Tachycardia Flashcards
7 cards from real PALS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Tachycardia flashcards as text
A 6-year-old with SVT is being monitored; the team cannot obtain IV access. What alternative route can adenosine be given?
Answer: Intraosseous (IO)
Intraosseous (IO) access is an acceptable alternative to IV for adenosine administration when IV access cannot be established rapidly.
Which of the following best describes the mechanism of action of adenosine in terminating SVT?
Answer: Transiently blocks AV nodal conduction, interrupting re-entry circuits
Adenosine acts on A1 receptors to transiently block AV nodal conduction, which interrupts the re-entry circuit responsible for most SVT.
A 4-year-old with SVT converts to sinus rhythm after adenosine but then reverts to SVT 30 seconds later. What does this most likely indicate?
Answer: The dose was adequate but the underlying trigger needs treatment
Recurrence of SVT after successful adenosine conversion often indicates a persistent underlying trigger (e.g., fever, electrolyte abnormality) or an accessory pathway; the next dose should be doubled or an alternative agent considered.
What is the maximum single dose of adenosine in a pediatric patient?
Answer: 12 mg
The maximum single dose of adenosine in children is 12 mg, regardless of weight, to prevent excessive side effects.
Which sign most reliably indicates that a child with tachycardia has progressed to cardiovascular compromise requiring immediate intervention?
Answer: Altered mental status and poor perfusion despite tachycardia
Altered mental status combined with poor perfusion (weak pulses, mottling, prolonged cap refill) indicates end-organ compromise and mandates immediate treatment.
A 12-year-old athlete collapses on the field with a wide-complex tachycardia at 210 bpm and no pulse. What is the correct immediate intervention?
Answer: Unsynchronized defibrillation at 2 J/kg
Pulseless wide-complex tachycardia (VT without a pulse) is treated as VF: immediate unsynchronized defibrillation at 2 J/kg followed by CPR.
During resuscitation of a child with pulseless VT, after the first defibrillation attempt and 2 minutes of CPR, the rhythm check reveals ongoing VT without a pulse. What drug is given next?
Answer: Epinephrine 0.01 mg/kg IV/IO
For shockable rhythms (pulseless VT/VF), epinephrine 0.01 mg/kg IV/IO is given after the second shock and then every 3-5 minutes during CPR.