Dictionary

Labs and diagnostics

Lab values with their normal and critical ranges, and the tests nurses prepare clients for.

hematocritA blood test that shows what share of the blood's volume is made up of red blood cells, given as a percentage.

hemoglobinThe iron-containing protein in red blood cells that carries oxygen, and the blood test that measures it.

hemoglobin A1CA blood test that shows a person's average blood sugar over the past 2 to 3 months.

hemolysisThe breaking apart of red blood cells, which releases hemoglobin into the blood.

hepatitis B surface antigenA blood test for a protein from the outer coat of the hepatitis B virus.

high-density lipoproteinA particle in the blood that carries cholesterol away from the arteries to the liver; its level is part of a lipid panel.

histologyThe study of body tissues under a microscope.

HIV testA blood or saliva test that looks for signs of the human immunodeficiency virus (HIV).

Holter monitorA small portable device that records the heart's electrical activity continuously, usually for 24 to 48 hours.

human chorionic gonadotropinA hormone made by the placenta during pregnancy, measured in blood or urine as a pregnancy test.

hyperbilirubinemiaToo much bilirubin, a yellow waste product of old red blood cells, in the blood.

hypercalcemiaA blood calcium level above normal.

hypercapniaToo much carbon dioxide in the blood, a PaCO2 above 45 mm Hg.

hyperchloremiaA blood chloride level above normal, over 106 mEq/L.

hyperglycemiaA blood glucose level above normal, over 100 mg/dL when fasting.

hyperkalemiaA blood potassium level above normal, over 5.0 mEq/L.

hyperlipidemiaHigher than healthy levels of fats (lipids), such as cholesterol or triglycerides, in the blood.

hypermagnesemiaA blood magnesium level above normal.

hypernatremiaA blood sodium level above normal, over 145 mEq/L.

hyperosmolarHaving more dissolved particles per unit of fluid than normal, so the fluid pulls water toward itself.

hyperphosphatemiaA blood phosphate (phosphorus) level above normal.

hypocalcemiaA blood calcium level below normal.

hypochloremiaA blood chloride level below normal, under 98 mEq/L.

hypoglycemiaA blood glucose level below normal, under 70 mg/dL.

hypokalemiaA blood potassium level below normal, under 3.5 mEq/L.

hypomagnesemiaA blood magnesium level below normal.

hyponatremiaA blood sodium level below normal, under 135 mEq/L.

hypophosphatemiaA blood phosphate (phosphorus) level below normal.

hypoxemiaA level of oxygen in the blood below normal.