I agree with others that I have experienced the physician asking for "permission" to end resuscitation efforts. Nearly all hospital resusitive efforts are by a code "team", either specific teams or groups of professionals who have experienced multiple codes. The physicians are asking for other suggestions or comments before directing the team to cease efforts. It is frequently an emotional time for staff, and it allows us to "let go" as well. This is especially true in younger victims, trauma, or self-inflicted injuries resulting in death.
The basics apply first in any area of nursing practice: Physical Assessment Skills, Basic electolytes norms and treatments, basic hemodynamics and interventions, work up to Acid-Base balance and the physiology behind it, and then 12-lead. Always ask questions, depend on your experienced workers who have the heart of a teacher.