When being treated you sometimes see women clothes opened at the top - bra seen no full nudity of breasts shown

Toward the end of season 1, lovemaking scenes are seen

Blood and injury detail in every episode as it's in a exceedingly busy emergency department which operated beyond capacity most/all of the year

The whole series is based in a hospital emergency department - so there is many potentially frightening or intense scenes in every episode

A particularly intense/scary storyline, involving the main characters, is added toward the end of season 1.