What types of syringes and injection needles are there? Own business: production of disposable syringes. Technology and equipment for the production of syringes, cost calculation and documents for starting Types of medical syringes

Disposable syringes. Syringes were first invented in one thousand eight hundred and fifty-three. The syringe was invented by two people at the same time. Nowadays, not a single doctor or patient can do without a syringe. Using a syringe, you can collect blood, administer medications, and give various vaccinations. There are a large variety of disposable syringes. Two-piece syringes consist of a piston and a barrel. And three-component ones are distinguished by a soft piston. Three-component syringes are used more often in medicine. They are used by anesthesiologists, medical aid doctors, and therapists. They vary in size and connection to the needle.

Syringe sizes and their classifications:

From 0 to 1 ml. – used for precise administration of drugs in small volumes.

From 2 to 20 ml. – they are most often used for subcutaneous infections, also for intramuscular and intravenous infections.

From 30 to 100 ml. – connect them to catheter nozzles. They are very popular in medicine.

Syringes are also distinguished by connection type:

Luer, Luer Lock, Catheter, Integrated needle.

Luer connection - In this connection, the needle is placed on the syringe. Such compounds are used throughout medicine.

Luer Lock connection - with this connection the needle is simply screwed into the syringe. This connection is especially used when drugs are administered under the periosteum. Also when drawing blood. It is used by anesthesiologists, oncologists, and non-atologists. Also if you need to administer the medicine slowly, but over a long period of time.

Cathetor connection – these connections are very good. They are good for administering medications through catheters.

Integrated needle – this needle cannot be removed. It is inserted into the very center of the cylinder. When drugs are administered, their loss is minimal.

Insulin syringes – these syringes are intended for individual use. Medicines do not leak from such syringes.

Auto-disable syringes are invented for large injections. Injection needles are very sharp. They are reliable to use. Safe. The range of such needles is varied. Also, needles can be selected by age, gender, and body weight.

Insulin syringe. In such syringes the needles are fixed. They have a simply large assortment. Transparent cylinder. The scale is not erased. That is, you can always see the volume of blood or medication collected. The piston is rubber and thanks to this the medicine is administered smoothly. Without providing pain to the patient. The needle is the most important part in the syringe. These sharp needles have a triangular point. Thanks to this, the skin is pierced painlessly. The needles are made of high quality surgical steel. Their thickness is minimal, but they are very durable. There is a thin layer of silicone on top of the needle, this contributes to minimal friction between the tissue and the needle.

Several advantages of such syringes:

Thanks to the latex-free piston, no allergies are caused.
This syringe is specially designed for younger people.
It is good for pregnant women to use, because the thin needle will not cause harm.

Insulin plastic syringes can be used for approximately two days. In this case, the syringes should be covered with a cap. But after four or five injections, the needle becomes a little dull and you should no longer use them. Before administering the medicine, you must shake it so that no sediment remains.

If you have mixed the insulins correctly, then the dose you choose will have an even effect on glucose. First, the shortest-acting insulin is drawn into the syringe. Then mix it with intermediate-acting insulin. Afterwards you need to wait fifteen seconds. In order for insulin to accurately enter the skin. After this, you need to pull out the needle.

At the moment, 70% of syringes sold in Russia are imported. There will always be a demand for syringes, and if a domestic manufacturer appears in the region, they will most likely purchase syringes from him rather than from imported suppliers.

To produce syringes with an injection needle, you will need a lot of expensive equipment, and the total amount of investment required to start a business from scratch will be about 1 billion rubles. Some companies started by opening the production of disposable syringes without a needle, which saved money. When the business began to make a profit, they started producing a full set. Also, many people purchase imported needles for a complete set. It takes about 11-12 months to organize a syringe manufacturing business (purchase of equipment, staff training, etc.).

Syringe: types and structure

In medicine, a syringe has a wide range of uses: it is used for various injections, for drawing blood, and for suctioning pathological contents from cavities. The structure of a modern disposable syringe is two-component (cylinder, piston) and three-component (cylinder, piston, rubber tip, lubricated with liquid for better sliding along the cylinder).

Syringes come in different sizes:

small volume (0.3, 0.5 and 1 ml). Used in endocrinology (insulin syringes), phthisiology (tuberculin syringes), neonatology, for vaccination and conducting allergy intradermal tests.
standard volume (2, 3, 5, 10 and 20 ml). Used for subcutaneous, intramuscular and intravenous injections.
large volume (30, 50, 60 and 100 ml). Used for suctioning liquids, administering substances and rinsing.

