IV Pump Flow Rate Calculator
Calculate infusion rates in mL/hr and drip rates in gtt/min.
How to Use the IV Pump Flow Rate Calculator
In clinical settings, accurately calculating the intravenous (IV) flow rate is critical for patient safety and therapeutic efficacy. This calculator helps healthcare professionals determine the exact settings for an electronic infusion pump (mL/hr) or the manual gravity drip rate (gtt/min).
To use this tool, follow these steps:
- Total Volume: Enter the total amount of fluid to be infused in milliliters (mL).
- Time: Input the duration over which the fluid should be delivered. You can split this into hours and minutes.
- Drop Factor: This is determined by the administration set used. Standard macro-drip sets are usually 10, 15, or 20 gtt/mL, while micro-drip sets (often used in pediatrics) are 60 gtt/mL.
Essential Formulas for IV Calculation
The math behind IV therapy relies on two primary formulas:
1. Electronic Pump Rate (mL/hr):
Flow Rate (mL/hr) = Total Volume (mL) ÷ Total Time (Hours)
2. Manual Drip Rate (gtt/min):
Drip Rate (gtt/min) = [Total Volume (mL) × Drop Factor (gtt/mL)] ÷ Total Time (Minutes)
Practical Examples
Example 1: Normal Saline Infusion
A physician orders 1,000 mL of Normal Saline to be infused over 8 hours using a 15 gtt/mL administration set.
- Pump Rate: 1,000 mL ÷ 8 hours = 125 mL/hr
- Drip Rate: (1,000 mL × 15) ÷ 480 minutes = 31.25 (approx. 31 gtt/min)
Example 2: Antibiotic Piggyback
Administering 100 mL of an antibiotic over 30 minutes with a micro-drip set (60 gtt/mL).
- Pump Rate: 100 mL ÷ 0.5 hours = 200 mL/hr
- Drip Rate: (100 mL × 60) ÷ 30 minutes = 200 gtt/min
Common Drop Factors to Remember
The "Drop Factor" refers to how many drops it takes to make up 1 mL of fluid. This is always printed on the IV tubing packaging:
- 10 gtt/mL: Large drops (Macro-drip)
- 15 gtt/mL: Standard drops (Macro-drip)
- 20 gtt/mL: Standard drops (Macro-drip)
- 60 gtt/mL: Very small drops (Micro-drip), often used for precise medication delivery.