title: Perioperative haemorrhage in endovascular abdominal aneurysm repair affects outcome.
abstract: OBJECTIVE
  This study aimed to evaluate the outcome and predisposing factors related to perioperative bleeding in patients treated with endovascular aneurysm repair (EVAR) for ruptured and non-ruptured abdominal aortic aneurysm (AAA).
  
  
  METHODS
  This was a retrospective cohort study.
  
  
  METHODS
  A total of 525 consecutive patients (73% elective) with AAA underwent EVAR at two vascular centres from 2008 to 2011. From registry data perioperative bleeding was analysed in relation to outcome and preoperative data.
  
  
  RESULTS
  A total of 453 (86%) patients presented with a perioperative bleeding <1000 ml, 42 (8%) patients 1000-1999 ml, 19 (4%) patients 2000-5000 ml and 11 (2%) >5000 ml. Other than ruptured AAA (n = 90), no preoperative risk factors for increased perioperative bleeding were found. Open femoral artery access (n = 101), branched (n = 18) and uni-iliacal endografts (n = 18) and introducer size were associated with increased perioperative bleeding (P < 0.001). In multivariable logistic regression only rupture and perioperative bleeding >2000 ml were significantly related to 30-day mortality (odds ratio 10.6 (range 3.8-29.6) and 13.4 (range 4.8-37.4), respectively). Postoperative renal failure, multi-organ failure, >5 days at intensive care unit, bowel ischaemia and abdominal compartments syndrome were significantly related to perioperative bleeding >2000 ml (P < 0.001).
  
  
  CONCLUSIONS
  Large perioperative bleeding during EVAR is a clinical problem that affects outcome. About 10% of elective AAA patients and 34% of patients with ruptured AAA, undergoing EVAR, present a perioperative blood loss exceeding 1 l. In our study, a perioperative blood loss exceeding 2 l was independently associated with increased mortality and morbidity in both acute and elective AAA patients. Open femoral access, branched EVAR and larger diameter introducers were associated with increased perioperative blood loss. ETHICAL APPLICATION: 2011/664-31/3 (approved).
authors.affiliation: Center of Molecular Medicine and Surgery, Department of Vascular Surgery, Karolinska Institute, Karolinska University Hospital, Stockholm SE-171 76, Sweden. carl.montan@karolinska.se
authors.forename: C
authors.initials: C
authors.lastname: Montán
authors.forename: M
authors.initials: M
authors.lastname: Wannberg
authors.forename: J
authors.initials: J
authors.lastname: Holst
authors.forename: C M
authors.initials: CM
authors.lastname: Wahlgren
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D016063:Blood Loss, Surgical / Q000706:statistics & numerical data*; D015984:Causality; D015331:Cohort Studies; D057510:Endovascular Procedures; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019106:Postoperative Hemorrhage / Q000453:epidemiology*; D012189:Retrospective Studies; D016896:Treatment Outcome