The syringe has different tip locations on the cylinder:

coaxial (concentric). Positioned at the center of the cylinder. For syringe volume 1-11 ml.
eccentric. Side location. For syringes with a volume of 22 ml.

There are three types of needle attachment:

Luer - the needle is put on the cylinder.
Luer-Lock - the needle is screwed into the cylinder.
non-removable needle integrated into the cylinder body (usually needles with a volume of up to 1 ml).

Production technology

The production facility includes several departments: a cylinder and piston production line, warehouses where raw materials are stored and received.

Syringe cylinders and pistons are made from polymer raw materials (polyethylene, polypropylene) by casting on special machines equipped with molds. The raw materials are poured into a hopper, the machine melts the mass, and then forms the necessary parts of the syringe. After casting and cooling, a scale is applied to the cylinders using offset printing or silk-screen printing. Tips are put on the pistons, after which they are connected to the cylinders. The finished syringe is sterilized and packaged in blisters.

Equipment and raw materials

The production line for the production of syringes includes the following set of equipment:

casting machine (injection molding machine) - from 150 thousand rubles for a used one, from 1 to 2 million rubles for a new one;
molds (200 thousand rubles - 500 thousand rubles);
cooling machine - from 50 to 250 thousand rubles;
pneumatic or vacuum forming machine for packaging - from 60-90 thousand rubles;
offset printing machine – about 300 thousand rubles;
syringe assembly machine (up to 24,000 syringes/hour) – from 1 million rubles;
sterilizer – about 1 million rubles;

Total: about 4 million rubles.

Required raw materials:

polypropylene (30-75 rub/kg). The production of 3 million syringes per month will take about 6-7 tons of raw materials, the costs will be about 400 thousand rubles;
rubber/silicone for the piston collar (from 240 rubles/kg);
printing ink (3-4 tons per month);

Premises and staff

The production facility together with warehouses should have an area of 2-5 thousand square meters. m. (depending on production volumes), ceiling height - at least 6 meters, spans - 12 m. Naturally, communications must be carried out in the building and electricity must be connected. Location – no further than 500 meters from the nearest housing. Number of personnel on the production line:

raw material preparation area (transportation of raw materials to the casting area, reception) – 2 operators, 2-3 workers;
casting section (automatic line) – 1-2 craftsmen;
scale application area – 1-2 operators;
packaging section (automated) – 1-2 operators;
sterilization area – 1-2 operators;
quality control – 1 specialist;
warehousing – 5-10 workers;

Total: at least 15-20 people.

Requirements

The product must be tested by Rospotrebnadzor and receive a certificate of conformity. The required characteristics of the syringe and test methods are described in GOST R ISO 7886-4-2009.

Investments

The initial investment (if renting premises) will be about 7-8 million rubles. Monthly expenses are about 3 million, income – 3.5 – 6 million rubles. The cost of a syringe without a needle is 50 kopecks -2 rubles/piece.

Cherukhina Kristina
- portal of business plans and manuals

Let's talk about the types of syringes, without which medicine would remain at the embryonic stage. There are a number of diseases when the use of tablets and syrups is completely prohibited. This, for example, could be diseases of the gastrointestinal tract. And it happens that the disease has developed and progressed so quickly that the pills will act for a very long time and can be fatal. And the only chance to urgently save a person’s life is injections. At first, syringes were reusable (in the 19th century), which did not always make the procedure sterile. And since the demand for them was great, scientists came to the conclusion that it was necessary to make them disposable. This happened, but later, already in the 20th century.

A little about the invention of the syringe

The famous veterinarian Murdoch from New Zealand created the first disposable syringe and introduced it into use not only in animals, but also in people. At first, disposable instruments were two-component. Later they began to be created from three components.

All modern syringes are divided into several categories:

needle fastening,
design,
cylinder volume,
tip location.

Needle attachment There are three types to the cylinder:

non-removable (syringe volume 0.3-0.5 ml),
luer (from 1 ml to 100 ml),
Luer-lock (for machine-driven syringes or droppers).

By design devices are divided into two types:

two-component (this type is very outdated and the procedure is very painful due to the lack of a seal; the piston in the cylinder is not fixed and moves inside, creating vibrations of the needle);
three-component (a rubber seal has been added, which prevents plastic particles from getting under the skin, and also makes piercing the needle smooth, without picking inside the muscle).

