Diagnostic value of a blood test for sterility. Why are blood cultures taken for sterility? A blood test for sterility, which shows

Blood for sterility is a test that allows you to determine the presence of bacteria in the blood. Sterile blood is the norm in the body, however, in some cases, bacteria and microbes disrupt this state, causing a decrease in immunity and the development of dangerous diseases. Sometimes doctors cannot determine the cause of a particular disease, and then blood cultures for sterility are necessary.

Why is an analysis ordered?

The main purpose of the study is to detect bacteremia. It can indicate several diseases:

• Meningitis;
• Tuberculosis;
• Purulent skin lesions;
• Osteomyelitis;
• Endocarditis;
• Sepsis.

As a result of the study, infections of the genus staphylococcal, streptococcal, as well as yeast fungi, enterobacteria, Pseudomonas aeruginosa and some others can be detected. Bacteriological culture is an effective method for determining the type of microorganism-causative agent. The only drawback of the study is considered to be a long time for obtaining results - from 3 to 14 days. During this time, the infection can spread even more in the body, causing irreversible pathological processes. That is why it is important to diagnose and prescribe drug therapy as early as possible.

Most often, a blood test for sterility is prescribed to patients who have a high temperature for a long time without apparent causes and other symptoms. Persons with artificial heart valves, as well as after surgical operations and if blood poisoning is suspected, are also subject to mandatory research. Prolonged catherization is a reason to prescribe a sterility test, because. possible presence of infections of various types (intestinal, streptococcus, staphylococcus aureus). Persons with HIV infection are at risk, because at this time, immunity falls, the body becomes susceptible to bacteria and infections of various etiologies. Mycobacterium tuberculosis is often found in such patients.

How to properly prepare

The most informative analysis is obtained if you donate blood several times. In addition, a certain microorganism should be detected not only in the blood, but also in other biological materials (urine, sputum, etc.). At the same time, accuracy is achieved by parallel carrying out bakposev on different nutrient media.

There are several rules that must be observed during preparation for donating blood for sterility. First of all, it is necessary to give up alcohol 2-3 days before the study. During this period, it is not recommended to eat fatty, spicy, fried foods. Preparation also includes quitting smoking a few hours before blood sampling. Doctors recommend taking most tests on an empty stomach, so the last meal should be 8 hours before the analysis. If the patient is taking any medications, this factor should be taken into account separately by the doctor who prescribes the study.

Blood sampling procedure

For a blood test for sterility and blood culture, venous blood from the elbow is needed. In young children, there may be other places on the body from which it will be easier to take a sample for analysis. It is best to test immediately before therapy so that the result is more accurate. The rules for the analysis are the obligatory sterility of the procedure. It is necessary to carefully treat the injection site with antibacterial agents - alcohol and iodine, and also monitor the sterility of a disposable syringe. In order to increase the reliability of the analysis, patients are sometimes injected with epinephrine under the skin.

This activates pathogens, and it becomes easier to detect them in the body.

A small amount of the sample (10 ml) is placed in a sterile 100 ml vial with a special nutrient liquid. When transfusing biological material into a vial, a burning spirit lamp is used to avoid viruses from the external environment. Next, the vial is carefully sealed and transported to the laboratory. There they carry out a tank sowing the sample. The final blood test for sterility will be ready in 10 days, and the first results can be obtained after 3 days. Infection can be diagnosed if the culture for sterility showed less than 100%.

Bacposev shows the bacteria contained in the blood, which after a certain time become visible with a microscope. The detected type of pathogen helps to determine the stage of the patient's disease. Also, the identified type of bacteria is tested for sensitivity to antibiotics. For this, a so-called Petri dish is used. This helps the doctor prescribe effective medications. In the sample where the growth of colonies of microorganisms is not observed after contact with the antibacterial drug, it can be argued that it has a successful effect.

Despite the fact that a blood test for sterility is a rather rare study, and is prescribed only if a serious illness is suspected, you can donate blood for culture in almost any laboratory. To do this, it is enough to know how to prepare for donating blood for sowing, as well as get a referral from your doctor. Most often, the blood is sterile, but there are cases of infection that require immediate treatment. The doctor needs to have reliable test results in hand in order to prescribe effective drugs.

