State of the art: total parenteral nutrition: a guide for its use.

A brief review of TPN might more clearly point out and explain some of the major areas of this protocol. The use of subclavian vein catheterization for hyperosmolar solutions is the key to TPN. The tip of the catheter resides in the superior vena cava, so solutions with a concentration of 1,500-2,200 mOsm/l. (over five times the osmolarity of serum) can be infused at a rate of 2-3 ml./min. while being diluted by a blood flow of 2-5 l./min. (a dilution factor of a thousand). The site of the catheter is in a large vein. The cutaneous entry site of the catheter is in the pectoral skin below the clavicle; site must be kept scrupulously clean and dressed sterilely. Because of potential complications, the patient should be carefully observed and monitored.