I work on day shift, and labs are drawn early morning so that when our doctors round, they are able to see them. I never call the doctor prior to rounds (unless very serious obviously!!) because they will be up on the unit (always prior to 8am).
I call for the following reasons *if ordered after rounds or results after rounds completed*
-results from a lab (only if abnormal)
-results from a study (ct, X-ray, etc)
-requesting a medication or care (inserting/removing foley, for example)
-change in patient status (increase in BP, LOC, etc)
-if family or pt is asking questions I can't answer and requesting I ask a doctor
-if my task list says notify Md
It's really on a patient to patient basis though..