Stroke in Dogs

The onset of acute neurological signs can indicate a cerebrovascular accident. The severity of the signs will depend upon the region of the brain where the abnormality occurred, and how long the brain was deprived of the vital oxygen and blood supply.

• Loss of balance or falling
• Circling or weaving
• Loss of bladder or bowel control
• Paresis (weakness of voluntary movements)
• Loss of vision
• Head tilt
• Ataxia (inability to control movements)
• Change in behavior (for example, a calm dog becomes aggressive)
• Inability to recognize owner
• Seizure
• Sudden collapse

Types

The occurrence of a stroke is broken down into two types.

• Ischemic
• There is lack of blood flow to the brain
• It is the most common type of stroke to affect dogs
• A narrowing of the artery is called thrombosis
• A clogging of the artery by material from another location is called embolism
• Hemorrhagic
• There is a presence of too much blood
• Occurs with a broken blood vessel
• Blood between the brain and skull is a subdural hemorrhage
• Blood leaking within the brain in an intraparenchymal hemorrhage

It should be noted that when symptoms of a cerebrovascular accident resolve within 24 hours, it is considered a TIA (transient ischemic attack).

There are many predisposing conditions that your furry family member can have that may lead to a stroke. Several are listed here.

• Thyroid gland abnormalities
• Infection in the central nervous system
• Cushing’s disease (hyperadrenocorticism)
• High blood pressure (hypertension)
• Protein-losing nephropathy
• Lungworm
• Head trauma
• Heart attack
• Hyperlipidemia (high concentration of fats or lipids in blood)
• Intravascular cancers
• Abnormal development of blood vessels
• Inflammation in blood vessels or arteries
• Ingestion of rodent poisoning
• Increased blood viscosity (thickening of blood)
• Kidney, liver, or heart disease
• Clogging of an artery (such as by fat, tumor, or parasites)
• Congenital clogging disease

If your dog is showing the neurological signs consistent with a cerebrovascular accident, do not delay in bringing him to the clinic. The veterinarian team will be ready to definitively diagnose the problem and do everything they can to calm your pet, and make him more comfortable. A big part of the diagnosis will be determining the underlying cause of the stroke.

The veterinarian may begin the exam with the following questions.

• How long have you noticed a change in your dog’s behavior?
• Did the symptoms come on in an acute fashion, or gradually become more noticeable or intense with time?
• Has your pet been ill recently?
• Is your dog on any medication?
• Is is possible that your dog could have been exposed to rodent poisoning?

The best way to determine if a stroke has taken place is by magnetic resonance imaging (MRI). Your canine companion will need to be put under general anesthetic in order to be sure of good imaging results. The MRI is the leading diagnostic tool because the veterinary specialist will be able to visualise lesions that may be present as the result of a stroke.

The veterinarian may choose to do testing before the MRI to rule out disease, or to pinpoint the cause for the stroke occurrence.

• Also under anesthetic, a spinal tap could be done to rule out diseases that present similarly to a stroke
• Retinal exams to check for instances like optic disc swelling, consistent with intracranial pressure
• Endocrine testing to look for illnesses like diabetes
• Thyroid hormone analysis
• Complete blood count and serum chemistry panel
• Blood pressure
• Urinalysis to check urine creatinine protein ratio
• Clotting studies
• Radiograph (thoracic), CT scan or ultrasound (abdominal) to look for masses, lesions or neoplasia

In the case of a severe stroke victim, the treatment will involve hospitalization. The veterinarian will take the best approach available in the case of a cerebrovascular accident, which will include oxygen support and intravenous therapy to reduce brain swelling. Bringing your pet back to his previous state, or as close as is possible, will be the goal. Stabilising the systems of the body is very important.

Your pet (especially if he is a large breed) may need to stay in the clinic as advised by the veterinary care team, because if the dog is not yet mobile, he will need frequent turning and possible urinary catheterization. Physical therapy could be done during the hospital stay also, to help increase mobility and keep the limbs from becoming stiff.

When the veterinarian feels that your dog is ready to leave the clinic, she will advise you about the home care.

A change in diet may be in order, based on whether there are any underlying conditions. A diet sufficient in essential fatty acids and Omega 3 is thought to be beneficial to dogs who have had a stroke.

As your beloved canine companion recovers, you will need to be in communication with the veterinary care team who will want to be kept well informed on the progression of the recovery. If your dog does not seem to be getting better, or if symptoms are worsening, the veterinarian may want to pursue further testing.

If your dog is recumbent (lying down because he is unable yet to walk or move around), you will need to watch and listen for aspiration pneumonia, one of the greatest risks to dogs who have had a stroke. Signs you may see that will indicate this are coughing, difficulty swallowing, rapid breathing, or difficulty in taking a breath. If you are concerned about your pet’s medical condition, do not hesitate to take him back to the clinic.

The prognosis for stroke in dogs will depend on the severity of the cerebrovascular accident. Patience, reasonable expectations, and consistent care will be necessary. Your pet may have a change in personality, and less mobility or ability to keep up his usual level of activity, but he can still have a good quality of life with your help.