By cylinder volume all syringes are divided into:

small (for insulin, for skin testing for allergies, for use in neonatology, as well as vaccination);
standard (volume from 2 ml to 22 ml, used for intramuscular and subcutaneous injections);
large (volume from 30 ml to 100 ml used for suctioning liquids and washing).

There are two cone-tip position:

eccentric (the position of the cone is shifted and such a syringe is used to draw blood, the tip is located in the side of the cylinder),
concentric (the tip is located directly in the center of the cylinder, such devices are suitable for conventional injections).

Expiration date of syringes

The service life of the device does not change at all depending on whether it is two- or three-component, or what volume it is. But the type of sterilization significantly affects its suitability. Depending on the type of sterilization, the period may vary from three to five years. During this time, it should remain sterile and non-toxic.

When the terms come to an end, you can continue to use it, but only if it was away from direct sunlight. If storage exceeds ten years, then the materials in it age, and in the case of injection, particles may get under the patient’s skin. It is also dangerous to use a syringe if it was stored in damaged packaging or without it at all. It is very important to observe the expiration date so as not to harm the patient.

Classification of disposable syringes

Simple disposable often used only for injections. They come in different sizes such as 2 ml, 3 ml, 5 ml, 10 ml, 20 ml and 50 ml. Nowadays, it is sold in separate packaging made of polyethylene and paper, hermetically sealed.

Syringe Janet. Of all the existing injection devices used in medicine, it is the largest. Its volume is 150 ml. It is often used to suction or introduce large amounts of fluid from or into the body. May not be used according to instructions. Often used as an enema. They can receive intravenous infusions. Before you start using it, it is very important to make sure it is sterile.

Insulin. Their volume is 1 ml. With this syringe, people suffering from diabetes mellitus inject doses of insulin into the body. The needle is designed in such a way that patients administer the drug themselves and the procedure is easier and painless.

All cylinders are marked not only with milliliters, but also with units (this is the unit for calculating the dose of insulin). 1 ml = 100 units. The special shape of the piston makes the administration of the drug as precise as possible. Regular ones are marked with 1 unit, children – 0.5 or 0.25 units. Once upon a time, insulin syringes with markings of 40 units were used. These are now out of use. Very often, a syringe pen is used to administer this medicine. Even though it is considered disposable, it can be used until the needle becomes dull. But this syringe is not so convenient if you use it for insulin in doses. The piston will be moved away from the cylinder and will become uncomfortable to wear.

Syringe tube. Almost every health worker who visits your home has it. It already contains medicine, which is absolutely sterile and is used once. They immediately formulate the required dose of medication for one dose. The drug is in a sealed container and is always stored in the bag of the health worker when leaving.

Self-locking. This type of syringe is mainly used for carrying out a large number of injections for the purpose of immunizing the population. The main task is to control the health worker and prevent them from using the same instrument twice. After use, the piston is blocked and repeated use is simply excluded. This not only makes it possible for someone to monitor the medical staff for fraud, but it is also much easier for the medical worker himself to figure out which syringe was used if it accidentally ends up in a box of new ones.

Classification of reusable syringes

Regular reusable. It was invented in the 19th century. In those days, disinfection was carried out only through sterilization. And that’s why they were made of heat-resistant glass that can withstand temperatures up to 200 degrees. The needle and piston were made of metal.

They were sold in special containers in brown paper called “kraft bags.” Due to constant boiling, the needles became dull. Before each use, they were rubbed with a special wire “mandrain” in order to make them sharper. And due to poor disinfection, these syringes transmitted a large number of diseases. Now these are no longer used and they have been replaced by reusable ones, but already improved by centuries and progress.

Syringe pen. This device has already been described above. Using a pen syringe, insulin is injected into the body of a person with diabetes. It looks a lot like a fountain pen. The needle is quite thin, just like in an insulin syringe. The only main difference is that the injection itself is much simpler. You simply press a button on the top of the body, then the mechanism is activated and a strictly marked dose of medicine flows out of the cartridge. But that doesn't mean all of it. There may still be some medication left in the cartridge for the next dose. There are pens with a removable needle, and others with a permanent one. The latter must be sterilized. If the needle is changed, this should be done about once a week.

