EKG Challenge No. 6 - Troubling Teenagers

You are working the day shift at Children's Hospital when you get a medical control call from EMS.  They responded to a call for "altered behavior" at a house to find a partially-clothed and confused teenage boy who was discovered "talking nonsense" by his parents in the living room in the morning.  They call you because the patient is somewhat "agitated" and just won't stop picking at every line and piece of equipment.  They want your okay to give him some versed to chill him out.  You agree to 2 mg of IV versed and await his arrival in the emergency department.

On arrival, the patient has a dry mouth, dilated pupils, and speaks some unclear, but seemingly pleasant gibberish.  Mom, through her tears, tells you the patient takes no medications but has "experimented with drugs" in the past.  There is radio silence when you listen for bowel sounds and your ungloved hand meets a dry axilla.  Noting his heart rate in the 140's, you decide that it is prudent to get an EKG:

What is your differential diagnosis?  What would you do next?

Leave your thoughts.  Case Conclusion to be posted this Friday December 19.

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