ITE CA-2 Pediatric Anesthesia

Question 1

Pre-term baby resp distress with positive meconium at birth

Answer 1

Nasal CPAP has lowered the incidence of BPD when compared to intubation and ventilation in neonates

Nasal CPAP decreases atelectasis and maintains recruitment.

Advantages of the nasal route are that neonates are obligate nose-breathers (until 5 months of age) and a full facemask may cause facial/nasal pressure necrosis. Also, there is some evidence that nasal CPAP is superior to intubation and mechanical ventilation in preventing broncho-pulmonary dysplasia.

Question 2

Neonates lung volumes

Answer 2

Neonates have higher closing capacity and a lower functional reserve capacity compared to adults

Functional residual capacity is lower in neonates, but this increases over the first few days of life and reaches adult levels at about day 4.

Question 3

Symptomatic tachy in a kid with QRS 0.11

Answer 3

Wide complex tachycardia with evidence of cardiopulmonary compromise should be treated with synchronized cardioversion (0.5-1 J/kg).

Wide complex QRS is defined as greater than 0.09 seconds duration in children.

Question 4

Child asymptomatic tachy wide QRS

Answer 4

If the patient with a wide complex tachycardia is hemodynamically stable without evidence of cardiopulmonary compromise then adenosine may be administered. The AHA also recommends consultation for possible amiodarone or procainamide administration.

Question 5

Peds narrow complex tachy

Answer 5

Narrow complex tachycardia can be divided into probable sinus tachycardia versus probable supraventricular tachycardia (SVT). P-waves are present in sinus tachycardia and HR is typically less than 220/min for an infant and 180/min for children (150/min for adults). Supraventricular tachycardia has either absent P-waves or morphologically abnormal P-waves with fixed HR typically > 220 for infants and > 180 for children. Vagal maneuvers and/or adenosine are recommended as first line therapy for SVT. If adenosine is ineffective or IV/IO access is not available, then proceed with synchronized cardioversion. Sinus tachycardia therapy includes treating the cause.

Question 6

Differences for spinal between infants and adults

Answer 6

Spinal anesthesia in infants has many differences compared to adults including increased speed of onset, decreased duration of action, lack of hemodynamic collapse, and increased block spread owing to anatomic differences in the spinal cord

Question 7

Sign of high spinal in infant

Answer 7

Apnea

Question 8

CSF volume and distribution

Answer 8

CSF volume (10 mL/kg in neonates vs 4 mL/kg in infants vs 3 mL/kg in children vs 2 mL/kg in adults) and distribution (50/50 split between brain and spinal cord and 70/30 split in adults)

Question 9

Factors that contribute to closure of the ductus arteriosus include

Answer 9

Factors that contribute to closure of the ductus arteriosus include decrease in PVR, increase in SVR, increase in PaO2 > 50 mmHg (causes arterial smooth muscle of the ductus to contract), normocarbia, and euvolemia.

Question 10

When does ductus arteriosus close? Foramen ovale?

Answer 10

Fetal PVR is high due to lack of oxygen in the alveoli. With the first breath of life, alveoli fill with oxygen and the infant’s PVR decreases. As PVR decreases, SVR increases and the ductus arteriosus functionally closes within the first 12-24 hrs. As a result, more blood flows through the lungs and into the left atrium. This results in functional closure of the foramen ovale. It will take several months for the ductus arteriosus and the foramen ovale to close

Question 11

If the ductus arteriosus does not functionally close within __ days of birth, it is considered a PDA.

