Anesthesia Coding Alert

Question: Would you explain the difference between MAC (monitored anesthesia care) and IV sedation? I know we use modifier QS with the anesthesia code for MAC. Should we report both types if our physician indicates IV sedation?

Massachusetts Subscriber

Answer: Modifier QS (Monitored anesthesia care service) only applies to anesthesia codes (not surgical codes) and does not cross to the moderate sedation codes.

CPT includes six moderate (conscious) sedation codes that differ according to the patient's age and the duration of service. The two primary MAC codes are:

• 99143 -- Moderate sedation services (other than those services described by codes 00100-01999) provided by the same physician performing the diagnostic or therapeutic service that the sedation supports, requiring the presence of an independent trained observer to assist in the monitoring of the patient's level of consciousness and physiological status ...

• 99148 -- Moderate sedation services (other than those services described by codes 00100-01999), provided by a physician other than the healthcare professional performing the diagnostic or therapeutic service that the sedation supports ...

Each code has subcodes based on the patient's age and the length of service.

Ground rules: If an anesthesiologist administers care for the case, he should indicate MAC and you should bill it that way (with the appropriate anesthesia code and modifier QS) instead of coding for moderate sedation.

If a physician from another specialty administers IV sedation, the moderate sedation codes apply; because of the notation regarding "services described by codes 00100-01999," you shouldn't report the moderate sedation codes for your anesthesiologist's services.