STABLE Cardiac Part I

Summary

In this video, Austin Kaiser, a clinical educator, guides viewers through the physical assessment of newborns with congenital heart defects (CHD). Covering vital signs, skin changes, pulses, liver size, and neurological status, he highlights key red flags like tachypnea, bradycardia, cyanosis, and hepatomegaly. The session also explores common genetic syndromes associated with CHD, including Down, Edwards, Patau, Turner, VACTERL, CHARGE, and DiGeorge syndromes. Precordial assessment, heart sounds, and murmurs are discussed, emphasizing early recognition and differentiation of abnormal findings. This practical module equips clinicians with essential knowledge to identify, assess, and respond to CHD in neonates effectively.

Takeaways

• 😀 Newborn respiratory rate should be 30–60 breaths per minute; sustained tachypnea with a comfortable baby may indicate early congenital heart defect.
• 😀 Bradycardia (<30 bpm) or gasping are ominous signs requiring immediate intervention; sustained bradycardia may indicate serious pathology or third-degree heart block.
• 😀 Normal neonatal heart rate ranges from 120–160 bpm, with SVT defined as >220 bpm.
• 😀 Blood pressure assessment is important, but hypotension is a late sign of decompensation; significant arm-leg differences may indicate coarctation or interrupted aortic arch.
• 😀 Skin assessment: central cyanosis, delayed capillary refill (>3 seconds), mottling, or cool extremities indicate potential cardiac or perfusion issues.
• 😀 Pulse assessment: brachial and femoral pulses should be equal and easily palpable; differences or bounding pulses may indicate outflow obstruction or wide pulse pressure from PDA or AV malformation.
• 😀 Liver assessment: should be just palpable below the right costal margin; hepatomegaly suggests congestive heart failure; rare left-sided liver may be associated with situs inversus or dextrocardia.
• 😀 Neurological and feeding assessments are critical; weak sucking, weak cry, poor tone, or flaccidity indicate poor neurological function.
• 😀 Gestational age and chromosomal abnormalities are important for CHD risk assessment; Down syndrome, Edwards syndrome, Patau syndrome, Turner syndrome, CHARGE, and deletion syndromes all have associated heart defects.
• 😀 Precordial assessment: PMI typically at 5th intercostal space, left lower sternal border; hyperactive or shifted PMI may indicate dextrocardia, tension pneumothorax, or diaphragmatic hernia.
• 😀 Heart sounds and murmurs: S1 is closure of mitral/tricuspid valves, S2 is closure of aortic/pulmonic valves; abnormal murmurs indicate stenosis, regurgitation, or septal defects, with timing relative to S1/S2 helping identify the affected valve.

Q & A

What is considered a normal respiratory rate for a newborn?

A normal respiratory rate for a newborn is 30 to 60 breaths per minute with effortless breathing.

What does sustained tachypnea in a newborn without distress indicate?

Sustained tachypnea in a newborn who appears comfortable may be an early sign of a congenital heart defect (CHD).

At what heart rate is bradycardia considered abnormal in a newborn?

Sustained bradycardia below 120 beats per minute is abnormal and may indicate acidosis, hypotension, hypoxemia, or infection.

How can you differentiate sinus bradycardia from a pathological third-degree heart block?

Sinus bradycardia is often reversible and can result from vagal stimulation or procedures like intubation. Third-degree heart block is pathological, typically associated with maternal lupus, with ventricular rates of 45–80 bpm in newborns.

What is the significance of differences in blood pressure between a newborn's arms and legs?

Significant differences, such as higher blood pressure in the arms than legs, may indicate obstruction to blood flow, like coarctation of the aorta or interrupted aortic arch.

Which skin findings suggest central cyanosis in a newborn?

Central cyanosis is indicated by bluish discoloration of mucous membranes, tongue, and nail beds, suggesting arterial desaturation due to cardiac or pulmonary dysfunction.

What pulse abnormalities should raise concern for congenital heart defects?

Weak or absent brachial or femoral pulses suggest reduced cardiac output or outflow obstruction. Bounding pulses may indicate a widened pulse pressure from a large PDA or AV malformation.

Which chromosomal conditions are commonly associated with congenital heart defects?

Trisomy 21 (Down), Trisomy 18 (Edwards), Trisomy 13 (Patau), Turner syndrome, VACTERL, CHARGE, and DiGeorge syndromes have high incidences of congenital heart defects.

How is precordial activity assessed, and what abnormalities might it reveal?

Precordial activity is assessed by palpating the chest for the point of maximal impulse (PMI), normally at the 5th intercostal space, lower left sternal border. Abnormal PMI (hyperactive, shifted) can indicate dextrocardia, tension pneumothorax, or diaphragmatic hernia.

What do S1 and S2 heart sounds represent, and how are murmurs identified in newborns?

S1 is the closure of mitral and tricuspid valves (start of systole), and S2 is the closure of aortic and pulmonic valves (start of diastole). Murmurs are abnormal flow sounds occurring between these valves, often indicating stenosis, regurgitation, or septal defects.

Why is liver size important in neonatal cardiac assessment?

The liver should be palpable just below the right costal margin (<3 cm). Hepatomegaly indicates congestive heart failure or systemic venous congestion.

What neurological signs suggest compromised neonatal function?

Poor sucking reflex, weak cry, irritability, flaccidity, or abnormal tone may indicate neurological compromise and warrant further evaluation.