Answer 11

If the ductus arteriosus does not functionally close within 4 days of birth, it is considered a PDA. Premature infants with birth asphyxia and neonatal respiratory distress syndrome are the most likely patients to have complications from a PDA. The diagnosis of persistent fetal circulation or persistent pulmonary hypertension of the newborn can be made by noting a > 20 mmHg difference in PaO2 between preductal (e.g. right radial artery) and postductal (e.g. umbilical, posterior tibial, or dorsalis pedis) arterial lines

Question 12

The diagnosis of persistent fetal circulation or persistent pulmonary hypertension of the newborn can be made by

Answer 12

If the ductus arteriosus does not functionally close within 4 days of birth, it is considered a PDA. Premature infants with birth asphyxia and neonatal respiratory distress syndrome are the most likely patients to have complications from a PDA. The diagnosis of persistent fetal circulation or persistent pulmonary hypertension of the newborn can be made by noting a > 20 mmHg difference in PaO2 between preductal (e.g. right radial artery) and postductal (e.g. umbilical, posterior tibial, or dorsalis pedis) arterial lines

Question 13

Neonatal resuscitation

Answer 13

If a neonate’s heart rate is less than 60 bpm for greater than 30 seconds despite adequate ventilation with supplemental oxygenation, chest compressions are indicated. Chest compressions should be performed in a 3:1 ratio with ventilation at a rate of 120 events per minute (i.e. 90 chest compressions and 30 breaths total per minute), and full chest recoil should be allowed after each compression. This should continue until the neonate’s heart rate is > 60 bpm.

Question 14

Pyloric stenosis acid base presentation

Answer 14

Pyloric stenosis commonly presents as a hypochloremic, hypokalemic, metabolic alkalosis with compensatory respiratory acidosis. Elevated serum bicarbonate is often present along with increased urine specific gravity and decreased urine chloride.

TrueLearn Insight : Metabolic alkalosis must be corrected before a pyloromyotomy in order to prevent postoperative central apnea due to CSF alkalosis. Pyloric stenosis and pyloromyotomies are therefore NOT surgical emergencies.

Question 15

Nonshivering thermogenesis
what is it
what triggers it
what inhibits it

Answer 15

Nonshivering thermogenesis is the major source of heat production in neonates and infants. It is triggered by norepinephrine, glucocorticoids, and thyroxine. It is inhibited by inhalational anesthetics and β-blockers.

Question 16

pyloric stenosis acid/base disturbance

Answer 16

Pyloric stenosis commonly presents as a hypochloremic, hypokalemic, metabolic alkalosis with compensatory respiratory acidosis. Elevated serum bicarbonate is often present along with increased urine specific gravity and decreased urine chloride.

TrueLearn Insight : Metabolic alkalosis must be corrected before a pyloromyotomy in order to prevent postoperative central apnea due to CSF alkalosis. Pyloric stenosis and pyloromyotomies are therefore NOT surgical emergencies.

Question 17

Anesthetic management for congenital diaphragmatic hernia in a newborn

Answer 17

CDH should be managed using lower tidal volume ventilation with permissive hypercapnia (PaCO2 up to 65 mm Hg), maintenance of SpO2 90-95% preductally, maintenance of normothermia, and with prevention of worsening pulmonary hypertension

Question 18

most common croup organism

Answer 18

parainfluenza

Question 19

Caudal blockade dosing

Answer 19

Sacral 0.5 ml/kg
Lumbar 1 ml/kg
Mid thoracic 1.25 ml/kg

Question 20

steeple sign

Answer 20

croup

Question 21

barking cough

Answer 21

croup

Question 22

treatment for croup

Answer 22

racemic epi

Question 23

thumbprint sign

Answer 23

epiglottitis

Question 24

fever, increased secretions, resp failure, tripod position

Answer 24

epiglottitis

Question 25

Retinopathy of prematurity 
most common in 
most cited cause
course of disease
treatment

Answer 25

Retinopathy of prematurity is most common in infants less than 1200 grams with a most cited cause of hyperoxia. Most of those affected have spontaneous regression to normal vision; and a general anesthetic is necessary for treatment as a still surgical field is needed.

Question 26

Children oxygen consumption

Answer 26

Children, especially infants, desaturate quickly due to increased oxygen consumption (up to 7-8 mL/kg/min).

