Health A-Z

Heart Ventricles

Clinical Definition The ventricles are the two lower chambers of the heart. In Our Own Words The heart is divided in two halves by a wall or septum. Each half of the heart has a smaller upper chamber (atrium) and a larger lower chamber (ventricle). The ventricles receive blood from the atria. The right half

Heat Exhaustion

Clinical Definition Heat exhaustion is a reaction to prolonged exposure to high temperatures. It develops due to a depletion of electrolytes and dehydration without adequate replenishment. It is characterized by weakness, prostration and tachycardia. If heat exposure is allowed to continue, the condition may progress into heat stroke. In Our Own Words Normally, your body

Heat Stroke

Clinical Definition Heat stroke is the most severe of three types of heat emergencies, also including heat cramps and heat exhaustion. Heat stroke can cause shock, brain damage, organ failure and death. Fever, irrational behavior and confusion are common. In Our Own Words Heat stroke is the most severe form of heat-related illness and can


Clinical Definition Hematuria, or blood in the urine, indicates that red blood cells are present. Even if you cannot see blood, you might have microscopic blood in your urine. Normally, the kidneys prevent blood from entering urine, but blood coming from the kidneys or other parts of the urinary tract (ureters, bladder, prostate, urethra) can


Clinical Definition Hemorrhoids are dilated vascular structures under the rectal mucosa. Hemorrhoids may develop outside of the external anal sphincter or inside the anal canal. They are often due to increased pressure on the anorectal area. Increased pressure may be due to constipation and straining during bowel movements. In Our Own Words Very common among


Clinical Definition A hernia is a bulge or protrusion of one organ or tissue through a wall or partition that normally contains it or holds it in. Hernias can develop in any number of locations in the human body, but often involve a portion of the gastrointestinal tract bulging through the abdominal/pelvic wall. In Our

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