 | Blood test: Encyclopedia - Blood test
Blood test
Blood tests are laboratory tests done on blood to gain an appreciation of disease states and the function of organs. Since blood flows throughout the body, acting as a medium for providing oxygen and other nutrients, and drawing waste products back to the excretory systems for disposal, the state of the bloodstream affects, or is affected by, many medical conditions. For these reasons, blood tests are the most commonly performed medical tests. Blood is obtained from a patient by venipuncture, except for tests such as Arterial blood gas.
Blood is useful as it is a relatively non-invasive way to obtain cells, and extracellular fluid (plasma), from the body to check on its health. Although the term blood test is used, most routine tests (except for most haematology) are done on plasma or serum.
The list below includes both specific tests, and general techniques.
Blood test - Blood chemistry tests
The CHEM-7 test is a battery of blood chemistry tests. The seven parts of a CHEM-7 include tests for:
- Four electrolytes:
- sodium [1]
- potassium [2]
- chloride [3]
- bicarbonate or CO2 [4]
- blood urea nitrogen (BUN) [5]
- creatinine [6]
- glucose [7]. (This test can also be performed directly by diabetic patients by using a glucose meter.)
One common use for these tests is to determine renal function.
While the regular glucose test is taken at a certain point in time, the glucose tolerance test involves repeated testing to determine the rate at which glucose is processed by the body.
While the above tests are all taken from veinous blood, by constrast the arterial blood gas test is, as its name would suggest, taken from arterial blood, and is therefore more dangerous and uncomforable.
Reference ranges for common blood tests (with a much longer list), Urine test, Blood diseases, HIV test (uses several different techniques, including ELISA test and Western blot), Blood film, Hematology, Microbiology
Blood test - Large organic molecules
Blood test - proteins
- Protein electrophoresis (general technique -- not a specific test)
- Western blot (general technique -- not a specific test)
- Liver function tests
- Serology (general technique -- not a specific test)
- Wassermann test (for syphilis)
- ELISA test
- Cold agglutinins test [8]
Blood test - Other
- Polymerase chain reaction (DNA). DNA testing is today possible with even very small quantities of blood: this is commonly used in forensic science, but is now also part of the diagnostic process of many disorders.
- Northern blot (RNA)
Blood test - Cells
- Full blood count (or "complete blood count")
- Hematocrit and MCV ("mean corpuscular volume")
- Erythrocyte sedimentation rate (ESR)
- Cross-matching. Determination of blood type for blood transfusion or transplants
- Blood cultures are commonly taken if infection is suspected. Positive cultures and resulting sensitivity results are often useful in guiding medical treatment.
See also
- Reference ranges for common blood tests (with a much longer list)
- Urine test
- Blood diseases
- HIV test (uses several different techniques, including ELISA test and Western blot)
- Blood film
- Hematology
- Microbiology
Categories: Medical tests | Hematology
Other related archivesArterial blood gas, Blood cultures, Blood diseases, Blood film, Cross-matching, DNA testing, ELISA test, Erythrocyte sedimentation rate, Full blood count, HIV test, Hematocrit, Hematology, Liver function tests, MCV, Medical tests, Microbiology, Northern blot, Polymerase chain reaction, Protein electrophoresis, Reference ranges for common blood tests, Serology, Urine test, Wassermann test, Western blot, arterial blood gas, bicarbonate, blood, blood transfusion, blood type, blood urea nitrogen, cells, chloride, creatinine, diabetic, disease, electrolytes, extracellular fluid, forensic science, glucose, glucose meter, glucose test, glucose tolerance test, haematology, laboratory, medical tests, non-invasive, oxygen, plasma, potassium, renal function, serum, sodium, transplants, venipuncture
 Adapted from the Wikipedia article "Blood test", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki |
