Pharm E1- Peds

What is the gastric pH in full term infants (for the first 1-3 days)?

6-8 due to amniotic fluid

When does acid content for an infant reach the lower limit of adult values?

3 mos

Why is gastric absorption decreased in infants < 6 mos?

faster gastrointestinal emptying time (GIT)

Intramuscular absorption is ______ in neonates compared to adults.

decreased

Percutaneous absorption is _____ in neonates/infants due to thin skin that’s hydrates & inc perfusion.

increased

What term relates the amount of drug in the body to serum concentration?

volume of distribution (Vd)

A child in a critically ill state that is dehydrated would have ____ Vd

decreased

Why do newborns have increased Vd for hydrophilic medications?

greater extracellular water component → more distribution of drugs

Who has the “bigger bucket"“, requiring higher doses to reach the same blood levels?

neonates

What is the most important pathway in phase 1 metabolism reactions?

oxidation - CYP P450

How is CYP450 activity in full term infants?

half of that of adults (some enzymes dont activate until later)

How is GFR & SrCR in term infants for the 1st week of life?

increased

How is GFR in pre-term infants?

decreased

Tubular secretion & reabsorption are significantly ____ in the 1st year of life

decreased

What has a black box warning in children due to altered activity of CYP2D6 pathway (leading to exaggerated or diminished response)?

Codeine

What is a disadvantage of aged based dosing?

assumes maturation of ADME principles is equal in all patients (6 yr olds & 12 yr olds would respond the same to dose)

What is the MC dosing regimen in kids?

body weight (kids have increased med clearance based on wt)

What are disadvantages of bodyweight dosing?

potenital for overdosing or underdosing in overweight children

What are advantages to BSA dosing?

more precise for meds requiring calculations & limits potential for overdose based on weight

What are disadvantages to BSA dosing?

difficult to estimate & numerous calculations

An invasive bacterial infx occurring in the first 90 days of life, most commonly in LBW infants, is _____

neonatal sepsis

Neonatal sepsis- early onset or late onset?

• birth - day 6 of life

• group B strep, E coli, listeria

• manifestations: bacteremia

early onset

Neonatal sepsis- early onset or late onset?

• 7-89 days of age

• group B strep, e coli, staph, candida

• manifestations: bacteremia or focal infx

late onset

What is the treatment for early onset neonatal sepsis?

empiric tx: ampicillin + gentamicin x 10 days

What is the treatment for late onset neonatal sepsis?

ampicillin or vancomycin + gentamicin or cefotaxime

(bacteria x 10 days, meningitis x 14-21 days)

When should intrapartum abx (IA) be given for maternal prevention of GBS sepsis?

positive culture or risk factors (gestation < 37 wks, ROM ≥18 hrs, temp ≥100.4)

What is given for prevention of GBS sepsis?

PCN G q4 hours until delivery

alt: ampicillin

PCN allergy: cefazolin, clindamycin, vancomycin

When do you initiate GBS sepsis treatment in an infant?

ill appearing - start empiric tx

healthy appearing - look at chart

What are indications for tx of HSV in neonates?

first sign of disease or exposure to an active lesion

What is the treatment for neonatal HSV?

acyclovir (*monitor kidney function & BM suppression)

What is the disease of immature lungs caused by a deficiency of pulmonary surfactant?

RDS

When does surfactant production begin?

32 weeks GA (matures by 36 wks)

What factors increase surfactant?

antenatal steroids (betamethasone, dexamethasone), PROM, maternal HTN

What drugs are given for RDS?

Survanta (Beractant), Curosurf (Poractant Alfa), Infasurf (Calfactant), Surafaxin (Lucinactant)

How is RDS treatment administered?

via ET tube divided into 2-4 aliquots in different positions

** do not filter or shake (causes foaming → less effective)

What is the treatment for apnea of prematurity?

caffeine

What is the MC life shortening genetic dz in caucasians in the US that results in defective Cl- channels and abnormal epithelial electrolyte permeability?

cystic fibrosis (CF)

What accounts for 95% of morbidity & mortality in CF?

lung disease

After 6 mos of age, what becomes a repeated process for CF patients?

chronic & recurrent infectious bronchitis

What are the typical organisms associated with lung infections in CF patients?

staph, h. influenzae, pseudo

What organisms are late emerging in CF and indicate an advanced disease?

burkholderia cepacia, strenotrophomonas maltophilia, alcaligenes xylosoxidans, aspergillus

Which phenotype of pseudomonas is associated with a ccellerated decline of pulmonary function?

mucoid

Acute chest infx / “exacerbations” in CF patients are associated with/ high rate of morbidity & mortality and require what?

2-3 wks of intensive therapy

What do 90% of CF patients suffer from?

progressive pancreatic disease (can cause CF related diabetes)

Ketoacidosis is ____ in CF patients with hyperglycemia

rare

How would a CF patient with hypochloremic alkalosis present?

salt “frosting” & salty tasting skin

What is important for young CF patients during warm weather or acute gastroenteritis?

oral/IV hydration (excessive loss of salt in sweat → salt depletion episodes)

What treatment clears mucus from airways using percussion/vibrations and postural drainage?

chest physiotherapy (CPT)

What treatment approach for CF lung infections allows greater concentrations to reach the lungs and has less systemic SEs?

aerosolized abx

What drug?

