[Modular parenteral nutrition: a new concept?]

We may define Modular Parenteral Nutrition (MPN) as parenteral nutrition (PN) mixtures obtained from adding different macronutrients to standard formulations (SPN) both binary (amino acids and glucose) and ternary (amino acids, lipids, and glucose).

The aim of this study is to demonstrate that PN formulations may be adapted to individual needs of each patient and workload may be reduced by using MPN.

Case-control retrospective study of PN prepared during the first semester of the years 1995, 2000, and 2005. PN are categorized in: standard (SPN) -given without manipulation-, individualized (IPN), and modular parenteral nutrition (MPN). The protocols are compared at the different periods, and the volume of transferred fluid is related with total prepared volume in order to calculate the workload. The Chi squared and student's t tests with a significance level of p < 0.05 are used.

In 1995, virtually only individualized formulations were used. In the year 2000, SPN and MPN were introduced as maintenance formulas as well as those for moderate stress. Finally, in the year 2005, the modular concept has been introduced for severe stress and/or immunomodulatory formulas. As a result of these changes, we observe in the protocol a decrease in IPN due to progressive introduction of MPN. In 1995, MPN represented 2.6% of all elaborations, increasing up to 64.7% in 2000, and to 74.7% in 2005. This fact has resulted in a decrease in transferred volume through the volumetric elaboration system. In 1995, 87.3% of the total volume was transferred, in the year 2000 34.3%, and finally in 2005 only 20.6% (the differences between the three periods are statistically significant; p < 0.05). In the year 2005, 543 IPN were elaborated, of which 169 (31.1%) were for patients with liver encephalopathy or non-dialyzed acute renal failure. The following ingredients have been added to MPN during that same period: glutamine, fish oil lipid emulsions lipidicas, structured lipids, olive-pattern lipids, polyionic solutions, and specific micronutrients.

MPN allows for adapting PN formulas to a wide range of clinical situations, although individualized formulations still are irreplaceable for some pathologies. The use of MPN is associated with a decrease in individualized formulas that reflects in lower workload.