Systematic Review of Enteral vs Parenteral Nutrition in the ICU (Nutrition, 2004) [MEDLINE]
Enteral Nutrition Decreases Infectious Complications, as Compared to Parenteral Nutrition
Enteral Nutrition is Less Expensive than Parenteral Nutrition
EPaNIC Trial Comparing Early vs Late Initiation of TPN (NEJM, 2011) [MEDLINE]: Belgian randomized multi-center trial comparing early initiation of TPN (European guidelines: within 48 hrs of ICU admission; n = 2312) with late initiation (American and Canadian guidelines: within 8 days of ICU admission; n = 2328) in adults in the ICU
No Difference in ICU Mortality Rate, Hospital Mortality, and 90-Day Mortality Rate Between the Groups
Late-Initiation Group Had a 6.3% Increase in Likelihood of Being Discharged Alive Earlier from the ICU and Hospital
Late-Initiation Group Had Fewer ICU Infections (22.8% vs. 26.2%, p = 0.008)
Late-Initiation Group Had a Lower Incidence of Cholestasis (p < 0.001)
Late-Initiation Group Had a Relative Reduction of 9.7% in the Proportion of Patients Requiring >2 Days of Mechanical Ventilation (p = 0.006)
Late-Initiation Group Had a Median Reduction of 3 Days in the Duration of Renal Replacement Therapy (p = 0.008)
Late-Initiation Group Had a Mean Reduction in Health Care Costs of About $1,600 (p = 0.04)
Late-Initiation Group Had No Decrease in Functional Status at Hospital Discharge
Study of Early Parenteral Nutrition in Critically Ill Patients with Short-Term Relative Contraindications to Early Enteral Nutrition (JAMA, 2013) [MEDLINE]: n = 1372 patients
No Impact on 60-Day Mortality Rate, as Compared to Standard Care
Early Parenteral Nutrition Strategy Resulted in Fewer Invasive Ventilation Days, But Had No Effect on ICU or Hospital Stay
Swiss Randomized Trial of Supplemental TPN in Critically Ill Patients (Lancet, 2013) [MEDLINE]: n = 305 patients
Supplemental TPN (in Addition to Enteral Nutrition) Starting 4 Days After ICU Admission Decreased Nosocomial Infection Rates
British CALORIES Trial Comparing Early Enteral vs Parenteral Nutrition in the ICU (NEJM, 2014) [MEDLINE]: randomized trial in 33 English ICU’s comparing enteral vs parenteral nutrition (n = 2388)
No Difference in 30-day Mortality Between the Groups
Caloric Intake was Similar in the Groups, with the Target Intake Not Achieved in Most Patients
Total Parenteral Nutrition Group Had Significantly Decreased Rates of Hypoglycemia and Vomiting, as Compared to the Enteral Group
No Difference in Rate of Infectious Complications or Other Adverse Events
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Enteral Nutrition Should Be Used Over TPN (Quality of Evidence: Very Low-Low)
Enteral Nutrition is Associated with Decreased Infectious Complications (Pneumonia and Central Line Infections in Most Patients/Abdominal Abscess in Trauma Patients) and Decreased ICU Length of Stay
In Patients with Low Nutrition Risk (NRS 2002 ≤3 or NUTRIC score ≤5), Exclusive TPN Should Be Withheld for the First 7 Days Following ICU Admission, if PO Intake and Enteral Nutrition are Not Adequate/Possible (Quality of Evidence: Very Low)
In Patients with High Nutrition Risk (NRS 2002 ≥5 or NUTRIC score ≥5) or Severely Malnourished, Exclusive TPN Should Be Started as Soon as Possible Following ICU Admission, if PO Intake and Enteral Nutrition are Not Adequate/Possible (Quality of Evidence: Expert Consensus)
In Patients with Low or High Nutrition Risk, Supplemental TPN Should Be Considered After 7-10 Days if Unable to Meet >60% of Energy and Protein Requirements by Enteral Route Alone (Quality of Evidence: Moderate)
Initiating Supplemental TPN Prior to 7-10 Days May Be Harmful
Indications for Enteral Nutrition (in Specific Clinical Situations)
