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Try this formula.......volume to be infused X the drip factor
-------------------------------------------------
time in min
so get your top value and divide it by the time in min
here is a fast way to get the answer for tests ..divide the cc per hr by either 6 (drip factor of 10) 5 (for a drip factor of 12).....4 (for a drip factor of 15) and 3 (for a drip factor of 20)..... so in your case 100 divided by 6 is egual to 16.66 and round it up to 17
So now work it out both ways and practice
Formula:
[TABLE=class: formula]
[TR]
[TD]
[TABLE=class: fraction]
[TR]
[TD=class: numerator]Volume (mL)
[/TD]
[/TR]
[TR]
[TD=class: denominator]Time (min)
[/TD]
[/TR]
[/TABLE]
[/TD]
[TD] x Drop Factor (gtts/mL) = Y (Flow Rate in gtts/min)
[/TD]
[/TR]
[/TABLE]
Example: Calculate the IV flow rate for 1200 mLof NS to be infused in 6 hours. The infusion set is calibrated for a drop factor of 15 gtts/mL.[TABLE=class: example]
[TR]
[TD]
[TABLE=class: fraction]
[TR]
[TD=class: numerator]Volume (mL)
[/TD]
[/TR]
[TR]
[TD=class: denominator]Time (min)
[/TD]
[/TR]
[/TABLE]
[/TD]
[TD] x Drop Factor (gtts/mL) = Y (Flow Rate in gtts/min)
[/TD]
[/TR]
[/TABLE]
Convert 6 hours to minutes.
[TABLE=class: example]
[TR]
[TD]
[TABLE=class: fraction]
[TR]
[TD=class: numerator]1200 mL
[/TD]
[/TR]
[TR]
[TD=class: denominator]360 min
[/TD]
[/TR]
[/TABLE]
[/TD]
[TD] x 15 gtts/mL = 50 gtts/min
[/TD]
[/TR]
[/TABLE]
Example: Calculate the IV flow rate for 200 mLof 0.9% NaCl IV over 120 minutes. Infusion set has drop factor of 20 gtts/mL.[TABLE=class: example]
[TR]
[TD]
[TABLE=class: fraction]
[TR]
[TD=class: numerator]Volume (mL)
[/TD]
[/TR]
[TR]
[TD=class: denominator]Time (min)
[/TD]
[/TR]
[/TABLE]
[/TD]
[TD] x Drop Factor (gtts/mL) = Y (Flow Rate in gtts/min)
[/TD]
[/TR]
[/TABLE]
[TABLE=class: example]
[TR]
[TD]
[TABLE=class: fraction]
[TR]
[TD=class: numerator]200 mL
[/TD]
[/TR]
[TR]
[TD=class: denominator]120 min
[/TD]
[/TR]
[/TABLE]
[/TD]
[TD] x 20 gtts/mL = 33 gtts/min
[/TD]
[/TR]
[/TABLE]
Go here for more help....it's a great site. This website provides a dosage calculations tutorial, complete with explanations and examples, to help nursing students prepare for a medication exam.
16.66666666666666666666666666666666666666666666666666 is what I came up with.
Pretty easy.
Since you're looking for a per minute rate and the order is per hour, first find how many mL are to be administered per minute.
100ml/hr divided by 60 minutes = 1.66666666666666666mL/min
Then multiply your drip factor (drops/mL) by the number of mL/min.
(10gtt/mL) x (1.66666666666mL/min) = 16.66666666666666666
The mL's cancel out and you're left with gtt/min.
LCinTraining
308 Posts
I've done this problem ten different ways and keep coming up with 5.5 drops/min, but the answer is 17 gtts/min when I check my answer with the answer code. Any help is appreciated...The order is for D5W at 100 mL/hr. The drop factor is 10 gtts/mL. Calculate the flow rate in drops/minute.I've tried various dimensional analysis set ups, but 5.5 is what I get. I'm starting to think I'm missing a conversion factor that I can't seem to remember or something.