ICU-USA

Glossary H's

Definition:

hardening of the arteries

Definition:common expression for arteriosclerosis

herpes simplex

Definition:infection by the herpes simplex virus, which causes blister-like sores on the face, lips, mouth, or genitals; in rare cases, can also affect the eyes, fingers, or brain

hallucination

Definition:perception that occurs when there is actually nothing there to cause it, such as hearing voices when there are none

hay fever

Definition:common name for allergic rhinitis

hematocrit

Definition:the percentage of total blood volume that consists of red blood cells, which is determined by laboratory testing; can be an indicator of disease or injury

high density lipoprotein (HDL)

Definition:substance that acts as carrier of cholesterol in the bloodstream; commonly referred to as good cholesterol; low levels are a risk factor for coronary artery disease; count ranges-less than 35 is high risk factor, 35-59 is borderline, over 60 is desirable

heat exhaustion

Definition:fatigue, dizziness, and nausea experienced due to overexposure to heat; if not treated it can result in heat stroke

heat stroke

Definition:life-threatening condition resulting from extreme overexposure to heat, which disrupts the body's system of regulating temperature

Heimlich maneuver

Definition:first-aid technique for choking; dislodges an object blocking a person's airway

hemangioma

Definition:purple-red mark on the skin, caused by an excess of blood vessels

hemarthrosis

Definition:bleeding into and swelling of a joint

hematemesis

Definition:vomiting of blood

hematoma

Definition:accumulation of blood from a broken blood vessel

hematuria

Definition:blood in the urine, which can be caused by urinary tract disorders (e.g., cysts, tumor, or stones) or by an infection

hemodialysis

Definition:type of dialysis used to treat kidney failure, in which blood is passed through a machine that purifies it and returns it to the body; a variety of hemodialysis techniques exist

hemoglobinuria

Definition:hemoglobin in the urine

hemophilia

Definition:inherited disorder in which a person's blood lacks a certain protein important in forming blood clots, leading to excessive bleeding

hemorrhagic

Definition:pertaining to bleeding or hemorrhage

hemorrhoid

Definition:bulging vein either at the opening of the anus or just inside the anus, often caused by childbirth or straining during bowel movements

hemostasis

Definition:stopping of bleeding by the body's mechanisms

hemolysis

Definition:breakdown of red blood cells in the spleen, which is normal but can cause jaundice and anemia when the red blood cells are broken down too quickly

hepatitis A

Definition:form of hepatitis caused by the hepatitis A virus, usually transmitted by contact with contaminated food or water

hepatectomy

Definition:surgical removal of all or part of the liver

hepatic

Definition:pertaining to the liver

hepatitis

Definition:inflammation of the liver, which may be caused by a viral infection, poisons, or the use of alcohol or other drugs

hepatoma

Definition:cancerous tumor of the liver

hepatomegaly

Definition:enlargement of the liver

hepatitis B

Definition:form of hepatitis, generally more serious than hepatitis A, caused by the hepatitis B virus, which is transmitted through sexual contact or contact with infected blood or body fluids

hepatitis C

Definition:form of hepatitis caused by the hepatitis C virus, which is transmitted through sexual contact or contact with infected blood or body fluids

hepatitis D

Definition:form of hepatitis that only causes symptoms when the individual is already infected with hepatitis B

hereditary

Definition:describes a genetic trait that is passed from parents to children

hernia

Definition:bulging of an organ or tissue through a weakened area in the muscle wall

herpes encephalitis

Definition:brain inflammation caused by a herpes simplex virus that has spread from another part of the body

heterosexuality

Definition:being sexually attracted to members of the opposite sex

hemoglobin

Definition:pigment in red blood cells that is responsible for carrying oxygen; hemoglobin bound to oxygen gives blood its red color

hemolysis

Definition:breakdown of red blood cells in the spleen, which is normal but can cause jaundice and anemia when the red blood cells are broken down too quickly

home health aide

Definition:persons who assist ill, elderly or disabled people in the home, providing personal care and housekeeping tasks

hiatal hernia

Definition:type of hernia in which the stomach bulges up into the chest cavity through an opening in the diaphragm

hiccup

Definition:involuntary, sudden contraction of the diaphragm along with the closing of the vocal cords, producing a hiccup sound

Hickman catheter

Definition:see central venous catheter; also called Hickman line

human immunodeficiency virus (HIV)

