Emil
Emil was a sophisticated Emergency Medical Hologram used during the late 24th century by  Cristóbal Rios aboard La Sirena. He was one of several emergency holograms (the others being Emmet, Enoch, Ian, and Mister Hospitality), and his appearance was based on that of Rios, though he had an English accent.

When Jean-Luc Picard beamed aboard La Sirena in 2399 to speak with Rios, he was greeted by Emil, who brought Picard to meet the wounded Rios. After Emil partially treated the wound, Rios deactivated him. ()

Weeks later, when Doctor Agnes Jurati was murdering Doctor Bruce Maddox, Emil activated automatically, but Jurati was able to deactivate it with a verbal command, enabling her to kill Maddox. ()

After Jurati injected herself with noranium hydride, Emil was once again activated, and alerted Captain Rios and Raffi Musiker to the fact that Jurati was in a coma. ()

When La Sirena arrived at Nepenthe, Emil explained to Picard and Musiker that Jurati turned off the hematic microrepair unit that was healing Maddox and then deactivated the hologram. ()

Appendices

Appearances

Background information
Emil was played by Santiago Cabrera.

Emil's name was not established on screen, but was revealed by Michael Chabon on his Instagram account. 
Holograms
Medical practitioners
Memory Alpha articles named from supplementary resources