Central vein catheterization technique

A central venous catheter (CVC) is not required for patients in an awake state with stable blood circulation and for patients not receiving high osmolarity solutions. Before placing such a catheter, it is necessary to weigh all possible complications and risks. In this article, we will consider how the central vein is catheterized.

Choosing an installation location

When choosing a place for the installation of a catheter (puncture), the experience of a medical professional is taken into account, first of all. Sometimes the type of surgical intervention, the nature of the damage and the anatomical features are taken into account. In particular, for male patients, a catheter is placed in the subclavian vein (since they have a beard). If the patient has high intracranial pressure, the catheter should not be placed in the jugular vein, as this may impede the outflow of blood.

The axillary, medial and lateral saphenous veins of the hands, in which the installation of a central catheter is also possible, are considered alternative places for puncture. PICC catheters are in a special category. They are installed in the vein of the shoulder under the control of ultrasound and may not change for several months, representing, in fact, an alternative version of the port. Complications of a specific type are thrombosis and thrombophlebitis.

Indications

Catheterization of the central vein is performed according to the following indications:

• The need for the introduction of hyperosmolar solutions to the patient (more than 600 mosm / l).
• Hemodynamic control - measurement of central venous pressure (CVP), hemodynamic monitoring of PICCO. Only the CVP measurement is not an indication for catheter placement, since the measurements do not give an accurate result.
• Measurement of the level of blood saturation with carbon dioxide (in individual cases).
• The use of catecholamines and other substances that irritate veins.
• Long, more than 10 days, infusion treatment.
• Venous dialysis or venous hemofiltration.
• The appointment of infusion therapy in poor condition of the peripheral veins.

Contraindications

Contraindications to the installation of a catheter are:

• Infectious lesion in the puncture area.
• Vein thrombosis in which a catheter is planned to be inserted.
• Disturbed coagulation (condition after systemic failure, anticoagulation). In this case, a catheter can be inserted into peripheral veins on the arms or thigh.

Site Selection and Precautions

Before catheterization of the central vein, some rules must be observed:

• Precautions: the use of sterile gloves, a mask, a cap, a sterile gown and napkins, special attention should be paid to disinfection of the skin.
• Patient posture: the most optimal option is head down, as this facilitates the insertion of a catheter into the jugular and subclavian vein. It also reduces the risk of developing pulmonary embolism. However, it should be borne in mind that such a position of the body can provoke an increase in intracranial pressure. Seldinger’s central venous catheterization kit is discussed below.

Limitations

Choosing a puncture site is an important step in the procedure and involves the following restrictions:

• An alternative to the method of orientation by anatomical features is puncture of the jugular and subclavian veins under 1/3-control. This method visualizes the anatomical features and reduces the risk of complications, such as an erroneous position of the catheter or incorrect puncture (with a hematoma).
• Local anesthetization. If the patient is conscious, then before the procedure a mild anesthesia is administered, in some cases mild sedation with a midazolam injection.
• Venous puncture. If we are talking about the external, anterior or internal jugular vein, then the puncture is performed by a syringe filled with half-saline solution. The CVC in this case is established by the Seldinger method. If it is intended to be inserted into the subclavian vein, the j-shaped conductor leads downward. The catheter is 3-4 centimeters under the collarbone to the right of the parasternal line. Constant monitoring of the electrocardiogram indices is necessary, since too deep catheter insertion can disrupt the heart rhythm. This will help the pediatric kit for catheterization of the central veins.
• Aspiration test. After the catheter is inserted, the syringe is withdrawn in order to understand whether arterial or venous blood comes from the puncture site. If in doubt, then blood is taken for analysis. If aspiration occurs freely, then the installed catheter can be used for infusion therapy. It is necessary to check the correctness of the installed catheter using x-rays and only then fix it.
• Monitoring the condition of the patient. Immediately after installation of the catheter, the patient requires intensive monitoring to timely identify the complications that may become pneumothorax.
• CVK. Each installed catheter should be marked in a special schedule indicating the date, place of installation and type of catheter. In case of emergency insertion of a catheter without observing aseptic conditions, it should be removed as soon as possible and sent for analysis. The Seldinger central vein catheterization kit is the most popular.
  

