heparin 100,000 units is added to 1 l d5w for post-streptokinase therapy. the rate of the iv is 80 mcgtt per minute. how much of the heparin is the client receiving each hour?
the amount of heparin the client is receiving each hours is the dose desired. if you plug this into the dose desired divided by dose on hand formula, you end up with this:
dose desired / 100,000 units/1 liter (dose on hand) = 80 mcgtts/1 minute (rate of infusion).
now, do some mathematical manipulation and isolate the dose desired by itself on one side of the equation and get all the other terms on the other side, such:
dd = 80 mcgtts/1 minute x 100,000 units/l liter
now, complete the problem by dimensional analysis in order to end up with a fraction for an answer whose final labels are units/hour
. here's what it will look like:
80 mcgtts/1 minute (rate of infusion) x 100,000 units/1 liter (dose on hand)x 60 minutes/1 hour (conversion factor) x 1 ml/60 mcgtts (conversion factor) x 1 liter/1000 ml (conversion factor) = 8,000 units/hour
you are to give dopamine 8 mcg/kg/min for renal perfusion. the dopamine is mixed 800 mg in 500 ml of d5w. the pt weighs 80 kg. how many mls per hour do you give?
very simply set this up by the dose desired divided by the dose on hand formula to get the dose to give. what you will end up is a complex fraction (a fraction divided by another fraction) where you will have to do mathematical manipulation to clear the denominators of fractions. once that is done, the final problem of dimensional analysis terms will look like this:
8 mcg/1 kg (dose desired) x 1/1 minute (time desired) x 500 ml/800 mg (dose on hand) x 1 mg/1000 mcg (conversion factor) x 60 minutes/1 hour (conversion factor) x 80 kg (patient's weight)= 24 ml/hour
pentamide 10 mg/kg/day for 14 days is recommended for a client with aids and pneumocystis pneumonia. a dose of 640 mg/100 ml d5w is being administered daily. for a client weighing 176 lbs, how many mg/kg/day is being administered?
this one is actually a lot simplier than you would think. it can be worked by doing a simple ratio. if the dose for a patient weighing 1kg is 10mg, then the dose for a patient weighing 176 pounds, or x kg would be _____, what? determine that 176 pounds is 80 kg
. 1kg = 2.2 pounds (conversion factor), so 176 pounds divided by 2.2 = 80 kg. now, set up an equivalency ratio:
10 mg of pentamide/1 kg of body weight = x mg of pentamide/80 kg of body weight
. cross multiple to get this: x = 800
. plug 800 into the equation for "x" and your answer is 800 mg