7. Medication Administration and Safety for Infants and Children Flashcards
Pharmacokinetics in Children
> Difference between pharmacokinetics and pharmacodynamics
___ relates to what the medication does when traveling through the body over time
* What does the drug do to the body?
Pharmacodynamics
___ relates to how a medication travels through the body over time
* What does the body do to a drug?”
> ___
> ___
> ___
> ___
Pharmacokinetics
Absorption
Distribution
Metabolism
Excretion
Oral route
4 factors influence absorption along the gastrointestinal tract (GI)
> Gastric acidity
> Gastric emptying time
> GI motility or transit time through the GI tract
> Function of pancreatic enzymes
Gastric acidity
* Infants’ gastric secretions are less acidic (secretions slowly increase during the first two years of life)
> Eat more frequently so they have food and gastric enzymes in their stomach most of the time
> Formula or milk increases alkalinity of gastric enzymes thus decreasing absorption of medications that need an acidic environment; however, it increases absorption of medications that require a more alkaline environment - serum drug levels will be impacted by this
Gastric emptying time
> Intermittent and unpredictable in infants
> Slower than in older children which leads to a delay in time of medication reaching intestinal absorption site
GI motility or transit time through the GI tract
> Eating increases peristaltic activity
> Infants up to 8 months tend to have prolonged motility
> Diarrhea can also alter intestinal motility by increasing peristaltic movement
> The longer the transit time through the intestine, the more medication is absorbed; whereas shortened transit time decreases absorption
Function of pancreatic enzymes
> Pancreatic enzyme activity may be altered in infants for the first ___ months while GI system matures
> Medications that require certain pancreatic enzymes for dissolution and absorption may not be converted to a form that is appropriate for intestinal action
3
Other Routes
* Intravenous (IV)
> Immediately available for absorption in a child because peripheral circulation is less reliable and more responsive to changes in the environment; this may lead to vasoconstriction or vasodilation which affects absorption of parenteral medications
> Also cardiovascular system is less able to accomodate large or rapid changes in volume which can lead to fluid overload with poorly controlled IV infusions
> Immediate available for absorption
> Cardiovascular system is less able to accomodate large or rapid changes in volume intramuscular (IM)
> Children have less muscle - fewer injection sites
> Blood flow to muscle tissue can be unpredictable - can ↑ or ↓ absorption
Topical
> Infants and younger children have thinner outer skin layer and larger body surface area (BSA) to weight ratio
> Infants have more skin surface area relative to weight, absorption is greater
> Skin pH also varies with age which can affect absorption of topical medications
> Children are more prone to skin irritations - common skin irritations - contact dermatitis
Differences between baby and adult skin
Baby skin
> Faster rate of water loss
> Less NMFs (Natural Moisturizing Factor)
> Less melanin pigments
> Smaller corneocytes
> Thinner stratum corneum, epidermis
Differences between baby and adult skin
Adult skin
> Slower rate of water loss
> More NMFs (Natural Moisturizing Factor)
> More melanin pigments
> Larger corneocytes
> Thicker stratum corneum, epidermis
?
Refers to concentration of medication in body fluids and tissues
Distribution
Differences in Body fluids
* Body fluid in infants is about ___% of body weight; whereas in younger children it is about ___% of body weight
> Infants have greater fluid volume per weight - this may require a higher dose per kilo of water-soluble medication to achieve desirable effects
* Medication must be adjusted during illnesses to avoid overdosing or underdosing
> Most body fluid is in extracellular fluid compartment so with certain illness this fluid may be lost rapidly leading to fluid depletion
75%
60%
Differences in Fat percentages
> Percentage of body fat also varies with age… in infants is about 16% of body weight and slightly increases during the first year…then decreases again in a preschool child
> Percentage of body fat affects distribution of fat-soluble medications
Differences in proteins
> Medications bind to plasma proteins - mainly albumin for distribution
> Only free unbound medication is absorbed
> Preterm and newborn children have less levels of plasma protein - potentially increasing adverse drug effects
Blood-Brain Barrier
> Does not fully mature until about ___ years of age
> Barrier is LESS selective allowing distribution of medications into the central nervous system
→ May lead to encephalopathy with certain medication
> Immature CNS can lead to paradoxical effects of medications
→ e.g. meds that cause sedation in adults may cause hyperactivity in children
2
Metabolism
> Most medications are metabolized in the ___
> Preterm or newborn infants may have immature metabolic enzyme systems so may not metabolize all the medication given in one dose
> Toddlers and preschoolers may metabolize medication faster than adults so they may need higher doses or more frequent administration to achieve the desired therapeutic effect of a certain medication such as pain medication
liver
Excretion
* Most medications are excreted through the renal system (lower glomerular filtration rate and less efficient renal tubular function)
