human
***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The benefits of some ancillary techniques of cholecystectomy are exaggerated by retrospective study of selected patients . Therefore , the authors performed a prospect i ve , r and omized study of 100 consecutive patients who underwent simple elective cholecystectomy for chronic cholecystitis and cholelithiasis . No patient was excluded because of incomplete hemostasis or fear of bile leakage . The frequency of pulmonary complications and wound infections was independent of the type of incision -- vertical or subcostal . Peritoneal drainage was found to be unnecessary . Short-term drainage may increase the frequency of postoperative fever , but did not increase pulmonary complications or wound infections . In these patients , intra-abdominal sepsis is rare ; wound infections were uncommon and the gallbladder bile was usually sterile and not the cause of postoperative infection 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 Closed-suction drainage was compared prospect ively to open , passive drainage ( Penrose drains ) in 128 patients undergoing cholecystectomy . Patients were r and omized at the time of operation to receive either closed-suction drains ( Group I , 67 patients ) or Penrose drains ( Group II , 61 patients ) . The preoperative clinical parameters of the two groups were similar . The patients in Group I when compared with those in Group II had a shorter duration of drainage ( 3.3 days and 4.1 days , respectively , p less than 0.01 ) , a lesser volume of drainage in the first 48 hours postoperatively ( 78 ml and 132 ml , respectively , p less than 0.001 ) , a decreased incidence of fever on the night of operation ( 24 of 67 patients and 39 of 61 patients , respectively , p less than 0.05 ) and on the first postoperative day ( 26 of 67 patients and 32 of 61 patients , respectively , p less than 0.05 ) , and a lower leukocyte count on the first postoperative day ( 12,000 cells/mm3 and 14,100 cells/mm3 , respectively , 0.05 less than p less than 0.1 ) . Patients in Group I tended to have a lower rate of wound infection ( 1 of 67 patients versus 5 of 61 patients in Group II , 0.05 less than p less than 0.1 ) and had a much lower incidence of drain site tenderness ( 8 of 67 patients in Group I versus 24 of 61 patients in Group II , p less than 0.05 ) . This study demonstrates the superiority of closed-suction drains over open , passive drains after cholecystectomy 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 Although laparoscopic cholecystectomy has rapidly developed in the treatment of gall bladder disease in the absence of controlled clinical trial data its outcome parameters compared with open cholecystectomy remain unclear . A prospect i ve audit of the introduction of laparoscopic cholecystectomy in the west of Scotl and over a two year period was carried out to attempt to assess this new procedure . A total of 45 surgeons in 19 hospitals performing laparoscopic cholecystectomy su bmi tted prospect i ve data from September 1990 - 1992 . A total of 2285 cholecystectomies were audited ( a completed data collection rate of 99 % ) . Laparoscopic cholecystectomy was attempted in 1683 ( 74 % ) patients and completed in 1448 patients ( median conversion rate to the open procedure 17 % ) . The median operation time in the completed laparoscopic cholecystectomy patients was 100 minutes ( range 30 - 330 ) and overall hospital stay three days ( 1 - 33 ) . There were nine deaths ( 0.5 % ) after laparoscopic cholecystectomy although only two were directly attributable to the laparoscopic procedure . In the laparoscopic cholecystectomy group there were 99 complications ( 5.9 % ) , 53 ( 3 % ) of these were major requiring further invasive intervention . Forty patients ( 2.4 % ) required early or delayed laparotomy for major complications such as bleeding or bile duct injuries . There were 11 ( 0.7 % ) bile duct injuries in the laparoscopic cholecystectomy series , five were noted during the initial procedure and six were recognised later result ing from jaundice or bile leaks . Ductal injuries occurred after a median of 20 laparoscopic cholecystectomies . In conclusion laparoscopic cholecystectomy has rapidly replaced open cholecystectomy in the treatment of gall bladder disease . Although the overall death and complication rate associated with laparoscopic cholecystectomy is similar to open cholecystectomy , the bile duct injury rate is higher The subhepatic placement of prophylactic drains following cholecystectomy remains a common practice despite studies demonstrating the safety of omitting such drains . The accumulation and fate of subhepatic fluid constitute the chief concern . In a prospect i ve comparative study , 76 patients were r and omized into drained and non-drained groups . Postoperative ultrasonographic studies showed no localized fluid accumulations in the majority of instances . Small accumulations of fluid in the gallbladder bed were demonstrated on the initial postoperative sonograms in nine patients in the two groups . Long-term patient follow-up confirmed such fluid , which remained stable or decreased in size , to be clinical ly insignificant In this prospect i ve r and omized study , the influence of an intraperitoneal drain on the incidence and clinical significance of subhepatic collection s occurring in patients after acute or elective cholecystectomy was assessed by ultrasound examination . A total of 112 patients entered the study , of whom 54 received a drain .  