Malnutrition: a poorly understood surgical risk factor in aged cardiac patients.

This feasibility report is based on the fact that malnutrition has been recognized but too little understood in connection with surgical risk. Patients with cardiac cachexia are remarkably similar to many patients with cachexia of the aged. Cachectic patients generally go through an operation well, but their condition often deteriorates slowly and they die a few days later; they behave as if they are running out of energy reserves. Malnourished people can be divided into three categories: kwashiorkorlike, marasmic, and marasmic-kwashiorkorlike. Recognition and classification of protein/calorie malnutrition into these categories directs treatment. Recognition is based on the usual physical and laboratory tests, plus triceps skinfold/arm circumference observations; leukocyte counts, with absolute and relative lymphocyte counts; serial transferrin, globulin, and albumin assessments; and, particularly, Candida and mumps skin testing to identify the anergic state. Intravenous and oral hyperalimentation can bring about conspicuous improvement in the appearance, attitude, and ability to withstand stress--including major heart surgery--of malnourished patients. However, astute clinical balance is essential, since either oral or intravenous hyperalimentation may cause renal nitrogen overload; moreover, if intravenous delivery is too rapid, congestive heart failure may be precipitated.