Syringe dart. Often used in veterinary medicine. There are special guns for them that are filled with darts. It is used when it is necessary to put a wild animal to sleep for some time with a tranquilizer and from a long distance. You can also put a drug in it not only to euthanize the animal, but also for treatment.

Syringe gun. This device is designed for independent use. It is suitable for use with 5 ml syringes. This is the size that will fit snugly to the gun, not loosen, and will not damage the skin or muscle during a shot. Its inventor claims that the shot is very fast and accurate, and the patient feels no pain at all. The needle hits the target exactly and all that remains is to press the piston to inject the liquid.

Types of syringe needles

Studying the global issue of medicine and injections, you can understand that there are not only different types of injection syringes, but also the needles themselves. The relationship between a syringe and a needle, their correct selection, as well as the correct choice of device for a particular drug, significantly simplifies the treatment process and makes it much more comfortable. Medical needles are divided into two types:

injection (they are designed for introducing and removing fluid from the body, empty inside and absolutely sterile);
surgical (these are curved needles with an eye at one end, used for stitching tissue during operations).

In matters of treatment and the use of various injections, you must rely on your doctor. It is very important not to self-medicate unless you are an experienced doctor.

A disposable syringe consists, just like a glass one, of a cylinder and a piston rod (collapsible or non-dismountable). The cylinder has a Luer-type cone tip (Record syringes can be produced upon request, they are practically not produced), a finger rest and a graduated scale. The rod-piston assembly consists of a rod with a stop, a piston with a seal and a reference line.

Depending on the structure of the piston rod, the design of disposable syringes

are divided into 2-component (Fig.) and 3-component (Fig.). In 2-component syringes, the rod and piston are a single unit; in 3-component syringes, the rod and piston are separated. The main functional difference between these designs is the characteristics of lightness and smooth movement of the piston. Disposable syringes can also be coaxial and eccentric (Fig. 18), which is determined by the position of the cone tip.

Rice. 18. Disposable syringes, coaxial (1) and eccentric (2)

Fig. 19. Disposable eccentric syringes.

The capacity of syringes is determined by their purpose and ranges (GOST) from 1 to 50 ml. In practice, the range of volumes of disposable syringes ranges from 0.3 to 60 ml. Syringes volume 0.3; 0.5 and 1.0 ml are used for precise administration of medications (tuberculin, insulin, standard allergen extracts) in small volumes - from 0.01 ml.

The industry produced sterilizing cases for storing and sterilizing syringes. They were sometimes called syringe packs. They were very widespread in various field conditions. Today they have been replaced by disposable syringes, but you can still encounter them in your practice.

Fig.20. Sterilizer cases for storing and sterilizing glass syringes.

Medical needles

Piercing or piercing-cutting instruments in the form of a thin rod or tube with a pointed end. In addition, they produce special ligature needles .

Depending on the purpose, medical needles are divided into:

ü injection,

ü puncture biopsy,

ü surgical.

injection needles

Injection needles are intended for administering drug solutions, drawing blood from a vein or artery, and blood transfusion. They are used together with syringes, as well as systems for transfusion of liquids or blood. An injection needle is a narrow metal tube made of certain types of steel, one end of which is cut and sharpened, and the other is tightly attached to a short metal coupling for connection to a syringe or elastic tube (the internal diameter of the head opening for Record syringes is 2.75 mm, for Luer type syringes - 4 mm). Sterile disposable injection needles are becoming increasingly common. Their use dramatically reduces the risk of infectious complications, they are convenient and do not require prior sterilization. The main significant parameters of the needle are length, outer diameter, sharpening angle and puncture force. Needles have different lengths (from 16 to 90 mm) and diameters (from 0.4 to 2 mm):

ü for intradermal injection, a needle with a length of 16 mm and a diameter of 0.4 mm is used,

ü for subcutaneous injection, a needle with a length of 25 mm and a diameter of 0.6 mm is used,

ü for intravenous injection, a needle with a length of 40 mm and a diameter of 0.8 mm is used,

ü For intramuscular injection, a needle 60 mm long and 0.8-1 mm in diameter is used.

In practice, a needle of maximum length 38 (40) mm provides intramuscular injection of the drug into the area of the superolateral quadrant of the buttock in 15% of men and 5% of women. (rice.)