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Blood culture for sterility is a microbiological method for examining blood to detect infection in it and identify the causative agent of the disease. If necessary, the study is supplemented by an antibiogram, which determines the sensitivity of the pathogen to antibacterial drugs. For a more accurate diagnosis, blood cultures for sterility can be performed 2 or 3 times.

Normally, human blood is sterile, but with some infectious diseases, bacteria and fungi can enter the bloodstream and develop bacteremia and fungemia. Most often they are caused by a severe and aggressive course of infection or a decrease in immunity (for example, with, etc.).

In what cases can a doctor prescribe a blood culture for sterility? How to prepare for this study? How is the analysis performed? What is the cost of research? You will get answers to these questions by reading this article.

Indications

Indications for the appointment of blood culture for sterility may be the following clinical cases:

• fever of unknown origin for more than 5 days;
• suspicion of development;
• infectious;
• infectious arthritis;
• moderate and severe severity;
• some infectious diseases: and, paratyphoid, brucellosis, anthrax, plague;
• long-term venous catheterization;
• the presence of artificial heart valves.

How to prepare for research

Blood sampling for research should be carried out before taking antibiotics or after the maximum elimination of these drugs from the body. The analysis should be scheduled on days of maximum temperature rise.

• for 2-3 days to refuse to take alcoholic beverages;
• 2 days before the procedure, do not take spicy, fatty and fried foods;
• on the day of the study, refuse to eat and drink until blood sampling;
• do not smoke a few hours before the study.

How blood is drawn

The sampling of material for research is carried out in a laboratory or manipulation room in compliance with the rules of asepsis. For blood sampling, a disposable syringe and needle are used. It is strictly forbidden to take blood from intravenous catheters (exceptions are cases when it is necessary to identify a catheter infection). Sometimes, before taking the material, to increase the reliability of the study, it is recommended to administer a solution of Adrenaline subcutaneously, after which pathogens are released into the blood.

The skin puncture site is treated with 2% iodine solution, and after 1-2 minutes the iodine is removed with 70% alcohol. The cap of the sterile culture medium vial is also treated with 70% alcohol. Before performing the puncture, the skin must be dry. In adults, blood is taken from the cubital vein, in children - from the finger.

After vein puncture, 10 ml of blood is drawn into the syringe for analysis. The needle is removed from the vein and the puncture site is re-treated with an antiseptic.

Before the introduction of the obtained blood into the vial, the needle is changed to a sterile one and the material with the culture medium is poured into a container over a burning spirit lamp. It is strictly forbidden to remove the lid from the container.

After taking the material, the vial is labeled (the form should indicate the patient's data, the diagnosis and information about the antibiotics taken, if they are prescribed before blood sampling, the date and time of sampling) and sent to the laboratory in a thermostat with a temperature of 37 ° C.

How the analysis is done

In the laboratory, blood for seeding for sterility is placed in a thermostat and kept at a temperature of 37-38 ° C for several days. After this time, colonies of bacteria appear on the surface of the nutrient medium, which can be identified under a microscope. Preliminary results can be obtained after 3 days, final results after 10 days.

After isolating the culture of the pathogen, its sensitivity to antibiotics is determined. To do this, microorganisms are subcultured to another medium in a Petri dish, along the circumference of which disks moistened with antibacterial agents are placed. The material is placed in a thermostat and after a few days the intensity of bacterial growth to a particular drug is monitored.

results

The results of the analysis should be interpreted by the attending physician. Normally, microorganisms are not detected in the blood. In the presence of a pathogen in the blood, a monoculture (one microorganism) or more than one type of bacteria is detected.

Research cost

In state laboratories, a blood test for sterility is performed free of charge. The price of blood culture for sterility in private institutions depends on the laboratory in which the study is carried out. The cost of analysis can range from 700 to 3300 rubles.

Which doctor to contact

With prolonged fever of unknown origin, it is best to seek a referral for this analysis to an infectious disease specialist. The doctor will not only be able to interpret the results, but also make a diagnosis and prescribe the most correct treatment. Also, blood culture for sterility is widely used in surgery, cardiac surgery, orthopedics, neurology and other fields of medicine.

The specialist talks about blood culture for sterility:

A blood test for sterility allows you to detect the presence of harmful bacteria in the bloodstream, indicating ongoing pathological processes.

It is indicated for people with reduced immunity, patients after surgical interventions or with sudden temperature fluctuations of unknown etiology.

