Deck 8: Dosage Calculations

Question 1

The nurse is preparing potassium bicarbonate (TriLyte) for a pediatric patient scheduled for a colonoscopy. The directions state to provide the preparation at an estimated rate of 25 mL/kg/hr. The child weighs 55 lbs. The nurse should encourage the child to drink how much of the solution each hour?

A) 1,375 mL
B) 480 mL
C) 625 mL
D) 3,025 mL

Answer 1

625 mL

Question 2

A patient admitted to the hospital with acute renal failure typically takes moexipril (Univasc) for hypertension. The patient's creatinine clearance is 32 mL/min, and the pharmacy recommends a 50% dose reduction for this medication. The patient's typical dose is 7.5 mg. The nurse would expect the physician to order which of the following doses?

A) 3.75 mg
B) 2.25 mg
C) 4.25 mg
D) 5.75 mg

Answer 2

3.75 mg

Question 3

While monitoring a patient receiving chemotherapy set to infuse over 3 hours, the nurse notes after the first hour that just over 160 mL of the original 500 mL has infused. Which action by the nurse is best?

A) Alter the pump setting to infuse at 150 mL/hr.
B) Alter the pump setting to infuse at 200 mL/hr to ensure the medication finishes on time.
C) Assure the patient the physician will be informed and new medication orders will be received.
D) Inform the patient the infusion rate is accurate.

Answer 3

Inform the patient the infusion rate is accurate.

Question 4

The nurse is preparing to provide finasteride (Proscar) 5 mg daily in combination with doxazosin (Cardura) 2 mg daily to a patient with benign prostatic hypertrophy. The pharmacy provides the finasteride in a 5-mg tablet and the doxazosin in a 1-mg tablet. How many tablets will the nurse provide?

Question 5

The nurse is passing morning medications for a patient with hypertension taking fosinopril (Monopril) 30 mg. The pharmacy supplies this medication as a 20-mg tablet. How many tablets will the nurse provide?

Question 6

While working in the pediatric clinic, the nurse examines the mouth of a 5-year-old patient being treated for leukemia and notes white patches and scattered ecchymosis. The nurse suspects the child has thrush and expects the physician to order fluconazole (Diflucan). This medication is typically dosed at 3 mg/kg. The child weighs 42 lbs. How many mg will be in each dose? (Round to the nearest tenths.)

Question 7

The nurse is caring for a 12-year-old patient who, after a kidney transplantation, is to receive sirolimus (Rapamune). The child weighs 38 kg and has a body surface area of 1.2 m². The medication has been ordered at a dose of 1 mg/m²/day and is provided by a pharmacy in a 60 mg/60 mL-solution mixed in glass bottle for oral provision. How many mL will the nurse provide each day?
1.2 m² x 1 mg = 1.2 mg/day; 1.2 mg/60 x 60 = 1.2 mL per day.

Question 8

The nurse provides a patient with 20 mL of megestrol acetate (Megace 40 mg/mL strength) and the patient reports, "I usually take one teaspoon of the long-acting formulation. Are you sure this is the right stuff?" The nurse checks with the pharmacy and learns 5 mL of megestrol extended release (Megace ES 125 mg/mL) is equivalent to 800 mg of Megace. Which response by the nurse is best?

A) "You are right. You should only take 5 mL of this medication."
B) "We don't carry the long-acting medication. This is the equivalent dose."
C) "You should be taking 20 mL of medication at home as well."
D) "We will hold the medication at this time and verify the order with the physician."

Question 9

A nurse working in the oncology clinic is providing doxorubicin (Adriamycin) 60 mg/m² to a patient whose body surface area is 1.6 m². What dose of doxorubicin (in mg) will be sent by the pharmacy?
1.6 m² x 60 = 96 mg

Question 10

The nurse is preparing to provide losartan (Cozaar) suspension (2.5 mg/mL) for a patient whose dose is 50 mg. How many mL will be provided?
50 mg divided by 2.5 multiplied by 1 = 20

Question 11

The student nurse is preparing to give a patient 20 mEq of potassium chloride (K-LOR). Directions state to mix the powdered medication with at least 4 oz of juice or water. The instructor would be satisfied with the student's preparation if the student had which of the following liquids?

A) 80 mL of apple juice
B) 120 mL of grape juice
C) 3 cups of water
D) 1 cup of fruit punch

Question 12

While providing care to a patient with advanced neuroblastoma, the nurse is preparing chemotherapy dosed at 75 mg/m². The patient's body surface area is 1.8 m². What dose (in mg) of chemotherapy will be provided?

