title: Erythropoietin measurements in severely traumatized patients.
abstract: BACKGROUND
  Despite numerous studies in critically ill patients, physiological adaptation to acute anaemia and the pattern of erythropoietin (EPO) secretion has not been well described in severely injured patients. The aim of this study was to describe EPO secretion and its relationship with haemoglobin (Hb) levels in severely injured patients.
  
  
  METHODS
  We performed an observational, prospective clinical study in our intensive care unit (ICU). For all patients with severe trauma (Injury Severity Score>15), EPO measurement was obtained on admission, during the first 3 days and then when Hb level was measured. Maximal EPO level (EPOmax) and minimal Hb level (Hbmin) during the ICU stay was determined for all patients.
  
  
  RESULTS
  One hundred and seventy-one consecutives patients were included (440 EPO measurements). Seventy-nine patients (46.2%) showed an increased value (> or =25 UI/l) EPOmax value. Most EPOmax values were observed early after the trauma [within 4 days for 63 patients (82.8%)]. Plotting EPOmax to Hbmin values show that a threshold Hbmin value of 105 g/l best discriminated patients with and without an elevated EPO secretion. Less than 10% of the patients with Hbmin<105 g/l did not increase their EPO secretion.
  
  
  CONCLUSIONS
  In severely traumatized patients a marked response to acute anaemia is observed in most patients. In our study, Hb threshold for a significant EPO secretion following post-traumatic acute anaemia was 105 g/l. The peak level was achieved early in the course of the anaemia.
authors.affiliation: Department of Anaesthesia, Traumatology and Intensive Care, North University Hospital, Marseilles, France. renaud.vialet@ap-hm.fr
authors.forename: R
authors.initials: R
authors.lastname: Vialet
authors.forename: C
authors.initials: C
authors.lastname: Ventré
authors.forename: M
authors.initials: M
authors.lastname: Leone
authors.forename: C
authors.initials: C
authors.lastname: Conforto
authors.forename: C
authors.initials: C
authors.lastname: Martin
mesh_terms: D000328:Adult; D000740:Anemia / Q000378:metabolism*; D004921:Erythropoietin / Q000097:blood / Q000378:metabolism*; D005260:Female; D006454:Hemoglobins / Q000032:analysis*; D017052:Hospital Mortality; D006801:Humans; D015601:Injury Severity Score; D007902:Length of Stay; D008297:Male; D011446:Prospective Studies; D012016:Reference Values; D013997:Time Factors; D014947:Wounds and Injuries / Q000145:classification / Q000378:metabolism*
chemical_list: D006454:Hemoglobins; D004921:Erythropoietin