Enteral Nutrition in the Setting of Acute Pancreatitis (see Acute Pancreatitis)
Clinical Efficacy
Meta-Analysis of Nasogastric vs Nasojejunal Feeding in Severe Acute Pancreatitis (Crit Care, 2013) [MEDLINE]
Nasogastric Feeding is Safe and Well-Tolerated, as Compared to Nasojejunal Feeding
Critique: small study, needs to be replicated
Dutch PYTHON Trial Comparing Early Enteral Nutrition with Oral Intake in Severe Acute Pancreatitis (NEJM, 2014) [MEDLINE]: n = 208
If Oral Intake was Inadequate in the Latter Oral Intake Group (“On-Demand” Group), Enteral Nutrition was Started
In Patients with Acute Pancreatitis at High Risk for Complications, Early Enteral Nutrition (within 24 hrs of ED Presentation) was Not Superior to Oral Intake (Started After 72 hrs), in Terms of Decreasing the Infection Rate or Mortality Rate within 6 mo
Systematic Review of Timing of Nutrition in Acute Pancreatitis (Ann Intern Med, 2017) [MEDLINE]: 11 trials (n = 948)
Mild-Moderate Pancreatitis: early feeding was associated with decreased length of stay in 4/7 studies (including 2/3 with low risk of bias)
Other Outcomes were Heterogeneous and Variably Reported, But No Study Demonstrated an Increased Risk of Adverse Events with Early Feeding
Severe Pancreatitis: limited evidence demonstrated no difference between early and delayed feeding
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Definitions
Mild Acute Pancreatitis: absence of organ failure and local complications
Moderate Acute Pancreatitis: transient organ failure (SBP <90 mm Hg, pO2/FIO2 ratio ≤300, or AKI with Cr ≥1.9 mg/dL) lasting <48 hrs with presence of local complications (pseudocyst, abscess, necrosis)
Severe Acute Pancreatitis: persistent organ failure lasting >48 hrs from the time of admission
Initial Nutritional Assessment Should Evaluate Disease Severity to Guide Nutritional Therapy (Expert Consensus)
Since Disease Severity May Change Quickly, Frequent Reassessment of Feeding Tolerance and the Need for Specialized Nutritional Therapy is Suggested
Mild Acute Pancreatitis
Oral Diet (Advanced As Tolerated) is Recommended (Quality of Evidence: Very Low)
If an Unexpected Complication Develops or There is a Failure to Advance Oral Diet within 7 Days, Specialized Nutritional Therapy Should Be Considered (Quality of Evidence: Very Low)
Moderate-Severe Acute Pancreatitis
Nasogastric tube Placement and Start of Trophic Tube Feedings with Advancement (As Tolerated) to Target Rate Within 24-48 hrs is Recommended (Quality of Evidence: Very Low)
If Intolerance Develops Occurs, the Following Measures Should Be Taken to Improve Tolerance (Expert Consensus)
Minimizing the Period of Ileus by Starting Enteral Nutrition as Soon as Possible within the First 48 hrs of Admission to the ICU
Diverting the Infusion of Enteral Feeding to a More Distal Gastrointestinal Tract Site (i.e. Jejunal Feeding): feeding into the jejunum is associated with a lesser degree of pancreatic stimulation, which increases the likelihood of the feedings being successful and circumvents the problem of gastric dysmotility
Changing from a Standard Polymeric Enteral Feeding Formula to One Which Contains Small Peptides and Medium Chain Triglycerides (MCT) or to One that is a Nearly Fat-Free Elemental Formulation
Switching from Bolus to Continuous Infusion of Enteral Feeding
Severe Acute Pancreatitis
Standard Polymeric Tube Feed Formulation is Recommended (Quality of Evidence: Very Low)
Enteral Nutrition is Recommended (by Gastric or Jejunal Route) Over Total Parenteral Nutrition (TPN) in Severe Pancreatitis (Quality of Evidence: Low)
No Difference Between Gastric or Jejunal Feeding with Regard to Tolerance or Clinical Outcome (Quality of Evidence: Low)
