Drug Dosage Calculation Exam 11

Text Mode – Text version of the exam

Questions

1. Nurse Jackie is in the neonatal intensive care unit, carefully monitoring a pre-eclampsia patient. The attending physician has instructed her to administer 4gm of Magnesium Sulfate intravenously over a span of 20 minutes. The available Magnesium Sulfate is in a concentration of 40gm per 1000mL IV bottle. As she prepares to set the IV pump, she calculates the appropriate rate in _____ mL/hour.

2. In the bustling emergency department, Nurse Sam is attending to a patient with a severe migraine. The doctor prescribes a 2gm/hour IV dose of Magnesium Sulfate. Sam recalls the available IV bottle contains Magnesium Sulfate at a concentration of 40gm/1000mL. He swiftly works out the correct pump rate in _____ mL/hour.

3. In the labor and delivery unit, Nurse Ava receives a prescription from the doctor for her patient in preterm labor. The order is for Ritodrine IV at a rate of 70 mcg/min. The pharmacy has sent over a premixed IV bag containing 150mg of Ritodrine in 500mL D5W. Ava needs to calculate the correct IV pump setting in _____ mL/hour.

4. Amidst a late-night shift, Nurse Oliver is attending a woman in preterm labor. The physician prescribes Ritodrine IV at a rate of 50 mcg/min. Upon receiving the medication, he observes that the pharmacy has prepared a premixed IV bag with 150mg of Ritodrine in 500mL D5W. As he gets ready to administer the medication, he wonders, “At what rate, in mL/hour, should I set the IV pump?”

5. In the busy labor ward, Nurse Emily is preparing to administer Pitocin to a laboring patient. The doctor’s order is for the Pitocin infusion to run at a rate of 6mu/min. Upon receiving the medication, she notes that the pharmacy has provided a solution of 10 units of Pitocin in 500mL of D5LR. Emily ponders, “What should be the correct IV pump setting in mL/hour to deliver this dosage?”

6. Nurse Alex is attending to a patient in labor who requires augmentation with Pitocin. The physician prescribes the Pitocin infusion to run at 16mu/min. As Alex retrieves the IV bag, he notes that the pharmacy has supplied a solution containing 10 units of Pitocin in 500mL of D5LR. Focused, Alex thinks, “To administer the required dose, at what rate in mL/hour should I set the IV pump?”

7. Nurse Ben is on the early morning shift, and he’s preparing the medications for his patient. Among the scheduled medications is Keflex, specifically 1.5 grams diluted in 50 mL of a 5% Dextrose solution. The pharmacy recommends this preparation be administered within a 30-minute timeframe. As Ben prepares to set the IV pump, he questions, “What should be the correct infusion rate in mL/hour for this particular medication?”

8. It’s a sunny morning, and Nurse Laura is adjusting the IV rate for one of her patients as per the physician’s instructions. The new order is to reduce the IV flow to 30ml/hour. Checking the IVAC, Laura notices that there are exactly 270 ml remaining in the current IV bag. Glancing at the clock, she notes that it’s precisely 10:30 am. Laura ponders, “At what time should I expect this IV infusion to be completed?”

9. Nurse Ethan is on a busy night shift in the ICU. The physician orders 1.5 liters of Lactated Ringers solution to be administered to his patient over a 12-hour period. He has IV tubing that delivers 20 gtt/mL at his disposal. As he prepares the IV, Ethan wonders, “What should be the rate of flow in gtt/min for this infusion?”

10. It’s a brisk Monday morning and Nurse Sarah is preparing the 10am medications for her patient. The schedule includes Keflex, 2.0 g diluted in 100 mL of a 5% Dextrose solution. As per the pharmacy’s instructions, this preparation should be infused over thirty minutes. As she adjusts the IV pump, Sarah thinks, “What would be the correct infusion rate in mL/hour for this medication?”

Answers & Rationales

1. Solution:

First, we need to determine how many mL of the solution contains the required 4gm of Magnesium Sulfate.

Given that the concentration of Magnesium Sulfate is 40gm per 1000mL, we can set up a proportion to find out how many mL contains 4gm of Magnesium Sulfate:

40gm is to 1000mL as 4gm is to X mL.

We can solve for X (the volume in mL that contains 4gm of Magnesium Sulfate) by cross-multiplying:

40gm * X mL = 4gm * 1000mL

Solving for X, we get:

X = (4gm * 1000mL) / 40gm
X = 100mL

So, 100mL of the solution contains 4gm of Magnesium Sulfate.

