What vagal maneuver should a patient attempt for Narrow Complex Tachycardia?

The recommended vagal maneuver for a patient experiencing Narrow Complex Tachycardia involves blowing out of a 10 mL syringe for 5-10 seconds. This technique can help stimulate the vagus nerve, which plays a crucial role in regulating heart rate and can help to slow down or interrupt tachycardic rhythms.

When the patient blows out against the pressure of the syringe, it creates a transient increase in intrathoracic pressure. This hormonal response can lead to increased vagal tone through the baroreceptor reflex, thereby helping to restore a normal rhythm or rate in the heart.

Other maneuvers, such as holding one’s breath for an extended period, sneezing forcefully, or drinking a glass of water upside down, may not effectively stimulate the vagus nerve to the same extent or carry the same physiological response as blowing out against resistance. Therefore, while they may have some anecdotal efficacy in certain contexts, they are not the recommended method for managing Narrow Complex Tachycardia as effectively as the syringe technique.