***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: Objectives To evaluate the efficacy and safety of ultrasound-guided percutaneous catheter drainage ( PCD ) treatment for severe acute pancreatitis compared to conservative and conventional surgical treatments . Methods Eighty-one patients with severe acute pancreatitis ( SAP ) were admitted and divided into three groups : forty-nine cases in the conservative therapy group ; nineteen cases in the surgery group ; and thirteen cases in the PCD therapy group . Forty-five patients with a CT severity index ( CTSI ) ≤ 8.0 received conservative treatment . One patient with CTSI = 7.0 underwent surgery . Thirty-five patients with a CTSI > 8.0 were r and omly selected for surgery or PCD treatment . After r and omization , six patients ( four patients in the surgery group and two patients in the PCD group ) were dropped from the study . The total number of patients included in the surgery and PCD groups was sixteen and thirteen , respectively . Results Four patients ( 8.2 % ) in the conservative therapy group died , five patients ( 31.3 % ) in surgery group with a CTSI > 8.0 died , and all patients in the PCD group survived . The mortality rate was lower in the PCD group than in the surgery group ( P = 0.048 ) . The serum C-reactive protein ( CRP ) level recovered more quickly in patients in the PCD group compared to those in the surgery group ( P < 0.001 ) . Conclusions Patients with SAP and a CTSI ≤ 8.0 could be treated with conservative therapy , while patients with a CTSI > 8.0 should be treated with surgery or PCD therapy if the life-threatening complications of extensive fluid collection or necrosis are a factor . However , PCD therapy used in a timely manner for drainage may decrease mortality in patients with SAP , decrease inflammatory mediator release , and avoid incidence of severe sepsis or acute respiratory distress syndrome ( ARDS ) and emergency surgery BACKGROUND Necrotizing pancreatitis with infected necrotic tissue is associated with a high rate of complications and death . St and ard treatment is open necrosectomy . The outcome may be improved by a minimally invasive step-up approach . METHODS In this multicenter study , we r and omly assigned 88 patients with necrotizing pancreatitis and suspected or confirmed infected necrotic tissue to undergo  primary open necrosectomy or a step-up approach to treatment . The step-up approach consisted of percutaneous drainage followed , if necessary , by minimally invasive retroperitoneal necrosectomy . The primary end point was a composite of major complications ( new-onset multiple-organ failure or multiple systemic complications , perforation of a visceral organ or enterocutaneous fistula , or bleeding ) or death . RESULTS The primary end point occurred in 31 of 45 patients ( 69 % ) assigned to open necrosectomy and in 17 of 43 patients ( 40 % ) assigned to the step-up approach ( risk ratio with the step-up approach , 0.57 ; 95 % confidence interval , 0.38 to 0.87 ; P=0.006 ) . Of the patients assigned to the step-up approach , 35 % were treated with percutaneous drainage only . New-onset multiple-organ failure occurred less often in patients assigned to the step-up approach than in those assigned to open necrosectomy ( 12 % vs. 40 % , P=0.002 ) . The rate of death did not differ significantly between groups ( 19 % vs. 16 % , P=0.70 ) . Patients assigned to the step-up approach had a lower rate of incisional hernias ( 7 % vs. 24 % , P=0.03 ) and new-onset diabetes ( 16 % vs. 38 % , P=0.02 ) . CONCLUSIONS A minimally invasive step-up approach , as compared with open necrosectomy , reduced the rate of the composite end point of major complications or death among patients with necrotizing pancreatitis and infected necrotic tissue . ( Current Controlled Trials number , IS RCT N13975868 . BACKGROUND & AIMS Treatment of patients with necrotizing pancreatitis has become more conservative and less invasive , but there are few data from prospect i ve studies to support the efficacy of this change . We performed a prospect i ve multicenter study of treatment outcomes among patients with necrotizing pancreatitis . METHODS We collected data from 639 consecutive patients with necrotizing pancreatitis , from 2004 to 2008 , treated at 21 Dutch hospitals . Data were analyzed for disease severity , interventions ( radiologic , endoscopic , surgical ) , and outcome . RESULTS Overall mortality was 15 % ( n=93 ) . Organ failure occurred in 240 patients ( 38 % ) , with 35 % mortality . Treatment was conservative in 397 patients ( 62 % ) , with 7 % mortality . An intervention was performed in 242 patients ( 38 % ) , with 27 % mortality ; this included early emergency laparotomy in 32 patients ( 5 % ) , with 78 % mortality . Patients with longer times between admission and intervention had lower mortality : 0 to 14 days , 56 % ; 14 to 29 days , 26 % ; and > 29 days , 15 % ( P<.001 ) . A total of 208 patients ( 33 % ) received interventions for infected necrosis , with 19 % mortality .  