There was no significant difference between the drainage and the non‐drainage groups with respect to mean age or sex distribution , the number of patients in whom the gallbladder bed was formally closed ( 27 versus 21 ) nor in the number of acute cholecystectomies performed in either group ( 12 versus 13 ) . Ultrasound detected 10 ( 18 per cent ) collection s in the drainage group and only one ( 1·8 per cent ) in the non‐drainage group ( P < 0·01 , χ2 test ) . None of the collection s required any further treatment and no morbidity occurred that was directly attributable to the presence of the retained fluid . These results suggest that rather than preventing fluid collection s , suction drains may predispose to the development of subhepatic collection s after cholecystectomy Daily ultrasonography of the gallbladder bed was performed in patients with suction or passive tube drains after elective cholecystectomy . A total of 19 patients was r and omized to suction drainage and 17 to passive tube drainage .  A policy of early drain removal was followed . No significant difference was found between the volume drained and the size of collection detected in either group . Significant bile leaks were detected and were adequately drained by suction and passive tube drains . There were no complications from drains . In view of these findings , we advocate short-term drainage of the gallbladder bed after both open and laparoscopic cholecystectomy using the drain of the surgeon 's choice The efficacy of low pressure , high pressure and passive drainage systems have been compared after cholecystectomy .  Symptoms of pain , discomfort and nausea were compared using linear analogue scales and spirometry was used to examine pre-operative and postoperative respiratory function . The low pressure suction drain removed an intraperitoneal marker , gentamicin , more effectively than the high pressure suction drain , but not more effectively than the passive drain . There were no differences in postoperative respiratory function nor in the amount of pain or discomfort between the groups . The passive drain group reported less nausea than the suction drain groups . If a negative pressure drainage system is to be used , a low pressure suction drain should be used in preference to a high pressure system One hundred eighty-four patients who underwent biliary surgery were r and omly allocated to four groups arranaed in a 2 by 2 design . In 92 patients the drain was brought out through the wound and in the other 92 through a stab incision . In half of the patients in each group the drain was connected to a suction system and in the other half to a sterile bag . Suction was found to impair rather than enhance intraperitoneal drainage . In patients who underwent elective cholecystectomy and early operation for acute cholecystitis , the amount of discharge was more than twice as large when suction was omitted than when it was applied . After common duct operations the amount of discharge was very large and there was little difference in cases with and without suction . Prolonged drainage , static or suction , result ed in an increase in the serum haptoglobin level . Analysis of out data suggested that after a few days the drain starts to act as a traumatic stimulus . No difference was found between cases with the drain brought out through a stab incision and those with the drain brought out through the main wound . A number of studies have ascertained the superiority of closed to open drainage . The results of the present trial lead us to recommend that after biliary surgery the closed us to recommend that after biliary surgery the closed drain should not be connected to a suction apparatus and that after elective cholecystectomy the drain should preferably be removed after a few days OBJECTIVES To analyze sources search ed in Cochrane review s , to determine the proportion of trials included in review s that are indexed in major data bases , and to compare the quality of these trials with those from other sources . METHODS All new systematic review s in the Cochrane Library , Issue1 2001 , that were restricted to r and omized controlled trials ( RCTs ) or quasi- RCTs were selected . The sources search ed in the review s were recorded , and the trials included were checked to see whether they were indexed in four major data bases . Trials not indexed were checked to determine how they could be identified . The quality of trials found in major data bases was compared with those found from other sources . RESULTS The range in the number of data bases search ed per review ranged between one and twenty-seven . The proportion of the trials in the four data bases were Cochrane Controlled Trials Register = 78.5 % , M 
    Output:
    
agent
We found no significant differences between different types of drains .
