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Hesi rn dosage calculation
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Showing 10 questions, Sign in for moreHeparin 5,000 units IV is prescribed as a loading dose, to be administered over 5 minutes for a client with thrombophlebitis. The vial is labeled, "10,000 units/mL." How many ml. should the nurse administer? (Enter numeric value only. If rounding is required, round to the nearest tenth.)
Explanation
You can calculate the volume of heparin to administer using the following formula:
Volume (mL) = Dose (units) / Concentration (units/mL)
Here's what we know:
Dose: 5,000 units heparin (given)
Concentration: 10,000 units/mL (from the vial label)
Calculation:
Volume (mL) = 5,000 units / 10,000 units/mL
Volume (mL) = 0.5 mL
Therefore, the nurse should administer 0.5 mL of heparin.
The healthcare provider prescribes ampicillin 140 mg intravenously (IV) every 8 hours for a child with meningitis. The vial is labeled, "Ampicillin 250 mg for reconstitution with 8.3 ml, sterile normal saline for injection to yield a total solution concentration of 30 mg/mL." How many mL should the nurse administer? (Enter the numeric value only. If rounding is required, round to the nearest tenth.)
Explanation
We know:
Prescribed dose: 140 mg ampicillin (given)
Vial information:
Contains 250 mg ampicillin powder (given)
Reconstituted with 8.3 mL sterile normal saline (given)
Yields a final concentration of 30 mg/mL (given)
We don't consider the initial volume (8.3 mL) of sterile normal saline. The final concentration (30 mg/mL) refers to the concentration in the diluted solution after adding the saline
Calculation:
Volume to administer (mL) = Dose (mg) / Concentration (mg/mL)
Volume to administer (mL) = 140 mg / 30 mg/mL
Volume to administer (mL) = 4.67 mL (round to nearest tenth)
Therefore, the nurse should administer approximately 4.7 mL of the reconstituted ampicillin solution intravenously every 8 hours for the child.
The healthcare provider prescribes ganciclovir 375 mg intravenously (IV) every 12 hours to infuse over 90 minutes. The pharmacy delivers ganciclovir 375 mg in a 150 mL IV bag. How many mL/hour should the nurse program the infusion pump? (Enter a whole number only.)
Explanation
We can calculate the infusion rate for the nurse to administer ganciclovir considering accurate medication delivery and clinical practicality:
We know:
Dose per administration: 375 mg (given)
Infusion frequency: Every 12 hours (given)
Infusion duration: 90 minutes (given)
Total volume of ganciclovir solution: 150 mL (given)
Goal: Deliver the entire 375 mg dose of ganciclovir over the 90-minute infusion period.
Steps:
Calculate the volume to deliver per hour (considering the total volume needs to be infused):
Volume per hour (mL) = Total volume of bag (mL) / Infusion time (hours)
Volume per hour (mL) = 150 mL / (90 minutes / 60 minutes/hour) Convert minutes to hours
Volume per hour (mL) = 150 mL / 1.5 hours
Volume per hour (mL) = 100 mL/hour (round to nearest whole number)
2. Clinical considerations:
Ideally, the infusion rate should deliver the medication accurately within the timeframe.
Gravity infusion devices might have limitations in delivering very precise rates (e.g., fractions of mL/minute).
Some healthcare facilities might have specific rounding protocols.
Considering these factors:
100 mL/hour is the most appropriate rate in this case because it ensures the entire volume containing the medication is delivered within the prescribed infusion duration.
Therefore, the nurse should program the infusion pump to deliver 100 mL/hour.
The healthcare provider prescribes furosemide 120 mg intravenously (IV) for a client with fluid overload. Furosemide is available in a vial labeled 10 mg/mL, and the recommended rate for IV administration is 40 mg/minute. The nurse should administer the medication over what length of time in minutes? (Enter numeric value only.)
Explanation
Here's how to calculate the administration time for furosemide:
We know:
Total dose: 120 mg (given)
Concentration: 10 mg/mL (given)
Recommended rate: 40 mg/minute (given)
We need to find:
Administration time (minutes)
Since the recommended rate is the maximum safe rate, we will use it to determine the administration time.