Question 27

The most common causes of postintubation croup

Answer 27

The most common causes of postintubation croup are subglottic injury and edema associated with traumatic intubation, an oversized endotracheal tube, or an overinflated ETT cuff. The latter is likely if no air leak exists at 30-40 cm H2O with positive airway pressure.

Question 28

med to prevent postintubation croup

Answer 28

Dexamethasone (0.5 mg/kg IV, max 10 mg) has been shown to be effective in reducing postintubation croup.

Question 29

Treatment for postintubation croup

Answer 29

Severity of postintubation croup can be measured by the Clinical Croup Score which can help dictate treatment. Mild postintubation croup can be treated with cool, humidified mist, while moderate-severe (7+ score) symptoms benefit from nebulized racemic epinephrine followed by 4-5 hours of monitoring to watch for rebound effects.

Question 30

Ear tubes in kid with trisomy 21

Answer 30

Myringotomy and tube placement often involves a rapid inhaled anesthetic with avoidance of premedication, intubation, and intravenous catheter placement. Instead, intramuscular, intranasal, oral, and rectal routes for medication administration are used. However, the anesthesiologist should be prepared to alter these plans for patients with complex medical problems such as patients with Down syndrome. For patients who have inflexible cervical spines or cervical spines at risk for atlantoaxial instability, tilting of the bed should be employed, and excess movement of the neck should be avoided. Supraglottic devices may be needed, and an intravenous catheter should be considered in Down syndrome patients presenting for this procedure.

Question 31

Define fetal acidemia

Answer 31

Scalp blood gas pH less than 7.2
Or
Lactate greater than 4.8

Question 32

Pediatric airway
tongue size
collapsibility
position of the larynx
shape of epiglottis
vocal cords
narrowest

Answer 32

Tongue size is proportional and not a cause of obstruction

The pediatric airway is characterized by greater collapsibility,
more cephalad position of the larynx,
omega-shaped epiglottis (stubby not flat),
slanted vocal cords (such that the anterior insertion is lower (caudad) compared with the posterior insertion), and
functionally narrow subglottic region.

Question 33

Larynx position
infant
adult

Answer 33

infant C3-C4

adult C4-5

Question 34

Define thermal neurtral zone
What is it for a naked term infant

Adult?

Answer 34

The thermal neutral zone is the temperature at which normothermia is achieved with basal metabolic rate. For a naked, full-term newborn the thermoneutral zone is 32-35degC.

Adult 26-28

Question 35

Ideal leak pressure uncuffed tube peds patients

Answer 35

The ideal leak pressure of an uncuffed ETT in pediatric patients is 20-30 cm H2O. If a leak pressure >40 cm H2O is measured, the ETT should be replaced with a smaller size.

Question 36

Which of the following is an appropriate initial intravenous fluid bolus for a 12 kg child who presents with vomiting, oliguria, and weak pulses?

Answer 36

Initial intravenous fluid resuscitation in children should be accomplished with 20 mL/kg of an isotonic salt solution without potassium supplementation.

Solutions containing dextrose (C,D,E) are considered maintenance fluids and should be administered after initial resuscitation is completed. Potassium (E) should not be administered until adequate urine output (≥0.5-1 mL/kg/hr) has been established in order to prevent life-threatening hyperkalemia.

Question 37

Up until __ weeks postconceptual age, neonates should be monitored overnight following a general anesthetic to avoid episodes of apnea and bradycardia.

Answer 37

Up until 60 weeks postconceptual age, neonates should be monitored overnight following a general anesthetic to avoid episodes of apnea and bradycardia.

Question 38

prophylactic treatments for apnea of prematurity

Answer 38

caffeine or theophylline (increase central resp drive)

Question 39

Minimum age to start anxiolysis in peds

Answer 39

Preoperative pharmacologic anxiolysis is not usually necessary until the development of separation anxiety, which normally occurs after 6 months of age.