Rice. 21. Needles for injections, infusions, transfusions: a - injection needle (1 - needle tube, 2 - needle head, 3 - mandrin, 4 - dagger sharpening, 5 - spear sharpening, b - needle cut angle); b - needle with stop for intradermal injections; c - needle with safety bead; d - needle with side holes for air release; d - attachment to an injection needle for connection to blood transfusion systems, etc.; e - transition cannula for injection needles; g - Dufault needle for blood transfusion; h - needle for drawing blood.

The cutting angle of injection needles ranges from 15 to 45° depending on the task of execution:

ü 15-18° for injection needles,

ü 30° at needles for inserting catheters into a vein, for spinal puncture,

ü 30 and 45° for needles with a short bevel for introducing radiopaque agents

The needles have a spear- or dagger-shaped sharpening. The outer diameter of the needle ranges from 0.4 to 2 mm, length - from 16 to 150 mm. The needle number corresponds to its size (for example, No. 0840 means that the needle diameter is 0.8 mm, length is 40 mm).

Fig.22. A - disposable needles with

different designs of cannulas with a case.

B - various options for sharpening needles,

produced by industry.

An IV needle is cut at a 45° angle, while a hypodermic needle has a sharper bevel angle. The needles should be very sharp, without jagged edges. (Fig. 21). The needle point is sharpened in 3 planes (spear-shaped sharpening), which ensures that the piercing effect prevails over the cutting effect when piercing tissue. The protective cap protects the needle from external damage and ensures safety when handling it. On the packaging, the type of needle cut is indicated by a special symbol ©. In this case, the needle has a medium bevel length and is intended for intradermal administration of drugs.

The characteristics of the injection needle are important. The ease of tissue penetration (penetrating force), the accuracy of hitting certain anatomical structures, the stability of the needle position in the vessels, the degree of tissue trauma, and therefore the pain of the injection, depend on them. The listed characteristics of the needle in certain cases, along with the cost, determine the choice of the entire set (syringe + needle).

A good injection needle has the following requirements:

ü minimum force for puncture,

ü longitudinal resistance to bending (elasticity),

ü strength, stability of connections with the syringe,

ü minimal roughness of the outer surface and sharpening area.

Puncture force

The force required for puncture is determined by various factors, including design and manufacturing. This indicator depends on the shape and quality of the needle tip and cut, as well as on its diameter and special surface coating. A poor-quality cut can capture microfragments of the skin. With an increase in needle diameter from 0.5 mm (insulin syringe needle - orange cannula) to 0.8 mm (standard needle - green cannula), the puncture force increases by 1.5 times. Better glide of the needle at the moment of puncture is achieved by applying a silicone coating to the surface of the needle, which is used by most manufacturers, including large domestic ones.

Packaging of needles

The packaging of needles must provide:

ü maintaining the sterility of the contents when stored in dry, clean, properly ventilated areas;

ü minimal risk of contamination of the contents at the time of opening;

ü adequate protection of the contents under normal conditions of storage and transportation;

ü creating conditions under which an opened package cannot be resealed without much effort, and the fact of opening is obvious.

In addition to the primary packaging, there must be a secondary rigid one that protects the contents. On the packaging of needles, in addition to information about the manufacturer and supplier (name and trademark) and contents, they indicate: “best before..” (English - exp. date), and then the day, month and year of manufacture. Full details of the manufacturer or supplier are included on the secondary packaging. The packaging must remain intact during transportation (temperature from -50 to +50°C) in vehicles protected from precipitation and storage at temperatures from -5 to 40°C in heated and ventilated rooms. The packaging is sensitive to moisture. The susceptibility of domestic syringe packages to getting wet during short contact with water can be determined by paper density, print quality, and the presence of voluminous accompanying information. Domestic analogues of packaging are more resistant to moisture. Foreign-made syringe packages are more prone to getting wet.

When choosing injection devices, you should give preference to syringes in a package consisting of two parts, since when the paper part of the package is torn, fibers of the packaging paper are found on the syringe parts and the needle. If the package consists of two parts, you must follow the opening method indicated on it.

Intramuscular injections are one of the most common medical procedures. Most often, nurses encounter it in treatment rooms and intensive care units. They are the ones who know which syringe for intramuscular injection is best to choose, and what to focus on when choosing. The article reflects the experience of medical workers who have worked in treatment rooms for more than 15 years and performed several thousand intramuscular injections.

Syringe design

There are two main types of disposable syringes: two-component and three-component. The first type of syringes consists of a cylinder and a piston with a rod, made in one piece. The three-component syringe additionally uses a rubber seal, which is located at the end of the piston.

