Brief history of parenteral and enteral nutrition in the hospital in the USA.

The meteoric rise in parenteral and enteral nutrition was largely a consequence of the development of total parenteral nutrition and chemically defined diets in the late 1960s and early 1970s and the recognition of the extensive prevalence of protein calorie malnutrition associated with disease in this same period. The establishment of Nutrition Support Services (NSS) using the novel, multidisciplinary model of physician, clinical nurse specialist, pharmacist, and dietitian, which, at its peak in the 1990s, approached 550 well-established services in about 10% of the US acute care hospitals, also fostered growth. The American Society of Parenteral and Enteral Nutrition, a multidisciplinary society reflecting the interaction of these specialties, was established in 1976 and grew from less than 1,000 members to nearly 8,000 by 1990. Several developments in the 1990s initially slowed and then stopped this growth. A system of payments, called diagnosis-related groups, put extreme cost constraints on hospital finances which often limited financial support for NSS teams, particularly the physician and nurse specialist members. Furthermore, as the concern for the nutritional status of patients spread to other specialties, critical care physicians, trauma surgeons, gastroenterologists, endocrinologists, and nephrologists often took responsibility for nutrition support in their area of expertise with a dwindling of the model of an internist or general surgeon with special skills in nutrition support playing the key MD role across the specialties. Nutrition support of the hospitalized patient has dramatically improved in the US over the past 35 years, but the loss of major benefits possible and unacceptable risks of invasive nutritional support if not delivered when appropriate, delivered without monitoring by nutrition experts, or employed where inappropriate or ineffective will require continued attention by medical authorities, hospitals, funding agencies, and industry in the future.