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Chapter 5 Drug Therapy for Pediatric Clients. Classification of pediatric clients. < 37 weeks gestation: preterm < 1month: neonate/newborn 1 month-1 year: infant 1-3 years: toddler 3-6 years: preschooler 6-12: school-aged 12-20: adolescent. Pediatric Drug Therapy.
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Classification of pediatric clients • <37 weeks gestation: preterm • < 1month: neonate/newborn • 1 month-1 year: infant • 1-3 years: toddler • 3-6 years: preschooler • 6-12: school-aged • 12-20: adolescent
Pediatric Drug Therapy • Challenge to safety, effectiveness • Children change/grow • Physiological characteristics influence pharmacokinetics • Ethics: pediatric drug studies? • 75% of drugs not fully approved for pediatric use
Absorption • gastric pH, gastric emptying time, GI tract motility • At birth, gastric pH neutral or slightly acidic • Immaturity of hydrochloric acid-producing cells in the stomach • Diet high in alkaline foods (milk) • At 3 years, gastric pH is at adult level • Gastric emptying slower in premature infants
Absorption • IM injections dependent and muscle mass and blood flow to area • responses depend on development • Topical administration: similar • Infants: thinner epidermis= rapid drug absorption
Absorption • many factors influence drug absorption variability • IV drugs often cause the least variable response • bypasses absorption step in GI tract
Distribution • The passage of drug from absorption site to peripheral tissues • Dependent on amount of water and/or fat, affinity of drug for protein-binding sites in plasma and tissue • Age-related changes affect how fast drug acts and how much reaches receptor sites
Distribution • Water and fat content varies greatly in pediatric patients • Adult 55% water • Full-term infant 70-75% water • Premature infant 85% water
Distribution • Proteins like albumin, “bind” part of drug in an inactive state • unbound portion: active • “Bound” drug molecules may be released back into the system over time • Kids: drugs bind to protein to lesser extent • May produce a greater response - more active drug circulating • Blood-brain barrier not mature- more drugs enter central nervous system
Metabolism • Involve liver enzymes • Inactivates drugs and promotes elimination • Kids: variable d/t developmental and genetic differences in growth • Liver enzymes decreased (immaturity) • Maternal drug use: intrauterine exposure can alter neonate’s metabolizing enzymes and drugs transmitted through breast milk affect liver enzyme action • Children have higher metabolic rates
Elimination • Renal excretion primary pathway • Dependent on level of maturity of the kidneys • Immature kidneys also receive relatively low fraction of cardiac output • Medications circulate longer- more risk of toxicity • Drugs and dosages in neonates and infants must be assessed carefully
Drug Sensitivity • More sensitive (immaturity) • Drugs affecting CNS (morphine, barbiturates) have exaggerated effect • Central nervous system immature until ~8 months of age • Body temperature control more easily disrupted in pediatric patients: acetaminophen and salicylate overdose can raise temperature
Pediatric drug dosages • Usually calculated based on body weight- not very accurate but commonly used • May be determined by body surface area calculations and compared with charts called nomograms • Nomograms: use height and weight • Accurate only after liver and kidneys are mature
Pediatric calculations • Weight-based only: milligrams of drug per kilogram of child per day = mg/kg/day • Remember the daily dose probably is further divided into smaller doses to be given a number of hours apart • Body surface area: • Calculation review in Pickar • May be checked against a nomogram
Nursing considerations • child’s history and allergies • Establish trust • Understand developmental level of the child • Use kind, firm approach • Explain procedures clearly • When possible, give choices • Never deceive children • Do not mix medications with essential foods • Obtain parental assistance as appropriate • Use praise
Pediatrics: Drug administration • Otic meds: pull the pinna back and down for children < 3 years old • IV meds: gtt factor on Buretrol IV set is 60-100 gtts/mL • IV sites: secure in manner that doesn’t prevent child from playing or moving • IV/IM prep: use EMLA anesthetic cream 1-2 hours prior to injection
Poisoning • About half of calls to Poison Control Centers in 2010 were for children <6yrs • Preach prevention! • Do not recommend syrup of ipecac in home • Parents to call poison control before administering anything
Herbals • Use with caution with kids • More susceptible to adverse effects (immaturity) • Poison centers: herbal remedies and supplements • Not always safe • Need to educate that herbals are not FDA-regulated – consult herbal expert
Nursing Considerations • Need to know: let providers know about supplements • Parents: tell provider about all herbals, meds, supplements used by children
Teaching Children About Drug Therapy • Gear teaching to the child’s development • What does child know? • Correct misconceptions • Short attention span • role playing and visual aids • Praise, give rewards
Geriatric Drug Therapy • Elderly: ~ 13% of the population • Consume ~ 34% of prescription drugs • Polypharmacy: the practice of taking multiple medications • 2007: Up to 25% of hospitalizations of elders (>65yrs) are due to adverse drug rxns
Geriatric Drug Therapy • ‘red flag’ drugs: pp145-146 • Drug activity may differ • Research: legal, medical and ethical issues • Sensory impairment, social isolation, inadequate nutrition, poverty
Absorption • Reduced gastric acidity, emptying • Decreased muscle tone, motor activity • Reduction in blood flow to major organs • Thinner skin surface • IM absorption difficult to anticipate
Distribution • Body water content decreased • Body fat increased • Altered muscle tone • Decrease in protein-binding capability but may be absorbed into fatty tissue and released back into bloodstream over time -> cumulative effects
Metabolism • Enzyme levels are decreased • Reduced liver function, circulation • Decline in the body’s ability to transform active drugs into inactive metabolites • Drugs more likely to sedate and linger in the system
Elimination • Blood flow to kidney is reduced • GFR reduced by 40-50% • Tubular secretion and reabsorption decreased • Decreased number of intact nephrons • More likely to have drug toxicity • Creatinine clearance, BUN
Other Factors • Number and nature of drug receptors • May be a greater or diminished drug response: toxicity • Impaired homeostasis • Increased likelihood of adverse reactions • Communication problems
Other Factors • Sensory, memory losses • multiple pharmacies and providers • More drugs, more errors: polypharmacy • Interactions with nonprescription drug use, communication problems, sharing drugs, hoarding drugs, and dietary factors
Nursing Considerations • medication history • vital signs, height and weight • Assess sensory function, environment, support system, financial concerns, and physical or mental impairments • Ensure patient can access prescriptions
Drug administration • Try to use liquid PO drug forms, when possible, because absorption not much affected by gastric emptying rate • IM: use ventrogluteal site • Elders receiving IV infusions: fluid overload risk
Teaching the Geriatric Patient • hearing aids and glasses • Speak clearly and slowly • Keep sessions brief • visual aids; reading material (large print) • Help them figure out how to add new meds into their lives
Teaching the Geriatric Patient • Include family members • Caution: no more or less than prescribed, no outdated meds • diet, exercise (check with provider), adequate fluid intake • flu vaccine and pneumonia vaccines