Cyanosis in Dogs

Jamie Lovejoy, DVM
By Jamie Lovejoy, DVM on Dec. 20, 2023
white fluffy dog at vet getting blood drawn

In This Article


What Is Cyanosis in Dogs?

Cyanosis is the bluish-purple tinge that blood acquires when it’s not carrying enough oxygen. In dogs, this color change is usually easiest to see on their tongue, gums, or inner ears, where the blood vessels are very superficial and the haircoat is thinnest.

Cyanosis is usually due to the lungs or the circulatory system not working properly.

If you are concerned that your dog is cyanotic, it’s a medical emergency that requires immediate stabilization at the nearest emergency vet clinic. 

Try to get your dog to an emergency veterinary hospital or a hospital with an intensive care unit for the most complete care options. If that type of facility is more than 30 minutes away, the closest vet with oxygen will be the best place to start.

Symptoms of Cyanosis in Dogs

Cyanosis is often accompanied by other symptoms of respiratory or cardiac stress such as:

  • Heavy panting

  • Coughing

  • Visible abdominal muscle movement while breathing

  • Inability to rise

  • Collapse

  • Pacing and agitation

Causes of Cyanosis in Dogs

Cyanosis can be classified as central or peripheral.

Central Cyanosis in Dogs

In central cyanosis, the lungs are unable to get oxygen to the bloodstream. This can be due to obstruction of the larger airways (e.g., choking, asthma, or bronchitis) or due to a buildup of fluid or tissue in the lungs from conditions like heart disease, pneumonia, or cancer.

Fluid may also build up around the lungs in these conditions, rendering them unable to expand enough to bring oxygen to the blood. Brachycephalic (short-nosed) dogs such as American, English, and French Bulldogs, Pugs, and Boston Terriers are very prone to central cyanosis due to their narrow airways and sensitivity to heat.

Peripheral Cyanosis in Dogs

In peripheral cyanosis, the lungs get oxygen to the blood but the circulatory system has difficulty bringing this oxygenated blood to the rest of the body.

Causes of peripheral cyanosis include heart failure, low blood pressure, or shock from infection or allergic reactions, blood loss (internal or external), and blood clots (thrombosis). Cancer and autoimmune disease can affect production of red blood cells in the bone marrow, which may decrease your dog’s oxygen-carrying capacity.

How Veterinarians Diagnose Cyanosis in Dogs

Cyanosis will be easily observed by your vet during a physical exam. Stabilization and diagnostics will be recommended based on the symptoms your dog has and the equipment the vet has available. If your dog is struggling to breathe, they may require sedation and intubation, ventilation, or a tracheotomy to assist in lung function before other diagnostics can be safely completed.

If the upper airways is clear, your vet may elect to place your dog in a special enclosure with higher oxygen levels to allow them to get more oxygen without sedation.

Other diagnostics may include:

  • A complete blood count (CBC) will show if your dog has appropriate numbers of circulating red blood cells and hemoglobin levels. It can also look for platelet issues that can lead to bleeding disorders.

  • Blood chemistry can help evaluate for evidence of organ failure from lack of oxygen or concurrent illness, which may affect what treatments are available.

  • A blood gas analysis, which can reveal how much oxygen is in the blood and how severe the body’s response to the lack of oxygen is.

  • X-rays of their chest, once your dog is stable, may be taken to look for structural changes that may affect heart and lung function.

  • If heart disease is suspected, an ultrasound of the heart (echocardiogram) and evaluation of the heartbeat (EKG) may be recommended.

  • Radiographs of the abdomen may be useful if internal bleeding or abdominal masses are suspected as the cause of cyanosis.

  • Rarer cancers and metabolic diseases that affect the airways may require advanced imaging such as a CT scan or MRI to diagnose them and help your vet determine why your dog is cyanotic, but this is uncommon.

Treatment of Cyanosis in Dogs

Depending on the cause and how quickly care is sought and administered, dogs can survive cyanosis. Potentially treatable conditions include airway obstruction from foreign objects or brachycephalic airway syndrome, toxin exposure, anaphylaxis, and trauma—though there may be a long road to recovery.

Blood oxygenation is extremely important to a dog’s normal body function, and unfortunately, death can occur very quickly in some cases.

In other cases, pups may be able to regain the ability to oxygenate successfully in the hospital, but the underlying condition may not be curable, and they cannot be easily managed at home. Many forms of cancer and severe heart disease have poor long-term outcomes despite early and aggressive care.

Recovery and Management of Cyanosis in Dogs

Recovery from conditions causing cyanosis usually requires hospitalization. Veterinary hospitals can provide patients with highly oxygenated breathing air, improve circulation with IV fluids, and even help the lungs expand through ventilation when they are not breathing normally on their own.

Dogs not stable with normal air oxygen levels cannot safely be sent home. As such, some dogs may not recover.

The prognosis of a dog who does survive cyanosis and is discharged from the hospital will vary depending on their underlying condition.

Your vet will discuss with you the potential long-term outcomes for your dog. Some causes of cyanosis (especially ones that can be treated surgically) will never recur, while others will have to be carefully managed with medications to prevent another episode.

Prevention of Cyanosis in Dogs

The best way to try to prevent cyanosis in your dog is to be consistent with annual checkups and preventative care:

  • Heartworm prevention and routine fecal testing can help find and eliminate parasitic causes of heart and lung disease.

  • Pet parents of brachycephalic dogs should discuss whether airway surgery is needed for their pup.

  • Annual bloodwork can help monitor changes in red blood cell and platelet numbers.

  • Dogs with heart murmurs should have a workup with a veterinary cardiologist before there is an emergency, if possible.

Additional tips include:

  • Coughing dogs should be evaluated promptly with chest X-rays.

  • Avoid dog toys that are small enough to enter your dog’s airway.

  • To avoid strangulation, do not leave collars on unattended dogs. Breakaway collars are a great investment if taking your dog’s collar off is not practical. This type of collar is especially important if you have a multi-dog household, as dogs can get their teeth caught on each other’s collars even during monitored play, leading to death or injury.

Cyanosis in Dogs FAQs

Is cyanosis in dogs dangerous?

Yes, if a dog has cyanosis—a bluish tint that can be easiest to see on the tongue, gums, or inner ears—it’s a true medical emergency. The dog needs immediate veterinary care to become stable and to boost the oxygen levels in their blood and tissues.

How can I increase my dog’s oxygen level?

Appropriate therapy of cyanosis requires veterinary intervention and can’t be performed at home. The best thing you can do while in route to an emergency hospital is to keep yourself and your dog as calm as possible, because rapid breathing, panting, and anxiety can worsen oxygen distribution.

Featured Image: RossHelen/iStock via Getty Images Plus

Jamie Lovejoy, DVM


Jamie Lovejoy, DVM


Dr. Jamie Lovejoy graduated from Tufts Cummings School of Veterinary Medicine in 2012 after an undergraduate degree in Marine Biology. ...

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