Drains increase the harms to the patient without providing any additional benefit for patients undergoing open cholecystectomy and should be avoided in open cholecystectomy
***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The benefits of some ancillary techniques of cholecystectomy are exaggerated by retrospective study of selected patients . Therefore , the authors performed a prospect i ve , r and omized study of 100 consecutive patients who underwent simple elective cholecystectomy for chronic cholecystitis and cholelithiasis . No patient was excluded because of incomplete hemostasis or fear of bile leakage . The frequency of pulmonary complications and wound infections was independent of the type of incision -- vertical or subcostal . Peritoneal drainage was found to be unnecessary . Short-term drainage may increase the frequency of postoperative fever , but did not increase pulmonary complications or wound infections . In these patients , intra-abdominal sepsis is rare ; wound infections were uncommon and the gallbladder bile was usually sterile and not the cause of postoperative infection 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 Closed-suction drainage was compared prospect ively to open , passive drainage ( Penrose drains ) in 128 patients undergoing cholecystectomy . Patients were r and omized at the time of operation to receive either closed-suction drains ( Group I , 67 patients ) or Penrose drains ( Group II , 61 patients ) . The preoperative clinical parameters of the two groups were similar . The patients in Group I when compared with those in Group II had a shorter duration of drainage ( 3.3 days and 4.1 days , respectively , p less than 0.01 ) , a lesser volume of drainage in the first 48 hours postoperatively ( 78 ml and 132 ml , respectively , p less than 0.001 ) , a decreased incidence of fever on the night of operation ( 24 of 67 patients and 39 of 61 patients , respectively , p less than 0.05 ) and on the first postoperative day ( 26 of 67 patients and 32 of 61 patients , respectively , p less than 0.05 ) , and a lower leukocyte count on the first postoperative day ( 12,000 cells/mm3 and 14,100 cells/mm3 , respectively , 0.05 less than p less than 0.1 ) . Patients in Group I tended to have a lower rate of wound infection ( 1 of 67 patients versus 5 of 61 patients in Group II , 0.05 less than p less than 0.1 ) and had a much lower incidence of drain site tenderness ( 8 of 67 patients in Group I versus 24 of 61 patients in Group II , p less than 0.05 ) . This study demonstrates the superiority of closed-suction drains over open , passive drains after cholecystectomy 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 Although laparoscopic cholecystectomy has rapidly developed in the treatment of gall bladder disease in the absence of controlled clinical trial data its outcome parameters compared with open cholecystectomy remain unclear . A prospect i ve audit of the introduction of laparoscopic cholecystectomy in the west of Scotl and over a two year period was carried out to attempt to assess this new procedure . A total of 45 surgeons in 19 hospitals performing laparoscopic cholecystectomy su bmi tted prospect i ve data from September 1990 - 1992 . A total of 2285 cholecystectomies were audited ( a completed data collection rate of 99 % ) . Laparoscopic cholecystectomy was attempted in 1683 ( 74 % ) patients and completed in 1448 patients ( median conversion rate to the open procedure 17 % ) . The median operation time in the completed laparoscopic cholecystectomy patients was 100 minutes ( range 30 - 330 ) and overall hospital stay three days ( 1 - 33 ) . There were nine deaths ( 0.5 % ) after laparoscopic cholecystectomy although only two were directly attributable to the laparoscopic procedure . In the laparoscopic cholecystectomy group there were 99 complications ( 5.9 % ) , 53 ( 3 % ) of these were major requiring further invasive intervention . Forty patients ( 2.4 % ) required early or delayed laparotomy for major complications such as bleeding or bile duct injuries . There were 11 ( 0.7 % ) bile duct injuries in the laparoscopic cholecystectomy series , five were noted during the initial procedure and six were recognised later result ing from jaundice or bile leaks . Ductal injuries occurred after a median of 20 laparoscopic cholecystectomies . In conclusion laparoscopic cholecystectomy has rapidly replaced open cholecystectomy in the treatment of gall bladder disease . Although the overall death and complication rate associated with laparoscopic cholecystectomy is similar to open cholecystectomy , the bile duct injury rate is higher The subhepatic placement of prophylactic drains following cholecystectomy remains a common practice despite studies demonstrating the safety of omitting such drains . The accumulation and fate of subhepatic fluid constitute the chief concern . In a prospect i ve comparative study , 76 patients were r and omized into drained and non-drained groups . Postoperative ultrasonographic studies showed no localized fluid accumulations in the majority of instances . Small accumulations of fluid in the gallbladder bed were demonstrated on the initial postoperative sonograms in nine patients in the two groups . Long-term patient follow-up confirmed such fluid , which remained stable or decreased in size , to be clinical ly insignificant In this prospect i ve r and omized study , the influence of an intraperitoneal drain on the incidence and clinical significance of subhepatic collection s occurring in patients after acute or elective cholecystectomy was assessed by ultrasound examination . A total of 112 patients entered the study , of whom 54 received a drain .  