Question 13

An antibiotic is reconstituted with 29 mL distilled water to create 50 mL of solution with a concentration of 100 mg/5 mL. How much medication, in mL, would the nurse obtain to provide a dose of 45 mg? (Round to the nearest hundredth.)

Question 14

The nurse receives orders to start metronidazole (Flagyl) 50 mg/kg/24 hours divided into three equal doses for a child who weighs 33 lb. The medication is provided in 250-mg tablets. How many tablets will the nurse provide with each dose?
Convert 33 lb to kg = 33/2.2 = 15 kg; 50 mg per kg = 50 x 15 = 750 mg given in 3 doses = 250 mg per dose. Tablets come in 250 mg so give 1 tablet.

Question 15

The nurse is caring for a patient starting diuretic therapy and is placed on strict intake and output measurements. In counseling this patient to maintain at least 1,500 mL intake per day, which beverages should the nurse instruct the patient to avoid?

A) Citrus juices and water
B) Coffee, beer, and most soda pop
C) Tomato juice, diet drinks, and lemonade
D) Electrolyte-based drinks, tea, and artificial sweeteners

Question 16

Trimethoprim and sulfamethoxazole (Septra) suspension contains 200 mg sulfamethaxazole in each 5 mL. The physician has ordered 10 mL every 12 hours. What is the total daily dose of sulfamethaxazole in mg?

Question 17

The nurse is preparing to provide evening medications. It is currently 8 p.m. At which scheduled military time will the nurse pass medications?

A) 16:00
B) 18:00
C) 20:00
D) 22:00

Question 18

Meloxicam (Mobic) is dispensed in solution with 7.5 mg/5 mL. The physician has ordered 0.125 mg/kg daily for a child with juvenile arthritis who weighs 68 lb. How many mL will the nurse provide? (Round to the nearest tenth.)
Convert 68 lb to kg = 68/2.2 = 30.9 kg; 0.125 mg per kg = 30.9 x 0.125 = 3.86 mg
3.86/7.5 x 5 = 2.57 mL = 2.6 mL

Question 19

A patient's physician orders read, "Cisplatin 20 mg/m²." The nurse has 100 mg/100 mL vial of cisplatin, and the patient's body surface area is 1.4 m². How much cisplatin in mL will the nurse draw up for infusion?

Question 20

The drug label of cefpodoxime (Vantin) indicates it should be suspended in 44 mL of distilled water to create 75 mL with a final concentration of 50 mg/5 mL. The patient's dose is 10 mg/kg/day divided into two equal doses. The patient weighs 88 lb. How many mL will the nurse provide with each dose? (Round to the nearest full mL.)

Question 21

The nurse is preparing to reconstitute amphotericin B powder to then instill the ordered dose into a 50-mL bag of IV for piggyback provision. Place the following steps in correct order.

Fifth

A)Instill sterile water into the vial with sterile powder.
B)Place a filtered needle on a sterile syringe.
C)Shake vigorously.
D)Calculate the patient dose to determine the amount of solution to withdraw from the vial.
E)Inject diluted medication into a 50-mL bag of D5W for infusion.
F)Withdraw desired dose of diluted medication.
G)Remove filter needle and replace with a new sterile needle on the syringe.

Question 22

The nurse is preparing to reconstitute amphotericin B powder to then instill the ordered dose into a 50-mL bag of IV for piggyback provision. Place the following steps in correct order.

Second

A)Instill sterile water into the vial with sterile powder.
B)Place a filtered needle on a sterile syringe.
C)Shake vigorously.
D)Calculate the patient dose to determine the amount of solution to withdraw from the vial.
E)Inject diluted medication into a 50-mL bag of D5W for infusion.
F)Withdraw desired dose of diluted medication.
G)Remove filter needle and replace with a new sterile needle on the syringe.

Question 23

The nurse is providing levofloxacin (Levaquin) 750 mg over 90 minutes. The antibiotic comes from pharmacy in a 150-mL solution bag. What rate (mL/hr) should be set on the IV pump to infuse the medication correctly?

Question 24

The nurse is preparing to reconstitute amphotericin B powder to then instill the ordered dose into a 50-mL bag of IV for piggyback provision. Place the following steps in correct order.

Seventh

A)Instill sterile water into the vial with sterile powder.
B)Place a filtered needle on a sterile syringe.
C)Shake vigorously.
D)Calculate the patient dose to determine the amount of solution to withdraw from the vial.
E)Inject diluted medication into a 50-mL bag of D5W for infusion.
F)Withdraw desired dose of diluted medication.
G)Remove filter needle and replace with a new sterile needle on the syringe.

