BackgroundThere is no consensus on diagnosis and management of ASBO. Initial conservative management is usually safe, however proper timing for discontinuing non operative treatment is still controversial. Open surgery or laparoscopy are used without standardized indications.MethodsA panel of 13 international experts with interest and background in ASBO and peritoneal diseases, participated in a consensus conference during the 1st International Congress of the World Society of Emergency Surgery and 9th Peritoneum and Surgery Society meeting, in Bologna, July 1-3, 2010, for developing evidence-based recommendations for diagnosis and management of ASBO. Whenever was a lack of high-level evidence, the working group formulated guidelines by obtaining consensus.RecommendationsIn absence of signs of strangulation and history of persistent vomiting or combined CT scan signs (free fluid, mesenteric oedema, small bowel faeces sign, devascularized bowel) patients with partial ASBO can be managed safely with NOM and tube decompression (either with long or NG) should be attempted. These patients are good candidates for Water Soluble Contrast Medium (WSCM) with both diagnostic and therapeutic purposes. The appearance of water-soluble contrast in the colon on X-ray within 24 hours from administration predicts resolution. WSCM may be administered either orally or via NGT (50-150 ml) both immediately at admission or after an initial attempt of conservative treatment of 48 hours. The use of WSCM for ASBO is safe and reduces need for surgery, time to resolution and hospital stay.NOM, in absence of signs of strangulation or peritonitis, can be prolonged up to 72 hours. After 72 hours of NOM without resolution surgery is recommended.Patients treated non-operatively have shorter hospital stay, but higher recurrence rate and shorter time to re-admission, although the risk of new surgically treated episodes of ASBO is unchanged. Risk factors for recurrences are age <40 years and matted adhesions. WSCM does not affect recurrence rates or recurrences needing surgery when compared to traditional conservative treatment.Open surgery is the preferred method for surgical treatment of strangulating ASBO as well as after failed conservative management. In selected patients and with appropriate skills, laparoscopic approach can be attempted using open access technique. Access in the left upper quadrant should be safe. Laparoscopic adhesiolysis should be attempted preferably in case of first episode of SBO and/or anticipated single band. A low threshold for open conversion should be maintained.Peritoneal adhesions should be prevented. Hyaluronic acid-carboxycellulose membrane and icodextrin can reduce incidence of adhesions. Icodextrin may reduce the risk of re-obstruction. HA cannot reduce need of surgery.