IV Drug calculation
mL/hr = rate
ignore mg
Ratio and proportion method
H: V :: D: X
Known :: Unknown
How to solve the ratio and proportion methods
- Multiply the outer most numbers
- Multiply the inner most numbers
- Solve for x
The ratio proportion method can be used to solve minutes of infusion equations by using
Known drug: known minutes:: desired drug : desired minutes
1 g= ____ mg
1000 mg
1 mg =__ mcg
1000 mcg
Fractional equation method
H/v = d/x
Fractional equation method
Dosage on hand/ solution on hand = desired dosage/ x
X= desired amount
How to solve IV medications ordered per minute
- Figure out dosage flow rate
2. Calculate hourly flow rate
IV medications ordered per minute (more detailed how to)
- Dosage on hand/ solution on hand =
dosage desired/ min (ordered)/ X (desired amount) - mL/min X 60 min/hour = mL/ hour
IV medications ordered per kg per minute
- Convert
Mg-> mcg
lb-> kg - Calculate desired mcg/ min
- Calculate mL/min
- Calculate mL/ hr
IV medications per kg per minute (more detailed)
- Convert
1mg= 1000 mcg
1 kg=2.2 lbs - Find mcg/ min
Use given mcg/kg/min X patients kg = mcg/ min - calculate mL/ min
H/v X d/X - Calculate mL/ hr
mL/min X 60min/ hr= ____mL/hr
IV flow rate 3 step method
- Amount of solution/ hours to administer = mL/hr
- mL per hour/ 60 minutes = mL/min
- mL per minute X gtt per mL of IV set = gtt/ min
1 L = __ mL
1000 mL
gtt/ min used in adults
60 gtt/min
To calculate how long an infusion will last
Total volume of the bag/ ml per hour = _____ hours
Example: 1000mL/ 100mL per hour = 10 hours
