What is a full blood count?
It is a basic examination that is usually prescribed by both the family doctor and specialists.
“If a patient complains of feeling unwell, the doctor will most likely send for this analysis, because its results allow you to get a general picture of the state of health and decide in which direction to continue the investigation to determine the diagnosis,” explains the doctor and adds that the complete blood count analysis includes several indicators – hemoglobin, erythrocytes, reticulocytes, platelets, leukocytes (neutrophils, eosinophils, basophils), lymphocytes and monocytes. “Each has its own functions. For example, leukocytes are responsible for immune protection, platelets for blood clotting, while erythrocytes ensure the transport of oxygen and carbon dioxide,” says Jana Osīte, head of “Central Laboratory”, laboratory doctor.
Blood can be taken from a finger or from a vein. The analysis is recommended to be performed on an empty stomach, preferably in the morning until nine o’clock. If this is not possible for some reason, the day should be planned so that you go to the laboratory at least four hours following eating. Blood can be given at any time of the day to detect multiple infections.
To the laboratory – on an empty stomach
Jana Osīte emphasizes that a mistake often made by patients is not following the nutritional recommendations before the analysis. There is still an important rule – most blood tests must be taken on an empty stomach to get a correct result, and what was consumed in the diet the day before going to the laboratory is also important.
“You should not eat, for example, fatty food the day before. You should also be careful of some medications that can affect the blood picture, so you should discuss them with your doctor,” says Jana Osīte and explains that some liquids contain chemicals that provoke the formation of various enzymes, starting metabolic processes, followed by their synthesis and breakdown. release of products into the blood.
A glass of mineral water? Thanks, next time!
Yes, even mineral water can affect the results of the analyses. “As we know, bubbles are made of carbon dioxide. There is an enzyme in our blood whose task is to ensure the conversion of carbon dioxide released during excessive breathing. It is important to understand that changes in the content and activity of respiratory enzymes affect blood biochemistry. This does not interfere with the general analysis, but it should be taken into account that mineral water also contains iron, sodium, magnesium, chlorine, calcium, sulfates, bicarbonates and other chemical elements, as a result of which blood biochemical indicators may be incorrect.”
Drinking a lot of tea makes it harder to take blood
It seems unbelievable, but it is true. Tea contains tannin, a substance that can cause an increase in blood viscosity, so drinking a large amount of this drink can really interfere with obtaining a blood sample.
Coffee – tone, without which you should do on the morning of the analysis
The main chemical reactions caused by the caffeine contained in coffee in the body are improving tone, activating brain activity and increasing efficiency. Habit and morning ritual are of course very powerful, but before going to the laboratory to give a blood test, you should give up a cup of coffee.
Juice affects blood sugar levels
Any fruit and vegetable juice, regardless of whether the juice is freshly squeezed or poured into a glass from a package, contains a lot of carbohydrates glucose and fructose. It is absorbed extremely quickly and affects the blood sugar level. For this reason, the analysis results will not be accurate.
Alcohol and tests – it’s not serious!
A good way to spoil the results of the analyzes is to go to give them following a good party with alcohol. It is worth knowing that the effect of ethyl alcohol on the body’s metabolic processes is even stronger than that of tannin or caffeine. In addition, alcoholic beverages also reduce the quality of blood clotting.
Green light – for a small amount of water
That’s right – pure water cannot affect the results of blood tests. It is allowed to drink it, but it is better – in small quantities. “Excessive water consumption can reduce the concentration of elements in the blood and also change the diagnostic results,” explains Jana Osīte.
If specific indicators are needed
If the doctor has ordered to determine other indicators in the blood, for example, insulin, C peptide, vitamin B12, glucose level, before taking the analysis, you should refrain from eating for at least eight hours, sometimes even longer, since the food taken can change the concentration of certain indicators in the blood. How to properly prepare for the transfer of the analysis, it is definitely recommended to ask the doctor who prescribes the referral.
