Sick as Sh*t
"Sick as sh*t" is the official medical term to describe a complicated patient with several active issues. It is a term that can only be learned through years and years of medical education and training.
Example of Dialogue
ATTENDING: So what can you tell me about the patient?
RESIDENT: He's sick as sh*t.
ATTENDING: Bravo! You're an incredibly sharp resident! Your med school taught you well. You're gonna be chief some day, well done!