Total parenteral nutrition (TPN) is administering all nutrition intravenously. TPN can cause thrombosis (blood clot) in the smaller peripheral veins because it is so concentrated. A central venous catheter, or intravenous (IV) port, is usually placed in one of the larger veins (closer to the heart) of your body to keep this from happening. Any intravenous device can be hooked up to the port. TPN should only be used when absolutely necessary. It is better to use the GI tract whenever possible. However, sometimes it is not possible to use the GI tract or you may have to rest your bowels. Some conditions that necessitate TPN are bowel obstructions, Crohn's disease, ulcerative colitis, short bowel syndrome (from surgery), prolonged diarrhea or congenital GI issues. TPN is made up of carbohydrates, proteins and fats in a balanced ratio. Dextrose makes up about 25 percent and 20 percent to 30 percent of the TPN is lipids (fats). This can change depending on the person receiving the TPN. Electrolytes are added in quantities that are specific for each recipient. The content of the solution will vary depending on the condition being treated as well. For instance, someone with kidney issues will receive a solution with less protein than someone whose kidneys are functioning properly. TPN should have its own dedicated line going into the central venous catheter. Strict aseptic technique should always be practiced when connecting the TPN line to the catheter.If you are receiving TPN at home, you will need to learn how to use aseptic technique and to recognize a line that has become infected. Lab tests should be done to monitor if the TPN is supplying all the necessary nutrients and how your body is using them. Weight, CBC (complete blood count), electrolytes, BUN (blood urea nitrogen), blood glucose, fluid intake and output, liver function tests and plasma proteins are some of the tests that need to be done to accomplish this.