drug therapy considerations across the lifespan

Drug Therapy Considerations

Across the Lifespan

Drug Therapy for Pediatric Clients

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Pediatric Drug Therapy• Approximately 75% of

all prescription drugs in the U.S. lack full approval by the FDA because most drugs are not studied on children.

• Studying the effects of drugs in children is a problem.

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Classification of Pediatric Clients

• < 1 month Neonate

• 1 month to < 2 years Infant

• 2 years to < 12 years Child

• 12 years to < 18 years Adolescent

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Absorption• Gastric acid (hydrochloric acid)

secretion in infants- less acidity • Decreased first pass effect• Increased topical drug

absorption• IM injection sites• Intravenous drug

administration - produce the least variable

response because the medication given completely bypass the absorption step

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Distribution• Dependent upon the

amount of water and/or fat present in the child, as well as plasma affinity of the drug and protein-binding activity• Water-soluble drugs more

effectively utilizedthan fat soluble-Protein binding capacity is

less (until age one year)

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Distribution

• Drugs that binds to CHON are generally bound to a lesser degree in pediatrics client than in adult…

due to: 1) low CHON concentration in

pediatric patient 2) decrease affinity of their

proteins for drug molecules

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Metabolism

• Difficult to predict • Immature liver

function

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Excretion• Depends on Glomerular

filtration, tubular secretion, tubular reabsorption

• Immature Kidney function• Glomerular filtration does not

reach adult levels until two years of age

• Excretion increases as the kidney matures• Drug toxicity decreases as the

kidney matures

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Pediatric Drug Sensitivity

• Central nervous system drugs- not fully mature until 8 months and blood-brain barrier more permeable during this time• Barbiturates and morphine

• Depressant effects are exaggerated

• Lowering body temperature• Acetaminophen

• Becomes toxic easily with large doses

• Salicylates • Do not give to children under the

age of 12.

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Pediatric Dosages

• Based on body weight• Body Surface Area• Determined by using a

nomogram• Nomograms are

generally accurate after the attainment of mature liver and kidney function.

• Pg 406 – Pickar Text

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West Nomogram

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Pediatric Dosage Calculation

• Clarks rule * Child Dose = [Wt of child (lbs) x

adult dose] ÷ Adult dose

• Young’s rule (1 yr to 12 yrs.) * Child Dose = [(Age in years) x (adult

dose)] ÷ (Age + 12)

• Fried’s Rule (up to 1-2 yrs.) * Child Dose = (Age in months x adult

dose) ÷ 150

Math exercise time 14

Accurate way to Determine BSA

•Metric BSA •m2 = ht (cm) X wt (kg)

divided by 3,600• Then take the square root

• Household BSA• m2 = ht (in) X wt (lb)• divided by 3,131• Then take square root

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Calculating Safe DosagesBased on Weight

• First step – convert pounds to kilograms

• Find recommended safe dose range – Drug Handbook Resource

• Calculate safe dose range mg/kg• Compare with ordered dose• Clarify with physician if dose is

below minimum or above maximum range

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Calculating Maintenance Fluids

• Formula:• 100 ml/kg/day for first 10

kg of body weight• 50 ml/kg/day for next 10 kg

of body weight• 20 ml/kg/day for each kg

above 20 kg of body weight

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Rights to Follow

• Allow adequate time for drug administration

• Gain the child’s trust• Never lie to the child

• Consider the child’s developmental level

• Prevent choking

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Administration Methods

• Liquid medications are administered using an infant dropper, syringe without a needle, or a small spoon

• Schedule medication when the infant is hungry

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Parenteral Medications• Explain the procedure to the

child and to the parents.• Use additional materials such

as:• Booklets• Coloring books• Puppets• Dolls• IV setup with colored water

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Painful Procedures• Allow the parents to stay.• Painful procedures should

be done in a separate room designated as the “owie” room.

• Use a firm positive manner.• Assemble equipment first.• Maintain the child’s safety.

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Intramuscular Injections

• Vastus lateralis is the preferred site for children under the age of 3.

