Preparing for a biochemical blood test: rules and advice

Conscientious preparation for blood donation for biochemical analysis is the opportunity to get the most reliable result. Contraindications to this type of research is not revealed.

How to take an analysis, the algorithm of actions

A biochemical blood test is taken by a medical worker at a health facility. For the analysis, venous blood from the ulnar vein is required. The patient sits on a chair or a couch, the arm above the elbow is pinched by a special rubber or plastic tow. The puncture site is disinfected and the needle is inserted into the vein. Collect the necessary amount of blood in a test tube. The puncture site is again disinfected. The patient is recommended to hold his hand for a few minutes in a bent state at the elbow. Manipulation lasts about two minutes. From laboratory tests will depend on the time of the research. The results of the usual biochemical analysis are ready for the next day.

Some features of the preparatory phase

The rules of preparation for the biochemical analysis of blood depend on which parameters the doctor wrote out the directions:

1. Lipid spectrum and cholesterol level. Blood sampling is carried out only after 14 hours of hunger. For 15 days, in consultation with the treating doctor, exclude the use of drugs that affect lipid metabolism. If it is necessary to evaluate the effectiveness of drug therapy, the drugs do not cancel.
2. Urea. For two days it is desirable to adhere to a certain diet: exclude offal (kidney, liver), minimize the intake of meat, fish products, tea and coffee. Physical activity should be moderate.
3. Uric acid. A couple of days before the study, follow the recommendations mentioned in the previous paragraph. In addition, the following medicines must be excluded: antibacterial and sulfanilamide preparations, salicylates, caffeine, vitamin C, thiazole derivatives, theobromine and theophylline.
4. Alfa-2-macroglobulin. Before the analysis of blood on this indicator for three days should abandon the meat products.
5. A hormone that influences growth factors or antimulylerov hormone, glycoprotein or inhibin B. Analysis for these hormones is carried out in the interval between the third and fifth day of menstruation. Three days before the test, physical exercises are not recommended. An hour before the study, to exclude smoking. During diseases, especially in the acute phase, it is better not to pass the analysis.
6. When preparing for the biochemical analysis of blood for hormones ACTH, cortisol, it is proposed to exclude alcohol-containing drinks, exercise, smoking, stressful situations, taking contraceptive drugs, estrogens and glucocorticoids. The best time to obtain reliable and informative results is no later than two hours after a night's sleep and no later than 10 am.
7. Bilirubin. On the eve of the study, do not consume vitamin C and products that can stain blood serum.
8. Sex hormones. The exact time of taking blood for this type of hormones is indicated by the gynecologist, depending on the physiological state of the woman (menopause, pregnancy, menstruation).
9. An analysis of infectious diseases can also be false positive. To exclude doubt, the study is re-administered. With the diagnostic purpose, the analysis is performed before the treatment with antibiotics. To assess the effectiveness of therapy, blood is taken no earlier than 14 days after completion of the course of treatment.

Analysis for allergy

To diagnose allergic reactions requires special preparation for blood sampling for biochemical analysis:

• For 2 days completely exclude alcohol, medicines (in agreement with the doctor), biologically active substances, including vitamins;
• The study is not conducted in cases of cytostatics, hormones and radiation therapy, since in this case, the synthesis of immunoglobulin is inhibited;
• For reliability and exclusion of false positive results, it is necessary to not take antiallergenic drugs 7 days before the test;
• The study is performed on an empty stomach.

From contraindications it should be noted: acute period of the disease, menstruation, antibacterial therapy.

Food intake

Preparation of the patient for biochemical analysis of blood includes the exclusion of food before manipulation. Nutrients, absorbed in the intestines after eating:

• Change the concentration of carbohydrates, fats, proteins, hormones and other substances;
• Activate the work of enzymes;
• Increase or decrease the viscosity of the blood.

As a result, the results of the blood test will be unreliable.

Ideal is the delivery of the analysis in the morning after a night's sleep - on an empty stomach. If there are certain difficulties in meeting this rule, then the following points must be adhered to:

• For two days not to eat fried foods;
• For 24 hours to exclude the use of caffeine-containing beverages;
• On the day preceding the surrender of the analysis, dinner should be easy;
• At least 4 hours before the test is done, do not eat fatty foods, because the high concentration of fatty substances in the blood distorts the result;
• Do not use fizzy, dairy (lactic acid) and coloring drinks, juices. Water has little effect on the final result, but it is better to refrain from taking it;
• Do not take a biochemical blood test after a heavy meal (feast).

Preparation for biochemical analysis of blood: taking medications

The effect of many drugs on the results of laboratory tests, including the biochemical analysis of blood, has been studied in detail. However, it is impossible to predict in advance how the result of research will change, taking into account the individual characteristics of the organism of a particular individual and the presence of chronic diseases. In order for the doctor to correctly interpret the results obtained in the laboratory, the medical worker should be warned about the medicines being taken. It is advisable to discuss with the doctor in advance the possibility to stop taking certain medications for a while.

Emotional state and physical activity

Preparation for biochemical analysis of the blood of an adult depends on his emotional state, since any stressful situation affects the human body. Under stress, the sympathoadrenal component of the system of neurohumoral regulation is activated, which in turn leads to increased production of hormones and enzymes that lead to a change in the activity of the internal organs of the individual. The whole complex of these processes affects the results of the analyzes. Physical loads also activate the internal systems of the body, especially hormonal and enzyme, and as a result, the number of biologically active substances increases in the circulatory system, metabolism is more intensive, internal organs work more actively. In order to exclude the influence of the above factors in the preparation for the biochemical analysis of blood, it is desirable to:

• Exclude any physical activity and exercise;
• Keep the emotional background in a state of equilibrium: not to allow a violent explosion of emotions;
• Immediately before performing the manipulation it is recommended to sit quietly and relax.

Bad habits

Alcoholic drinks affect all processes occurring in the body of the individual. The decomposition products of alcohol-containing beverages adversely affect the work of the enzyme systems of the body, affect water-salt metabolism and cellular respiration. Smoking affects the tone of the vascular system, increases the work of the nervous system, increases the concentration of hormonal substances. All these processes lead to significant changes in the biochemical parameters of the blood. In order to reduce the harmful effects in preparing for a biochemical blood test, it is recommended:

• 30-60 minutes before taking the test do not smoke;
• For 72 hours - to exclude the use of alcohol-containing drinks.

Female physiology

The physiological state of a woman is subject to change within a month. Biochemical blood test for such an indicator as hormones (follicle-stimulating, luteinizing, estradiol, prolactin, progesterone, androstenedione and others) is recommended to take a certain day of menstruation or pregnancy. This is due to a significant change in the concentration of both sex hormones and their metabolites. Pregnancy also influences the final results of studies, since during this period hormonal changes in the body occur, and depending on the period of pregnancy, the concentration of a number of substances in the body changes: proteins, enzymes, hormones and others. How can I submit a biochemical blood test? Preparation for it is determined by a gynecologist individually for each woman.

Times of Day

There are some types of biochemical indicators, the magnitude of which depends on the time of day, for example, specific markers of metabolism in bone tissue. If the doctor assigns this analysis for monitoring purposes, then it should be taken at the same time.

With proper preparation for the analysis of blood for biochemical research, the result will be as accurate as possible and allow the doctor to diagnose and prescribe the appropriate treatment.