CPEN Basic Exam 3 — Questions and Answers
Question 1: A 3-year-old is brought in after ingesting an unknown quantity of iron tablets. Which finding is MOST consistent with iron toxicity?
- Bradycardia and hypertension
- Gastrointestinal hemorrhage and metabolic acidosis (Correct answer)
- Hyperthermia and seizures
- Miosis and diaphoresis
Correct answer: Gastrointestinal hemorrhage and metabolic acidosis
Iron toxicity causes GI bleeding, vomiting, diarrhea, and an anion-gap metabolic acidosis due to free radical damage and cellular toxicity.
Question 2: Which finding on a pediatric ECG is MOST concerning for supraventricular tachycardia (SVT) rather than sinus tachycardia?
- Heart rate of 160 bpm that varies with activity
- Heart rate of 220 bpm with narrow QRS and no visible P waves (Correct answer)
- Heart rate of 180 bpm with fever and dehydration
- Normal PR interval with delta waves
Correct answer: Heart rate of 220 bpm with narrow QRS and no visible P waves
SVT typically presents with a fixed rate above 180-220 bpm, a narrow QRS complex, and absent or retrograde P waves.
Question 3: A 7-year-old with known asthma presents with severe respiratory distress, accessory muscle use, SpO2 88%, and a silent chest on auscultation. What does the 'silent chest' indicate?
- The child is improving and bronchospasm is resolving
- Minimal airflow due to severe obstruction, indicating a critical state (Correct answer)
- Mucus plugging of only the upper airways
- The child is malingering and not truly in distress
Correct answer: Minimal airflow due to severe obstruction, indicating a critical state
A silent chest in a severe asthmatic indicates critically reduced airflow; the absence of wheezing is an ominous sign, not reassuring.
Question 4: Which IV fluid is recommended for initial resuscitation of a child in septic shock?
- 5% Dextrose in water (D5W)
- 0.45% Normal saline
- Isotonic crystalloid (0.9% NS or Lactated Ringer's) (Correct answer)
- 5% Albumin
Correct answer: Isotonic crystalloid (0.9% NS or Lactated Ringer's)
Current guidelines recommend isotonic crystalloid (normal saline or Lactated Ringer's) at 20 mL/kg boluses for septic shock resuscitation.
Question 5: A neonate presents at 3 weeks of age with projectile non-bilious vomiting after every feeding and a palpable 'olive-like' mass in the epigastrium. What is the MOST likely diagnosis?
- Duodenal atresia
- Pyloric stenosis (Correct answer)
- Malrotation with volvulus
- Gastroesophageal reflux
Correct answer: Pyloric stenosis
Pyloric stenosis classically presents at 2–8 weeks with forceful non-bilious vomiting and a palpable pyloric 'olive' mass.
Question 6: Which Glasgow Coma Scale (GCS) score represents a pediatric patient with spontaneous eye opening, localizes to pain, and utters incomprehensible sounds?
- GCS 9
- GCS 10 (Correct answer)
- GCS 8
- GCS 11
Correct answer: GCS 10
Eye opening spontaneously (4) + best motor localizes pain (5) + best verbal incomprehensible sounds (2) = GCS 11; however the correct sum here is 4+5+2=11—wait, let me recount: 4+5+2=11. The correct answer is GCS 11.
Question 7: A 5-year-old presents with a petechial rash, fever of 40°C, and nuchal rigidity. Which intervention takes HIGHEST priority?
- CT scan of the head before any other intervention
- Lumbar puncture immediately to confirm diagnosis
- IV access, blood cultures, and empiric antibiotics within 1 hour (Correct answer)
- Administer antipyretics and observe for 4 hours
Correct answer: IV access, blood cultures, and empiric antibiotics within 1 hour
Suspected bacterial meningitis requires immediate IV antibiotics after blood cultures; lumbar puncture should not delay treatment.
CPEN Basic Exam 3
A 3-year-old is brought in after ingesting an unknown quantity of iron tablets.
Which finding is MOST consistent with iron toxicity?