Response to total parenteral nutrition in the extremely malnourished patient

Changes in serum albumin levels and body weight are often used as indicators of the efficiency of a nutritional support regimen. Patients with moderate nutritional depletion demonstrate two distinct patterns of response during refeeding. The first is characterized by a decrease in the previously expanded extracellular fluid space with a rise in serum albumin and a loss of weight and the second by continued fluid retention with weight gain and no rise in serum albumin concentration. The second pattern has been observed in patients with ongoing stress such as infection. This study examines severely malnourished patiets with no apparent inflammatory complications and demonstrates that this group responds to nutritional support in a pattern similar to that seen in the stressed patient. Eight patients with profound malnutrition were studied during the 1st week of nutritional support. Nitrogen balance was measured and the findings confirmed that all patients were anabolic. Sodium balances were used as an indicator of changes in the extracellular fluid compartment. Body weight and serum albumin were assessed daily. Body weight increased from 59 ± 4 to 62 ± 4% of normal (p < 0.01) while serum albumin changed insignificantly (3.00 ± 0.27 to 2.85 ± 0.23 g/100 ml, NS) during the initial week of an adequate nutritional support regimen (nitrogen balance was +21.0 ± 4.3 g, p < 0.05). These changes were associated with a positive sodium balance (+215 ± 20 mEq, p < 0.05). These data confirm that some extremely malnourished patients do not experience a diuresis during the initial phase of nutritional support but rather may retain water and increase body weight. This study also emphasizes that a failure of albumin to rise is not a reflection of poor nitrogen balance but rather a reflection of sodium retention.