Blood for analysis. We rent out correctly!
We donate blood for analysis correctly. 9022.jpeg
Just think, what is the importance – to donate blood correctly! But still, there are some subtleties in this matter. Before donating blood for analysis, it is necessary to learn a number of rules, without which an accurate result is impossible. So how do you do it right? Readers of MedPulse are advised by laboratory diagnostics doctor Alla Snegireva.
Why from a vein?
To take blood from a finger, of course, is not so scary and not so painful. But most often venous blood is taken for laboratory research. The exception is a narrow range of clinical tests, for example, a general blood test. If you need to conduct a biochemical study or determine the level of hormones, then you will need at least 2 ml of blood, and such an amount can be collected only from a vein. Finger blood sampling is sometimes allowed for general analysis in children. Before or after a meal? Some studies require prior preparation – in particular, restrictions on food intake.
On an empty stomach, biochemical studies are performed: glucose, creatinine, bilirubin, triglycerides, lipid profile; blood test for infections: syphilis, hepatitis B antigen; and various hormones. Carefully adhere to the doctor’s recommendations: if you need to donate blood on an empty stomach, then at least 8 hours should pass between the last meal and blood collection, and at least 12 hours for triglycerides. Juice, tea, coffee, especially sugar, are also food, so you have to be patient. You can drink only water. One to two days before the examination, it is desirable to exclude fatty, fried and alcohol from the diet. If on the eve an abundant feast took place – postpone the laboratory test for a day or two, and refrain from smoking one hour before taking the blood. If you have to take a general blood test, the last meal should be no earlier than an hour before the procedure and may consist of unsweetened tea, porridge – without sugar, milk and butter. You can donate blood for antibodies to HIV infection, viral hepatitis, rubella, cytomegalovirus and a number of other infections in the morning, afternoon or evening, and without preliminary fasting.
And one moment. The content of many blood parameters is subject to daily – the so-called circadian – fluctuations. Therefore, blood for determination of thyroid-stimulating hormone, parathyroid hormone, as well as iron is given on an empty stomach, strictly before 10 a.m. In general, it is advisable to always conduct a study of the concentration of hormones at the same time – in this case, a comparative analysis of the results will be more correct.
Do not overexert
It has been established that physical and emotional stress can have a rather tangible effect on some blood parameters. It can be brisk walking, running, intense climbing stairs. The result of the analysis can even be affected by a feeling of fear of the procedure for taking blood. To reduce the negative impact of these factors, it is recommended to rest in the waiting room and calm down before the procedure.
Tablets are contraindicated
Taking medications, such as antibiotics or chemotherapeutic drugs, can also affect the result of the analysis. Therefore, blood must be donated before the start of their intake or not earlier than 10-14 days after their cancellation. The only exceptions are cases when they want to measure the concentration of drugs in the blood. If you are taking any medications, be sure to notify your doctor and procedural nurse about this.
Blood should not be donated immediately after radiography, rectal examination, or physiotherapeutic procedures. If the result is negative. When examining blood for infections, it should be taken into account that, depending on the period of infection and the state of the immune system, a negative result can be obtained in any person. However, he does not completely rule out infection. In doubtful cases, it is recommended to conduct a second study – after a while. But not earlier than in 3-4 weeks.
We are talking about hormonal studies in women of the so-called reproductive age – from 12-13 years old and before menopause. During this period, the results of the analysis are affected by physiological factors associated with the stage of the menstrual cycle. When conducting research on sex hormones, strictly adhere to the recommendations of your doctor. If there are no other recommendations, then, as a rule, blood for determining the level of FSH and LH is given on the 4th-6th day of the menstrual cycle. And blood for determining the level of estradiol and progesterone – on the 21-23th day of the cycle. Is anonymity possible? Yes, many laboratories can conduct an anonymous screening. But if you need an official documented result, bring your passport with you. Please note that anonymous analyzes are not accepted in the following cases: during hospitalization, in OVIRs and embassies.