CPT code 00211 describes anesthesia services provided during an intracranial procedure — specifically a craniotomy or craniectomy performed for the purpose of evacuating a hematoma (a localized collection of blood within the cranial cavity). This code is reported by the anesthesia provider — an anesthesiologist, Certified Registered Nurse Anesthetist (CRNA), or Anesthesiologist Assistant (AA) — and encompasses all anesthetic care furnished from pre-induction through emergence and transfer to post-anesthesia care. It is one of the more frequently encountered codes in neurosurgical anesthesia billing, particularly in trauma settings and emergency surgery cases involving epidural, subdural, or intracerebral hemorrhage.
What Does CPT Code 00211 Mean?
CPT 00211 falls within the anesthesia code range for procedures performed on the head (00100–00222) and carries an official AMA descriptor of: Anesthesia for intracranial procedures; craniotomy or craniectomy for evacuation of hematoma. The code was added to the CPT code set effective January 1, 2009, splitting off from the broader CPT 00210 (intracranial procedures, not otherwise specified) to provide greater specificity for hematoma-evacuation procedures.
Key attributes of this code:
- Billable provider types: Anesthesiologists (MD/DO), CRNAs, and Anesthesiologist Assistants
- Applicable setting: Hospital inpatient operating room; hospital outpatient (rare for this case type); ambulatory surgical center (uncommon)
- Service category: Anesthesia for neurosurgical procedures — head
- CMS base unit value: 10 anesthesia base units
- Code status: Active; no descriptor changes since original effective date
What Anesthesia Services Does CPT 00211 Cover?
CPT 00211 encompasses the complete anesthesia care continuum delivered by the anesthesia professional during a craniotomy or craniectomy for hematoma evacuation. This includes pre-operative patient assessment, induction, maintenance, and emergence from general anesthesia, as well as intraoperative hemodynamic monitoring and management.
Covered services and clinical presentations include:
- Anesthesia for evacuation of epidural hematoma following traumatic skull fracture
- Anesthesia for evacuation of subdural hematoma (acute, subacute, or chronic presentation requiring open surgical approach)
- Anesthesia for evacuation of intracerebral hematoma requiring craniotomy access
- Anesthesia for emergent and non-emergent hematoma evacuation in adult and pediatric patients
- Continuous intraoperative neurophysiologic monitoring support (anesthesia management component only)
- Pre-anesthetic evaluation, anesthesia induction, airway management, and post-anesthesia care oversight
What Does CPT 00211 Specifically Exclude?
The following services and scenarios fall outside the scope of CPT 00211:
- Burr hole procedures for hematoma drainage — those are reported with CPT 00214 (burr holes, including ventriculography) when anesthesia is required
- Stereotactic aspiration of hematoma without open craniotomy access — report CPT 00210 if no more specific code applies
- Intracranial vascular procedures (e.g., aneurysm clipping, AVM resection) — use CPT 00216
- Cerebrospinal fluid shunting procedures — use CPT 00220
- The surgical procedure itself — CPT 00211 is the anesthesia code only; the neurosurgeon separately reports the surgical CPT code (e.g., CPT 61312 or CPT 61314 for the open evacuation)
- Surgeon-administered anesthesia — if the operating neurosurgeon also administers anesthesia (unusual), Modifier 47 is appended to the surgical code, not 00211
When Is CPT 00211 the Right Code to Use?
Selecting CPT 00211 requires the anesthesia provider to verify that the clinical encounter meets specific criteria. In practice, coders frequently encounter situations where a trauma patient is rushed to the OR and the operative report defaults to describing a generic “craniotomy” — the documentation must be reviewed carefully to confirm the procedure was specifically for hematoma evacuation.
Apply CPT 00211 when ALL of the following criteria are met:
- The anesthesia provider delivered complete anesthesia services (not sedation or MAC without general anesthesia in the absence of unusual circumstances)
- The surgical procedure involved intracranial access via craniotomy (temporary skull opening) or craniectomy (skull bone removal without immediate replacement)
- The primary surgical objective was evacuation or removal of a hematoma — either epidural, subdural, or intracerebral
- A separate surgeon or neurosurgeon performed the operative procedure (the anesthesiologist did not also serve as the operating surgeon)
- The procedure took place in an appropriate surgical facility with standard intraoperative monitoring equipment
How Does CPT 00211 Differ From CPT 00210?
