***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 & AIMS Adverse consequences may be experienced by critically ill patients who are underfed during their stay in the intensive care unit . The objective of this study is to determine the prevalence of iatrogenic underfeeding ( receiving < 80 % of prescribed energy requirements ) and the variation of these rates in different geographic regions of the world and in different nutritionally ' at-risk ' patient population s. METHODS This was a prospect i ve , multi-institutional study in 201 units from 26 countries . We included 3390 mechanically ventilated patients who remained in the unit and received artificial nutrition for at least 96 h. We report time to start of enteral nutrition and % nutrition received in various geographic regions of the world and we focus on subgroups of ' high risk ' patients ( those with > 7 days of mechanical ventilation , body mass index of < 25 or ≥35 , and those with a Nutrition Risk In the Critically ill ( NUTRIC ) score of ≥5 ) . We report rates of novel enteral nutrition delivery techniques and supplemental parenteral nutrition in these high risk patients . RESULTS On average , enteral feedings were started 38.8 h ( st and ard deviation : 39.6 ) after admission , patients received 61.2 % of calories and 57.6 % of protein prescribed , and 74.0 % of patients failed to meet the quality metric of receiving at least 80 % of energy targets . There were significant differences in nutrition outcomes across different geographic regions . There were no clinical ly important differences in nutrition outcomes or rates of iatrogenic underfeeding in patients in different BMI groups nor by NUTRIC score . Of all at-risk patients , 14 % were ever prescribed volume-based feeds , and 15 % of patients ever received supplemental parenteral nutrition . CONCLUSIONS Worldwide , the majority of critically ill patients , including high nutritional risk patients , fail to receive adequate nutritional intake . There is low uptake of strategies design ed to optimize nutrition delivery in these patients BACKGROUND The purpose of this study was to determine the effects of early postoperative tube feeding on outcomes of liver transplant recipients . METHODS Fifty transplant patients were r and omized prospect ively to receive enteral formula via nasointestinal feeding tubes ( tube-feeding [ TF ] group ) or maintenance i.v . fluid until oral diets were initiated ( control group ) . Thirty-one patients completed the study .  Resting energy expenditure , nitrogen balance , and grip strength were measured on days 2 , 4 , 7 , and 12 after liver transplantation . Calorie and protein intakes were calculated for 12 days posttransplant . RESULTS Tube feeding was tolerated in the TF group ( n = 14 ) . The TF patients had greater cumulative 12-day nutrient intakes ( 22,464 + /- 3554 kcal , 927 + /- 122 g protein ) than did the control patients ( 15,474 + /- 5265 kcal , 637 + /- 248 g protein ) ( p < .002 ) . Nitrogen balance was better in the TF group on posttransplant day 4 than in the control group ( p < .03 ) . There was a rise in the overall mean resting energy expenditure in the first two posttransplant weeks from 1487 + /- 338 to 1990 + /- 367 kcal ( p = .0002 ) . Viral infections occurred in 17.7 % of control patients compared with 0 % of TF patients ( p = .05 ) . Although other infections tended to occur more frequently in the control group vs the TF group ( bacterial , 29.4 % vs 14.3 % ; overall infections , 47.1 % vs 21.4 % ) , these differences were not statistically significant . Early posttransplant tube feeding did not influence hospitalization costs , hours on the ventilator , lengths of stay in the intensive care unit and hospital , rehospitalizations , or rejection during the first 21 posttransplant days . CONCLUSIONS Early posttransplant tube feeding was tolerated and promoted improvements in some outcomes and should be considered for all liver transplant patients Objective : Critically ill patients are at high risk of malnutrition . Insufficient nutritional support still remains a widespread problem despite guidelines . The aim of this study was to measure the clinical impact of a two-step interdisciplinary quality nutrition program . Design : Prospect i ve interventional study over three periods ( A , baseline ; B and C , intervention periods ) . Setting : Mixed intensive care unit within a university hospital . Patients : Five hundred seventy-two patients ( age 59 ± 17 yrs ) requiring > 72 hrs of intensive care unit treatment . Intervention : Two-step quality program : 1 ) bottom-up implementation of feeding guideline ; and 2 ) additional presence of an intensive care unit dietitian . The nutrition