title: Thromboembolic events in bariatric surgery: a large multi-institutional referral center experience.
abstract: BACKGROUND
  The risk of venous thromboembolic (VTE) events is increased in patients undergoing bariatric surgery. Population studies examining VTE rates after bariatric surgery often lack details and uniformity regarding the prophylactic regimens used. The aim of this study was to determine the incidence of VTE in patients undergoing laparoscopic bariatric surgery.
  
  
  METHODS
  Database searches from Cleveland Clinic bariatric surgery programs in Cleveland, OH, and Weston, FL, were conducted from January 2005 to January 2013. Mechanical and chemical prophylaxes were provided for all patients as per protocol. Data on age, gender, body mass index (BMI), interval between procedure and VTE, inpatient versus outpatient status, anticoagulation prophylaxis, type of surgery and mortality were collected.
  
  
  RESULTS
  A total of 4,293 patients underwent primary or revisional bariatric surgery during this 8-year time period. VTE events were identified in 57 patients (1.3 %). Pulmonary embolism (PE) was identified in 39 patients (0.9 %), and 15 of these patients had negative duplex studies of the lower extremities. Deep venous thrombosis only was identified in 18 patients (0.4 %). VTE rates for gastric bypass (n = 2,945), sleeve gastrectomy (n = 709), gastric banding (n = 467) and revisional procedures (n = 171) were 1.1, 2.9, 0.2 and 6.4 %, respectively. Eight patients had VTE diagnosed during their inpatient stay. The mean time to VTE diagnosis after surgery was 24 days. Seventeen patients who developed VTE had been prescribed extended prophylaxis for 2-4 weeks after discharge. There was only one VTE-related mortality from PE reported in this cohort (0.02 %). Univariate and multivariate analyses revealed age, BMI, open and revisional surgery as predictive of VTE (p < 0.05).
  
  
  CONCLUSIONS
  The risk of VTE among morbidly obese patients undergoing bariatric surgery is persistent despite use of laparoscopy and aggressive prophylactic anticoagulation policy. Patients with advanced age, higher BMI and those undergoing open or revisional surgery are at higher risk of postoperative VTE.
authors.affiliation: Bariatric and Metabolic Institute, Cleveland Clinic, Cleveland, OH, USA, mjamal110@gmail.com.
authors.forename: Mohammad H
authors.initials: MH
authors.lastname: Jamal
authors.forename: Ricard
authors.initials: R
authors.lastname: Corcelles
authors.forename: Hideharu
authors.initials: H
authors.lastname: Shimizu
authors.forename: Mathew
authors.initials: M
authors.lastname: Kroh
authors.forename: Fernando M
authors.initials: FM
authors.lastname: Safdie
authors.forename: Raul
authors.initials: R
authors.lastname: Rosenthal
authors.forename: Stacy A
authors.initials: SA
authors.lastname: Brethauer
authors.forename: Philip R
authors.initials: PR
authors.lastname: Schauer
mesh_terms: D000328:Adult; D000368:Aged; D050110:Bariatric Surgery / Q000379:methods; D005260:Female; D006801:Humans; D015994:Incidence; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D009767:Obesity, Morbid / Q000601:surgery; D011183:Postoperative Complications / Q000453:epidemiology; D012017:Referral and Consultation; D012086:Reoperation; D012189:Retrospective Studies; D018570:Risk Assessment; D054556:Venous Thromboembolism / Q000453:epidemiology* / Q000517:prevention & control