***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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    ***EXAMPLES*** 
    Input: In the nutritional management of digestive disorders , it is important to know the relative secretory and metabolic responses to enteral and parenteral feeding .  Twenty-seven healthy volunteers were studied while receiving either oral drinks or duodenal infusions of a complex formula diet , duodenal or intravenous infusions of elemental ( protein as free amino acids , low fat ) formulae , or saline . Pancreaticobiliary secretory responses were measured by nasoduodenal polyethylene glycol perfusion and aspiration , while monitoring blood hormone and nutrient levels . Diets were matched for protein ( 1.5 g x kg(-1 ) x d(-1 ) ) and energy ( 40 kcal x kg(-1 ) x d(-1 ) ) . Compared with placebo , all oroenteral diets stimulated amylase , lipase , trypsin , and bile acid secretion and increased plasma concentrations of gastrin and cholecystokinin , whereas intravenous feeding did not . The complex formula produced a similar response whether given as drinks or duodenal infusions . Changing the duodenal formula to elemental reduced enzyme secretion by 50 % , independently of CCK . Higher increases in plasma insulin , glucose , and amino acids were noted with intravenous feeding . Delivering food directly to the intestine by a feeding tube does not reduce pancreaticobiliary secretion . Enteral " elemental " formulae diminish , but only intravenous feeding avoids pancreatic stimulation . Intravenous administration impairs metabolic clearance Studies in humans have shown that pancreatic enzyme secretion is reduced during acute pancreatitis . It is not known , however , whether the reduction is due to impaired synthesis or disruption of the secretory pathway . The rate of secretion and turnover of trypsin was measured in 12 patients with acute pancreatitis of variable etiology and severity ( median Ranson 's score 2.5 , range 0 - 5 , 4 with severe necrotizing disease ) and eight healthy volunteers by  4-h primed/continuous intravenous infusions of 1-(13)C-labeled l-leucine , and collection of pancreatic secretions by duodenal perfusion and sampling .  Trypsin secretion was reduced from 476 + /- 73 to 153 + /- 60 U/h ( means + /- SE , P = 0.005 ) in acute pancreatitis , with the greatest reductions being observed in patients with necrotizing disease ( 32 + /- 7 U/h , P = 0.003 ) . The time for newly labeled trypsin to first appear in digestive juice was not , however , delayed in pancreatitis patients ( 87.2 + /- 11.1 vs. 94.7 + /- 4.9 min ) ; on the contrary , there was an early appearance of newly labeled trypsin at 30 min in patients with severe necrotizing pancreatitis ( P < 0.05 ) . Calculated zymogen pool turnover was unchanged , but pool size was decreased ( P = 0.01 ) . Despite low rates of luminal secretion , trypsin continues to be synthesized in patients with acute pancreatitis . Our findings could be explained by post-Golgi leakage of enzymes from acinar cells or by loss of synthetic function in some cells with preservation in others BACKGROUND : After 50 yr in which nasoenteric feeding was considered contraindicated in acute pancreatitis ( AP ) , several clinical studies have shown that early nasojejunal ( NJ ) feeding can be achieved in most patients . A pilot study of early nasogastric ( NG ) feeding in patients with objective ly grade d severe AP proved that this approach was also feasible . A r and omized study comparing NG versus NJ feeding has been performed . METHODS : A total of 50 consecutive patients with objective ly grade d severe AP were r and omized to receive either NG or NJ feeding via a fine bore feeding tube . The end points were markers of the acute phase response APACHE II scores and C-reactive protein ( CRP ) measurements , and pain patterns by visual analogue score ( VAS ) and analgesic requirements . Complications were monitored and comparisons made of both total hospital and intensive-care stays . RESULTS : A total of 27 patients were r and omized to NG feeding and 23 to NJ . One of those in the NJ group had a false diagnosis , thereby reducing the number to 22 . Demographics were similar between the groups and no significant differences were found between the groups in APACHE II score , CRP measurement , VAS , or analgesic requirement . Clinical differences between the two groups were not significant . Overall mortality was 24.5 % with five deaths in the NG group and seven in the