Revenue Cycle Insider

Billing for base units is just the beginning.

Are you new to anesthesia coding? Or are you looking for a flawless system to create denial-proof anesthesia claims? Either way, following the steps outlined in  “How to Succeed With Coding and Billing Anesthesia Services,” a HEALTHCON 2024 session presented by Mary Garuccio, CANPC, CPMA, CPC, AAPC Fellow, ACS-AN, owner of Advanced Medical Practice Management LLC and senior consultant for RMA in North Carolina; and Dr. Laura McNeill, anesthesiologist at Allegheny General Hospital in Pittsburgh, will help improve your anesthesia coding and billing.

Here are the five steps they suggested, along with some of their expert analysis.

Get Back to the Basics

Anesthesia service formulation is built on five components, according to Garuccio and McNeill:

• Base unit
• Time
• Physical status
• Qualifiers, such as emergency or age
• Things not in the formulation, such as Swan-Ganz or central venous catheters, which can be billed separately

Here’s the way Garuccio and McNeill break these steps down.

Step 1: Understand the Base Unit

Simply put, base units are the CPT^® or HCPCS codes you will use to provide details of the basic service the anesthesiologist has provided to the patient. Importantly, before you assign a base code, remember what the service does, and does not, include. Per Garuccio and McNeill, anesthesia services are comprised of some, if not all, of the following:

• Transporting, positioning, prepping, and draping the patient
• Placement of external devices including, but not limited to, those for cardiac monitoring, oximetry, temperature monitoring, and so on
• Placement of peripheral intravenous lines for fluid and medication administration
• Placement of endotracheal, orotracheal, nasogastric, or orogastric tubes
• Laryngoscopy for placement of airway
• Interoperative interpretation of monitored functions
• Interpretation of lab determinations
• Nerve stimulation for determination of level of paralysis
• Insertion of urinary bladder catheter
• Blood sample procurement

(For a comprehensive list, check out the Anesthesia Services chapter of Medicare’s National Correct Coding Initiative Policy Manual. And be sure to check the document every year for any changes).

Step 2: Get Time on Your Side

Both the AMA and the American Society of Anesthesia (ASA) define time as beginning with patient prep and ending when the patient is safely placed under postoperative care. Usually, this is start-to-end time, though it can sometimes be discontinuous.

Overlook this step at your peril. “This is a huge factor in building your anesthesia charge,” according to Garuccio.

Step 3: Assign Physical Status

Sometimes known as an ASA or a PS rating, your next step in formulating the anesthesia service is to assign a physical status (PS) modifier using the ASA Physical Status Classification System.

CPT^® lists six PS modifiers:

• P1: A normal healthy patient
• P2: A patient with mild systemic disease
• P3: A patient with severe systemic disease
• P4: A patient with severe systemic disease that is a constant threat to life
• P5: A moribund patient who is not expected to survive without the operation
• P6: A declared brain-dead patient whose organs are being removed for donor purposes

Of the six, P3, P4, and P5 add units to the base units already assigned to the service.

Remember: Medicare and other payers don’t recognize physical status modifiers, regarding them as just informational, according to Garuccio. Currently, some of the Blue Cross carriers are following suit and discontinuing paying for them, so it’s important to check your carrier guidelines regarding how the modifier will affect your payment.

Regardless of payment, however, if your payer does require adding the modifier, the modifier may also require an ICD-10-CM code to support it. Additionally, “only the clinician taking care of the patient should assign the status — you can suggest one, but you have to query your provider,” McNeill emphasized.

Step 4: Understand Qualifying Circumstances Add-On Codes

Garuccio then noted that you can add on extra units when the circumstances listed in the anesthesia add-on code descriptors are met:

• For +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)), add 1 additional unit
• For +99116 (Anesthesia complicated by utilization of total body hypothermia (List separately in addition to code for primary anesthesia procedure)), add 5 additional units
• For +99135 (Anesthesia complicated by utilization of controlled hypotension (List separately in addition to code for primary anesthesia procedure)), add 5 additional units

When the patient undergoes treatment for an emergency condition, such as an emergency C-section when the baby is in fetal distress, a ruptured aneurysm, or trauma — basically, any situation where a delay in treatment would lead to a significant increase in the threat to life, McNeill noted you should use add-on code +99140 (Anesthesia complicated by emergency conditions (specify) (List separately in addition to code for primary anesthesia procedure)).

Pay attention to the note accompanying +99100, which tells you to use 00326 (Anesthesia for all procedures on the larynx and trachea in children younger than 1 year of age), 00561 (Anesthesia for procedures on heart, pericardial sac, and great vessels of chest; with pump oxygenator, younger than 1 year of age), 00834 (Anesthesia for hernia repairs in the lower abdomen not otherwise specified, younger than 1 year of age), or 00836 (Anesthesia for hernia repairs in the lower abdomen not otherwise specified, infants younger than 37 weeks gestational age at birth and younger than 50 weeks gestational age at time of surgery) instead of +99100 when appropriate.

Step 5: Know What You Can Bill Separately

CPT^® adds that “supplies and materials provided (eg, sterile trays, drugs) over and above those usually included with the office visit or other services rendered may be listed separately … and identified with 99070 [Supplies and materials … over and above those usually included with the office visit or other services rendered (list drugs, trays, supplies, or materials provided)] or the appropriate supply code.”

CPT^® also notes that “Unusual forms of monitoring (eg, intra-arterial, central venous, and Swan-Ganz) are not included” in anesthesia services, and should also be billed separately.

Next month: In Part 2, we’ll look at types of anesthesia and delivery, complex anesthesia, positioning, documentation, and more!

Bruce Pegg, BA, MA, CPC, CFPC, Managing Editor, AAPC