title: [Nitrogen losses and nitrogen balance in patients with malignant infarction of the median cerebral artery submitted to moderate hypothermia (32-33 degrees C)].
abstract: OBJECTIVE
  Induction of moderate hypothermia in patients with median cerebral artery (MCA) infarction may produce metabolic and nutritional impairments. Currently, we do not know which is the best method to carry out nutritional assessment in this population group. The aim of the present study was to assess the usefulness of nitrogen balance in the follow-up of patients with MCA submitted to moderate hypothermia (32-33 degrees C) by means of intravascular cooling at the Neurocritical Patients Unit at a tertiary hospital.
  
  
  METHODS
  We designed a retrospective study including patients with MCA infarction of whom we gathered bio-demographical, clinical, hypothermia, and nutritional variables. Similarly, we carried out a prospective follow-up of a patient with MCA infarction and induced hypothermia, gathering the same variables at different time points of his clinical course.
  
  
  RESULTS
  Six patients with MCA infarction submitted to moderate hypothermia for a mean duration of 12 days (interval 9-15) were included in the retrospective series. We observed that nitrogen losses (mean 9.9 g) were lower than those previously thought for critical patients during the acute phase. During the prospective follow-up of the patient with malignant infarction of the MCA from day 1 to day 22 after the application of hypothermia, low levels of nitrogen losses were similarly observed during the phase of induced hypothermia, which increased later on when the patient recovered normothermia. The mean nitrogen expenditure during the period of hypothermia was 10.7 g and increased up to 27.3 g during the normothermia period (day 17).
  
  
  CONCLUSIONS
  These results suggest that moderate hypothermia-induced metabolic suppression is clinically relevant and thus the determination of nitrogen balance does not seem to be a useful tool in the nutritional followup of this type of patients.
authors.affiliation: Servicio de Farmacia, Hospital Universitario Vall d'Hebrón, Area de Traumatología, Barcelona, España. plalueza@vhebron.net
authors.forename: M P
authors.initials: MP
authors.lastname: Lalueza Broto
authors.forename: M
authors.initials: M
authors.lastname: Duero Adrados
authors.forename: A
authors.initials: A
authors.lastname: Robles González
authors.forename: M
authors.initials: M
authors.lastname: Riveiro Vilaboa
authors.forename: A
authors.initials: A
authors.lastname: Garnacho de Vega
authors.forename: J
authors.initials: J
authors.lastname: Sahuquillo Barris
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009584:Nitrogen / Q000378:metabolism*; D012189:Retrospective Studies
chemical_list: D009584:Nitrogen