During a surgery, Cristina experiences a severe post-traumatic breakdown on the operating room floor. This leads her to question her place in the hospital and eventually give her wedding ring back to Owen.
In this emotional aftermath of the hospital shooting, the doctors struggle to return to "normal." [S7E2] Shock to the System
Since the title can refer to a few different series, here are the dominant "stories" for each: "Grey's Anatomy" Shock to the System (TV Episode
In an episode also titled Barry Allen receives a literal and figurative "shock to the system": During a surgery
Barry gains the ability of "speed-thinking" thanks to the Artificial Speed Force, but it begins to strip away his humanity, making him cold and calculating.
"Grey's Anatomy" Shock to the System (TV Episode 2010) - IMDb
The medical case of the week involves a group of flag football players struck by lightning, forcing the doctors to work together under extreme pressure. The Flash (S7E2)