42 CFR § 415.190 - Conditions of payment: Assistants at surgery in teaching hospitals.
(a) Basis, purpose, and scope. This section describes the conditions under which Medicare pays on a fee schedule basis for the services of an assistant at surgery in a teaching hospital. This section is based on section 1842(b)(7)(D)(I) of the Act and applies only to hospitals with an approved GME residency program. Except as specified in paragraph (c) of this section, fee schedule payment is not available for assistants at surgery in hospitals with—
(1) A training program relating to the medical specialty required for the surgical procedure; and
(2) A resident in a training program relating to the specialty required for the surgery available to serve as an assistant at surgery.
(c) Conditions for payment for assistants at surgery. Payment on a fee schedule basis is made for the services of an assistant at surgery in a teaching hospital only if the services meet one of the following conditions:
(1) Are required as a result of exceptional medical circumstances.
(2) Are complex medical procedures performed by a team of physicians, each performing a discrete, unique function integral to the performance of a complex medical procedure that requires the special skills of more than one physician.
(3) Constitute concurrent medical care relating to a medical condition that requires the presence of, and active care by, a physician of another specialty during surgery.
(4) Are medically required and are furnished by a physician who is primarily engaged in the field of surgery, and the primary surgeon does not use interns and residents in the surgical procedures that the surgeon performs (including preoperative and postoperative care).
(5) Are not related to a surgical procedure for which CMS determines that assistants are used less than 5 percent of the time.