yet another student asking for dosage calculation help...

  1. Okay we just switched theory instructors. Up until now the dosage calculations we have had on tests were fairly easy. No that I have the instructor who teaches the math for meds class, her questions seem to be more difficult for me. Here is a couple I am having trouble with...

    Ordered: IV insulin drip of 100U/100mL @0.7 u/kg
    Pt weighs: 150 lbs
    How much insulin is the pt getting per hour? Calculate both U/hr and ml/hr
    Okay I can change the weight, and I get the u/hr ( 47.6 U/hr) but I am stuck on how to get ml/hr the way is worded is tripping me up I think.

    Here is another:
    Ordered: 0.9% NaCl IV @ 125 mL/hr
    How many g/hr of NaCl will pt receive?
    I am totally lost on that on.

    Finally my last question:
    Ordered 25 mg of drug diluted in 8 mL NS IVP over 3 min
    How many mg will be infused in 30 sec?
    Is the answer 4.15 mg?

    Any help would be greatly appreciated!
  2. 1 Comments

  3. by   suzanne4
    100 units are in 1 ml, so just continue to the next step and divide the answer that you have by 100, and you will have what you are looking for.

    When you are given a percentage of something, how are you going to find out what it is equivalent to?? Example, if you have 5% Dextrose, then you have 5 grams of Glucose or Dextrose in 100 ml of solution. So if you have 0.9% Sodium Chloride, then you have 900 mg in 100 ml. You want to know how much you will be giving if you have to give 125 ml per hour. Just do the math................

    Yes.............but it also depends on what the drug was that you were diluting. Some will actually increase the final number, example if you dilute some antibiotics, you will actually have a final amount of 10 ml, not the 8 ml that you used as the diluent.

    Hope that this helps.....................