Anesthesia Coding Alert

Did you catch the difference in base units for these anesthesia codes?

Knowing whether a procedure is performed as an injection or destruction by a neurolytic agent is just one factor involved in acing spinal anesthesia codes 01937-01942. The tips below will help increase your accuracy when a case calls for one of these new-for-2022 codes.

How Do You Choose the Right Code From 01937-01942?

Codes 01937-01942 represent anesthesia services for percutaneous image-guided procedures on the spine or spinal cord. To choose the correct anesthesia code, you need to know both the type of procedure the surgeon performed and the spinal area involved.

The list below shows that there are two anesthesia codes for each procedure type. The first code in each set applies to cervical or thoracic procedures, and the second code in each set applies to lumbar or sacral procedures.

• Injection, drainage, or aspiration procedures
  • 01937 (Anesthesia for percutaneous image-guided injection, drainage or aspiration procedures on the spine or spinal cord; cervical or thoracic)
  • 01938 (… lumbar or sacral)
• Destruction procedures by neurolytic agent
  • 01939 (Anesthesia for percutaneous image-guided destruction procedures by neurolytic agent on the spine or spinal cord; cervical or thoracic)
  • 01940 (… lumbar or sacral)
• Neuromodulation or intravertebral procedures
  • 01941 (Anesthesia for percutaneous image-guided neuromodulation or intravertebral procedures (eg, kyphoplasty, vertebroplasty) on the spine or spinal cord; cervical or thoracic)
  • 01942 (… lumbar or sacral)

These descriptors use the word “or” when listing the spine region, such as “cervical or thoracic.” But that doesn’t mean you should report two anesthesia codes if the session involves services for two spine regions. This applies whether the regions are in the same code (such as cervical and thoracic in 01937) or in different codes (such as thoracic in 01937 and lumbar in 01938).

Here’s why: CPT^® Anesthesia section guidelines state, “When multiple surgical procedures are performed during a single anesthetic administration, the anesthesia code representing the most complex procedure is reported. The time reported is the combined total for all procedures.”

Typically, in this situation, coders select among multiple applicable anesthesia codes based on which has the highest base units. When the base value is the same for multiple codes that apply to your case, you can choose which to report. But make sure “the code reported has a matching diagnosis code. For example, you wouldn’t want to report the cervical procedure with a lumbar diagnosis code,” says Kelly D. Dennis, MBA, ACS-AN, CANPC, CHCA, CPC, CPC-I, owner of Perfect Office Solutions in Leesburg, Florida.

Take Your Coding to the Next Level With Term Tips

Understanding the terminology in the code descriptors also will help you select the correct code with confidence. Keep these terms in mind as you code.

Percutaneous, image-guided: Codes 01937-01942 apply to percutaneous, image-guided procedures. A percutaneous approach is a minimally invasive approach through the skin. Image-guided means the surgical provider visualized the procedure using imaging guidance, such as fluoroscopy, computed tomography, ultrasound, or magnetic resonance.

Spinal anatomy: Choosing a code from 01937-01942 also requires you to identify the area of the spine involved in the procedure:

• Cervical: The cervical spine is basically the neck area. There are seven cervical vertebrae, labeled C1 to C7.
• Thoracic: The thoracic vertebrae make up the middle section of the spine, extending from the bottom of the neck to the bottom of the ribs. You may see these 12 vertebrae referred to as T1 to T12.
• Lumbar: The lumbar vertebrae extend from the bottom of the rib cage to the pelvis. These five vertebrae are labeled L1 to L5.
• Sacral: The sacrum is a triangular bone between the lumbar spine and the tailbone (coccyx). The sacrum has five fused segments, S1 to S5.

Aspiration: Along with injection and drainage, 01937 and 01938 also may apply to aspiration. This refers to removing by suction, such as using suction to get a specimen for examination by a pathologist.

As an example, the anesthesiologist may report 01937 when the surgical provider performs and reports 62268 (Percutaneous aspiration, spinal cord cyst or syrinx) under ultrasonic guidance reported using 76942 (Ultrasonic guidance for needle placement (eg, biopsy, aspiration, injection, localization device), imaging supervision and interpretation).

Neurolytic: Codes 01939 and 01940 reference “destruction procedures by neurolytic agent.” As an example, the anesthesiologist may report 01939 when the surgical provider reports 64633 (Destruction by neurolytic agent, paravertebral facet joint nerve(s), with imaging guidance (fluoroscopy or CT); cervical or thoracic, single facet joint).

“Examples of neurolytic agents are Botox^® and phenol,” says Dennis. To learn more about what counts as a neurolytic agent, look for reputable sources, she says, such as websites of respected hospitals or trusted clinical resources.

Neuromodulation: Codes 01941 and 01942 apply to anesthesia services for neuromodulation, which means alteration (modulation) of nerve (neuro) activity. An example of a surgical cross code is 63650 (Percutaneous implantation of neurostimulator electrode array, epidural).

Intravertebral: Codes 01941 and 01942 also can apply to anesthesia services for intravertebral procedures, such as vertebroplasty. Intravertebral means the procedure is within the vertebra (not to be confused with intervertebral, which means between the vertebrae). Vertebroplasty “is the process of injecting a material (cement) into the vertebral body to reinforce the structure of the body using image guidance,” according to CPT^® guidelines with the vertebroplasty codes.

Why Did CPT^® Add These Spinal Procedure Anesthesia Codes?

Prior to 2022, anesthesia coders chose between the following two spine-procedure codes:

• 01935 (Anesthesia for percutaneous image guided procedures on the spine and spinal cord; diagnostic)
• 01936 (… therapeutic)

The June 2022 CPT^® Assistant explains that the American Medical Association (AMA)/Specialty Society Relative Value Scale (RVS) Update Committee (RUC) Relativity Assessment Workgroup (RAW) recommended updating these coding options because practices may have reported therapeutic code 01936 inappropriately. As a result, the CPT^® 2022 code set deleted 01935 and 01936, and it replaced them with 01937-01942.

While 2021 codes 01935 and 01936 differed based on whether the main procedure was diagnostic or therapeutic, the six 2022 codes do not because the anesthesia work does not differ based on those factors, according to CPT^® Assistant.

Discover Which 2 Codes Have Higher Base Units

While deleted codes 01935 and 01936 had 5 base units, most of the replacement codes have 4 base units. Codes 01941 and 01942 are the exceptions with 5 units each. This difference is important because the basic Medicare formula to calculate the allowed amount for anesthesia includes base units:

(Base units + time [in units]) x anesthesia conversion factor = anesthesia fee amount.

Table 1 summarizes the codes, including the number of base units. The American Society of Anesthesiologists (ASA) and Medicare assign the same number of base units to these codes.