Atropos

Atropos of Greek mythology was the eldest of the Three Fates, known as the "inflexible" or "inevitable." She determined the mechanism of death and ended the life of each mortal. Indeed, of the Fates, Clotho spun the thread of life, Lachesis measured the length of life, and Atropos ended it. Interestingly, Atropos lends her name to atropine, an anticholinergic medication which is used to speed up the heart. Indeed, we keep atropine in our crash carts for hemodynamic emergencies. But then, such a name might be fitting as atropine may indeed decide whether someone survives or dies.

Image of Bas relief of Atropos cutting the thread of life is shown under Creative Commons Attribution Share-Alike License, from Wikipedia.