A brain surgery can result in worse still: like, surgeon performs a surgery, makes some mistake, the patient is alive and gets up and goes home, but due to the surgical damage caused becomes a serial killer.
So, strictly speaking a brain surgery can also result in a body count that is greater than 1.
On a similar note, there's also the case of the leg amputation that killed 3 people: the patient (gangrene), the assistant (gangrene from fingers accidentally being amputated) and a spectator (from "fright").
A brain surgery can result in worse still: like, surgeon performs a surgery, makes some mistake, the patient is alive and gets up and goes home, but due to the surgical damage caused becomes a serial killer.
So, strictly speaking a brain surgery can also result in a body count that is greater than 1.
Respectfully submitted.