Trying to make sense of a code we had today.

I'm a scribe in an ED and today I saw the weirdest code. There was a lot of speculation about the possible causes behind the patient's presentation but since we're not going to get any answers, I figured I'd write about it here to see if anyone has any ideas or can help me make sense of it. I've changed the details of this case to protect anonymity.

A patient in his 40s with zero PMHx presented via EMS after a syncopal episode preceded by multiple episodes of vomiting at breakfast. Pt's mom states they'd just finished eating and he just doubled over, vomited for about 20 minutes, then passed out. When EMS got there he was A/Ox3, 12-lead showed sinus tach, O2 sat in the 80s. He presented super diaphoretic and about 2 minutes after arrival he syncopized again. EKG at this time showed sinus tach. Breath sounds were clear. Blood glucose 122.

At this point they became hypoxic, O2 sat 70s, and would go in and out of apnea even with vigorous sternal rubbing. When he would wake for brief periods of time he was very agitated, trying to remove his NRB and get out of bed. This lasted for about 5 minutes before the final LOC at which time he stopped breathing, was cyanotic, and HR dropped into the 30s. Then pulse check: none. Pupils were found to be dilated to 8 mm but equal and reactive. No hx of benzo/stimulant use. Pt was moved to a bigger room, bagged, compressions started.

8 rounds of epi, 2 rounds of bicarb, 4000 of heparin, and an epi drip later, the patient had regained ROSC 6 times only to lose it a minute later. At one point the monitor looked STEMI-ish so another EKG was done showing ST elevations in V3 and V4, but depressions in I, aVL, V5, and V6. He was coded for about 45 minutes total.

Talking to family, it seems they have a strong history of sudden cardiac arrest at a young age. But what's up with the EKG findings and the dilated pupils? This was a perfectly healthy person; no DM, no CAD, no HTN. It was just so weird how quickly everything went from a vasovagal-sounding syncope to a code. How does that happen?