Billing code 37600: Carotid ligationMedicare rate & RVUs in Oregon
Reports operative ligation of the external carotid artery when a surgeon needs to interrupt its blood flow, such as for control of head-and-neck bleeding.
CMS doesn’t publish an office rate for 37600 in Oregon.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 9 sections
What 37600 covers
The surgeon exposes and ties off the external carotid artery in the neck to interrupt blood flow to its branches. The operation may be performed to control severe bleeding in the head or neck or when operative management requires control of external-carotid inflow. Vascular, otolaryngology, and head-and-neck surgeons typically perform it in a hospital operating room.
Choose this code when the artery ligated is the external carotid, rather than the internal or common carotid. The operative report should identify the artery and document the ligation and clinical purpose. The 90-day global period includes the day-before preoperative visit and 90 days of related postoperative care. For multiple procedures in the same session, the highest-valued procedure is paid in full and the others at 50%. Modifier 50 is inappropriate. An assistant at surgery may be paid; co-surgeons require supporting documentation, and team surgery is not permitted.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
Where 37600 pays more and less in Oregon
| Payment locality | Office | Facility |
|---|---|---|
| Portland | Unavailable | $671.32 |
| Rest Of Oregon | Unavailable | $640.46 |
How the 37600 rate is calculated
Each of 37600’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 37600
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 12.11Practice expense 5.59Malpractice 2.13
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 37600
37600 has a 90-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 37600
Carotid ligation
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 090 | Major surgery: the day before, the day of, and 90 days after are included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 2 | Paid. |
| Co-surgeons (62) | 1 | Permitted with supporting documentation. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
| Split (54/55/56) | 0.09/0.84/0.07 | Share of the payment for pre-op, the procedure itself, and post-op care. |
Global surgery period · 37600
Carotid ligation
90-day global period ends
Dec 30, 2026
Covers Sep 30, 2026 through Dec 30, 2026 (92 days, including the day before surgery).
Visit on Oct 31, 2026
Day 30 of the 90-day post-op period: related follow-up care is included in the surgical payment.
Pre-op dayGlobal period
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
37600 without 51 · national facility
$662.34
Carotid ligation
37600-51 · Second procedure: 50%
$331.17
When this isn’t the highest-valued procedure in the session, Medicare pays 50% of its fee schedule amount (the highest is paid at 100%).
37600 compared with similar codes
Compare codes
37600 vs 37605 vs 37606 vs 37615: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 37605Carotid ligation
- Use 37605 for ligation of the internal or common carotid artery; 37600 is specific to the external carotid.
- 37606Carotid ligation
- This code covers ligation or occlusion involving the internal or common carotid artery, not the external carotid.
- 37615Arterial ligation
- This code applies to ligation of a major artery in the neck when the procedure is not the specific external carotid service reported with 37600.
37600 billing questions
How does 37600 differ from ligation of the internal or common carotid?
Use 37600 when the external carotid artery is ligated. Codes 37605 and 37606 address the internal or common carotid instead.
What documentation supports reporting 37600?
The operative report should identify the external carotid artery, describe its exposure and ligation, and state the clinical reason for interrupting its blood flow.
Can modifier 50 be used for bilateral ligation?
No. The CMS bilateral adjustment does not apply to this code, and modifier 50 is inappropriate.
Is related postoperative care included?
Yes. The 90-day global period includes the day-before preoperative visit and 90 days of related postoperative care.
How are other procedures in the same session paid?
The highest-valued procedure is paid in full, and other procedures in the same session are subject to the standard 50% multiple-procedure reduction.
Can an assistant or co-surgeon be reported?
An assistant at surgery may be paid. Co-surgeons are paid only when supporting documentation is provided; team surgery is not permitted.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
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