Arranging your fridge
Talking to dying patients
Organ freezing
Penicillin
http://www.dailymail.co.uk/health/article-4272016/How-penicillin-saved-human-life-destroying-it.html
Paediatric surgery
http://www.dailymail.co.uk/health/article-4272004/Baby-world-s-youngest-survive-stomach-surgery.html
Early roller-coasters