Catheters are tubes that can be inserted into the body to allow for either the drainage or administration of fluids to and from the body. One that is divided into two parts is called a split catheter. This specific type of catheter is normally used in the process of hemodialysis, facilitating the exchange of blood for those who must undergo frequent cleaning of the blood due to kidney failure. The split catheter is surgically implanted in patients to minimize the need to repeatedly puncture veins for dialysis treatments.
During hemodialysis, most commonly referred to as dialysis, it is necessary to remove the blood from the body, mechanically filter it, and return it to the body. This is performed on an ongoing basis. During this process, blood flows out of the body, through the dialysis machine where it is cleaned, and filters back into the body in one continuous loop.
In order to filter properly, blood must be removed from the patient through one tube and sent to the machine, then returned to the patient through another tube. For patients without a catheter, this means that two needles must be inserted into his or her veins every time dialysis is performed, usually three times per week. One needle is used to remove the blood from the patient and send it to the dialysis machine, and the other needle provides an access point for the return of the cleaned blood to the patient.
In many cases, a split catheter is surgically implanted in the hemodialysis patient to allow access to the circulatory system without the need to place needles in the veins every single time the patient receives treatment. A catheter is typically preferred for patients who are receiving relatively short term dialysis or who have problems that prevent the use of other access methods. A surgeon places the split catheter in the patient's body, usually connecting it to the jugular vein to provide the best rate of flow through the tubing when it is accessed. The rest of the catheter is tunneled underneath the skin, and the access ports are brought out through the person’s chest several inches from where it enters the jugular. This distance helps to provide a barrier to infection, though infection is still a common problem with any kind of catheter use.
Once the catheter is in place, it can be used to provide easy access to the patient’s circulatory system. The split catheter has two tubes, or lumens, on it, both of which enter the jugular vein under the skin. It also has two separate access points where it exits the body. One of these is connected to the input side of the dialysis machine and the other is connected to the output side. This allows all of the blood to flow out one half of the split catheter, through the dialysis machine, and back into the body through the other half of the catheter to complete the circuit.