Definition:retrovirus that attacks helper T cells of the immune system and causes acquired immunodeficiency syndrome (AIDS); transmitted through sexual intercourse or contact with infected blood

hives

Definition:common term for urticaria, an itchy, inflamed rash that results from an allergic reaction

homeostasis

Definition:the body's coordinated maintenance of the stable, internal environment by regulating blood pressure, blood sugar, body temperature, etc

homosexuality

Definition:being sexually attracted to members of the same sex

hormone

Definition:chemical produced by a gland or tissue that is released into the bloodstream; controls body functions such as growth and sexual development

hospice care

Definition:specialized, supportive health care provided to the dying person; in addition to meeting the person's immediate physical needs, often emotional, financial, legal, and spiritual counseling are provided to the individual and family; may be provided at home, hospital, long-term care facility or specialized facility called a hospice; may be used to describe any facility providing such care

hot flash

Definition:sudden, temporary feeling of heat and sometimes sweating; usually occurs as a result of low estrogen levels in women because of menopause or after a hysterectomy

heart arrest

Definition:sudden cessation of the heart's effectiveness in pumping blood

heart block

Definition:disorder of the heart caused by a blockage of the electrical impulses that regulate heartbeat; may lead to dizziness, fainting, or stroke

heart failure

Definition:inability of the heart to pump blood effectively

heart rate

Definition:rate at which the heart pumps blood, measured in the number of heartbeats per minute

heart valve

Definition:structure at each exit of the four chambers of the heart that allows blood to flow out but blocks it from flowing back in

heart-lung machine

Definition:machine that takes over the functions of the heart and lungs during certain types of surgery

hormone replacement therapy

Definition:use of natural or artificial hormones to treat hormone deficiencies

heartburn

Definition:burning sensation experienced in the center of the chest up to the throat; may be caused by overeating, eating spicy food, or drinking alcohol; recurrent heartburn may be caused by acid reflux from the stomach into the esophagus

human T-cell lymphotrophic virus (HTLV)

Definition:virus similar to HIV that affects the same helper T cells, but usually accompanies adult T

hypertension

Definition:abnormally high blood pressure, even when at rest

hemothorax

Definition:accumulation of blood between the chest wall and the lungs

hydrocephalus

Definition:excess cerebrospinal fluid within the brain; commonly referred to as water on the brain

hydrocortisone

Definition:corticosteroid drug used to treat inflammation and allergies

hygiene

Definition:the practice, maintenance, and study of health; commonly refers to cleanliness

hygienic

Definition:pertaining to hygiene

hyperalimentation

Definition:method of providing nutrients by the use of a tube or intravenously to a person who cannot eat food or needs nutrients because of an illness

hyperbilirubinemia

Definition:condition in which there is too much bilirubin, a substance produced when red blood cells are broken down; can lead to jaundice

hypercalcemia

Definition:condition marked by abnormally high levels of calcium in the blood; can lead to disturbance of cell function in the nerves and muscles and, if not treated, can be fatal

hypercholesterolemia

Definition:abnormally high level of cholesterol in the blood, which can be the result of an inherited disorder or a diet that is high in fat

hyperglycemia

Definition:condition characterized by abnormally high levels of glucose in the blood, usually as a result of untreated or improperly controlled diabetes mellitus

hyperlipidemia

Definition:general term for a group of disorders in which lipid levels in the blood are abnormally high, including hypercholesterolemia

hyperparathyroidism

Definition:over activity of the parathyroid glands, which increases calcium levels in the blood (called hypercalcemia) and decreases calcium in bones, causing osteoporosis

hyperplasia

Definition:abnormal enlargement of an organ or tissue

hypersensitivity

Definition:excessive response of the body's immune system to foreign substances

hyperthermia

Definition:abnormally high body temperature

hyperthyroidism

Definition:over activity of the thyroid gland, causing nervousness, weight loss, fatigue, and diarrhea

hypertrophy

Definition:increase in the size of an organ due to an increase in the size of its cells

hyperventilation

Definition:abnormally rapid breathing

hypochondriasis

Definition:abnormal condition in which a person is overly concerned with health and believes that he or she is suffering from a major illness despite medical opinion to the contrary

hypodermic needle

Definition:thin, hollow needle attached to a syringe; used to inject a medication under the skin, into a vein, or into a muscle

hypoglycemia

Definition:abnormally low levels of glucose in the blood

hypoplasia

Definition:failure of a tissue or organ to develop normally

hypotension

Definition:abnormally low blood pressure, which results in reduced blood flow to the brain, causing dizziness and fainting

hypothalamus

Definition:part of the brain that lies below the thalamus and secretes substances that control metabolism by influencing pituitary gland function; also involved in regulation of body temperature, water balance, blood sugar and fat metabolism and regulates glands such as ovaries, parathyroids, and thyroid

hypothermia

Definition:abnormally low body temperature

hypothyroidism

Definition:under activity of the thyroid gland, causing fatigue, cramps, a slowed heart rate, and possibly weight gain

hypoventilation

Definition:abnormally slow breathing rate

hypoxemia

Definition:reduced level of oxygen in the blood

hypoxia

Definition:reduced level of oxygen in tissues

hysterectomy

Definition:surgical removal of the uterus

hysteroscopy

Definition:method used to examine the inside of the uterus and the cervix using a viewing instrument