Also, a blood test for sterility may be prescribed if sepsis or meningitis is suspected.

It should be carried out periodically as a preventive measure. Bakposev is used for diagnostic purposes, as well as to detect sensitivity to antibiotics or correct the prescribed course of therapy.

The main indication for this type of analysis is the need to detect pathogenic microbes in the blood.

In a healthy state, the blood should be sterile, and it will not contain pathogenic bacteria.

The analysis is aimed at identifying streptococci, Pseudomonas aeruginosa, Staphylococcus aureus, yeast fungi and enterobacteria, which in a normal state the patient's immunity itself would not allow to spread.

But, for example, in the case of surgical interventions, protracted illnesses, or with weakened protective functions of the body, these bacteria can multiply uncontrollably and cause significant harm to a person.

Therefore, for example, people with HIV need to periodically undergo such examinations for preventive purposes.

For example, it is not uncommon for people with immunodeficiency to become carriers of mycobacterium tuberculosis, precisely because of the inability of the body to cope with external attacks on its own, while a person with uncompromised immunity will cope well with such difficulties.

Some bacteria are difficult to diagnose and can only be detected during multiple studies (Staphylococcus epidermidis).

What will this analysis show?

During infectious diseases, pathogenic microflora, entering the bloodstream, can spread throughout the body, capturing new organs located far from the original localization of pathogenic processes.

The very presence of such microorganisms in the blood signals that the disease is already at a fairly advanced stage.

The presence of pathogens in the bloodstream may be accompanied by high fever and an increase in the content of lymphocytes in the blood.

Spreading throughout the body, the bacteria will affect the organ systems, which will primarily affect the cardiovascular system and affect the work of the heart, causing various disorders.

Blood culture for sterility makes it possible to determine meningitis, endocarditis, pyoderma, osteomyelitis or sepsis.

With this analysis, you can identify the exact type of pathogenic bacteria and select the appropriate antibiotic.

In the study of microorganisms, the specialist determines not only their type, but also predicts the possible consequences of infection, and also carefully considers the process of therapy, revealing the pathogenic effect of microbes on different organ systems.

Based on all the studies and their thorough analysis, the doctor determines the course of treatment, individual for each patient, and, if necessary, can also prescribe additional diagnostic procedures, for example, if a person is infected with microorganisms that are not detected from the first tests, or to clarify how far he has gone the process of spreading bacteria, and to determine the degree of damage by them to certain organ systems.

Bacteria that make a mess in the human body will not necessarily be pathogenic.

Microorganisms of this type are divided into pathogenic and conditionally pathogenic. They differ in that pathogenic ones, even in small quantities, can already cause undesirable consequences and provoke a disease.

Opportunistic bacteria can be in small populations in the body of each person, which will be considered the norm.

With a decrease in immunity or under other favorable conditions for them, these microbes will begin to actively multiply and capture new organs, which will just cause pathological reactions.

Opportunistic organisms can provoke sudden temperature jumps of "unexplained" etiology, playing the role of a time bomb.

How to pass the analysis?

Preparation for such an analysis is considered a slight fasting and a simple diet. As before most of these procedures, at least 8 hours must pass between the last meal and blood sampling, so such tests are usually prescribed in the morning.

The diet consists in exclusion from the diet 2-3 days before the analysis of alcohol and fatty foods. At a minimum, you should not consume the above products at least a day before donating blood.

Blood for analysis is usually taken from a vein. The exception is small children, in whom it is easier to take material for research from a finger.

Before the injection, the puncture site must be treated with a disinfectant. For analysis, specialists always use disposable syringes. The study requires 5-10 ml of blood.

To increase the accuracy of the diagnosis, the doctor may prescribe an injection of adrenaline.

This is done in order to cause contraction of the spleen, as a result of which microorganisms in large quantities (if any) are released into the bloodstream. A similar injection is given 20 minutes before blood sampling.

After the blood donation procedure for bacteriological culture, the resulting material is placed in a vial with a special nutrient medium, after which it is subjected to a thorough analysis within 10 days.

The first preliminary results of the studies can be obtained within 3 days after blood sampling, and the final analysis will be ready after 10 days.

The blood sterility test is an accurate diagnostic tool that, in the right hands, will help to identify and cure the hidden causes of complex diseases.

