[EnviroVeg]

A useful tutorial for learning about and practicing dosage calculations:
http://www.dosagehelp.com/

[Optimistic :>)]

Originally Posted by EnviroVeg

A useful tutorial for learning about and practicing dosage calculations:
http://www.dosagehelp.com/

Thank you for the tip on the dosage calculation tutorial; I have a dosage calc. exam coming up soon; and this website has a lot of useful practice questions.

[cperg51018]

1. A Phsycian orders an IV of D5W to run @ 100mlls
The drop factor is 10gtt/ml
What is the flow rate??
2. Tetracycline is prepared in 50ml of an IV solution it is infusing @ 30gtts/min.
The drop factor of the infusion set is 20gtts/ml. What is the infusion time?/

[Daytonite]

Originally Posted by cperg51018

1. A Physician orders an IV of D5W to run at 100 mL (per 60 minutes?). The drop factor of the IV tubing is 10 gtts/mL. What is the flow rate?

100 mL/60 minutes (amount to give) x 10 gtts/1 mL (drop factor of IV tubing) = 16.66 gtts/minute, rounded off to 17 gtts/minute (a drop must be a whole number)

Originally Posted by cperg51018

2. Tetracycline is prepared in 50 mL of an IV solution. It is infusing at 30 gtts/minute. The drop factor of the infusion set is 20 gtts/mL. What is the infusion time?

1 minute/30 gtts (infusion rate) x 50 mL/1 (amount to give) x 20 gtts/1 mL (drop factor of IV tubing) = 33.33 minutes

[cperg51018]

Thank you for your help in the calculation if medication through IV, I am studying to be a CMA certified medical assistant and I am in phlebotomy now and we are into the calcultaions, Is there any way of breaking these calculations down to help understand them better?

[Daytonite]

Do many problems. Read the problem carefully and pick out the terms that are in this formula: Dose desired divided by dose on handed multiplied by the amount the dose on hand is in equals the amount to give. Make sure you read the final line of the problem and you understand exactly what the problem is asking you to find. For IV problems you may need to factor in the drops/mL of the IV tubing to get the rate/hour. Apply conversion factors as needed.

There are medication calculation tutorials on post #3 of this thread:

• http://allnurses.com/forums/f50/nursing-math-thread-264395.html - The Nursing Math Thread (in the General Nursing Student Discussion Forum)

and you can see lots of problems that have been worked out on this thread if you go back through the posts.

[pycho24]

Someone Please Help!!!

I am currently taking Dosage. I have been having a hard time with these questions trying to figure out the formulas but dont seem to understand how to do them. If anyone could help that would be great. I will post a few at the bottom please let me know.

A nipride drip is ordered to infuse on a pump at 2mcg/Kg/min on a patient weighting 110lbs. Nipride is supplied 50mg/250ml D5W. how many ml/h will the IV need to run?

A dopamine drip is ordered to infuse at 3mcg/Kg/min. The solution is avaliable in 400mg in 250ml D5W. The patient weights 155lbs. using a 60gtt/ml set:
What is the mcg/min dosage?
What is the gtt/min flow rate?

An order of 250mg in 5ml is to be diluted to a total of 50ml and given over 70min. How much dilutent should be used? and what is the ml/hr rate?


I appreciate any feedback that I get. Thanks

[Daytonite]

Originally Posted by pycho24

A nipride drip is ordered to infuse on a pump at 2mcg/Kg/min on a patient weighting 110lbs. Nipride is supplied 50mg/250ml D5W. how many ml/h will the IV need to run?

2 mcg/1 kg (dose desired) x 110 pounds/ 1 minute (patients weight/time dose desired to infuse) x 250 mL/50 mg (dose on hand) x 1 kg/2.2 pounds (conversion factor) x 60 minutes/1 hour (conversion factor) x 1 mg/1000 mcg (conversion factor) = 30 mL/hour (amount to give)

Originally Posted by pycho24

A dopamine drip is ordered to infuse at 3mcg/Kg/min. The solution is available in 400mg in 250ml D5W. The patient weights 155lbs. using a 60gtt/ml set:

Originally Posted by pycho24

What is the mcg/min dosage?
What is the gtt/min flow rate?

3 mcg/1 kg (dose desired) x 155 pounds/ 1 minute (patients weight/time dose desired to infuse) x 1 kg/2.2 pounds (conversion factor) = 211.36363 mcg/min, rounded off to 211 mcg/min (amount to give)

211 mcg/1 minute (dose desired) x 250 mL/400 mg (dose on hand) x 60 gtts/1 mL (drip factor of IV tubing) x 1 mg/1000 mcg (conversion factor) = 7.9125 drops/minute, rounded off to 8 gtts/minute (flow rate)

Originally Posted by pycho24

An order of 250mg in 5ml is to be diluted to a total of 50ml and given over 70min. How much diluent should be used? and what is the ml/hr rate?

50 mL - 5 mL = 45 mL (amount of diluent to use)

50 mL/70 minutes (dose to give) x 60 minutes/1 hour (conversion factor) = 42.857142 mL/hour, rounded off to 43 mL/hour (infusion rate)

[pycho24]

Hey can I ask for your help on two more?

The order is to infuse 500mg in 250ml at a rate of 8ml/h. Calculate the mg/h? And what are the mcg/min being recieved?

A heparin drip was ordered to infuse at 1250units/h. The solution strength is 20,000units in 500ml D5W. A pump is used to monitor the rate. Calculate the flow.

Thanks

[Daytonite]

Originally Posted by pycho24

The order is to infuse 500 mg in 250 mL at a rate of 8 mL/hour. Calculate the mg/hour. What are the mcg/minute being received?

This is similar to the last problem you asked about. . .
500 mg/250 mL (dose on hand) x 8 mL/hour (infusion rate) = 16 mg/hour (dose being given)

16 mg/hour x 1000 mcg/1 mg (conversion factor) x 1 hour/60 minutes (conversion factor) = 266.666 mcg/minute, rounded off to 267 mcg/minute

Originally Posted by pycho24

A heparin drip was ordered to infuse at 1250 units/hour. The solution strength is 20,000 units in 500 mL of D5W. A pump is used to monitor the rate. Calculate the flow.

Pumps are always set at mLs per hour.

1,250 units/hour (dose desired) x 500 mL/20,000 units (dose on hand) = 31.25 mL/hour which must be rounded off to 31 mL/hour (rate to set the IV pump at)