***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: BACKGROUND The benefits of preoperative biliary drainage , which was introduced to improve the postoperative outcome in patients with obstructive jaundice caused by a tumor of the pancreatic head , are unclear . METHODS In this multicenter , r and omized trial , we compared preoperative biliary drainage with surgery alone for patients with cancer of the pancreatic head . Patients with obstructive jaundice and a bilirubin level of 40 to 250 micromol per liter ( 2.3 to 14.6 mg per deciliter ) were r and omly assigned to undergo either preoperative biliary drainage for 4 to 6 weeks , followed by surgery , or surgery alone within 1 week after diagnosis . Preoperative biliary drainage was attempted primarily with the placement of an endoprosthesis by means of endoscopic retro grade cholangiopancreatography . The primary outcome was the rate of serious complications within 120 days after r and omization . RESULTS We enrolled 202 patients ; 96 were assigned to undergo early surgery and 106 to undergo preoperative biliary drainage ; 6 patients were excluded from the analysis . The rates of serious complications were 39 % ( 37 patients ) in the early-surgery group and 74 % ( 75 patients ) in the biliary-drainage group ( relative risk in the early-surgery group , 0.54 ; 95 % confidence interval [ CI ] , 0.41 to 0.71 ; P<0.001 ) . Preoperative biliary drainage was successful in 96 patients ( 94 % ) after one or more attempts , with complications in 47 patients ( 46 % ) . Surgery-related complications occurred in 35 patients ( 37 % ) in the early-surgery group and in 48 patients ( 47 % ) in the biliary-drainage group ( relative risk , 0.79 ; 95 % CI , 0.57 to 1.11 ; P=0.14 ) . Mortality and the length of hospital stay did not differ significantly between the two groups . CONCLUSIONS Routine preoperative biliary drainage in patients undergoing surgery for cancer of the pancreatic head increases the rate of complications . ( Current Controlled Trials number , IS RCT N31939699 . BACKGROUND A preoperative biliary stent is commonly used after the initial evaluation of the patient with a periampullary mass . OBJECTIVE To evaluate the effect of a preoperative biliary stent on operative difficulty , postoperative complications , and length of hospital stay after a pancreatoduodenectomy . DESIGN A retrospective review of a prospect ively collected consecutive series . SETTING The Memorial Sloan-Kettering Cancer Center 's Surgical Service , New York , NY . PATIENTS AND METHODS Seventy-four patients underwent pancreatoduodenectomy between March 1 , 1994 , and February 15 , 1996 . Thirty-five did not receive a biliary stent , and 39 received a biliary stent prior to medical evaluation . We analyzed patient , nutritional , laboratory , and operating room factors . Univariate analysis was by Student t test , chi2 test , and Fisher exact test ; multivariate analysis was by logistic regression . Significance was defined at P<.05 . MAIN OUTCOME MEASURES Operative time , amount of blood loss , complications , and length of hospital stay . Wound complications were defined as cellulitis , superficial infections , and deep infections . Intra-abdominal complications were defined as intra-abdominal abscesses and pancreatic or biliary fistula . RESULTS Groups were equivalent for tumor size , risk of comorbidity , time spent in the operating room , and amount of blood loss . There was 1 perioperative death . Patients with a stent had significantly lower bilirubin ( P<.03 ) and aspartate aminotransferase ( P<.04 ) levels and a significantly increased risk of nodal positivity ( P<.05 ) . The patients with a biliary stent had an increased risk of wound or abdominal complications on univariate ( P<.003 ) and multivariate ( P<.02 ) analysis and tended toward a prolonged hospital stay ( P<.04 , Wilcoxon signed rank test ) . CONCLUSIONS A preoperative biliary stent was associated with an increased risk of wound or intra-abdominal complications ; a stent may prolong the length of hospital stay . However , length of time under anesthesia , amount of blood loss , and transfusion requirements were not altered . A biliary stent should be used