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Keeping Current with ASC Coding/Payment Guidelines

In our latest Aidéo Coding Blog, our Director of Coding and Compliance Marsha Diamond is joined by Kris Brown, Director of Coding at Surgical Notes. Kris and Marsha discuss why keeping up with coding complexities and changes in the Ambulatory Surgical Center market is essential to a successful operation, no pun intended!

The following are some common issues/concerns in the ASC setting:

2024 Coding Updates Relating to ASCs:

Common Inpatient only procedures changed to ASC per 2024 CMS Final Rule:

▪ 21194 (Reconstruction of mandibular rami, horizontal, vertical, c, or l osteotomy; with bone graft (includes obtaining graft))

▪ 21195 (Reconstruction of mandibular rami and/or body, sagittal split; without internal rigid fixation)

▪ 23470 (Arthroplasty, glenohumeral joint; hemiarthroplasty)

▪ 23472 (Arthroplasty, glenohumeral joint; total shoulder (glenoid and proximal humeral replacement (eg, total shoulder))

▪ 27006 (Tenotomy, abductors and/or extensor(s) of hip, open (separate procedure))

▪ 27702 (Arthroplasty, ankle; with implant (total ankle))

▪ 29868 (Arthroscopy, knee, surgical; meniscal transplantation (includes arthrotomy for meniscal insertion), medial or lateral

▪ 33289 (Transcatheter implantation of wireless pulmonary artery pressure sensor for long-term hemodynamic monitoring, including deployment and calibration of the sensor, right heart catheterization, selective pulmonary catheterization, radiological supervision and interpretation, and pulmonary artery angiography, when performed)

▪ 37192 (Repositioning of intravascular vena cava filter, endovascular approach

including vascular access, vessel selection, and radiological supervision and interpretation, intraprocedural roadmapping, and imaging guidance (ultrasound and fluoroscopy), when performed)

▪ 60260 (Thyroidectomy, removal of all remaining thyroid tissue following previous removal of a portion of thyroid)

▪ C9734 (Focused ultrasound ablation/therapeutic intervention, other than uterine leiomyomata, with magnetic resonance (mr) guidance)

(This is NOT a complete list, refer to Table 7 – CMS 2024 ASC Procedures)

  • Addition of Dental Codes (D codes) in lieu of unlisted code 41899 for dental procedures (See Table 6 – CMS 2024 ASC Procedures)
  • Addition of G0330 for Facility Services Dental Rehab

Coding of Lesion Sizes

A considerable amount of revenue can be lost when lesion sizes are not documented appropriately.   For instance, if the lesion size is not documented, and the coder is forced to utilize the smallest size, the difference between the actual size and the coded size may be quite significant.

For this reason, it is imperative that your providers document lesion size.  According to the AHA, utilizing the size listed in the pathology report is not considered a true representation of the size of the lesion at the time of removal.   Also, CPT guidelines specifically state that the size of the lesion should be determined by the surgeon at the time of the actual excision.  Note that the size of the incision is not necessarily synonymous with the lesion size, so, pay careful attention to the size of the lesion, not the incision.   This applies to flaps and grafts as well, so it is important the surgeon document those at the time of the procedure as well.

This can effectively be achieved by adding to the lesion excision “template” your providers are utilizing that prompts for a lesion size in centimeters as required for coding.

OPPS Devices Added to Pass Through List

With the January 2024 update, five new devices for pass-through status were established in the ASC payment system. Please see Table below and note that HCPCS code C1604 (Grft, trnsmurl/trnsvens byps), which was newly approved for pass-through status under the OPPS effective January 1, 2024, is not eligible to be payable in ASCs.


HCPCS CodeShort DescriptorLong DescriptorASC PI
C1600Cath, bladed, vasc prepCatheter, transluminal intravascular lesion preparation device, bladed, sheathed (insertable)J7
C1601Endo, single, pulmonaryEndoscope, single-use (i.e. disposable), pulmonary, imaging/illumination device (insertable)J7
C1602Orth/matrx/bn fill drug-elutOrthopedic/device/drug matrix/absorbable bone void filler, antimicrobial-eluting (implantable)J7
C1603Ret dev, laser, ivc filterRetrieval device, insertable, laser (used to retrieve intravascular inferior vena cava filter)J7


Expiration of OPPS Pass Through Devices

The following have expired effective January 1, 2024

• C1825 Generator, neurostimulator (implantable), non-rechargeable with carotid sinus baroreceptor stimulation leads

• C1052 Hemostatic agent, gastrointestinal, topical

• C1062 Intravertebral body fracture augmentation with implant (e.g. metal, polymer)

• C1734 Orthopedic/device/drug matrix for opposing bone-to-bone or soft tissue-to-bone (implantable)

• C1824 Generator, cardiac contractility modulation (implantable)

• C1839 Iris prosthesis

• C1982 Catheter, pressure-generating, one-way valve, intermittently occlusive

• C2596 Probe, image-guided, robotic, waterjet ablation

New Skin Substitutes

See Table 9 and 10 CMS 2024 ASC Procedures for a complete listing

Covered Implants/Supplies

This list would vary greatly based on location, MAC, insurance payor and many other factors. We would suggest referencing your individual MAC website or payor website and compiling a listing of payable implants and supplies, prompting your documentation templates to require appropriate documentation so these implants/supplies can be captured when appropriate.

Collaborating Authors:

Director, Coding, Surgical Notes

Marsha S. Diamond, CPC, COC, CCS, CPMA, former AAPC Fellow
Director, Coding and Compliance, Aidéo Technologies