Chapter 4 additional info

1. DOSAGE CALCULATIONDOSAGE CALCULATION
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2. FUNDAMENTAL SKILLS:
Administration of Medication and Intravenous Solutions
I. Medication AdministrationI. Medication Administration
 Assess medication prescriptionAssess medication prescription
 Ask client about medication allergiesAsk client about medication allergies
 Assess client’s understanding of medications, intravenous (IV)Assess client’s understanding of medications, intravenous (IV)
solutions prescribedsolutions prescribed
 Assess client concerns about medicationsAssess client concerns about medications
 Assess six rights prior to and during administration processAssess six rights prior to and during administration process
 Assess vital signs prior to, during, and after administration,Assess vital signs prior to, during, and after administration,
depending on medicationdepending on medication
 Document administration of medication and client’s response toDocument administration of medication and client’s response to
medicationmedication
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3. II. Drug Measurement SystemsII. Drug Measurement Systems
 Metric systemMetric system
• Basic units are meter, liter, gramBasic units are meter, liter, gram
 Apothecary and household systemsApothecary and household systems
• Common apothecary units include grain, dram, ounceCommon apothecary units include grain, dram, ounce
• Common household units include tablespoon, teaspoon, minim,Common household units include tablespoon, teaspoon, minim,
dropdrop
 Additional common drug measuresAdditional common drug measures
• Milliequivalent (mEq) expresses the number of grams of aMilliequivalent (mEq) expresses the number of grams of a
medication contained in 1 milliliter (mL) of a normal solutionmedication contained in 1 milliliter (mL) of a normal solution
• Unit measures medication in terms of action, not physical stateUnit measures medication in terms of action, not physical state
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FUNDAMENTAL SKILLS:
Administration of Medication and Intravenous Solutions

4. III. ConversionsIII. Conversions
 Between metric unitsBetween metric units
• Convert larger to smaller, multiply by 1000, or move decimalConvert larger to smaller, multiply by 1000, or move decimal
point three places to rightpoint three places to right
• Convert smaller to larger, divide by 1000, or move decimalConvert smaller to larger, divide by 1000, or move decimal
point three places to leftpoint three places to left
 Between household and metric systemsBetween household and metric systems
• First step in calculation of dosages can use method of ratio andFirst step in calculation of dosages can use method of ratio and
proportionproportion
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FUNDAMENTAL SKILLS:
Administration of Medication and Intravenous Solutions

5. V. Medication LabelsV. Medication Labels
 Always check expiration datesAlways check expiration dates
 Contains generic and trade nameContains generic and trade name
 Check medication label against physician’s prescriptions,Check medication label against physician’s prescriptions,
medication administration recordmedication administration record
Slide 5Elsevier items and derived items © 2011, 2008, 2005, 2002 by Saunders, an imprint of Elsevier Inc.
FUNDAMENTAL SKILLS:
Administration of Medication and Intravenous Solutions

6. PYRAMID POINTSPYRAMID POINTS
IX. Injectable Medications in Powder FormIX. Injectable Medications in Powder Form
 Used if medication is unstable when stored in solution formUsed if medication is unstable when stored in solution form
 Powders must be dissolved with sterile diluent, usually sterile waterPowders must be dissolved with sterile diluent, usually sterile water
or normal saline; follow directions that accompany the vialor normal saline; follow directions that accompany the vial
Slide 6Elsevier items and derived items © 2011, 2008, 2005, 2002 by Saunders, an imprint of Elsevier Inc.
FUNDAMENTAL SKILLS:
Administration of Medication and Intravenous Solutions

7. Calculating MedicationsCalculating Medications
 Commonly used formulaCommonly used formula
• Desired/availableDesired/available ×× quantity = amount per dosequantity = amount per dose
Slide 7Elsevier items and derived items © 2011, 2008, 2005, 2002 by Saunders, an imprint of Elsevier Inc.
FUNDAMENTAL SKILLS:
Administration of Medication and Intravenous Solutions

