TPN Infusion Rate Calculator
10 (Macro-drip)
15 (Macro-drip)
20 (Standard)
60 (Micro-drip)
Calculation Results
Infusion Pump Rate: 0 mL/hr
Gravity Drip Rate: 0 gtt/min
How to Calculate TPN Infusion Rate
Total Parenteral Nutrition (TPN) is a complex intravenous solution designed to provide a patient's complete daily nutritional requirements. Calculating the correct infusion rate is critical for patient safety, preventing metabolic complications like hyperglycemia or fluid overload.
The Basic TPN Rate Formula
In most clinical settings, TPN is delivered via an infusion pump. To find the hourly rate, use the following formula:
Infusion Rate (mL/hr) = Total Volume (mL) ÷ Total Time (hours)
Step-by-Step Example
Suppose a physician orders 2,400 mL of TPN to be infused over a 24-hour period. To calculate the rate:
- Identify Total Volume: 2,400 mL
- Identify Duration: 24 hours
- Calculate: 2,400 / 24 = 100 mL/hr
Calculating the Drip Rate (Gravity)
If an infusion pump is unavailable, you must calculate the drops per minute (gtt/min) using the drop factor of the IV tubing:
Drip Rate (gtt/min) = [Total Volume (mL) × Drop Factor (gtt/mL)] ÷ Total Time (minutes)
Important Clinical Considerations
- Tapering: Many TPN protocols require "tapering up" at the start and "tapering down" at the end to allow the pancreas to adjust insulin production.
- Cyclic TPN: Some patients receive their total nutrition over 12 or 16 hours instead of 24. Always verify the duration ordered.
- Verification: TPN rates should always be double-checked by two licensed clinicians due to the high risk of electrolyte imbalances.