protocol was based on the European guidelines . Measurements and Main Results : Anthropometric data , intensive care unit severity scores , energy delivery , and cumulated energy balance ( daily , day 7 , and discharge ) , feeding route ( enteral , parenteral , combined , none – oral ) , length of intensive care unit and hospital stay , and mortality were collected . Altogether 5800 intensive care unit days were analyzed . Patients in period A were healthier with lower Simplified Acute Physiologic Scale and proportion of “ rapidly fatal ” McCabe scores . Energy delivery and balance increased gradually : impact was particularly marked on cumulated energy deficit on day 7 which improved from −5870 kcal to −3950 kcal ( p < .001 ) . Feeding technique changed significantly with progressive increase of days with nutrition therapy ( A : 59 % days , B : 69 % , C : 71 % , p < .001 ) , use of enteral nutrition increased from A to B ( stable in C ) , and days on combined and parenteral nutrition increased progressively . Oral energy intakes were low ( mean : 385 kcal*day−1 , 6 kcal*kg−1*day −1 ) . Hospital mortality increased with severity of condition in periods B and C. Conclusion : A bottom-up protocol improved nutritional support . The presence of the intensive care unit dietitian provided significant additional progression , which were related to early introduction and route of feeding , and which achieved overall better early energy balance This document represents the first collaboration between 2 organizations — the American Society for Parenteral and Enteral Nutrition and the Society of Critical Care Medicine — to describe best practice s in nutrition therapy in critically ill children . The target of these guidelines is intended to be the pediatric critically ill patient ( > 1 month and 2–3 days in a PICU admitting medical , surgical , and cardiac patients . In total , 2032 citations were scanned for relevance . The PubMed / MEDLINE search result ed in 960 citations for clinical trials and 925 citations for cohort studies . The EMBASE search for clinical trials culled 1661 citations . In total , the search for clinical trials yielded 1107 citations , whereas the cohort search yielded 925 . After careful review , 16 r and omized controlled trials and 37 cohort studies appeared to answer 1 of the 8 preidentified question groups for this guideline . We used the GRADE criteria ( Grading of Recommendations , Assessment , BACKGROUND Despite extensive use of enteral ( EN ) and parenteral nutrition ( PN ) in intensive care unit ( ICU ) population s for 4 decades , evidence to support their efficacy is extremely limited . METHODS A prospect i ve r and omized trial was conducted evaluate the impact on outcomes of intensive medical nutrition therapy ( IMNT ; provision of > 75 % of estimated energy and protein needs per day via EN and adequate oral diet ) from diagnosis of acute lung injury ( ALI ) to hospital discharge compared with st and ard nutrition support care ( SNSC ; st and ard EN and ad lib feeding ) . The primary outcome was infections ; secondary outcomes included number of days on mechanical ventilation , in the ICU , and in the hospital and mortality . RESULTS Overall , 78 patients ( 40 IMNT and 38 SNSC ) were recruited . No significant differences between groups for age , body mass index , disease severity , white blood cell count , glucose , C-reactive protein , energy or protein needs occurred . The IMNT group received significantly higher percentage of estimated energy ( 84.7 % vs 55.4 % , P < .0001 ) and protein needs ( 76.1 vs 54.4 % , P < .0001 ) per day compared with SNSC . No differences occurred in length of mechanical ventilation , hospital or ICU stay , or infections . The trial was stopped early because of significantly greater hospital mortality in IMNT vs SNSC ( 40 % vs 16 % , P = .02 ) . Cox proportional hazards models indicated the hazard of death in the IMNT group was 5.67 times higher ( P = .001 ) than in the SNSC group . CONCLUSIONS Provision of IMNT from ALI diagnosis to hospital discharge increases mortality Background Early start of enteral feeding is an established treatment strategy in intubated patients in intensive care since it reduces invasive bacterial infections and length of hospital stay . There is equipoise whether early enteral feeding is also beneficial in non-intubated patients with cerebral malaria in re source poor setting s. We hypothesized that the risk of aspiration pneumonia might outweigh the potential benefits of earlier recovery and prevention of hypoglycaemia . Method and Findings A r and omized trial of early ( day of admission ) versus late ( after 60 hours in adults or 36 hours in children ) start of enteral