What does modifier 23 refer to?

Modifier 23 is used to indicate that an unusual anesthesia service was provided during a surgical procedure. This modifier is appended to the anesthesia code when the anesthesia administered is significantly greater than what would normally be expected for the procedure performed. It alerts payers that there were atypical conditions influencing the anesthesia management, which may include patient comorbidities, unexpected complications, or an intricate surgical environment.

Using this modifier helps ensure proper coding and reimbursement for anesthesia services that deviated from standard expectations, providing a clearer understanding of the medical necessity for the increased resources and attention required during that particular service.