Catheter drainage was most often performed as the first intervention ( 63 % of cases ) , without additional necrosectomy in 35 % of patients .  Primary catheter drainage  had fewer complications than primary necrosectomy ( 42 % vs 64 % , P=.003 ) . Patients with pancreatic parenchymal necrosis ( n=324 ) , compared with patients with only peripancreatic necrosis ( n=315 ) , had a higher risk of organ failure ( 50 % vs 24 % , P<.001 ) and mortality ( 20 % vs 9 % , P<.001 ) . CONCLUSIONS Approximately 62 % of patients with necrotizing pancreatitis can be treated without an intervention and with low mortality . In patients with infected necrosis , delayed intervention and catheter drainage as first treatment improves outcome In 39 patients with severe attacks of acute pancreatitis , a longitudinal study was done with respect to the influence of peritoneal lavage on objective prognostic signs ( WBC , blood-glucose , scrum-calcium , hematocrit , serum-creatininc , arterial pO2 , base deficit ) ; amylasc activities in peritoneal fluid , serum , and urine ; serum-hemoglobin , serum-Na , serum-K , and plasma-insulin . In addition to st and ard care in the ICU , half of the patients ( N = 19 ) were r and omly treated with peritoneal lavage . Peritoneal lavage did not influence overall mortality ( 13 % ) , incidence of major complications ( 36 % ) , or hospital stay ( 23 ± 7 days ) . None of the prognostic signs was significantly influenced by lavage . Amylase concentration in peritoneal fluid was significantly reduced in the lavaged group after 6 hours compared to 24 hours in controls . Serum and urinary amylasc decreased 12 hours earlier in the lavaged group , indicating an efficiency of the lavage procedure per-se . Still , this study did not reveal any beneficial clinical effects of peritoneal lavage in acute pancreatitis Mixed treatment comparison ( MTC ) meta- analysis is a generalization of st and ard pairwise meta- analysis for A vs B trials , to data structures that include , for example , A vs B , B vs C , and A vs C trials . There are two roles for MTC : one is to strengthen inference concerning the relative efficacy of two treatments , by including both ' direct ' and ' indirect ' comparisons . The other is to facilitate simultaneous inference regarding all treatments , in order for example to select the best treatment . In this paper , we present a range of Bayesian hierarchical models using the Markov chain Monte Carlo software WinBUGS . These are multivariate r and om effects models that allow for variation in true treatment effects across trials . We consider models where the between-trials variance is homogeneous across treatment comparisons as well as heterogeneous variance models . We also compare models with fixed ( unconstrained ) baseline study effects with models with r and om baselines drawn from a common distribution . These models are applied to an illustrative data set and posterior parameter distributions are compared . We discuss model critique and model selection , illustrating the role of Bayesian deviance analysis , and node-based model criticism . The assumptions underlying the MTC models and their parameterization are also discussed Background The initial treatment of acute necrotizing pancreatitis is conservative . Intervention is indicated in patients with ( suspected ) infected necrotizing pancreatitis . In the Netherl and s , the st and ard intervention is necrosectomy by laparotomy followed by continuous postoperative lavage ( CPL ) . In recent years several minimally invasive strategies have been introduced . So far , these strategies have never been compared in a r and omised controlled trial . The PANTER study ( PAncreatitis , Necrosectomy versus sTEp up appRoach ) was conceived to yield the evidence needed for a considered policy decision . Methods / design 88 patients with ( suspected ) infected necrotizing pancreatitis will be r and omly allocated to either group A ) minimally invasive ' step-up approach ' starting with drainage followed , if necessary , by videoscopic assisted retroperitoneal debridement ( VARD ) or group B ) maximal necrosectomy by laparotomy . Both procedures are followed by CPL .  