title: The role of total cell-free DNA in predicting outcomes among trauma patients in the intensive care unit: a systematic review.
abstract: BACKGROUND
  Cell-free DNA has been proposed as a means of predicting complications among severely injured patients. The purpose of this systematic review was to assess whether cell-free DNA was useful as a prognostic biomarker for outcomes in trauma patients in the intensive care unit.
  
  
  METHODS
  We searched Pubmed, Embase, Scopus and the Cochrane Central Register for Controlled Trials and reference lists of relevant articles for studies that assessed the prognostic value of cell-free DNA detection in trauma patients in the intensive care unit. Outcomes of interest included survival, posttraumatic complications and severity of trauma. Due to considerable heterogeneity between the included studies, a checklist was formed to assess quality of cell-free DNA measurement.
  
  
  RESULTS
  A total of 14 observational studies, including 904 patients, were eligible for analysis. Ten studies were designed as prospective cohort studies; three studies included selected patients from a cohort while one study was of a retrospective design. We found a significant correlation between higher values of cell-free DNA and higher mortality. This significant correlation was evident as early as on intensive care unit admission. Likewise, cell-free DNA predicted the severity of trauma and posttraumatic complications in a majority of patients.
  
  
  CONCLUSIONS
  The amount of cell-free DNA can function as a prognostic tool for mortality and to a lesser extent severity of trauma and posttraumatic complications. Standardizing cell-free DNA measurement is paramount to ensure further research in cell-free DNA as a prognostic tool.
authors.affiliation: Center for Surgical Science, Department of Gastrointestinal Surgery, Zealand University Hospital, Lykkebækvej 1, 4600, Køge, Denmark. mgog@regionsjaelland.dk.
authors.forename: Mikail
authors.initials: M
authors.lastname: Gögenur
authors.affiliation: Center for Surgical Science, Department of Gastrointestinal Surgery, Zealand University Hospital, Lykkebækvej 1, 4600, Køge, Denmark.
authors.forename: Jakob
authors.initials: J
authors.lastname: Burcharth
authors.affiliation: Center for Surgical Science, Department of Gastrointestinal Surgery, Zealand University Hospital, Lykkebækvej 1, 4600, Køge, Denmark.
authors.forename: Ismail
authors.initials: I
authors.lastname: Gögenur
mesh_terms: D000073888:Cell-Free Nucleic Acids / Q000235:genetics* / Q000502:physiology; D005820:Genetic Testing / Q000379:methods*; D006760:Hospitalization; D006801:Humans; D007362:Intensive Care Units / Q000458:organization & administration; D011446:Prospective Studies; D012189:Retrospective Studies; D014947:Wounds and Injuries / Q000235:genetics*
chemical_list: D000073888:Cell-Free Nucleic Acids
keywords: Intensive care unit; Trauma; cfDNA; mtDNA; nDNA