title: Circulating complement proteins in multiple trauma patients--correlation with injury severity, development of sepsis, and outcome.
abstract: OBJECTIVE
  To investigate protein complement 3a (C3a) and protein complement 3 (C3) plasma levels in trauma patients directly after the injury, in relation to the patients' outcome, the development of sepsis, or the injury severity, as determined by either the Polytrauma Score (PTS), the Injury Severity Score (ISS), or the Trauma and Injury Severity Score (TRISS).
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Surgical intensive care unit in a university hospital.
  
  
  METHODS
  Thirty-four patients with multiple trauma.
  
  
  METHODS
  None.
  
  
  RESULTS
  C3a and C3 concentrations, as well as the C3a/C3 ratio, were determined at the time of the accident (T0), at the emergency admission (T1), 8 hrs after the accident (T2), and every 8 hrs until day 3, every 12 hrs until day 6, and once daily on days 7 and 8. The C3a plasma concentrations and the C3a/C3 ratios of nonsurvivors were significantly greater at T0 or T1 as compared with those survivors (p = .008 or .033). Patients who developed sepsis had higher C3a plasma levels at the scene of accident than patients without complications. However, these differences did not reach statistical significance (p = .051), although a clear trend was apparent. Patients were grouped according to the severity of injury, as determined by either the PTS, ISS, or TRISS. We found significant differences in the both the mean C3a values and the C3a/C3 ratio among the different groups, during the first 8 hrs after the injury. In addition, a significant correlation was observed between the C3a concentration or the C3a/C3 ratio at T0 to T2 and either the ISS (r2 = .49), PTS (r2 = .22) or the TRISS (r2 = .45), which was similar to correlations between injury severity scores themselves (r2 = .36 to .58).
  
  
  CONCLUSIONS
  Complement activation occurs immediately after the injury. The degree of activation is a hallmark for the outcome of a patient. Determination of C3a concentrations, at the scene of the accident, may prove helpful to assess the severity of the injury and to determine the prognosis. The amount of C3a and the C3a/C3 ratio may be useful as additional parameters to the existing trauma scoring systems, such as, PTS, ISS, and TRISS.
authors.affiliation: Institute of Medical Microbiology, Hannover Medical School, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Hecke
authors.forename: U
authors.initials: U
authors.lastname: Schmidt
authors.forename: A
authors.initials: A
authors.lastname: Kola
authors.forename: W
authors.initials: W
authors.lastname: Bautsch
authors.forename: A
authors.initials: A
authors.lastname: Klos
authors.forename: J
authors.initials: J
authors.lastname: Köhl
mesh_terms: D000063:Accidents, Traffic; D000328:Adult; D003176:Complement C3 / Q000302:isolation & purification*; D015926:Complement C3a / Q000302:isolation & purification*; D004630:Emergencies; D006801:Humans; D015601:Injury Severity Score; D009104:Multiple Trauma / Q000097:blood* / Q000145:classification / Q000150:complications / Q000401:mortality; D011446:Prospective Studies; D012128:Respiratory Distress Syndrome / Q000097:blood / Q000401:mortality; D018805:Sepsis / Q000209:etiology / Q000401:mortality
chemical_list: D003176:Complement C3; D015926:Complement C3a