Peds Summary

Question 1

SBE propylaxis

Answer 1

• Should be given 30-60 minutes prior
• Cefazolin 50 mg/kg or amoxicillin or if true penicillin allergy- doxycycline
• Patients should get it for following risk factors & procedure type: previous endocarditis, CHD repair within 6 months or no previous repair, cardiac transplants with valvopathy, synthetic valve repair
• procedure type: dental exam with abscess, tooth extraction or moving gingiva, respiratory procedure where incision is made, cardiac procedure, infectious skin or neuromuscular procedure
• Not given with bronchoscopy without biopsies, GI or GU procedure (if infectious treat with normal abx.), routine dental cleaning

Question 2

Apnea of prematurity

Answer 2

• inversely proportional to postconceptual age (= conceptual age + postnatal age)
• apnea >15 seconds is both central and obstructive
• may see bradycardia & desaturations
• Risk factors: low birth weight, anemia, hypothermia, sepsis, neurological abnormalities, & type of surgery
• Risk reduction occurs after 44 weeks PCA (but still exists)
• Can continue to occur for 48 hours postop (even with regional!)
• Management includes: in house admission for all premature infants <60 weeks PCA, deferment of elective surgery until >44-50 weeks PCA, IV caffeine, Nasal CPAP or intubation

Question 3

Maximum allowable blood loss is:

Answer 3

EBV (100 mg/kg for infants) x (Starting Hct- allowable Hct)/ Starting Hct

Question 4

NPO guidelines for peds:

Answer 4

2 hours- clear liquids
4 hours- breast milk
6 hours- nonhuman milk, formula

Question 5

Fetal circulation is characterized by:

Answer 5

high PVR secondary to fluid filled lungs
low SVR secondary to large surface area of placenta
most oxygenated blood from the umbilical vein perfuses the brain & heart by shunting across the liver via the ductus venosus and shunting across the right heart via the foramen ovale

Question 6

The effect of _________* and __________ produce an oxygen carrying capacity in the fetus that is nearly equal to adults

Answer 6

left shifted Hgb F & polycythemia

Question 7

Fetal circulation path:

Answer 7

2 arteries bring blood to placenta
1 umbilical vein brings blood (mostly to IVC) as it bypasses the liver via the venosus ductus
right atrium through foramen ovale to left atrium to left ventricle through aorta
also have deoxygenated blood returning from brain through SVC to right atrium and then right ventricle, goes through PA and bypasses lungs through the ductus arteriosus

Question 8

Circulatory changes at birth include:

Answer 8

lungs fill with gas & pulmonary vascular decreases
decreased PVR so blood flows to lungs & pressure in LA increases over RA pressure closing the atrial septum over the foramen ovale
Placental clamp increases systemic vascular resistance Increase in SVR & aortic pressure > pulmonary artery pressure results in reverse flow through ductus arteriosus

Question 9

A _________ causes closure of the ductus arteriosus

Answer 9

decrease in prostaglandins

Question 10

Permanent anatomic closure of the ductus arteriosus is usually complete in

Answer 10

5-7 days

Question 11

A patent ductus arteriosus results in

Answer 11

congestive heart failure & low diastolic pressure

Question 12

Preductal versus postductal monitoring.

Answer 12

Preductal- right hand (oxygenated)
postductal- lower limb (may be less oxygenated)
if you see a drop in the postductal sat this means you have a change in your pHTN and should deepen your anesthetic

Question 13

Describe the difference between the pediatric & adult airway.

Answer 13

tongue- bigger
position of larynx- higher
epiglottis- omega shaped, more difficult to lift
subglottic- smaller & oblong shaped**
vocal cords- lower (caudad) anterior attachment (aka a sharper diagonal line)
trachea- shorter
easier with a straight blade!

Question 14

Subglottic stenosis:

Answer 14

90% of acquired subglottic stenosis are the result of ETT & prolonged intubation
often requires placement of a smaller ETT

Question 15

Production of surfactant begins between

Answer 15

23 to 24 weeks of gestation**

Question 16

_____ remains constant throughout development.

Answer 16

Vt/kg****

Question 17

Babies have lower numbers of (chest wall tips)

Answer 17

type 1 muscle fibers
chest wall is more horizontal & pliable
more prone to fatigue & apnea for these reasons

Question 18

Anytime a baby experiences bradycardia & apnea

Answer 18

think airway!

