A central line also known as central venous catheter (CVC), is a catheter placed into a large vein. Catheters can be placed in veins in the neck (internal jugular vein), chest (subclavian vein or axillary vein), groin (femoral vein), or through veins in the arms (also known as a PICC line, or peripherally inserted central catheters).
When compared to a typical IV line, a central line is larger, can stay in place longer, can deliver a greater volume of fluids and allows blood to be drawn easily. A central line can also be used to measure fluid volume status, and to help determine if a patient is dehydrated or has received an adequate amount of fluid to support bodily functions.
In order to insert a central line, the patient must be lying flat, and the area of the body where the central line will be inserted is exposed. The patient is covered, typically from head to toe, with a sterile drape. The drape is a sterile paper sheet with a hole in it to allow the individual placing the central line access to the vein. The sterile drape is intended to help reduce the risk of infection, and studies have shown that covering the entire body, rather than just the area where the central line will be placed, is the best practice for the prevention of infection.
Once the patient is draped, the area of skin is cleaned. If the patient is awake, the area of skin may also be numbed with a local anesthetic. Using sterile technique, a hollow catheter is then inserted into the vein, typically using ultrasound to locate the appropriate blood vessel. The catheter is then stitched in place, or an adhesive device is used to hold the catheter still at the insertion site.
The area is then cleaned again with antiseptic and a sterile dressing is placed over the insertion site, with the lumens accessible. Placement of the catheter must be confirmed using an x-ray before the central line can be used, to avoid accidentally infusing medications into tissue or the wrong blood vessel. In some cases, the catheter may be in the correct vessel, but need slight adjustment because the catheter is either too far in the vessel or not quite far enough.
REFERENCES
https://www.verywellhealth.com/central-lines-why-is-a-central-line-necessary-3156818
https://www.webmd.com/heart-disease/what-are-central-venous-catheter
https://www.medicalopedia.org/161/central-line-placement-a-step-by-step-procedure-guide/