Stupor and Coma in Cats

Marginal Consciousness and Complete Unconsciousness in Cats

The term stupor is used if an animal is unconscious but can be aroused with very strong external stimulus, whereas a patient that is in a coma will remain unconscious even if the same level of external stimulus is applied. Cats of any age, breed, or gender are susceptible to this condition.

Symptoms and Types

The symptoms are highly variable depending on the primary disease that has led to the loss of consciousness, whether it is temporary, as with stupor, or long lasting, as with coma.

The major symptom is varying levels of unconsciousness, with the degree of consciousness depending on the nature and severity of the underlying disease.

Causes

• Drugs which lead to loss of consciousness
• Abnormally low blood glucose levels (hypoglycemia)
• Abnormally high blood glucose levels (hyperglycemia)
• Abnormally high levels of sodium in the blood (hypernatremia)
• Abnormally low levels of sodium in the blood (hyponatremia)
• Low blood pressure
• Kidney failure
• Primary brain disease
• Trauma, especially to the head and brain
• Infections (viral, bacterial, parasitic, fungal)
• Unknown cause (idiopathic)
• Immune-mediated (immune system overreacts or attacks the body)
• Chemical or drug toxicity

Diagnosis

Both of these conditions are health emergencies and will require that you take your cat to a veterinarian immediately for treatment. You will need to give a thorough history of your cat’s health including a background history of symptoms. After taking a detailed history, your veterinarian will conduct a complete physical examination on your cat. Laboratory tests will include a complete blood count (CBC), biochemistry profile, and urinalysis. There are a number of diseases/conditions that can lead to these symptoms and laboratory tests will show any abnormalities that could be related to an underlying disease.

For example, in case of lead toxicity, abnormal red blood cells will usually appear in the complete blood count tests. In cases with infection and inflammation, an increased number of white blood cells, cells that multiply in response to infection and trauma, will be seen.

The biochemistry profile may indicate lower or higher than normal values of glucose in the blood, higher than normal levels of sodium in blood, and accumulation in the blood of nitrogenous waste products (urea), which are usually excreted out of the body through the urine.

The urinalysis may indicate high levels of glucose in the urine, a common sign in diabetes mellitus; abnormally high levels of proteins that are normally not present in the urine, such as with immune-mediated diseases; and abnormal crystals in the urine, such as what is seen in the presence of liver disease or ethylene glycol toxicity.

If the cause is not so readily apparent, more specific testing may be required to diagnose the underlying disease. Infections are one of the most important risk factors for developing stupor or coma, especially in case s of untreated infections. Your veterinarian will test for various infections that are common in cats and that are known to cause serious symptoms like stupor or coma.

Bleeding inside the brain is also a possible cause of stupor or coma, and your veterinarian can order tests to measure the normal blood clotting mechanisms in your cat's system. Besides laboratory analyses and tests, visual diagnostics can also be used to great advantage. X-rays of the abdomen and chest can be used to confirm if there is a diseased condition present in these areas, or whether there have been resultant changes in the organs. Similarly, head X-rays can be used to evaluate whether an unknown injury has occurred, whether there is fracture, inflammation or any other injury that might be affecting the brain's ability to function normally.

Your doctor will need to determine which machine will give the clearest image of the head. In some cases, X-ray may not be enough, and a computed tomography (CT) scan or magnetic resonance imaging (MRI) will be needed to diagnose the presence of hemorrhage, fracture, mass, accumulation of fluid, or a penetrating foreign body in the skull and/or brain. An electrocardiogram (ECG) may also be used to evaluate cardiac functions as cardiac diseases and abnormalities can also lead to stupor or coma.

Treatment

This is a health emergency and you will need to immediately take your cat to a veterinary hospital. The major goal of emergency treatment is to save the life of the patient, and will be started as quickly as possible. Along with the emergency treatment, efforts will be made to diagnose the underlying cause in order to treat it. Oxygen supplementation is started as soon as the patient is received at the hospital in a condition of stupor or coma.

If there is excessive fluid loss, small amounts of intravenous fluids will be given to counter the fluid deficits. Large amount of fluids are usually avoided as this practice can cause further brain swelling in patients suffering from brain edema (swelling).

In case of head injuries, the cat's head will be kept elevated on a level above the rest of the body to avoid further swelling of the brain. If seizures are also a problem, medications will be given to control the seizures because these can also lead to further swelling of the brain. To overcome the brain swelling, drugs are given to promote urination in order to remove the fluid accumulated within brain. In serious head injuries or in cases with serious brain swelling, surgery is usually required to remove the fluid from the brain to reduce the swelling in order to save the life of the patient. In cases of infection, antibiotics can be given to control the symptoms related to the infection and to eliminate it from the body.

Living and Management

Stupor and coma are emergencies needing intensive hospital care and treatment. The overall prognosis largely depends on the treatment of the underlying disease or condition. Special attention needs to be paid to nutrition since these patients are not able to eat, especially during the time when they are partially or fully unconscious. Even after regaining consciousness, these patients need to be monitored closely for future episodes of similar symptoms.

At home, proper rest and isolation should be provided to your cat until it has fully recovered. You will need to set up a place in the house where your cat can rest comfortably and quietly, away from other pets, active children, and busy entryways. To make the recovery period easier for your cat, place the feeding dishes and litter box close to where your cat is resting so that it does not need to make a lot of effort. While you will want to give your cat as much peace as possible, you will need to check in on your cat frequently, observing its breathing pattern and rate.

Medications and nutrition need to be given on time, as scheduled. If your cat is too weak to eat a sufficient amount of food on its own, you will need to assist it in eating, either with a feeding syringe or tube. Your veterinarian will advise you on the method and how to go about doing it.

If you see any untoward symptoms, immediately consult your veterinarian.