Math for Medication Administration
17 Administering Medications IV Direct
Lesson
Learning Outcomes
By the end of this chapter, learners will be able to:
- identify factors which affect the rate of administration of IV direct medications,
- create a dose, volume, time table for use in administration of IV direct medications, and
- label a syringe to help keep track of medication delivery rate.
IV Direct Administration Rates
It is essential for medications administered directly into an IV line to be given at the correct rate to prevent complications. Information describing the appropriate rate will be available in the health agency’s drug reference manual. Ensure all factors about the patient’s context are considered when reviewing rate information in the reference manual. For instance, the rate may be different for a neonate versus an adult. In some cases, a variable rate is given and you will need to use critical thinking skills to determine the most appropriate rate, often in discussion with your nursing instructor or the most responsible nurse for the patient.
To determine how fast to administer an IV direct medication, you will need the following information:
- the medication order
- information about the patient’s context (eg. age, reason for medication order, hepatic function…)
- the administration information from the drug reference manual
- the total volume of medication to be administered
Once the rate of administration of the drug is determined, the actual administration of the drug must be timed to ensure it is given at the correct rate. In order to administer the drug evenly over a particular period of time, nurses often calculate a volume of medication to be given over specific time intervals (for example, every 15 seconds) during the administration period. The drug information in the text box below will be used to exemplify this process. It is important to note the information presented here should not be used for direct patient care, always review your agency’s drug reference manual for up to date information regarding the drug and the administration policy of your institution.
diazepam
Status Epilepticus: 5-10 mg IV/IM q5-10min; not to exceed 30 mg, OR 0.5 mg/kg PR (using parenteral solution), THEN 0.25 mg/kg in 10 minutes PRN
IV Direct: Administer undiluted over 3 min; no more than 5 mg/min
https://reference.medscape.com/drug/valium-diastat-diazepam-342902
1. Gather the information which will affect the rate of administration.
Supply: the concentration of diazepam in a vial is 5 mg : 1 mL
[latex]x\text{ mL}=\dfrac{\text{1 mL}}{\text{5 mg}}\times\text{10 mg}[/latex]
[latex]x\text{ mL}=\dfrac{\text{1 mL}}{5\cancel{\text{ mg}}}\times10\cancel{\text{ mg}}[/latex]
[latex]x\text{ mL}=\dfrac{1\text{ mL}\times{10}}{{5}}[/latex]
[latex]x\text{ mL}=2\text{ mL}[/latex]
2. Determine what volume of medication will be given in each time interval:
| Amount (mg) | Volume (mL) | Time Interval |
|---|---|---|
| 10 | 2 | 3 min (180 sec) |
| 5 | 1 |