Heatstroke is a potentially life-threatening condition caused by the body's inability to cool itself. Usually, as body temperature rises, the skin sweats to cool down the body. In some conditions, such as severe humidity or extreme physical activity, sweating is not enough to keep the body cool. In this case, the body temperature continues to rise, resulting in heat exhaustion that can lead to heatstroke. Doctors at the Mayo Clinic define heatstroke as a body temperature of 104 degrees or higher. Heatstroke affects the body in many ways.
Dehydration
Dehydration is the loss of water and essential body salts such as sodium, potassium, calcium bicarbonate and phosphate. Dehydration is a common effect of heat stroke as overexposure to the sun causes the cells of the body to lose water. The symptoms of dehydration include excessive thirst, infrequent urination, dry skin, fatigue, lightheadedness, dizziness and confusion.
Dry, Hot Skin
A person suffering from heatstroke has dry skin that is hot to the touch. The skin appears flushed because, as the temperature of the blood rises, the body tries to dissipate the heat through the capillaries. Capillaries are the tiny blood vessels that are responsible for exchanging oxygen and carbon dioxide into and out of the cells. As the capillaries release excess heat to the tissues, the skin appears red.
Increased Heart Rate
In an attempt to cool the body by pumping more blood into the capillaries to dissipate the heat, the heart works harder and pumps faster during heatstroke. This causes a rapid pulse rate, a condition known as tachycardia.
Muscle Cramps
As the body becomes dehydrated, cells in the muscles lose water and minerals, resulting in muscle cramps. Muscle cramps often occur during heat exhaustion, so they can serve as a warning sign that heatstroke may occur.
Neurological Changes
The changes in the body due to the high temperature of heatstroke can have many neurological effects. As the body tries to protect the vital organs, it may shut down some other parts of the body. This can lead to periods of confusion, speech impairments, loss of consciousness, hallucinations, seizures or even coma.
Shock
If the above symptoms are not recognized as effects of heatstroke and medical treatment is not received, the ultimate effect is shock. Shock is a condition characterized by a sudden loss of blood flow. A decrease in blood pressure, blue lips and cold, clammy skin are all signs of shock. Reaching a state of shock can cause organs in the body to swell, and result in permanent damage.
