Long-term parenteral nutrition

Nineteen patients (11 women and eight men) aged 20-68 received long-term parenteral nutrition, mostly at home, for six to 63 months (mean 19 months). Indications for LTPN were extensive, active Crohn''s disease in three patients, intestinocutaneous fistulas in three, and short-bowel syndrome in the remaining 13 patients. Subclavian or intra-atrial (Broviac) catheters were most commonly used, for which the average life was four and seven months respectively. Complications of long-term parenteral nutrition included pneumothorax in four out of 48 subclavian vein punctures. Catheter-induced thrombosis of central veins was shown by phlebography 17 times in nine patients, and eight episodes of total occlusion occurred. Two of these patients had pulmonary infarction. Nineteen episodes of catheter sepsis occurred in 11 patients, but only one was fatal. Complications related to intestinal disease included intra-abdominal abscesses and intestinal fistulas, and disturbances of liver function. Five patients died, though in only two was death related to long-term parenteral nutrition. One of these patients died from catheter sepsis, the other had subdural haematoma possibly caused by anticoagulant treatment. Eight of the 14 surviving patients still needed parenteral nutrition. All received a disability pension, but six had an acceptable quality of life with almost normal social activities.Despite problems such as difficulties in maintaining standardised infusion programmes, it was concluded that long-term parenteral nutrition at home is practicable and consistent with an acceptable quality of life.     

National nutrition surveillance

National Nutrition Surveillance includes nutritional assessment surveys to ascertain the extent of malnutrition in populations, to identify possible causes, to establish baseline data for monitoring nutrition, and to select mechanisms for nutrition surveillance (in a restricted sense). An example of the results from a recent nutritional assessment survey in the United States is the negative association of obesity with energy intake, exercise and socioeconomic status, which has implications for public nutritional policy. Nutritional monitoring measures changes in population nutrition over time. An example of the results from nutritional monitoring is the unexpected and presently unexplained decrease in serum cholesterol levels of middle-aged women in the United States over the past decade. Nutritional surveillance in the restricted sense not only identifies malnutrition but is administratively organized to intervene rapidly. National Nutrition Surveillance depends on metabolic and clinical research to decide on its priorities. This research indicates that malnutrition involves more than under-nutrition, and greater emphasis should be given in National Nutrition Surveillance to this wider context of malnutrition. These results will in turn help set priorities for basic and applied research in nutrition. It is important that the research community participate in the review presently under way of the role of the National Center for Health Statistics in National Nutrition Surveillance.     

Fats in nutrition

Investigation of the relationship of diet to blood lipids and atherosclerosis has dominated the field of lipid nutritional biochemistry for the past 25 years. Although this subject has consumed considerable time, effort, and research funds, it has also proved beneficial to other areas of lipid biochemistry by attracting qualified people to the field and by initiating development of sophisticated methodology and instrumentation required for progress in those areas. The development of capillary gas-liquid chromatography and high-performance liquid chromatography, together with more extensive computer control and processing of data, should accelerate progress in all areas of lipid biochemistry. In the next 25 years, I expect to see extensive investigation of dietary hydrogenated fats and their constituent isomeric fatty acids. Specificity of deposition in animal tissues, effects on blood lipids and coronary heart disease, and their relationship to polyunsaturated fatty acids and prostaglandins are among the topics likely to receive attention. The prostaglandins, prostacyclins, thromboxanes, and leukotrienes will continue to receive attention in the near future, and the role of diet in modulating the concentrations of these compounds in blood and other body tissues is a promising area of active research. The discovery of abnormalities in polyunsaturated fatty acid metabolism in pathological conditions in man has renewed interest in these dietary components. Association of neurological abnormalities with lack of linolenic acid metabolites should stimulate further investigation of the role of the n-3 series acids in central nervous system function.