Calculation:
We can directly set up a proportion to find the time based on dose, concentration, and desired rate:
Dose (mg) / Time (minutes) = Rate (mg/minute)
Plug in the known values and solve for time:
120 mg / Time (minutes) = 40 mg/minute
Time (minutes) = 120 mg / 40 mg/minute
Time (minutes) = 3 minutes
Therefore, the nurse should administer the furosemide over 3 minutes.
A client receives a prescription for a single dose of midazolam 2 mg IV to be administer before a scheduled procedure. The vial is label, "4 mg/2 mL." How many mL should the nurse administer? (Enter numerical value only.)
Explanation
Here's the answer and explanation again:
We know:
Prescribed dose: 2 mg midazolam (given)
Vial concentration: 4 mg/mL (label)
We need to find the volume (mL) in the vial that contains the prescribed dose (2 mg) considering the concentration (4 mg/mL).
Calculation:
Volume to administer (mL) = Dose (mg) / (Concentration (mg/mL) / 2)
We divide the concentration by 2 because we need the volume that delivers 2 mg (half the concentration).
Volume to administer (mL) = 2 mg / (4 mg/mL / 2)
Volume to administer (mL) = 2 mg / 2 mg/mL
Volume to administer (mL) = 1 mL
Therefore, the nurse should administer 1 mL of midazolam from the vial to deliver the prescribed dose of 2 mg.
The healthcare provider prescribes cefazolin 800 mg IM every 6 hours. The available vial is labeled, "Cefazolin 1 gram," and the instructions for reconstitution state, "For IM use, add 2.5 mL sterile water for injection to provide a total volume of 3.0 mL." How many mL should the nurse administer? (Enter numerical value only. If rounding is required, round to the nearest tenth.)
Explanation
Here's how to calculate the volume (mL) of the reconstituted cefazolin solution the nurse should administer for each dose:
1. We know the following:
Prescribed dose: 800 mg cefazolin (given)
Vial information:
Contains 1 gram cefazolin (given) = 1000 mg (since 1 gram = 1000 milligrams)
Reconstituted with 2.5 mL sterile water for injection (given)
Yields a total volume of 3.0 mL (given)
2. We need to find the concentration of cefazolin (mg/mL) in the reconstituted solution.
3. Then, we can find the volume (mL) to administer for the prescribed dose (800 mg) considering the concentration.
Steps:
a. Calculate the concentration after reconstitution:
Total volume after reconstitution = 3.0 mL (given)
Total amount of cefazolin after reconstitution = 1 gram (from the vial) = 1000 mg
Concentration (mg/mL) = Total amount of medication (mg) / Total volume after reconstitution (mL)
Concentration (mg/mL) = 1000 mg / 3.0 mL
Concentration (mg/mL) = 333.33 mg/mL (round to one decimal place)
b. Calculate the volume to administer:
Volume to administer (mL) = Dose (mg) / Concentration (mg/mL)
Volume to administer (mL) = 800 mg / 333.33 mg/mL
Volume to administer (mL) = 2.4 mL (round to nearest tenth)
Therefore, the nurse should administer approximately 2.4 mL of the reconstituted cefazolin solution intramuscularly every 6 hours.
The nurse is preparing a client's dose of an IM analgesic in a single syringe. The prescription is hydromorphone 4 mg and hydroxyzine 25 mg. The hydromorphone is available in a 10 mg/ml, ampule, and the hydroxyzine is available in a 50 mg/ml, vial. How many total mL should the nurse administer? (Enter the numeric value only. If rounding is required, round to the nearest tenth.)
