Rapid overview: Emergency management of supraventricular tachycardia in children

Provide oxygen and ventilation immediately as needed.

• Potential causes of sinus tachycardia (dehydration, fever, pain, drugs).
• Signs of poor perfusion (poor capillary refill, hypotension, pallor, diminished mental status).
• Signs of heart failure (increased work of breathing, rales, hepatomegaly).

• The following are consistent with SVT:
  • Rate – Infants 220 to 280 bpm; children and adolescents 180 to 240 bpm.
  • Relentlessly regular rhythm without variation with respiration or activity.
  • Abnormal P waves (absent or negative in II, III, and aVF).
  • For wide QRS complex, assume the origin is ventricular (although in children, most are SVT with aberrant conduction)^¶.

• Children with SVT who are stable are unlikely to deteriorate suddenly.
• Begin treatment with vagal maneuvers and/or adenosine and consult pediatric cardiology.

• For unstable patients (depressed consciousness, poor perfusion, hypotension, or other signs of shock or severe heart failure), begin treatment to convert to sinus rhythm immediately.
• Continue oxygen and ventilation as needed.

• Vagal maneuvers – For infants, apply bag containing ice water to the face above the nose and mouth for 15 to 30 seconds. Do not obstruct ventilation. In older children, bearing down or blowing into an occluded straw for 15 to 20 seconds provides vagal stimulation. Do not use carotid massage or orbital pressure.

• Vagal maneuvers – Do not delay treatment to administer vagal maneuvers in unstable patients. Attempt while preparing for cardioversion or drug therapy.

• Adenosine – With continuous ECG monitoring, administer rapidly through IV closest to the central circulation. Initial dose: 0.1 mg/kg (maximum 6 mg); if no response in 2 minutes, repeat dose 0.2 mg/kg (maximum 12 mg). Follow each dose immediately with a saline flush of 5 mL^Δ.

• Without IV/IO in place:
  • Synchronized cardioversion – Cardiovert immediately all unstable patients without IV access. Use 0.5 to 1 J/kg. If not effective, increase to 2 J/kg.

• With IV/IO in place^◊:
  • Adenosine – If immediately available, adenosine may be given to unstable patients with narrow complex SVT with IV access while preparing to cardiovert. Initial dose is 0.1 mg/kg (maximum 6 mg); if no response in 2 minutes, repeat dose 0.2 mg/kg (maximum 12 mg). Follow each dose immediately with a saline flush of 5 mL^Δ.
  • Synchronized cardioversion – If adenosine is not immediately available or if there is no response to adenosine, synchronized cardioversion should be performed in all unstable patients with IV access. Use 0.5 to 1 J/kg. If not effective, increase to 2 J/kg.
  • IV antiarrhythmic options for refractory SVT – Alternative second-line agents that have been used in this setting include IV amiodarone, IV esmolol, IV procainamide, IV sotalol, and IV verapamil (in patients ≥1 year old). Choice of a second-line agent should be guided by expert consultation, given potential proarrhythmic and life-threatening hemodynamic collapse when administering multiple antiarrhythmic agents.^§