Question 40

Risk factors for postoperative apnea

Protective factor

Answer 40

Risk factors for postoperative apnea include
use of general anesthesia or regional anesthesia with IV sedation,
a history of prematurity,
PCA < 60 weeks (especially < 42-44 weeks),
a history of apnea, and
anemia.

Being small for gestational age has been found to be somewhat protective against postoperative apnea.

Question 41

infant diaphragm

Answer 41

due to the decreased proportion of diaphragmatic type I muscle fibers, infants are more susceptible to early fatigue of respiratory muscles.

Question 42

Transient anemia of the newborn what age

Answer 42

Often a newborn experiences a mild and transient anemia at 8-12 weeks of life.

Question 43

The subglottic trachea is ____ in shape compared to adults.

Answer 43

The subglottic trachea is elliptical in shape compared to adults.

Question 44

timing of foramen ovale closure

Answer 44

Following the neonate’s first breath, the compression of the pulmonary vasculature is relieved and the pulmonary vascular resistance is subsequently lowered. The functional closure of the foramen ovale occurs within hours of birth while anatomic closure occurs within the first year.

Question 45

most important factor in the closure of the ductus arteriosus.

Answer 45

Oxygen tension is the most important factor in the closure of the ductus arteriosus.

Question 46

Bronchopulmonary dysplasia
is a sequela of what
seen in infants less than what age
chronic or acute
what part of the lungs

Answer 46

Bronchopulmonary dysplasia, a sequela of respiratory distress syndrome, is most often seen in preterm infants less than 32 weeks gestation and is a chronic disease of the airways and lung parenchyma.

Many patients with bronchopulmonary dysplasia benefit from bronchodilator treatment prior to a general anesthetic.

Question 47

when does the ductus arteriosus close

Answer 47

The DA is functionally closed by 12 hours postnatally, but not anatomically closed for a few weeks.

Question 48

how keep PDA open

Answer 48

Prostaglandin E2 (PGE2) is used to maintain a PDA, but there are a few complications to watch for. PGE2 is associated with hypotension and apnea in the neonate.

Question 49

Peds ETT size

Answer 49

Cole formula: internal diameter of uncuffed ETT = (Age / 4) + 4

The Cole formula is an age-based formula commonly used to calculate the optimal size (and internal diameter) of uncuffed endotracheal tubes for children between the ages of 2 and 8 years old.

Question 50

Anesthetic management for a foreign object in the proximal tracheobronchial tree

Answer 50

Anesthetic management for a foreign object in the proximal tracheobronchial tree, as in this question, includes maintenance of spontaneous respiration on induction, which will prevent the need for positive pressure ventilation. Positive pressure ventilation may push a foreign body more distal in the airways, making retrieval more technically difficult and increasing the risk of associated complications.

Question 51

neonates cyp2d6 activity

Answer 51

decreased

increases after the first 2 weeks of life

Question 52

CYP3A4 in infants

Answer 52

Another cytochrome enzyme, CYP3A4, converts opioids to inactive metabolites, such as fentanyl to norfentanyl and tramadol to nortramadol. CYP3A4 is very low in preterm and term neonates then surges in the first year of life. Hence, this mechanism makes these patients more susceptible to oversedation and respiratory depression.

Question 53

UGT2B7 in infants

Answer 53

Lastly, UGT2B7 converts morphine to metabolites, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G), which are then able to be renally excreted. The levels of UGT2B7 are low after birth until 10 days of age, and morphine should be reduced 50% to achieve the same analgesic effects on a kilogram-per-body-weight basis.

Question 54

Risk factors for adverse events during pediatric sedation include

Answer 54

Risk factors for adverse events during pediatric sedation include ASA physical status 3 or greater, obesity, age less than 3 months, airway related procedures, and multiple drug combinations.

Question 55

short and long term risks of anesthesia in children with URIs

Answer 55

Children with URIs are at increased risk for perioperative pulmonary complications including coughing, laryngospasm, bronchospasm, transient periods of hypoxia, croup, and pneumonia. However, long-term outcome studies do not show any significant difference in long-term sequelae in pediatric patients with or without URIs.

