What volume of tube feeding (RT feeding) should be administered?

Volume of Tube Feeding Administration

Start continuous nasogastric tube feeding at 10–20 mL/hour using standard 1 kcal/mL formula, then advance by 10–20 mL increments every 8–12 hours based on tolerance, targeting 73–88 mL/hour (approximately 1750–2100 mL/day) for a typical 70 kg adult to meet 25–30 kcal/kg/day energy requirements. 1

Initial Starting Rate

• Begin continuous feeding at 10–20 mL/hour for adults using standard 1 kcal/mL formula 1
• For severely malnourished patients or those at risk of refeeding syndrome, start at the lower end (10 mL/hour) and advance more cautiously 1
• Post-surgical patients should initiate feeding within 24 hours at 10–20 mL/hour, which reduces infections and shortens hospital stay 1

Advancement Protocol

• Increase rate by 10–20 mL every 8–12 hours based on tolerance 1
• Reaching target intake typically requires 5–7 days due to limited intestinal tolerance—do not rush advancement 1
• For severely malnourished patients, allow 7–10 days to reach target rates 1

Target Volume Calculations

Energy Requirements

• Calculate total daily energy needs at 25–30 kcal/kg ideal body weight per day 1
• For a 70 kg patient: 1750–2100 kcal/day 1
• Using standard 1 kcal/mL formula, the goal rate is approximately 73–88 mL/hour for continuous feeding 1
• Minimum safe threshold: 1500 kcal/day (approximately 63 mL/hour continuous) to ensure adequate micronutrient provision 1

Protein Requirements

• Target 1.2–1.6 g/kg/day depending on nutritional status 1
• For a 70 kg patient: 84–112 g protein/day 1

Monitoring During Advancement

• Check gastric residual volumes every 4 hours initially 1
• If residuals exceed 200 mL, hold advancement and reassess 1
• Assess for feeding intolerance signs: abdominal distension, nausea, vomiting, diarrhea 1
• Position patient at ≥30° elevation during feeding and for 30 minutes after to minimize aspiration risk 1

Bolus Feeding Alternative (Gastric Access Only)

• Bolus feeding requires division of total feed volume into 4–6 feeds throughout the day 2
• Infusion volume typically 200–400 mL administered over 15–60 minutes per feeding 2
• Bolus feeding into the stomach is more physiological and does not predispose to diarrhea, bloating, or aspiration compared to continuous feeding 2
• Use bolus method only for nasogastric or gastrostomy tubes, never for jejunal feeding 2

Volume-Based Feeding Strategy (Advanced Approach)

• Establish a 24-hour goal volume rather than fixed hourly rate 3, 4
• Adjust infusion rate to compensate for interruptions and achieve daily goal 3, 4
• Volume-based feeding delivers 92.9% of goal calories versus 80.9% with traditional rate-based feeding 4
• On interrupted feeding days, volume-based patients receive 77.6% of goal calories versus 61.5% with rate-based feeding 4
• This approach safely increases energy delivery by 13.4% and protein delivery by 8.4% without increasing feed intolerance 5

Pediatric Volumes

• Infants (0–1 year): Start 10–20 mL/h or 1–2 mL/kg/h, target 21–54 mL/h or 6 mL/kg/h 1
• Children (1–6 years): Start 20–30 mL/h or 2–3 mL/kg/h, target 71–92 mL/h or 4–5 mL/kg/h 1
• Adolescents (6–14 years): Start 30–40 mL/h or 1 mL/kg/h, target 108–130 mL/h or 3–4 mL/kg/h 1
• Advance by 5–10 mL every 8 hours in pediatric patients 1
• In newborns with intestinal failure, expressed breast milk should be given continuously over 4–24 hour periods via feeding tube using volumetric pump 2

Overnight Feeding Option

• Overnight pump-assisted feeding allows daytime activity and uninterrupted sleep 2
• Patients avoid need to adjust flow rates during the night 2
• Combination methods (overnight continuous + daytime bolus) provide autonomy while meeting nutritional needs 2

Critical Pitfalls to Avoid

• Never dilute commercial formulas—this increases infection risk and creates osmolality problems 1
• Do not delay feeding initiation—delayed nutritional support increases complications, prolongs hospital stay, and increases mortality 1
• Avoid overfeeding in the acute phase—match energy to expenditure only after day 4–7, not immediately 1
• Never rely on auscultation alone for tube position verification—always obtain radiographic confirmation before initiating feeding 6

Tube Maintenance

• Flush feeding tubes with water every 4 hours during continuous feedings, after intermittent feedings, after medications, and after checking gastric residuals 7
• Routine water flushing before and after feeding prevents tube obstruction 2