Transcript Document 7596057

Special considerations for
age groups
Pediatrics
Elderly
Pregnancy
PEDIATRIC PT
Variations in Neonates: less than 1
month of age
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Smaller body mass
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Lower body fat content
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High body water volume
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Enhanced membrane permeability
Factors that influence drug absorption
immediately after birth:
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Lack of gastric acid
Absence of intestinal flora and
enzyme function
Decr gastrointestinal transit time
Immature liver
Incomplete development of renal
excretion system
Toxicity due to variable absorption.
Older infant and young child:
• differences produce less obvious
alterations in drug response.
• Better absorption, utilization and
excretion
Examples of drugs alterations:
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Penicillin antibiotics
Aminoglycosides
Digoxin
Adverse drug rxns in children
• Incr in very ill children and infants
• Infants exposed to drugs:
Transplacentally
Direct adminstration
Ingestion of breast milk
• Paradoxical reactions:
hyperactive with antihistamines/choral
hydrate
Sleepiness with stimulants like Ritalin
children are not just small
adults
• Children are not just small adults who
require a proportionally smaller dose
of medication.
• Respond differently to drugs, toxic
effects may develop more quickly and
stay around longer.
Preparation and administration
of medications to children
• Calculating
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the right amount
of the right medication
to the right child at the right time
in the right way
• Determining if a dosage is too high to be
be safe
• Determining if the dosage is too low to
have the desired therapeutic effect
Preparation and administration
of medications to children
• Calc by milligram/kilogram/hour or
day:
– mg/kg/d
– Amt of drug in relation to child’s wt in kg
for 24 hrs.
– Safe amt of drug always calculated in
mg/kg in references
– Normal amt of med given to children is
less than that given to adults
Preparation and administration
of medications to children
• Calculated amt to be given in 24 hrs
then divide by equal number of doses
• Number of doses determined by
recommended frequency of
administration
Preparation and administration
of medications to children
• Example:
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Amoxicillin 125 mg po
Child weighs 34.32 lb
You have amoxicillin suspension 125 mg/5ml
Usual dose is 20-50 mg/kg/day in divided doses
every 8 hours
Child’s wt is ________ kg
Safe recommended dosage of child is _______
Is the order safe?
How many ml will you administer?
.
Preparation and administration
of medications to children
• Step 1. Chg wt to kg: 2.2 lb in each kg
• Child weighs 34.32 lb
• Child’s wt is ________ kg
• Step 2. Determine safe recommended
dosage or range.
• You have amoxicillin suspension 125 mg/5ml
• Usual dose is 20-50 mg/kg/day in divided doses every
8 hours
Determine the total amt of medication ordered per 24
hrs_____
– Safe recommended dosage of child is _______
– Is the order safe?
Preparation and administration
of medications to children
• Step 3: calculate the actual dosage amt to
be given:
• amoxicillin suspension 125 mg/5ml
• in divided doses every 8 hours (tid)
Body Surface Area
• Determined by using a child’s ht and wt
along with the West nomogram
• See Edmund’s page # 91
Body Surface Area
• Child’s wt/ht
6 kg/110 cm
5 kg/19 in
25 kg/70 cm
30 lb/90 cm
160 lb/200 cm
• BSA
Body Surface Area
• Child’s wt/ht
6 kg/110 cm
5 kg/19 in
25 kg/70 cm
30 lb/90 cm
160 lb/200 cm
• BSA
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0.41 m2
0.81 m2
0.74 m2
0.58 m2
2.0 m2
Body Surface Area
• Calculate pediatric dosage using a formula:
• BSA in m2/1.7 X adult dose = child’s dose
Child wt: 24 lb
Adult dose is 100 mg
Body Surface Area
• Calculation of dosage based on BSA: means
of converting adult dose to a safe pediatric
dose.
• Three steps to calculation:
– Determine child’s wt in kg
– Calculate BSA in sq mtrs (m2)
– Calculate pediatric dosage using a formula:
• BSA in m2/1.7 X adult dose = child’s dose
Special considerations in
GERIATRIC PATIENT
Meds absorbed, metabolized, excreted more
slowly, less completely.
• Absorption: changes in GI tract with less
acid output, delayed motility in the bowel,
reduced blood flow slow down absorption.