Probiotics Should Be Considered with Early Tube Feeding in Severe Pancreatitis (Quality of Evidence: Low)
When Enteral Nutrition is Not Possible, Parenteral Nutrition Can Be Considered After 1 Week From the Onset of the Acute Pancreatitis Episode (Expert Consensus)
OMEGA Trial Examining the Effect of Supplementation with Omega-3 (n-3) Fatty Acids (Docosahexaenoic Acid = DHA, Eicosapentaenoic Acid = EPA), γ-Linolenic Acid, and Antioxidants in Acute Lung Injury (JAMA, 2011) [MEDLINE]
Enteral Omega-3 Fatty Acids, Gamma-Linolenic Acid, and Antioxidants Did Not Improve the Primary Endpoint of Ventilator-Free Days or Other Clinical Outcomes in Patients with Acute Lung Injury and May Be Harmful
EDEN Trial of Enteral Nutrition in Acute Lung Injury (JAMA, 2012) [MEDLINE]
Initial Trophic Feeding (For Up to 6 Days) Did Not Improve Ventilator Days, 60-Day Mortality, or Infectious Complications, as Compared to Full Feeding
Full Feeding Group Had More Gastrointestinal Intolerance (Vomiting, Constipation, and Elevated Gastric Residual Volumes): they received more pro-kinetic agents
Trial of Glutamine and Antioxidants in Critically Ill Patients with Mutiorgan Failure on Mechanical Ventilation (NEJM, 2013) [MEDLINE]
Early Provision of Glutamine or Antioxidants Did Not Improve Clinical Outcomes, and Glutamine was Associated with an Increase in Mortality Among Critically IIl Patients with Multiorgan Failure
Australia/New Zealand TARGET Trial of Energy-Dense Enteral Nutrition in Patients on Mechanical Ventilation (NEJM, 2018) [MEDLINE]
In Patients on Mechanical Ventilation, the Energy-Dense Enteral Nutrition Had No Impact on the 90-Day Mortality Rate, as Compared to Routine Enteral Nutrition
Clinical Efficacy (During Prone Ventilation)
Study of Early Enteral Nutrition in Association with Prone Ventilation (Crit Care Med, 2004) [MEDLINE]
Early Enteral Nutrition is Poorly-Tolerated in Patients Who are Prone-Ventilated
Prokinetic Agents, Transpyloric Feeding, and Semirecumbency Should Be Considered to Enhance Gastric Emptying and to Prevent Vomiting in This Population
Study of Head of Bed Elevation in Enteral Nutrition in Association with Prone Ventilation (Clin Nutr, 2010) [MEDLINE]:
Elevation (25 Degrees) Increased Acceleration of Tube Feedings to Target Rate
Erythromycin Improved Delivery of Enteral Nutrition
Study of Enteral Nutrition in Association with Prone Ventilation (J Parenter Enteral Nutr, 2016) [MEDLINE]
Enteral Nutrition in Association with Prone Ventilation is Feasible, Safe, and Not Associated with an Increased Risk of Gastrointestinal Complications
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
High Fat/Low Carbohydrate Tube Feedings are Not Recommended in Patients with Acute Respiratory Failure (Quality of Evidence: Very Low)
Either Trophic or Full Feedings are Acceptable in ARDS with an Expected Duration of Mechanical Ventilation ≥72 hrs (Quality of Evidence: High)
Both Trophic and Full Feeding Strategies Have Similar Outcomes for the First Week of Hospitalization
In Acute Respiratory Failure, Fluid-Restricted, Energy-Dense Enteral Formulations Should Be Considered, Especially in the State of Volume Overload (Quality of Evidence: Expert Consensus)
Supplemental Antioxidant Vitamins (Vitamins E and C) and Trace Minerals (Selenium, Zinc, Copper) May Be Beneficial in Burns, Trauma, Critical Illness Requiring Mechanical Ventilation (Quality of Evidence: Low)
Supplemental Omega-3 (n-3) Fatty Acids (Docosahexaenoic Acid = DHA, Eicosapentaenoic Acid = EPA) Are Not Recommended in ARDS
Enteral Nutrition in the Setting of Hemodynamic Instability