The physician has instructed Nurse Jackie to administer this over 20 minutes. However, the IV pump rate is typically set in mL/hour. Therefore, we need to convert the time from minutes to hours:

20 minutes = 20/60 hours = 1/3 hours

Now, we can calculate the rate in mL/hour:

Rate = Volume / Time
Rate = 100mL / (1/3) hours
Rate = 300 mL/hour

Therefore, Nurse Jackie should set the IV pump to administer the Magnesium Sulfate at a rate of 300 mL/hour.

2. Solution:

First, we need to determine how many mL of the solution contains the required 2gm of Magnesium Sulfate.

Given that the concentration of Magnesium Sulfate is 40gm per 1000mL, we can set up a proportion to find out how many mL contains 2gm of Magnesium Sulfate:

40gm is to 1000mL as 2gm is to X mL.

We can solve for X (the volume in mL that contains 2gm of Magnesium Sulfate) by cross-multiplying:

40gm * X mL = 2gm * 1000mL

Solving for X, we get:

X = (2gm * 1000mL) / 40gm
X = 50mL

So, 50mL of the solution contains 2gm of Magnesium Sulfate.

The physician has instructed Nurse Sam to administer this over 1 hour. Therefore, the rate in mL/hour is simply the volume of the solution:

Rate = Volume / Time
Rate = 50mL / 1 hour
Rate = 50 mL/hour

Therefore, Nurse Sam should set the IV pump to administer the Magnesium Sulfate at a rate of 50 mL/hour.

3. Solution:

First, we need to convert the dose from micrograms (mcg) to milligrams (mg) because the concentration of Ritodrine in the IV bag is given in mg.

1 mg = 1000 mcg

So, 70 mcg/min = 0.07 mg/min

The concentration of Ritodrine in the IV bag is 150mg in 500mL. We can set up a proportion to find out how many mL contains 0.07 mg of Ritodrine:

150mg is to 500mL as 0.07mg is to X mL.

We can solve for X (the volume in mL that contains 0.07mg of Ritodrine) by cross-multiplying:

150mg * X mL = 0.07mg * 500mL

Solving for X, we get:

X = (0.07mg * 500mL) / 150mg
X = 0.2333 mL

So, 0.2333 mL of the solution contains 0.07 mg of Ritodrine, which is the required dose per minute.

The physician has instructed Nurse Ava to administer this per minute. However, the IV pump rate is typically set in mL/hour. Therefore, we need to convert the time from minutes to hours:

1 hour = 60 minutes

Now, we can calculate the rate in mL/hour:

Rate = Volume / Time
Rate = 0.2333 mL/min * 60 min/hour
Rate = 14 mL/hour

Therefore, Nurse Ava should set the IV pump to administer the Ritodrine at a rate of approximately 14 mL/hour.

4. Solution:

First, we need to convert the dose from micrograms (mcg) to milligrams (mg) because the concentration of Ritodrine in the IV bag is given in mg.

1 mg = 1000 mcg

So, 50 mcg/min = 0.05 mg/min

The concentration of Ritodrine in the IV bag is 150mg in 500mL. We can set up a proportion to find out how many mL contains 0.05 mg of Ritodrine:

150mg is to 500mL as 0.05mg is to X mL.

We can solve for X (the volume in mL that contains 0.05mg of Ritodrine) by cross-multiplying:

150mg * X mL = 0.05mg * 500mL

Solving for X, we get:

X = (0.05mg * 500mL) / 150mg
X = 0.1667 mL

So, 0.1667 mL of the solution contains 0.05 mg of Ritodrine, which is the required dose per minute.

The physician has instructed Nurse Oliver to administer this per minute. However, the IV pump rate is typically set in mL/hour. Therefore, we need to convert the time from minutes to hours:

1 hour = 60 minutes

Now, we can calculate the rate in mL/hour:

Rate = Volume / Time
Rate = 0.1667 mL/min * 60 min/hour
Rate = 10 mL/hour

Therefore, Nurse Oliver should set the IV pump to administer the Ritodrine at a rate of approximately 10 mL/hour.

5. Solution:

First, we need to understand the concentration of Pitocin in the IV bag. The concentration is given as 10 units in 500mL.

The doctor’s order is for the Pitocin infusion to run at a rate of 6mu/min. Here, “mu” stands for “milliunits”, so we need to convert the dosage from milliunits to units because the concentration of Pitocin in the IV bag is given in units.

1 unit = 1000 milliunits

So, 6mu/min = 0.006 units/min

We can set up a proportion to find out how many mL contains 0.006 units of Pitocin:

10 units is to 500mL as 0.006 units is to X mL.

We can solve for X (the volume in mL that contains 0.006 units of Pitocin) by cross-multiplying:

10 units * X mL = 0.006 units * 500mL

Solving for X, we get:

X = (0.006 units * 500mL) / 10 units
X = 0.3 mL

So, 0.3 mL of the solution contains 0.006 units of Pitocin, which is the required dose per minute.

