Shock Due to Heart Failure in Dogs

When the dog’s body has an abnormally low or insufficient circulation to supply the body with proper flow of blood, shock occurs. The poor output by the cardiovascular system, even though there is enough blood is considered a form of heart failure. The body’s tissue requires a specific amount of oxygen and other nutrients and this condition is when those requirements are certainly not met.

The heart is a vital pump, and it must function properly for the dog to be healthy. There are many reasons why cardiogenic shock may occur, and the medical professional will find the source once the dog is treated for the results of the shock, which are inadequate oxygen in the bodily tissues and lack of proper distribution of blood throughout the body. In many cases of cardiogenic shock, the condition is due to an underlying illness, or secondary condition. Also, there are several different types of shock that may be present, and the veterinarian will have to swiftly assess the dog when he comes in. The various types of the shock do present similar symptoms.

Shock due to heart failure in dogs occurs when there is not sufficient circulation of blood, and when the cardiovascular system has abnormally low output.

There are many symptoms of cardiogenic shock, and many of these symptoms are quite noticeable and can be severe. If you notice the dog exhibiting any of these symptoms, please seek a veterinarian’s attentions. Symptoms of cardiogenic shock include:

• Intolerance to exercise
• Weakness
• Lethargy
• Collapse
• Anxiety or seemingly stressed
• Disorientation
• Depression
• Pale mucous membranes
• Weakened pulse
• Crackling chest
• Cough or wheeziness

Types

There are four different types of shock due to heart failure in dogs. With all types of heart failure shock, the cells must go through the change from glucose to lactate (production of lactate acid) to use as a short-term energy source when oxygen levels are low. Types of shock due to heart failure in dogs are:

• Cardiogenic
• Distributive
• Hypoxic
• Metabolic

When the heart has a poor cardiac output, there are several different reasons for this condition. Causes of shock due to heart failure in dogs are:

• Dilated heart muscle
• Insufficient valves
• Pericardial constriction
• Toxins or drugs
• Stenosis
• Pericardial fibrosis
• Sepsis
• Abnormal amount of blood phosphorus
• Blood clot
• Gas in chest cavity

There are many causes of cardiogenic shock, and the veterinarian will need to use differential diagnosis in some cases. The dog will need to be stabilized at first and then the medical professional will find out the root of the cause of cardiac shock. In addition to the following tests, the veterinarian will do routine tests, such as blood work, urinalysis, biochemistry profile, and any other routine tests necessary.

The veterinarian will do many tests, which will include blood pressure and electrocardiography to listen for any arrhythmias and to further look at the heart muscle, valves, and the compression of the organ. The doctor will also check the dog’s pulse rate and measure the saturation of oxygen in the blood and tissues. He will also check the dog’s blood gas for pH amounts and metabolic acidosis to determine the blood acid-base amounts.

With cardiogenic shock, more than likely the dog will be placed in intensive care in the animal hospital until his body is stabilized and he begins to respond positively to treatment. More intense treatment will be focused on the underlying disorder that led to the cardiogenic shock. Treatment options include:

Drainage

Any fluid that has built up around the pericardium will be drained to help the ease the compression in the heart lining.

Fluid Therapy

Once the cardiac function begins to improve, fluid therapy will be given by positive inotropes to strengthen the heartbeat. 

Vasodilators

Vasodilators are used to help widen the blood vessels to aid in proper heart function and blood flow. The cells within the vessel walls are relaxed to prevent tightening of the muscles and narrowing of the walls.

Oxygen Therapy

When the blood flow is decreased as a result of cardiogenic shock, there is not a sufficient amount of oxygen to reach the tissues. The dog that is beginning to heal from cardiogenic shock will require oxygen therapy. This may be given through a mask, within a cage, or through a nasal tube. 

Monitoring

An electrocardiogram will be set up to monitor the electrical currents of the muscle of the heart. This will also measure the pressure and blood pressure to be sure any treatment for the underlying disorder is working.

In terms of prognosis, it depends on the condition and age of the dog, the severity of the condition, and the underlying cause. For many dogs, they can continue to live normal lives if the condition is monitored and the treatment is effective for the primary cause.

It is important to follow the veterinarian’s guidelines for after care, and to keep each appointment for regular check-ups. During each visit, the doctor will take a close look at the dog’s heart and cardiovascular system, and possibly perform any routine tests, if necessary to see the progress your companion is making. With a lot of love and a watchful eye on your companion’s symptoms, your dog will remain content and relaxed.