title: Intraoperative modifiable risk factors of colorectal anastomotic leakage: Why surgeons and anesthesiologists should act together.
abstract: BACKGROUND
  Colorectal anastomotic leakage (CAL) is a major surgical complication in intestinal surgery. Despite many optimizations in patient care, the incidence of CAL is stable (3-19%) [1]. Previous research mainly focused on determining patient and surgery related risk factors. Intraoperative non-surgery related risk factors for anastomotic healing also contribute to surgical outcome. This review offers an overview of potential modifiable risk factors that may play a role during the operation.
  
  
  METHODS
  Two independent literature searches were performed using EMBASE, Pubmed and Cochrane databases. Both clinical and experimental studies published in English from 1985 to August 2015 were included. The main outcome measure was the risk of anastomotic leakage and other postoperative complications during colorectal surgery. Determined risk factors of CAL were stated as strong evidence (level I and II high quality studies), and potential risk factors as either moderate evidence (experimental studies level III), or weak evidence (level IV or V studies).
  
  
  RESULTS
  The final analysis included 117 articles. Independent factors of CAL are diabetes mellitus, hyperglycemia and a high HbA1c, anemia, blood loss, blood transfusions, prolonged operating time, intraoperative events and contamination and a lack of antibiotics. Unequivocal are data on blood pressure, the use of inotropes/vasopressors, oxygen suppletion, type of analgesia and goal directed fluid therapy. No studies could be found identifying the impact of body core temperature or mean arterial pressure on CAL. Subjective factors such as the surgeons' own assessment of local perfusion and visibility of the operating field have not been the subject of relevant studies for occurrence in patients with CAL.
  
  
  CONCLUSIONS
  Both surgery related and non-surgery related risk factors that can be modified must be identified to improve colorectal care. Surgeons and anesthesiologists should cooperate on these items in their continuous effort to reduce the number of CAL. A registration study determining individual intraoperative risk factors of CAL is currently performed as a multicenter cohort study in the Netherlands.
authors.affiliation: Máxima Medical Center, Department of Surgery, Veldhoven, The Netherlands. Electronic address: stefan.van.rooijen@mmc.nl.
authors.forename: S J
authors.initials: SJ
authors.lastname: van Rooijen
authors.affiliation: VU Medical Center, Department of Surgery, Amsterdam, The Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: Huisman
authors.affiliation: Máxima Medical Center, Department of Surgery, Veldhoven, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Stuijvenberg
authors.affiliation: VU Medical Center, Department of Surgery, Amsterdam, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Stens
authors.affiliation: Máxima Medical Center, Department of Surgery, Veldhoven, The Netherlands.
authors.forename: R M H
authors.initials: RMH
authors.lastname: Roumen
authors.affiliation: VU Medical Center, Department of Surgery, Amsterdam, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Daams
authors.affiliation: Máxima Medical Center, Department of Surgery, Veldhoven, The Netherlands.
authors.forename: G D
authors.initials: GD
authors.lastname: Slooter
mesh_terms: D000714:Anastomosis, Surgical; D057868:Anastomotic Leak / Q000453:epidemiology*; D000740:Anemia / Q000453:epidemiology; D000767:Anesthesia, Epidural / Q000706:statistics & numerical data; D000072080:Anesthesiologists; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016063:Blood Loss, Surgical / Q000706:statistics & numerical data; D001794:Blood Pressure; D001803:Blood Transfusion / Q000706:statistics & numerical data; D001831:Body Temperature; D002316:Cardiotonic Agents / Q000627:therapeutic use; D003082:Colectomy; D003299:Cooperative Behavior; D013505:Digestive System Surgical Procedures; D006801:Humans; D006943:Hyperglycemia / Q000453:epidemiology; D007035:Hypothermia / Q000453:epidemiology; D015994:Incidence; D009426:Netherlands; D061646:Operative Time; D011183:Postoperative Complications / Q000453:epidemiology*; D012307:Risk Factors; D066231:Surgeons; D014662:Vasoconstrictor Agents / Q000627:therapeutic use; D014883:Water-Electrolyte Imbalance / Q000453:epidemiology; D014945:Wound Healing
chemical_list: D000900:Anti-Bacterial Agents; D002316:Cardiotonic Agents; D014662:Vasoconstrictor Agents
keywords: Anastomotic leakage; Anesthesiology; CAL; Colorectal; Intraoperative; Modifiable; Risk factor; Surgery