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Glossary

Showing 541-550 out of 1184 Terms

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  • Healthcare proxy

    (HELTH-kayr PRAK-see)

    A type of advance directive that gives a person (such as a relative, lawyer, or friend) the authority to make healthcare decisions for another person. It becomes active when that person loses the ability to make decisions for himself or herself. Also called HCP.

  • Heart attack

    A heart attack happens when the flow of oxygen-rich blood in one or more of the coronary arteries, which supply the heart muscle, suddenly becomes blocked, and a section of heart muscle can’t get enough oxygen. The blockage is usually caused when a plaque ruptures. If blood flow isn’t restored quickly, either by a medicine that dissolves the blockage or a catheter placed within the artery that physically opens the blockage, the section of heart muscle begins to die.

  • Hematocrit

    (hee-MA-toh-krit)

    The amount of whole blood that is made up of red blood cells. It depends on the number and size of red blood cells. A hematocrit test is usually part of a complete blood count (CBC). It may be used to check for conditions such as anemia, dehydration, malnutrition, and leukemia. Also called HCT.

  • Hematologist

    HEE-muh-TAH-loh-jist

    A doctor who has special training in diagnosing and treating blood disorders.

  • Hematology

    A medical science that deals with the blood and blood-forming organs.

  • Hematology/oncology

    The branch of medical science that treats disorders of the blood, blood forming tissues and tumor cells.

  • Hematoma

    (HEE-muh-TOH-muh)

    A pool of mostly clotted blood that forms in an organ, tissue, or body space. A hematoma is usually caused by a broken blood vessel that was damaged by surgery or an injury. It can occur anywhere in the body, including the brain. Most hematomas are small and go away on their own, but some may need to be removed by surgery.

  • Hematuria

    (HEE-muh-TOOR-ee-uh)

    Blood in the urine; urine may be pink, red, or brown (coke colored).

  • Hemoglobin

    HEE-moh-GLOH-bin

    A protein inside red blood cells that carries oxygen from the lungs to tissues and organs in the body and carries carbon dioxide back to the lungs. Testing for the amount of hemoglobin in the blood is usually part of a complete blood cell (CBC) test.

  • Hemolysis

    (hee-MAH-lih-sis)

    The breakdown of red blood cells. Some diseases, medicines, and toxins may cause red blood cells to break down more quickly than usual.