• protein based drug - nebulized once every day

• reduces viscosity of CF sputum specimens

• shown to decrease number of exacerbations in mild-mod lung dz

Pulmozyme (Dornase Alfa)

What drug can treat pulmonary infx in CF patients, improving rheologic properties (flow), mucus transport, airway hydration, mucociliary clearance, and lung function?

Hypertonic Saline 7% INH

What should the sequence of treatment be for pulmonary exacerbations in CF?

mucolytics → CPT → abx

What IV abx should pseudo be treated in CF patients?

minimum 2 abx (aminoglycoside + B lactam)

What are the antipseudomonal beta lactams?

cefepime, ceftazidime, piperacillin//tazobactam, ticarcillin/clavulanate

What IV aminoglycosides cover pseudo?

tobramycin, gentamicin, amikacin

What oral abx can be used to tx staph pulmonary infx in CF pts?

dicloxacillin, cephalexin, clindamycin, augmentin, macrolide

What oral abx can be used to tx h. influenzae pulmonary infx in CF pts?

amoxicillin, augmentin, 2nd or 3rd gen ceph

What oral abx can be used in young CF pts to prevent admission?

cipro; tobramycin or colistin via inhalation

Antibiotic doses are usually ______ in CF treatment.

higher

What anti-inflammatory agents can be used to treat pulmonary infx in CF patients?

corticosteroids, ibuprofen, macrolides (azithromycin on MWF)

What diet is recommended for CF pediatric patients?

high protein, high calorie, normal amounts of fat

What do pancreatic enzyme replacement therapies for CF patients contain?

lipase, protease, amylase

What are common pancrelipase products used in CF patients?

Pancrease, Creon, Zenpep, Ultrase

What should be added to pancreatic enzyme supplement tx if dosing reaches > 3000 units lipase/kg/meal?

PPI or H2RA to increase fat absorption

What can a high dose of pancreatic enzyme supplements (>20,000 units lipase/kg/day) cause?

fibrosing colonopathy and colonic strictures

What vitamins should be included in GI tx of CF patients?

fat soluble vitamins (aquADEK, source CF, vitamin, ABDEK)

What drug?

• tx biliary cirrhosis in CF patients

• derived from bear bile

• dec cholesterol content of bile by reducing cholesterol secretion form liver

ursodeoxycholic acid (ursodiol - aczigall)

What is contraindicated in the treatment of GERD in CF patients?

cholinergic agonists (increases mucus secretion)

What can be used to treat GERD in CF patients?

PPIs

what drugs?

• newer agents for CF - homozygous F508del

• take w/ fatty foods

• improves CFTR channel

• SE: fatigue, rash, mentraul irregularities if on OCP, diarrhea/flatulence, dyspnea, chest discomfort, hepatotoxicity rare (usually well tolerated)

Lumacaftor and Ivacaftor (Orkambi)

What lifestyle modifications can be made for children with GERD?

infants: thicken formula (rice cereal) & hypoallergenic formula

children/adolescents: avoid caffeine, chocolate, & spicy foods

What drug?

• neutralizes gastric acid

• requires frequent administration

• episodic tx for GERD; long term regular use NOT recommended

antacids (calcium carbonate & magnesium/aluminum hydroxide)

What mucosal protectants can be used to treat FERD in pediatric patients?

Sodium alginate (Gaviscon) & Sucralfate (Carafate)

what drug?

• prokinetic - DA receptor antagonist

• enhance motility of esophageal smooth muscle, accelerate gastric emptying, and inc antral contractions

• give 30 mins before meals & at bedtime

Metoclopramide (Reglan)

What drug?

• prokinetic - macrolide abx

• motion receptor agonist

• many drug interactions - CYP3A4 & 1A2 inhibitor

Erythromycin (E.E.S.)

What drugs competitively inhibit interaction of histamine with H2 receptors on the gastric parietal cell resulting in decreased acid secretion?

H2RAs (Nizatidine, Famotidine, etc)

What H2RA should not be used because it is a strong CYP3A4 inhibitor?

cimetidine (Tagamet)

What drugs irreversibly bind and deactivate the H+K+ATPase pump and should NOT be crushed or chewed?

PPIs

which type of constipation is MC in children?

functional

What is the treatment for constipation in breast fed infants?

usually only reassurance and close follow up (common occurrence)

What oral medications can be used to treat constipation in children?

mineral oil, polyethylene glycol electrolyte solutions, mag hydroxide/citrate, lactulose, sorbitol, Senna, bisacodyl

What rectal medications can be given to tx constipation in children?

phosphate soda enemas (avoiding < 6 mos), saline enemas, mineral oil enemas followed by phosphate, glycerin suppository, biscodyl suppository

What enemas are not recommended in children due to electrolyte disturbance?

soapsuds, tap water, magnesium

What should be avoided in very young children (< 6 mos) due to risk of fatal hyperphosphatemia?

phosphate soda enemas

What carbohydrates can be used to treat constipation in children?

prunes, pears, apple juice

What laxatives are not recommended in infants?

stimulant laxatives

What tx is usually given first for infants with constipation?

glycerin suppository