Answer:
0.4 mL
Explanation:
In order to solve for the dose of antispasmodic and peptic ulcer disease medication glycopyrrolate (brand name Robinul) to be administered, the ordered dose of the medication must be multiplied by the dosage strength. The following formula show this equation:
ordered dose × dosage strength = administered dose
The ordered dose of the medication is the amount of medication written and prescribed by the provider. In this case, it is 150 micrograms (150 mcg).
The dosage strength of the medication is the available concentration usually provided by the stock from pharmacy, typically presented as a proportion. In this case, it is 0.4 milligrams per milliliter (0.4 mg / mL).
The first step in solving this equation is changing the micrograms in the ordered dose to milligrams so that it matches the dosage strength's units. To do so, this amount is multiplied by a conversion factor, a proportion of equivalency. 1 milligram is equivalent to 1000 micrograms, which can be written as 1 mg / 1000 mcg.
150 mcg × (1 mg / 1000 mcg)
mcg in both numerator and denominator cancel each other out, leaving mg as the remaining units of measurement.
150 × (1 mg / 1000)
= 150(1 mg) / 1000
= 150 mg / 1000
= 0.15 mg
This new ordered dose can now be used in the formula.
0.15 mg × (mL / 0.4 mg)
mg in both numerator and denominator cancel, leaving mL and the remaining unit.
0.15 × (1 mL / 0.4)
= 0.15 (1 mL) / 0.4
= 0.15 mL / 0.4
= 0.375
≈ 0.4 mL
If rounding to the nearest tenth, the nurse should 0.4 mL of glycopyrrolate IV.
For added information, in practice this medication order should be questioned and or held by nurse because it does not include the frequency at which the medication should be administered.
