxygen does not raise the amount of oxygen in the arterial blood, and does not resolve the cyanosis.

    However, if the cyanosis is due to disease of the lungs (edema, infection), hypoventilation, or ventilation/perfusion mismatch, giving supplemental oxygen will raise the amount of oxygen in the arterial blood, and the cyanosis should resolve.
    Giving supplemental oxygen to animals who are cyanotic because of an abnormal form of hemoglobin (such as methemoglobin) will not be helpful, because methemoglobin cannot bind oxygen, regardless of how enriched the oxygen supply is.

  • Pulse oximetry. Pulse oximetry is readily available to most practitioners nowadays. It is a noninvasive way to get an idea of the amount of oxygen in the bloodstream. A probe is applied to a fold of skin in the axillary (armpit) or inguinal (groin) area, or the lip or tongue in an anesthetized animal. The major advantage of pulse oximetry is that you get a continuous reading, allowing sequential monitoring in response to supplemental oxygen.

  • Further diagnostic tests. Depending on the cause of the cyanosis, further diagnostic tests may be warranted. For example, if cardiac abnormalities are the cause of the cyanosis, cardiac ultrasound, electrocardiography, or angiocardiography may be necessary. If respiratory diseases are the cause of the cyanosis, various diagnostic tests such as thoracocentesis (removal of fluid or air from the chest cavity), a transtracheal wash, complete blood count, chemistry panel, urinalysis, chest X-rays, thoracic ultrasound, and fecal analysis may be warranted.

     
    Printable Version
     
    Have a Pet Question?
    Send Your Pet Question to Dr. Jon
    and His Staff of Veterinarians Ask Dr. Jon
    Dr. Jon's Newsletter
    Yes! Send Me the Latest Health Information, Pet Tips, Pet Stories and more...
     
     

    Related Articles

    • 1 Congestive Heart Failure in Dogs

      Heart failure is a condition, caused by an abnormality in the structure or the function of the heart, in which it is unable to pump normal quantities of blood to the tissues of the body.

      Read MoreRead More
    • 2 Chronic Coughing in Dogs

      Coughing, a common protective reflex that clears secretions or foreign matter from the throat, voice box, windpipe or airways, and protects the lungs from aspiration, affects the respiratory system by...

      Read MoreRead More
    • 3 Dilated Cardiomyopathy in Dogs (DCM)

      Dilated cardiomyopathy (DCM) is a disease characterized by dilation or enlargement of the heart chambers and markedly reduced contraction. DCM is very common in dogs, representing the most common reason...

      Read MoreRead More
    • 4 Syncope (Fainting) in Dogs

      Syncope is the term used to describe fainting, which is a brief period of unconsciousness due to cerebral anemia and may last from seconds to minutes. Most fainting “spells” are due to low blood pressure...

      Read MoreRead More
    • Related Articles
    • 1Chronic Coughing in Dogs

      Coughing, a common protective reflex that clears secretions or foreign matter from the throat, voice box, windpipe or airways, and protects the lungs from aspiration, affects the respiratory system by...

      Read MoreRead More
    • 2Dilated Cardiomyopathy in Dogs (DCM)

      Dilated cardiomyopathy (DCM) is a disease characterized by dilation or enlargement of the heart chambers and markedly reduced contraction. DCM is very common in dogs, representing the most common reason...

      Read MoreRead More
    • 3Congestive Heart Failure in Dogs

      Heart failure is a condition, caused by an abnormality in the structure or the function of the heart, in which it is unable to pump normal quantities of blood to the tissues of the body.

      Read MoreRead More
    • 4Syncope (Fainting) in Dogs

      Syncope is the term used to describe fainting, which is a brief period of unconsciousness due to cerebral anemia and may last from seconds to minutes. Most fainting “spells” are due to low blood pressure...

      Read MoreRead More
     

    Over 10,000 Veterinarian Approved Articles

    Dogs & Puppies
    Cats
    Related Articles
    • 1Chronic Coughing in Dogs

      Coughing, a common protective reflex that clears secretions or foreign matter from the throat, voice box, windpipe or airways, and protects the lungs from aspiration, affects the respiratory system by...

      Read MoreRead More
    • 2Dilated Cardiomyopathy in Dogs (DCM)

      Dilated cardiomyopathy (DCM) is a disease characterized by dilation or enlargement of the heart chambers and markedly reduced contraction. DCM is very common in dogs, representing the most common reason...

      Read MoreRead More
    • 3Congestive Heart Failure in Dogs

      Heart failure is a condition, caused by an abnormality in the structure or the function of the heart, in which it is unable to pump normal quantities of blood to the tissues of the body.

      Read MoreRead More
    • 4Syncope (Fainting) in Dogs

      Syncope is the term used to describe fainting, which is a brief period of unconsciousness due to cerebral anemia and may last from seconds to minutes. Most fainting “spells” are due to low blood pressure...

      Read MoreRead More