Cephazolin 1 g IV is ordered three times a day for a patient with pneumonia. It is supplied in 100 mL dextrose and water, to run over 20 minutes. How many milliliters per hour should you set the controller to deliver?
-
Solution
\(\frac{100\, mL}{20\, mins}\times \frac{1\, hr}{60\, mins}= 300\, mL/hour\)
A patient is receiving 250 mL normal saline IV over 4 hours, using tubing with a drip factor of 10 drops/mL. How many drops per minute should be delivered?
-
Solution
\(\frac{250\, mL}{4\, hrs}\times \frac{1\, hr}{60\, mins}\times \frac{10\, gtts}{mL}= 10\, gtts/min\)
Levothyroxine (Synthroid) 150 mcg PO per day is ordered for a patient with hypothyroidism. It is supplied as 0.075 mg tablets. How many tablets should the patient take daily? A safe dose of Synthroid is 1.5 mcg/kg/day. The patient weighs 196 pounds. Is the dose safe?
-
Solution
\(150\, mcg\times \frac{1\, mg}{1,000\, mcg}\times \frac{1\, tablet}{0.075\, mg}= 2\, tablets\)
\(\frac{150\, mcg}{196\, lbs}\times \frac{2.2\, lbs}{1\, kg}= the\, patient\, is\, receiving\, 1.7\, mcg/kg\)
*Not safe, the dose of 1.7 mg/kg is greater than 1.5 mg/kg, so the dose is too high
Each acetaminophen (Tylenol) #3 tablet has 325 mg of acetaminophen and 30 mg codeine. A patient is told to take 2 tablets PO every 4 hours for pain. The maximum safe dose of acetaminophen is 4 g/day. The safe dose of codeine varies with tolerance. Is the dose safe?
-
Solution
*Because the safe dose of codeine is variable and is determined by patient response, you only need to figure safe dose for the Tylenol for this problem.
\(\frac{325\, mg}{tablet}\times \frac{2\, tablets}{dose}\times \frac{6\, doses}{day}\times \frac{1\, gram}{1,000\, mg}= 3.9\, grams\, per\, day\)
*3.9 grams per day is less than the maximum safe dose of 4 grams, so it is safe.
Morphine sulfate 2 mg IV push is ordered to relieve shortness of breath in a patient with chronic lung disease. It is supplied as gr 1/6 /mL. How many milliliters should you administer?
-
Solution
\(2\, mg\times \frac{1\, gr}{60\, mg}\times \frac{1\, mL}{1/6\, gr}= 0.2\, mL\)
Atropine 0.6 mg IM is ordered preoperatively. It is supplied as 0.4 mg/mL. How many milliliters should you administer?
-
Solution
\(0.6\, mg\times \frac{1\, mL}{0.4\, mg}= 1.5\, mL\)
Diltiazem (Cardizem) 90 mg PO tid is ordered for a patient with hypertension. It is supplied in 60 mg scored tablets. How many tablets should you administer?
-
Solution
\(90\, mg\times \frac{1\, tablet}{60\, mg}= 1.5\, tablets\)
Heparin sodium, 1000 units/hour IV, is ordered for a patient with a blood clot in the leg. It is supplied as 50,000 units in 500 mL of dextrose and water. How many milliliters per hour should be set on the controller?
-
Solution
\(\frac{1,000\, units}{1\, hour}\times \frac{500\, mL}{50,000\, units}= 10\, mL/hour\)
Amoxil (amoxicillin) suspension 180 mg PO bid is ordered for a patient who cannot swallow pills. It is supplied as 125 mg/5 mL. How many milliliters should you administer?
-
Solution
\(180\, mg\times \frac{5\, mL}{125\, mg}= 7.2\, mL\)
You have on hand enoxaparin (Lovenox) 30 mg/0.3 mL. You need to administer 1 mg/kg SC. Your patient weighs 200 pounds. How much will you draw into a syringe?
-
Solution
\(\frac{1\, mg}{kg}\times \frac{0.3\, mL}{30\, mg}\times 200\, lbs\times \frac{1\, kg}{2.2\, lbs}= 0.9\, mL\)