• Ventrogluteal site is the preferred site for children over the age of 3.• The child should be walking.* Those who are receiving injections

in the dorsogluteal site must be instructed to lie on their stomach with the toes pointing inward to relax the buttocks muscle

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Anterior view of the location of the vastus lateralis muscle in a young child.

(continued)

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Considerations for IV administration

• Site selected must not limit child activities

• Gauge??• Methods for IV

administration - direct IV push (or 5

minutes or less) - soluset method - syringe pump

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Poisoning in Children

• Syrup of ipecac???• Vomiting must not be induced if

the child is comatose, poison is corrosive, or if it is a petroleum base

• Activated charcoal or magnesium sulfate given by health care professionals have proven to be safe and more effective in preventing gastric absorption of poison

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Final Step in Administering Drugs to Children

• Evaluate drug action• Remember • Children are vulnerable.• Be kind and patient.• Enjoy the children; you

will receive more than you give.

• Children generally have short attention span (1 to 5 minutes/ depends on year of development)

Drug Therapy for Geriatric Clients

Chapter 6

Drug Consumption

• Age ≥ 65 = increasing population growth• Elderly are estimated to consume

approximately 1/3 of all prescription drugs

• Estimate elderly use 3/4 of over-the-counter drugs

• Polypharmacy• Complicated by sensory impairment,

social isolation, inadequate nutrition, and poverty

Absorption

• Diminishes with increased age

• GI concerns• Reduced stomach acid (HCl)• GI absorptive surface area is

reduced • Prolonged gastric emptying rate• Use of laxatives and bran

reduce absorption• Blood flow to the intestines is

reduced• Reduced muscle tone in the

stomach and intestines

Distribution

• Water loss• Muscle loss• Fatty tissue increase• Protein binding:

decreased capacity

Metabolism

• General decline as age increases

• Causes are obscure; possibly due to:• Reduced blood flow to the

liver

Excretion

• Measure creatinine function • Blood flow to the kidneys

reduced• Renal function is reduced• Loss of intact nephrons

* The elderly are more likely to experience drug toxicity, because of accumulation of drugs

Drug Receptors

• Internal drug receptors may change• Results in diminished or

greater responses• Close monitoring is

required

Other Factors

• Memory loss• Sensory loss• Multiple health problems• Multiple medications at

multiple times• Use of multiple

pharmacies

Other Factors• Economic factors• Lack of education• Communication

problems• Cultural considerations• Diet therapy

Points to Remember

• Because of memory loss…the elderly may understand instructions given, but then forget the instructions shortly after unless ‘written down’

• Elderlies are prone to the risk of self-medication…due to sharing.

• Client response to therapy must be evaluated such as excessive sedation and orthostatic hypotension

Assessing the Elderly

• History of drug allergies• Current prescriptions• Current non-prescriptions• Herbal supplements• Home Environment• Social support• Financial concerns• Physical limitations

Implementation

• Oral medications• Position for administration:

high Fowler’s• Speak clearly and slowly.• Offer the most important

medication first.• Have plenty of liquid

available.• Do not rush the elderly client.

Intramuscular Medications

• Use ventrogluteal site.• Avoid deltoid muscle.• Avoid vastus lateralis

because of loss of muscle mass.

IV Medications

• Flow rate must be carefully monitored to prevent circulatory overload

• Signs/ symptoms of fluid overload

Storage

• Safe storage of medications• Keep out of the reach of

grandchildren and other young children.

Evaluation

• Evaluate• Communication: Does client

understand?• Can they understand regimen,

dosage, adverse effects, s/s to report, importance of compliance

• Can they demonstrate safe administration

• Do they experience any idiosyncratic responses

Teachings• Use visual aids• Avoid use of blue and

green, or yellow and white, as elderly often have difficulty distinguishing these colors

• Alcohol abuse is often left unrecognized

Promoting Health• Prevent infections.• Improve nutrition.• Encourage exercise and

activity.• Facilitate social

interaction.• Promote restful sleep.