title: Observation Versus Embolization in Patients with Blunt Splenic Injury After Trauma: A Propensity Score Analysis.
abstract: BACKGROUND
  Non-operative management (NOM) is the standard of care in hemodynamically stable patients with blunt splenic injury after trauma. Splenic artery embolization (SAE) is reported to increase observation success rate. Studies demonstrating improved splenic salvage rates with SAE primarily compared SAE with historical controls. The aim of this study was to investigate whether SAE improves success rate compared to observation alone in contemporaneous patients with blunt splenic injury.
  
  
  METHODS
  We included adult patients with blunt splenic injury admitted to five Level 1 Trauma Centers between January 2009 and December 2012 and selected for NOM. Successful treatment was defined as splenic salvage and no splenic re-intervention. We calculated propensity scores, expressing the probability of undergoing SAE, using multivariable logistic regression and created five strata based on the quintiles of the propensity score distribution. A weighted relative risk (RR) was calculated across strata to express the chances of success with SAE.
  
  
  RESULTS
  Two hundred and six patients were included in the study. Treatment was successful in 180 patients: 134/146 (92 %) patients treated with observation and 48/57 (84 %) patients treated with SAE. The weighted RR for success with SAE was 1.17 (0.94-1.45); for complications, the weighted RR was 0.71 (0.41-1.22). The mean number of transfused blood products was 4.4 (SD 9.9) in the observation group versus 9.1 (SD 17.2) in the SAE group.
  
  
  CONCLUSIONS
  After correction for confounders with propensity score stratification technique, there was no significant difference between embolization and observation alone with regard to successful treatment in patients with blunt splenic injury after trauma.
authors.affiliation: Trauma Unit Department of Surgery, Academic Medical Center, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
authors.forename: Dominique C
authors.initials: DC
authors.lastname: Olthof
authors.affiliation: Surgical Department, Medisch Centrum Alkmaar, Alkmaar, The Netherlands.
authors.forename: Pieter
authors.initials: P
authors.lastname: Joosse
authors.affiliation: Clinical Research Unit, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Patrick M M
authors.initials: PM
authors.lastname: Bossuyt
authors.affiliation: Trauma Research Unit Department of Surgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: Philippe P
authors.initials: PP
authors.lastname: de Rooij
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Loek P H
authors.initials: LP
authors.lastname: Leenen
authors.affiliation: Department of Surgery, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Klaus W
authors.initials: KW
authors.lastname: Wendt
authors.affiliation: Department of Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Frank W
authors.initials: FW
authors.lastname: Bloemers
authors.affiliation: Trauma Unit Department of Surgery, Academic Medical Center, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands. j.c.goslings@amc.nl.
authors.forename: J Carel
authors.initials: JC
authors.lastname: Goslings
mesh_terms: D000007:Abdominal Injuries / Q000175:diagnosis / Q000628:therapy*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D057216:Propensity Score; D012189:Retrospective Studies; D013154:Spleen / Q000293:injuries*; D013157:Splenic Artery; D016896:Treatment Outcome; D014949:Wounds, Nonpenetrating / Q000175:diagnosis / Q000628:therapy*; D055815:Young Adult