The most common cause of cardiac arrest in infants and young children is?

KPSC Staff Nurse - 2021

Child Health Nursing (Pediatrics)

Easy

Appeared in: KPSC Staff Nurse - 2021

Explanation

In infants and children, cardiac arrest is most often a secondary event, not a primary cardiac problem.
The underlying cause is typically progressive respiratory failure or shock, which leads to a state of profound oxygen deprivation (asphyxia).
This severe hypoxia causes the heart rate to slow down significantly (bradycardia), which eventually progresses to a full cardiac arrest, usually presenting as asystole or pulseless electrical activity (PEA).

Option A: While anaphylaxis can cause severe respiratory compromise and cardiovascular collapse leading to arrest, it is not the most frequent overall cause of cardiac arrest in the general pediatric population compared to illnesses causing respiratory failure.
Option B: Primary cardiac arrhythmias, like ventricular fibrillation, are an uncommon cause of arrest in children unless there is underlying congenital heart disease. In most pediatric arrests, arrhythmias like bradycardia are a consequence of hypoxia, not the initial cause.
Option D: A seizure itself does not directly cause cardiac arrest. A prolonged seizure (status epilepticus) can lead to apnea (cessation of breathing) and subsequent respiratory failure, but this pathway is less common than primary respiratory failure from infections, asthma, or obstruction.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Etiology of pediatric cardiac arrest as background academic context rather than a clinical decision trigger.
The key difference between pediatric and adult resuscitation is the focus. In children, the priority is supporting Airway and Breathing to prevent cardiac arrest (A-B-C approach), as per Pediatric Advanced Life Support (PALS) guidelines.
Nurses must be vigilant in identifying early signs of respiratory distress in children, such as nasal flaring, grunting, and retractions, to intervene before the child decompensates into respiratory failure.
What if the patient was a 60-year-old adult? The most common cause of sudden cardiac arrest would be a primary cardiac arrhythmia, specifically ventricular fibrillation (VF), often resulting from acute coronary syndrome.

How to Approach the Question

First, identify the key phrases in the question: "most common cause," "cardiac arrest," and the specific population, "infants and young children."
Recall the fundamental pathophysiological difference between pediatric and adult cardiac arrests. Pediatric arrests are typically secondary to respiratory issues, while adult arrests are primarily cardiac in origin.
Evaluate the options based on this principle. 'Respiratory failure' directly aligns with the known primary pathway for pediatric arrest (asphyxia).
Eliminate the other options. 'Cardiac arrhythmia' is the classic cause in adults. 'Anaphylaxis' and 'Seizure' are possible but less frequent causes of the final common pathway of respiratory failure.

Concept Tested & Keywords

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E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 609-611

E6 Ghai Essential Pediatrics(pp 26-904 of 913) p. 767-769