Pediatrics Flashcards

Question

How does body composition vary over the age spectrum? (table) \*know trends, not actual numbers

Answer 1

* Higher total body water: * Water sluble drugs have a larger volume of distribution * need a larger initial dose (sch, abx) * larger distribution can delay excretion * Neonates have less fat and muscle * drugs that depend on redistribution to fat for termination of action will have prolonged effects * Protein binding: \<6 mo have less albumin and alpha-1 acid glycoprotein (AAG) * higher free-fraction of protein bound drugs * free fraction of local anesthetics will be higher (bind to AAG)

Answer 2

In general, most medications will have a **prolonged** elimination half-life in pre-term and term infants, a **shortened** half-life in children older than 2 yrs up to early teen years, and a **lengthening** of half-life in those approaching adulthood.

Answer 3

* Fetal Hgb has a lower P50 at 19 mmhg compared to 26 mmHg in adults * **LEFT shift** * Target HCT is higher in neonates d/t L shift and decreased CV reserve * minimum HCT of 40% instead of 30%

Answer 4

\*\*\* physiologic anemia at 2-3 mo

Answer 5

**4-5** ml/kg of PRBC will increase hgb about **1**g/dL

Answer 6

* Blood loss replaced at 3:1 with crystalloid * Threshold: **24-30%**, determined on individual basis * infants \<3 mo may have higher threshold d/t left shift and physiologic anemia * Consider blood sooner when: * preterm infants * term newborns * cyanotic congenital heart disease * respiratory failure needing higher O2 carrying capacity * \*\*Incidence of apnea is high in neonates and preterm infants who have hct \<30

Answer 7

* FFP if \> one blood volume is being replaced * FFP has the highest levels of citrate, so need to watch for ionized hypocalcemia and CV depression * especially in neonates and children with liver failure * Platelets replacement depends on starting plt cound and if there is oozing on the field * a child with a nml plt count usually does not need plt until EBL is \> 2 blood volumes

Answer 8

* LR for maintenancy in healthy children * glucose containing IVF may be needed in infants \< 6 mo or other risk of hypoglycemia (mitochondrial disease) * use smaller bags or buretrol * eliminate ALL air from line * TPN should not be stopped suddenly, either continue in OR or ramp it down and bridge with glucose containing fluid * Signs of dehydration: * mild: (~50 ml/kg deficit) dry mouth, poor skin turgur * moderate (~100ml/kg): mild sx plus sunkin fontanel, oliguria, tachycardia * severe (~150 ml/kg): mod sx plus sunken eyes, hypotension, and anuria

Answer 9

* uptake is more rapid d/t: * increased RR and cardiac index * large proportion of blood to VRG (heart, brain, GI, kidneys, endocrine) * reduced tissue and blood solubility in infants * alveolar ventilation to FRC ratio is 5:1 in infants vs 1.5:1 in adults * Increased incidence of hypotension in neonates and infants * Increased risk of **anesthetic overdose** in infants/toddlers * when HR starts to go down, turn down the gas! * MACS are generally higher in children

Answer 10

* Sevo * not very pungeant, does not irritate the airway * Halothane was good as well but is no longer available; caused bradycardia * Desflurane is too pungeant, can cause coughing, laryngospasm, salivation * lower solubility makes it useful for maintenance during long procedures or obese children

Answer 11

* Resp: all volatiles cause dose related resp depression and depressed response to CO2 and hypoxia * apnea worsens with higher concentration * CV: dose dep depression * sevo usually maintains or increases HR during induction * all cause prolonged QT * halothane has greatest depression of contractility * myocardial depression may be exaggerated in deonates * Emergence delirium associated with all VA * sevo \> des \> halothane

Answer 12

* Neonates have immature BBB and slower metabolism so they require lower doses * Older children and adolescents require higher doses * Propofol * **3 mg/kg** for infants \<2yr * **2.5 mg/kg** for children 6-12 years * Ketamine * 2 mg/kg IV or 4-8 mg/kg IM * plus atropine 0.02 mg/kg IM/IV (for secretions) * Etomidate (not FDA approved \< 12yr) * 0.25-0.3 mg/kg * Thiopental * neonates **3-4 mg/kg** * infants **7-8 mg/kg** * children **5-6 mg/kg**

Answer 13

* Oral midaz dosing- increases in younger pts; poor oral bioavailability and bitter taste * 18 mo-3 yr: 0.75-1 mg/kg * 3-6 yr: 0.6-0.75 mg/kg * 6-10yr: 0.5 mg/kg * Ketamine dart: * 2-5 mg/kg * onset 3-5 min and duration 30-40 min

Answer 14

* Morphine: 50-100 mcg/kg * Dilaudid: 10-20 mcg/kg * Fentanyl: 0.5-3 mcg/kg * Remi: 0.05-0.1 mcg/kg/min * Demerol: 0.25-0.5 mg/kg * Codeine: no longer prescribed as often d/t ultra rapid metabolizers having increased risk of OD--\>BLACK BOX

Answer 15

* Acetaminophen * PO: 10-15 mg/kg * IV: 15 mg/kg q 6 hours (10 min onset) * Ketorolac * 0.5 mg/kg * \*\*Caution with all NSAIDS in severe asthma

Answer 16

* NMJ not fully mature until about 2 mo * infants more sensitive to NDMB but have larger VD, so dose ends up the same as adults (except ROC) * Roc dose is 0.3 mg/kg * May see prolonged DOA d/t immature kidney and liver * Higher sch dose needed in neonateds d/t larger VD * Sch only used in RSI or laryngospasm (bradycardia, hyperkalemia, MH) * Neostigmine dose 40% lower than adult (0.2-0.4 mcg/kg

Answer 17

* LA absorption increased d/t increased CO and local blood flow (2-3x greater in infants than adults) * Epi can still slow down uptake * Plasma AAG is low at birth and does not reach adult levels before 1 yr * Free fraction of all LA is increased in infants

Pediatrics Flashcards

(43 cards)