On its basis, effective drugs are selected, and the course of the entire treatment is predicted.

A blood test for sterility, which is also called a culture, or a culture tank, allows you to identify the presence of pathogenic microflora in it.

Normally, the blood of a healthy adult is sterile. If, after taking the analysis, the microflora was detected, then this means that the person is seriously ill and needs adequate, comprehensive treatment using antibiotics.

With the help of this method, it is established whether a serious pathological process is really taking place, and based on the data obtained, adequate methods of therapy are selected.

Indications for performing a bacteriological analysis to determine the sterility of blood are:

• suspected infective endocarditis, osteomyelitis, meningitis;
• suspected sepsis, including in newborns;
• furunculosis is not a direct indication for this study, but if purulent rashes cover a large area of ​​the body, are located on the face, in close proximity to the brain, the risk of developing sepsis or meningitis increases, and this is already a reason to donate blood for sterility;
• specific symptoms in a patient that are not amenable to standard treatment regimens, while it is not possible to determine the causes of the pathological process;
• complications after unsuccessful surgery;
• periodic increase in temperature in the absence of obvious reasons;
• the patient's body has an implant in direct contact with biological media - for example, an artificial myocardial valve;
• unconfirmed oncological diseases;
• HIV and AIDS - since the immune system does not function fully, it is necessary to regularly conduct a routine blood test for the early detection of a possible infection, in particular, tuberculosis.

It is also recommended to do it if you want to install an internal catheter for a long time. In this case, the doctor also needs to make sure that there is no infection, and if it is, identify its pathogen and eliminate it.

Sometimes an analysis is also prescribed for pregnant women, since during the period of bearing a child, a woman's immunity decreases for natural reasons, she becomes more vulnerable to infections of various kinds. The rules for preparing for the event and the execution algorithm are the same.

On a note: do not confuse the microbiological study of blood for sterility and blood culture. These are two different tests, the main difference of which is in scale. The first analysis shows whether bacteria are present at all in the patient's body. And blood culture reveals the characteristics of a particular type of microbes and allows you to control their activity.

How to prepare?

The results of microbiological testing are influenced by internal and external factors, so it is important to minimize their impact through proper preparation.

Usually, the doctor or nurse always informs how to properly prepare for a particular analysis, and in private clinics you can even get a special memo.

But the main points of proper preparation are always the same:

1. Three days before the scheduled date of blood sampling, you should stop drinking alcohol in any form and taking any medications. If the patient must take medication constantly due to a chronic pathology (for example, diabetes mellitus), they cannot be canceled on their own, a doctor's consultation is necessary. Usually the dosage is reduced by 3-5 days to the minimum safe.
2. And also, three days before the appointed date, you should refuse fried, fatty, salty with a lot of spices, high-calorie sweets.
3. The analysis should be taken strictly on an empty stomach. Therefore, 8 hours before the procedure, food intake is stopped.
4. Drinking, eating and smoking is prohibited on the day of the event. If for some reason the patient violated these rules, then the delivery of the biomaterial is postponed.

In the event that the patient violated the rules and kept silent about it, then the analysis will not show a reliable picture and testing will have to be done again.

How is blood drawn?

There are strict rules for blood sampling for bakposev, the violation of which will lead to a distortion of the results.

The sampling algorithm is as follows:

1. The medical worker prepares in advance a syringe with a disposable needle and a container for storing and transporting the collected biomaterial.
2. A tourniquet is applied to the patient's forearm - it does not matter which hand to take blood from, right or left. The physician will assess the condition of the vein.
3. Then, the inner surface of the elbow bend is disinfected with an alcohol solution.
4. After that, a direct sampling is carried out - in total, no more than 10 ml of venous blood is required.
5. From the syringe, it is immediately poured into a test tube with a nutrient medium, which will not allow changes in its composition.
6. To preserve the purity of the obtained raw materials, manipulations are performed over the burner, then the container is hermetically sealed with a rubber stopper and transferred to a container until laboratory tests are carried out.
7. In some cases, adrenaline is injected intravenously before taking blood for analysis. This substance causes spasm of the spleen and the release of bacteria, which helps to determine their maximum number.

Attention! Blood sampling for such an analysis in an infant has its own characteristics. The difference is that the biomaterial is taken from the finger or heel in a volume not exceeding 5 ml.

How is the analysis carried out?

