Special Populations Flashcards
(45 cards)
1
Q
Dose based on
A
Weight that day
Pts age- gestational and chronological
Status of growth plates (Tanners stages)
Body surface area
2
Q
Tanners stages
A
Physical development stages for both males and females
Males- genital development
Females- breast
Both- pubic hair
Stages 1-5
Growth plates fuse 2 years after menses starts and growth spurt ends
3
Q
When is a child known to be an adult?
A
Age 12 only for psychiatric and asthma treatment
4
Q
Pediatric absorption skin
A
Skin: baby skin is more permeable than older children
- thin stratum corneum
- neonate ratio of surface area to weight much greater than in children
- skin rashes and breaks increase absorption
- occlusion (diapers) increase absorption
5
Q
Pediatric absorption blood flow
A
- blood flow to administration site may be erratic
- variability in muscle mass leads to erratic absorption of injected drugs
- variability in chemical characteristics may lead to erratic absorption of objected drugs
6
Q
Pediatric absorption GI
A
- decreased gastric acid secretion, reaches adult level by 1-3 years
- reduces bile salt for atom decreases bioavailability of lipophilic drugs
- slowed gastric emptying time- may have higher absorption as a result
- decreased or increased intestinal motility
- decreased microbial flora in the gut
7
Q
Pediatric distribution
A
- body composition: higher percentage of water, lower body fat- water decreases as age increases
- kids need more meds if water soluble
- infants need higher dosing of water soluble medications
- puberty makes dosing difficult- higher muscle mass and decreases fat
BBB and plasma
- decreased plasma proteins : reach adult by 12 months
- immaturity BBB- permeability to drugs and increased CNS effects until age 2
8
Q
Pediatric metabolism
A
- liver enzyme systems immature until age 2-4
- drugs metabolized in liver, kidneys, lungs, blood, GI tract and skin: dramatically increased in children can require more frequent or higher dosing
- most drugs metabolize slower in the neonate, some metabolize faster
- restricted plasma protein binding affects metabolism- higher levels of circulating bilirubin which will decrease
9
Q
Pediatric excretion
A
- primary through kidneys
- reduces renal blood flow
- decreased GFR
- decreased tubular function in kidneys
- ren not mature until 6-8 months
10
Q
Write peds Rx in …
A
Ml not cc
Include dose, concentration (250mg/ml) , frequency, and number of days
Calculate how many ml are needed
Round up unless toxic drug
Dose easily- 1-2 times per day
11
Q
Topical therapy
A
Always start with lowest concentration of medication and work way up
Not instant cure
12
Q
G6PD deficiency
A
- women are carriers
- hereditary x-linked enzyme deficiency
- Oxidizing medications or foods cause hemolysis and anemia
- stress or illness cause hemolysis and anemia
- most common culprits- aspirin, sulfa drugs, malaria drugs, high doses of vit C or vit K
13
Q
Gasping syndrome
A
Preterm neonates exposes to benzl alcohol preservation in IV solutions causing gasping, metabolic acidosis, renal failure etc
14
Q
Methemoglobinemia
A
- can occur at any age but most common before 4 months
- derivative of hemoglobin in which iron component has been oxidized from the Fe2+ state to Fe3+ state
- turns blood brown/black so it can’t carry oxygen
- can be heredity, more common acquired from medications
- symptoms cyanosis, hypoxemia, headache, dyspnea, lightheadedness, weakness, confusion, palpitations, chest discomfort, death
15
Q
Congenial long QT syndrome
A
- QTc> 0.44 seconds in absence of other in absence of underlying causes
- may be associated with bradycardia, second degree AV block, PVCs, v tach, abnormal t-waves
- family history of syncope, seizure, cardiac arrest
- untreated can cause torsades de pointed, syncope, sudden death
- BE WARY of macrolides, quinolones, antimalaria, amiodarone, antipsychotics
16
Q
Role of primary care provider in pregnancy
A
- recommend all women of childbearing age to take multivitamin with folate
- recommend prenatal vitamin to women actively trying to conceive
- confirm and date pregnancy by last menstruated period
- identify any teratogens have been encountered since conception
- counsel patients regarding over the counter medications
- stress safe meds and continue taking crucial meds
17
Q
Ovum
A
From fertilization to implantation (usually 10 days after ovulation )
Teratogens has all or none effect
18
Q
Embryo
A
From 2nd-8th week
Most crucial period of organogenesis
19
Q
Fetus
A
8th week to delivery
20
Q
Pharmacokinetics of pregnancy
A
- absorption: affected by n/v, delayed gastric emptying, decreased intestinal motility
- plasma volume: increases by 40-50%
- decreased serum albumin concentration, decreased binding
- higher volume of distribution - lower plasma concentration and lower steady state
- higher clearance rates, higher GFR
- decreased serum albumin concentration, decreased binding
21
Q
What crosses the placenta ?
