Green’s Dictionary of Slang

hospital n.

SE in slang uses

In compounds

hospital heroin (n.) [a synthetic opiate used in hospitals as a substitute for heroin]

(drugs) Dilaudid.

[US]Abel Dict. Drug Abuse Terms.
[US]ONDCP Street Terms 12: Hospital heroin — Dilaudid.
[UK]Guardian G2 20 Oct. 5: He had for years been addicted to prescription painkillers, aka ‘hospital heroin’.

In phrases

do you like hospital food? [the potential assailant asks this of a victim, who prob. replies ‘No’ and is told ‘Well you’d better get used to it’]

a threatening phr. used immediately before administering a beating; ad hoc vars. abound.

[UK]M. Amis London Fields 5: It took Keith several crunchy beatings, and the first signs of a liking for hospital food, before he concluded he wasn’t cut out for racketeering.
[UK]M. Newall ‘Sir Gawayne and the Grene Knight’ in Indep. Weekend Rev. 26 Dec. 1: And thenne Sir Gavin said: ‘You fond of hospital foode?’.