Catheter Care

It is necessary to avoid disconnecting the system and manipulating it. The excesses and unsanitary condition of the catheter are unacceptable. The system is fixed so that there are no displacements in the puncture area. The development of complications and the risk of their occurrence should be checked daily. The best option is to apply a transparent bandage to the catheter insertion site. The catheter is subject to urgent removal in the event of a systemic or local infection during catheterization of the central vein.

Hygiene Standards

In order to avoid urgent removal of the catheter, strict adherence to hygienic standards and asepsis when installing it is necessary. If the CVC was installed at the scene of the accident, then it is removed after the patient is taken to the hospital. It is necessary to exclude any unnecessary manipulations with the catheter and follow the rules of asepsis when taking blood and injections. Disconnecting the catheter from the infusion system requires disinfection of the CVC nozzle with a special solution. It is necessary to use sterile dressings and single-use plugs for a three-way valve, minimize the number of tees and joints, and strictly monitor the parameters of protein, white blood cells and fibrinogen in the blood to avoid infection.

Following all these rules, you can not change the catheter often. After removing the CVC, the syringe is sent for a special study, even if there are no symptoms of infection.

Replacement

The length of stay of the needle for catheterization of the central veins is not regulated, it depends on the patient's susceptibility to infections and the body's response to the introduction of CVC. If the catheter is inserted into the peripheral vein, replacement is necessary every 2-3 days. When inserted into the central vein, the catheter is removed at the first symptoms of sepsis or fever. A syringe removed under sterile conditions is sent for microbiological examination. If the need to replace the CVC arises in the first 48 hours, and at the puncture point there is no irritation or signs of infection, a new catheter is placed according to the Seldinger method. Following all the requirements of asepsis, the catheter is pulled back a few centimeters so that it remains with the syringe in the vessel, and only then the syringe is removed. After the gloves are replaced, a conductor is inserted into the lumen and the catheter is removed. Then a new catheter is inserted and fixed.

Possible complications

Following the procedure, the following complications are possible:

• Pneumothorex.
• Hematoma, hemomediastinum, hemothorax.
• Arterial puncture with a risk of damage to the integrity of blood vessels. Hematomas and bleeding, false aneurysms, strokes, arteriovenous fistulas and Horner's syndrome.
• Pulmonary embolism.
• Puncture of lymph vessels with chylomediastinum and chylothorax.
• Incorrect catheter position in vein. Infusothorax, a catheter in the pleural cavity or too deep in the ventricle, or atrium on the right side, or the wrong direction of CCV.
• Damage to the brachial or cervical plexus, phrenic or vagus nerves, stellate ganglion.
• Sepsis and catheter infection.
• Vein thrombosis.
• Heart rhythm disturbance during catheter advancement for catheterization of central veins according to Seldinger.

CVC installation

There are three main areas for installing a central venous catheter:

• Subclavian vein.
• Jugular internal vein.
• Femoral vein.
  

A qualified specialist must be able to place a catheter in at least two of these veins. When catheterizing the central veins, ultrasound monitoring is especially important. This will contribute to the localization of the vein and the determination of the structures associated with it. Therefore, it is important to be able to use the ultrasound machine when possible.

The sterility of the central vein catheterization kit is of paramount importance, as it is necessary to minimize the risk of infection. The skin must be treated with special antiseptics, the injection site should be covered with sterile wipes. Sterile gowns and gloves are strictly required.

The patient's head goes down, which allows to fill the central veins, increasing their volume. This situation facilitates the catheterization process, minimizes the risk of pulmonary embolism during the procedure itself.

The internal jugular vein is most often used to install a central venous catheter. With this type of access, the risk of pneumothorax is reduced (compared with subclavian catheterization). In addition, in case of bleeding, it is stopped by squeezing a vein by compression hemostasis. However, this type of catheter is inconvenient for the patient; it can displace the wires of the temporary pacemaker.

