The quality of nutrition at an intensive care unit

Adequate nutrition of patients remaining at an intensive care unit (ICU) is of great importance since both over- and undernutrition can lead to serious morbiditv and even mortality. The aim of our study was to examine whether patients at an ICU are adequately fed. A prospective follow-up was performed in 39 surgical and medical mechanically ventilated patients who were at least two days on the ICU prior to inclusion. The mean age of the patients was 65 years (range 23 to 88) and 40% was female. For each patient the following data were collected. First, the exact amounts of macronutrients (carbohydrates, fat and proteins) given over 24 hours by parenteral and/or enteral route were calculated ('administered'). Second, on the same day indirect calorimetric measurement (Deltatrec(TM) II metabolic monitor) was performed over 18 hours and urinary nitrogen loss was measured over 24 hours in order to estimate energy expenditure and macronutrient usage ('measured'). Third, by means of formulas developed by Harris Benedict and Long we calculated the needs for energy and macronutrients based on the clinical information obtained on the day prior to the day the indirect calorimetric measurements were performed ('calculated'). In 10 patients (26%) the administered amount of energy was lower than the measured amount. In 16 patients (41%) the protein balance was negative. Four of the patients (10%) received more than 1500 kcal above the measured amount. In 11 patients (28%) the calculated amount of energy was lower than the measured energy expenditure. Coefficients of correlation between measured versus administered, calculated versus administered and measured versus calculated amounts of energy were 0.19 (p = 0.25), 0.03 (p = 0.87) and 0.57 (p 0.0002), respectively. In conclusion, a substantial part of patients at an intensive care unit are not adequately fed. Some improvement of the quality of feeding can be established by using the Harris-Benedict formula in the prescribing of nutrition; measurement of the caloric and protein needs is the preferred method to adequately feed ICU patients. (C) 2002 Elsevier Science Inc. All rights reserved.