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Tube Feedings Should Be Withheld Until the Patient is Fully Resuscitated and/or Stable (Quality of Evidence: Expert Consensus)
Enteral Nutrition in the Setting of Liver Disease (see Cirrhosis)
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Dry Weight/Usual Weight Should Be Used Instead of Actual Weight for Predictive Equations (Quality of Evidence: Expert Consensus): due to ascites, intravascular volume depletion, edema, portal hypertension, and hypoalbuminemia
Routine Tube Feeding Formulations are Recommended Over Branched-Chain Amino Aid (BCAA) Formulations in Patients with Hepatic Encephalopathy (Quality of Evidence: Expert Consensus)
Enteral Nutrition Should Be Used Preferentially in the Setting of Liver Disease (Quality of Evidence: Expert Consensus): due to the risk of worsened hepatic dysfunction with prolonged TPN use
Enteral Nutrition in the Setting of an Open Abdomen
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Early Tube Feeding Within 24-48 hrs is Recommended in the Absence of Bowel Injury (Quality of Evidence: Expert Consensus)
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Patients Receiving Frequent Hemodialysis or Continuous Renal Replacement Therapy (CRRT) SHould Receive Increased Protein (Max: 2.5 g/kg/day)
Enteral Nutrition in the Setting of Sepsis (see Sepsis)
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Use of Exclusive/Supplemental Parenteral Nutrition are Not Recommended in the Acute Phase of Sepsis, Regardless of Degree of Nutrition Risk (Quality of Evidence: Very Low)
Benefits of Use of Selenium, Zinc, and Antioxidants in Sepsis are Unclear (Quality of Evidence: Moderate)
Immune Modulating Formulations are Not Recommended in Sepsis (Quality of Evidence: Moderate)
Enteral Nutrition in the Setting of Trauma
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Immune-Modulating Formulations Containing Arginine and Fish Oils Should Be Considered in Severe Trauma (Quality of Evidence: Very Low)
Enteral Nutrition in the Setting of Traumatic Brain Injury (TBI) (see Traumatic Brain Injury)
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Immune-Modulating Formulations Containing Arginine and EPA/DHA are Recommended in Traumatic Brain Injury (TBI) (Quality of Evidence: Expert Consensus)
Supplemental Antioxidant Vitamins (Vitamins E and C) and Trace Minerals (Selenium, Zinc, Copper) May Be Beneficial in Burns, Trauma, Critical Illness Requiring Mechanical Ventilation (Quality of Evidence: Low)
Administration
Enteral Nutrition Formulation
Clinical Efficacy
Trial of Glutamine and Antioxidants in Critically Ill Patients with Mutiorgan Failure on Mechanical Ventilation (NEJM, 2013) [MEDLINE]: early provision of glutamine or antioxidants did not improve clinical outcomes, and glutamine was associated with an increase in mortality among critically ill patients with multiorgan failure
OMEGA Trial of Enteral Omega-3 Fatty Acids, Gamma-Linolenic Acid, and Antioxidants in Acute Lung Injury (JAMA, 2011) [MEDLINE]: did not improve the primary end point of ventilator-free days or other clinical outcomes in patients with acute lung injury and may be harmful
Recommendations-Fiber Content (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Fermentable Soluble Fiber (fructo-oligossaccharides or inulin; 10-20 g/day) is Suggested as an Additive in All Hemodynamically Stable MICU/SICU Patients on a Standard Enteral Formulation, if There is Evidence of Diarrhea (Quality of Evidence: Expert Consensus)
Recommendations-Protein Content (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Enteral Nutrition Should Contain 1.2–2.0 g/kg of Actual Body Weight Per Day (Quality of Evidence: Very Low): higher in burn or trauma settings