Urine analysis. It is best in the morning
Jana Osīte explains: “Usually morning urine is used for analysis, but if necessary, any other can be used. You should avoid eating and drinking the night before taking the sample, and refrain from sexual intercourse for 12 hours. It should be noted that it is not desirable to collect the sample immediately following physical exertion. The most suitable time is before breakfast, at least four hours following the previous urination.”
A container is used to collect urine for analysis, which can be obtained from a laboratory or purchased at a pharmacy.
Sample collection rules
- Do not touch the body with the container.
- Observe hygiene. The urine sample must not be mixed with faeces or any other material.
- The sample should be taken to the laboratory as soon as possible. If this is not possible, it can be stored in a refrigerator at a temperature of + 2 to +8 °C for no longer than two hours.
- If urine collection tubes with preservatives are used, they may be stored under these conditions for up to 24 hours.
Important! Improper storage of the urine sample can significantly affect the results.
Sometimes urine must be collected around the clock
Sometimes, for example, to check the functional capacity of the kidneys, urine must be collected for 24 hours. “Dual urine collection begins by emptying the bladder immediately following waking up and recording the time. From now on, the urine continues to be collected throughout the day in one container, which is stored in a refrigerator (+ 4 to + 8 °C). This is a necessary prerequisite, because at room temperature, the content of glucose in the urine decreases significantly,” says the doctor. After collecting the urine, accurately measure the daily amount of urine to be recorded in the shipment, mix the urine thoroughly, pour 20 ml into the small urine container and take it to the laboratory as soon as possible. The rest of the urine can be discarded.
If urine tests are to be given to a small child, such as an infant, urine collection is facilitated by self-adhesive bags that can be purchased at a pharmacy. A urine sample can be collected from a supine patient using a catheter.
Feces – almost the entire menu
The laboratory doctor warns that food products can affect the results of the analysis, therefore, 48-72 hours before collecting the analysis material, you should avoid eating beets, carrots, broccoli, cucumbers, radishes, horseradish, meat (especially lightly heat-treated), fish, mushrooms, products with increased amounts of vitamin C, such as grapefruit.
A stool sample is collected with a special spoon, which can be purchased complete with a container at a laboratory or pharmacy. About 10-15 g of feces taken from the total mass at different places and depths are needed for a full analysis. The sample should not be taken following an enema, during and three days following menstruation, during hemorrhoids and other bleeding. It should be delivered to the laboratory on the same day.
Citizens between the ages of 50 and 74 can undergo a state-paid preventive test for bowel cancer (examination of hidden blood in the feces) once every two years. To receive a test paid for by the state and information regarding conducting the examination at home, you should contact your family doctor’s practice. “When performing this test, one must be careful – excessive alcohol consumption, as well as the use of aspirin or other medications can cause gastrointestinal irritation, due to which hidden blood can appear in the stool, so these substances must be stopped 48 hours before testing,” says the doctor. There are no dietary restrictions before testing.
To the laboratory – sputum
Usually, the first portion of sputum is sufficient for sputum analysis – the lung secretion that has accumulated during the night. To avoid contamination of the contents of the oral cavity, rinse the mouth with clean water before collecting sputum. Sputum is collected in a clean, dry container, which is tightly closed with a cap. Only the material that comes out when coughing is important for analysis. The sputum sample must be delivered to the laboratory within four hours. Until then, it is stored in a refrigerator at a temperature of +2 to +8 °C.
For examinations of the causative agent of tuberculosis, sputum is collected for 24 hours or one portion that comes out during coughing, using a sterile specimen collection container that can be obtained from a laboratory or pharmacy.
Only freshly collected sputum is used for microbiological examination.
The company’s performance has been evaluated, with Stella Lapiņa, the chairwoman of the board, being awarded the LR Cabinet of Ministers award for her contribution to the development of the healthcare industry.
“Central laboratory” accepts analysis samples in 79 branches, and samples for Covid-19 can be handed over to more than 10 Covid-19 analysis acceptance points throughout Latvia. More than 650 employees work in the laboratory.
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