Most surgeons put the drain after cholecystectomy with the hope that it would aid in the detection of postoperative bleeding or bile leakage and the prevention of intra-abdominal infection. However, several studies have shown that drains are not necessary after cholecystectomy. The American Society for Gastrointestinal Endoscopy (ASGE) guidelines recommend placing a drainage tube after any form of gastrointestinal endoscopic procedure to prevent serious complications such as perforation or obstruction. In addition, the society recommends draining abdominal fluid collections after exploratory laparotomy or ultrasonography-guided liver biopsy to reduce the risk of infection. Finally, the society states that there is insufficient evidence to determine whether drainage improves clinical outcomes after acute pancreatitis. Drains are useful after certain types of abdominal surgery because the intestines and other organs may bleed or leak bile into the abdomen after their blood supply has been cut off. A drain can help physicians see this bleeding or bile leakage before they become problems that require further treatment. Drain placement is also helpful in reducing the risk of infection. The intestines absorb many bacteria from the digestive system through their lining (mucosa). These bacteria trigger an immune response that helps fight infection.