There was no significant difference between the drainage and the non‐drainage groups with respect to mean age or sex distribution , the number of patients in whom the gallbladder bed was formally closed ( 27 versus 21 ) nor in the number of acute cholecystectomies performed in either group ( 12 versus 13 ) . Ultrasound detected 10 ( 18 per cent ) collection s in the drainage group and only one ( 1·8 per cent ) in the non‐drainage group ( P < 0·01 , χ2 test ) . None of the collection s required any further treatment and no morbidity occurred that was directly attributable to the presence of the retained fluid . These results suggest that rather than preventing fluid collection s , suction drains may predispose to the development of subhepatic collection s after cholecystectomy Daily ultrasonography of the gallbladder bed was performed in patients with suction or passive tube drains after elective cholecystectomy . A total of 19 patients was r and omized to suction drainage and 17 to passive tube drainage .  A policy of early drain removal was followed . No significant difference was found between the volume drained and the size of collection detected in either group . Significant bile leaks were detected and were adequately drained by suction and passive tube drains . There were no complications from drains . In view of these findings , we advocate short-term drainage of the gallbladder bed after both open and laparoscopic cholecystectomy using the drain of the surgeon 's choice The efficacy of low pressure , high pressure and passive drainage systems have been compared after cholecystectomy .  Symptoms of pain , discomfort and nausea were compared using linear analogue scales and spirometry was used to examine pre-operative and postoperative respiratory function . The low pressure suction drain removed an intraperitoneal marker , gentamicin , more effectively than the high pressure suction drain , but not more effectively than the passive drain . There were no differences in postoperative respiratory function nor in the amount of pain or discomfort between the groups . The passive drain group reported less nausea than the suction drain groups . If a negative pressure drainage system is to be used , a low pressure suction drain should be used in preference to a high pressure system One hundred eighty-four patients who underwent biliary surgery were r and omly allocated to four groups arranaed in a 2 by 2 design . In 92 patients the drain was brought out through the wound and in the other 92 through a stab incision . In half of the patients in each group the drain was connected to a suction system and in the other half to a sterile bag . Suction was found to impair rather than enhance intraperitoneal drainage . In patients who underwent elective cholecystectomy and early operation for acute cholecystitis , the amount of discharge was more than twice as large when suction was omitted than when it was applied . After common duct operations the amount of discharge was very large and there was little difference in cases with and without suction . Prolonged drainage , static or suction , result ed in an increase in the serum haptoglobin level . Analysis of out data suggested that after a few days the drain starts to act as a traumatic stimulus . No difference was found between cases with the drain brought out through a stab incision and those with the drain brought out through the main wound . A number of studies have ascertained the superiority of closed to open drainage . The results of the present trial lead us to recommend that after biliary surgery the closed us to recommend that after biliary surgery the closed drain should not be connected to a suction apparatus and that after elective cholecystectomy the drain should preferably be removed after a few days OBJECTIVES To analyze sources search ed in Cochrane review s , to determine the proportion of trials included in review s that are indexed in major data bases , and to compare the quality of these trials with those from other sources . METHODS All new systematic review s in the Cochrane Library , Issue1 2001 , that were restricted to r and omized controlled trials ( RCTs ) or quasi- RCTs were selected . The sources search ed in the review s were recorded , and the trials included were checked to see whether they were indexed in four major data bases . Trials not indexed were checked to determine how they could be identified . The quality of trials found in major data bases was compared with those found from other sources . RESULTS The range in the number of data bases search ed per review ranged between one and twenty-seven . The proportion of the trials in the four data bases were Cochrane Controlled Trials Register = 78.5 % , M 
    Output:
    