Protocol Actions

The central vein catheterization protocol involves the following actions:

• The most optimal is to use a needle for catheterization according to Seldinger (introduction through a conductor). Peripheral catheters are more difficult to install.
• Before administration, it is necessary to anesthetize the skin and fiber with lidocaine (1-2% solution).
• The needle is put on a syringe with a solution of sodium chloride.
• The conductor is located in a sterile place for easy access.
• An incision is made on the skin with a small scalpel. This is done to facilitate the cannula insertion process.
• Further, it is necessary to advance the needle by pulling the piston to maintain negative pressure.
• If it was not possible to get into the vein, you need to slowly pull up the needle while continuing to maintain negative pressure in the syringe. There are cases of puncture through the vein. In this case, pulling up the needle helps.
• If the attempt to insert a catheter is unsuccessful, the needle is flushed to remove particles that block the lumen. Next, the location of the veins is once again evaluated and a new tactic for catheter insertion is determined.
• As soon as the needle enters the vein and the blood enters the syringe, you need to slightly push the needle back or forward so that the blood can flow quietly.
• With one hand supporting the needle, remove the syringe.
• A flexible wire conductor is then introduced. It passes into the needle pavilion with the lowest possible resistance. You can make this procedure a little easier by changing the angle of the bevel.
  
• If the resistance when moving the conductor is strong enough, it is necessary to check the position of the needle by aspirating blood.
• As soon as a large half of the conductor is inserted into the vein, the needle must be removed and a catheter with dilator put on the conductor.
• The introducer sheath cannot be moved forward until a small section of the conductor begins to protrude beyond the distal end of the expander and is firmly fixed.
• If resistance to the introduction of CVC occurs, the incision can be increased. If resistance occurs in the deeper layers, you can first introduce a small diameter expander to open the passage.
• After the catheter is fully inserted, the expander is removed, and the CVC is fixed with a transparent bandage and ligature.
• In conclusion, an X-ray examination is performed to monitor the position of the catheter. If installed without complications, the catheter can be used immediately without additional control.

Access to the subclavian vein

Insertion of a catheter into the subclavian vein is used when there is no access to the patient’s neck. This is possible with cardiac arrest. The catheter installed in this place is located on the front of the chest, it is convenient to work with it, it does not cause inconvenience to the patient. The disadvantages of this type of access is a high risk of developing pneumothorax and the inability to squeeze the vessel if it is damaged. If it was not possible to install a catheter on one side, you should not immediately try to insert it on the other, as this dramatically increases the risk of pneumothorax.

The installation of a catheter involves the following steps:

• There is a point on top of the rounded edge of the clavicle between one third of the medial and two thirds of the lateral.
• The injection site is located 2 centimeters below this point.
• Next, anesthesia is administered, and both the puncture site and the area of ​​the clavicle around the initial point are anesthetized.
• A catheterization needle is inserted in the same manner as anesthesia.
• As soon as the end of the needle is under the collarbone, you need to deploy it to the lower point of the jugular notch of the sternum.

Access through the femoral artery is especially often used in emergency cases, as it helps to enter the large vein for further manipulations. In addition, with this type of access, it is easy to stop bleeding by squeezing a vein. This access allows you to put a temporary pacemaker. The main complication of this type of catheterization is a high risk of infection and the required immobility of the patient.

How is a catheter inserted?

A catheter is inserted as follows:

• The patient is in a horizontal position. The leg turns around and retracts to the side.
• The inguinal region is shaved, the skin is treated with an antiseptic and covered with sterile wipes.
• The femoral artery is palpated in the area of ​​the fold at the base of the leg.
• The anesthesia of the catheter insertion area is performed.
• The needle is inserted at an angle of 30-45 degrees.
• Vienna is usually located at a depth of about 4 cm.

Central vein catheterization is a complex and dangerous medical manipulation. It should be carried out only by an experienced and qualified specialist, since a mistake in this case can cost the patient life and health.

What is included in the dual-channel central vein catheterization kit?

The sterile (disposable) installation kits include a port chamber, a port catheter, a thin-walled needle, a 10 cm ³ syringe, two locking locks, a conductor with a soft J-shaped tip in the unwinder, two Huber needles without a catheter, a vein lift, one Huber needle with fixing wings and attached catheter, bougie-dilator, tunnel, cleavable introducer sheath.

Central vein catheterization kit

The kit is designed for catheterization of the superior vena cava according to the Seldinger method. Long-term administration of drugs, parenteral nutrition, and invasive monitoring of blood pressure may be required.

A known set for catheterization of central veins "Certofix".

In the kit you can see:

• Polyurethane radiopaque catheter with extension cords equipped with a clip.
• Igloo Seldinger (introducer).
• Conductor direct kapron.
• Dilator (expander).
• Additional mount for fixing to the patient’s skin.
• Plug with injection membrane.
• Mobile clip.

Set for central venous catheterization "Certofix" is used most often.