feeding was undertaken in patients with cerebral malaria in Chittagong , Bangladesh from May 2008 to August 2009 . The primary outcome measures were incidence of aspiration pneumonia , hypoglycaemia and coma recovery time . The trial was terminated after inclusion of 56 patients because of a high incidence of aspiration pneumonia in the early feeding group ( 9/27 ( 33 % ) ) , compared to the late feeding group ( 0/29 ( 0 % ) ) , p = 0.001 ) . One patient in the late feeding group , and none in the early group , had hypoglycaemia during admission . There was no significant difference in overall mortality ( 9/27 ( 33 % ) vs 6/29 ( 21 % ) , p = 0.370 ) , but mortality was 5/9 ( 56 % ) in patients with aspiration pneumonia . Conclusions In conclusion , early start of enteral feeding is detrimental in non-intubated patients with cerebral malaria in many re source -poor setting s. Evidence gathered in re source rich setting s is not necessarily transferable to re source -poor setting s. Trial Registration Controlled-Trials.com IS RCT The critical care community still has mixed feelings when considering the optimal nutrition of intensive care unit ( ICU ) patients , which is underst and able as r and omized controlled trials have not been very helpful in improving clinical practice . There have been no r and omized controlled trials ( RCTs ) to contribute to the discussion , especially concerning the role of enterally fed protein in optimal critical care . Recent studies on the route of feeding have shown that enteral nutrition ( EN ) is not necessarily superior to parenteral nutrition ( PN ) [ 1 , 2 ] . There appears to be a strong consensus , with backup from a meta- analysis , on the preferential use of EN over PN [ 3 ] . The infection rate was especially used as an argument ; however , this is not substantiated in recent trials [ 1 , 2 ] . We have to consider how applicable this current knowledge is to all ICU patients . Early EN is still the preferred way of feeding [ 3 ] . Starting feeding early may improve the outcome of ICU patients . RCTs have all investigated ( supplemental parenteral )  energy delivery [ 4 ] . Only two trials have ‘ considered ’ protein : the PERMIT trial [ 5 ] ( protein supplemented , equal level ) and EAT-ICU trial [ 6 ] ( protein supplemented , higher level ) . Early energy delivery should be applied cautiously since it appears to be related to worse outcome in ICU patients [ 7 , 8 , 9 ] . Therefore , and from the perspective of clinical practice , the Swiss Supplemental PN ( SPN ) trial appears to provide the most logical design [10]—start with early EN and evaluate on day 3 what the level of energy delivery is ; when delivery levels are low ( < 60 % ) start supplementation PN . In clinical practice in our ICU the enteral feeding levels are high enough to avoid PN supplementation , which therefore restricts the specific indication to use PN . The focus of this research has been caloric delivery . There are more than enough observational data to support that higher protein delivery is associated with improved outcome in ICU patients [ 7 , 8 , 9 ] . These observational studies clearly show the benefit of higher protein delivery . However , they are considered relatively weak evidence since illness is considered a confounding factor in the relationship between delivery and outcome for which we can not completely adjust . R and omized trials have not been conducted , although two trials with r and omized high(er ) amino acid infusion are available and somewhat contradicting [ 11 , 12 ] . As with the studies on caloric delivery , the studies on protein have been hampered by insufficient knowledge on energy and protein metabolism under these (patho)physiological circumstances in the ICU patient [ 7 , 8 , 9 ] . Therefore , mechanistic studies on the protein physiology in ICU patients is an essential and current development . The Swedish group of Wernerman and Rooyackers has provided crucial information on the topic . They showed that it was possible to change protein balance during the early phase of admission to the ICU from negative to positive by 
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AUTHORS ' CONCLUSIONS Due to very low- quality evidence , we are uncertain whether early enteral nutrition , compared with delayed enteral nutrition , affects the risk of mortality within 30 days , feed intolerance or gastrointestinal complications , or pneumonia .
Due to very low- quality evidence , we are uncertain if early enteral nutrition with supplemental parenteral nutrition compared with delayed enteral nutrition with supplemental parenteral nutrition reduces mortality , infectious complications , or duration of mechanical ventilation .