[Iron-deficiency anemia in enteral nutrition: correlation with tube position]

Enteral alimentation is a commonly employed procedure for pre-operative rehabilitation and nutritional maintenance of depleted patients suffering from esophageal diseases. In a prospective study of 61 cases exhibiting benign (n = 38) and malignant (n = 23) conditions, a commercial polymeric diet was supplied in the proportion of 40 Kcal/kg/day during at least two weeks. The liquid preparation was infused by bolus technique at home, by the patients themselves, via nasogastric (n = 25) or nasoduodenal silastic tube (n = 36). Total food intake, that before treatment had been under 60% of estimated requirements, reached the expected range throughout the therapeutic period, and also iron input was adequate (0.3 mg/kg/day). Standart anthropometric and biochemical assessment of these cases, with included serum iron and hemoglobin concentration, indicated stabilization of general nutritional parameters, but with persistence of moderate anemia(hemoglobin 12.6 +/- 2.0 g/dl; iron 59.2 +/- 35.7 mg/dl). Stratification of the population according to enteral tube position demonstrated similar diagnoses and clinical conditions for both groups. Mean initial iron and hemoglobin concentration was also the same, but final serum iron was increased after gastric administration (p < 0.05) and diminished with duodenal diet (p < 0.05). It is concluded that: home enteral nutrition in malnourished patients with esophageal diseases is consistent with an acceptable nutritional status, but without significant recovery from anemia, serum iron in this population only increases after intra-gastric alimentation; it is probable that this last finding is related to impaired ionization and absorption of dietary iron, when food is introduced in a postpyloric site.