8-practicetest Dosage Cal.docx

RED RIVER COLLEGE NURSING SKILLS LABORATORY

CALCULATIONS PRACTICE TEST

1.

Please read questions carefully.

2.

Show your work for each answer. Be sure to: • change all fractions to decimals • round off to 2 decimal points for mL, mg and kg (where appropriate) • for IV drip rates (gtt/ min) and flow rates (mL/ hr) round off to the nearest whole number when applicable • state the unit of measurement in each answer

3.

There are a total of 20 marks.

4.

The pass grade is 90% (18/20).

1.

GENTAMYCIN For I.V. use 40mg/mL Usual Dosage: Adults: 250mg in divided daily doses CAUTION: Federal law prohibits dispensing without prescription.

Each vial contains equivalent of 400mg Gentamycin. Dilution not required. Discard open solution after 24 hours at room temperature or 96 hours under refrigeration. See enclosure for prescribing information. EXPIRES 09/09/09

The physician’s order reads: Gentamycin 60 mg IV q8h How many mLs are required for one dose?

2.

PHENOBARBITOL For I.V. use only 1g/ 2mL Usual Dosage: Adults: 100 mg IV CAUTION: Federal law prohibits dispensing without prescription.

Vial contains Phenobarbitol equivalent to 5g. Keep from freezing. Protect from light. Discard open solution. Read accompanying circular. EXPIRES 09/09/09

The physician’s order reads: Phenobarbitol 100 mg IV daily X3 How many mLs are required for one dose?

3.

THIAMINE HYDROCHLORIDE For I.V. injection 100mg/mL Usual Dosage: Adults: 250 IV daily CAUTION: Federal law prohibits dispensing without prescription.

Vial contains equivalent of 1g Thiamine hydrochloride. Dilution not required. Discard open solution after 24 hours at room temperature or 96 hours under refrigeration. See enclosure for prescribing information. EXPIRES 09/09/09

The physician’s order reads: Thiamine hydrochloride 75mg IV tid for 2 weeks How many mLs are required for one dose?

4.

ADENOSINE For I.V. use only 3mg/2mL Usual Dosage: Adults: 6mg IV; may repeat for a maximum of 2 times CAUTION: Federal law prohibits dispensing without prescription.

Each vial contains 30mL. Keep from freezing. Discard open solution after 8 hours at room temperature or 72 hours under refrigeration. Read accompanying circular. EXPIRES 09/09/09

The physician’s order reads: Adenosine 6 mg IV stat How many mLs are required for one dose?

5.

TAZIDIME For I.V. use 500mg CAUTION: Federal law prohibits dispensing without prescription.

Add 5mL of sterile water for a final concentration of 500mg/5mL Stable for 24 hours at room temperature or 3 days in the refrigerator. Read accompanying circular. EXPIRES 09/09/09

The physician’s order reads: Tazidime 200 mg IV q6h a)

How many mLs are required for one dose?

b)

If there is medication left after you prepare your dose, how should you label the vial?

6.

TOBRAMYCIN For I.V. use only 300mg CAUTION: Federal law prohibits dispensing without prescription. EXPIRES 09/09/09

For a FINAL Concentration Add sterile NS: of: 10mg/ mL 30 mL 50mg/ mL

6 mL

100mg/ mL

3 mL

Stable for 48 hours at room temperature or 7 days in the refrigerator. Read accompanying circular.

The physician’s order reads: Tobramycin 75mg IV q8h

7.

8.

a)

Considering the information given above, how many mL of NS would you use to reconstitute the medication? (give only one answer)

b)

Based on how you answered 6a above, how many mLs are required for one dose?

The physician’s order reads: Oxacillin 300 mg IV q6h The patient weighs 43.5 kg. The nursing drug guide recommends a maximum of 5 – 7.5 mg/kg/dose. a)

What is the maximum safe dose for this patient?

b)

Is the ordered dose for your patient “safe”? (show your work to support how you arrived at your answer)

The physician’s order reads: Ticar 35 mg IV q4h The patient weighs 14 lb. The nursing drug guide recommends a maximum of 20 - 30 mg/kg/day. a)

What is the maximum safe individual dose for this patient?

b)

Is the ordered dose for your patient “safe”? (show your work to support how you arrived at your answer)

9.

10.

11.

The physician’s order reads: 2 L of D5NS to infuse over 14 hours a)

How many mL/ h will the IV need to run at in order to deliver the solution ordered?

b)

The drop factor of the IV tubing is 10 gtt/mL. What should you set the drip rate (gtt/min) at in order to deliver the solution as ordered?

as

The physician’s order reads: 100mL of NS to infuse over 30 min

a)

How many mL/ h will the IV need to run at in order to deliver the solution ordered?

b)

The drop factor of the IV tubing is 60 gtt/mL. What should you set the drip rate (gtt/min) at in order to deliver the solution as ordered?

as

The physician’s order reads: 1000mL of NS to infuse over 6 hours

a)

How many mL/ h will the IV need to run at in order to deliver the solution ordered?

b)

The drop factor of the IV tubing is 20 gtt/mL.

as

What should you set the drip rate (gtt/min) at in order to deliver the solution as ordered?

12.

13.

14.

1 L of D5W is to run over 10 hours. After 4 hours, there are 400 mL remaining in the bag. a)

Is the IV ahead or behind? (show your work to support how you arrived at your answer)

b)

Recalculate a new flow rate (mL/ h) in order to finish the IV on time.

c)

Does the new flow rate fit with acceptable practice? Explain your answer.