with a high degree of selectivity in the management of patients with resectable periampullary masses OBJECTIVE To find out factors that may influence the mortality after Whipple 's operation , whether duct to mucosa anastomosis is better than classic " dunking " pancreaticojejunostomy and whether age over 70 is a contraindication for this procedure . DESIGN Prospect ively r and omised study . SETTING Teaching hospital , Taiwan , R.O.C. PATIENTS 93 patients with periampullary cancer undergoing Whipple 's operation were r and omly divided into two groups . Forty-six with periampullary cancer underwent invaginating pancreaticojejunostomy , and 47 patients underwent duct to mucosa anastomosis for reconstruction . MAIN OUTCOME MEASURES Mortality and morbidity were compared between two groups . RESULTS The over all mortality was 8 % ( 7/93 ) . An albumin concentration of less than 30 g/L before operation and operative blood loss influenced the surgical mortality both in the univariate and multivariate analysis . Age over 70 years was not a factor . Patients with duct to mucosa anastomoses had a leak rate of 4 % ( 2/47 ) , morbidity of 21 % ( 10/47 ) and mortality of 6 % ( 3/47 ) . Patients with an invaginated pancreaticojejunostomy had a leak rate of 15 % ( 7/46 ) , morbidity of 33 % ( 15/46 ) , and mortality of 9 % ( 4/46 ) . The need for total parenteral nutrition in the invaginated group ( 33 % ) was statistically greater than in the other group ( 11 % ) ( p = 0.01 ) . CONCLUSIONS The morbidity and mortality of pancreaticoduodenectomy for periampullary cancer although slightly greater for patients over the age of 70 are acceptable . The factors that may influence the mortality are an albumin concentration of less then 30 g/L and the amount of blood lost during operation . The duct to mucosa anastomosis is a safe procedure , which has a lower leak rate and less need for total parenteral nutrition than pancreaticojejunostomy 57 patients with obstructive jaundice were r and omly allocated to surgery with preoperative external biliary drainage ( 29 patients ) and without preoperative external biliary drainage ( 28 patients ) . 22 patients ultimately underwent laparotomy after a mean of 11.7 days of drainage and 25 had surgery without preoperative drainage . The postoperative complication rate was low and similar in both groups but complications associated with the drainage procedure were substantial . Perioperative mortality was 4/28 ( 14 % ) in the drainage group and 4/27 ( 15 % ) in the non-drainage group . There seems to be no advantage associated with routine preoperative external biliary drainage before surgery for obstructive jaundice OBJECTIVE To analyze the  morbidity and mortality after radical and palliative pancreatic cancer surgery in Norway , especially the risk factors . SUMMARY BACKGROUND DATA A prospect i ve multicenter study between 1984 - 1987 including only histologically or cytologically verified adenocarcinoma of the pancreas ( N = 442 ) or the papilla of Vater ( N = 30 ) ; 84 patients ( 19 % ) with pancreatic carcinoma and 24 patients ( 80 % ) with papilla carcinoma underwent radical operations .  A palliative procedure was performed in 252 patients ( 53 % ) . METHODS Clinical data , surgical procedures and the following morbidity and mortality were recorded on st and ardized forms . The risk factors were analyzed by a logistic multiple regression model . RESULTS The morbidity , reoperation , and mortality rates were 43 , 18 , and 11 % after radical surgery and 23 , 4 , and 14 % after palliative surgery .  Karnofsky 's index was the sole independent risk factor for death after radical surgery .  