A 60yo pt recovering from a surgery for toxic goiter is found to be hypotensive, cyanosed in the the RR. Exam: tense neck. There is blood oozing from the drain. What is the most likely dx?

The key is B. Reactionary haemorrhage. [in the recovery room, cyanosis, hypotension, tense neck, woozing of blood from drain, all these goes in favour of reactionary haemorrhage. "reactionary," hemorrhage that occurs within the first 24 hours after surgery].