GTT Dosage Calculations
1000 mL LR to infuse in 10 hr. Drop factor: 20 gtt/mL
Answer 33 gtt/min gtt/min= 20 gtt/mL x 1000mL/10hr x 1hr/60min= 20gtt x 1000mL x 1 hr= 20000 1mL x 10hr x 60 min= 600 20000/600= 33.33 (round to whole #) 33 gtt/min
A unit of packed cells (250mL) to infuse in 4 hr. Drop factor: 20gtt/min
Answer: 21 gtt/min gtt/min= 20gtt/mL x 250mL/4hr x 1hr/60min= 20gtt x 250mL x 1 hr= 5000 1mL x 4 hr x 60 min= 240 5000/240= 20.833 (round to whole #) 21 gtt/min
2L D5LR @ 150 mL/hr. Drop factor: 15gtt/mL
Answer: 38 gtt/min gtt/min= 15gtt/mL x 150ml/hr x 1hr/60min= 15gtt x 150mL x 1 hr= 2250 1mL x 1hr x 60min= 60 2250/60= 37.5 (round to whole #) 38 gtt/min
Calculate the IV flow rate in gtt/min for the following administrations, unless another unit of measure is stated. 1000 mL D5LR to infuse in 8 hr. Drop factor: 20 gtt/mL. How many gtt/min?
Answer: 42 gtt/min gtt/min= 20gtt/mL x 1000mL/8hr x 1hr/60min= 20gtt x 1000mL x 1hr= 20000 1mL x 8hr x 60min= 480 20000/480= 41.67 (round to whole #) 42 gtt/min
An IV of D5W 1000mL was ordered to infuse over 8 hr at a rate of 42 gtt/min (42 macrogtt/min). Drop factor: 20 gtt/mL. After 4 hr. you notice that only 400 mL has infused. Recalculate the rate in gtt/min for the remaining solution.
Answer: 50 gtt/min gtt/min= 1000mL (what was started) -400mL (what is left)= 600mL 8 hr-4hr= 4hr 20gtt/mL x 600mL/4hr x 1hr/60min= 20gtt x 600mL x 1hr=12000 1mL x 4hr x 60min= 240 12000/240= 50gtt/min 50 gtt/min
Infuse 3000 mL D5W in 20 hr. Drop factor: 20gtt/mL
Answer: 50 gtt/min gtt/min= 20gtt/mL x 3000mL/20hr x 1 hr/60min= 20gtt x 3000mL x 1hr= 60000 1mL x 20hr x 60min= 1200 60000/1200= 50 50gtt/min
1000mL of D5W is infusing @ 20 gtt/min (20 macrogtt/min). Drop factor: 10gtt/mL. How long will it take for the IV to infuse? (Express in hours & minutes.)
Answer: 8 hr. 20 min. hr/min= 1hr/60min x 1min/20gtt x 10gtt/mL x 1000mL/?= 1hr x 1min x 10gtt x 1000mL= 10000 60min x 20gtt x 1mL x ?= 1200 10000/1200= 8.33 8hr and 0.33 min 0.33 x 60min= 19.80 (round off to 20) 8 hrs and 20 min.
An IV is @ 25 gtt/min (25 macrogtt/min). Drop factor: 15 gtt/mL. How many mL of fluid will the client receive in 8 hr?
Answer: 800 mL mL= mL/15gtt x 25gtt/min x 60min/hr x 8hr/?= mL x 25gtt x 60 x 8hr= 12000 15gtt x 1 min x 1 hr x ?= 15 12000/15= 800mL 800mL
