A double lumen catheter is a long, flexible medical device that consists of one hollow tube within another hollow tube. The word “lumen” means an open area inside an object, as in the lumen of the intestine. It differs from a single lumen catheter in that it enables two different actions to take place close together and with less tissue trauma. These actions could be the withdrawal of fluid or the insertion of fluid, air or small medical devices. These catheters can be used to drain blood, urine or unwanted liquid, such as from the lungs or abscesses.
A double lumen catheter can be made from one of many flexible materials, such as silicone, latex, Teflon® or polyurethane. The catheter might have a needle associated with it that can be removed after the catheter is in place and access points — called hubs or injection ports — on the ends of the lumens that remain outside the body. Often, the two lumens in the catheter open in different places. Sometimes, they will open on opposite sides of the body of the tube, and other times, one will open at the tip of the tube and the other will open a short distance away from the tip. A hemodialysis catheter might meet both of those conditions at the same time.
Foley catheters are double lumen catheters used for cases where the urinary bladder can’t be emptied by normal means because of health issues that the patient has. One lumen allows saline to fill a small balloon at the lumen’s tip, inside the bladder, to hold the catheter in place. The other lumen carries urine out of the bladder. Urinary catheter use carries a high risk of catheter infection, so catheters with antibiotic agents either coating the surface or infused in the flexible material are often used in the urinary tract.
In angioplasty, a double lumen catheter can be used so that a guide wire and a fiber-optic cable can be introduced simultaneously to allow close observation of the angioplasty catheter. The angioplasty catheter itself might also have two lumens. One of these lumens can inject air into the balloon near the tip, and the other can inject dyes, medication or extra blood.
In the case of a tracheotomy, a double lumen catheter can be used to ventilate the patient and suction out any fluid buildup concurrently and through the same opening. Central venus catheters with double lumens allow the blood pressure in the central circulatory system to be monitored as well as allowing medications and nutrition to be introduced very close to the heart. In a patient who regularly receives dialysis treatment and has excessive scarring on the veins, an ateriovenous fistula — a connection between an artery and a vein — is often formed surgically to enlarge the vein and make needle insertion easier. A double lumen catheter is used while the newly formed fistula is maturing so that blood can be removed, cleaned and then returned to the body.