Recommendations-Formulation/Supplementation (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Standard Polymeric Formulas Should Be Used Over Specialty/Disease-Specific Formulas (Quality of Evidence: Expert Consensus)
Immune-Modulating Formulations (Arginine with Other Agents, Including Eicosapentaenoic Acid = EPA, Docosahexaenoic Acid = DHA, Glutamine, Nucleic acid) Should Not Be Routinely Used in the MICU (Quality of Evidence: Very Low)
Immune-Modulating Formulations Containing Arginine and Fish Oils Should Be Considered in Severe Trauma (Quality of Evidence: Very Low)
Immune-Modulating Formulations Containing Arginine and Fish Oils Should Be Used in Postoperative Patients in the SICU
Immune-Modulating Formulations Containing Arginine and EPA/DHA are Recommended in Traumatic Brain Injury (TBI)
High Fat/Low Carbohydrate Tube Feedings are Not Recommended in Patients with Acute Respiratory Failure (Quality of Evidence: Very Low)
Supplemental Omega-3 (n-3) Fatty Acids (Docosahexaenoic Acid = DHA, Eicosapentaenoic Acid = EPA) Are Not Recommended in ARDS
Supplemental Antioxidant Vitamins (Vitamins E and C) and Trace Minerals (Selenium, Zinc, Copper) May Be Beneficial in Burns, Trauma, Critical Illness Requiring Mechanical Ventilation (Quality of Evidence: Low)
Supplemental Glutamine is Not Recommended in Critically Ill Patients (Quality of Evidence: Moderate)
Timing of Enteral Nutrition Initiation
Rationale
Enteral Nutrition Maintains the Functional Integrity of the Gut: by maintaining tight junctions between the intraepithelial cells, stimulating blood flow, and inducing the release of trophic endogenous agents (cholecystokinin, gastrin, bombesin, and bile salts)
Enteral Nutrition Modulates Stress and Systemic Immune Responses
Enteral Nutrition Attenuates Disease Severity
Clinical Efficacy
Trial of Early Enhanced Enteral Nutrition in Mechanically Ventilated Patients with Head Injury (Crit Care Med, 1999) [MEDLINE]
Enhanced Enteral Nutrition Accelerated Neurologic Recovery and Decreased Both the Incidence of Major Complications (Infectious Complications, etc) and Post-Injury Inflammatory Responses (C-Reactive Protein/Albumin Ratio)
Study of “Best Achievable” Practice for Nutrition in the ICU (Crit Care Med, 2010) [MEDLINE]
Average Time to Start Enteral Nutrition in Study: 46.5 hrs
Average Nutritional Adequacy for Energy Needs: only 59%
Average Nutritional Adequacy for Protein Needs: only 60%
ARDS Network EDEN Trial of Initial Trophic vs Full Enteral Nutrition in Acute Lung Injury (JAMA, 2012) [MEDLINE]
Initial Trophic Feeding (For Up to 6 Days) Did Not Improve Ventilator Days, 60-Day Mortality, or Infectious Complications, as Compared to Full Feeding
Full Feeding Group Had More Gastrointestinal Intolerance (Vomiting, Constipation, and Elevated Gastric Residual Volumes): they received more promotility agents
One Year Follow-Up of the ARDS Network EDEN Trial of Trophic vs Full Enteral Feeding in Acute Lung Injury (BMJ, 2013) [MEDLINE]
In Survivors of Acute Lung Injury, There was No Difference in Physical Function, Survival, or Multiple Secondary Outcomes at 6 or 12 mo After Initial Trophic vs Full Enteral Feeding
One Year Follow-Up of Physical and Cognitive Performance in the ARDS Network EDEN Trial of Trophic vs Full Enteral Feeding in Acute Lung Injury (Am J Respir Crit Care Med, 2013) [MEDLINE]
EDEN Trial Survivors Performed Below Predicted Values for Physical and Cognitive Performance at 6 and 12 mo with Some Improvement Over Time
Initial Trophic vs Full Enteral Feeding for the First 6 Days Did Not Impact Physical or Cognitive Outcomes
