physician signature requirements

When a patient is seen by the nurse only for an injection or b/p check, is the physician required to sign off on the visit? This has really come up with EHR since the physician would have to physically access those visits to sign off.
Thanks

depends

Are you billing an E&M, like a nurse visit- 99211? If so, then the doc better document her medical decision making and authenticate her note. If just a venipuncture or BP check with no "thinking" then no need to be signed.

physician signature requirements

What about for an injection?