***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Objective This prospect i ve r and omized study determined the influence of closed-suction drainage on the incidence of postoperative complications after elective hepatic resection . Summary Background Data Routine drainage is no longer advocated after several intra-abdominal surgical procedures . Methods A series of 81 patients who underwent elective hepatic resection were r and omly allocated to either a nondrainage group ( n = 39 ) and a drainage group with closed-suction drainage ( n = 42 ) . Indications for resection were 42 benign lesions and 39 malignant tumors , including 19 with cirrhosis . Major hepatic resection was performed in 25 patients and minor resection , in 56 . All patients underwent ultrasonography with puncture for bacteriologic cultures of all fluid collection s within the first 5 postoperative days . Results One patient died in each group . Ultrasonography found a significantly higher rate of subphrenic collection s in the drainage group compared with the nondrainage group ( respectively , 36 % vs. 15 % , p < 0.05 ) . These collection s were more frequently infected in the drainage group ( n = 6 ) than in the nondrainage group ( n = 2 ) . After major liver resection , the rate of intra-abdominal postoperative complications ( i.e. , subphrenic fluid collection s , hematomas , and bilomas ) was similar between the two groups . Conclusion Minor liver resection is safer without drainage . Major liver resection can be performed with or without abdominal drainage Abstract During the 24-month period commencing January 1975 , 200 patients underwent elective cholecystectomy for chronic cholecystitis . According to a prospect i ve r and omized protocol , 100 patients were drained and an identical number were not drained . The two groups were similar with respect to age , weight , diabetic history , and all other measured clinical parameters . Patients who were not drained had less postoperative fever in terms of actual temperature elevation and duration of fever and were discharged from the hospital earlier . There was no difference in the incidence of wound infection or other complications between the two groups . This study confirms that elective cholecystectomy without drainage of the subhepatic space can be done safely and that less postoperative fever and shorter hospitalization can be expected Consecutive patients undergoing emergency appendectomy ( 283 ) or urgent cholecystectomy ( 51 ) were prospect ively studied for the development of postoperative incisional or peritoneal sepsis . Severity of the original peritoneal infection was carefully recorded , while use of a Penrose dam to drain the peritoneum was r and omized according to pre-assigned hospital number . Both aerobic and anaerobic cultures were taken from the abdomen at the time of operation as well as from all postoperative infectious foci . Results demonstrated no essential differences in incidence of wound and peritoneal infection following  appendectomy  for simple or suppurative appendicitis ( 187 ) or following  cholecystectomy  for acute cholecystitis ( 51 ) . However , with gangrenous or perforative appendicitis ( 94 ) , incisional and intra-abdominal infection rates were 43 % and 45 % , respectively , when a drain was used ; yet only 29 and 13 % , respectively , without a drain . These latter differences were significant ( p < 0.001 ) . In addition , intra-abdominal abscesses were three times as likely to drain through the incision than along any tract provided by the rubber conduit . Cultures revealed that hospital pathogens accounted for a greater proportion of wound and peritoneal sepsis after cholecystectomy and appendectomy for simple or suppurative appendicitis if a drain had been inserted than if managed otherwise . By contrast , a mixed bacterial flora was responsible for most infections following appendectomy for gangrenous or perforated appendicitis , irrespective as to use of a drain Some surgeons drain the gallbladder bed routinely , some selectively and some not at all . We aim ed to clarify this confusion by entering 155 consecutive patients undergoing emergency and elective cholecystectomy without exploration of the common bile duct into a r and om control clinical trial . In 78 patients a 3 mm suction drain was left in the gallbladder bed and in 77 the abdomen was closed without drainage . There were no withdrawals , one death ( in the drainage group ) from myocardial infa rct ion and one intraperitoneal abscess complicating postoperative pancreatitis ( in the no‐drainage group ) . Other events studied were postoperative pyrexia , wound infection , respiratory tract infection and duration of