Question 56

succ in strabismus surgery

Answer 56

Succinylcholine should be avoided in patients undergoing strabismus surgery due to its effects on forced duction testing

Question 57

The first sign of total spinal anesthesia in neonates is typically ______
. Hemodynamic and autonomic effects are generally ______.

Answer 57

The first sign of total spinal anesthesia in neonates is typically respiratory depression or apnea. Hemodynamic and autonomic effects are generally minimal.

Question 58

The addition of a humidifier to the anesthesia circuit can significantly increase Vd/Vt in pediatric patients.

Answer 58

The addition of a humidifier to the anesthesia circuit can significantly increase Vd/Vt in pediatric patients.

Question 59

Benefits of parental presence for induction of anesthesia (PPIA)

Answer 59

Benefits of PPIA include a decreased need for premedication, decreased anxiety in the child, and increased anesthetic compliance. However, PPIA is less effective than premedication alone in reducing anxiety and increasing compliance in pediatric patients.

Parental presence for induction of anesthesia may be beneficial when a child is anxious and the parent is calm. There is no proven benefit to PPIA when a child is calm and a parent is anxious.

Question 60

Hypoplastic left heart syndrome

Answer 60

Hypoplastic left heart syndrome is associated with ASDs, stenotic or atretic mitral and aortic valves, a hypoplastic left ventricle, a hypoplastic ascending aorta, and a PDA.

Question 61

The classic laboratory findings in patients with pyloric stenosis who present several weeks into the disease course

Answer 61

The classic laboratory findings in patients with pyloric stenosis who present several weeks into the disease course are hypokalemia, hyponatremia, and hypochloremic metabolic alkalosis with compensatory respiratory acidosis.

Question 62

pyloric stenosis post op apnea mechanism

Answer 62

In children with pyloric stenosis, serum alkalosis leads to CSF alkalosis. Even with correction of serum alkalosis (pH and bicarbonate), the CSF acid-base imbalance can persist. This CSF alkalosis can lead to postoperative apnea via the central control of ventilation.

Question 63

infants water needs and why

Answer 63

Term infants have a greater basal water requirement compared to adults due to their greater metabolic requirement.

Question 64

infant GFR

Answer 64

Infants have a lower glomerular filtration rate (GFR) compared to adults.

Question 65

Infants total body water

Answer 65

Infants have a greater percentage of total body water (TBW) compared to an adult

Question 66

Infants and small children dosing of muscle relaxants.

Answer 66

Infants and small children have larger extracellular fluid volumes by percentage of TBW and therefore require larger weight-based dosing of muscle relaxants.

Question 67

Postoperative in-hospital monitoring of premature infants after GA or regional anesthesia with sedation

Answer 67

Postoperative in-hospital monitoring of premature infants for 12-24 hours after GA or regional anesthesia with sedation should be considered in infants before 44-60 weeks PCA without a history of apnea/bradycardia or any age in which an apnea/bradycardia event has occurred within the previous six months. Risks for postoperative apnea include GA, IV sedation, and anemia. The risk of postoperative apnea is inversely proportional to the gestational age and PCA. Being small for gestational age appears to provide some protection against postoperative apnea. General anesthesia, anemia, and PCA < 44-60 weeks at the time of surgery are all INDEPENDENT risk factors for postoperative apnea.

Question 68

If an infant has a history of apnea and bradycardia, it is advocated that there should be a _____ interval free from any events prior to proceeding with elective outpatient surgery.

Answer 68

If an infant has a history of apnea and bradycardia, it is advocated that there should be a six-month interval free from any events prior to proceeding with elective outpatient surgery.

Question 69

respiratory stimulant meds for prophylactic apneic episodes

Answer 69

Regardless of the postoperative plan, some advocate the administration of a respiratory stimulant, such as IV caffeine (10 mg/kg) or aminophylline, as a prophylactic measure to prevent apneic episodes.

