Evolution of energy expenditure and nitrogen excretion in severe head-injured patients

Autor: N. Bruder, G. Francois, J. C. Dumont
Rok vydání: 1991
Předmět:
Zdroj: Critical Care Medicine. 19:43-48
ISSN: 0090-3493
DOI: 10.1097/00003246-199101000-00013
Popis: OBJECTIVE The aim of the study was to estimate the influence of therapeutic changes on the level of energy expenditure (EE) and N excretion in a homogeneous group of patients usually considered hypermetabolic. DESIGN EE and N excretion of head-injured patients were measured simultaneously at phases 1 and 2 (patients treated 4 +/- 3 and 18 +/- 8 days after injury, respectively). SETTING Acute care hospital. PATIENTS Eight severe head-injured patients, mean weight 63.1 +/- 6.1 (SD) kg, mean age 21 +/- 3.8 (SD) yr. INTERVENTIONS At phase 1, all patients were sedated with fentanyl (6.7 +/- 1.9 micrograms/kg.hr) plus flunitrazepam (9.1 +/- 4.8 micrograms/kg.hr) and were mechanically ventilated. All patients received continuous total parenteral nutrition. The nonprotein caloric intake averaged 1092 +/- 200 kcal/day, including 77% glucose and 23% fat (Intralipid 20%). The total N intake averaged 7 +/- 5 g/day, consisting of crystalline amino acids. At phase 2, no patient received any sedative and all were breathing spontaneously via tracheostomy. All patients received parenteral and/or enteral nutrition. The nonprotein caloric intake averaged 1929 +/- 200 kcal/day consisting of 65% carbohydrates and 35% fat. The total N intake averaged 13 +/- 2 g/day. MEASUREMENTS AND MAIN RESULTS The EE was significantly higher at phase 2 than at phase 1 (2121 vs. 1737 kcal), but the interindividual variability was low at both phases. N excretion was high at the two periods of the study and not correlated to the level of EE. The RQ was 0.75 at both periods, indicating predominant fat oxidation. CONCLUSIONS We could not demonstrate any parallelism in the evolution of EE and protein catabolism in head-injured patients. The therapeutics (mechanical ventilation, sedation, and nutrition) have a major effect on EE but little on N excretion.
Databáze: OpenAIRE