Anesthesia Coding Alert

Carriers might allow extra units that boost bottom lines

A chart crosses your desk that includes field avoidance" in the case notes. You code the procedure and move on, but did you miss out on potential reimbursement by not paying attention to the field avoidance? Many coders say yes, depending on the procedure and the physician's documentation.

Understand What's Happening

 Before a coder knows that a notation about field avoidance might merit extra units, she must know what the term "field avoidance" actually means.

"Basically, field avoidance is when the anesthesiologist does not have direct access to the patient's face (or airway)," says Karen Glancy, CCS-P, director of coding with Anesthesia Management Partners in Chicago. "That makes it a higher-risk case, so the anesthesiologist gets to charge a little more."

The surgeon's preference and the procedure being performed dictate whether field avoidance comes into play.

Possibility 1: Procedure Dictates Field Avoidance

Certain procedures are virtually always done the same way, so the anesthesiologist or CRNA knows beforehand that the case will probably involve field avoidance. Cases falling into this category involve the surgeon and anesthesiologist sharing the patient's airway, including:
 

intracranial surgery
 

oral surgery
 

some dental surgery.

As Glancy notes, procedures involving the patient's head, neck or shoulder girdle are good candidates for field avoidance.
 
But don't automatically assume that field avoidance comes into play anytime you code a particular procedure, says Leslie S. Johnson, CCS-P, CPC, an anesthesia coder with Medical Income Concepts Inc., in Houston. "I see many procedures performed bythe same surgeon where some involve field avoidance and others don't," she says. "The surgeon uses a different technique for whatever reason that means field avoidance is not a factor."

Possibility 2: Patient's Position Meets Field Avoidance Criteria

At other times, field avoidance applies when the surgeon needs to have the patient in a certain position for the procedure. The main consideration from your coding perspective is that the patient's position could cause the anesthesiologist to have difficulty accessing the patient's airway if problems arise during surgery - and that could mean extra units for field avoidance.

"The majority of field avoidance cases I see are based on the patient's position," Glancy says.

She and Johnson share some examples of several procedures that could involve field avoidance because of the patient's position:
 

The patient might be in the prone position (lying face down) during a repair of his ankle tendon (27658, Repair, flexor tendon, leg; primary, without graft, each tendon). This crosses to anesthesia code 01470 (Anesthesia for procedures on nerves, muscles, tendons and fascia of lower leg, ankle and foot; not otherwise specified), which has 3 base units. The anesthesiologist can raise the procedure's base from 3 to 5 units for field avoidance because of the patient's position.
 

The surgeon excises a sebaceous cyst on the back of the patient's thigh. The anesthesia code is 00400 (Anesthesia for procedures on the integumentary system on the extremities, anterior trunk and perineum; not otherwise specified) with 3 base units. Because the patient must be prone or lateral to allow the surgeon to reach that area, you can add 2 additional units and bill for 5 total base units.
 

The patient is in the prone position during an elbow procedure so the surgeon can reach the right part of the elbow. Add 2 more units to code 01730 (Anesthesia for all closed procedures on humerus and elbow) if the anesthesiologist documents position or field avoidance.
 

The patient is in the prone position during surgery to repair a calcaneal (heel) fracture. Both anesthesia codes for the procedure (01462, Anesthesia for all closed procedures on lower leg, ankle and foot; and 01480, Anesthesia for open procedures on bones of lower leg, ankle and foot; not otherwise specified) are 3 base units. You would raise either code to 5 units because of the patient's prone position.

As you study the chart, check whether the surgeon changed the patient's position at some point during the procedure. While this is not a common occurrence, it also isn't completely unheard of - especially for some cases involving multiple procedures during the same session (such as a mastectomy followed by reconstruction involving the latissimus dorsi).

"The surgeon may wish to have the patient's position changed at any given time during a surgical procedure," Johnson says. Because of that, a case that begins in the standard supine position might merit extra units for field avoidance before the procedure ends.

Charge the Correct Amount

Determining how much more to charge for field avoidance cases can be as challenging as identifying the cases themselves. The American Society of Anesthesiologist's Relative Value Guide addresses the issue in its Anesthesia Guidelines section: "Any procedure around the head, neck or shoulder girdle, requiring field avoidance, or any procedure requiring a position other than supine or lithotomy, has a minimum Basic Value of 5 regardless of any lesser basic value assigned to such procedure in the body of the Relative Value Guide."
 
Bottom line: That means you can charge 5 base units for a procedure meeting the criteria even if it is normally less than 5 base units.

ASA has adjusted the base unit value on most procedures above the "head, neck and shoulder girdle" to reflect the 5-unit base for field avoidance. One exception is 00126 (Anesthesia for procedures on external, middle and inner ear including biopsy; tympanotomy), which is a 4-unit procedure.
 
Some coders believe the tympanotomy qualifies for field avoidance units, noting that it is a procedure around the head and that the anesthesiologist might not be able to sufficiently reach the airway when the surgeon has the patient's head turned away. Caution: Other experts disagree, saying that the anesthesiologist's standard technique during these procedures (using a mask) means he always has control of the patient's airway. Talk with your anesthesiologist about these types of cases to determine whether charging extra units is appropriate.

CPT does not include modifiers to indicate field avoidance, so you must add the extra units yourself (assuming the procedure's original value is less than 5).  However, Glancy points out that some carriers might have guidelines for reporting field avoidance, so verify that you're doing it correctly.

Example: Arkansas Medicaid wants you to append modifier -22 (Unusual procedural services) when you bill for field avoidance. California's Medi-Cal has modifier -ZA (Prone position or surgical field avoidance) to designate field avoidance.

Johnson recommends taking verification a step further: "Some carriers may require modifiers for field avoidance. I strongly recommend that you get this in writing to avoid any compliance issues later."