Heat Stroke / Hyperthermia and the Heart

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Dao lam gia bao, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons

Hyperthermia (excessive body temperature) or heat stroke can occur in the following situations and conditions:

• ObesityOverweight cats and dogs have a lower ability to regulate their body temperature.

• Obstruction in the upper respiratory tract:

• Laryngeal paralysis (laryngeal paralysis)

• Tracheal collapse (collapse of the trachea)

• Masses or foreign objects obstructing the respiratory tract

• Excessive exercise in hot and humid weather: Occurs during running or intense physical activity.

• Inability to escape from heat source: Being trapped in airless and extremely hot environments such as a vehicle, attic, or basement.

• Past history of hyperthermia/heat strokeCats and dogs that have had heatstroke before are at high risk of having it again.

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There are many direct and indirect connections between heat stroke (hyperthermia) and heart health. Especially in animals with heart disease, heat stroke can lead to more serious complications and fatal outcomes. Here are those links:

1. Increased Heart Load and Risk of Heart Failure

During heat stroke, the body temperature rises excessively and the body activates various defense mechanisms to reduce this temperature. One of these is the dilation of the blood vessels (vasodilation).

• Blood circulation accelerates: The dilation of the veins tries to dissipate heat by allowing more blood to flow to the skin. However, this puts additional strain on the heart, which has to work harder to manage this increased blood flow.

• Heart rate increases: The heart, which has to pump more blood than normal, begins to beat rapidly (tachycardiaThis increase in heart rate causes the heart muscle to consume more oxygen and become tired.

• Risk of heart failure: Animals with heart disease (especially dilated cardiomyopathy – DCM or myxomatous mitral valve disease – MMVD ) have difficulty handling this extra load. This also congestive heart failure (CHF) increases the risk of developing. The heart cannot pump enough blood and this causes fluid to accumulate in the lungs.

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2. Heart Rhythm Disorders (Arrhythmias)

Electrolyte imbalances experienced during heat stroke can disrupt the rhythm of the heartbeat.

• Electrolyte imbalances: During hyperthermia, the animal's body loses excess fluid (even though animals do not have a sweating mechanism, fluid loss occurs through evaporation through respiration and saliva). This situation, sodium (Na+), potassium (K+) and calcium (Ca2+) It causes imbalance of electrolytes such as.

• Arrhythmias (irregular heartbeats): Electrolyte imbalance disrupts the heart's electrical conduction system atrial fibrillation, ventricular tachycardia or ventricular fibrillation It can cause life-threatening arrhythmias such as:

• The danger of fibrillation: Fibrillation (irregular contraction of the heart) interrupts blood flow, which can lead to loss of consciousness and death.

• Monitoring with Holter device: Detection of these rhythm disturbances in animals with heart disease can be done with a Holter monitor.

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3. Vascular Stenosis and Blood Pressure (Hypotension/Hypertension)

During heat stroke, blood vessels dilate (vasodilation) and sudden changes in blood pressure due to fluid loss.

• Hypotension (low blood pressure): Dehydration and dilation of blood vessels reduce the volume of blood in circulation, causing a decrease in blood pressure. This blood pressure (hypotension) It causes the blood flow to the organs to decrease and insufficient blood flow to the organs. Vital organs such as the kidneys, brain and heart are especially affected by this condition.

• Effect of hypotension on the heart: Due to low blood pressure, the heart has to work harder to pump enough blood to the tissues. This poses a life-threatening risk to animals with heart failure.

• Hypertension (high blood pressure): Although rare, in some cases heatstroke overactivates the sympathetic nervous system, causing an increase in heart rate and blood pressure. Hypertension, may increase mitral valve regurgitation (valve leakage) in diseases such as mitral valve disease.

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4. Hypoxia and Cyanosis (Bruising)

During heat stroke hypoxia (lack of oxygen), causes very serious problems in heart patients.

• Breathing quickens: During hyperthermia, the body increases its breathing rate to increase heat loss (hyperventilation). This, overactivity of respiratory muscles and reduces the oxygen exchange efficiency of the lungs.

• Oxygen deficiency (hypoxia)Animals with heart disease already have difficulty meeting oxygen needs due to decreased cardiac output (the amount of blood pumped). This becomes even worse during heat stroke.

• Cyanosis (bruising)If adequate oxygenation is not provided, the gums and mucous membranes purple (cyanosis) color This is an emergency sign that the animal's oxygen levels are dangerously low.

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5. Blood Clotting Disorders (Thromboembolism)

During heat stroke, the body's homeostatic balance (regulatory mechanisms) is disrupted and coagulation disorders (disseminated intravascular coagulation – DIC) can develop.

• Depletion of clotting factors: During heat stroke, blood clotting factors are depleted, which causes disseminated intravascular coagulation. This condition affects the heart in the coronary arteries (vessels that feed the heart) may lead to clot development.

• Arterial thromboembolism: These clots block the vessels that feed the heart muscle. heart attack (myocardial infarction) may increase the risk.

• Paralysis and leg paralysis: Especially in cats with heart disease, a clot can travel from the heart and block the leg arteries in the body. In this case, paralysis of hind legs ve cold, purple paws is observed.

