IV Infusion Time Calculator: Pump or No Pump

Formulas

Use the basic time formula with an IV pump to calculate hours.

V R
  • V = Volume
  • R = Rate

Drops/minute (gtt/min) must be converted into hours when using calibrated tubing without a pump.

V × C ( G × 60 min )
  • V = Volume
  • C = IV tubing calibration
  • G = gtt/min

Examples

1. Using a volumetric IV pump calculate to duration of 1000 milliliters (mL) of normal saline infusing at 125 milliliters/hour (mL/hr).

  • Volume = 1000 mL
  • Rate = 125 mL
1000 mL 125 mL

The answer is 8 hours.

2. There are 250 mL of D5W infusing at 33 (gtt/min) on IV tubing calibrated at 10 drops/milliliter (gtt/mL).  Calculate the infusion time.

  • Volume = 250 mL
  • IV tubing calibration = 10 gtt/mL
  • gtt/min = 33 gtt/min
250 mL × 10 ( 33 × 60 min )

The answer is 1.26 hours.

Convert partial hours into minutes.

P × 60 min

  • P = Partial hours
  • Partial hours = 0.26

0.26 × 60 min

0.26 hours = 15.7 minutes. Round 15.7 to 16. The answer to the second question is 1 hour and 16 minutes.