BCPPS key terms

The time required for the plasma concentration of a drug to fall by half. In children it changes with age because hepatic metabolism and renal clearance mature at different rates.

A method of converting drug doses between body sizes using metabolic weight, typically weight raised to the 0.75 power, rather than simple linear weight, because clearance does not scale proportionally with size.

Calculating a dose from the patient's surface area in square meters, usually with a nomogram; preferred for drugs with narrow therapeutic indices such as chemotherapy and for children above roughly 10 kg.

Measuring serum drug concentrations to individualize dosing for agents with narrow therapeutic ranges, such as aminoglycosides, vancomycin, phenytoin, and immunosuppressants; interpretation depends on when the sample is drawn relative to the dose.

Gestational age at birth plus chronological age in weeks. It is used to classify prematurity, adjust drug dosing, and judge organ maturity when selecting medications for newborns.

Chronological age minus the number of weeks the infant was born before 40 weeks' gestation. It is used to interpret growth and development and to guide dosing in infants up to about two years.

The share of body weight that is water, highest in premature neonates (roughly 80 to 85 percent) and falling with age. It enlarges the volume of distribution for water-soluble drugs and predisposes infants to dehydration.

A pause in breathing lasting 20 seconds or longer, or shorter if accompanied by bradycardia or desaturation, occurring in infants born before 37 weeks because respiratory control is immature.

A methylxanthine used to prevent and treat apnea of prematurity. A loading dose is followed by once-daily maintenance, with serum concentrations checked only when toxicity or poor response is suspected.

The fetal vessel joining the pulmonary artery and aorta that normally closes after birth. In preterm infants it may stay open, causing pulmonary overcirculation and requiring cyclooxygenase inhibitors, acetaminophen, or surgical closure.

A continuous infusion that keeps the ductus arteriosus open in ductal-dependent congenital heart lesions. Apnea is a common adverse effect, so airway equipment and personnel should be immediately available.

The lowest antimicrobial concentration that prevents visible growth of a bacterial isolate in vitro. It is combined with pharmacokinetic indices to judge whether a given dose will be effective.

The exposure measure that best predicts antimicrobial killing for a drug class, such as the percentage of the dosing interval spent above the minimum inhibitory concentration for beta-lactams.

A vaccine made from weakened live organisms, such as measles-mumps-rubella and varicella products. It is generally avoided in severe immunodeficiency and pregnancy and is often deferred during high-dose corticosteroid therapy.

A vaccine in which bacterial polysaccharide is covalently linked to a carrier protein, creating a T-cell-dependent response that works in infants and generates immunologic memory.

A spacer with a one-way valve placed between a metered-dose inhaler and a mouthpiece or mask. It reduces oropharyngeal deposition and improves lung delivery in children who cannot coordinate actuation with inhalation.

A pressurized canister that delivers a fixed aerosol dose with each actuation. In children it should be paired with a valved holding chamber and a well-fitted mask or mouthpiece.

Daily anti-inflammatory medication, usually an inhaled corticosteroid, prescribed for persistent asthma to reduce symptoms, exacerbations, and airway remodeling rather than to relieve acute bronchospasm.

Small-volume enteral feedings, often 10 to 20 mL/kg per day, given to premature infants to prime the gut and encourage maturation. Volumes are advanced slowly to lower the risk of necrotizing enterocolitis.

A dangerous electrolyte shift, especially hypophosphatemia, hypokalemia, and hypomagnesemia, that occurs when malnourished patients are fed aggressively. It is prevented by slow advancement and frequent electrolyte monitoring.

The recommended limit on how fast serum sodium should be raised or lowered, generally about 8 to 10 mEq/L per day for hyponatremia and 10 to 12 for hypernatremia, to avoid neurologic injury.

A method of estimating daily fluid needs from weight: 100 mL/kg for the first 10 kg, 50 mL/kg for the next 10 kg, and 20 mL/kg for each kilogram above 20.

Continuous seizure activity lasting five minutes or more, or repeated seizures without regaining consciousness. It is treated in stages with benzodiazepines, then a second-line agent such as fosphenytoin, levetiracetam, or valproate.

A water-soluble prodrug of phenytoin given intravenously for acute seizures. Doses are ordered in phenytoin equivalents, and the infusion rate is limited to prevent hypotension and arrhythmias.

A hyperglycemic emergency defined by hyperglycemia, ketonemia, and acidosis. Management uses isotonic fluids, an insulin infusion, and careful potassium replacement, with cerebral edema as the major pediatric complication.

Extra glucocorticoid given during acute illness or surgery to patients with adrenal insufficiency or chronic steroid exposure, because their adrenal glands cannot produce the normal cortisol surge.

The volume of plasma filtered by the kidneys per minute. It is low at birth and matures over the first months, so renally cleared drugs need longer intervals or smaller doses in infants.

Retrograde flow of urine from the bladder into the ureter, graded I through V. It predisposes children to pyelonephritis, and continuous antibiotic prophylaxis is considered in selected high-grade cases.

Fever in a patient whose absolute neutrophil count is below 500 cells/mm3 or expected to fall below it. It is an emergency needing prompt empiric broad-spectrum antibiotics because infection can progress rapidly.

A metabolic emergency caused by rapid breakdown of cancer cells, producing hyperkalemia, hyperphosphatemia, hyperuricemia, and hypocalcemia. Prevention and treatment rely on aggressive hydration, allopurinol or rasburicase, and close monitoring.

An X-linked enzyme deficiency that leaves red blood cells vulnerable to oxidative stress. Sulfonamides, dapsone, nitrofurantoin, primaquine, and some antimalarials can trigger hemolysis.

A fine black powder that adsorbs many drugs and toxins within the gastrointestinal tract. It is most useful within one hour of ingestion and is contraindicated with an unprotected airway or after caustic or hydrocarbon ingestion.

An opioid antagonist that rapidly reverses respiratory and central nervous system depression from opioid overdose. Repeat doses or a continuous infusion may be needed because its effect is shorter than that of many opioids.

Animal-derived antibodies that neutralize venom after envenomation. Dosing depends on envenomation severity and the specific product, and the clinician must be prepared to treat anaphylactoid reactions.

Sequential administration of a sedative and a neuromuscular blocker to secure the airway quickly and reduce aspiration risk. Drug selection depends on hemodynamic status and the clinical situation.

Sepsis with cardiovascular dysfunction, which in children often appears as compensated cold shock before hypotension develops. Treatment includes fluid boluses, early antibiotics, and vasoactive infusions.

Calculating emergency drug and fluid doses per kilogram of body weight, so an accurate or length-tape-estimated weight must be obtained immediately when caring for a critically ill child.