© 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Math and Dosage Calculations for Health Care Third Edition Booth & Whaley Chapter

  • View
    219

  • Download
    3

Embed Size (px)

Text of © 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Math and Dosage Calculations...

  • Slide 1
  • Slide 2
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Math and Dosage Calculations for Health Care Third Edition Booth & Whaley Chapter 11: Calculations for Special Populations 11-1
  • Slide 3
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Learning Outcomes 11.1 Explain why dosages for special populations must be based on the individual patient. 11.2 Identify factors that affect the absorption, distribution, biotransformation, and elimination of drugs in special populations. 11-2
  • Slide 4
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill 11.3 Determine safe doses for special populations. 11.4 Calculate patient dosages based on body weight. 11.5 Find a patients body surface area (BSA). Learning Outcomes (cont.) 11-3
  • Slide 5
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill 11.6 Calculate patient dosages based on a patients BSA. 11.7 Describe volume and medication limitations for special populations. 11.8 Calculate infusion rates based upon body weight. Learning Outcomes (cont.) 11-4
  • Slide 6
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Introduction Two populations requiring extra consideration when calculating medication dosages Pediatric (less than 18 years old) Geriatric (over 65 years old) Risk of harm is far greater due to the way they break down and absorb medications. 11-5
  • Slide 7
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Introduction (cont.) Clarify all confusing drug orders Calculate with absolute accuracy Verify that dose is safe Seek assistance from your supervisor McGraw-Hill Do not take short cuts with medication calculations. 11-6
  • Slide 8
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Factors That Impact Dosing Standardized doses based on assumptions The patients body and age Body systems are fully developed and functioning Assumptions do not hold true for all populations or situations 11-7
  • Slide 9
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Factors That Impact Dosing PHARMACOKINETICS Study of how drugs are used by the body Absorption Distribution Biotransformation Elimination Understanding these processes allows for adjustments for special populations McGraw-Hill 11-8
  • Slide 10
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Factors That Impact Dosing PHARMACOKINETICS (cont.) Absorption Process that moves a drug from the site where it is given into the bloodstream IV medications bypass the absorption process Oral medications digestive system Topical through the skin McGraw-Hill 11-9
  • Slide 11
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Factors That Impact Dosing PHARMACOKINETICS (cont.) Distribution Process that moves the drug from the bloodstream to other body compartments Target site where the drug produces its desired effect McGraw-Hill 11-10
  • Slide 12
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Factors That Impact Dosing PHARMACOKINETICS (cont.) Biotransformation Process that chemically changes the drug in the body Occurs primarily in the liver Helps to protect the body from foreign chemicals including drugs McGraw-Hill 11-11
  • Slide 13
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Factors That Impact Dosing PHARMACOKINETICS (cont.) Elimination Process where the drug leaves the body Main route urine Other ways Air that we exhale Sweat Feces Breast milk Other body secretions McGraw-Hill 11-12
  • Slide 14
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Factors That Impact Dosing PHARMACOKINETICS (cont.) Adjust dose If one of the four processes are not functioning within certain limits Made according to nature and severity of patients condition May by higher or lower than standard doses McGraw-Hill 11-13
  • Slide 15
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Factors That Impact Dosing (cont.) Conditions that impact dosing Stomach or intestinal disorders Liver disorders Obesity Kidney disease Functions of body systems change over the life of a person. McGraw-Hill 11-14
  • Slide 16
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Factors That Impact Dosing (cont.) Newborns systems not fully developed pH of stomach is lower Thinner skin Liver still developing Less circulation to muscles Geriatrics systems deteriorate Skin and veins become fragile Decreased liver function Decreased kidney function Poor circulation McGraw-Hill 11-15
  • Slide 17
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Working with Special Populations Other Considerations Parent or caretaker may be administering or assisting with medications. Educate regarding medications Geriatric patients may have decreased awareness or understanding. McGraw-Hill 11-16
  • Slide 18
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Working with Special Populations GERIATRIC PATIENTS Show respect Listen to their concerns Encourage them to Use the same pharmacy to fill all prescriptions Have one primary care physician to monitor and approve all medications Keep a list of all medications McGraw-Hill 11-17
  • Slide 19
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Special Populations GERIATRIC PATIENTS (cont.) Decreased dexterity Injections Eye drops Open bottles Difficulty swallowing Drugs that cannot be crushed Foods that can be mixed with drugs McGraw-Hill 11-18
  • Slide 20
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Special Populations GERIATRIC PATIENTS (cont.) Hearing loss Do they understand instructions? Have them repeat information back to you Difficulty reading small print Labeling Tablet colors 11-19
  • Slide 21
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Special Populations GERIATRIC PATIENTS (cont.) Short-term memory loss Written instructions Medication calendars Pill dispensers Avoid OTC or herbal meds until discussing with physician. Do not take expired meds or borrowed meds. McGraw-Hill 11-20
  • Slide 22
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Teaching Patients About Medications 1.Name of the medication 2.Purpose 3.How to store it 4.How long to take the medication 5.How and when to take it 6.How to know if it is effective McGraw-Hill 11-21
  • Slide 23
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Teaching Patients About Medications (cont.) 7. Required follow-up tests, doctor appointments 8. Possible side effects and what to do 9. Interactions with other drugs and foods 10. Symptoms to report to the doctor 11. What to do if a dose is missed 12. Keeping a list of all medications McGraw-Hill 11-22
  • Slide 24
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Dosages Based on Body Weight Amount of medication per Weight of the patient per Unit of time 11-23
  • Slide 25
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Dosages Based on Body Weight Rule 11-1 Rule 11-1 Calculating dosage based on body weight: 1.Convert the patients weight to kilograms 2.Calculate the desired dose D by multiplying dose ordered by the weight in kilograms such as 11-24
  • Slide 26
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved McGraw-Hill Dosages Based on Body Weight (cont.) Rule 11-1 Rule 11-1 (cont.) 3.Confirm whether or not the desired dose is safe by checking the label, package insert, or product literature. 4.Calculate the amount to administer, using fraction proportion, ratio proportion, dimensional analysis, or the formula method. 11-25
  • Slide 27
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Dosages Based on Body Weight (cont.) Calculate the amount to administer to a 3-year-old weighing 34 lb. Ordered: hysocyamine sulfate 5 mcg/kg subq 1 h pre-anesthesia On hand: hysocyamine sulfate 0.5 mg/mL Convert 34 lb to kg = 15.5 kg McGraw-Hill Example 11-26
  • Slide 28
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Dosages Based on Body Weight (cont.) Find the desired dose: 77.5 mcg = D Find the amount to administer: 77.5 mcg = 0.0775 = 0.08 mg Amount to administer = 0.16 mL McGraw-Hill Example (cont.) 11-27
  • Slide 29
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Dosages Based on Body Weight (cont.) Pediatric injection volume Limited to size and age of the child Length and gauge of needle vary with age and size of the patient Geriatric injections Depth of injection may also vary due to reduce muscle size McGraw-Hill 11-28
  • Slide 30
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Pediatric Injections Stage of DevelopmentMaximum Volumes for IM Injections Infant0.5 1 mL Toddler, walking for at least 1 year 1 mL Preschooler/elementary school age 1 1.5 mL McGraw-Hill 11-29
  • Slide 31
  • 2010 The McGraw-Hill Companies, Inc. All rights reserved Ensuring Safe Dosages Drug orders written in several ways Check to see if dose ordered is a standard recommended dose Not les

Recommended

View more >