Blood culture for sterility is carried out in several stages.

First, the physician will sow the resulting biomaterial into a nutrient medium, then place the samples in a thermostat and keep them at 37-38 degrees for several days. On the second or third day, colonies of bacteria will be visible on the surface with the naked eye. Visually, the laboratory assistant will be able to determine which species the bacteria belong to.

After that, the microorganisms are re-sown in a special device - a Petri dish. Paper discs soaked in various antibacterial preparations are placed around the circumference. The cup is placed again in a thermostat and aged for several more days.

This method establishes the sensitivity of microbes to antibiotics. That disk, on the surface of which no colonies of microbes are found, contains a medicine that can destroy pathogenic microflora. Based on the results obtained, an antibiogram is compiled, which will be used in further treatment.

The biphasic system for detecting blood cultures involves the use of a dual culture medium. Usually it is a liquid medium, represented by broth, and a solid medium, represented by agar. The fact is that some microorganisms show active growth in a solid environment, while others spend most of their lives in a liquid substance. Therefore, to ensure the rapid growth of bacteria, a two-phase medium is used.

On the video you can learn more about the analysis and the procedure for its implementation:

What does the analysis show and how is the decoding carried out?

As mentioned above, this analysis will show the presence of pathogenic microflora in the biomaterial and its type.

Specifically, it detects pathogenic microorganisms of the following groups:

• staphylococci;
• streptococci;
• Pseudomonas aeruginosa;
• enterococci;
• gonococci;
• mold spores;
• yeast fungi;

Even in a private laboratory equipped with all the necessary modern equipment, the analysis is done for at least 10 days. A positive or negative result will be known in two or three days, but in order to accurately identify the types of pathogenic microflora, its activity, it will be necessary to alternately introduce various reagents and components and wait for the reaction.

Such periods are necessary so that the bacteria have time to grow. The rate of germination of pathogenic microorganisms depends largely on their type. If the patient has severe symptoms of an acute inflammatory process, the doctor will prescribe broad-spectrum antibacterial drugs after blood sampling. But a truly effective, adequate treatment can only be selected after complete results indicating the causative agent of the infection are obtained.

Deciphering and setting the final diagnosis is carried out exclusively by a doctor.

Where to donate and how much?

The cost of the study is formed based on the level of the clinic and laboratory in which the analysis is performed. In the district clinic, in the direction of a doctor, this procedure is performed completely free of charge - provided that the local laboratory has the necessary tools and materials.

The cost in private clinics will depend on the level of the medical institution and the examination techniques used (what media are used). The average price of this analysis in the territory of the Russian Federation is 500 - 600 rubles. In the capital and large cities, the cost can increase up to 700 rubles.

Summarizing

Conducting a detailed blood test for sterility is recommended if a bacterial infection is suspected, this is not a mandatory study.

With the help of analysis, the presence or absence of pathogenic microorganisms in human blood is first established, then their type and activity. Also, blood is donated to check the patient's sensitivity to certain antibacterial drugs and draw up an effective treatment regimen.

The reliability of the results, subject to all the rules of preparation, sampling and laboratory research, is 95%.

Rinse the stomach of a patient with PTI

At the first signs of food poisoning (nausea, vomiting, abdominal pain, tenesmus, diarrhea), the patient must wash the stomach, asking him to drink liquid or introducing it into the stomach through a tube. The procedure can be repeated at a later date with ongoing nausea and vomiting. For this purpose, use a 2% solution of sodium bicarbonate, a weak solution of potassium permanganate or ordinary boiled water. Washing is carried out until the washing water becomes clean, without lumps of undigested food and mucus. Frequent vomiting and loose stools lead to dehydration of the body, so the patient, depending on the severity of his condition, is prescribed rehydration treatment of food poisoning in children using rehydron, quartasol, trisol orally. Infusion rehydration therapy is indicated in more severe cases, with toxicosis with exicosis, and in this case, a 5% glucose solution, saline solutions, Ringer-Locke solution are prescribed. Detoxification therapy includes the appointment of Hemodez, Polyglucin, Reopoliglyukin, which improve blood circulation and relieve symptoms of intoxication. Antipyretic and anticonvulsants, glucocorticoids are also prescribed. With a strong pain syndrome, antispasmodics are prescribed.

nutritional features of infectious patients

Basic rules for therapeutic nutrition of an infectious patient

The founder of Russian dietology, M. I. Pevzner, developed diet No. 13 for infectious patients, and recommended that the following rules be followed when compiling a diet for an infectious patient:

A febrile patient should not be allowed to starve. He should receive enough food, but in small portions at a time.