Splenectomy , age , and TNM stage influenced morbidity . Diabetes , Karnofsky 's index , and liver metastases were risk factors in palliative surgery . CONCLUSIONS The morbidity and mortality risks were comparable between total pancreatectomy and a Whipple 's procedure and between biliary and a double bypass . Preoperative biliary drainage had no impact on the risks and may be ab and oned . High age is a relative and a low Karnofsky 's index an absolute contraindication for radical surgery . Nonsurgical palliation of jaundice should be considered according to the presence of independent risk factors BACKGROUND Patients with obstructive jaundice undergoing surgical procedures have a significant risk of morbidity and mortality . The role of preoperative percutaneous transhepatic biliary drainage ( PTBD ) was evaluated in a r and omized trial . METHODS A total of 40 patients were assigned to either preoperative PTBD ( n = 20 ) , or surgery alone ( n = 20 ) . PTBD was performed under ultrasound guidance . There were no major complications related to the procedure . RESULTS Ultrasound guided drainage was a successful and safe method of preoperative biliary decompression . There was a marked relief from pruritus and significant reduction of hyperbilirubinaemia from a mean of 386.48 mumol/L to 116.10 mumol/L ( p < 0.001 ) . Mean duration of drainage was 42.5 days . Postoperative complications occurred in five patients in PTBD group ( 25 % ) compared to 11 patients ( 55 % ) in the control group . One death ( 5 % ) occurred in PTBD group compared to four deaths ( 20 % ) in the control group ( significant at 5 % level with probability 0.2 ) . CONCLUSIONS Ultrasound guided drainage is a useful preoperative supportive measure in preparing deeply jaundiced patients for surgery and permits hepatic function to return to a near normal state preoperatively . The improved results in our study were due to longer duration of drainage Thirty patients with obstructive jaundice with plasma bilirubin values greater than 200 mumol/L were r and omized at the time of  percutaneous transhepatic Cholangiography  to undergo immediate or delayed surgery . The patients who had preoperative percutaneous transhepatic biliary drainage ( PTBD ) for 13.8 + /- 5.8 days had fewer surgical complications than did patients who underwent immediate surgery ( p less than 0.02 ) , although when the complications of PTBD were included this advantage was diminished . Immediate surgery caused greater deterioration of renal function as measured by plasma urea , plasma B 2-microglobulin , phosphate clearance , uric acid clearance , and maximal concentrating ability than occurred after PTBD or delayed surgery . The improvement in phosphate clearance that followed PTBD was sustained through delayed surgical treatment , indicating better tubular function in these patients . This article supports the concept that preoperative PTBD will reduce surgical morbidity and will result in less renal impairment than will immediate surgery . However , the morbidity rates of the PTBD procedure will preclude its wide use It has been suggested that the placement of endoscopic or percutaneous biliary stents prior to pancreaticoduodenectomy increases postoperative morbidity . A retrospective review of a prospect ively collected data base was performed . Patients undergoing preoperative biliary stenting  were compared with patients who did not undergo stenting .  In addition , outcomes after endoscopic and percutaneous stenting were compared . Patients who had undergone operative biliary bypass prior to pancreaticoduodenectomy were excluded from the analysis . Between January 1994 and December 1997,567 patients underwent pancreaticoduodenectomy without prior operative biliaty bypass . Preoperative biliary stenting was performed in 408 patients ( 72 % ) , whereas the remaining 159 patients ( 28 % ) did not undergo biliary stenting . In the stented group , 64 % had stents placed via a percutaneous approach and 36 % had stents placed endoscopically . The stented patients were older ( mean 63.1 years vs. 61.4 years ; P = 0.05 ) and were more likely to be white ( 92 % vs. 82 % ; P = 0.005 ) . Those who had stents placed were more likely to have jaundice ( 67 % vs. 38 % ; P < 0.0001 ) and fever ( 5 % vs. 1 % ; P = 0.03 ) as presenting symptoms . There were no differences in multiple intraoperative parameters when the two groups were compared . Patients who had stems placed had a perioperative mortality rate of 1.7 % compared to 2 
    Output:
    
Conclusions In patients with malignant biliary jaundice requiring surgery , PBD group had significantly less major adverse effects than DS group .
Length of hospital stay and mortality rate were comparable in both the groups