Blood Test: Treatment, Effect & Risks

In a blood test, blood sample or blood test, information is obtained from drawn blood through various laboratory tests. Since blood is the essence of our lives, it contains a variety of information that allows conclusions to be drawn about the state of our health.

What is a blood test?

In a blood test, blood sample or blood test, information is obtained from drawn blood through various laboratory tests. The blood tests can be performed not only on whole blood, but also on serum or blood plasma. Despite the many different examination options, one blood sample is usually sufficient, since most tests can be performed with only 2 ml of blood. On the basis of a blood test, it is also possible to draw conclusions about the condition of individual organs. This is achieved by means of certain proteins, the so-called enzymes, which are found in the blood and whose presence provides information about the state of health of the respective organ. However, many other tests can be performed as part of a blood test. Therefore, a basic distinction is first made between a small and a large blood count.

Function, effect and goals

Within the scope of the small blood count, the values of the blood platelets, also called thrombocytes, the white blood cells, called leukocytes, and the red blood cells, the erythrocytes, are examined. Furthermore, the concentration of hemoglobin is examined. This type of blood test allows conclusions to be drawn about the patient’s general state of health. These values can also be used to determine whether the patient has a weakened immune system, inflammatory foci in the body, deficiency symptoms or problems with blood clotting. If a large blood count is performed as part of a blood test, this serves to break down the information from the small blood count more precisely. By counting or taking a blood smear, the shape of the red blood cells and the percentages of the different types of blood cells can be determined. In the area of organs, a blood test can provide information about the health of the heart, gall bladder, liver, digestive organs, pancreas and muscles based on certain enzymes. A blood culture can be taken to detect certain pathogens, such as bacteria or viruses. This attempts to multiply the pathogens and thereby identify them. This allows the doctor to find out the right therapy. This type of blood test can be useful in cases of sepsis, endocarditis, unexplained fever or pneumonia. If the coagulation property of the blood is to be examined by the blood test, a blood coagulation test is performed. Here, different test procedures are used to examine the consistency of the blood test. Blood coagulation tests are used in cases of upcoming surgery, susceptibility to thrombosis, and to monitor the use of blood thinning agents. If the blood test is done to determine if there is a focus of inflammation in the body, a blood cell sedimentation rate test can be done. The rate at which blood cells sink is accelerated or slowed by various infectious diseases, so this blood test can provide an indication of the type of infection. In a blood test of the blood serum, various antibodies can be detected. These in turn indicate an existing infection. However, since some antibodies remain in the blood permanently, this type of blood test is only of limited significance. Since the levels of certain hormones in the blood can indicate disturbed functions of certain glands, a blood test can also be performed with regard to the hormones contained in the blood. However, this examination can be used not only to control the hormonal glands, but it also allows to detect pregnancy and its controlled course. However, it is also important to have constant values of certain electrically charged particles, electrolytes, such as potassium, calcium, magnesium, phosphate or sodium. These are needed to maintain important bodily functions. Since insufficient levels of the various electrolytes can lead to serious problems such as cardiac arrhythmias, muscle weakness or paralysis, such a blood test is helpful in investigating the causes of the above-mentioned and many other diseases.

Risks and dangers

When blood is drawn for a blood test, there are generally no side effects or dangers to be expected. The puncture site is kept as small as possible by the physician and further bleeding is stopped by immediate subsequent pressure on the puncture site. However, it is important that no hasty conclusions are drawn during the blood tests, because many results can indicate different diseases. For this reason, results should always be cross-checked with different tests and a thorough medical history.