***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: We measured energy expenditure ( MREE ) and nitrogen excretion ( UUN ) in patients with severe head injury r and omized to early parenteral ( TPN , n = 21 ) or jejunal ( ENT , n = 27 ) feeding  with identical formulations . The MREE rose to 2400 + /- 531 kcal/day in both groups and remained at 135 % + /- 26 % to 146 % + /- 42 % of predicted energy expenditure over 4 weeks . Nitrogen excretion peaked the second week at 33.4 + /- 10 ( TPN ) and 31.2 + /- 7.5 ( ENT ) g N/day . Both routes were equally effective at meeting nutritional goals ( 1.2 x MREE , 2.5 g protein/kg/day intake , stabilized albumin and transferrin levels ) . Infections were equally frequent : 1.86 episodes/TPN patient versus 1.89 episodes/ENT patient . While patient charges were much greater for TPN , the hospital costs were similar for TPN and ENT support regimens . These findings show that patients with head injuries are hypermetabolic for weeks , that only 27 % are capable of spontaneously eating nutritional requirements by discharge , and that either TPN or ENT support is equally effective when prescribed according to individual measurements of MREE and nitrogen excretion BACKGROUND & AIMS Nutritional monitoring of rapid turnover visceral protein is important in the recognition of malnutrition in patients admitted to the Intensive Care Unit ( ICU ) . We studied prealbumin and retinol-binding protein in patients who received three different kinds of artificial nutrition  in order to evaluate the appropriateness of artificial nutrition . METHODS 45 consecutive head injury patients received  enteral ( Group A ) , parenteral ( Group B ) or both enteral and parenteral nutrition ( Group C ) at r and om . We considered these parameters : prealbumin , retinol binding protein and nitrogen balance before ( T1 ) , after 3 ( T2 ) , 7 ( T3 ) and 11 ( T4 ) days after the beginning of study . Statistical analysis was performed with Kruskal-Wallis test and Bonferroni 's t -test . RESULTS Plasma prealbumin and Retinol binding protein ( RBP ) showed an increasing of basal values during the study period in all groups ( < < 0.0001 ) and more significantly in group A ( Enteral nutrition P < 0 . 001 vs Total parenteral nutrition ( TPN ) and Enteral P < < 0.01 vs Enteral and parenteral nutrition ) . CONCLUSION Data obtained in the present study indicate that a laboratory is essential for monitoring nutritional assessment and for checking the appropriateness of nutritional therapy . We found prealbumin to be the most sensitive measure and found it to be the test of choice for early assessment and intervention BACKGROUND Although early enteral feeding clearly reduces septic morbidity after blunt and penetrating trauma , data for head-injured patients are conflicting . This study examines the effects of early vs delayed enteral feedings on outcome in patients with severe closed-head injuries with a Glasgow Coma Scale ( GCS ) score greater than 3 and less than 11 . METHODS Thirty patients were prospect ively r and omized to receive an  immune-enhancing diet ( Impact with fiber ) early ( initiated < 72 hours after trauma ) delivered via an endoscopically placed nasoenteric tube ( Stay-Put ) or late ( administered after gastric ileus resolved ) . This formula was continued for 14 days or until the patient tolerated oral feeding . Goal rate of nutrition was 21 nonprotein cal/kg/d and 0.3 g N/kg/d . RESULTS Two patients in the early group were excluded due to inability to place the tube , and one patient in the late group died before 72 hours . Five of the remaining 27 died , 1 in the early group and 4 in the late group . There were no significant differences between the groups in length of stay , intensive care unit ( ICU ) days , significant infection , or GCS score . However , major infection correlated inversely with admission GCS score ( R = -0.6 , p < .003 ) . Time to reach a GCS score of 14 was significantly longer in patients with significant infections compared with those without ( p < .02 ) . CONCLUSIONS No difference in length of stay or infectious complications is shown in patients with severe closed-head injury when they are given early vs delayed feeding using an immune-enhancing formula . Severity of the head injury is