Permissive Underfeeding (40-60% of Calculated Caloric Requirement) vs Target (70-100% of Calculated Caloric Requirement) Enteral Feeding in Adult Critically Ill Patients (PermiT) Trial (NEJM, 2015) [MEDLINE]
Permissive Underfeeding Did Not Impact the 90-Day Mortality Rate, Feeding Intolerance, Incidence of Diarrhea, ICU-Acquired Infection Rate, ICU Length of Stay, or Hospital Length of Stay
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Enteral Nutrition Should Be Initiated Within 24-48 hrs in Patients Who are Unable to Maintain Their Nutrition Voluntarily (Quality of Evidence: Very Low)
Presence of Bowel Sounds/Passing of Flatus or Stool are Not Required for the Initiation of Enteral Nutrition (Quality of Evidence: Expert Consensus)
In Patients at High Nutrition Risk (NRS 2002 ≥5 or NUTRIC Score ≥5, Without IL-6), Enteral Nutrition Should Be Advanced as Quickly As Tolerated Within the First 24-48 hrs (Quality of Evidence: Expert Consensus): attempt to provide >80% of estimated/calculated goal energy and protein within 48–72 hrs to achieve the benefit of enteral nutrition over the first week of hospitalization
In Severely Malnourished or High Risk Patients, Hypocaloric Feeding (≤20 kcal/ kg/d or 80% of Estimated Energy Needs) with Adequate Protein (≥1.2 g protein/kg/day) Should Be Considered Over the First Week in the ICU (Quality of Evidence: Expert Consensus)
Site of Enteral Nutrition Delivery
Rationale
Changing the Level of Tube Feeding Infusion From the Stomach to the Small Bowel Decreases the Incidence of Regurgitation, Aspiration, and Pneumonia
Efficacy
Multi-Center Randomized Trial Comparing Nasogastric vs Nasojejunal Feeding (Crit Care Med, 2012) [MEDLINE]
No Difference in Mortality, Length of Stay, Nutrient Delivery, and Incidence of Pneumonia
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
In Most Critically Ill Patients, Gastric Tube Feeding is Acceptable (Quality of Evidence: Moderate-High): it is technically easier to use gastric feeding
In Patients at High Risk for Aspiration, Post-Pyloric Tube Feeding Should Be Used (Quality of Evidence: Moderate-High), Continuous Infusion Should Be Used (Quality of Evidence: Expert Consensus), and Promotility Agents (Metoclopramide, Erythromycin) Should Be Used (Quality of Evidence: Low)
Measures to Decrease Aspiration (Head of Bed 30°–45°, Chlorhexidine Mouthwash BID) Should Be Employed While Delivering Tube Feeds (Quality of Evidence: Expert Consensus)
Inadequate Delivery of Enteral Nutrition
General Comments
Patients are Commonly Underfed in the ICU
Study of “Best Achievable” Practice for Nutrition in the ICU (Crit Care Med, 2010) [MEDLINE]
Average Time to Start Enteral Nutrition in Study: 46.5 hrs
Average Nutritional Adequacy for Energy Needs: only 59%
Average Nutritional Adequacy for Protein Needs: only 60%
Reasons for Inadequate Delivery of Enteral Nutrition
Enteral Nutrition Intolerance: accounts for approximately 33% of cessation time
Technical Issues with Feeding Tube
Tube Feeding Cessation for Anticipated Diagnostic Testing/Procedures
Under-Prescription of Enteral Nutrition by Provider
Use of Prokinetic Agents
Clinical Efifcacy
Meta-Analysis and Systematic Review of Prokinetic Agents in Critically Ill Patients Receiving Enteral Nutrition (Crit Care, 2016) [MEDLINE]
Prokinetic Agents Decrease Feeding Intolerance in Critically Ill Patients, as Compared to Placebo or No Intervention
However, the Impact of Prokinetic Agents on Other Outcomes (Such as Pneumonia, Mortality, and ICU Length of Stay is Unclear
Recommendations-Probiotics (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
While Probiotics Appear to Be Safe in ICU Patients, They Should Only Be Used in Select Populations (Quality of Evidence: Low)