Question 25

A patient has been given orders to receive IM ceftazidime (Ceptaz). The 1 gram vial is to be mixed with 3 mL sterile diluent to create a final solution concentration of 250 mg/mL. The patient's dose is 500 mg. How many mL will the nurse provide?

Question 26

The nurse is tallying intake for a patient receiving kidney dialysis who is on a 1,200-mL fluid restriction. The patient has had 2 cups of coffee, 1 cup of water, 4 oz gelatin, 1/3 of a 10 oz cup of soup, and half a carton (240 mL) of milk. How much additional fluid in mL can the patient consume for the remainder of the day?

Question 27

The nurse is preparing to reconstitute amphotericin B powder to then instill the ordered dose into a 50-mL bag of IV for piggyback provision. Place the following steps in correct order.

First

A)Instill sterile water into the vial with sterile powder.
B)Place a filtered needle on a sterile syringe.
C)Shake vigorously.
D)Calculate the patient dose to determine the amount of solution to withdraw from the vial.
E)Inject diluted medication into a 50-mL bag of D5W for infusion.
F)Withdraw desired dose of diluted medication.
G)Remove filter needle and replace with a new sterile needle on the syringe.

Question 28

The nurse is preparing to reconstitute amphotericin B powder to then instill the ordered dose into a 50-mL bag of IV for piggyback provision. Place the following steps in correct order.

Third

A)Instill sterile water into the vial with sterile powder.
B)Place a filtered needle on a sterile syringe.
C)Shake vigorously.
D)Calculate the patient dose to determine the amount of solution to withdraw from the vial.
E)Inject diluted medication into a 50-mL bag of D5W for infusion.
F)Withdraw desired dose of diluted medication.
G)Remove filter needle and replace with a new sterile needle on the syringe.

Question 29

The hospital has experienced a power outage and is on backup generator electrical support. The nursing staff is asked to convert all nonmedication IVs to gravity control. The nurse is caring for a patient whose IV fluids are infusing at "keep vein open," which is defined as 30 mL/hr per hospital policy. Using tubing with a drip factor of 15 gtt/mL, what rate (gtt/min) should the nurse use for the patient's IV fluids? (Round to the nearest full drop.)

Question 30

The charge nurse is doing patient rounds and notes a patient is receiving blood at a set rate of 100 mL/hr. The blood transfusion has finished and 500 mL of 0.9% NS is hanging as backup. To complete the transfusion, the nurse will flush the tubing by infusing 50 mL of the 0.9% NS over 10 minutes. What rate (mL/hr) should the pump be set to for the 0.9% NS infusion?

Question 31

The nurse is helping to support a medical station during a triathlon. A runner comes to the area with signs of heatstroke, and the nurse is instructed to initiate an infusion of 1 liter D5.45NS over 2 hours. Macrodrip tubing with a drip factor of 10 gtt/mL is available. What rate (gtt/min) will the nurse use to set the infusion? (Round to the nearest full drop.)

Question 32

The nurse is preparing to reconstitute amphotericin B powder to then instill the ordered dose into a 50-mL bag of IV for piggyback provision. Place the following steps in correct order.

Sixth

A)Instill sterile water into the vial with sterile powder.
B)Place a filtered needle on a sterile syringe.
C)Shake vigorously.
D)Calculate the patient dose to determine the amount of solution to withdraw from the vial.
E)Inject diluted medication into a 50-mL bag of D5W for infusion.
F)Withdraw desired dose of diluted medication.
G)Remove filter needle and replace with a new sterile needle on the syringe.

Question 33

The nurse is preparing to hang ciprofloxacin (Cipro) IVPB. The medication order is for 400 mg in 100 mL to infuse over 1 hour. What rate (mL/hr) should be set on the IV pump to ensure appropriate drug delivery?

Question 34

While training for a disaster drill, the nurse is told to infuse a 250-mL bag of IV fluids over 2 hours using a microdrip set up. What rate (gtt/min) will be used for this scenario?

Question 35

The ordered antibiotic is sent from a pharmacy in 50 mL of solution. The label says to infuse over 30 minutes. What rate (mL/hr) would be set on the IV pump?

Question 36

The nurse is preparing to reconstitute amphotericin B powder to then instill the ordered dose into a 50-mL bag of IV for piggyback provision. Place the following steps in correct order.

Fourth

A)Instill sterile water into the vial with sterile powder.
B)Place a filtered needle on a sterile syringe.
C)Shake vigorously.
D)Calculate the patient dose to determine the amount of solution to withdraw from the vial.
E)Inject diluted medication into a 50-mL bag of D5W for infusion.
F)Withdraw desired dose of diluted medication.
G)Remove filter needle and replace with a new sterile needle on the syringe.