Dictionary

hyperadrenocorticism See Cushing’s syndrome.

hyperaldosteronism See aldosteronism.

hyperbaric oxygen chamber A pressurized chamber in which a patient receives pure oxygen, either directly or through a mask, tent, or tube. The oxygen is delivered at high pressure, more than 1.4 times normal atmospheric pressure. See also hyperbaric oxygen therapy.

hyperbaric oxygen therapy The use of a hyperbaric oxygen (HBO) chamber to treat any of a number of conditions, notably carbon monoxide poisoning, decompression sickness (“the bends”), smoke inhalation, and gas gangrene. HBO therapy also helps to heal skin grafts, major burn injuries, and it is sometimes used in cases of antibioticresistant or severe infection….

hyperbilirubinemia An elevated level of the pigment bilirubin in the blood. A sufficient elevation of bilirubin produces jaundice. Some degree of hyperbilirubinemia is very common right after birth, especially in premature babies. Treatment of hyperbilirubinemia in the newborn involves exposure of the skin to special lights and removal of serum from the blood and replacing…

hyperbilirubinemia type 1 See Gilbert syndrome.

hypercalcemia A higher-than-normal level of calcium in the blood. Hypercalcemia can be a result of malignancy, elevated parathyroid gland activity (hyperparathyroidism), or other conditions. It can cause a number of nonspecific symptoms, including loss of appetite, nausea, thirst, fatigue, muscle weakness, restlessness, and confusion. An elevated level of calcium may cause muscle weakness and constipation,…

hypercalciuria Excessive excretion of calcium in the urine, which may cause calcium kidney stones. Overactivity of the parathyroid gland (hyperparathyroidism) may cause excess calcium in the bloodstream (hypercalcemia) with increased excretion of calcium in the urine. See also hypercalcemia.

hypercapnia A greater than normal level of carbon dioxide in the blood.

hypercholesterolemia High blood cholesterol. See also familial hypercholesterolemia.

hypercoagulable state A condition in which there is an abnormally increased tendency toward blood clotting (coagulation). There are numerous hypercoagulable states. Each has different causes, and each increases a person’s chances of developing blood clots, such as those associated with thrombophlebitis (inflammation due to a clot in the veins). The causes include medications (particularly female…

hyperemesis gravidarum Extreme, excessive, and persistent vomiting in early pregnancy that may lead to dehydration and malnutrition. It is usually associated with weight loss of more than 5 percent of the woman’s prepregnancy weight. Hyperemesis gravidarum affects about 1 in every 300 pregnant women and is most common in young women, in first pregnancies, and…