CPT code 00352: Anesthesia for simple ligation of major neck vessels

Key Takeaways

CPT code 00352 describes anesthesia for simple ligation of a major vessel of the neck, maintained by the American Medical Association (AMA).

Base units are set at 5, half the 10 base units assigned to the broader CPT code 00350 for other major neck vessel procedures; reimbursement uses the formula (Base Units + Time Units) x Conversion Factor.

Physical status modifiers P1 through P6 and qualifying circumstance modifiers AA, QK, QX, QY, and QZ must be appended correctly to avoid claim denial. Medicare does not pay extra units for physical status modifiers, though many commercial payers do.

Pabau’s claims management software supports accurate anesthesia billing workflows, from CPT code assignment through documentation and invoice generation.

A neck laceration comes into the ER, the surgeon ties off a bleeding vessel in minutes, and the case is done almost before the anesthesia clock starts. Billing CPT code 00352 correctly is rarely that quick.

Confuse it with its close neighbor CPT code 00350, miss a single modifier, or leave a time detail undocumented, and the claim comes back denied. This guide covers exactly what 00352 means, how it differs from nearby codes, and what payers expect before they release payment.

CPT code 00352: Definition and clinical description

CPT code 00352 is the code for anesthesia administered during a simple ligation of a major vessel of the neck — a narrower, lower-complexity scenario than most people assume, and easy to confuse with the higher-value CPT code 00350.

The American Medical Association (AMA) maintains the CPT code set and assigns 00352 the official descriptor: Anesthesia for procedures on major vessels of neck; simple ligation. This places it within the anesthesia section (00100-01999) of the CPT code set, specifically within the 00300-00352 subrange covering neck procedures.

00352 applies when a qualified anesthesia provider administers anesthesia for a straightforward ligation (tying off) of a major cervical vessel, such as the external carotid artery or a jugular vein, most often to control hemorrhage.

It does not cover carotid endarterectomy, vascular reconstruction, bypass, or other complex open procedures on major neck vessels; those map to CPT 00350.

It also does not cover catheter-based interventions like carotid artery stenting, which are typically billed under CPT 01925 instead. Coders working in surgical EMR workflows bill 00352 far less often than 00350, precisely because most major neck vessel cases are more involved than a simple ligation.

CPT 00352 code details at a glance

Use this quick-reference table before billing to confirm the code’s key data points. All values should be verified against the current AMA CPT code book and CMS fee schedule for the applicable fiscal year.

Base units for CPT code 00352

CPT code 00352 carries an assigned base unit value of 5. Base units are a fixed number assigned by the AMA that reflects the inherent complexity, skill, and risk associated with providing anesthesia for a given procedure category.

Simple ligation of a major neck vessel still carries risk because of the anatomical proximity to critical structures, but it is a lower-complexity intervention than the open, reconstructive procedures billed under CPT 00350 (10 base units).

Those procedures are typically performed to repair, bypass, or reconstruct the vessel rather than to control hemorrhage, which is reflected in 00352’s base-unit value of exactly half of 00350’s.

Base units do not change with case duration. They represent the floor value before time is added. Every CPT anesthesia code has a fixed base unit count.

00352’s value of 5 is the lowest among the major-vessel-neck codes, reflecting that simple ligation is a narrower and less extensive intervention than the “not otherwise specified” procedures billed under 00350.

Always confirm base units against the current AMA CPT code book or CMS data file for the applicable calendar year, as the AMA may revise values in annual updates.

Base units vary widely across the anesthesia code range depending on procedure complexity. CPT 00218, for intracranial procedures performed in the sitting position, carries a much higher value than 00352.

CPT 01654, for example, covers shoulder and axilla artery bypass graft procedures, while CPT 01830 covers anesthesia for forearm, wrist, and hand procedures. These variations illustrate how the AMA calibrates base units to anatomical risk and procedural complexity rather than time alone.

How anesthesia reimbursement is calculated for CPT code 00352

Anesthesia reimbursement does not follow the standard RVU model used for evaluation and management or surgical codes. Instead, it uses a time-based formula that adds base units to time units, then multiplies by a payer-specific conversion factor.

Worked example: A simple ligation of the external carotid artery, performed to control post-traumatic neck hemorrhage, runs 45 minutes. The anesthesia provider bills CPT code 00352 with 5 base units plus 3 time units (45 min / 15 = 3), for a total of 8 units.

At the CY2026 Medicare anesthesia conversion factor of $20.4976 per unit, the calculation yields (5 + 3) x $20.4976 = $163.98 before modifier adjustments.

That rate is up 0.88% from the CY2025 conversion factor of $20.3178 per unit, though it remains below the $20.68 per unit rate in effect for most of CY2024, after a mid-year revision from $20.43 under the Consolidated Appropriations Act, 2024.

