Definition and Overview
A central line placement, also known as a central venous catheterization or central venous access, is the placing of a catheter into a large vein. This is done for several possible reasons, such as administering fluids and medications, measuring the pressure in a central vein, or performing a special type of blood test called the central venous oxygen saturation, among others. The catheter is inserted through a sensitive procedure that uses special methods such as the Seldinger technique to ensure the accuracy of placement and prevent the possible complications of the procedure, which include infection, bleeding, and pneumothorax, among others.
Who Should Undergo and Expected Results
The three main uses of a central venous catheter are to administer medication, monitor venous pressure, and collect blood for lab tests.
For the administration of medication, this method is used only for certain drugs, such as:
- Long-term antibiotics
- Long-term pain medications
- Chemotherapy drugs
- Drugs that may cause phlebitis when placed in the peripheral veins (these include calcium chloride, hypertonic saline, potassium chloride, and vasopressors such as dopamine and epinephrine.)
- Continuous rehydration (administration of fluids)
For blood collection, a central line becomes necessary when:
- Blood draws are frequently necessary due to the patient’s condition
- Collecting peripheral blood stem cell
- Peripheral venous access is not possible
- A dialysis is necessary
The procedure is most beneficial for patients who are chronically ill, are hospitalized for an extended period of time, and require repeated or continuous intravenous access for the delivery of fluids, drugs, or nutrition. This is because a central venous catheter may be left in place for a longer period compared to other intravenous options.
How Does the Procedure Work?
A central venous catheter may be placed into the:
- Internal jugular vein in the neck
- Subclavian vein in the chest
- Axillary vein in the chest
- Femoral vein in the groin
Different types of lines may also be placed depending on the intended purpose; these include:
- PICC (peripherally inserted central catheter) line
- Groshong tunneled catheter
- Quinton non-tunneled catheter
The procedure to place a central line into a vein begins with the cleaning of the area where the catheter will be inserted, followed by the application of a local anesthetic. The cleaning of the skin, which is done using povidone-iodine or chlorhexidine, plays a key role in the prevention of infection.
After this, the doctor proceeds to identify the specific venous location, which is most commonly done using an ultrasound device, and inserts the hollow needle that will allow line placement. Sometimes, doctors also aspirate a bit of blood to check its flow rate and the color of the blood, both of which will help confirm whether the blood is indeed from a central line or an artery. Once confirmed that the position is correct, the line may be inserted and the hollow needle removed.
Regardless of purpose, location, or type, the placement requires a sterile technique to prevent the line from becoming the cause of infection or a port of entry for organisms. One common technique is called the Seldinger technique, which used a guidewire through which the central line can be passed. The process can be guided by ultrasound to reduce the risk of complications, and is typically followed by an x-ray to ensure that the line is correctly placed and that no complications occurred.
Possible Risks and Complications
The procedure to insert a central line is a sensitive one, with a high risk of possible complications due to incorrect or unsterile placement. Thus, doctors usually weigh the benefits against the risks to ensure that central venous catheterization is a good option for the patient.
The following are some of the complications associated with central line placement.
Infection - The risk of infection is one that is commonly present in all catheterization procedures because the catheters can easily allow bacteria to enter the bloodstream. Central venous catheters are specifically linked with bloodstream infections caused by the Staphylococcus aureus and Staphylococcus epidermidis bacteria. Thus, certain standards, such as hand hygiene, full-body drapes, and antiseptic use, are now in place and are further being improved to reduce this risk. In case of an infection, the patient will be treated with antibiotics, but the catheter would also have to be removed, especially when confirmed that it is the cause of the infection. This can be verified by taking a blood culture from the catheter and another vein and comparing the growth rate of bacteria taken from both lines.
Pneumothorax - Pneumothorax is a complication that may occur following a central line placement in the chest, especially with subclavian vein catheterizations. Fortunately, using ultrasonography during the procedure can minimize the risk.
Misplacement - There is a small risk that the line will be placed incorrectly. This risk is higher with neck placements wherein the line may be inserted into the vertebral artery or the carotid artery. In some cases, the line may be correctly placed, but its tip might be misdirected, for example, into the subclavian vein rather than the superior vena cava.
Thrombosis - There is a small risk of the patient developing a venous thrombosis or a deep vein thrombosis in the upper extremity.
Air embolism - There is a risk of causing blood vessel obstruction when air gets sucked into the vein during the insertion and eventually form air bubbles.
Bleeding complications - Bleeding complications such as hematoma or hemorrhage may also occur. These tend to be more common in neck placements.
Arrhythmia - There is a risk that the line may push against the endocardium during the insertion. This is, however, easily resolved during the procedure by pulling the line back and reinserting it.
In general, proper insertion techniques and the use of ultrasound guidance can minimize or even prevent the risks and complications.
- Shapey IM, Foster MA, Whitehouse T, et al. Central venous cather-related bloodstream infections: improving post-insertion catheter care. J Hosp Infect. 2009;71:117-122.