CPEN Environmental Emergencies 4

Question 1

A 10-year-old is found in a snowbank unconscious with a core temperature of 26°C. The child has a pulse of 28 bpm and BP 60/40. Which cardiac rhythm is MOST associated with severe hypothermia at this temperature?

Accepted Answer

Osborn (J) waves on sinus rhythm

Answer

Osborn (J) waves are pathognomonic ECG findings in hypothermia, representing abnormal ventricular repolarization at low core temperatures.

Question 2

A 16-year-old is brought to the ED after a rave event with suspected MDMA (ecstasy) use. She is hyperthermic (39.9°C), diaphoretic, and has Na of 118 mEq/L with seizures. What is the mechanism of hyponatremia in this scenario?

Accepted Answer

MDMA stimulates ADH release combined with excessive water intake

Answer

MDMA stimulates inappropriate ADH (SIADH) secretion and users often drink excessive water to prevent hyperthermia, causing dilutional hyponatremia.

Question 3

A 4-year-old is found unresponsive in an unventilated bathroom where a space heater has been running. Parents report the child 'just wouldn't wake up.' CO level is 35%. After 100% O₂ is initiated, when should hyperbaric oxygen (HBO) therapy be considered?

Accepted Answer

COHb >15% with loss of consciousness or neurological symptoms

Answer

HBO is indicated for pediatric CO poisoning with loss of consciousness, severe neurological symptoms, or high COHb (>25%), with lower thresholds for young children due to higher sensitivity.

Question 4

A 6-year-old sustained a brown recluse spider bite 72 hours ago. The wound now has a central necrotic eschar with surrounding erythema and a violaceous halo. What complication should the emergency nurse monitor for systemically?

Accepted Answer

Acute hemolytic anemia and renal failure

Answer

Systemic loxoscelism from brown recluse venom can cause massive intravascular hemolysis, hemoglobinuria, and acute renal failure in severe cases.

Question 5

An 11-year-old is brought in by parents after being found in a detached garage where a generator was running. The child is conscious but complains of headache and nausea. The father also has a headache. Which intervention should occur FIRST?

Accepted Answer

Remove both from the source and apply 100% O₂ via NRB mask

Answer

Removing the patient from the CO source and immediately applying 100% oxygen is the priority to terminate ongoing exposure and accelerate CO elimination.

CPEN - Certified Pediatric Emergency Nurse Practice Test

CPEN - Certified Pediatric Emergency Nurse Practice Test

CPEN Environmental Emergencies 4