Use the FastRVU 2026 lookup tool to verify current RVU and reimbursement figures by locality, since private payer conversion factors often exceed Medicare rates.

Medicare rates for CPT code 00352

Medicare calculates anesthesia payment using the formula above, with the conversion factor set annually through the Medicare Physician Fee Schedule (MPFS).

For CY2026, CMS finalized a national Medicare anesthesia conversion factor of $20.4976 per unit for most clinicians, up 0.88% from the CY2025 rate of $20.3178 per unit. A separate rate of $20.5998 per unit applies to clinicians participating in Advanced Alternative Payment Models.

Both figures are adjusted by geographic locality using the Geographic Practice Cost Index (GPCI). For comparison, CY2024 saw a mid-year revision: CMS initially finalized approximately $20.43 per unit from January 1 through March 8, 2024, before the Consolidated Appropriations Act, 2024 raised it to approximately $20.68 per unit for the rest of that year.

For CPT code 00352 with 5 base units, a 60-minute procedure yields a total unit count of 9 (5 base + 4 time units). At the CY2026 national rate of $20.4976 per unit, that produces a Medicare payment of approximately $184.48 before any qualifying circumstance modifier adjustments, compared with approximately $186.12 for the same case at the CY2024 rate of $20.68 per unit.

A 120-minute case would total 13 units (5 base + 8 time units), yielding approximately $266.47 at the current rate. Rates change annually. Verify the current conversion factor through the CMS Physician Fee Schedule before billing.

Modifiers for CPT code 00352

Anesthesia codes require two categories of modifiers on every claim: qualifying circumstance modifiers that identify who performed the service, and physical status modifiers that reflect the patient’s health complexity. Missing either category is a common trigger for claim denial.

Qualifying circumstance modifiers (AA, QK, QX, QY, QZ)

Physical status modifiers for CPT code 00352 (P1-P6)

The American Society of Anesthesiologists (ASA) defines six physical status classifications. Every anesthesia claim, including those using CPT code 00352, must carry the appropriate physical status modifier to reflect the patient’s health at the time of service.

Some payers add extra units to the claim for physical status modifiers P3, P4, and P5, to reflect the additional monitoring and clinical complexity those patients require. Medicare is the exception: CMS does not recognize or pay additional units for physical status modifiers, treating the P modifier as informational only on Medicare claims.

Many commercial and private payers do add units for P3 through P5, so check the specific payer contract before assuming the extra units will be reimbursed.

Patients requiring emergency ligation of a major neck vessel to control trauma-related hemorrhage often present with cardiovascular or other comorbidities that support a P3 or P4 classification.

Documenting the physical status accurately still matters for medical necessity and audit purposes, even where it doesn’t change the Medicare payment.

ICD-10 codes commonly used with CPT code 00352

Medical necessity for CPT code 00352 must be supported by a diagnosis code that identifies the condition requiring the vessel ligation. Payers cross-reference the anesthesia CPT code against the ICD-10-CM diagnosis code on the claim. A mismatch, or a diagnosis that does not support the procedure, results in denial.

Because simple ligation of a major neck vessel is most often performed for trauma or hemorrhage control, the diagnoses paired with CPT 00352 skew toward acute vascular injury rather than the elective vascular disease diagnoses paired with CPT 00350.

Neck vessel trauma severe enough to require ligation can also involve cerebrovascular extension. Anesthesia teams may separately document this under CPT 00216 when intracranial vascular involvement requires its own anesthesia coverage. Below are the most commonly paired diagnoses.

Verify all ICD-10-CM codes against the current-year CMS tabular list before billing. Codes are updated annually, and deprecated codes submitted on claims generate automatic rejections.

Related CPT codes in the 00300-00352 range

Selecting the wrong code within the neck anesthesia range is one of the more common coding errors in this specialty. Use the AAPC Codify tool to cross-reference codes when the procedure note is ambiguous. The table below covers the most relevant codes in the 00300-00352 subrange.

CPT 00350 vs CPT 00352: What is the difference?

Both codes describe anesthesia for procedures on major vessels of the neck, but they are not interchangeable and do not share a base value. CPT 00350 carries the qualifier “not otherwise specified” and is valued at 10 base units, reflecting its use for more complex major vessel work such as carotid endarterectomy and open vascular reconstruction.

CPT code 00352 is the narrower “simple ligation” code and is valued at only 5 base units, reflecting the lower complexity of tying off a vessel rather than reconstructing or repairing it.

Catheter-based carotid artery stenting is typically reported under CPT 01925, not either 00350 or 00352, since it is an endovascular rather than open procedure. Choosing between 00350 and 00352 comes down to what the operative note actually describes.

