An intravenous (IV) catheter is a hollow tube that a doctor or nurse can thread through a vein to provide a route to administer medications and fluids directly into the bloodstream. IV catheters are usually placed in the hand, arm, or leg. Sometimes they are run into one of the internal or external jugular veins in the neck, or in a vein under the collar bone or in the chest. Some catheters are permanent and remain under the skin, while others are visible coming out of the skin, and usually remain in place for a fixed period of time.
Patients undergoing treatment for cancer, AIDS, or other serious medical conditions may receive a permanent internal IV catheter. External catheters are often used on patients with serious but acute illnesses. They are also commonly used in surgery, for medication and anesthesia. Some drugs and nutrients can only be administered intravenously, so a catheter must be used.
To place an IV catheter, a doctor or nurse cleans the skin around the area where the tube will be placed, and punctures the skin with a needle to gain access to the vein. He or she will then thread the catheter into the vein and attach it to flexible tubing that usually runs to a bag filled with fluids or medication. The procedure of placing the catheter is usually relatively painless, and most patients do not feel pain or discomfort once the tube is in place.
These devices are safe for most patients, but healthcare professionals may have to seek alternative sites to place the tube if the skin around common placement areas is burned, injured, or infected. Most of the time, an IV catheter does not cause further problems, but it must be kept clean and sterile to prevent infection. Redness, pain, swelling, or warmth around the catheter are signs of possible infection and the tubing may be removed entirely or relocated to another area in patients who experience these symptoms.
The tubing can irritate the interior of the vein, causing it to trigger blood clots. These are typically small and harmless when the catheter is in the arm, hand, or leg, and this condition usually resolves on its own. Sometimes an IV catheter may pierce a vein entirely and cause internal bleeding, called a hematoma, which appears as a bruise or lump on the skin around the injection site. Most hematomas require no treatment and go away within a few days. Rarely, an IV needle may injure a nerve. Most of the time, nerves repair themselves within a few months, but occasionally surgery is necessary to correct the damage.