[Standard parenteral nutrition preparations and caloric adjustment]

In parenteral nutrition it is necessary to adjust the intake to the estimated caloric requirements. These needs may be achieved by the use of bi- or tricameral nutrition (EPN), although they present some rigidity regarding their composition.

To assess the adequacy of caloric intake using EPN, to determine the factors conditioning it and the associated complications.

Cohort, prospective, and observational study for 9 months in surgical patients. The calculated needs were compared with actual intake. The factors conditioning the excess and deficit (weight, age, stress factor, height, glycemia, and triglyceridemia) were studied by means of a multivariant method. The metabolic complications associated to the excess or deficit (hyperglycemias, hypertriglyceridemias) were studied by using the Student's t test. The theoretical calculations with the Harris-Benedict and the Mifflin equations were compared by lineal correlation regression.

94 patients were studied. In 87% of them, the caloric intake was within the +/- 15% range of the theoretical mean. Thirty patients had caloric excess, whereas 61 had deficit. Patients with high weight (> 68 kg), stress factor > 1.2, and hypertriglyceridemias (> 3 mmol/L) had higher risk for caloric deficit. Twenty two point eight percent had hyperglycemias that were correlated with caloric excess. Nineteen point eight percent had hypertriglyceridemias associated to caloric deficit. When comparing both formulas, the values correlated well except for those patients with low weight and advanced age.

Although EPN fits the caloric requirements in most of the patients, in those with high weight, hypercatabolism, and hypertriglyceridemia there is a risk for caloric deficit.