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Rn Hesi Med Surg Dosage Calculations
Total Questions : 55
Showing 10 questions, Sign in for moreThe healthcare provider prescribes amoxicillin 500 mg every 8 hours for a child who weighs 88 pounds. The recommended maximum safe dose is 50 mg/kg/24 hour. The available suspension is labeled, Amoxicillin Suspension 250 mg/5 mL. Based on this child weight, how many mL should the nurse administer? (Enter numerical value only. (If rounding is required, round to the whole number.)
Explanation
To answer this question, we need to convert the child's weight from pounds to kilograms, and then calculate the safe dose range and the amount of suspension needed.
One pound is equal to 0.454 kg, so 88 pounds is equal to 0.454 x 88 = 39.952 kg. We can round this to 40 kg for simplicity.
The safe dose range is 50 mg/kg/24 hour, so for a 40 kg child, the safe dose range is 50 x 40 = 2000 mg/24 hour. This means that the child can receive up to 2000 mg of amoxicillin in a day.
The prescription is for 500 mg every 8 hours, which means that the child will receive three doses in a day, totaling 500 x 3 = 1500 mg. This is within the safe dose range.
The suspension is labeled, Amoxicillin Suspension 250 mg/5 mL, which means that every 5 mL of suspension contains 250 mg of amoxicillin. To find out how many mL of suspension are needed for one dose of 500 mg, we can use a proportion:
250 mg / 5 mL = 500 mg / x mL
Cross-multiplying and solving for x, we get:
x = (500 x 5) / 250
x = 10 mL
Therefore, the nurse should administer 10 mL of suspension for one dose of 500 mg
An adult client receives a prescription for diphenhydramine 15 mL by mouth every 12 hours PRN for pruritus. The bottle is labeled, diphenhydramine 12.5 mg/5 mL. What is the total daily dose in mg that the client receives? (Enter numerical value only.)
Explanation
To answer this question, we need to find out how many mg of diphenhydramine are in one dose of 15 mL, and then multiply by the number of doses in a day. The bottle is labeled, diphenhydramine 12.5 mg/5 mL, which means that every 5 mL of liquid contains 12.5 mg of diphenhydramine. To find out how many mg of diphenhydramine are in one dose of 15 mL, we can use a proportion:
12.5 mg / 5 mL = x mg / 15 mL
Cross-multiplying and solving for x, we get:
x = (12.5 x 15) / 5
x = 37.5
Therefore, one dose of 15 mL contains 37.5 mg of diphenhydramine.
The prescription is for every 12 hours PRN, which means that the client can take up to two doses in a day as needed. The total daily dose in mg that the client receives is therefore:
37.5 x 2 = 75 mg
A 4-year-old is admitted with croup and receives a prescription for a single dose of dexamethasone 0.6 mg/kg IM. The child weighs 35 pounds. How many mg should the nurse administer? (Enter numerical value only. If rounding is required, round to the nearest whole number.)
Explanation
To answer this question, we need to convert the child's weight from pounds to kilograms, and then multiply by the prescribed dose per kg.
One pound is equal to 0.454 kg, so 35 pounds is equal to 0.454 x 35 = 15.89 kg. We can round this to 16 kg for simplicity.
The prescribed dose is 0.6 mg/kg IM, which means that for every kg of body weight, the child should receive 0.6 mg of dexamethasone by intramuscular injection.
To find out how many mg of dexamethasone are needed for a single dose, we can multiply the child's weight by the prescribed dose:
16 x 0.6 =9.6
Therefore, the nurse should administer about 10 mg of dexamethasone for a single dose.
A client scheduled for coronary artery bypass surgery is to receive an intravenous infusion of 1 gram cefazolin in 50 mL 0.9% Sodium Chloride, USP over 30 minutes. The nurse should program the infusion pump to deliver how many mL/hour? (Enter numeric value only, as a whole number.)
Explanation
To answer this question, we need to calculate the infusion rate in mL/hour using the formula:
Infusion rate (mL/hour) = Volume (mL) / Time (hour)
We are given the volume of the infusion as 50 mL and the time as 30 minutes. We need to convert the time from minutes to hours by dividing by 60. Therefore, we get:
Infusion rate (mL/hour) = 50 mL / (30 / 60) hour
Infusion rate (mL/hour) = 50 mL / 0.5 hour
Infusion rate (mL/hour) = 100 mL/hour
The nurse should program the infusion pump to deliver 100 mL/hour. This is the numeric value and it is already a whole number, so no rounding is needed.
A client who weighs 91 kg receives a prescription for a continuous infusion of dopamine at 3 mcg/kg/min. The solution is labeled, "Dopamine 400 mg in 5% Dextrose Injection 250 mL." How many mL/hr should the nurse program the infusion pump to deliver? (Enter numeric value only. If rounding is required, round to the nearest tenth.)
