What is an Intravenous Catheter or IV cannula?
An Intravenous Catheter(IV cannula or peripheral venous catheter) is a catheter (small, flexible tube) placed into a peripheral vein(usually in a Patient’s arm or leg) in order to administer medication or fluids. Upon insertion, the line can be used to draw blood.
A tourniquet is applied to a Patient’s arm or leg so that the return blood flow of the veins is reduced and the veins are easier to see. The skin is cleaned with an antiseptic agent, the doctor is wearing sterile gloves and the catheter is then introduced into the vein by a needle (similar to blood drawing), which is subsequently removed while the small tube of the cannula remains in place. The catheter is then fixed by taping it to the Patient’s skin (unless there is allergy to adhesives). Newer catheters have been equipped with additional safety features to avoid needle stick injuries. Modern catheters consist of synthetic polymers such as teflon (hence the often used term ‘Venflon’ or ‘Cathlon’ for these venous catheters).
A peripheral venous catheter is the most commonly used vascular access in medicine. It is given to most emergency room and surgical patients, and before some radiological imaging techniques using radiocontrast, for example. In the United States, more than 25 million patients get a peripheral venous line each year.
A peripheral venous catheter is usually placed in a vein on the hand or arm. It should be distinguished from a central venous catheter(Central Venous Lines) which is inserted in a central vein (usually in the internal jugular vein of the neck or the subclavian vein of the chest), or an Arterial Catheter which can be placed in a peripheral as well as a central artery. In children, a local anaesthetic gel (such as lidocaine) is applied to the insertion site to facilitate placement.
Why is it done?
In Intensive Care, he purpose of IV cannulation is to give your loved one fluids and/or medication. Directly administering fluids and medications into the vein, means that your loved one will receive the effects of the treatment much more quickly than by any other route. Your loved one may also need a cannula in case of an emergency.
Does it hurt?
The only pain endured is generally at insertion point of the needle for a brief period.
- The sterile dressing should be kept clean and dry and therefore must be covered when showering or bathing
- The cannula should be changed every three days and most hospitals have a policy regarding how often the cannula should be changed
What are the risks?
Infection, phlebitis(inflammation of a vein), extravasation(leaking fluids into the tissues) leading to infiltration, air embolism(air bubbles), hemorrhage (bleeding) and formation of a hematoma (bruise) may occur.
Because of the risk of insertion-site infection recommendations are that the catheter needs to be replaced every 72 hours.
If you have any more questions about catheterisation, you can ask one of the many doctors and nurses looking after your friend or relative.
All Intensive Care interventions and procedures carry a degree of potential risk even when performed by skilled and experienced staff. Please discuss these issues with the medical and nursing staff who are caring for your loved one.
The information contained on this page is general in nature and therefore cannot reflect individual Patient variation. It is meant as a back up to specific information which will be discussed with you by the Doctors and Nurses caring for your loved one. INTENSIVE CARE HOTLINE attests to the accuracy of the information contained here BUT takes no responsibility for how it may apply to an individual Patient. Please refer to the full disclaimer.