Modifier 73- Discontinued Outpatient Procedure Prior to Anesthesia Administration

Identifies a hospital outpatient or ambulatory surgical center procedure that is discontinued after the patient is prepared and taken to the procedure room but before anesthesia is administered.

What Is Modifier 73?

Modifier 73 identifies a discontinued outpatient hospital or ambulatory surgical center procedure before the administration of anesthesia.

CMS uses Modifier 73 when a procedure requiring anesthesia is terminated because of extenuating circumstances or circumstances threatening the patient's well-being after the patient has been prepared for the procedure and taken to the room where it would be performed, but before anesthesia is administered.

Modifier 73 is a facility reporting modifier. It applies to hospital outpatient departments and ASCs rather than the physician's professional claim.

For hospital outpatient billing, CMS defines anesthesia broadly to include local anesthesia, regional blocks, moderate sedation, deep sedation, and general anesthesia.

When to Use Modifier 73

Patient Is Prepared: The patient has been prepared for the scheduled procedure, including procedural premedication when provided.

Patient Reaches Procedure Room: The patient has been taken to the room where the procedure is scheduled to occur.

Anesthesia Is Planned: The procedure is one for which anesthesia is planned.

Anesthesia Has Not Started: The procedure is discontinued before anesthesia is administered.

Extenuating Circumstances: An unexpected circumstance prevents the procedure from continuing.

Patient Well-Being: A clinical circumstance threatening the patient's well-being requires cancellation of the procedure.

When NOT to Use Modifier 73

Before Procedure-Room Preparation: Do not use Modifier 73 when the procedure is cancelled before the patient has been prepared and taken to the procedure room.

After Anesthesia: Modifier 74 generally applies when a qualifying facility procedure is discontinued after anesthesia has been administered or after the procedure has begun.

Elective Cancellation: CMS states that an elective cancellation should not be reported as a discontinued procedure with Modifier 73.

Physician Professional Claim: Modifier 73 is intended for hospital outpatient and ASC facility reporting. Modifier 53 may apply to qualifying discontinued physician services.

No Anesthesia Planned: CMS uses Modifier 52 for qualifying reduced or discontinued hospital outpatient services for which anesthesia was not planned.

Billing Example

A patient is scheduled for an outpatient surgical procedure requiring anesthesia at an ASC.

The patient completes preoperative preparation and is taken into the procedure room. Before anesthesia is administered, the patient's condition changes and the physician determines that proceeding would threaten the patient's well-being.

The ASC reports the appropriate procedure code with Modifier 73.

The modifier allows the facility to identify the discontinued procedure and the resources already used preparing the patient and procedure room.

Documentation Requirements

Scheduled Procedure: Document the procedure that was intended to be performed.

Patient Preparation: Establish that the patient had been prepared for the procedure.

Procedure-Room Entry: Document that the patient had been taken to the room where the procedure was scheduled to occur.

Anesthesia Status: Clearly establish that anesthesia had not yet been administered.

Reason for Discontinuation: Document the clinical or extenuating circumstance requiring the procedure to be stopped.

Resources Used: Maintain documentation supporting the facility services and resources furnished before discontinuation.

Billing and Claim Considerations

Modifier 73 is specifically designed to recognize facility resources consumed before a procedure is discontinued.

Under Medicare OPPS rules, qualifying procedures discontinued after the patient has been prepared and taken to the procedure room but before anesthesia is administered are generally paid at 50% of the full OPPS payment amount.

CMS also applies Modifier 73 rules to ASCs. Specific payment calculations can vary based on the service and applicable ASC payment methodology, including special treatment for certain device-intensive procedures.

The timing of the discontinuation is therefore critical. The record must distinguish whether the procedure stopped before or after anesthesia administration.

Common Billing Mistakes

Confusing 73 With 74: Modifier 73 applies before anesthesia; Modifier 74 generally applies after anesthesia or after the procedure has begun.

Using 73 on Professional Claims: Modifier 73 is intended for HOPD and ASC facility reporting.

Reporting an Elective Cancellation: A voluntarily cancelled or postponed procedure does not automatically qualify.

Patient Never Reached Procedure Room: Modifier 73 requires that the patient has been prepared and taken to the room where the procedure would be performed.

Ignoring the Anesthesia Definition: For HOPD billing, anesthesia includes more than general anesthesia and encompasses local, regional, moderate, and deep sedation.

Using 73 When No Anesthesia Was Planned: Modifier 52 may be appropriate for qualifying reduced or discontinued services where anesthesia was not planned.

Common Denial Reasons

Timing Not Supported: Documentation does not establish that the procedure was discontinued before anesthesia.

Patient Preparation Not Documented: The record does not show that the patient had been prepared and taken to the procedure room.

Incorrect Modifier: Circumstances support Modifier 52, 53, or 74 instead.

Elective Cancellation: The documentation indicates the procedure was electively cancelled rather than discontinued because of qualifying circumstances.

Medical Necessity Not Supported: The underlying procedure or circumstances are insufficiently documented.

Facility Requirements Not Met: The claim does not satisfy applicable HOPD or ASC discontinued-procedure requirements.

Modifier 73 vs. Modifier 74

Modifier 73: Procedure discontinued after preparation and arrival in the procedure room but before anesthesia administration.

Modifier 74: Procedure discontinued after anesthesia administration or after the procedure has begun.

The critical distinction is when the procedure is discontinued relative to anesthesia and procedure initiation.

Modifier 73 vs. Modifier 53

Modifier 73: Used by hospital outpatient departments and ASCs for qualifying discontinued procedures before anesthesia.

Modifier 53: Used for qualifying discontinued physician or other professional services.

CMS specifically states that Modifier 53 is not approved for reporting discontinued hospital outpatient services.

Frequently Asked Questions

Can Modifier 73 be used if the patient never enters the procedure room?
No. Under Medicare rules, the patient must have been prepared for the procedure and taken to the room where it was scheduled to be performed before the qualifying discontinuation occurs.

Does Medicare reduce payment when Modifier 73 is reported?
Yes. Under OPPS, a qualifying procedure reported with Modifier 73 is generally paid at 50% of the full OPPS payment amount because the procedure was discontinued before anesthesia.