What modifier is used when an anesthesiologist is medically directing one CRNA?

The appropriate modifier to use when an anesthesiologist is medically directing one Certified Registered Nurse Anesthetist (CRNA) is QY. This modifier indicates that the anesthesiologist is supervising a single CRNA during the procedure. The QY modifier distinguishes the level of supervision and is specific to the arrangement where an anesthesiologist oversees just one CRNA, allowing for precise billing and documentation within the guidelines set by the American Medical Association (AMA) and the Centers for Medicare & Medicaid Services (CMS).

The QZ modifier, on the other hand, is used to indicate that the CRNA is working independently and not under the supervision of an anesthesiologist. QK is utilized when an anesthesiologist is directing two, three, or four CRNAs simultaneously. QH is meant for the supervision of five or more CRNAs. Therefore, QY clearly reflects the scenario of a one-to-one medical direction between the anesthesiologist and the CRNA, making it the correct choice for this coding situation.