hospital stay . In none of these did the two groups differ either clinical ly or statistically . We conclude that drainage or non‐drainage of the gallbladder bed must remain a matter of individual preference Objective : The aim of this study was to determine whether abdominal drainage is beneficial after elective hepatic resection in patients with underlying chronic liver diseases . Summary Background Data : Traditionally , in patients with chronic liver diseases , an abdominal drainage catheter is routinely inserted after hepatic resection to drain ascitic fluid and to detect postoperative hemorrhage and bile leakage . However , the benefits of this surgical practice have not been evaluated prospect ively . Patients and Methods : Between January 1999 and March 2002 , 104 patients who had underlying chronic liver diseases were prospect ively r and omized to have either closed suction abdominal drainage ( drainage group  , n = 52 ) or no drainage ( nondrainage group , n = 52 ) after elective hepatic resection .  The operative outcomes of the 2 groups of patients were compared . Results : Fifty-seven ( 55 % ) patients had major hepatic resection with resection of 3 Coiunaud 's segments or more . Sixty-nine ( 66 % ) patients had liver cirrhosis and 35 ( 34 % ) had chronic hepatitis . Demographic , surgical , and pathologic details were similar between both groups . The primary indication for hepatic resection was hepatocellular carcinoma ( n = 100 , 96 % ) . There was no difference in hospital mortality between the 2 groups of patients ( drainage group , 6 % vs. nondrainage group , 2 % ; P = 0.618 ) . However , there was a significantly higher overall operative morbidity in the drainage group ( 73 % vs. 38 % , P < 0.001 ) . This was related to a significantly higher incidence of wound complications in the drainage group compared with the nondrainage group ( 62 % vs. 21 % , P < 0.001 ) . In addition , a trend toward a higher incidence of septic complications in the drainage group was observed ( 33 % vs. 17 % , P = 0.07 ) . The mean ( ± st and ard error of mean ) postoperative hospital stay of the drainage group was 19.0 ± 2.2 days , which was significantly longer than that of the nondrainage group ( 12.5 ± 1.1 days , P = 0.005 ) . With a median follow-up of 15 months , none of the 51 patients with hepatocellular carcinoma in the drainage group developed metastasis at the drain sites . On multivariate analysis ,  abdominal drainage , underlying liver cirrhosis , major hepatic resection , and intraoperative blood loss of > 1.5L were independent and significant factors associated with postoperative morbidity . Conclusion : Routine abdominal drainage after hepatic resection is contraindicated in patients with  chronic liver diseases BACKGROUND It was hypothesized that routine operative drainage is unnecessary for elective hepatic resection . METHODS A review was made of the clinical records of patients undergoing liver resection at a tertiary referral hepatobiliary surgery center since the conclusion in April of 1994 of our previous r and omized drainage trial . The main outcome measures were  operative drainage versus no operative drainage  assessed for possible association with diagnoses , extent of hepatectomy , hospital course , and postoperative radiologic percutaneous drainage procedures . RESULTS Of 1,165 patients , 184 were operatively drained with closed drains according to specific practice criteria and 981 were not subject to operative drainage .  Patients who were not operatively drained had length of stay ( 10.1 days ) , mortality ( 2 % ) , and complication rate ( 34 % ) comparable with the nondrained patients in the previous r and omized trial . Ten percent of these patients required postoperative percutaneous drainage . Patients who were operatively drained were a group who were at higher risk for biliary leakage or infections and consequently had a significantly longer hospital stay , greater mortality , higher complication rate , and required a greater number of percutaneous abdominal drainages . CONCLUSIONS The 84 % of patients not operatively drained had no greater adverse outcome . After hepatic resection , routine drainage of the abdomen is unnecessary Closed suction drains after pancreaticoduodenectomy are theoretically used to drain potential collection s and anastomotic leaks . It is unknown whether such drains are effective , harmful , or affect the outcome after this operation . Eighty-nine consecutive patients underwent pancreaticoduodenectomy for presumed periampullary malignancy and were retrospectively review ed . Thirty-eight had no intraabdominal drains and 51 had drains placed at the conclusion of the operation . We analyzed