Which clinical indicator is the nurse most likely to identify when collecting the history and physical assessment of a patient with complete heart block?

Appeared in: ISRO 2024

Explanation

Complete heart block involves a total dissociation between atrial and ventricular contractions.
This results in the ventricles beating at a very slow escape rhythm (20-40 bpm), a condition known as severe bradycardia.
The severe bradycardia drastically reduces cardiac output, leading to decreased blood flow to the brain (cerebral hypoperfusion).
This lack of adequate brain perfusion causes syncope, which is a transient loss of consciousness.
These syncopal episodes related to heart block are specifically termed Stokes-Adams attacks.

Option B: Headache is a non-specific symptom that can be caused by numerous conditions and is not a primary or hallmark indicator of complete heart block.
Option C: Tachycardia is a heart rate greater than 100 bpm. Complete heart block is defined by severe bradycardia (a very slow heart rate), making tachycardia the opposite of the expected finding.
Option D: Hemiparesis (weakness on one side of the body) is a focal neurological deficit. It is a classic sign of a cerebrovascular accident (stroke), not a direct symptom of a cardiac arrhythmia like heart block.

Clinical Relevance

Nursing practice connection: Use the key finding related to Clinical manifestations of complete heart block (third-degree AV block) to guide bedside assessment, documentation, and the next nursing action.
Identifying syncope in a patient's history is a critical red flag that should prompt an immediate ECG to rule out life-threatening arrhythmias like complete heart block.
Complete heart block is a medical emergency because the slow ventricular rate can lead to cardiac arrest. The nurse must be prepared to initiate basic life support and assist with emergency cardiac pacing.
Patient safety is a top priority. A patient with suspected or confirmed complete heart block is at high risk for falls and injury due to unpredictable syncopal episodes.

How to Approach the Question

First, identify the core pathophysiology of the condition mentioned in the question: 'complete heart block'.
Recall that complete heart block means atrial impulses are completely blocked from reaching the ventricles.
Consider the hemodynamic consequence: the ventricles adopt a very slow 'escape' rhythm, leading to severe bradycardia and a significant drop in cardiac output.
Think about how a sudden drop in cardiac output affects major organs, especially the brain.
Evaluate the options based on this understanding. Syncope (fainting) is a direct result of inadequate blood flow to the brain (cerebral hypoperfusion).
Eliminate the other options: Tachycardia is the opposite of the expected heart rate, while headache and hemiparesis are not direct, primary symptoms of this cardiac condition.

Concept Tested & Keywords

Concept Tested: Clinical manifestations of complete heart block (third-degree AV block)
Stem keywords: clinical indicator, history and physical assessment, complete heart block
Lead-in keywords: most likely

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