Anesthesia Coding Alert

Good documentation is especially key.

The anesthesia section of CPT^® includes four add-on codes that represent special circumstances that can affect how the anesthesiologist or CRNA provides service. Some, such as +99100 (Anesthesia for patient of extreme age, younger than 1 year and older than 70 [List separately in addition to code for primary anesthesia procedure]) are easily understood because the descriptor specifically outlines the parameters for usage. Others are a bit more open to interpretation or can be confusing for coders to fully understand. If that's the case for your office and +99135 (Anesthesia complicated by utilization of controlled hypotension [List separately in addition to code for primary anesthesia procedure]), read on for some tips on real-world usage.

Tip 1: Fully Document the Circumstances

When deciding whether reporting +99135 is appropriate, remember that the circumstances qualifying for this are unique to anesthesia coding and identify certain patient conditions, operative conditions, or other special risk factors that lead the surgeon to believe the patient needs to be in a hypotensive state during surgery.

The following phrases should be present in the record to support the use of +99135:

• Hypotensive state induced
• Surgeon's request for hypotension initiated
• Blood pressure reduced to ____ per surgeon request.

"There isn't a hard and fast rule to what the blood pressure is reduced to for it to be considered induced hypotension," says Kelly Dennis, MBA, ACS-AN, CAN-PC, CHCA, CPC, CPC-I,  owner of Perfect Office Solutions in Leesburg, Fl. "It can be 20 to 30 percent lower than the normal blood pressure, but can depend on what the patient's blood pressure normally is."

Important: Do not rely on the patient's charted blood pressure alone when assigning +99135. Code +99135 is intended to be used only when hypotension is induced deliberately, not when it occurs as an incidental condition.

Tip 2: Mention the Surgeon

When a chart mentions controlled hypotension, the anesthesiologist closely monitored the patient's blood pressure while it dropped drastically and then leveled off. The low blood pressure allows the surgeon to work in a virtually bloodless field. Anesthesiologists often administer controlled hypotension during certain procedures (such as shoulder or hip surgery) at the surgeon's request.

If that's the situation for the claim you're filing, the anesthesiologist should document in the anesthesia record that the hypotension was at the surgeon's request.

Be aware:  Some payers won't increase the anesthesiologist's reimbursement because of hypotension unless you specify it up front. Also remember that primary code(s) that can be billed with add-on codes is at an insurer's discretion. Consider negotiating for a higher dollar amount in your contracts and include documentation of the agreement with your claim.

Tip 3: Remember the Rules of Qualifying Circumstances Codes

Because +99135 is an add-on code, you must report it in conjunction with a primary procedure code. Acceptable primary codes that can be billed with +99135 (or any other add-on code) are at the payer's discretion.

The Medicare Physician Fee Schedule assigns a status indicator of "B" (bundled code) to qualifying circumstances codes +99100 – +99140, which means they are not eligible for separate reimbursement under traditional Medicare guidelines. Other insurers, however, sometimes allow additional payment for qualifying circumstances if the services are deemed reasonable and necessary. The value of the additional codes is significant (up to 5 base units for +99116 and +99135), which can mean higher payment for the anesthesiologist or CRNA.

Even if the payer you're filing the claim to doesn't reimburse for the additional units of qualifying circumstances codes, reporting them helps paint a complete picture of the case and your anesthesia provider's work.

Extra tip: Make sure you don't report +99135 separately when the anesthesia code you're reporting already includes the service of +99135 (such as 00561, Anesthesia for procedures on heart, pericardial sac, and great vessels of chest; with pump oxygenator, younger than 1 year of age).