If the surgeon performs an endarterectomy, bypass, or other reconstructive procedure, 00350 applies. If the note describes ligation only, 00352 applies. Choosing the most specific code the documentation supports keeps the claim aligned with payer expectations.

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Documentation requirements for CPT code 00352

Anesthesia claims are audited more frequently than most CPT categories because of the time-based billing model. Every minute on the claim is a verifiable data point, which means missing documentation translates directly into audit findings and recoupment demands.

The checklist below reflects current ASA and CMS documentation standards. Payer-specific requirements may vary.

• Pre-anesthesia evaluation: Documented assessment of patient health status, airway, relevant history, and assigned ASA physical status classification (P1-P6) before the procedure begins.
• Anesthesia start and stop times: Precise times documenting when anesthesia was induced and when the patient was released to post-anesthesia care. These support the time unit calculation on the claim.
• Intraoperative monitoring record: Continuous record of vital signs, oxygen saturation, end-tidal CO2, and other monitored parameters throughout the case.
• Personnel documentation: Identification of all anesthesia providers present, their roles (anesthesiologist, CRNA, AA), and the supervision or medical direction arrangement, which determines which qualifying circumstance modifier applies.
• Physical status modifier justification: Clinical notes supporting the assigned P modifier. Medicare does not add units for P modifiers, but many commercial payers do for P3-P5 classifications, so the supporting documentation still needs to be in the record.
• Post-anesthesia note: A brief note confirming the patient’s status at the conclusion of anesthesia care, typically the handoff to recovery.

Maintaining structured anesthesia records is where many practices struggle. Efficient HIPAA compliance requires that these records are stored securely and retrievable for audit. Practice management software like Pabau centralizes clinical documentation through its patient record management tools, so start/stop times, physical status notes, and provider credentials stay linked to the correct patient encounter.

Practices working across specialties, including those using ADHD screening CPT codes, benefit from this same centralized documentation approach.

Common billing errors to avoid with CPT code 00352

Four billing mistakes account for the majority of claim denials on CPT code 00352 claims. Each is preventable with the right documentation and billing review process.

• Missing qualifying circumstance modifier: Submitting 00352 without AA, QK, QX, QY, or QZ is an automatic denial for most payers. The modifier tells the payer who performed the service and at what supervision level.
• Incorrect or absent physical status modifier: Leaving off the P modifier, or assigning P1 to a patient whose documentation supports P3 or P4, results in underpayment or denial. The modifier must match the pre-anesthesia assessment documented in the record.
• Time unit rounding errors: CMS rounds anesthesia time to the nearest unit (1 unit = 15 minutes). Some practices incorrectly round up consistently, which can be flagged as overbilling during audits. Follow the payer’s rounding rules and document start/stop times to the minute.
• Confusing 00352 with 00350: Billing the simple-ligation code 00352 for a case that actually involved endarterectomy, bypass, or other vascular reconstruction understates the work performed and can trigger a denial or a payer audit once the operative note is reviewed. Confirm which code the documentation supports before submitting the claim, not after.

Practices billing complex surgical anesthesia alongside other specialty codes, such as IVF CPT codes used by fertility clinic software users, find that a centralized billing review step catches these errors before claims are submitted.

How Pabau supports anesthesia billing workflows

Coding reference pages explain what CPT code 00352 means. Billing software handles what happens next. Practices using Pabau connect the code-selection step directly to invoice generation, documentation storage, and claims submission without switching between systems.

Pabau’s claims management software supports accurate CPT code assignment alongside modifier tracking, so anesthesia bills leave the practice with the correct qualifying circumstance and physical status modifiers attached.

The digital clinical forms feature lets anesthesia teams build structured pre-anesthesia assessments that capture ASA physical status, start and stop times, and provider credentials in a consistent format, reducing the audit risk that comes from free-text anesthesia records.

Those records stay linked to the patient encounter through Pabau’s centralized record system, making them retrievable when payers request supporting documentation. Pabau’s automated billing workflows can also flag incomplete anesthesia records before a claim is submitted, catching missing modifier fields at the point of documentation rather than after a denial arrives.

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Conclusion

CPT code 00352 is straightforward in concept but demanding in execution. Five base units, the correct qualifying circumstance modifier, an accurately assigned physical status classification, and precise start/stop time documentation all have to align for the claim to pay without review.

Because 00352 is easy to confuse with the higher-valued 00350, most denials on this code trace back to code selection and missing documentation rather than time-unit math, which makes the practice’s record-keeping process as important as coder knowledge.

Pabau’s structured documentation tools, claims management workflows, and modifier-tracking features help anesthesia and surgical practices match what the code requires to what the record actually contains.

If your team is billing CPT code 00352 regularly, book a demo to see how Pabau supports anesthesia billing from documentation through to payment reconciliation.

Frequently asked questions