Dosage calculation help

[ThereisStillHope]

1. Order: 250 ml NS to infuse at 50 ml/hr – started at 9 a.m. (60 gtts/ml).
   

How many drops perminute?

At what time of day will the NS haveinfused?

So I have the second part figured out...1400 but I am having problems with the first part. This is my work. Could someone show me where I went wrong please?

250 ml x 60 gtts

50 ml/hr

So I multiplied the top and divided by the bottom to come up with the answer of 18000 gtts/min. I did convert it to minutes separately, which was .83, when I did the problem again and came up with 18072.3 gtts/min. This just seems like an outrageous answer and was confused on how else to set this up, as this is the way our instructor taught us. If there is something easier to understand, send it my way please! Thank you to any one who helps!

[NICU Guy, BSN, RN]

You know that you are infusing at 50 mL/hr, so you can calculate mL/min. You also know ggts/mL. You should be able to insert ggts/ml once you know mL/min.

Here is an example to help you out: If you are infusing at 120 mL/hr and 60 ggts/mL.

120 mL/60 min= 2mL/min.

60 ggts/ mL X 2 mL/min.= 120 ggts/ min.

or

120 mL/hr X 60 ggts/mL= 7200 ggts/ hr.

7200 ggts/ 60 min= 120 ggts/ min

The amount to infuse is a distractor.

[bgxyrnf, MSN, RN]

250 ml x 60 gtts

50 ml/hr

Here's your fundamental problem: The units of measure for the drip factor IS NOT gtt... IT IS gtt/mL.

The problem is asking you for a drip rate... drops per unit of time.

The problem provides you pieces of information... Volume, drops per unit volume, and volumetric rate (volume per unit of time)

So if you know the volume per unit of time and you know the relationship between drops and volume then you need only convert the volumetric rate to the drip rate by directly converting from volume to the number of drops that make up that volume.

In one hour, 50 mL will have been infused... how many drops is that? (Think drip factor... drops per mL... 1 mL = 60 gtt, 2 mL = 120 gtt, 3 mL = 180 gtt... etc, etc... 50 mL = ? gtt)

Now you know how many drops in an hour... that is, the drip rate per hour

The question wants the drip rate per minute, though.

Easy enough... convert the hourly rate to a minute rate with the simple equation 60 min = 1 h