Any overfeeding is contraindicated, even if the patient has an appetite.

If possible, food that mechanically strongly irritates the digestive organs should be excluded from the diet.

It is necessary to monitor the function of the excretory organs and, in case of constipation, include in the diet foods that act in a laxative way (sugar, honey, juices of raw vegetables, fruits and berries), and in case of diarrhea, exclude milk in its pure form, cold drinks and limit the amount of sugar.

With renal symptoms, it is necessary to exclude strong broths, extractives, spices from the diet.

It is necessary to take into account the state of the patient's nervous system, allowing the introduction into the diet of only a small amount of nutrients that irritate the nervous system (strong coffee, tea, very strong broth), or even completely excluding them.

In acute infections, the body's need for vitamins increases significantly. Of particular value are vitamins, which in one way or another affect the state of immunity. The richest in vitamin C are rose hips, black currants, citrus fruits, and sea buckthorn. Food sources of vitamin A: liver, granular beluga caviar, egg yolk, butter, hard cheeses. Vitamin B2 (riboflavin) is found in large quantities in offal, yeast, almonds, cheeses, eggs, cottage cheese. Vitamin B6 (pyridoxine) is found in offal, meat, beans, soybeans, rice, millet, potatoes. D improves the state of antituberculous and antifungal immunity. Food sources of vitamin D: fish and marine animal liver oil, salmon, herring, mackerel, caviar, tuna, egg, cream, sour cream.

Among microelements, the most important for the state of the immune system is zinc, the deficiency of which develops in enteritis, especially in patients who abuse alcohol. Food sources of zinc: shellfish, mushrooms, egg yolk, liver, meat. Legumes, sesame, peanuts also have a lot of zinc, but it is associated with phytic acid. The daily requirement for zinc is 15–25 mg.

Stages of diet therapy for an infectious disease

Against the background of high fever, it is quite acceptable to drink thirst-quenching drinks for 1-2 days, you should not force the patient to eat. If fever persists for more than 5–7 days, then enteral or parenteral nutrition should be prescribed.

With the improvement of the patient's condition after a drop in body temperature, an increase in appetite is often noted. However, one should not strive to fully satisfy it from the very beginning, since in the first 3-4 days temperature fluctuations are noted for some time, the production of enzymes of the gastrointestinal tract is disrupted. That is why in these 3-4 days you should not drastically expand the diet used.

With further expansion of the diet, the greatest attention should be paid to replenishing protein and vitamin deficiencies. Either diet No. 11 or diet No. 15 is used. The amount of protein in the diet should be 1.5 g / kg of ideal body weight, while the quota of fats and carbohydrates corresponds to the norms of rational nutrition. Convalescents are prescribed a diet with a restriction of products that stimulate the central nervous system (strong coffee, tea, strong broths, spices, chocolate) and products containing coarse fiber and essential oils (rutabaga, turnip, garlic, radish, radish). Cakes, pastries, shortbread dough products are not shown. All types of cooking are allowed: boiling, stewing, baking and frying without breading. Diet 3-4 times a day.

Sometimes in convalescents, against the background of a rapid expansion of the diet, dyspeptic symptoms may occur. In this case, it is necessary to appoint a fasting day (boiled vegetables without salt and oil, baked apples) and check whether the diet is correct, whether the patient has concomitant chronic diseases of the digestive system, and, if necessary, make appropriate adjustments.

Blood sampling for typhoid fever

Blood sampling technique for culture. With strict observance of sterility, draw 5-10 cm3 of blood from the cubital vein into the Record or Luer syringe, remove the needle with tweezers, burn the cannula of the syringe on an alcohol flame and then pour the blood into the flask with the medium; the neck of the flask and the cork before closing, burn. Either broth or bile (50-100 cm3 of medium) is used as a nutrient medium. Technique of blood sampling for agglutination (Vidal reaction). From the pulp of the finger, pump 1.5-2 cm3 of blood into a sterile Pasteur pipette and, after filling, seal or draw 3-5 cm3 of blood from the cubital vein with a syringe, which is then poured into a sterile test tube. Keep the collected blood in a cool place. If necessary, you can use filter paper, for which 2-3 falling drops of blood are collected on a piece of paper 5 × 10 cm in size, dried in air and sent in a sealed envelope for analysis to the laboratory. Stool collection technique. Collection utensils (vessels, jars, etc.) should not be chemically treated, but only boiled. To better preserve the viability of microbes, it is recommended to mix feces with an equal volume of preservative (30% glycerol solution in saline).

