“So, how do you think the shift went?”  Gregor reflects for a moment and recalls having difficulty diagnosing a sick elderly patient with abdominal pain. “I think I’ll read about red flags in abdominal pain.” “That’s a great idea,” says Dr. Tran, “Why don’t you read about the sensitivity of serum lactate in acute mesenteric ischemia?” One of the valuable teaching moments in Emergency Medicine is at the end of the shift, where …