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NurseDive Free Nursing Practice Question
Which syringe would you select to administer Humulin R U-500 65 units?
This question is an excerpt from Nurse Dive's nursing test bank - Dosage calculation proctored exam (hellen fluid college). Take the full exam now
Full Explanation
Syringe 1: This U-100 insulin syringe with a 30-unit capacity is inappropriate for this task because the required dose of 65 units exceeds its maximum capacity. This syringe is calibrated for U-100 insulin, and using it for U-500 insulin would lead to a potentially fatal overdose.
Syringe 2: This is a U-100 insulin syringe with a 50-unit capacity. Its capacity is insufficient for the 65-unit dose. Critically, using a U-100 syringe for U-500 insulin would result in a significant medication error and a massive overdose.
Syringe 3: This is a U-100 insulin syringe with a 100-unit capacity. Although the 65-unit dose fits within its capacity, the unit markings are based on U-100 concentration, so drawing to the 65-unit line would actually administer 65 U-100 units, which is a severe overdose of U-500 insulin.
Syringe 4: This is a small-volume syringe calibrated in milliliters, not U-100 units. The proper dose of 65 units of U-500 insulin is calculated as 65 units / 500 units per mL = 0.13 mL. This syringe can accurately and safely measure this specific volume, making it the appropriate choice to prevent a dosing error.
Similar Questions
Calculate the amount to administer_________.
Ordered: Filgrastim 120 mcg subcut daily
See label for available medication
Full Explanation
Calculation:
Ordered dose: 120 mcg
- Identify the medication concentration:
The label states the concentration is 300 mcg/mL.
- Calculate the volume to administer.
Volume (mL) = Desired Dose / Available Concentration
= 120 mcg / 300 mcg/mL
= 0.4 mL
Ordered: Amoxicillin 250 mg tid for 7 days
On hand: See label
Note: Partial bottles are not dispensed.
How much amoxicillin should be dispensed?
Full Explanation
Rationale:
- Calculate the total milligrams of amoxicillin needed for the entire prescription.
Given:
Ordered dose is 250 mg.
Frequency is three times a day (tid).
Duration is 7 days.
Total milligrams needed = 250 mg/dose × 3 doses/day × 7 days
= 5250 mg.
- Determine the concentration of the medication from the label.
The label states the concentration is 250 mg per 5 mL.
Concentration = 250 mg / 5 mL
= 50 mg/mL.
- Calculate the total volume in milliliters (mL) required for the prescription.
Total volume needed = Total milligrams needed / Concentration
= 5250 mg / 50 mg/mL
= 105 mL.
- Determine the amount to dispense based on the bottle size and dispensing instructions.
The label indicates that each reconstituted bottle contains 100 mL.
The total volume needed is 105 mL, which is more than what one 100 mL bottle contains.
The note states, "Partial bottles are not dispensed." Therefore, two bottles must be dispensed to provide the client with a full course of medication.
Amount to dispense = 2 bottles × 100 mL/bottle
= 200 mL.
Ordered: Insulin lispro 24 units subcut 4 times daily, with meals and at bedtime, for 90 days.
On hand: 1,000 unit vials of insulin lispro
Note: Partial vials are not dispensed.
What is the amount to dispense?
A. 7 vials
B. 3 vials
C. 8 vials
D. 9 vials
Calculation: Calculate the total daily dose in units. Total daily dose = 24 units/dose × 4 doses/day = 96 units/day. Calculate the total units needed for the 90-day supply. Total units = 96 units/day × 90 days = 8640 units. Total units per vial = 1000 units. Calculate the number of vials needed. Vials needed = Total units / Units per vial = 8640 units / 1000 units/vial = 8.64 vials. Account for partial vials not being dispensed. Vials to dispense = 9 vials.
Full Explanation
Calculation:
- Calculate the total daily dose in units.
Total daily dose = 24 units/dose × 4 doses/day
= 96 units/day.
- Calculate the total units needed for the 90-day supply.
Total units = 96 units/day × 90 days
= 8640 units.
Total units per vial = 1000 units.
- Calculate the number of vials needed.
Vials needed = Total units / Units per vial
= 8640 units / 1000 units/vial
= 8.64 vials.
- Account for partial vials not being dispensed.
Vials to dispense = 9 vials.