Explanation
Here's how to calculate the total volume (mL) the nurse should administer for the combined medication dose
1. Calculate the volume for each medication:
Hydromorphone:
Dose: 4 mg (given)
Concentration: 10 mg/mL (given)
Volume (mL) = Dose (mg) / Concentration (mg/mL)
Volume (mL) = 4 mg / 10 mg/mL
Volume (mL) = 0.4 mL
Hydroxyzine:
Dose: 25 mg (given)
Concentration: 50 mg/mL (given)
Volume (mL) = Dose (mg) / Concentration (mg/mL)
Volume (mL) = 25 mg / 50 mg/mL
Volume (mL) = 0.5 mL
2. Add the volumes for each medication to find the total volume:
Total volume (mL) = Volume of hydromorphone (mL) + Volume of hydroxyzine (mL)
Total volume (mL) = 0.4 mL + 0.5 mL
Total volume (mL) = 0.9 mL (round to nearest tenth)
Therefore, the nurse should administer a total of 0.9 mL.
A client is receiving IV dextrose 5% in water (DSW) at 125 mL/hour and a secondary infusion of pantoprazole 40 mg IV daily. The pharmacy provides a 110 mL premixed solution of pantoprazole to be infused over 15 minutes. The nurse should program the secondary infusion to deliver how many mL/hour? (Enter numeric value only.)
Explanation
While the primary infusion rate (dextrose 5% in water) and the total volume of pantoprazole solution are provided, the pantoprazole infusion doesn't directly affect the rate of the primary DSW infusion.
Here's the breakdown:
Primary Infusion:
Dextrose 5% in water (DSW) at 125 mL/hour (given) - This rate remains constant throughout the secondary infusion.
Secondary Infusion:
Pantoprazole 40 mg total dose (given)
Premixed solution volume: 110 mL (given)
Infusion duration: 15 minutes (given) = 0.25 hours (convert minutes to hours)
The nurse programs the secondary infusion pump to deliver the 110 mL pantoprazole solution over 0.25 hours, independent of the primary DSW infusion.
Therefore, the nurse should program the secondary infusion pump to deliver a rate of:
Delivery rate (mL/hour) = Total volume (mL) / Infusion time (hours)
Delivery rate (mL/hour) = 110 mL / 0.25 hours
Delivery rate (mL/hour) = 440 mL/hour (This is the rate for the pantoprazole solution only)
In conclusion:
The primary DSW infusion rate remains at 125 mL/hour.
The secondary pantoprazole infusion rate is 440 mL/hour, but it delivers the total dose (110 mL) over the 15-minute timeframe.
The healthcare provider prescribes acyclovir 800 mg by mouth (PO) every 6 hours for an adolescent with chicken pox. The medication is available in 400 mg tablets PO. How many tablets should the nurse administer to the client every 24 hours? (Enter the numeric value only.)
Explanation
Here's how to calculate the number of acyclovir tablets the nurse should administer every 24 hours:
1. We know the following:
Prescribed dose per administration: 800 mg (given)
Frequency: Every 6 hours (given)
Tablet strength: 400 mg per tablet (given)
2. We need to find the total daily dose (mg) of acyclovir.
Calculation:
Total daily dose (mg) = Dose per administration (mg) x Frequency (number of administrations per day)
Total daily dose (mg) = 800 mg/dose x 4 doses/day (24 hours / 6 hours/dose)
Total daily dose (mg) = 3200 mg
3. Now, we can find the total number of tablets for the daily dose.
Number of tablets = Total daily dose (mg) / Dose per tablet (mg)
Number of tablets = 3200 mg / 400 mg/tablet
Number of tablets = 8 tablets
Therefore, the nurse should administer 8 tablets of acyclovir every 24 hours.
A 9-year-old child who weighs 66 lb is to receive gentamicin sulfate 2 mg/kg/dose every 8 hours for an Escherichia coli urinary tract infection. How many mg per dose should this child receive? (Enter numeric value only.)
Explanation
Here's how to calculate the gentamicin sulfate dosage for the child:
Convert weight from pounds to kilograms:
Weight (kg) = Weight (lb) / 2.2
Weight (kg) = 66 lb / 2.2
Weight (kg) = 30 kg (approximately)
Calculate the total gentamicin dose per dose:
Dose (mg/kg) x Weight (kg) = Total dose (mg)
2 mg/kg x 30 kg = 60 mg
Therefore, the child should receive 60 mg of gentamicin sulfate per dose.
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