[Quality of artificial nutritional support in an intensive care unit]

To assess what are the reasons for discrepancies between the amount of nutrients delivered, prescribed and theoretical requirements, in an intensive care unit.

Prospective cohort study over a 5 months period.

Intensive Care Unit of the Insular University Hospital in Gran Canaria.

Adult patients who were prescribed enteral and or parenteral nutrition for > or = 2 days and we followed them for the first 14 days of nutrition delivery.

The prescribed and the delivered calories were calculated every day, whereas the theoretical requeriments were calculated after the ICU stay, by using the Harris-Benedict formula adjusted with a stress factor. Also the reason for cessation of enteral tube feeding > 1 hour in the days of artificial nutrition were analyzed.

Fifty-nine consecutive patients, receiving nutritional support either enterally or intravenously, and 465 nutrition days analyzed. Nutrition was initiated within 48 hours after ICU admission. Enteral nutrition was the preferential route used. Seventy-nine percent of the mean caloric amount required was prescribed, and 66% was effectively delivered; also 88% of the amount prescribed was delivered. The low ratio of delivered-prescribed calories concerned principally enteral nutrition and was caused by gastrointestinal intolerance. We observe a wide variation in practice patterns among physicians to start, increase, reduce or stop enteral nutrition when symptoms of intolerance appear.

In our ICU exists an important difference between the caloric theoretical requests and the quantity really delivered; this deficit is more clear in the enteral nutrition. The knowledge of this situation allows to take measures directed to optimizing the nutritional support of our patients. Possibly the motivation in the medical and nursery personnel in carrying out nutritional protocols it might be the most effective measurement, which it would be necessary to confirm in later studies.