G Tube Feed Rate Calculator
Calculate infusion rates for continuous pump feeding or bolus volume requirements.
Understanding Your G Tube Feed Calculation
Ensuring accurate nutrition delivery via a Gastrostomy Tube (G-Tube) is critical for maintaining weight, hydration, and overall health. Whether you are managing enteral nutrition for yourself, a patient, or a loved one, calculating the correct feed rate prevents complications such as aspiration, vomiting, or malnutrition.
Continuous vs. Bolus Feeding
This calculator handles the two primary methods of tube feeding:
- Continuous Feeding: This method uses an enteral feeding pump to deliver formula slowly over a set period (usually 8 to 24 hours). The key metric here is the Flow Rate (ml/hr), which tells the pump how fast to push the fluid.
- Bolus Feeding: This mimics typical meal patterns. Larger volumes of formula are given over short periods (15–30 minutes) several times a day using a syringe or gravity bag. The calculation focuses on the Volume per Feed (ml).
How to Calculate the Rate
The math behind enteral feeding is straightforward but requires precision:
For Continuous Pumps:
Rate (ml/hr) = Total Daily Volume (ml) ÷ Hours of Feeding
For example, if a patient requires 1200ml of formula delivered over 20 hours: 1200 ÷ 20 = 60 ml/hr.
For Bolus Feeds:
Volume per Feed = Total Daily Volume (ml) ÷ Number of Feeds
If the prescription is 1500ml divided into 5 meals: 1500 ÷ 5 = 300 ml per feed.
Caloric Density Matters
Not all formulas are created equal. The caloric density refers to how much energy is in every milliliter of fluid.
- Standard: 1.0 kcal/ml (1000 calories per liter)
- Concentrated: 1.2 to 2.0 kcal/ml (used for fluid restrictions or high energy needs)
- Diluted: Less than 1.0 kcal/ml (rare, usually for hydration or tolerance issues)
Always verify the density on the formula carton label to ensure the patient is receiving the prescribed calorie count.
Safety Considerations
Always consult with a Registered Dietitian or physician before changing feed rates. Increasing a rate too quickly ("advancing the rate") can cause gastrointestinal distress. Standard practice often involves starting slow and increasing by 10-20 ml/hr every 4-8 hours until the goal rate is achieved.