EDAIC Pediatric and Neonatal Anesthesia 5 — Questions and Answers
Question 1: A preterm neonate undergoing laser treatment for retinopathy of prematurity (ROP) requires anesthesia. Which anesthetic concern is MOST specific to this procedure?
- Risk of malignant hyperthermia from volatile agents
- Hyperoxia worsening ROP progression (Correct answer)
- Hypothermia from prolonged exposure to operating room temperature
- Increased intracranial pressure from airway manipulation
Correct answer: Hyperoxia worsening ROP progression
Excessive supplemental oxygen (hyperoxia) during anesthesia can worsen ROP; oxygen saturation targets of 90–95% are typically maintained to minimize retinal injury.
Question 2: Which of the following best describes the hepatic clearance of drugs in neonates compared to older children?
- Neonates have higher hepatic clearance due to proportionally larger liver
- Neonates have reduced clearance due to immature cytochrome P450 enzyme activity (Correct answer)
- Neonates and older children have equivalent hepatic drug clearance per kg
- Hepatic clearance is irrelevant in neonates as renal excretion predominates
Correct answer: Neonates have reduced clearance due to immature cytochrome P450 enzyme activity
Cytochrome P450 enzyme systems (especially CYP3A4) are markedly immature at birth, significantly reducing hepatic drug clearance in neonates.
Question 3: During tracheoesophageal fistula (TEF) repair in a neonate, which intraoperative event should prompt the anesthesiologist to check for a right-sided intubation?
- Sudden decrease in ETCO2
- Sudden deterioration of SpO2 with decreased chest rise on the left (Correct answer)
- Development of ST changes on ECG
- Increase in peak airway pressure with improved SpO2
Correct answer: Sudden deterioration of SpO2 with decreased chest rise on the left
Surgical manipulation can advance the ETT into the right mainstem bronchus; left-sided decreased breath sounds with falling SpO2 indicates endobronchial intubation.
Question 4: What is the most appropriate initial management of laryngospasm in a pediatric patient?
- Immediate IV succinylcholine 2 mg/kg
- Vigorous bag-mask ventilation with high flow oxygen
- Positive pressure via tight-fitting mask with jaw thrust (Larson's maneuver) (Correct answer)
- Emergency cricothyroidotomy
Correct answer: Positive pressure via tight-fitting mask with jaw thrust (Larson's maneuver)
Immediate application of CPAP with jaw thrust (Larson's maneuver targeting the laryngospasm notch) is the first-line treatment for laryngospasm, breaking the reflex before resorting to medications.
Question 5: In a child with pulmonary hypertension undergoing cardiac catheterization, which intraoperative trigger should be MOST aggressively avoided?
- Hypothermia below 35°C
- Hypercapnia and acidosis (Correct answer)
- Inhalation induction with sevoflurane
- Dexmedetomidine infusion
Correct answer: Hypercapnia and acidosis
Hypercapnia and acidosis are potent pulmonary vasoconstrictors that can precipitate acute right ventricular failure in children with pulmonary hypertension.
Question 6: What is the key pharmacokinetic difference of local anesthetics in neonates that increases toxicity risk compared to older children?
- Higher plasma concentrations due to immature renal elimination
- Lower alpha-1 acid glycoprotein levels leading to higher free drug fractions (Correct answer)
- Faster absorption from tissue depot sites
- Reduced sensitivity of sodium channels to local anesthetic blockade
Correct answer: Lower alpha-1 acid glycoprotein levels leading to higher free drug fractions
Neonates have lower plasma levels of alpha-1 acid glycoprotein (AAG), resulting in a higher free (unbound) fraction of local anesthetic available to cause systemic toxicity.
Question 7: A child with Down syndrome (trisomy 21) is scheduled for elective surgery. Which preoperative assessment is MOST important from an anesthetic standpoint?
- Thyroid function tests
- Atlantoaxial instability assessment (Correct answer)
- Echocardiogram for congenital heart disease
- Renal function panel
Correct answer: Atlantoaxial instability assessment
Atlantoaxial instability occurs in 10–20% of children with Down syndrome and poses a risk of spinal cord injury with neck manipulation during intubation.
EDAIC Pediatric and Neonatal Anesthesia 5
A preterm neonate undergoing laser treatment for retinopathy of prematurity (ROP) requires anesthesia.
Which anesthetic concern is MOST specific to this procedure?