title: Clinical endpoint, early detection, and differential diagnosis of postoperative ileus: a systematic review of the literature.
abstract: BACKGROUND
  This systematic review summarizes evidence regarding clinical endpoints, early detection, and differential diagnosis of postoperative ileus (POI).
  
  
  METHODS
  Using MEDLINE, EMBASE, Cochrane, and Web-of-Science, we identified 2,084 articles. Risk of bias and level of evidence (LOE) of the included articles were determined, and relevant results were summarized.
  
  
  RESULTS
  Eleven articles were included, most of which with substantial risks of bias. Bowel motility studies revealed that defecation together with solid food tolerance is the most representative clinical endpoint of POI (LOE: 2b); other clinical signs (e.g. bowel sounds, passage of flatus) did not correlate with a full recovery of bowel motility. Inflammatory parameters including interleukin (IL)-6, IL-1, and TNF-α might assist in an early detection of prolonged POI (LOE: 4). Clinical manifestations (e.g. nausea, vomiting, abdominal distension, bowel sounds, flatus) and X-ray examinations provided limited aid to the differential diagnosis of POI, while CT with Gastrografin had the best specificity and sensitivity (both 100%; LOE: 1c).
  
  
  CONCLUSIONS
  Postoperative defecation together with tolerance of solid food intake seems to be the best clinical endpoint of POI. CT has the best differential diagnostic value between POI and other complications. Prospective studies with a high LOE are in great need.
authors.affiliation: Department of Surgery, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Zhouqiao
authors.initials: Z
authors.lastname: Wu
authors.forename: Geesien S A
authors.initials: GS
authors.lastname: Boersema
authors.forename: Adem
authors.initials: A
authors.lastname: Dereci
authors.forename: Anand G
authors.initials: AG
authors.lastname: Menon
authors.forename: Johannes
authors.initials: J
authors.lastname: Jeekel
authors.forename: Johan F
authors.initials: JF
authors.lastname: Lange
mesh_terms: D003937:Diagnosis, Differential; D042241:Early Diagnosis; D006801:Humans; D045823:Ileus / Q000175:diagnosis*; D011183:Postoperative Complications / Q000175:diagnosis*