***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: PURPOSE This study aim ed to evaluate the effects of not measuring gastric residual volume ( GRV ) in intensive care patients on a mechanical ventilator and receiving enteral feeding on the feeding intolerance , gastroesophageal reflux ( GER ) risk , and nutritional adequacy . METHODS This r and omized clinical study was performed in 2 medical intensive care units of 2 university hospitals in Ankara , Turkey . The patients were r and omized into 2 groups . In the group with GRV monitoring , GRV was measured 3 times a day , and the GRV threshold was accepted as 250 mL. In addition , 24-hour pH monitoring was used in this group to assess the risk of GER . In the group without GRV monitoring , GRV was not measured . The patients were followed-up for 5 days . RESULTS The feeding targets were reached more quickly in the group without GRV monitoring ( n = 26 ) with no increase in the complication rate ( P < .05 ) . No significant relationship was found between GRV and GER in the group with GRV monitoring ( n = 25 ) ( P > .05 ) . CONCLUSION The discrepancies in GRV measurement make it unreliable for monitoring feeding intolerance and GER . The use of GRV measurements may therefore be discontinued as part of the st and ard care protocol in medical intensive care units Nursing care of patients with enteral feeding tubes is common in the intensive care unit but the evidence that surrounds the practice is limited . Recent research by Juve-Udina and colleagues ( 2010 ) " To return or to discard ? R and omised trial on gastric residual volume management " compares two methods of managing gastric residual volume . This critique provides a brief summary of their research and critically appraises the paper . The implication s for nursing practice are discussed BACKGROUND Enteral nutrition ( EN ) tolerance is often monitored by aspirating stomach contents by syringe at prescribed intervals . No studies have been conducted to assess the most appropriate time interval for aspirating gastric tubes . We compared gastric tube aspirations every 4 hours ( usual care ) with a variable regimen ( up to every 8 hours aspirations ) . METHODS This r and omized controlled trial ( RCT ) enrolled patients who stayed in the intensive care unit ( ICU ) for > 48 hours , had a gastric tube , and were likely to receive EN for 3 or more days . Patients were r and omized ( computer-generated r and omization )  to either the control ( every 4 hours ) or intervention group ( variable regimen ) . The primary outcome was number of gastric tube aspirations per day from r and omization until EN was ceased or up to 2 weeks postr and omization . RESULTS Following Institutional Ethics Committee approval , 357 patients were recruited ( control group , n = 179 ; intervention group , n = 178 ) . No differences were found in age , sex , worst APACHE II score , or time to start of EN . In the intention-to-treat analysis , the intervention group had fewer tube aspirations per day ( 3.4 versus 5.4 in the control group , P < .001 ) . Vomiting/regurgitation was increased in the intervention group ( 2.1 % versus 3.6 % , P = .02 ) . There were no other differences in complications . CONCLUSION This is the first RCT to examine the frequency of gastric tube aspirations . The frequency of gastric tube aspirations was reduced in the variable-regimen group with no increase in risk to the patient . Reducing the frequency of aspirations saves nursing time , decreases risk of contamination of feeding circuit , and minimizes risk of body fluid exposure BACKGROUND Research -based st and ards do not exist for the management of gastric residual volumes from feeding tubes . Withdrawing and returning residual volumes can lead to clogged tubes and exposes patients to possible contamination of the feeding system . However , discarding residual volumes may place patients at risk for electrolyte imbalance and may alter fluid or nutritional balance . OBJECTIVES To investigate the effects of discarding versus returning gastric residual volumes on body weight , serum electrolyte levels , and the rate of complications associated with tube feeding . METHODS Thirty-five subjects receiving enteral feedings were recruited from intensive care units at 3 Midwest hospitals and r and omized to a discard group or a return group . Eighteen sets of usable data were obtained . RESULTS Repeated- measures