II. Physiology: Enteral Nutrition Benefits
- Enteral Nutrition is preferred (even in intubated patients)
- Gastrointestinal integrity is maintained with enteral feedings
- Decreased risk of Gram Negative bacteremia from translocation
- Decreases Malnutrition
- Decreases Stress Ulcer risk
- Decreases ileus risk
III. Contraindications: Enteral Nutrition
- Bowel perforation
- Complete Small Bowel Obstruction
- Upper Gastrointestinal Hemorrhage
- Mesenteric Ischemia
- Circulatory shock requiring high dose Vasopressors
- Pancreatitis is NOT a contraindication to enteral feeding
- Absent bowel sounds in ICU patients is NOT a contraindication to enteral feeding
IV. Types: Delivery
- Short-term Feeding Tubes
- Orogastric Tube
- Typically used in intubated patients
- Nasogastric Tube
- Most commonly used as is physiologic and allows for large volume bolus feedings
- Smaller caliber nasal Feeding Tube (post-intubation)
- Smaller caliber does not allow for gastric suctioning
- Can be left in place longer than larger bore tubes
- Nasoduodenal Tube (post-pyloric Feeding Tube)
- Indicated if higher Aspiration Pneumonia risk, gastric dysmotility or obstruction
- Requires continuous delivery device
- Orogastric Tube
-
Enterostomy Tube
- Indicated for anticipated enteral feeding beyond 4 weeks
- Sub-types
- G-Tube: Gastrostomy or Gastric Tube
- Medication delivery
- Feedings may be drip or bolus
- GJ-Tube: Combined tube with both Gastric and Jejunal ports
- Medication delivery or bolus feeds via gastric port
- Drip feeds via jejunal port
- J-Tube: Jejunostomy or Jejunal Tube
- Requires drip feeds
- Bolus feeds result in Osmotic Diarrhea
- G-Tube: Gastrostomy or Gastric Tube
V. Preparations
- See Enteral Nutrition
- Obtain nutrition Consultation
- Standard solution: 1 kcal/ml (e.g. Osmolite, Isocal, Replete)
- Renal Failure: 2 kcal/ml of renal preparation (e.g. Novasource Renal)
VI. Technique
- Confirm Feeding Tube placement on XRay before first use
- Feeding Tubes may be misplaced into airway and lungs with catastrophic results if used
- Start Tube Feeding early (within first 24-48 hours of ICU admission)
- Consider starting with small volumes (10-20 ml/h) and advance to target over 6-8 hours
- Start regardless of presence of bowel sounds (see above) unless other contraindications
- Typical target rate: 1 ml/hour/kg (based on Ideal Body Weight if obese)
- Renal Failure rate: 0.5 ml/hour/kg of the concentrated 2 kcal/ml formula
- Subtract Propofol (1 kcal/ml) rate from the target rate
- Avoid holding feeding aside from procedures or intolerance (e.g. Abdominal Distention, Vomiting)
- Gastric Residual Volumes do NOT need to be obtained and should not result in held feedings
- However, large Residual Volumes >500 ml may be of concern (see aspiration risk reduction below)
- Poulard (2010) JPEN J Parenter Enteral Nutr 34(2):125-30 +PMID:19861528 [PubMed]
- Reignier (2013) JAMA 309(3):249-56 +PMID:23321763 [PubMed]
VII. Complications: Obstructed or Clogged Feeding Tube
- Attempt to flush tube with warm water (effective in 30% of cases)
- Alternate aspirating and injecting may help to dislodge obstruction
- Instill Pancreatic Enzymes (effective in 75% of cases)
- Dissolve 1 tablet Viokase and 1 tablet Sodium carbonate 324 mg in 5 ml water
- Inject solution into Feeding Tube and clamp for 5 minutes
- Last, instill warm water flush
- Fogarty catheter technique
- Obtain Informed Consent
- Technique increases Feeding Tube pressure and may result in perforation, leak or tube aneurysm
- Obtain proper Fogarty catheter size (#4 for 10 to 12F Feeding Tubes, #5 for 14F Feeding Tubes)
- Estimate the length of the indwelling Feeding Tube and mark the Fogarty catheter at this length
- Insert the Fogarty catheter to the end of the estimated Feeding Tube length (marked distance)
- As resistance is met, inflate and deflate the Fogarty balloon and attempt to advance further
- Repeat as needed until estimated end of Feeding Tube is reached
- Inflate and deflate the Fogarty balloon one last time at the end of the Feeding Tube
- Withdraw the Fogarty catheter, stopping periodically to inflate and deflate the balloon
- Confirm clearance and tube integrity with KUB XRay after instilling 20-30 ml contrast via tube
- References
- Warrington (2022) Crit Dec Emerg Med 36(8):20
- Obtain Informed Consent
- Attempt to carefully pass flexible wire or drum cartridge catheter down tube
- Replace persistently clogged tubes
VIII. Complications: Aspiration Pneumonia
- Consider aspiration mitigation strategies if signs of regurgitation, Vomiting, or very high Residual Volumes (>500 ml)
- Raise head of bed to 45 degrees
- Advance Feeding Tube into Small Bowel (post-pyloric)
- Consider short-term prokinetic use in Gastroparesis (marginal efficacy that wanes to ineffective over days)
- Avoid these agents in Bowel Obstruction
- Erythromycin 200 mg IV every 12 hours
- Risk of promoting Antibiotic Resistance
- Consider starting with Erythromycin and adding Metoclopramide in 24 hours if needed
- Metoclopramide (Reglan) 10 mg IV every 6 hours
- More effective when used in combination with Erythromycin
- Naloxone 8 mg via Nasogastric Tube every 8 hours
- May improve gastric emptying if due to Opioid induced Gastroparesis
IX. Complications: Diarrhea
X. Complications: General
- Nasogastric or Nasoduodenal Tube Intolerance (nasal discomfort, gagging)
- Tube malfunction, obstruction or migration
- Nausea or Vomiting
- Abdominal cramping, Diarrhea
- Higher risk with hyperosmolar medications (e.g. Acetaminophen, Potassium), Sorbitol (>15 g/day)
- Dilute liquid medications with 10-30 ml water
- Gastrointestinal Bleeding
- Bowel Obstruction
- Provocation of Gastroesophageal Reflux
- Increased skin moisture and maceration
- Agitation with a greater need for restraints
-
Hyperglycemia
- Be aware of the high sugar content in liquid medications
XI. Prevention: Complication avoidance with nasogastric and nasoduodenal Feeding Tubes
- Periodic confirmation of Feeding Tube (depth marker, Xray)
- Flush Feeding Tube with 30 ml water every 4 hours
- Medications
- Flush Feeding Tube with 10 ml water after each medication instillation
- Avoid mixing medications before instilling (risk of medication precipitation and obstruction)
- Liquid medications are preferred when available
- However, avoid thick suspensions (e.g. Ciprofloxacin suspension) due to risk of tube plugging
- Medication delivery options
- Intravenous medication forms given via Enteral Tube
- Crush tablets or open capsules and dissolve in water (NOT sustained release medications)
- Hold tube feeds for 30-60 minutes before and after medications that require an empty Stomach
- Monitor levels of medications with narrow therapeutic range
- References
- (2023) Presc Lett 30(3):17-8
XII. Resources
- EMedicine G-Tube Replacement
- Internet Book of Critical Care (EM-Crit, Farkas)
XIII. References
- Majoewsky (2012) EM:Rap 2(9): 7
- Marino (2014) The ICU Book, p. 859-73
- Finucane (1999) JAMA 282:1368 [PubMed]
- Li (2002) Am Fam Physician 65(8):1605-10 [PubMed]