***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: BACKGROUND Continuous veno-venous haemofiltration is increasingly used to treat acute renal failure in critically ill patients , but a clear definition of an adequate treatment dose has not been established . We undertook a prospect i ve r and omised study of the impact different ultrafiltration doses in continuous renal replacement therapy on survival . METHODS We enrolled 425 patients , with a mean age of 61 years , in intensive care who had acute renal failure . Patients were r and omly assigned ultrafiltration at 20 mL h(-1 ) kg(-1 ) ( group 1 , n=146 ) , 35 mL h(-1 ) kg(-1 ) ( group 2 , n=139 ) , or 45 mL h(-1 ) kg(-1 ) ( group 3 , n=140 ) . The primary endpoint was survival at 15 days after stopping haemofiltration . We also assessed recovery of renal function and frequency of complications during treatment . Analysis was by intention to treat . RESULTS Survival in group 1 was significantly lower than in groups 2 ( p=0.0007 ) and 3 ( p=0.0013 ) . Survival in groups 2 and 3 did not differ significantly ( p=0.87 ) . Adjustment for possible confounding factors did not change the pattern of differences among the groups . Survivors in all groups had lower concentrations of blood urea nitrogen before continuous haemofiltration was started than non-survivors . 95 % , 92 % , and 90 % of survivors in groups 1 , 2 , and 3 , respectively , had full recovery of renal function . The frequency of complications was similarly low in all groups . INTERPRETATION Mortality among these critically ill patients was high , but increase in the rate of ultrafiltration improved survival significantly . We recommend that ultrafiltration should be prescribed according to patient 's bodyweight and should reach at least 35 mL h(-1 ) kg(-1 ) Abstract Systemic inflammatory response syndrome ( SIRS ) prevention is key to severe acute pancreatitis ( SAP ) treatment and the assessment of high-volume hemofiltration ( HVHF ) for treating SAP accompanying multiple organ dysfunction syndromes . In this prospect i ve controlled study , 40 SAP patients were divided into 2 groups : control ( n = 22 , treated with fasting , decompression , and intravenous somatostatin ) and HVHF ( n = 18 , HVHF administration in addition to the treatment in the control group ) groups ; and were assessed for serum and urine amylase , WBC , C-reactive protein ( CRP ) , and hepatic and renal functions . Vital signs and abdominal symptoms were recorded , and complications and mortality were analyzed . APACHE II scores in the HVHF group were significantly lower than in the control group at 3 and 7 days ( 6.3 ± 1.7 vs 9.2 ± 2.1 and 3.3 ± 0.8 vs 6.2 ± 1.7 , respectively ) . Compared with controls , serum , and urine amylase , WBC , CRP , and organ functions significantly improved after HVHF treatment . Meanwhile , mortality ( 16.7 % vs 31.8 % ) and complication ( 11.1 % vs 40.9 % ) rates were significantly reduced . The other clinical parameters were significantly ameliorated by HVHF . HVHF rapidly reduces abdominal symptoms and improves prognosis , reducing mortality in SAP patients ; and is likely through systemic inflammatory response syndrome attenuation in the early disease stage BACKGROUND AND OBJECTIVES The evidence for high-volume hemofiltration plus hemoperfusion ( HVHF&HP ) for hyperlipidemic severe acute pancreatitis ( HL-SAP ) is anecdotal . The purpose of our study was to evaluate the efficacy of HVHF&HP for HL-SAP in a prospect i ve controlled study . DESIGN AND SETTING Prospect i ve controlled pilot study between May 2010 and May 2013 in a hospital intensive care unit . PATIENTS AND METHODS HL-SAP patients chose conventional treatment alone (  the control group ) or conventional treatment combined with the experimental protocol  ( the HVHF&HP group ) and were prospect ively followed in our hospital . APACHE II score , SOFA score , ICU and hospital stay duration , and serum biomarkers were considered endpoints . RESULTS Ten HL-SAP patients accepted conventional treatment alone  ( the control group ) and 10 patients underwent HVHF&HP combined with conventional treatment ( the HVHF&HP group ) . The APACHE II score , SOFA score , systolic blood pressure , diastolic blood pressure , heart rate , serum amylase , and serum creatinine were significantly reduced after the HVHF&HP treatment . The changes in these variables were significantly different between the HVHF&HP and control group at 48 hours after the initiation of treatment . Patients in the HVHF&HP group had a significantly shorter ICU stay ( P=.015 ) . The reduction in serum triglyceride and cholesterol in the HVHF&HP group after 2 , 6 , 12 , 24 , and 48 hours was greater than the control group . All of the tested serum cytokines were significantly decreased after HVHF&HP treatment ( P<.05 ) . However , in patients who underwent conventional treatment alone , there was no significant change in the serum cytokines . CONCLUSION This study suggests that the addition of HVHF&HP to conventional treatment for HL-SAP patients may be superior to conventional treatment alone for the improvement of serum biomarkers and clinical outcomes Objective : Our aim was to study the therapeutic effects and the mechanism of combination of hemofiltration ( HF ) and peritoneal dialysis ( PD ) in the treatment of severe acute pancreatitis ( SAP ) . Methods : Fifty-one cases of SAP were r and omly divided into the  HF+PD group ( treated group , 36 patients ) and the non-HF+PD group ( control group , 15 patients ) . Both groups were treated by the same traditional methods . The relief time of abdominal pain and abdominal distension , computed tomographic scores , acute physiology and chronic health enquiry II scores , length of stay , cost of hospitalization , operability , and recovery rate of the 2 groups were compared . The concentration of tumor necrosis factor-&agr ; , IL-6 , and IL-8 in serum and ascites volumes was determined before and after treatment . Results : The mean time of abdominal pain relief , amelioration of abdominal distension , decrease of computed tomographic scores , acute physiology and chronic health enquiry II scores , the mean length of stay , and cost of hospitalization of the treated group were significantly shorter or less than those of the control group . The aforementioned inflammatory cytokines , detected at the end of 1 day and 2 days after HF+PD treatment , were decreased significantly compared with those observed in pretherapy and the control group . Conclusions : Inflammatory cytokines , which overproduced in SAP , can be eliminated effectively from the blood and the ascites by HF+PD treatment A potential application of the continuous renal replacement therapies is the extracorporeal removal of inflammatory mediators in septic patients . Cytokine elimination with continuous renal replacement therapies has been demonstrated in several clinical studies , but so far without important effects on their serum concentrations . Improved knowledge of the cytokine removal mechanisms could lead to the development of more efficient treatment strategies . In the present study , 15 patients with septic shock and acute renal failure were observed during the first 24 h of treatment with continuous venovenous hemofiltration ( CVVH ) with an AN69 membrane .  After 12 h , the hemofilter was replaced and the blood flow rate ( QB ) was switched from 100 ml/min to 200 ml/min or vice versa . Pre- and postfilter plasma and ultrafiltrate concentrations of selected inflammatory and anti-inflammatory cytokines were measured at several time points allowing the calculation of a mass balance . Cytokine removal was highest 1 h after the start of CVVH and after the change of the membrane ( ranging from 25 to 43 % of the prefilter amount ) , corresponding with a significant fall in the serum concentration of all cytokines . The inhibitors of inflammation were removed to the same extent as the inflammatory cytokines . Adsorption to the AN69 membrane appeared to be the main clearance mechanism , being most pronounced immediately after installation of a new membrane and decreasing steadily thereafter , indicating rapid saturation of the membrane . A QB of 200 ml/min was associated with a 75 % increase of the ultrafiltration rate and a significantly higher convective elimination and membrane adsorption than at a QB of 100 ml/min . The results indicate that optimal cytokine