Final answer:
For monitored anesthesia care services, the modifier QS is used to denote MAC. If the surgery was complex and the patient had severe cardiopulmonary disease, the modifier G8 might be relevant, while G9 indicates deep sedation risk. In this specific case, QS would be the appropriate modifier.
Step-by-step explanation:
The modifiers used for monitored anesthesia care (MAC) services in a Medicare patient are specifically designed to convey the complexity and nature of the anesthesia service provided. Modifier QS is used to indicate monitored anesthesia care services. However, in the context of severe cardiopulmonary disease, another modifier that may be relevant is modifier G8, indicating that the surgery was complex or lengthy, requiring the anesthesia professional's full attention. Modifier G9 typically indicates that the patient is a deep sedation risk. It's important to note that while both QS and G9 could theoretically be used, QS is primarily used for billing purposes to indicate MAC was provided.
For this specific scenario, since the question does not mention risk factors related to deep sedation, but highlights the patient's history of severe cardiopulmonary disease, the use of modifier QS by itself would be appropriate for reporting monitored anesthesia care. However, the ultimate choice of modifier will depend on the specific circumstances of the surgery and the requirements of the payer.