Question 70

Apneic episodes in babies

Answer 70

Apnea is defined as the cessation of breathing >10 or >15 seconds (depending on source), or for any duration if accompanied by cyanosis and bradycardia.

Note, periodic breathing is regular breathing interrupted by short pauses or apnea lasting 5-10 seconds without cyanosis or bradycardia. This is a normal variant and may be present in both full term and preterm neonates.

Question 71

most effective medication to prevent post operative nausea and vomiting in children

Answer 71

Ondansetron is the most effective medication to prevent post operative nausea and vomiting in children

Question 72

Risk factors of PONV in children

percentages with how many factors

Answer 72

Many factors increase the risk of PONV in pediatric patients including patient age (> 3 years old), duration of surgery (> 30 minutes), type of procedure (strabismus repair and adenotonsillectomy increase risk of PONV), as well as patient and family history of PONV. Zero, 1, 2, 3, or 4 of these risk factors impart a risk of postoperative vomiting of 9%, 10%, 30%, 55%, and 70% respectively in pediatric patients. Males are at the same risk for PONV as are females until puberty.

Question 73

estimate blood volume by age

Answer 73

Age Group	Blood Volume (mL/kg)
Premature infant	90-105
Full term newborn	80-90
Infant (3 months - 1 year)	70-80
Child (1-12 years)	70-75
Adult Male	65-70
Adult Female	60-65

Question 74

Emergence delirium
most common age range
duration
risk factors
sequelae

Answer 74

Emergence delirium is a state of extreme excitement that occurs more frequently in children between the ages of 1 to 4. It can also occur in older children, adolescents, and adults. Emergence delirium generally lasts less than 30 minutes and treatment is supportive. Use of less soluble volatile anesthetics (e.g. desflurane, sevoflurane) is strongly associated with the development. Other factors for the development of emergence delirium include preoperative anxiety, postoperative pain, and stressful recovery environments.

Children who have emergence delirium are more likely to have new-onset postoperative maladaptive behavioral changes.

Question 75

Pharm treatment for emergence delirium

Answer 75

A rapidly acting opioid (e.g. fentanyl) is the first choice. Dexmedetomidine can be used to help decrease symptoms. A dose of physostigmine for suspected anticholinergic effects from scopolamine or atropine may be given if appropriate. If the symptoms are severe and the patient is in danger then administration of a stronger sedative may be necessary; propofol is the commonly used in this situation however apnea is a risk and preparation to treat this must occur prior to administration. If intravenous access has been lost, haloperidol or ketamine may be administered via the intramuscular route.

Question 76

prevention of emergence delirium

Answer 76

Prevention of emergence delirium may be multifactorial. Use of intravenous anesthesia may decrease the risk. Other medications that have been trialed include midazolam, clonidine, dexmedetomidine, fentanyl, and physostigmine. Midazolam is the most used agent, but the effects on emergence delirium are conflicting with variable results in different studies. A large Cochrane meta-analysis found that neither premedication with midazolam in the preoperative period nor parental presence at emergence decreased the risk. Preoperative coaching and education of both the patient and the parents, if the patient is young, can help to decrease the risk. Multimodal analgesia can help decrease postoperative pain and potentially reduce emergence delirium risk.

Question 77

Patients with Treacher Collins syndrome have associated conditions including

Answer 77

Patients with Treacher Collins syndrome have associated conditions including hearing loss, obstructive sleep apnea, and sudden infant death syndrome (SIDS). However, they are not associated with developmental delay or congenital heart defects. These patients are notoriously difficult to ventilate and intubate, and supraglottic airways may provide adequate ventilation or a conduit for intubation.

Treacher Collins syndrome is also known as mandibulofacial dysostosis.

Question 78

incidence increasing or decreasing in peds
DMI
DMII

Answer 78

The incidence of both types 1 and 2 diabetes mellitus is increasing in children.