patient , nutritional , laboratory , and operating room factors with end points being complications and length of hospital stay . Intra-abdominal complications were defined as intra-abdominal abscess and pancreatic or biliary fistula . Postoperative interventions were defined as CT-guided drainage and reoperation . Analysis was by Student ’s t test and chi-square test . Two of eight surgeons contributed 92 % of the patients without drains . The groups were equivalent with respect to demographic , nutritional , and operative factors . Time under anesthesia was significantly shorter in the group without drains ( P = 0.0001 ) . There was no statistical difference in the rate of fistula , abscess , CT drainage , or length of hospital stay . Intra-abdominal drainage did not significantly alter the risk of fistula , abscess , or reoperation or the necessity for CT-guided intervention after pancreaticoduodenectomy . Routine use of drains after pancreaticoduodenectomy may not be necessary and should be subjected to a r and omized trial To date , there have been no clinical investigations of the usefulness of drains following colonic anastomosis in elective operations . We report a prospect i ve study in which 49 patients were r and omized to have a corrugated silastic drain ( Portex ) placed next to the colonic anastomosis .  These patients were compared with a control group of 57 patients who had no drain .  The two groups were similar in age , sex , diagnosis and site of anastomosis . There was no difference in outcome between the two groups . Anastomotic leakage occurred in six patients in each group . Wound infections were noted in 10 patients in each group . Two patients with a drain and one patient without a drain died from leakage at the anastomosis . This study provides no evidence to support the use of a corrugated drain after anastomosis of the colon OBJECTIVE We investigated the role of drainage in the prevention of complications after elective rectal or anal anastomosis in the pelvis . Anastomotic leakage after colorectal resection is more prevalent when the anastomosis is in the distal or infraperitoneal pelvis than in the abdomen . The benefit of pelvic drains versus their potential harm has been question ed . Drain-related complications include ( 1 ) those possibly benefiting from drainage ( leakage , intra-abdominal infection , bleeding ) and ( 2 ) those possibly caused by drainage ( wound infection or hernia , intestinal obstruction , fistula ) . METHODS Between September 1990 and June 1995 , 494 patients ( 249 men and 245 women ) , mean age 66 + /- 15 ( range 15 to 101 ) years , with either carcinoma , benign tumor , colonic Crohn 's disease , diverticular disease of the sigmoid colon , or another disorder located anywhere from the right colon to the midrectum undergoing resection followed by rectal or anal anastomosis were r and omized to undergo either drainage ( n = 248 ) with 2 multiperforated 14F suction drains or no drainage ( n = 246 ) . The primary end point was the number of patients with one or more postoperative drain-related complications . Secondary end points included severity of these complications as assessed by the rate of related repeat operations and associated deaths as well as extra-abdominally related morbidity and mortality . RESULTS After withdrawal of 2 patients ( 1 in each group ) both groups were comparable with regard to preoperative characteristics and intraoperative findings . The overall leakage rate was 6.3 % with no significant difference between those with or without drainage . There were 18 deaths ( 3.6 % ) , 8 ( 3.2 % ) in those with drainage and 10 ( 4 % ) in those without drainage . Five patients with anastomotic leakage died ( 1 % ) , 3 of whom had drainage . There were 32 repeat operations ( 6.5 % ) 
    Output:
    
RESULTS There is evidence of level 1a that drains  do not reduce complications after hepatic , colonic , or rectal resection with primary anastomosis and appendectomy for any stage of appendicitis .
Drains were even harmful after hepatic resection in chronic liver disease and appendectomy .
In the absence of RCTs , there is a consensus ( evidence level 5 ) about the necessity of prophylactic drainage after esophageal resection and total gastrectomy due to the potential fatal outcome in case of anastomotic and gastric leakage .
Many GI operations can be performed safely without prophylactic drainage .
Drains should be omitted after hepatic , colonic , or rectal resection with primary anastomosis and appendectomy for any stage of appendicitis ( recommendation grade A ) , whereas prophylactic drainage remains indicated after esophageal resection and total gastrectomy ( recommendation grade D ) .