Rules for sampling and blood culture for sterility and blood culture

Produced with typhoid-paratyphoid diseases, sepsis, meningococcal infection or other infections accompanied by fever, and throughout the entire febrile period of the disease, but better in the initial period or at the height of the disease (with severe bacteremia). For research, blood is taken from the vein of the elbow bend; in young children, blood is taken in a smaller amount from the earlobe, heel, and finger. Blood samples are taken after careful processing of the skin in compliance with the rules of asepsis, with a disposable sterile syringe. Sowing on nutrient media of sterile material (blood or other fluids containing microbes in healthy individuals) is also best done at the patient's bedside, or placed in a sterile container containing substances that prevent blood clotting 0.3% sodium citrate solution, 0.1% solution sodium oxalate). Usually take 5-10 ml of blood and inoculate into a vial containing 50-100 ml of medium. To do this, use for a vial with a nutrient medium (one for aerobes, the other for anaerobes). Blood cultures are performed on liquid nutrient media - 10% bile broth, 1% sugar broth, two-phase medium, as well as liquid and semi-liquid media for the cultivation of anaerobes at a dilution of 1:10. Vials with a nutrient medium are obtained in the laboratory; blood transfusion from a syringe into a vial must be performed over the flame of an alcohol lamp, after removing the needle. The culture bottle is sent to the laboratory, and in the evening and at night it is placed in a thermostat. It is important for the student to remember that the earlier from the onset of the disease, sowing is done. The more likely you are to get a positive result. And, conversely, the later the blood is taken, the less the pathogen is in it and positive results are obtained less frequently. And at normal temperatures - very rarely. You should know that in order to increase the number of positive blood culture results, it is recommended, in the absence of contraindications, to inject 1 ml of a 0.1% adrenaline solution subcutaneously in 15-20 minutes for blood sampling, which helps to reduce the spleen and release pathogens into the bloodstream (for example, with typhoid paratyphoid diseases) The preliminary result of sowing in typhoid-paratyphoid diseases is obtained after 2-3 days, and the final result after 7-10 days. It should be remembered that an increase in the frequency of blood cultures (three days in a row at a rise in temperature) significantly increases the frequency of isolation of microbes from the blood. In treated patients, blood for culture should be taken 5-6 times.

Lumbar Puncture performed by a doctor.

The nurse carries out: - preparation of tools; - preparation of the patient; - assistance to the doctor during the manipulation; - ensuring proper care of the patient after the puncture.

The purpose of the lumbar puncture is therapeutic and diagnostic.

Equipment. Sterile cotton balls, tweezers, 3% alcohol solution of iodine (iodinol), syringe 2.0 ml or 5.0 ml, two needles, 0.5% novocaine solution, lumbar puncture needle with mandrel, sterile test tubes, alcohol, sterile wipes , adhesive plaster, sterile rubber gloves, referral forms to the clinical and bacteriological laboratory.

1. The patient is placed in a sitting position, leaning forward, or lying on his side with his knees brought to his stomach.

2. Disinfect hands, put on sterile rubber gloves.

3. The puncture site (the point between the fourth and fifth lumbar vertebrae) and the surrounding area should be treated with an alcoholic solution of iodine (iodinol).

4. Anesthetize the skin with novocaine.

5. Perform a lumbar puncture: insert a needle with a mandrel into a point between the spinous processes of the fourth and fifth lumbar vertebrae.

6. Remove the mandrin (liquid should flow from the needle in a stream or drip) and substitute a sterile test tube. Collect the required amount of fluid for the study.

7. Insert the mandrin into the needle and carefully remove the needle.

8. Treat the puncture site and apply a sterile dressing.

Note: - the patient is transported to the ward in a horizontal position, lying on his stomach, on a stretcher; - the first 2-3 hours the patient should lie on his stomach without a pillow; - Strict bed rest is required during the day.