• Gastrointestinal Motility
• Inflammatory Mechanisms
• Colorectal Surgery
• Mast Cells
• Macrophages

Postoperative ileus (POI) is the most common gastrointestinal (GI) motility disorder managed by surgeons in their clinical practice. The definition, pathophysiology, prevention, diagnosis and management of POI are still not determined. An expert consensus defined POI as a ‘transient cessation of coordinated bowel motility after surgical intervention, which prevents effective transit of intestinal contents and/or tolerance of oral intake’.1 Primary POI is a physiological response that occurs in almost all patients following abdominal surgery and is usually spontaneously resolved by the 5th postoperative day after open laparotomy and by the 3rd day after laparoscopic surgery.1 The small intestine recovers its normal motility 8–24 h after surgery; the stomach, 24–48 h and the colon from 72 h, the left colon being the last to recover.2 As most surgeons wait for GI function recovery before allowing patients to be fed, POI has become the main cause of delayed hospital discharge after abdominal surgery. In addition, 19–25% of patients will develop prolonged primary ‘paralytic’ POI following major intestinal surgery.1 ,2 The clinical picture of primary POI ranges from oligosymptomatic patients to a full symptom cluster including abdominal pain, nausea and vomiting, abdominal distension and bloating, delayed passage of flatus and stool, and inability to progress to an oral diet. Diagnosis of POI relies on identification of these clinical features but diagnosis by abdominal auscultation for return of bowel sounds or passage …