closely associated with significant infection This prospect i ve r and omized controlled clinical trial compares the effects of early parenteral nutrition and traditional delayed enteral nutrition upon the outcome of head-injured patients . Thirty-eight head-injured patients were r and omly assigned to receive total parenteral nutrition ( TPN ) or st and ard enteral nutrition ( SEN ) . Clinical and nutritional data were collected on all patients until death or for 18 days of hospitalization . Survival and functional recovery were monitored in survivors for 1 year . Of the 38 patients , 18 were r and omized to the SEN group and 20 to the TPN group . Demographically , the two groups of patients were similar on admission . There was no significant difference in the severity of head injury between the two groups as measured by the Glasgow Coma Scale ( p = 0.52 ) . The outcome for the two groups was quite different , with eight of the 18 SEN patients dying within 18 days of injury , whereas no patient in the TPN group died within this period ( p less than 0.0001 ) . The basis for the improved survival in the TPN patients appears to be improved nutrition . The TPN patients had a more positive nitrogen balance ( p less than 0.06 ) , and a higher serum albumin level and total lymphocyte count . More adequate nutritional status may have improved the patients ' immunocompetence , result ing in decreased susceptibility to sepsis . The data from this study strongly support the favorable effect of early TPN on survival from head injury Fifty-one brain-injured patients with peak 24-hour admission Glasgow Coma Scale ( GCS ) scores of 4 to 10 were prospect ively r and omly assigned to receive total parenteral ( TPN ) or enteral ( EN ) nutrition .  Patients were studied from hospital admission to 18 days postinjury . Outcome was assessed by the Glasgow Outcome Scale at 3 months , 6 months , and 1 year postinjury . The TPN group received a significantly higher cumulative mean intake of protein than the EN group ( mean + /- st and ard error of the mean : 1.35 + /- 0.12 vs. 0.91 + /- 0.9 gm/kg/day ; p = 0.004 ) . Mean cumulative caloric balance was also significantly higher in the TPN than in the EN group ( 75.6 % + /- 5.13 % vs. 59 % + /- 4.26 % ; p = 0.02 ) . Nitrogen balance was significantly more negative in the EN group during the 1st week postinjury ( p = 0.002 ) . The incidence of pneumonia , urinary tract infections , septic shock , and infections was not significantly different between groups . Classic nutritional assessment parameters such as anergy screens , total lymphocyte counts , and albumin levels were not significantly different between groups . The 11 patients in the EN group who did not tolerate tube feedings for 1 week postinjury had a significantly higher incidence of septic shock ( p = 0.008 ) . The change over time in GCS scores between groups was significantly different , with the TPN group showing a mean four-point increase in GCS score compared with a three-point increase in the EN group ( p = 0.02 ) . At 3 months the TPN group had a significantly higher percentage of favorable outcomes ( 43.5 % vs. 17.9 % , respectively ; p = 0.05 ) . At 6 months , 43.5 % of the TPN group had a favorable outcome while 32.1 % of the EN group had a favorable outcome ( p = 0.29 ) . By 1 year , 47.8 % of the TPN group and 32.1 % of the EN group had a favorable outcome ( p = 0.20 ) . In conclusion , more calories and protein usually can be administered to acute brain injury patients via the TPN route than by EN feedings via nasogastric or nasoduodenal routes . Traditional parameters for nutritional assessment are not useful in study ing the efficacy of nutritional support during the first 2 weeks after head injury . Neurological recovery from head injury occurs more rapidly in patients with better early nutritional support OBJECTIVE To compare metabolic , nutritional and epidemiological data in two groups of patients , one receiving total enteral nutrition , via nasoenteric tube , and one receiving both enteral and parenteral nutrition .  