The liver produces bile which has many functions, including elimination of waste processed by the liver and digestion of fat. The bile is temporarily stored in the gallbladder (an organ situated underneath the liver) before it reaches the small bowel. Concretions in the gallbladder are called gallstones. Gallstones are present in about 5% to 25% of the adult western population. Between 2% and 4% become symptomatic in a year. The symptoms include pain related to the gallbladder (biliary colic), inflammation of the gallbladder (cholecystitis), obstruction to the flow of bile from the liver and gallbladder into the small bowel resulting in jaundice (yellowish discolourisation of the body usually most prominently noticed in the white of the eye, which turns yellow), bile infection (cholangitis), and inflammation of the pancreas, an organ which secretes digestive juices and harbours the insulin secreting cells which maintain blood sugar level (pancreatitis). Removal of the gallbladder (cholecystectomy) is currently considered the best treatment option for patients with symptomatic gallstones. This is generally performed by key-hole surgery (laparoscopic cholecystectomy). Drain is a tube that is left inside the tummy to allow drainage of fluids to outside the tummy. Some surgeons have routinely drained after laparoscopic cholecystectomy because of the fear of collection of bile or blood requiring re-operation. As the name indicates, the drain may drain out these collections to the exterior, thereby avoiding open surgery. However, routine use of drains may necessitate the patient to stay overnight or require drain removal after discharge both of which increase resource utilisation in this era of day surgery (where patients are admitted and discharged on the same day of surgery). The review authors set out to determine whether it is preferable to use routine drainage after laparoscopic cholecystectomy. A systematic search of medical literature was performed in order to identify studies which provided information on the above question. The authors obtained information from randomised trials only since such types of trials provide the best information if conducted well. Two authors independently identified the trials and collected the information.

A total of 1831 participants received drain (915 patients) versus 'no drain' (916 patients) in 12 trials included in this review. The decision of whether the patients received drain or not was determined by a method similar to toss of a coin. Only two trials including 199 patients were of low risk of bias (free from errors in study design that can result in wrong conclusions, leading to overestimation of benefits and to underestimation of harms of the drainage or no drainage). Nine of the 12 trials included patients who underwent planned operations. The average age of participants in the trials ranged between 48 years and 63 years in the 10 trials that provided this information. The proportion of females ranged between 55.0% and 79.0% in the 11 trials that provided this information. There was no significant or clinically important differences in the short-term mortality, serious complications, quality of life, length of hospital stay, operating time, return to normal activity, or return to work in the trials that reported these outcomes. The proportion of patients who were discharged as day-procedure laparoscopic cholecystectomy seemed significantly lower in the drain group than in the 'no drain' group in one trial of high risk of bias involving 68 participants. Currently, there is no evidence to support the use of drain after laparoscopic cholecystectomy. Further well-designed randomised clinical trials are necessary.