Question 19

Subglottic stenosis is

Answer 19

90% the result of prolonged intubation with too large of an ETT
often requires placement of smaller ETT

Question 20

Bronchopulmonary dysplasia is

Answer 20

a form of chronic lung disease that occurs in patients who have survived severe neonatal lung disease
similar to emphysema for adults
cause is uncertain but may be related to frequent collapse & reopening of alveoli
-infants may require supplemental O2, develop lower airway obstruction & air trapping, Co2 retention, atelectasis, bronchiolitis, & bronchopneumonia
-ventilation strategies include small tidal volumes (4-6 mL/kg), greater respiratory rates, PEEP, and minimized inspired oxygen concentration

Question 21

Retinopathy of prematurity is:

Answer 21

the arrest of normal retinal vascular development in exchange for neovascularization and fibrous tissue formation in the retina
-can lead to retinal detachment & fibrosis
-associated with low birth weight, oxygen exposure, prematurity, apnea, blood transfusions, sepsis, & CO2
Anesthesia saturation goal is 90-94%**
fluctuating oxygen levels may be more damaging than high oxygen tensions

Question 22

Normoglycemia for infants is

Answer 22

45 to 90 mg/dL**
should be maintained on IV dextrose when NPO & must closely watch
predisposed to hypoglycemia during stress (surgery)

Question 23

Four routes of heat loss include

Answer 23

radiation > convection > evaporation > conduction
pediatric patients have increased risk for heat loss
utilize non-shivering thermogenesis during the first 3 months of life

Question 24

Prematurity and the renal system:

Answer 24

significantly reduced ability to compensate for large swings in volume
glomeruli continue to form postnatally until approximately 40 days
renal clearance of drugs is reduced- ability to handle free water & solute loads may be impaired in neonates; half-life of medications will be prolonged
reduced proximal tubular reabsorption of sodium & water

Question 25

Prematurity & the hepatic system:

Answer 25

at term, functional maturity of the liver is somewhat incomplete
cytochrome p450 reaches ~50% of adult values at birth
phase II are impaired until ~1 year of age
limited glycogen stores
limited ability to handle large protein loads
reduced albumin synthesis- greater levels of unbound drugs

Question 26

NEC:

Answer 26

illness found in low birth weight infants with high mortality

• morbidity associated with NEC includes short bowel syndrome, sepsis, & adhesions
• cause is uncertain & multifactorial
• early signs include abdominal distension, bloody diarrhea, temperature instability & lethargy
• bowel perforation & free air within the abdomen are indication for the urgent/emergent surgery for resection of dead bowel
• infants generally present with metabolic and hematologic abnormalities (hyperkalemia, hyponatremia, hyper or hypoglycemia, metabolic acidosis, coagulopathy/DIC, anemia)
• surgical emergency
• aspiration risk so need RSI
• narcotic technique with muscle relaxation- avoid nitrous oxide
• vascular access x 2 & a-line
• vasopressor infusions
• large fluid loss & blood loss
• Correct electrolytes & glucose

Question 27

Take home point for inguinal hernia repair:

Answer 27

if inadequate depth of anesthesia, patient may have laryngospasm when the surgeon pulls on the hernia sac

Question 28

Congenital diaphragmatic hernia

Answer 28

anatomic defect permits intrusion of abdominal contents into thoracic cavity*
early (worse outcomes) vs. late (better outcomes)
infants with the Bochdalek-type hernia* are more likely to have concurrent birth defects & chromosomal abnormalities
Hallmark signs: hypoxia, scaphoid abdomen, & evidence of bowel in thorax
CDH is potentially lethal due to pHTN, pulmonary hypoplasia, and associated cardiac or congenital defects***
may require ECMO, HFOV, & inhaled nitric oxide
avoid mask venitlation to limit gastric insufflation
supine or lateral
pre & post ductal monitoring
reactive pulmonary vasculature
PIV x 2, CVC, a-line
EBL 5-10 mL/kg
paralysis, narcotics & limited inhalation agent
avoid nitrous oxide

Question 29

Omphalocele & gastroschisis

Answer 29

omphalocele has associated genetic, cardiac, urologic, & metabolic abnormalities
viscera emerge from the umbilicus & are covered with a membranous sac
Management includes reduction of fluid loss*** from exposed visceral surfaces
Criteria for aborting primary closure: end tidal Co2 >50 and max ventilatory pressure >35

Question 30

TEF takeaways

Answer 30

most common type is EA with distal TEF
maintain spontaneous ventilation while intubating b/c don’t want to put air into the belly
confirm ETT placement between fistula & carina
Pros & cons to leaving intubated or extubating right away

Question 31

Oxygen consumption of an average neonate is

Answer 31

5-8 mL/kg/min

Question 32

Fetal hemoglobin has an increased affinity for

Answer 32

oxygen and can reduce oxygen release of hemoglobin to the tissues

Question 33

Temperature regulation requires

Answer 33

warming the room temperature & active warming