removal with CVVH with an AN69 membrane could be achieved with a combination of a high QB/ultrafiltration rate and frequent membrane changes AIM To investigate whether continuous veno-venous hemofiltration ( CVVH ) in different filtration rate to eliminate cytokines would result in different efficiency in acute pancreatitis , whether the saturation time of filter membrane was related to different filtration rate , and whether the onset time of CVVH could influence the survival of acute pancreatitis . METHODS Thirty-seven patients were classified into four groups r and omly . Group 1 underwent low-volume CVVH within 48 h of the onset of abdominal pain ( early CVVH , n = 9 ) . Group 2 received low-volume CVVH after 96 h of the onset of abdominal pain ( late CVVH , n = 10 ) . Group 3 underwent high-volume CVVH within 48 h of the onset of abdominal pain ( early CVVH , n = 9 ) . Group 4 received high-volume CVVH after 96 h of the onset of abdominal pain ( late CVVH , n = 9 ) . CVVH was sustained for at least 72 h. Blood was taken before hemofiltration , and ultrafiltrate was collected at the start of CVVH and every 12 h during CVVH period for the purpose of measuring the concentrations of TNF-alpha , IL-1beta and IL-6 . The concentrations of TNF-alpha , IL-1beta and IL-6 were measured by swine-specific ELISA . The Solartron 1 255 B frequency response analyzer ( British ) was used to observe the resistance of filter membrane . RESULTS The survival rate had a significant difference ( 94.44 % vs 68.42 % , P<0.01 ) high-volume and low-volume CVVH patients . The survival rate had also a significant difference ( 88.89 % vs 73.68 % , P<0.05 ) between early and late CVVH patients . The hemodynamic deterioration ( MAP , HR , CVP ) was less severe in groups 4 and 1 than that in group 2 , and in group 3 than in group 4 . The adsorptive saturation time of filters membranes was 120 - 180 min if the filtration rate was 1 000 - 4 000 mL/h . After the first , second and third new hemofilters were changed , serum TNF-alpha concentrations had a negative correlation with resistance ( r : -0.91 , -0.89 , and -0.86 , respectively in group 1 ; -0.89 , -0.85 , and -0.76 , respectively in group 2 ; -0.88 , -0.92 , and -0.82 , respectively in group 3 ; -0.84 , -0.87 , and -0.79 , respectively in group 4 ) . The decreasing extent of TNF-alpha , IL-1beta and IL-6 was significantly different between group 3 and group 1 ( TNF-alpha P<0.05 , IL-1beta P<0.05 , IL-6 P<0.01 ) , between group 4 and group 2 ( TNF-alpha P<0.05 , IL-1beta P<0.05 , IL-6 P<0.01 ) , between group 1 and group 2 ( TNF-alpha P<0.05 , IL-1beta P<0.05 , IL-6 P<0.05 ) , and between group 3 and group 4 ( TNF-alpha P<0.01 , IL-1beta P<0.01 , IL-6 P<0.05 ) , respectively during CVVH period . The decreasing extent of TNF-alpha and IL-1beta was also significantly different between survival patients and dead patients ( TNF-alpha P<0.05 , IL-1beta P<0.05 ) . In survival patients , serum concentration of TNF-alpha and IL-1beta decreased more significantly than that in dead patients . CONCLUSION High-volume and early CVVH improve hemodynamic deterioration and survival in acute pancreatitis patients . High-volume CVVH can eliminate cytokines more efficiently than low-volume CVVH . The survival rate is related to the decrease extent of TNF-alpha and IL-1beta . The adsorptive saturation time of filter membranes are different under different filtration rate condition . The filter should be changed timely once filter membrane adsorption is saturated Background Convective dialysis modalities ( haemofiltration ( HF ) , haemodiafiltration ( HDF ) , and acetate-free biofiltration ( AFB ) ) removed excess body fluid across the dialysis membrane with positive pressure and accumulated middle- and larger-size accumulated solutes more efficiently than haemodialysis ( HD ) . This increased larger solute removal combined with use of ultra-pure dialysis fluid in convective dial 
    Output:
    
It is unclear whether CVVH has any effect on mortality or complications in patients with severe acute pancreatitis .
It is also unclear whether high-volume CVVH is superior , equivalent or inferior to st and ard CVVH in patients with severe acute pancreatitis