The development of parenteral nutrition and the current status of nutritional education in the USA Stanley J.Dudrick, M.D., F.A.C.S. Dept. of Surgery Bridgeport Hospital, Bridgeport, CT, USA From a practical point of view, the history of the development of parenteral nutrition began almost four centuries ago with the discovery of the circulation of blood by William Harvey. Since that time, countless experiments and experiences in animals, human beings and in basic science laboratories have led to the accumulation of a broad base of data and knowledge which has been refined, adapted and applied for the purpose of achieving complete nutritional support entirely by vein. Progress toward this goal was made slowly during the 17th, 18th and 19th centuries, but increased significantly during the early and mid 20th century, and has accelerated geometrically during the past five decades with the rapid advancement of technology. The prevailing dogma in the 1960's was that feeding entirely by vein was impossible; even if it were possible, it would be impractical; and even if it were practical, it would be unaffordable. The principles fundamental to the success of Total Parenteral Nutrition (TPN) were to: 1.) calculate the calories, amino acids and micronutrients required for achievement of positive nitrogen balance, weight gain, tissue repair and/or growth and development, 2.) concentrate the essential nutrient substrates in the volume of water that the patient or subject can tolerate and metabolize safely and efficaciously, 3.) infuse the resultant nutrient formulation continuously at the rate of optimal tissue utilization, preferably by pump, into a large central vein, such as the superior vena cava wherein the high blood flow can instantly dilute the hypertonic infusate to near isotonicity, 4.) maintain aseptic and antiseptic conditions during all phases of preparation, modification, and infusion of the formulation and throughout the achievement an long-term maintenance of venous access, handling and managing all components of the infusion and administration apparatus, and in all other aspects of the care of the surgical patient in order to minimize the ever present threat of infection and sepsis. The components essential to successful TPN included optimal intravenous nutrient substrates, sterilization and sterility throughout the process, durable inert central venous catheters, dependable safe infusion pumps, and strict adherence to the principles of safe central venous access and long-term central venous catheterization. After first applying these prerequisites to the intravenous feeding of beagle puppies and achieving normal growth and development thereby for the first time ever, the technique was subsequently applied successfully to critically ill surgical patients long-term with the regular achievement of positive nitrogen balance, weight gain, increased activity, and accelerated recovery, convalescence and rehabilitation. The dramatic demonstration of normal growth and development in a newborn infant fed entirely by vein for almost two years validated the clinical usefulness of TPN and changed the practice of medicine forever. TPN has spawned a professional, scientific, technological and industrial revolution in nutritional support, clinical biochemistry, physiology and biology. It has also demonstrated the essentiality for fundamental, integrated and continuing nutritional education in the professional school curriculum, postgraduate training programs and for life-long learning thereafter. Several aspects of the current status of nutritional education in the USA will be presented and discussed. From "The 8th Congress of the PENSA Program & Abstract" Kochi, Japan, November 5-7, 2002 Page : 21