* Newborns renal system is immature
* Infants are also not able to concentrate urine
* Renal immaturity leads to inadequate amounts of medication being filtered out of the circulatory system and therefore being excreted
> This leads to medication circulating longer in the blood reaching toxic levels in the blood
* Fluid volume loss (dehydration) also decreases ability to excrete and can affect serum drug levels
Concentration
* Safe therapeutic levels maximize desired effect of medication and reduces risk of toxicity
* Peak and trough serum levels may be ordered to monitor medication concentrations
___ is the level at which serum concentration is the lowest…usually obtained just before the next scheduled dose
Trough
___ is the concentration of the medication after it has been distributed
Peak
Psychological and Developmental Factors affecting Medication Administration in Children
* ALWAYS APPROACH CHILD ACCORDING TO THEIR DEVELOPMENTAL LEVEL
* Always provide appropriate explanations
* Always give child choices
> Toddler holding med cup
* Restraints are NOT necessary
> Unless when injecting a medication - another staff member may hold child during administration to avoid injury
* Parents may help distract or comfort
* Honesty
> Nurses should be honest when explaining the administration process - unpleasant taste, painful or uncomfortable, approximately how long pain will last, what child can do to help (not move or hold cup)…pinching and stinging may be used for description
* Praising
> Helps gain trust and cooperation with future administration
* Rewarding
> Encourages and reinforces appropriate behavior - stickers
Infants
* Essential administration techniques to ___ ___ of liquid or oral medications or adverse effects from medications
* Ask for help from other staff members for squirmy infants
* Always inform parents of medication being administered - to prevent medication errors
* Cuddling and comforting before and after is important
prevent aspiration
Toddlers
* Ages __-__
* Magical thinking and may associate medication administration (mostly invasive) as for of punishment
* Age-appropriate explanations using play
* Allow older toddlers to examine equipment before procedure
* May sit on parents’ laps
* Praise, cuddling, rewards
2-3
Preschoolers
* Ages __-__
* Magical thinking may use therapeutic play and participation
* Offer as much control and choices as possible (juice or milk?)
* May need staff member to hold child still
* Adhesive bandages are important because they believe a Band-aid will “make it better”
3-5
School-age
> Fear loss of control, pain, and injury
> Understand more complex explanations as to “why” medication is needed
> Offer choices
> Often cooperate but may need distractors (squeezing hand, watching a video, listening to music)
> Praise and rewards still important in this age group
Adolescents
* Fear separation from peers and loss of control
* Understand adult explanations
* Praise cooperation
* Offer distractions
* Help find outlets for frustrations (draw, write)
Calculating Dosages
> National Patient Safety Goals
* Improving the safety of using medications in an effort to decrease medication errors
> Verify accuracy of dose ordered
> 1st recommended dose for medication is checked and a calculation is performed to ensure right dose has been ordered
mg/kg/day
> 2nd recommendation for number of divided doses is confirmed
Every four hours…three times a day…every 12 hours
> Last, ensure route of administration is correct
Medication Administration Procedures
* AVOID ERRORS
> “SIX RIGHTS” - right patient/child, right drug, right dose, right time, right route, and right documentation
> Check order…transcribed correctly…allergies noted?
> Always double check dosage calculation - make sure accurate child weight
> Ask another nurse to double check with certain medications
→ Insulin, oral hypoglycemic agents, dextrose hypertonic IV solution (20% or greater), narcotics/opioids, epidural/intrathecal administered medications, chemotherapeutic agents, digoxin or other inotropic medications, anticoagulants, anesthetic and moderate sedation drugs, potassium chloride, hypertonic sodium chloride, magnesium sulfate injection
Medication Reconciliation
* Upon admission a list of all medications, including over-the-counter and herbal, taken at home is obtained
* Nurse compares list to what was prescribed with hospital admission
* Nurse identifies and communicates discrepanices
“medication reconciliation”
* Assess parent’s knowledge of child’s medication
> Name, dose, number of times a day, knowledge of side effects, adverse reactions, last time taken
* Upon discharge reconciliation includes clear, detailed, written instructions of all medications to be given at home as well as communicating medication to next healthcare provider
* Increased use of computer systems (electronic medical records - EMR, computerized physician order entry - CPOE) reduces medication errors, improves communication and improves medication regimen - do not replace responsibility
Administration of Oral Medications
* Widely used
* Available in liquid (elixir or suspension), tablet or capsule, chewable tablet, and sprinkle (powder form)
* If child cannot swallow tablets or capsules…may have to give in liquid form or chewable tablet - if not available, then check if can be crushed or contents emptied
Not recommended to crush time-released medications
extended-release XR, controlled-release CR, sustained-release (SR), enteric-coated (EC)
* Assess gag reflex and ability to swallow prior to medication administration