Explanation
To answer this question, we need to calculate the infusion rate in mL/hr using the formula:
Infusion rate (mL/hr) = Dose (mcg/min) x Weight (kg) x 60 min / Concentration (mcg/mL)
We are given the dose of dopamine as 3 mcg/kg/min and the weight of the client as 91 kg. We need to find the concentration of dopamine in the solution by dividing the amount of dopamine by the volume of the solution. We are given that there are 400 mg of dopamine in 250 mL of solution. We need to convert mg to mcg by multiplying by 1000. Therefore, we get:
Concentration (mcg/mL) = (400 mg x 1000 mcg/mg) / 250 mL
Concentration (mcg/mL) = 400000 mcg / 250 mL
Concentration (mcg/mL) = 1600 mcg/mL
Now we can plug in the values into the formula and get:
Infusion rate (mL/hr) = 3 mcg/kg/min x 91 kg x 60 min / 1600 mcg/mL Infusion rate (mL/hr) = 16380 mcg/min / 1600 mcg/mL
Infusion rate (mL/hr) = 10.2375 mL/hr
The nurse should program the infusion pump to deliver 10.2 mL/hr. This is the numeric value and it is rounded to the nearest tenth, as instructed.
A client receives a prescription for 1 liter of lactated Ringer's intravenously (IV) to be infused over 12 hours. The IV administration set delivers 60 gtt/mL. How many gtt/min should the nurse regulate the infusion? (Enter numerical value only. If rounding is required, round to the nearest whole number.)
Explanation
To answer this question, we need to calculate the infusion rate in gtt/min using the formula:
Infusion rate (gtt/min) = Volume (mL) x Drop factor (gtt/mL) / Time (min)
We are given the volume of the infusion as 1 liter and the drop factor as 60 gtt/mL. We need to convert the volume from liters to milliliters by multiplying by 1000 and convert the time from hours to minutes by multiplying by 60. Therefore, we get:
Volume (mL) = 1 L x 1000 mL/L
Volume (mL) = 1000 mL
Time (min) = 12 hours x 60 min/hour
Time (min) = 720 min
Now we can plug in the values into the formula and get:
Infusion rate (gtt/min) = 1000 mL x 60 gtt/mL / 720 min
Infusion rate (gtt/min) = 60000 gtt / 720 min
Infusion rate (gtt/min) = 83.3333 gtt/min
The nurse should regulate the infusion at 83 gtt/min. This is the numerical value and it is rounded to the nearest whole number, as instructed.
The nurse plans to provide the next shift with the IV fluid balance for a client who had a 440 mL secondary infusion that was started 2 hours ago at a rate of 85 ml/hour via an infusion pump. What is the remaining volume to be infused? (Enter numeric value only.)
Explanation
To calculate the remaining volume to be infused, we need to subtract the amount of fluid that has been infused from the total volume of the secondary infusion. The amount of fluid that has been infused can be found by multiplying the infusion rate by the duration of the infusion. In this case, the infusion rate is 85 ml/hour and the duration of the infusion is 2 hours, so the amount of fluid that has been infused is 85 x 2 = 170 mL. Therefore, the remaining volume to be infused is 440 - 170 = 270 mL.
A client receives a prescription for oxytocin 2 milliunits/min intravenously (IV) for labor augmentation. The IV bag contains oxytocin 20 units in lactated Ringer's 1 liter. How many mL/hour should the nurse program the infusion pump to deliver? (Enter numerical value only.)
Explanation
1. Determine the concentration of oxytocin in the IV solution:
20 units of oxytocin in 1000 mL = 20,000 milliunits in 1000 mL.
Therefore, 1 mL contains 20 milliunits of oxytocin.
2. To find the mL/hour:
2 milliunits/min × 60 min/hour = 120 milliunits/hour.
3. Finally, calculate the mL/hour:
120 milliunits/hour ÷ 20 milliunits/mL = 6 mL/hour.
The nurse plans to administer a bolus dose of IV Heparin based on the client's weight. The prescribed bolus dose is 100 units/kg. The client weighs 198 pounds. How many units of Heparin should the nurse administer? (Enter numeric value only.)
Explanation
calculate the bolus dose of Heparin, we need to multiply the prescribed dose per kg by the client's weight in kg. To convert pounds to kg, we divide by 2.2. In this case, the client's weight in kg is 198 / 2.2 = 90 kg. Therefore, the bolus dose of Heparin is 100 x 90 = 9000 units.
During a home visit, the nurse learns that a client is taking calcium polycarbophil, an over the counter laxative. A single tablet contains 625 mg and the daily maximum dosage is 5 grams in divided doses. How many tablets could the client safely take in one day? (Enter the numeric value only. If rounding is required, round to the nearest whole number.)
Explanation
The client can safely take up to 8 tablets in one day. This is because 5 grams is equal to 5000 mg, and dividing that by 625 mg gives 8. The client should not exceed this amount to avoid adverse effects of the laxative.
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