Most nurses do not even have a question about which syringes to choose - preference is given to 3-component ones. This is explained by the greater ease of sliding of the piston along the cylinder, which greatly facilitates injections. Some 2-component syringes are not inferior in smoothness to 3-component syringes, but this statement is only true for products produced by European manufacturers.

The disadvantages of 2-component syringes include the insufficient tightness of the piston to the cylinder, which does not exclude the possibility of drug leakage. It is especially unpleasant when an expensive drug leaks. This disadvantage is inherent in the cheapest syringes.

Important! Smoother administration of medications ensures less pain during the injection.

One of the disadvantages of 3-component syringes is the fact that the latex used in the manufacture of the seal can cause allergies in people with a predisposition. However, some manufacturers make seals from completely inert materials that do not contain latex; packages with such syringes are marked “Latex-free”.

Needle lock type

When buying a syringe for intramuscular injections, you should pay attention to the method of attaching the needle to the syringe. There are two main types:

Luer Slip - the needle is placed on the cannula of the syringe and is held on it due to a tight fit. For most injections this is sufficient. However, the disadvantage of this type of clamp is that the needle may jump off the cannula if the piston is pressed too hard. This kind of trouble occurs especially often when administering thick, oily medications.
Luer Lock - the needle is screwed into the lock along the thread. The likelihood of the needle slipping during injection is zero. Most nurses prefer to work with these syringes.

Some syringe models are sold with needles already attached to the cannula. When deciding how to choose the right syringe for injection, there is no fundamental difference between these models and the options with a separate syringe and needle. In any case, the nurse will need to make sure that the needle is placed securely.

Characteristics of injection needle

When choosing a syringe for intramuscular injections, special attention should be paid to the needle - its characteristics often determine how painful the injection will be. The following characteristics are important:

Needle diameter and length. For a patient of normal build, the optimal needle for intramuscular injection is a needle with a diameter of 0.8 mm and a length of 45-70 mm. You can determine the diameter by the color of the pavilion - the color marking of needles is carried out according to the global standard: green indicates that the needle has an outer diameter of 0.8 mm, and yellow - 0.9 mm. The length of the needle can be assessed visually. For obese people, it is better to take longer needles - at least 70 mm, since due to the severity of the subcutaneous tissue, there is a possibility that a short needle will not reach the muscles during injection.
Sharpening the needle tip. The most common type of sharpening of injection needles is flat. As a rule, injections with such needles are the most painful. Leaders in the production of medical consumables sell syringes with needles with lance-shaped or triangular sharpening - patients practically do not feel the moment of tissue puncture with such needles. This aspect is especially important when deciding how to choose a syringe for injection for a child.
Needle grinding. For better glide of the needle, it is treated (polished) with a silicone compound. Of course, an amateur will not be able to determine by the appearance of the needle whether it has been ground. To resolve this issue, you can ask the pharmacist for a certificate. If it mentions the ISO 7864 standard, then the needle is lubricated.

Considering the above characteristics, the image of the “ideal” syringe for intramuscular injection will be as follows: this is a three-component syringe with a Luer Lock fastening, with a needle ground according to the ISO 7864 standard with a triangular (lance-shaped) sharpening.

Which syringes have fewer complications?

The criteria for choosing a syringe listed above guide the patient on how comfortable the injection will be for him. The frequency of complications in most cases depends on the thoroughness of the injection technique. Complications after injections in the buttock (as the most common type of intramuscular injection):

infiltrates - formed due to too rapid administration of the drug, when administering cold drugs, when introducing drugs into the subcutaneous tissue (due to a short needle);
an abscess is the most unpleasant complication after an injection in the buttock, occurring most often when performing injections at home;
nerve damage - usually occurs in thin people and children when using needles that are too long;
hematomas - occur most often when using blunt needles;
needle breakage - often occurs due to a reflex contraction of the gluteal muscle, the main reason is a poor-quality needle (experienced nurses note that Chinese and Russian needles most often break, but in recent years domestic manufacturers have dealt with this problem).

Normally, there should be no air bubbles in the injection - their presence indicates a violation of the technique of drawing the medicine into the syringe. When they are detected, you need to wait until they unite into one large bubble and release the air through the needle.

Intramuscular injections with any syringe should be performed by a nurse! Performing this manipulation by a professional who has undergone special training allows you to almost completely eliminate the likelihood of complications from injections in the buttock.