title: Anastomotic leak after colorectal resection: A population-based study of risk factors and hospital variation.
abstract: Anastomotic leak is a major source of morbidity in colorectal operations and has become an area of interest in performance metrics. It is unclear whether anastomotic leak is associated primarily with surgeons' technical performance or explained better by patient characteristics and institutional factors. We sought to establish if anastomotic leak could serve as a valid quality metric in colorectal operations by evaluating provider variation after adjusting for patient factors.
  
  
  
  We performed a retrospective cohort study of colorectal resection patients in the Michigan Surgical Quality Collaborative. Clinically relevant patient and operative factors were tested for association with anastomotic leak. Hierarchical logistic regression was used to derive risk-adjusted rates of anastomotic leak.
  
  
  
  Of 9,192 colorectal resections, 244 (2.7%) had a documented anastomotic leak. The incidence of anastomotic leak was 3.0% for patients with pelvic anastomoses and 2.5% for those with intra-abdominal anastomoses. Multivariable analysis showed that a greater operative duration, male sex, body mass index >30 kg/m2, tobacco use, chronic immunosuppressive medications, thrombocytosis (platelet count >400 × 109/L), and urgent/emergency operations were independently associated with anastomotic leak (C-statistic = 0.75). After accounting for patient and procedural risk factors, 5 hospitals had a significantly greater incidence of postoperative anastomotic leak.
  
  
  
  This population-based study shows that risk factors for anastomotic leak include male sex, obesity, tobacco use, immunosuppression, thrombocytosis, greater operative duration, and urgent/emergency operation; models including these factors predict most of the variation in anastomotic leak rates. This study suggests that anastomotic leak can serve as a valid metric that can identify opportunities for quality improvement.
authors.affiliation: Department of Surgery, University of Michigan Health System, Ann Arbor, MI. Electronic address: vnikolia@med.umich.edu.
authors.forename: Vahagn C
authors.initials: VC
authors.lastname: Nikolian
authors.affiliation: Department of Obstetrics and Gynecology, University of Michigan Medical School, Ann Arbor, MI.
authors.forename: Neil S
authors.initials: NS
authors.lastname: Kamdar
authors.affiliation: Department of Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Scott E
authors.initials: SE
authors.lastname: Regenbogen
authors.affiliation: Department of Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Arden M
authors.initials: AM
authors.lastname: Morris
authors.affiliation: Department of Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: John C
authors.initials: JC
authors.lastname: Byrn
authors.affiliation: Department of Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Pasithorn A
authors.initials: PA
authors.lastname: Suwanabol
authors.affiliation: Department of Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Darrell A
authors.initials: DA
authors.lastname: Campbell
authors.affiliation: Department of Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Samantha
authors.initials: S
authors.lastname: Hendren
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D057868:Anastomotic Leak / Q000453:epidemiology* / Q000503:physiopathology / Q000601:surgery*; D015992:Body Mass Index; D002423:Cause of Death; D015331:Cohort Studies; D003082:Colectomy / Q000009:adverse effects* / Q000379:methods; D015179:Colorectal Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D018572:Disease-Free Survival; D005260:Female; D061847:Hospitals, High-Volume / Q000639:trends; D061846:Hospitals, Low-Volume / Q000639:trends; D006801:Humans; D016015:Logistic Models; D008297:Male; D008824:Michigan; D008875:Middle Aged; D015999:Multivariate Analysis; D061646:Operative Time; D017063:Outcome Assessment, Health Care; D011159:Population Surveillance; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D016019:Survival Analysis