When a patient presents with narrow complex tachycardia and altered level of consciousness, what is the next step?

In cases of narrow complex tachycardia combined with an altered level of consciousness, it is crucial to address the potential for hemodynamic instability. Synchronized cardioversion is indicated when a patient exhibits signs of significant compromise, such as altered mental status, as it allows for immediate restoration of a normal rhythm. This therapeutic approach can stabilize the patient's condition rapidly, particularly if the tachycardia is contributing to decreased cardiac output and inadequate perfusion of vital organs.

The sedation prior to cardioversion is also essential to minimize discomfort and anxiety, ensuring the procedure can be conducted safely and effectively. This is especially important when the patient is already compromised, as the procedure can cause additional stress.

Other options would not be appropriate given the clinical scenario. Administering antiarrhythmic medication might delay treatment effectiveness, given the patient's altered level of consciousness and the urgency of stabilizing their condition. Monitoring the patient without intervention can risk further deterioration, and while emergency intubation may be considered in severely compromised patients, directly addressing the tachyarrhythmia with synchronized cardioversion is a more immediate and effective response in this situation.