8. Calculation of Infusions Ordered byCalculation of Infusions Ordered by
Unit DoseUnit Dose
 Most common medications measured by units are heparin sodiumMost common medications measured by units are heparin sodium
and regular insulinand regular insulin
 Calculate by determining amount of medication per 1 mL; thenCalculate by determining amount of medication per 1 mL; then
determine infusion rate (mL/hr)determine infusion rate (mL/hr)
Slide 8Elsevier items and derived items © 2011, 2008, 2005, 2002 by Saunders, an imprint of Elsevier Inc.
FUNDAMENTAL SKILLS:
Administration of Medication and Intravenous Solutions

9. Question 1Question 1
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The client is to receive 1000 mL of DThe client is to receive 1000 mL of D55W at a rateW at a rate
of 100 mL/hr. The drop factor is 10 drops/mL.of 100 mL/hr. The drop factor is 10 drops/mL.
The nurse adjusts the flow rate to deliver howThe nurse adjusts the flow rate to deliver how
many drops per minute?many drops per minute?
1.1. 10 drops10 drops
2.2. 13 drops13 drops
3.3. 17 drops17 drops
4.4. 20 drops20 drops
FUNDAMENTAL SKILLS:
Administration of Medication and Intravenous Solutions

10. ANSWERANSWER
 Answer:Answer: 33
 Rationale:Rationale: The first step is to determine how many hoursThe first step is to determine how many hours
the IV will last. This requires simple division of the totalthe IV will last. This requires simple division of the total
volume of mL to be infused (1000 mL) by the total mL pervolume of mL to be infused (1000 mL) by the total mL per
hour (100 mL), which is 10 hours. Then, convert hours tohour (100 mL), which is 10 hours. Then, convert hours to
minutes, which is 600 minutes. Next, use the formula tominutes, which is 600 minutes. Next, use the formula to
calculate the flow rate:calculate the flow rate:
 Total volume in mLTotal volume in mL ×× drop factordrop factor = flow rate in drops per= flow rate in drops per
minuteminute
 Time in minutesTime in minutes
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11. Question 2Question 2
The physician orders an IM dose of 250,000 units ofThe physician orders an IM dose of 250,000 units of
penicillin G benzathine (Bicillin). The label on the 10-penicillin G benzathine (Bicillin). The label on the 10-
mL ampule sent from the pharmacy reads penicillin GmL ampule sent from the pharmacy reads penicillin G
benzathine (Bicillin), 300,000 units/mL. How muchbenzathine (Bicillin), 300,000 units/mL. How much
medication will the nurse prepare in order tomedication will the nurse prepare in order to
administer the correct dose?administer the correct dose?
1.1. 0.25 mL0.25 mL
2.2. 0.8 mL0.8 mL
3.3. 1.5 mL1.5 mL
4.4. 8 mL8 mL
Slide 11Elsevier items and derived items © 2011, 2008, 2005, 2002 by Saunders, an imprint of Elsevier Inc.
FUNDAMENTAL SKILLS:
Administration of Medication and Intravenous Solutions

12. ANSWERANSWER
 Rationale:Rationale: Use the formula for calculating the appropriate medication dosage. In thisUse the formula for calculating the appropriate medication dosage. In this
question, performing a conversion is not necessary. The information needed to perform thisquestion, performing a conversion is not necessary. The information needed to perform this
calculation is the physician’s order (250,000 units of penicillin G benzathine [Bicillin]) andcalculation is the physician’s order (250,000 units of penicillin G benzathine [Bicillin]) and
the available amount of 300,000 units/mL. Next, use the formula to calculate the dosage:the available amount of 300,000 units/mL. Next, use the formula to calculate the dosage:
– DesiredDesired ×× mLmL = mL per dose= mL per dose
– AvailableAvailable
 __250,000 units____250,000 units__ = mL per dose= mL per dose
 300,000 units/mL300,000 units/mL
 250,000250,000 = 0.83 mL= 0.83 mL
 300,000300,000

 Test-Taking Strategy:Test-Taking Strategy: Follow the formula for the calculation of the correct dose. RecheckFollow the formula for the calculation of the correct dose. Recheck
your work with a calculator and make sure the answer makes sense. If you had difficultyyour work with a calculator and make sure the answer makes sense. If you had difficulty
with this question, review medication calculation problems.with this question, review medication calculation problems.
Slide 12Elsevier items and derived items © 2011, 2008, 2005, 2002 by Saunders, an imprint of Elsevier Inc.