No Specific Recommendations are Made Regarding the Use of Probiotics
Complications/Adverse Effects of Enteral Nutrition
Not Monitoring Gastric Residual Volume Did Not Increase the Incidence of Aspiration or Related Complications
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Gastric Residual Volume Should Not Be Used to Monitor Enteral Nutrition (Quality of Evidence: Low): if used, cutoff for residual volume should be >500 mL
Tube Feedings Should Not Be Stopped Automatically for Diarrhea (Quality of Evidence: Expert Consensus)
Diarrhea Occurs in 15-18% of Patients on Enteral Nutrition, as Compared to 6% of Patients Who Have Not Received Enteral Nutrition (Crit Care Med, 1999) [MEDLINE] and (Nutrition, 2008) [MEDLINE]
Diarrhea May Result in Electrolyte Abnormalities, Dehydration, Perianal Skin Breakdown, Wound Contamination, etc
EDEN Trial of Enteral Nutrition in Acute Lung Injury (JAMA, 2012) [MEDLINE]
Initial Trophic Feeding (For Up to 6 Days) Did Not Improve Ventilator Days, 60-Day Mortality, or Infectious Complications, as Compared to Full Feeding
Full Feeding Group Had More Gastrointestinal Intolerance (Vomiting, Constipation, and Elevated Gastric Residual Volumes): full feeding group patients received more pro-kinetic agents
One Year Follow-Up of the ARDS Network EDEN Trial of Trophic vs Full Enteral Feeding in Acute Lung Injury (BMJ, 2013) [MEDLINE]
In Survivors of Acute Lung Injury, There was No Difference in Physical Function, Survival, or Multiple Secondary Outcomes at 6 or 12 mo After Initial Trophic vs Full Enteral Feeding
One Year Follow-Up of Physical and Cognitive Performance in the ARDS Network EDEN Trial of Trophic vs Full Enteral Feeding in Acute Lung Injury (Am J Respir Crit Care Med, 2013) [MEDLINE]
EDEN Trial Survivors Performed Below Predicted Values for Physical and Cognitive Performance at 6 and 12 mo with Some Improvement Over Time
Initial Trophic vs Full Enteral Feeding for the First 6 Days Did Not Impact Physical or Cognitive Outcomes
Permissive Underfeeding (40-60% of Calculated Caloric Requirement) vs Target (70-100% of Calculated Caloric Requirement) Enteral Feeding in Adult Critically Ill Patients (PermiT) Trial (NEJM, 2015) [MEDLINE]
Permissive Underfeeding Did Not Impact the 90-Day Mortality Rate, Feeding Intolerance, Incidence of Diarrhea, ICU-Acquired Infection Rate, ICU Length of Stay, or Hospital Length of Stay
Fiber: most commonly used (and studied) intervention for tube feeding-related diarrhea
Fiber Use in Patients on Vasopressors (Who Manifest Impaired Bowel Peristalsis) May Be Associated with an Increased Risk of Bezoar Formation (Nutrition, 1990) [MEDLINE]
Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]
Gastric Residual Volume Should Not Be Used to Monitor Enteral Nutrition (Quality of Evidence: Low): if used, cutoff for residual volume should be >500 mL
Tube Feedings Should Not Be Stopped Automatically for Diarrhea (Quality of Evidence: Expert Consensus)
Fermentable Soluble Fiber (Fructo-Oligossaccharides or Inulin; 10-20 g/day) is Suggested as an Additive in All Hemodynamically Stable MICU/SICU Patients on a Standard Enteral Formulation, if There is Evidence of Diarrhea (Quality of Evidence: Expert Consensus)
Hospitalized Patients Who Receive Tube Feedings are at Increased Risk for Clostridium Difficile, as Compared to Hospitalized Patients Who Do Not Receive Tube Feeding (Ann Intern Med, 1998) [MEDLINE]
Potential Preventative Measures: although it’s not clear that these measures actually decrease the risk of aspiration pneumonia (in particular, ventilator-associated pneumonia)
Elevation of the Head of the Bed
