A nurse enters the room of a client and notices supraventricular tachycardia (SVT) on the telemetry monitor. After assessing the client, it is determined the client is unstable and symptomatic with a blood pressure of 60/40, altered level of consciousness, and a heart rate of 245 bpm. Which of the following should the nurse do first?

• Administer a beta blocker
• Continue to monitor
• Administer atropine
• Prepare for synchronized cardioversion