The most common coding confusion in this category is the use of CPT 00210 (intracranial procedures, not otherwise specified) when CPT 00211 is the correct, more specific choice. Using 00210 when 00211 applies is an upcoding risk in reverse — it can result in underpayment and documentation mismatch during audit.
| Feature | CPT 00210 | CPT 00211 |
|---|---|---|
| Official descriptor | Anesthesia for intracranial procedures; not otherwise specified | Anesthesia for intracranial procedures; craniotomy or craniectomy for evacuation of hematoma |
| Base units (CMS) | 11 | 10 |
| Specificity | Catch-all / NOS | Procedure-specific |
| Correct use case | Intracranial procedures not covered by a more specific code | Craniotomy or craniectomy specifically for hematoma evacuation |
| Audit risk when misused | Overcoding (11 vs. 10 base units) | Under-specificity; documentation mismatch |
| Introduced | Legacy code | Effective 01/01/2009 |
In practice: Coders should default to 00211 whenever the operative report documents a craniotomy or craniectomy performed to evacuate or decompress a hematoma. Reserve 00210 only for intracranial procedures where no more specific anesthesia code exists.
What Documentation Is Required to Support CPT 00211?
The anesthesia record is the primary documentation vehicle for justifying CPT 00211 and all appended modifiers. Auditors from Recovery Audit Contractors (RACs) and Medicare Administrative Contractors (MACs) focus heavily on anesthesia record completeness when reviewing high-complexity neurological cases.
What Must the Anesthesia Provider Document in the Anesthesia Record?
The anesthesia record must include all of the following to support CPT 00211:
- Pre-anesthetic evaluation: Patient history, physical examination findings, ASA physical status classification (P1–P6), and airway assessment documented before induction
- Anesthesia start time: The exact clock time when the anesthesia professional began preparing the patient for induction
- Surgical start and end time: Documented operative period to support time unit calculation
- Anesthesia end time: Clock time when the anesthesiologist or CRNA ended active anesthesia care
- Anesthetic agents administered: Type, dose, route, and timing of all agents (induction agents, volatile gases, neuromuscular blockade, analgesics)
- Intraoperative monitoring parameters: Continuous ECG, blood pressure, SpO₂, EtCO₂, temperature — recorded at regular intervals
- Airway management: Intubation method, tube size, confirmation of placement
- Provider identity and supervision status: Identifying the anesthesiologist, CRNA, or AA, along with any supervision arrangement (medical direction vs. independent) to support the applicable HCPCS modifier
- Post-anesthesia note: Brief documentation confirming transfer of care and patient status at emergence
How Do Physical Status and Qualifying Circumstance Modifiers Affect Documentation?
Physical status modifiers (P1–P6) and qualifying circumstance codes (99100, 99116, 99135, 99140) carry specific documentation requirements:
- P3–P6 modifiers require the pre-anesthetic evaluation to document the specific systemic disease or comorbidity that supports the classification — a general “complex patient” note is insufficient for audit purposes
- CPT 99140 (anesthesia complicated by emergency conditions) requires documentation that the surgical situation was emergent — the anesthesia record or operative note should reflect the time-sensitive nature of the intervention (e.g., “patient presented with acute neurological deterioration requiring emergent surgery”)
- CPT 99100 (extreme age: <1 year or >70 years) applies automatically when the patient’s age qualifies — the date of birth in the record serves as the supporting documentation
- Medicare does NOT reimburse separately for physical status modifiers P1–P6 or for qualifying circumstance codes 99100–99140 — these are bundled into the base unit payment under Medicare. Commercial payers vary: many do add physical status units (typically 1–2 additional base units per modifier) and do separately reimburse qualifying circumstances codes. Verify with each payer contract before billing.
How Does CPT 00211 Affect Anesthesia Billing and Reimbursement?
Anesthesia billing operates on a fundamentally different model than standard CPT procedure coding. Rather than a single fee-schedule allowable, reimbursement for CPT 00211 is calculated using the base unit + time unit formula, multiplied by a locality-specific anesthesia conversion factor.
The anesthesia payment formula:
(Base Units + Time Units) × Conversion Factor = Allowed Amount
For CPT 00211:
- CMS Base Units: 10
- Time Units: Calculated at 1 unit per 15 minutes of documented anesthesia time (some payers use 10- or 12-minute increments — confirm per contract)
- Conversion Factor: Set by CMS at the locality level annually; 2025 Medicare national average anesthesia conversion factor is approximately $22.17 per unit (verify current rates via the CMS Physician Fee Schedule lookup tool)
Illustrative example: For a 90-minute craniotomy procedure, time units = 6 (90 ÷ 15). Total billable units = 10 (base) + 6 (time) = 16 units. At a $22.17 conversion factor, the estimated Medicare allowable would be approximately $354.72. Note that actual reimbursement depends on locality, modifier, and payer-specific contract rates.
| Unit Component | CPT 00211 Value | Notes |
|---|---|---|
| CMS Base Units | 10 | Set nationally; does not vary by locality |
| Time Units | Variable | 1 unit per 15 min (Medicare); payers vary |
| Physical Status Units (P3) | +1 unit (commercial only) | Not separately paid by Medicare |
| Physical Status Units (P4) | +2 units (commercial only) | Not separately paid by Medicare |
| Qualifying Circumstance (99140) | +2 units (commercial only) | Not separately paid by Medicare |
| Anesthesia Conversion Factor | ~$22.17/unit (2025 national) | Locality-adjusted; verify via CMS PFS |
What Modifiers Are Commonly Used With CPT 00211?