analysis of variance indicated no significant differences between the 2 groups for any of the variables . Complications related to enteral feedings were more common in the return group ( n = 8) , which had 2 episodes of tube clogging and 1 episode of diarrhea and nausea . None of these complications were experienced by patients in the discard group ( n = 10 ) . CONCLUSIONS Both groups had significant numbers of complications , including a total of 15 episodes , 7 in the discard group and 8 in the return group , of feeding delays due to high gastric residual volumes . Although serum electrolyte levels did not differ significantly between the 2 groups , potassium levels tended to be lower in the discard group . Considerations for the care of critically ill patients with feeding tubes are discussed in light of these findings BACKGROUND The control of gastric residual volume ( GRV ) is a common nursing intervention in intensive care ; however the literature shows a wide variation in clinical practice regarding the management of GRV , potentially affecting patients ' clinical outcomes . The aim of this study is to determine the effect of returning or discarding GRV , on gastric emptying delays and feeding , electrolyte and comfort outcomes in critically ill patients . METHOD A r and omised , prospect i ve , clinical trial design was used to study 125 critically ill patients , assigned to the return or the discard group . Main outcome measure was delayed gastric emptying . Feeding outcomes were determined measuring intolerance indicators , feeding delays and feeding potential complications . Fluid and electrolyte measures included serum potassium , glycaemia control and fluid balance . Discomfort was identified by significant changes in vital signs . RESULTS Patients in both groups presented similar mean GRV with no significant differences found ( p=0.111 ) , but participants in the intervention arm showed a lower incidence and severity of delayed gastric emptying episodes ( p=0.001 ) . No significant differences were found for the rest of outcome measurements , except for hyperglycaemia . CONCLUSIONS The results of this study support the recommendation to reintroduce gastric content aspirated to improve GRV management without increasing the risk for potential complications Objective To compare the effects of increasing the limit for gastric residual volume ( GRV ) in the adequacy of enteral nutrition . Frequency of gastrointestinal complications and outcome variables were secondary goals . Design An open , prospect i ve , r and omized study . Setting Twenty-eight intensive care units in Spain . Patients Three hundred twenty-nine intubated and mechanically ventilated adult patients with enteral nutrition ( EN ) .  Interventions EN was administered by nasogastric tube . A protocol for management of EN-related gastrointestinal complications was used . Patients were r and omized to be included in a control ( GRV = 200 ml ) or in study group ( GRV = 500 ml ) . Measurements and results Diet volume ratio ( diet received/diet prescribed ) , incidence of gastrointestinal complications , ICU-acquired pneumonia , days on mechanical ventilation and ICU length of stay were the study variables . Gastrointestinal complications were higher in the control group ( 63.6 vs. 47.8 % , P = 0.004 ) , but the only difference was in the frequency of high GRV ( 42.4 vs. 26.8 % , P = 0.003 ) . The diet volume ratio was higher for the study group only during the 1st week ( 84.48 vs. 88.20 % ) ( P = 0.0002 ) . Volume ratio was similar for both groups in weeks 3 and 4 . Duration of mechanical ventilation , ICU length of stay or frequency of pneumonia were similar . Conclusions Diet volume ratio of mechanically ventilated patients treated with enteral nutrition is not affected by increasing the limit in GRV . A limit of 500 ml is not associated with adverse effects in gastrointestinal complications or in outcome variables . A value of 500 ml can be equally recommended as a normal limit for GRV OBJECTIVES There is a lack of evidence regarding the economic effects of nutrition support in patients at nutritional risk . The aim of this study was to perform a cost-effectiveness analysis by comparing an adequate nutrition support cohort  with a  no-support cohort .  