Hunger and appetitive factors during total parenteral nutrition

A previous study of short-term (average of 31 days) Total Parenteral Nutrition (TPN) patients indicated that they experienced hunger even though they received adequate calories for energy balance. A prolonged suppression of hunger was noted when lipid was added to the total nutrient intake. Recent experiments with intravenous infusion of lipids in normal volunteers have failed to show appetite suppression beyond that expected from caloric regulation. The goal of our study was to collect information regarding hunger and appetitive experiences associated with intravenous alimentation of healthy, long-term, home TPN patients. Our results from questionnaire returns of 29 respondents showed hunger to be generally low during most of the day. Those patients taking small amounts of food orally typically reported moderate hunger before eating. There was no evidence of any significant difference between hunger reports given on days when lipid was infused vs. days when lipid was omitted. Aversive sensations were frequently associated with lipid infusion but not with nonlipid nutrient infusion. Hunger in TPN patients is discussed in terms of expectancy and hedonic factors as contrasted with physiological need.