PALS Tachycardia 2

Question 1

A 4-year-old presents with a heart rate of 200 bpm, narrow QRS complexes, and no P waves visible. The child is alert and playing. What is the most likely rhythm?

Accepted Answer

Supraventricular tachycardia (SVT)

Answer

SVT typically presents with abrupt-onset rates >180-220 bpm, narrow QRS, absent or retrograde P waves, and the child may still be alert if compensated.

Question 2

Which vagal maneuver is most appropriate as a first-line intervention for a stable child with SVT?

Accepted Answer

Valsalva maneuver

Answer

The Valsalva maneuver (bearing down or blowing through an occluded straw) is safe and commonly used in older children with stable SVT.

Question 3

A 7-year-old with SVT fails two doses of adenosine. The child remains stable with a HR of 220 bpm. What is the next recommended intervention?

Accepted Answer

Amiodarone 5 mg/kg IV

Answer

After adenosine failure in stable SVT, amiodarone 5 mg/kg IV over 20-60 minutes is a recommended second-line agent in PALS.

Question 4

What is the key ECG feature that distinguishes sinus tachycardia from SVT in an infant?

Accepted Answer

Presence of upright P waves before each QRS in leads I and aVF

Answer

In sinus tachycardia, normal upright P waves precede each QRS in leads I and aVF, whereas SVT typically lacks visible or has abnormal P waves.

Question 5

A 2-year-old is brought in with a heart rate of 280 bpm, poor perfusion, and altered mental status. What is the immediate treatment?

Accepted Answer

Synchronized cardioversion starting at 0.5-1 J/kg

Answer

Unstable SVT with hemodynamic compromise requires immediate synchronized cardioversion at 0.5-1 J/kg, escalating to 2 J/kg if needed.

PALS - Pediatric Advanced Life Support Practice Test

PALS - Pediatric Advanced Life Support Practice Test

PALS Tachycardia 2