500 mL of NS is to run over 4 hours. After 2 hours, there are 350 mL remaining in the bag. a)

Is the IV ahead or behind? (show your work to support how you arrived at your answer)

b)

Recalculate a new flow rate (mL/ h) in order to finish the IV on time.

c)

Does the new flow rate fit with acceptable practice? Explain your answer.

PRONESTYL For I.V. use 1mg/mL Usual Dosage: Adults: 5mg per day for 10-14 days CAUTION: Federal law prohibits dispensing without prescription.

Contains the equivalent of 10mg Pronestyl. Dilution not required. Discard open solution immediately. See enclosure for prescribing information. EXPIRES 09/09/09

The physician’s order reads: Pronestyl 8 mg IV stat You decide to give this by the direct IV method. The drug monograph states that IV infusion is not to exceed 6 mg/ min.

15.

16.

a)

How many mLs are required for one dose?

b)

Over what period of time will you administer this dose? (if applicable, show your work to support that the time period you select is safe)

c)

Based on how you answered 14b above, how many mLs is that q15seconds?

The physician’s order reads: Aminophylline 80 mg/ h IV The drug is supplied in a bag containing 500 mg of Aminophylline in 50 mL of solution. a)

What is the concentration (mg/ per 1 mL) of Aminophylline in the bag?

b)

At what rate (mL/ h) would you deliver the medication?

The physician’s order reads: Regular Insulin 1 unit/ h IV The drug is supplied in a bag containing 10 units of Regular Insulin in 100 mL of solution. a)

What is the concentration (units/ per 1 mL) of Regular Insulin in the bag?

b)

At what rate (mL/ h) would you deliver the medication?

DOSAGE CALCULATIONS PRACTICE TEST ANSWER KEY

1.

60 mg 40 mg

X

2.

100 mg 1000 mg

3.

75 mg X 100 mg

4.

6 mg 3 mg

5a.

200 mg 500 mg

5b.

TAZIDIME

X

0.2 mL

2 mL =

1 mL = 0.75 mL

X

4 mL

2 mL =

X

05/05/05

1.5 mL

1 mL =

5 mL =

2 mL

500 mg/ 5mL 1400h

km

6a.

3 mL is the best choice because the final concentration matches the dose that you need to give. However, it would also be acceptable to use 6 mL or 30 mL. 6b.

If you picked 3 mL for previous answer then: 75 mg X 100 mg

1 mL =

0.75 mL

If you picked 6 mL for previous answer then: 75 mg 50 mg

X

1 mL =

1.5 mL

If you picked 30 mL for previous answer then: 75 mg 10 mg

X

1 mL =

7a.

7.5 mg

X

43.5 kg =

7b.

The maximum safe dose is 326.25 mg/ dose.

7.5 mL 326.25 mg/ dose YES the ordered dose is safe.

The patient is to receive 300 mg so →

8a.

14 lb = 6.36

kg 2.2

30 mg 8b.

X

6.36 kg =

190.8 mg/ day

The maximum safe dose is 189 mg/ day. The patient is to receive 35 mg X 6 doses = 210 mg/ day so →

9a.

2000 mL = 14 h

143 mL/ h

9b.

143 mL 60 min

10 gtt/mL =

X

10a. 100 mL = X__ 30 min 60 min 10b. 200 mL X 60 min

11b. 167 mL

X

24 gtt/ min

X = 200 mL/ h

60 gtt/mL =

11a. 1000 mL = X__ 6h 60 min

NO the ordered dose is not safe.

200 gtt/ min

X = 167 mL/ h

20 gtt/mL =

56 gtt/ min

60 min 12a. 1000 mL = X 10 h 1h 100 mL/ h

X = 100 mL/ h

X 4h = 400 mL should be infused

out of a 1000 mL bag so there should be 600 mL left is 400 mL left so →

IV is AHEAD in the bag. But there

(so IV needs to be slowed down)

12b. 400 mL = X X = 67 mL/ h 6h 1h 12c. It is usually acceptable practice to slow an YES, the new flow rate is acceptable. IV, even to TKO →

13a. 500 mL = X 4h 1h 125 mL/ h

X = 125 mL/ h

X 2h = 250 mL should be infused

out of a 500 mL bag so there should be 250 mL left in

IV is BEHIND

the bag. But there is 350 mL left so →

(so IV needs to be speeded up)

13b. 350 mL = X 2h 1h

X = 175 mL/ h

13c. Ordered rate is 125 mL/h.

New rate = 175 mL/ h which is more than the

NO, the new flow

25% of 125 mL is 31 mL. Therefore could safely ↑ flow rate by 31

acceptable 156 mL/h →

rate is not acceptable.

mL to 156 mL/h →

14a. 8 mg X 1 mL = 1 mg

8 mL

14b. Maximum rate is 6 mg/ min so

6 mg = 8 mg min X 14c. 2 min = 8 15 sec “blocks” so 8 mL = 8 “blocks” 15a. 500 mg = 10 mg/ mL

X = 1.33 min NOTE: Students are generally

50 mL 15b. 80 mg X 1 mL = 10 mg

8 mL/h

16a. 10 units = 100 mL

0.1 units/ mL

16b. 1 unit X 1 mL = 0.1 unit

10 mL/h required to give an IV medication over a minimum of 2 minutes so you should bump this answer up to

2 minutes. Because the drug monograph gives you only a minimum time for administering the med, it is acceptable for you to decide to do this.

1 mL/ 15 sec