DESIGN A prospect i ve , r and omized study . SETTING A general ICU , with both medical and surgical patients , in a big regional University and National Health Service hospital . PATIENTS 24 patients requiring Intensive Care after major surgery or because suffering from severe head injury or major neurological impairment . INTERVENTIONS All patients initially received total parenteral nutrition : after 4 days 12 patients were " weaned " to total enteral nutrition and 12 stayed on mixed parenteral and enteral nutrition . LABORATORY INVESTIGATIONS AND OBSERVATIONAL DATA : Blood levels of albumin , prealbumin , transferrin , ALT , AST , bilirubin , blood urea , blood glucose , total linfocite count , and nutritional and epidemiological data such as nitrogen balance , calorie intake , diarrhea incidence , blood and sputum cultures and radiologic evidence of pneumonia are analysed . RESULTS At T1 , NET patients were able to reduce their nitrogen losses ( 0.27.1 g/kg + /-0.12 vs 0.35 + /- 0.13 at TO ; p < 0.05 ) and improve nitrogen balance ( -9 + /- 7 vs -2 + /- 6 at T0 ; p < 0.05 ) ; they also had a better total linfocite count ( 2034 + /- 304 vs. 1413 + /- 360 of the MISTA group ; p < 0.05 ) , and a lower incidence of pneumonia as documented by sputum cultures and radiograms . CONCLUSIONS Patients fed with both parenteral and enteral nutrition did no better than those on total enteral nutrition as far as nutritional and metabolic indices were concerned ; they also seemed more prone to infections than those on total enteral nutrition , indicating that mixed nutrition may result in more stable feeding , but this does not seem to have any beneficial nutritional , immunological and metabolic effect A comparative nutritional study in brain-injured patients ( BIP ) was performed to assess the influence of a combined enteral-parenteral nutrition ( CN ) and a total parenteral nutrition ( TPN ) on protein catabolism in the early posttraumatic period . 20 male BIP ( Glasgow coma scale 5–7 ) were r and omized to one of the two feeding regimes . Nutritional support was based on 150–175 % basic energy expenditure . Amino acid intake was 1.4 g/kg/day in the TPN and 2.4 g/kg/day in the CN group . Negative nitrogen balance ( NNB ) averaged x ( SEM=3.06 g/m2/day ) in the TPN group and x ( SEM=2.33 g/m2/day ) in the CN group . Between both feeding regimes not statistically significant differences could be observed concerning mortality , N-balance , creatinine and 3-methylhistidine excretions . Protein concentration of the regurgitated gastric fluid was significantly higher in the CN than in the TPN study group . Data imply that both alimentary regimes are of similar value , but BIP with imparired gastric function , such as high tube reflux , are better treated by TPN Animal investigations suggest that administration of hyperosmolar total parenteral nutrition ( TPN ) solutions may potentiate cerebral edema following head injury . Intravenous nutrition ( TPN ) is often required after head injury due to intolerance to enteral feeding ( EN ) . This study evaluates the effect of TPN on intracranial pressure ( ICP ) measurements in severely brain-injured patients . Ninety-six severely brain-injured patients were r and omly assigned to receive TPN or EN and were studied from hospital admission until 18 days postinjury . The TPN was started within 48 hours postinjury and the EN was started when tolerated . Peak daily ICP was not significantly different on admission and over time ( overall mean + /- st and ard error of the mean 32.01 + /- 1.62 for TPN versus 32.5 + /- 1.25 for EN ) . Intracranial pressure was greater than 20 mm Hg in 75 % of TPN patients and 73 % of EN patients . Conventional therapy failed to control elevated ICP in 36 % of TPN patients and 38 % of EN patients . Of these patients , subsequent barbiturate therapy failed to control ICP in 56 % of TPN patients and 64 % of EN patients . Serum osmolality was not significantly different between groups at admission or over the course of the study . The TPN group tended to have higher mean serum glucose levels for the first 13 days postinjury , while the EN group had a higher mean serum glucose content thereafter , but these differences were not statistically significant . This study shows that TPN 
    Output:
    
Enteral nutrition : jejunal versus gastric .
REVIEW ER 'S CONCLUSIONS This review suggests that early feeding may be associated with a trend towards better outcomes in terms of survival and disability .