Stable Supraventricular Tachycardia Management
A 5-year-old girl presents with a 1-hour history of palpitations and mild dizziness. Her heart rate is 254 beats/min, blood pressure 98/60 mm Hg, oxygen saturation 99% in room air, and she is fully alert with warm extremities. A 12 lead electrocardiogram shows a regular narrow complex tachycardia with no discernible P waves. Intravenous access has been secured. Which of the following is the most appropriate first line intervention?
- A.Application of ice to the face
- B.Carotid sinus massage
- C.Valsalva maneuverCorrect
- D.Rapid intravenous adenosine
Explanation
In a hemodynamically stable child with supraventricular tachycardia, vagal maneuvers are the first line treatment because they increase atrioventricular nodal refractoriness and terminate reentry in a substantial proportion of cases without drugs. In a cooperative child older than about 1 year the Valsalva maneuver is preferred, performed by asking the child to blow through a straw or against a closed glottis, or by blowing on the thumb, and its efficacy improves if the child is then laid supine with the legs raised. In infants younger than 1 year who cannot cooperate, the diving reflex is elicited instead by applying a bag of iced water to the face for about 15 seconds. Carotid sinus massage and ocular pressure are not recommended in children because of the risk of retinal injury and cerebral hypoperfusion and because they are less effective. Adenosine given as a rapid push through a large bore proximal or central line with an immediate saline flush, at 0.1 mg/kg and then 0.2 mg/kg if needed, is the drug of choice but comes after vagal maneuvers fail in a stable patient. Second line agents include procainamide or amiodarone; verapamil must be avoided in infants under 1 year because of the risk of cardiovascular collapse and in patients with Wolff-Parkinson-White syndrome. Synchronized cardioversion at 0.5 to 1 J/kg is reserved for hemodynamic instability. Continuous electrocardiographic recording during any of these interventions helps confirm the mechanism of the arrhythmia.
Why each option
- A.
- Ice to the face elicits the diving reflex and is the preferred vagal maneuver for infants under 1 year, not a cooperative 5-year-old.
- B.
- Carotid sinus massage is not recommended in children because of limited efficacy and risk of cerebral hypoperfusion.
- C.
- Correct. The Valsalva maneuver is the first line vagal maneuver in a stable cooperative child with supraventricular tachycardia.
- D.
- Adenosine is highly effective but is used after vagal maneuvers fail in a hemodynamically stable child.
Reference: AHA Pediatric Advanced Life Support Guidelines, 2020
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