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Precautions to be taken for heart patients

• Do not exercise on hot days: Pets with heart disease should exercise early in the morning or late in the evening, especially in the summer.

• Keep in a cool environmentThe environment where the animal is located must be air-conditioned or cool.

• Prevent excessive weight gain: Excess weight increases the load on the heart.

• Regular cardiological check-upPeriodic check-ups of cats and dogs with heart disease are very important. Cardiology examinations Heart health should be monitored regularly.

Heat stroke (hyperthermia) is a life-threatening condition in cats and dogs with heart disease. In such animals, tachycardia, arrhythmia, heart failure and thromboembolism Complications such as heat stroke can occur. Providing a cool environment, providing access to water, and reducing exercise time are very important to prevent heat stroke. Animals with heart disease have a more fragile heart system and are more vulnerable to environmental stressors such as heat stroke. Early intervention saves lives.

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Clinical Symptoms

Symptoms of heat stroke or hyperthermia can vary depending on the underlying cause. The most common symptoms include:

• difficulty breathing or noisy breathing soul

• Weakness ve loss of coordination (walking like a drunk)

• Collapse (fainting)

• Mumps (sometimes mixed with blood)

• Diarrhea (sometimes mixed with blood)

• Absent-mindedness and drowsiness

• Bruising or bruise-like lesions on the gums and skin

• Nose bleeding

• Seizures or convulsions

If even one of these symptoms is noticed, a veterinarian should be consulted immediately. Heat stroke is a serious condition that threatens the life of the animal.

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Early Intervention

If you notice signs of heatstroke or hyperthermia in your cat/dog, follow these steps:

1. Stop exercising immediatelyIf your pet is running or getting tired, stop it immediately.

2. Move to a cooler area: Move to an air-conditioned area, preferably. If this is not possible, find a shaded area.

3. Start the cooling process:

• To the animal's body cold, wet towels sheep (especially in the neck, chest and abdomen area).

• Do not immerse in ice bath or cold water.Sudden cooling can cause blood vessels to constrict, reducing blood flow to internal organs.

4. Make him drink water: Give your cat/dog water, but do not force it. If there is vomiting or loss of consciousness, water should not be given.

5. Take him to the vet immediately: Go to a veterinary clinic without delay during the cooling process.

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Treatment Applied by the Veterinarian

In the event of hyperthermia/heat stroke, your veterinarian may administer the following treatments:

1. Lowering body temperature:

• Controlled cooling: Cooling measures are taken to slowly reduce the animal's body temperature.

• Physicians do not overcool because of the risk of damage to internal organs if the temperature drops too quickly.

2. fluid therapy:

• Intravenous fluid therapy (IV serum) This supports blood flow to the organs and corrects dehydration.

3. Medication:

• Anti-nausea medicationsIf vomiting is severe, anti-nausea medications are given.

• Antibiotics: Antibiotics may be used if diarrhea or gastrointestinal infection is suspected.

• Sedatives (calming drugs): In animals with upper respiratory tract obstruction, sedation may be required to control respiration.

4. Respiratory support:

• Inserting a tube into the trachea (intubation)In cases where the airways are blocked, a tube is placed in the trachea.

• AnesthesiaIn some animals, anesthesia may be required to keep the trachea open.

5. Treatment of blood clotting disorders:

• Plasma transfusion: In hyperthermia, blood clotting disorder (disseminated intravascular coagulation – DIC) may develop. In this case, plasma transfusion may be required.

6. Heart and blood pressure monitoring:

• ECG (electrocardiography) ve blood pressure monitoring makes. If there is hypotension (low blood pressure) or heart rhythm disturbance, drug treatment is applied.

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Prognosis (Expectation of Recovery)

How well your cat/dog recovers from heatstroke depends on the following factors:

• How long does body temperature remain high?

• What triggers hyperthermia? (for example, being left in a hot car or over-exercising)

• Degree of organ damageComplications such as blood clotting problems, kidney failure, or hypoglycemia (low blood sugar) may reduce the chance of recovery.

• Early interventionEarly cooling and prompt veterinary intervention significantly increase the chance of recovery.

• First 48 hours: The situation in the first 48 hours is very important for the general prognosis. If nervous system symptoms such as seizures or coma occur during this period, the chance of recovery decreases.

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Precautions That Can Be Taken At Home

• Do not leave in vehicle: Do not leave pets in the car in hot weather. The inside of the car heats up much faster than the outside temperature.

• Pay attention to exercise duration: In the summer, exercise in the early morning or in the cool of the evening.

• Provide a cool living space: Let your cat/dog rest in a cool room.

• Ensure access to waterMake sure your pet always has access to clean water.

• Prevent excessive weight gainObesity increases the risk of heat stroke.

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Other Articles You May Be Interested In

• Pulmonary Hypertension
• Ventricular Septal Defect (VSD)
• Congestive Heart Failure in Dogs
• Obesity in Cats and Dogs
• Congestive Heart Failure in Cats

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“Mindfulness is the rarest and purest form of generosity.”

Simone Weil

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