PEDIATRIC TACHYCARDIA ALGORITHM (PALS GUIDELINES)
Tachycardia in pediatric patients can be a normal physiologic response (e.g., fever, dehydration) or a life-threatening arrhythmia (e.g., supraventricular tachycardia [SVT] or ventricular tachycardia [VT]). Early differentiation between stable and unstable tachycardia is critical for guiding treatment.
Key Goals of Tachycardia Management:
Differentiate between sinus tachycardia, SVT, and VT. Determine if the patient is stable or unstable. Provide appropriate treatment, including vagal maneuvers, medications, or cardioversion.
DIFFERENTIATING TYPES OF PEDIATRIC TACHYCARDIA
Tachycardia Type Rate Rhythm P Wave QRS Duration Key Features
Sinus Tachycardia <220 bpm (infants) <180 bpm (children) Regular Present Narrow Responds to fluids, rest, or fever control
Supraventricular Tachycardia (SVT) >220 bpm (infants), >180 bpm (children) Regular Absent or hidden Narrow Sudden onset, poor perfusion, no variability with movement
Ventricular Tachycardia (VT) Variable Regular Absent Wide (>0.09 sec) May have poor perfusion, risk of deterioration to VF/PEA
Key Differentiators:
- Sinus tachycardia has normal P waves, responds to fluid and fever control.
- SVT is very fast, regular, with no P waves and poor perfusion.
- VT has wide QRS complexes and is life-threatening.
PEDIATRIC TACHYCARDIA MANAGEMENT ALGORITHM
Step 1: Assess for Unstable vs. Stable Tachycardia
Signs of Unstable Tachycardia (Shock Symptoms):
- Altered mental status (lethargy, unresponsiveness).
- Hypotension (SBP < 5th percentile for age).
- Signs of poor perfusion (weak pulses, delayed capillary refill, mottled skin).
- Respiratory distress.
If unstable → Immediate synchronized cardioversion (Step 3). If stable → Further rhythm assessment (Step 2).
Step 2: Identify the Tachycardia Type
Sinus Tachycardia:
- Treat the underlying cause (fever, dehydration, pain).
- No cardioversion or antiarrhythmics needed.
Narrow Complex Tachycardia (SVT suspected, QRS <0.09 sec):
- Attempt vagal maneuvers (ice to the face, blowing into a syringe).
- If ineffective, administer Adenosine 0.1 mg/kg IV/IO (max 6 mg), repeat with 0.2 mg/kg if needed (max 12 mg).
Wide Complex Tachycardia (VT suspected, QRS >0.09 sec):
- If monomorphic (stable) → Consider amiodarone or procainamide.
- If unstable → Perform immediate synchronized cardioversion (0.5-1 J/kg).
Do NOT use adenosine for wide complex tachycardia—it may worsen VT.
Step 3: Management of Unstable Tachycardia (Synchronized Cardioversion)
Indications for Synchronized Cardioversion:
- Unstable SVT or VT (poor perfusion, hypotension, altered mental status).
- Persistent tachycardia with severe symptoms despite vagal maneuvers or medications.
Cardioversion Doses:
- First shock: 0.5-1 J/kg synchronized.
- Second shock (if ineffective): 2 J/kg synchronized.
For awake children, consider sedation before cardioversion if time allows.
Step 4: Medications for Tachycardia
Narrow Complex Tachycardia (SVT): Adenosine (first-line for SVT)
- 0.1 mg/kg IV rapid push (max 6 mg) → If ineffective, 0.2 mg/kg (max 12 mg).
- Follow with immediate saline flush. Beta-blockers (if adenosine fails, expert consultation needed).
Wide Complex Tachycardia (VT): Amiodarone: 5 mg/kg IV over 20-60 minutes (max 300 mg). Procainamide (alternative to amiodarone): 15 mg/kg IV over 30-60 minutes.
Avoid using amiodarone and procainamide together due to risk of QT prolongation and arrhythmias.
QUICK REFERENCE: PEDIATRIC TACHYCARDIA MANAGEMENT
| Step | Action | Key Considerations |
|---|---|---|
| 1 | Assess Stability | Unstable? → Immediate synchronized cardioversion |
| 2 | Identify Rhythm | Sinus tachycardia, SVT, or VT? |
| 3 | Vagal Maneuvers (if stable SVT) | Ice to face, Valsalva maneuver |
| 4 | Adenosine (if SVT persists) | 0.1 mg/kg IV push, repeat 0.2 mg/kg if needed |
| 5 | Cardioversion for Unstable Tachycardia | 0.5-1 J/kg → increase to 2 J/kg |
| 6 | Amiodarone/Procainamide for VT | 5 mg/kg IV over 20-60 min (Amiodarone) |
WHEN TO ESCALATE BEYOND STANDARD TREATMENT?
If SVT is refractory to adenosine:
- Consider beta-blockers (propranolol, esmolol) or synchronized cardioversion.
If VT is refractory to medications or cardioversion:
- Consider expert consultation and transvenous pacing.
- Evaluate for electrolyte imbalances, myocarditis, or structural heart disease.
If WPW Syndrome (Wolff-Parkinson-White) is suspected:
- Avoid adenosine, digoxin, and calcium channel blockers.
- Use procainamide or amiodarone cautiously.
SIGNS OF IMPROVEMENT AFTER TREATMENT
Heart rate normalizes for age. Strong pulses, normal capillary refill (<2 sec). Improved mental status (alert, responsive). Stable blood pressure and perfusion.
If these signs are absent, continue resuscitation and escalate treatment.
SUMMARY: WHY TIMELY INTERVENTION IN PEDIATRIC TACHYCARDIA MATTERS
Distinguish sinus tachycardia from life-threatening arrhythmias. SVT responds well to vagal maneuvers and adenosine. VT requires urgent management—synchronized cardioversion if unstable. Identify and correct underlying causes (fever, dehydration, myocarditis, WPW).
Takeaway: Prompt recognition and intervention in pediatric tachycardia can prevent deterioration into cardiac arrest and improve outcomes.