In the world of medicine, vascular access is a means of accessing the circulatory system through peripheral or central vascular systems to obtain blood or administer drugs. The vascular access procedure involves inserting a sterile plastic tube called a catheter into a blood vessel. Type of catheter can be either peripheral or centrally located. The peripheral catheter is approximately one inch long and inserted into a small vein in the forearm. The central catheter is larger and longer and inserted into the large vein of the extremities, neck, or chest. Central venous catheter is the main modality used for the delivery of chemotherapeutic agents. The duration of central venous catheterization depends on the type of treatment given.
Video Vascular access for chemotherapy
Central venous catheter
The central venous catheter (CVC) is a catheter inserted into the large vein of the arm, neck, chest, or groin. CVC is used for the delivery of drugs, nutrients, or blood products for a longer time, usually weeks to months. There are several reasons for the use of central venous access:
- To get more than one drug at a time
- To get continuous infusion chemotherapy (more than 24 hours or more)
- To get nutrition
- To get routine maintenance
- To get home care
- To get long-term therapy (for months or even longer)
- To get drugs that can cause serious damage to the skin and muscle tissue if they leak outside the blood vessels (this drug is known as vesicant). Carrying them through CVC rather than short-term IV reduces the risk that drugs will leak and damage tissues.
The types of CVC include peripherally installed central catheters, tunnel catheters, and planted ports.
Centrally mounted central catheter
Central central mounted catheter (PICC, pronounced "pick"), is a form of vascular access that is inserted in peripheral sites such as arm veins and extends in the central venous system of the superior vena cava. The catheter is inserted into a blood vessel in the arm like a cephalic, basilic, or brachial vein and then progresses to the heart. This line can then be used for the delivery of chemotherapy agents. PICC deletion is a relatively simple procedure that can be done by trained nurses even in outpatient settings. This area is bandaged and allowed to recover.
Connected catheter
The tunnel catheter is a catheter (thin tube) placed in the vein for long-term use. It is most often placed in the neck (internal jugular) but can also be placed in the crotch (femoral), liver (transhepatic), chest (subclavian) or back (translumbar). The catheter is inserted into the vessels under an ultrasound or fluoroscopic guide and channeled through the skin. The tunnel catheter has several channels called lumens that lie on the surface of the skin. This lumens is the access point when the catheter is used. Tunable catheters can be single, double, or triple lumened. Removal of a tunnel catheter is a simple procedure that requires only local anesthesia. Bandages are applied to the site to heal.
Embedded port
Ports are similar to tunnel catheters but are left completely under the skin. Medicines are injected through the skin into the catheter. Some of the planted ports contain small, rechargeable reservoirs in the same way. Once filled, the reservoir slowly releases the drug into the bloodstream. The embedded port is less obvious than the tunnel catheter and requires little daily maintenance. It has less impact on one's activity than the PICC line or tunnel catheter. The surgically implanted infusion port is placed under the clavicle (fossa infraklavicular), with a thoracic catheter to the heart (right atrium) through a large vein. Once embedded, the port is accessed through a non-penetrating "Huber" needle inserted through the skin. The doctor may need to use topical anesthesia before accessing the port. Ports can be used for medicine, chemotherapy, and blood. Because the port is located completely underneath the skin, the port is easier to maintain and has a lower risk of infection than a CVC or PICC catheter. Ports are usually used in patients who only require occasional venous access during long-term therapy. Because the port should be accessed using a needle, if venous access is required frequently, catheters with external access are more commonly used.
Maps Vascular access for chemotherapy
Central venous catheter complications
Complications associated with central venous catheters include infection, pneumothorax, thrombosis, misplacement, and bleeding.
Pneumothorax
Penumothorax may occur during catheter insertion. Use of ultrasound guidance guidance in reducing penumothorax risk by ensuring proper placement through direct visualization.
Infection
Catheters can enter bacteria into the bloodstream that can cause local infection and possibly sepsis. The risk of infection is reduced during insertion through the use of sterile techniques and appropriate catheter care after insertion which includes keeping the catheter area clean, washing hands before use, and applying clean dressings. In the case of central duct infection, the tract is removed and the appropriate antimicrobial agent is administered according to the type of organism and the severity of the infection from the clinical condition.
Bleeding
Because a catheter is placed inside a blood vessel there is always a risk of bleeding during placement and when the catheter is in place. Bleeding can range from local hematoma (bruises) to bleeding (many bleeding).
Thrombosis
The use of central venous catheters is a risk factor for the formation of blood clots in the upper extremities. Aetiology is thought to be due to the activation of clotting cascades by trauma to the blood vessels during placement as well as the presence of foreign objects in the blood vessels. For patients with central venous access, wide variations in the incidence of venous thrombosis (1 to 66 percent) are reported and the incidence depends on the type of catheter and location, the criteria for the diagnosis, and the population under study.
Incorrect placements
The CVC placement error is more common when the person's anatomy is different or difficult because of an injury or past surgery. CVC may be erroneously placed in the artery during insertion (eg, carotid artery or vertebral artery when placed in the neck or common femoral artery when placed in the groin). During the central placement of the subclavian vein, the catheter may be inadvertently pushed into the internal jugular vein on the same side rather than the superior vena cava. Chest x-rays are performed after insertion to rule out this possibility. The tip of the catheter can also be misguided to the contralateral (opposite) side of the subclavian in the neck, rather than to the superior vena cava. The risk of misplacement is reduced through the use of ultrasound or fluoroscopic guidance that allows direct visualization of the catheter during placement. The post-x-ray procedure is also obtained to confirm the exact position.
References
Source of the article : Wikipedia
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