Modifier 24 is used to indicate that an Evaluation and Management service was provided by the surgeon to a patient within the global period of a major or minor surgery.   The claim must be accompanied by documentation that supports that the service is not related to the postoperative care for the procedure. That is, the surgeon must also be treating another medical condition unrelated to the surgery.

Examples of supporting documentation include ICD-9-CM codes that are clearly unrelated to the surgery or documentation explaining the reason the visit was unrelated to surgery. 

Preoperative and postoperative critical care may be paid in addition to the global fee using modifier -24 if the patient is critically ill or injured and the critical care is unrelated to the specific anatomic injury or general surgical procedure performed.

If the surgeon is admitting a patient to a nursing facility for a condition unrelated to the surgery, the modifier -24 is used with the initial nursing facility care code and clear documentation that the admission was for a different diagnosis or condition than the surgery.