• Distribution: decrease in total body water
and lean body mass thus less distribution in
some areas which can result in a greater
effect of the drug, or toxicity.
Distribution of drugs that are fatsoluble
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Digoxin
lithium
Gentamicin
meperidine
phenytoin
theophylline.
Lipid soluble drugs
• diazepam (Valium)
• some antidepressants
• antipsychotics.
Decrease in serum protein
(albumin)
• results in greater free concentration
of highly protein-bound drugs such
as:
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phenytoin,
warfarin,
naproxen,
Phenobarbital
some antidepressants.
decr in hepatic (liver) mass
and decr blood flow
• Affects drugs that have a high firstpass metabolism
• Includes drugs such as: diazepam,
barbiturates
Excretion:
o Great degree of variability in renal
function changes with ageing thus the
single most important physiologic factor
resulting in adverse drug reactions.
o Chronic diseases such as congestive heart
failure, liver disease and conditions leading
to dehydration affect renal function and
thus affect dosing.
Adverse Reactions
• Approx 90% of older people
experience adverse rxns to drugs/
20% of which require hospitalization.
• Approx 30,000 people may die/yr as
result of adverse drug rxns.
Drugs of concern
• Tranquilizers
• Sedatives
• Drugs that alter mind/change
perception
• Drugs which cause dizziness or
unbalanced.
• Diuretics, cardiac drugs.
Sxs of toxic rxns and adverse drug
effects to watch for in elderly:
• Diminished level of mental function,
incr fatigue, restlessness, irritability,
depression, weakness, dizziness,
headache, or disorientation.
• Problems which interfere with
appetite, balance, energy and lead to
dehydration, weight loss, falls and
immobility.
Noncompliance due to personal and
environmental factors:
• Cost of drug, difficulty in getting it from a
pharmacy
• poor memory and motivation to take drug,
• depression, feeling overwhelmed by
responsibility.
• Arthritis or disabling disease
• Poor eyesight…
• People diagnose each other’s ailments and
exchange medications.
Special considerations in
PREGNANT AND
BREASTFEEDING WOMEN
• chronic diseases, such as seizure
disorders, diabetes
• Impact on fetus -Avoid those drugs
with teratogenic potential
• Times of greatest risk:
• -first 2 wks after conception, fetal
period from 57 days until term i.e. all
of pregnancy.
Teratogenic drugs:
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antithyroid compounds
aminoglycoside antibiotics
Thalidomide
Coumadin (warfarin) and other
anticoagulants
• Lithium
• Anticonvulsants: phenytoin, valproic
acid carbamezepine
Top 10 drugs/ chemicals
pregnant women exposed to:
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analgesics
Antacids
Antibiotics
Antiemetics
Antihistamines
Diuretics
Alcohol
iron supplements
Sedatives
vitamins
Drugs contraindicated while
Breastfeeding
• cocaine, lithium, methotrexate,
amphentamines, nicotine, ergatomine,
and others
PRODUCTS/ MEDICATIONS
USED THROUGHOUT
LIFESPAN
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IMMUNIZATIONSANTIDIABETIC AGENTSANTIHYPERTENSIVE AGENTSCHOLESTEROL-LOWERING AGENTSOBESITY DRUGSANTIDEPRESSANT MEDICATIONSASPIRIN-
CULTURAL INFLUENCES
RELATED TO
MEDICATIONS
Effective nursing care is dependent
on an ability to assess the
differences in individuals related to
administration of medications based
on many factors including culture.
FACTORS RELATED TO
NONCOMPLIANCE WITH DRUGS
• Omission: not taken
• Commission: taking a medication not
prescribed
• Dosage error: not taking right dose
• Scheduling error: wrong schedule
Major risks of
noncompliance:
1. higher for preventative care medications
than ‘important’ meds such as cardiac or
anticonvulsant
2. increases w duration especially in chronic
disease such as hypertension, epilepsy,
depression, diabetes
3. highest for regimens that require
significant behavior changes such as wt
loss or smoking cessation
4. common cause of noncompliance is poor
understanding of instructions.
Noncompliance, cont:
5. increases when multiple drugs are
taken at same time or when frequent
intervals.
6. increases when unpleasant side
effects.