Patients will be recruited from 20 hospitals , including all Dutch university medical centres , over a 3-year period . The primary endpoint is the proportion of patients suffering from postoperative major morbidity and mortality . Secondary endpoints are complications , new onset sepsis , length of hospital and intensive care stay , quality of life and total ( direct and indirect ) costs . To demonstrate that the ' step-up approach ' can reduce the major morbidity and mortality rate from 45 to 16 % , with 80 % power at 5 % alpha , a total sample size of 88 patients was calculated . Discussion The PANTER- study is a r and omised controlled trial that will provide evidence on the merits of a minimally invasive ' step-up approach ' in patients with ( suspected ) infected necrotizing pancreatitis Background Development of abdominal compartment syndrome ( ACS ) in patients with severe acute pancreatitis ( SAP ) has a strong impact on the course of disease . Number of patients with this complication increases during the years due more aggressive fluid resuscitation , much bigger proportion of patients who is treated conservatively or by minimal invasive approach , and efforts to delay open surgery . There have not been st and ard recommendations for a surgical or some other interventional treatment of patients who develop ACS during the SAP . The aim of DECOMPRESS study was to compare decompresive laparotomy with temporary abdominal closure and percutaneus puncture with placement of abdominal catheter in these patients . Methods One hundred patients with ACS will be r and omly allocated to two groups : I ) decompresive laparotomy with temporary abdominal closure or II ) percutaneus puncture with placement of abdominal catheter .  Patients will be recruited from five hospitals in Bel grade during two years period . The primary endpoint is the mortality rate within hospitalization . Secondary endpoints are time interval between intervention and resolving of organ failure and multi organ dysfunction syndrome , incidence of infectious complications and duration of hospital and ICU stay . A total sample size of 100 patients was calculated to demonstrate that decompresive laparotomy with temporary abdominal closure can reduce mortality rate from 60 % to 40 % with 80 % power at 5 % alfa . Conclusion DECOMPRESS study is design ed to reveal a reduction in mortality and major morbidity by using decompresive laparotomy with temporary abdominal closure in comparison with percutaneus puncture with placement of abdominal catheter in patients with ACS during SAP.Trial registration Clinical Trials.gov Identifier : Twenty-one patients with acute fulminant alcoholic pancreatitis were r and omly allocated to either pancreatic resection group ( 11 patients ) or nonoperative peritoneal lavage group ( 10 patients ) . Only patients under 50 years were included in the study to minimize the role of other severe disease . These patients represented the most severe cases of acute pancreatitis at our Department , constituting only 2 % of all patients with acute pancreatitis during this period . The diagnosis was based on clinical symptoms and on signs indicating severely impaired systemic organ functions . All patients underwent contrast-enhanced computed tomography ( CT ) , which showed contrast enhancement below 30 Hounsfield units . In the operated cases , the diagnosis of necrotizing pancreatitis was verified histologically . All patients with conservative treatment had dark brown fluid at peritoneal puncture . There was a difference ( nonsignificant ) in mortality ( 3/11 and 1/10 , respectively ) , complication rate , or in the need of reoperations between the groups . Nonoperative peritoneal lavage was followed with shorter treatment at the intensive care unit ( 16.2 versus 25.9 days , respectively , ) . The hospital stay also was significantly shorter in the nonoperative group ( 44.3 versus 56.1 days ) . The results indicate that intensive conservative treatment is justified as an initial therapy even in the most severe cases of acute pancreatitis Summary Fifty-five patients with severe acute pancreatitis were treated with 
    Output:
    
AUTHORS ' CONCLUSIONS Low to very low quality evidence suggested that the minimally invasive step-up approach result ed in fewer adverse events , serious adverse events , less organ failure , and lower costs compared to open necrosectomy .
Very low quality evidence suggested that the endoscopic minimally invasive step-up approach result ed in fewer adverse events than the video-assisted minimally invasive step-up approach but increased the number of procedures required for treatment .
There is currently no evidence to suggest that early open necrosectomy is superior or inferior to peritoneal lavage or delayed open necrosectomy .