The physician has instructed Nurse Emily to administer this per minute. However, the IV pump rate is typically set in mL/hour. Therefore, we need to convert the time from minutes to hours:

1 hour = 60 minutes

Now, we can calculate the rate in mL/hour:

Rate = Volume / Time
Rate = 0.3 mL/min * 60 min/hour
Rate = 18 mL/hour

Therefore, Nurse Emily should set the IV pump to administer the Pitocin at a rate of 18 mL/hour.

6. Solution:

Nurse Alex needs to calculate the correct IV pump setting to deliver 16mu/min of Pitocin. The given concentration is 10 units of Pitocin in 500mL of D5LR.

First, we’ll convert the dosage from milliunits to units since the concentration of Pitocin in the IV bag is given in units.

1 unit = 1000 milliunits

So, 16mu/min = 0.016 units/min

Now, we can set up a proportion to find out how many mL contains 0.016 units of Pitocin:

10 units is to 500mL as 0.016 units is to X mL.

We can solve for X (the volume in mL that contains 0.016 units of Pitocin) by cross-multiplying:

10 units * X mL = 0.016 units * 500mL

Solving for X, we get:

X = (0.016 units * 500mL) / 10 units
X = 0.8 mL

So, 0.8 mL of the solution contains 0.016 units of Pitocin, which is the required dose per minute.

The physician has instructed Nurse Alex to administer this per minute. However, the IV pump rate is typically set in mL/hour. Therefore, we need to convert the time from minutes to hours:

1 hour = 60 minutes

Now, we can calculate the rate in mL/hour:

Rate = Volume / Time
Rate = 0.8 mL/min * 60 min/hour
Rate = 48 mL/hour

Therefore, Nurse Alex should set the IV pump to administer the Pitocin at a rate of 48 mL/hour.

7. Solution:

The volume of the Keflex solution that Nurse Ben has prepared is 50 mL, and the physician has instructed him to administer this over a 30-minute period.

However, the IV pump rate is typically set in mL/hour. Therefore, we need to convert the time from minutes to hours:

30 minutes = 30/60 hours = 0.5 hours

Now, we can calculate the rate in mL/hour:

Rate = Volume / Time
Rate = 50 mL / 0.5 hours
Rate = 100 mL/hour

Therefore, Nurse Ben should set the IV pump to administer the Keflex at a rate of 100 mL/hour.

8. Solution:

The rate of the IV flow is 30 mL/hour, and there are 270 mL remaining in the IV bag.

We can calculate the time it will take for the IV bag to be emptied by dividing the volume of the fluid by the rate of the IV flow:

Time = Volume / Rate
Time = 270 mL / 30 mL/hour
Time = 9 hours

So, it will take 9 hours for the IV bag to be emptied.

If it’s currently 10:30 am, we can calculate the time at which the IV bag will be emptied by adding the duration to the current time:

10:30 am + 9 hours = 7:30 pm

Therefore, Nurse Laura should expect the IV infusion to be completed at around 7:30 pm.

9. Solution:

First, we need to convert the volume of the Lactated Ringers solution from liters to milliliters, because the drip factor of the IV tubing is given in gtt/mL:

1.5 liters = 1500 mL

The physician has instructed Nurse Ethan to administer this over a 12-hour period. However, the drip rate is typically set in gtt/min. Therefore, we need to convert the time from hours to minutes:

12 hours = 720 minutes

Now, we can calculate the rate in gtt/min:

Rate = Volume / Time
Rate = 1500 mL / 720 min
Rate = 2.083 mL/min

The drip factor of the IV tubing is 20 gtt/mL, so we can calculate the drip rate by multiplying the rate in mL/min by the drip factor:

Drip rate = Rate * Drip factor
Drip rate = 2.083 mL/min * 20 gtt/mL
Drip rate = 41.67 gtt/min

Therefore, Nurse Ethan should set the IV to administer the Lactated Ringers solution at a rate of approximately 42 gtt/min (rounding to the nearest whole number).

10. Solution:

The volume of the Keflex solution that Nurse Sarah has prepared is 100 mL, and the pharmacy has instructed her to administer this over a 30-minute period.

However, the IV pump rate is typically set in mL/hour. Therefore, we need to convert the time from minutes to hours:

30 minutes = 30/60 hours = 0.5 hours

Now, we can calculate the rate in mL/hour:

Rate = Volume / Time
Rate = 100 mL / 0.5 hours
Rate = 200 mL/hour

Therefore, Nurse Sarah should set the IV pump to administer the Keflex at a rate of 200 mL/hour.