METHOD A prospect i ve observational study was performed in the surgical and medical gastroenterology wards . We identified patients at nutritional risk and the provision of nutrition support by the staff , unaware of the risk status , was recorded . Cost data were obtained from each patient 's statement of accounts , and effectiveness was measured by the rate of infectious complication . To control for potential confounding variables , the propensity score method with matching was carried out . The incremental cost-effectiveness ratio was calculated based on the matched population . RESULTS We screened 3791 patients , and 440 were recruited for the analysis . Patients in the nutrition support cohort had a lower incidence of infectious complications than those in the no-support cohort ( 9.1 versus 18.1 % ; P = 0.007 ) . This result was similar in the 149 propensity matched pairs ( 9.4 versus 24.2 % ; P < 0.001 ) . The median hospital length of stay was significantly reduced among the matched nutrition support patients ( 13 versus 15 d ; P < 0.001 ) . The total costs were similar among the matched pairs ( US $ 6219 versus $ 6161 ) . The incremental cost-effectiveness analysis suggested that nutrition support cost US $ 392 per patient prevented from having infectious complications . CONCLUSION Nutrition support was associated with fewer infectious complications and shorter length of stay in patients at nutritional risk . The incremental cost-effectiveness ratio indicated that nutrition support had not increased costs significantly Background :  Delayed gastric emptying ( GE ) impedes enteral nutrient ( EN ) delivery in critically ill children . We examined the correlation between ( a ) bedside EN intolerance assessment s , including gastric residual volume ( GRV ) ; ( b ) delayed GE ; and ( c ) delayed EN advancement . Material s and Methods : We prospect ively enrolled patients ≥1 year of age , eligible for gastric EN and without contraindications to acetaminophen .  Gastric emptying was determined by the acetaminophen absorption test , specifically the area under the curve at 60 minutes ( AUC60 ) . Slow EN advancement was defined as delivery of < 50 % of the prescribed EN 48 hours after study initiation . EN intolerance assessment s ( GRV , abdominal distension , emesis , loose stools , abdominal discomfort ) were recorded . Results : We enrolled 20 patients , median 11 years ( 4.4–15.5 ) , 50 % male . Sixteen ( 80 % ) patients had delayed GE ( AUC60 < 600 mcg·min/mL ) and 7 ( 35 % ) had slow EN advancement . Median GRV ( mL/kg ) for patients with delayed vs normal GE was 0.43 ( 0.113–2.188 ) vs 0.89 ( 0.06–1.91 ) , P = .9635 . Patients with slow vs rapid EN advancement had median GRV ( mL/kg ) of 1.02 mL/kg ( 0.20–3.20 ) vs 0.27 mL/kg ( 0.06–1.62 ) , P = .3114 , and frequency of altered EN intolerance assessment s of 3/7 ( 42.9 % ) vs 5/13 ( 38.5 % ) , P = 1 . Median AUC60 for patients with slow vs rapid EN advancement was 91.74 mcg·min/mL ( 53.52–143.1 ) vs 449.5 mcg·min/mL ( 173.2–786.5 ) , P = .0012 . Conclusions : A majority of our study cohort had delayed GE . Bedside EN intolerance assessment s , particularly GRV , did not predict delayed GE or rate of EN advancement . Delayed gastric emptying predicted slow EN advancement . Novel tests for delayed GE and EN intolerance are needed This study examined the effect of gastric feeding regimens , either continuous or intermittent , on fourth hourly gastric residual volumes ( GRV ) in a group of critically ill paediatric patients where delayed gastric emptying is defined as a GRV greater than 5ml/kg . A r and omised controlled trial was conducted in a tertiary paediatric intensive care unit ( PICU ) , with 45 participants being r and omly assigned to either the continuous ( n=22 ) or intermittent ( n=23 ) gastric feeding groups . Participants remained in the assigned group for the duration of the study and , fourth hourly , GRV were assessed to monitor the incidence of delayed gastric emptying .  Both groups were similar in age , weight , gender , diagnosis , paediatric index mortality ( PIM ) score , and usage of pharmacological agents known to affect the gastrointestinal tract . No differences emerged in study duration or the volume of administered enteral formula ( ml/kg/day ) . The intermittent feeding group commenced enteral feeding earlier in the PICU admission ( 13.0 hours versus 18. 
    Output:
    
Conclusions No evidence confirms that returning residual gastric aspirates provides more benefits than discarding them without increasing potential complications .