A
- most drugs cross in unbound state
- high molecular weight, highly polar do not cross- only small amount may cross (ex: Insulin, glyburide, interferon, thyroid med)
- some drugs may decrease blood flow to placenta/fetus by vasoconstriction- resulting in smaller babies (ex nicotine)
- some drugs may trigger contractions of uterus potentially causing miscarriage or premature delivery ( ex prostaglandin)
22
Q
Common X drugs to avoid
A
Aspirin NSAIDS Statins Coumadin ACE inhibitors Angiotensin receptor blockers Oral contraceptives Sulfa drugs (3rd trimester) Flagyl (first trimester)
23
Q
Medications not to be used in lactation
A
Antineoplastic Bromocriptine Cyclophosphamide Cyclosporine Ergotamine Lithium Methotrexate Radiopharmaceuticals
24
Q
Best choices for lactation
A
Look everything up!
25
Choose a medication for lactation
```
Short half life
High protein bound affinity
Well studied in infants
Poor oral absorption
Lowest lipid solubility
```
26
Dosing medications
Administer single daily dose medications just before longest sleep interval for baby
Inform mother to breastfeed then dose
27
Prescribing: minimizing risk to nursing infants
```
Avoid drug therapy if possible
Use topicals
Safe for infants are safe for mothers
Safe for pregnancy are not necessarily safe for breastfeeding
Use reliable references
```
28
Transfer of medication to breast milk
Medications cross into breast milk by a concentration gradient (passive diffusion)
Only 1-2% reach Breast milk, nonionized, unbound past most easily
Drug concentration in breast milk is largely determined by maternal serum concentration. More lipid soluble will transfer more quickly
Ion trapping can occur in breast milk
29
Physiologic changes : mental
- changes in cerebral blood flow
- decreased brain mass
- decreased neurotransmitter concentrations
30
Physiologic changes :sensory
Sight: changes in visual acuity impair reading/taking medications
Hearing: difficult hearing instructions regarding medication with hearing loss
Smell/taste: decreased smell/taste- dry mouth= difficult swallowing pills
Peripheral sensation: increased peripheral neuropathy, peripheral circulation issues, decreased nerve function = increase fall risk
31
Physiologic changes: musculoskeletal
- decreased manual dexterity (trouble opening bottles)
- decreased mobility due to weakness and deformed joints
- gait disorders
- weight gain (fat): loss of protein muscle mass which affects protein binding drugs
- increased concentration of high liposoluble drugs in tissue (toxicity risk)
32
Pharmacodynamic changes
- altered receptor sensitivity: highest sensitivity to anticoagulants, cardiovascular and psychotropic drugs
- increases orthostatsis
- blunted reflex tachycardia: May be unaware of hypoglycemia
- more side affects from anticholinergic drugs
- increased porosity in BBB: increases effect of psychotropics
- higher risk of drug-drug interactions
- decreased elasticity of blood vessels
33
Pharmacokinetic changes in aging
- decrease cardiac output results in decreased blood flow to all organs, including brain
- medication and nutrient absorption can be affected by:
* bariatric, gastric and small bowel surgeries
* gastric atrophy
* number and type of medications taken
* PPIs
* interaction with adenosine triphosphate depended p-glycoproteins
* poor oral intake can result in hypoalbuminemia and affect meds that are highly protein bound
34
Phase 1 and phase 2 difference in aging
Phase 1- Foods/medications
| Phase 2- no changes
35
Common p450 inducers
```
Broccoli
Insulin
Omeprazole
Prednisone
St. John’s wort
```
Decrease free drug- doesn’t let drug stay in steady state long
36
Common p450 inhibitors
```
Grapefruit
Sulfa meds
sSRIs
Antifungals
Amiodarone
```
Increases and causes more free drug of the substrate
37
Renal function changes and aging
- decreased cardiac output (decreased blood flow) affects renal perfusion
- decreased GFR and tubular secretion
- diminished creatinine clearance
- renal changes may not cause symptoms, although symptoms may appear when GFR less than 35
- medication risks increase due to nephron loss as a result of aging
- *** drug half life and toxicity risks increase in its with renal dysfunction
38
Other aging changes
- diminished ability to adapt to physiologic changes
- increased likelihood of problems after hospitalization
- decreased mobility
- increased chance of bowel issues
- decreased strength
- diminished ability to regulate temperature
39
Polypharmacy
Use or misuse of drugs, Both prescription and non prescription and their interactions
*** watch out in elderly!!
40
Safety tips elderly
See pts regularly
Order labs to asses renal and liver function
Normal creatine doesn’t ensure normal kidney fnc
Beers list
ABCs for medication guidance
41
BEERs
List of potential harmful drugs in elderly
42
ABCs-A
Antis are medications that are almost always potentially problematic for use in older adults
“Anti”
43
ABCs -B
Barbiturates, Benzos, belladonna
Blockers- dehydration can lead to renal insufficjency , which is problematic for pts on beta blockers
B-lactams
44
ABCs-c
Other concerning
- aminoglycosides
- quinolones, sulfonylureas( hypoglycemia)
- cholinesterase inhibitors (interact with p450 inhibitors)
- inotropics (dig can cause dizziness and anorexia)
- Tylenol, nsaids (affect kidneys, can cause fluid retention, gi bleeds)
- opioids
- sedatives, hypnotics (increased half life)
45
Aspirin in elderly
- controversial
- can cause gastric ulceration and bleeding
- uncoated with food
