Low Blood Oxygen in Dogs

Just like people, the oxygen in the blood has to be at a certain level to sustain life in dogs. Without the proper amount of oxygen in your dog’s blood, The amount needed for the health and performance of the dog’s vital organs is more than 70mm, but in hypoxemia, the blood gas is usually lower than 60mm hemoglobin. Another way to determine hypoxemia is if the dog has an oxygen saturation level of less than 90%. Hypoxemia is a life-threatening emergency situation which will result in death if not treated right away. If your dog has symptoms of not being able to breathe, you should take him to the veterinary hospital or clinic immediately.

Low blood oxygen, or hypoxemia, is a serious condition that is described as a decreased and insufficient amount of arterial blood needed for the dog’s body systems. If hypoxemia is left untreated, even for a short period, the internal organs will start to malfunction, so immediate medical attention is needed.

If your dog is suffering from hypoxemia, you should notice right away because he will obviously be in distress and gasping for breath. There may be a blue tint to your dog’s skin as well. If your dog is alone at the time (common with outdoor dogs) and nobody notices the symptoms, it is likely to be fatal due to the permanent damage to the brain, lungs, and other vital organs from loss of oxygen. It is good to check on your outside dog often or bring him indoors if you are unable to do so. Some of the most common symptoms in hypoxemia are:

• Shortness of breath 
• Gagging or gasping
• Difficult and rapid breathing
• Excessive coughing and gagging
• Blue or purple tint to the skin (cyanosis)
• Fast heart rate
• Pain when breathing
• Frothy discharge from nose and mouth
• Weakness
• Refusing to exercise or walk
• Loss of appetite and weight loss
• Fainting
• Collapse
• Seizure
• Death

The cause of hypoxemia is a lower than normal oxygen level in the blood, but there are many causes of the low oxygen levels. There are four general causes for the drop in the oxygen level, but each cause has its own reasons:

Hypoventilation

• Neuromuscular disease
• Cervical spinal cord disease
• Obstruction or disease of the airway
• Heavy sedation
• Severe respiratory muscle fatigue

V/Q Mismatch

• Pneumonia
• Pulmonary edema
• Pulmonary hemorrhage
• Pulmonary neoplasia
• Pulmonary embolism

Intrapulmonary Shunt

• Lung collapse
• Lung disease

Diffusion Impairment

• Pulmonary fibrosis

Other

• Injury
• Heart disease
• Severe anemia

Since you may be at an emergency animal hospital or clinic instead of your regular veterinarian, it is important to bring information about your dog’s medical history including vaccination records, illnesses, injuries, abnormal behavior, and changes in appetite. You will also need to give the veterinarian detailed information on the symptoms you noticed and what led up to the incident. It is also a good idea to call your regular veterinarian’s office and let them know what is going on and where you are taking your dog. Be sure to give the animal hospital or clinic your veterinarian’s name and number so they can contact their office and forward any important information.

The veterinarian at the hospital will first get your dog stabilized by providing oxygen therapy and fluids before doing a physical examination. During the exam, they will be checking heart rate, blood pressure, body temperature, heart rate, and oxygen saturation level.

Some blood tests will need to be done, such as complete blood count (CBC), blood gases, chemical profile, and glucose level. Other tests the veterinarian will likely perform are radiographs (x-rays) of the chest and abdomen, echocardiogram (EKG), endoscopy,  and a fine needle biopsy of any fluid in the lungs and chest cavity if necessary. If further details are needed, the veterinarian will order an MRI, CT scan, or ultrasound.

The treatment depends on the final diagnosis, but the initial care will be oxygen therapy by mask, enclosed oxygen cage, or nasal cannula. 

IV medication (i.e. antibiotics, bronchodilators, antihistamines, diuretics, mucus thinning medication), and draining of excess fluid in the lungs or chest cavity will also be provided during oxygen therapy if needed. Your dog will be hospitalized until stable, and then can go home if the underlying cause is found and treated.

Once your dog is home, you will need to continue to provide a comfortable place to rest and recuperate away from other animals and family members that may cause stress or anxiety. It is important to keep your dog calm and quiet during recovery. If the veterinarian sent your dog home with any medication, be sure to follow the instructions and give all of the medication even if it seems like it is not needed after a few days. Failing to finish the medication can cause the illness to return, and it may be worse than the original episode.