A nurse is performing a physical assessment of a pediatric client. While auscultating the heart, the nurse hears physiological splitting of S2 when the child takes a deep breath. Which action should be taken by the nurse?

Physiological splitting of S2 occurs when the aortic (A2) and pulmonic (P2) components of the second heart sound are heard as two distinct sounds during inspiration. This is a normal finding in healthy children and adults, caused by increased venous return during inspiration, which delays closure of the pulmonic valve.

Rationale for correct answer:

D. Document the findings as a normal finding: Physiological splitting is most prominent during deep inspiration and is considered normal, especially in children, adolescents, and young adults. No intervention or provider notification is required unless other abnormal findings are present such as cyanosis, murmurs, or signs of heart failure. Accurate documentation ensures continuity of care and reflects the child’s normal cardiac physiology.

Rationale for incorrect answers:

A. Notify the provider of suspected atrial-septal defect (ASD): ASD can cause fixed splitting of S2, which is present in both inspiration and expiration. Physiological splitting is variable with respiration and does not indicate a septal defect.

B. Notify the provider of suspected pulmonary stenosis: Pulmonary stenosis may produce a loud systolic ejection murmur with fixed splitting, not normal physiological splitting. The described finding does not suggest pathology.

C. Follow institutional policy for initiating an emergency response: This is unnecessary because physiological splitting of S2 is a normal, nonemergent finding.

Test-taking strategy:

• Distinguish physiological vs. pathological splitting:
  • Physiological splitting: occurs only with inspiration, varies with respiration, normal in children.
  • Pathological splitting: fixed or paradoxical, may indicate ASD, bundle branch block, or pulmonary stenosis.
• If the split changes with breathing and no other abnormalities are present, it is normal.

Take home points

• Physiological splitting of S2 is a normal variation in children and adults during deep inspiration.
• Documenting normal findings is appropriate; no emergency or provider notification is required.
• Fixed or paradoxical splitting, loud murmurs, or other abnormal signs should prompt further evaluation.
• Understanding normal cardiac sounds prevents unnecessary interventions and anxiety.

Cardiac assessment is a systematic evaluation of the heart and circulation that combines history-taking, physical examination, and diagnostic techniques to identify cardiovascular health, risks, or disease. It focuses on vital signs, inspection, palpation, auscultation, and sometimes point-of-care imaging to detect abnormalities in heart function and blood flow.

Rationale for correct answer:

D. Fifth intercostal space, left midclavicular line: The first heart sound (S1) is produced by the closure of the atrioventricular (AV) valves, the mitral and tricuspid valves, at the beginning of ventricular systole. S1 is loudest at the apical area. In clinical testing, the apex is classically identified as the 5th intercostal space at the left midclavicular line, which is considered the standard landmark for auscultating SA. The diaphragm of the stethoscope is preferred because S1 is a high-pitched sound.

Rationale for incorrect answers:

A. Third or fourth intercostal space: These locations are closer to the base of the heart, where S2, the closure of aortic and pulmonic valves is louder than SA.

B. The apex with the stethoscope bell: Using the bell is better for low-pitched sounds, like S3 or S4, not the high-pitched SA.

C. Second intercostal space, midclavicular line: The second intercostal space corresponds to the aortic and pulmonic areas, where S2 is best heard, not SA.

Test-taking strategy:

• For heart sounds, exams often prefer precise anatomical landmarks over general descriptions.
• Remember S1 is caused by AV valve closure (mitral/tricuspid) best heard at the apex of the heart.
• Remember S2 is caused by semilunar valve closure (aortic/pulmonic).
• Use the diaphragm for high-pitched sounds (S1, S2), and bell for low-pitched sounds (S3, S4, murmurs).

Take home points

• S1 results from mitral and tricuspid valve closure and is best at apex (5th ICS, left midclavicular line).
• S2 is caused by aortic and pulmonic valve closure and is best at base (2nd ICS, right and left).
• Correct auscultation location is essential for identifying murmurs, rhythm abnormalities, and cardiac function in children.