A stroke, or cerebrovascular accident, occurs when the brain's blood supply is reduced. It's terrifying to think of your poor pup suffering such a traumatic event. However, the good news is dogs tend to recover from strokes better than their human masters. Getting a dog to the vet at the first hint of a stroke improves his chances of a strong recovery.
Stroke: Blood and Oxygen Flow Interrupted
There are two types of strokes, the hemorrhagic type, caused by a burst blood vessel, and the ischemic stroke, when there's a sudden lack of blood supplied to the brain, which is more common in dogs. When you consider that the brain is the body's communication center, the impact of the loss of blood and oxygen makes sense. The loss of function will show differently based on what part of the brain is affected. For example, if the midbrain region is affected, head-tilting, crossed eyes or back and forth eye movements are normal. If the cerebellum region is damaged, a drunken gait and rigid neck and body may be seen in addition to head-tiling and eye movements. The vet will consider your dog's behavior when he makes his diagnosis.
Diagnosing a Stroke and its Cause
Other conditions such as head trauma, cancer, poisoning, inflammation or infection also present sudden neurological symptoms, so the vet will rely on tests to confirm a diagnosis of a stroke. The vet will do the standard blood and urine tests, as well as measure blood pressure and review your dog's medical history. An MRI or a CT is necessary to find blood clots, bleeding or damaged areas of the brain. The tests are conducted while the dog's under anesthesia, also allowing the vet to draw a spinal fluid sample, to rule out other diseases. The visual evidence from the MRI, combined with the lab work, allows the vet to confirm a stroke diagnosis, as well as helps to determine its cause. Once the diagnosis is confirmed, supportive care begins and the vet works to confirm the cause of the stroke.
Recover and Treat the Cause
Once a stroke has occurred, there's nothing to be done to repair the brain's damage. However, supportive care can make the difference in long-term recovery, so it's important to get veterinary attention quickly. Depending on the dog's condition, he may have a feeding tube and supplemental oxygen. Occasionally a ventilator is necessary to ensure proper respiratory function. Fluid therapy and medication for high blood pressure and to minimize pressure in the brain is often part of the recovery effort. If the vet can determine what caused the stroke, he can work towards preventing future strokes and incorporate treating the root cause of the stroke into the recovery effort. Heart, kidney and thyroid disease, heartworms and Cushing's disease are all factors contributing to increased risk of stroke.
Dogs tend to bounce back from strokes fairly successfully if they survive the first three or four days after the event. Some dogs have no lasting effects while other dogs endure permanent disabilities. Depending on how the dog is affected, physical therapy and carts may be necessary. If the dog has any paralysis, care must be taken so he doesn't develop bed sores and skin lesions from dragging himself. Some vets may prescribe aspirin to protect against the possibilities of future strokes, however there haven't been any studies to indicate this course of action is effective in dogs as it is in humans. Ask your vet whether aspirin is right for your dog. Treating the root cause of the stroke minimizes the possibility of future events.