Nicotine misused outside hospital in a risky location

• Once hit in crash, vulnerable
• About to take the plunge perhaps, mixing nicotine with heroin
• Destroyed nicotine, protecting hearts at risk
• At risk, prior to a breakthrough?

Wikipedia Word definitions in Wikipedia
On Thin Ice is a 1933 British crime film directed by Bernard Vorhaus and starring Ursula Jeans , Kenneth Law and Dorothy Bartlam .

Wiktionary Word definitions in Wiktionary
a. (context idiomatic English) In a dangerous, hazardous, or delicate situation; at risk.