Percutaneous Gastrostomy (PEG) Tube Placement (see Gastrostomy): however, gastrostomy tubes have not been demonstrated to impact the rate of aspiration pneumonia or the mortality rate, as compared to nasogastric tubes (Cochrane Database Syst Rev, 2015) [MEDLINE]
Physiology: most tube feedings contain only 70-80% water, are mildly hypertonic, and are not adequate to meet the patient’s normal water requirements
Treatment: most patients require additional free water to meet water requirements (and for flushing of the feeding tube itself)
Other Complications/Adverse Effects
Overfeeding: with increased carbon dioxide production
Underfeeding: with prolonged ICU stay
References
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A randomized trial of glutamine and antioxidants in critically ill patients. N Engl J Med. 2013;368:1489–1497 [MEDLINE]
Early Parenteral Nutrition in Critically Ill Patients With Short-term Relative Contraindications to Early Enteral Nutrition. JAMA. 2013 May 22;309(20):2130-8. doi: 10.1001/jama.2013.5124 [MEDLINE]
Nasogastric or nasojejunal feeding in predicted severe acute pancreatitis: a meta-analysis. Crit Care. 2013;17(3):R118 [MEDLINE]
One year outcomes in patients with acute lung injury randomised to initial trophic or full enteral feeding: prospective follow-up of EDEN randomised trial. BMJ. 2013 Mar 19;346:f1532. doi: 10.1136/bmj.f1532 [MEDLINE]
Physical and cognitive performance of patients with acute lung injury 1 year after initial trophic versus full enteral feeding. EDEN trial follow-up. Am J Respir Crit Care Med. 2013;188(5):567-576 [MEDLINE]
CALORIES Trial. Trial of the Route of Early Nutritional Support in Critically Ill Adults. N Engl J Med. 2014 Oct 30;371(18):1673-84. doi: 10.1056/NEJMoa1409860. Epub 2014 Oct 1 [MEDLINE]
The Canadian Critical Care Nutrition Guidelines in 2013: an update on current recommendations and implementation strategies. Nutr Clin Pract. 2014;29:29–43. doi: 10.1177/0884533613510948 [MEDLINE]
Early versus on-demand nasoenteric tube feeding in acute pancreatitis. N Engl J Med. 2014;371(21):1983–1993 [MEDLINE]
Nutrition in the acute phase of critical illness. N Engl J Med. 2014 Mar 27;370(13):1227-36. doi: 10.1056/NEJMra1304623 [MEDLINE]
PermiT Trial. Permissive underfeeding or standard enteral feeding in critically ill adults. N Engl J Med. 2015;372(25): 2398–2408 [MEDLINE]
Percutaneous endoscopic gastrostomy versus nasogastric tube feeding for adults with swallowing disturbances. Cochrane Database Syst Rev. 2015 May 22;(5):CD008096. doi: 10.1002/14651858.CD008096.pub4 [MEDLINE]
The efficacy and safety of prokinetic agents in critically ill patients receiving enteral nutrition: a systematic review and meta-analysis of randomized trials. Crit Care. 2016 Aug 15;20(1):259. doi: 10.1186/s13054-016-1441-z [MEDLINE]
Enteral Nutrition in Patients Receiving Mechanical Ventilation in a Prone Position. JPEN J Parenter Enteral Nutr. 2016 Feb;40(2):250-5. doi: 10.1177/0148607114553232 [MEDLINE]
Guidelines for the Provision and Assessment of Nutrition Support Therapy in the Adult Critically Ill Patient: Society of Critical Care Medicine (SCCM) and American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.). JPEN J Parenter Enteral Nutr. 2016 Feb;40(2):159-211. doi: 10.1177/0148607115621863 [MEDLINE]
Nutrition in acute pancreatitis: a critical review. Expert Rev Gastroenterol Hepatol. 2016;10:571–580 [MEDLINE]
Early Versus Delayed Feeding in Patients With Acute Pancreatitis: A Systematic Review. Ann Intern Med. 2017 Jun 20;166(12):883-892. doi: 10.7326/M16-2533. Epub 2017 May 16 [MEDLINE]
TARGET Trial. Energy-Dense versus Routine Enteral Nutrition in the Critically Ill. N Engl J Med. 2018 Nov 8;379(19):1823-1834. doi: 10.1056/NEJMoa1811687 [MEDLINE]