NJ group . CONCLUSIONS : The simpler , cheaper , and more easily used NG feeding is as good as NJ feeding in patients with objective ly grade d severe AP . This appears to be a useful and practical therapeutic approach to enteral feeding in the early management of patients with severe AP Objective : To compare the efficacy and safety of early , nasogastric enteral nutrition ( EN ) with total parenteral nutrition ( TPN ) in patients with predicted severe acute pancreatitis ( SAP ) . Summary Background Data : In SAP , the magnitude of the inflammatory response as well as increased intestinal permeability correlates with outcome . Enteral feeding has been suggested superior to parenteral feeding due to a proposed beneficial effect on the gut barrier . Methods : Fifty patients who met the inclusion criteria were r and omized to TPN or EN groups . The nutritional regimen was started within 24 hours from admission and EN was provided through a nasogastric tube . The observation period was 10 days . Intestinal permeability was measured by excretion of polyethylene glycol ( PEG ) and concentrations of antiendotoxin core antibodies ( Endocab ) . Interleukins (IL)-6 IL-8 , and C-reactive protein ( CRP ) were used as markers of the systemic inflammatory response . Morbidity and feasibility of the nutritional route were evaluated by the frequency of complications , gastrointestinal symptoms , and abdominal pain . Results : PEG , Endocab , CRP , IL-6 , APACHE II score , severity according to the Atlanta classification ( 22 patients ) , and gastrointestinal symptoms or abdominal pain did not significantly differ between the groups . The incidence of hyperglycemia was significantly higher in  TPN patients ( 21 of 26 vs. 7 of 23 ; P < 0.001 ) . Total complications ( 25 vs. 52 ; P = 0.04 ) and pulmonary complications ( 10 vs. 21 ; P = 0.04 ) were significantly more frequent in EN patients , although complications were diagnosed dominantly within the first 3 days . Conclusion : In predicted SAP , nasogastric early EN was feasible and result ed in better control of blood glucose levels , although the overall early complication rate was higher in the EN group . No beneficial effects on intestinal permeability or the inflammatory response were seen by EN treatment Background : Infectious complications are the main cause of late death in patients with acute pancreatitis . Routine prophylactic antibiotic use following a severe attack has been proposed but remains controversial . On the other h and , nutritional support has recently yielded promising clinical results . The aim of study was to compare enteral vs. parenteral feeding for prevention of infectious complications in patients with predicted severe acute pancreatitis . Methods : We screened 466 consecutive patients with acute pancreatitis . A total of 70 patients with objective ly grade d severe acute pancreatitis were r and omly allocated to receive either total enteral nutrition ( TEN ) or total parenteral nutrition ( TPN ) , within 72 h of onset of symptoms . Baseline characteristics were well matched in the two groups . Results : The incidence of pancreatic infectious complications ( infected pancreatic necrosis , pancreatic abscess ) was significantly lower in the enterally fed group ( 7 vs. 16 , p = 0.02 ) . In the TEN group , 7 patients developed multiple organ failure whereas 17 parenterally fed patients developed multiple organ failure ( p = 0.02 ) . Overall mortality was 20 % with two deaths in the TEN group and twelve in the TPN group ( p < 0.01 ) . Conclusion : Early TEN could be used as prophylactic therapy for infected pancreatic necrosis since it significantly decreased the incidence of pancreatic infectious complications as well as the frequency of multiple organ failure and mortality In recent years , a number of articles have been published on the treatment of  acute pancreatitis  in experimental models and most of them were published about animals with mild disease . However , it is difficult to translate these results into clinical practice . For example , infliximab , a monoclonal TNF antibody , was experimentally tested in rats and it was able to significantly reduce the pathologic score and serum amylase activity , and also alleviate alveolar edema and acute respiratory distress syndrome ; no studies are available in clinical human acute pancreatitis . Another substance , such as interleukin 10 , was efficacious in decreasing the severity and mortality of lethal pancreatitis in rats , but seems to have no effect on human severe acute pancreatitis . Thus , the main problem in acute pancreatitis , especially in the severe form of the disease , is the difficulty of planning clinical studies capable of giving hard statistically significant answers regarding the benefits of the various proposed therapeutic agents previously tested in experimental setting s. According to the pathophysiology of acute pancreatitis , we may re-evaluate the efficacy of the drugs already available , such as gabexate mesilate , lexipafant and somatostatin which should be probably administered in a different manner . Of course , also in this case , we need large studies to test this hypothesis . Another great problem is prevention of the infection of pancreatic necrosis . A r and omized study has been published to test the hypothesis that probiotics and specific fibres used as supplements in early enteral nutrition may be effective in reducing pancreatic sepsis and the number of surgical interventions . A study named PROPATRIA ( Probiotic Prophylaxis in Patients with Predicted Severe Acute Pancreatitis ) has been planned to give a more robust confirmation to the previous study . Furthermore , the open question of the prevention of the fungal infection of necrosis is still being debated . Finally , the prevention of pain relapse after oral feeding in patients with mild or severe acute pancreatitis should be explored . Even if some studies exist on this issue , the question of optimal treatment is still unanswered . As in other diseases , obtaining results when treating patients with acute pancreatitis is difficult and will take continuous small steps Aims : The aim of this prospect i ve study was to assess pancreatic exocrine function in patients recovering from a first attack of acute pancreatitis , and to evaluate its relationship to severity of attack , extent of pancreatic necrosis and severity of pancreatic endocrine insufficiency . Methods : Between December 2000 and November 2001 , 23 patients were prospect ively evaluated .  Pancreatic exocrine function was measured by the  faecal elastase-1 test  and insufficiency was classified as moderately impaired or severely impaired . Pancreatic necrosis was determined by contrast-enhanced CT scan , and its extent was categorised according to Balthazar ’s classification . The severity of pancreatic endocrine insufficiency was categorised according to insulin dependence . Attacks were classified as mild ( n = 16 ) or severe ( n = 7 ) according to the Atlanta criteria . Results : Pancreatic exocrine insufficiency was significantly more frequent in patients recovering from severe attacks than mild ( n = 6 , 86 % vs. n = 2 , 13 % ; p = 0.002 ) , and in those who developed pancreatic necrosis or pseudocyst than those who did not ( 6 of 7 patients vs. 2 of 16 patients , and 5 of 5 patients vs. 3 of 18 patients respectively ; p = 0.002 ) . The development of exocrine insufficiency correlated strongly with the extent of pancreatic necrosis ( r = –0.754 , p < 0.001 ) , and the severity of pancreatic endocrine insufficiency ( n = 4 , r = –0.453 , p = 0.03 ) . Conclusion : Pancreatic exocrine insufficiency is a common occurrence in patients recovering from severe acute pancreatitis , and its severity correlates with the extent of pancreatic necrosis and the severity of concomitant pancreatic endocrine insufficiency Summary Background . Severe acute pancreatitis may be protracted and some form of nutritional support is frequently required to maintain the patient ’s nutritional status . Recent work has suggested that enteral feeding via a jejunal route of delivery may reduce the magnitude of the inflammatory response . Insertion of nasojejunal ( NJ ) tubes in the patient with severe acute pancreatitis involves both delay and inconvenience . We undertook a prospect i ve , feasibility study to assess the safety and practicability of nasogastric ( NG ) feeding in patients with severe acute pancreatitis . Patients and Methods . Twenty-six patients with objective evidence of severe acute pancreatitis received nasogastric feeding  within 48 h of admission to our unit . Results . Etiology was identified as cholelithiasis ( 18 patients ) , ethanol ( 5 ) , and miscellaneous ( 3 ) . The median Glasgow score was 4 ( range 2–7 ) , APACHE II score 10 ( 4–28 ) , and C-reactive protein concentration 286 mg/L (  
    Output:
    
Nasogastric feeding appears safe and well tolerated in patients with predicted severe acute pancreatitis .