CPT 00211 requires a provider-type modifier in the first modifier position for all Medicare claims. Physical status modifiers occupy the second modifier position.
| Modifier | Description | When to Apply | Reimbursement Impact |
|---|---|---|---|
| AA | Anesthesiologist personally performed | Anesthesiologist provides all care without supervision of another provider | 100% of allowed amount |
| QK | Medical direction of 2–4 concurrent cases | Anesthesiologist meets all 7 CMS medical direction steps | 50% of allowed amount (Medicare) |
| QY | Medical direction of 1 CRNA | Anesthesiologist directs a single CRNA | 50% of allowed amount (Medicare) |
| QX | CRNA under medical direction | CRNA performing; anesthesiologist directing | 50% of allowed amount (Medicare) |
| QZ | CRNA without medical direction | CRNA performing independently (where state law permits) | 100% of CRNA allowed amount |
| AD | Medical supervision >4 concurrent cases | Anesthesiologist supervises 5+ concurrent cases | 3 base units only (Medicare) |
| P1–P6 | ASA physical status classification | Always append to reflect patient status | Commercial payers: additional units; Medicare: informational only |
| 99100 | Qualifying circumstance: extreme age | Patient <1 year or >70 years at time of anesthesia | Commercial payers: +1 unit; Medicare: not separately reimbursed |
| 99140 | Qualifying circumstance: emergency | Documented emergent condition requiring urgent surgery | Commercial payers: +2 units; Medicare: not separately reimbursed |
| 23 | Unusual anesthesia | Procedure normally performed without general anesthesia requires GA due to unusual circumstances | Additional documentation required; payer-specific review |
Are There Any Prior Authorization, Coverage Restrictions, or Payer-Specific Rules?
- Emergency cases: CPT 00211 is frequently reported in emergent trauma settings where prior authorization is not possible. Most commercial payers have provisions for retroactive authorization in emergent neurosurgical situations — anesthesia billing teams should initiate notification within the payer’s required window (often 24–72 hours post-service).
- Medicare medical direction rules: For modifier QK and QY to be valid, the anesthesiologist must satisfy all seven CMS medical direction steps as outlined in the Medicare Claims Processing Manual, Chapter 12. Failure to document any step can result in the claim being downgraded to supervisory rates or denied.
- CRNA opt-out states: In states that have opted out of the Medicare physician supervision requirement for CRNAs, QZ claims are payable at 100% of the allowed amount without a supervising physician. In states that have not opted out, Medicare requires physician supervision of CRNAs.
- Concurrency limits: When an anesthesiologist is directing more than four concurrent cases (modifier AD), Medicare limits reimbursement to three base units per case — regardless of how many base units the procedure code carries.
What CPT or Surgical Codes Are Commonly Billed Alongside CPT 00211?
The anesthesia code (00211) is always reported alongside the surgical CPT code billed by the neurosurgeon. The two code sets are billed on separate claims by separate providers and do not bundle with each other. However, additional codes for qualifying circumstances and neurophysiologic monitoring may appear on the anesthesia claim.
| Associated Code | Description | Typical Pairing Context | Bundling Risk |
|---|---|---|---|
| CPT 61312 | Craniectomy/craniotomy — drainage of extradural/subdural hematoma | Primary neurosurgical code when anesthesiologist reports 00211 | No (separate claims) |
| CPT 61314 | Craniectomy/craniotomy — drainage of intracerebral hematoma | Alternative surgical code for intracerebral hematoma | No (separate claims) |
| CPT 99100 | Qualifying circumstance: anesthesia for extreme age | Elderly or pediatric patients; appended to 00211 | Medicare: bundled; commercial: separate |
| CPT 99140 | Qualifying circumstance: emergency conditions | Emergent presentations; appended to 00211 | Medicare: bundled; commercial: separate |
| CPT 01996 | Daily hospital management of epidural/subarachnoid drug administration | Post-op pain management following craniotomy | Separate claim; distinct service |
Which Code Combinations Require Careful Review for NCCI or Bundling Purposes?
- CPT 00211 and CPT 00210 should never be reported together for the same case — they are mutually exclusive codes for the same anatomical/procedural territory. Use the most specific code; 00211 supersedes 00210 for hematoma-evacuation craniotomies.
- Qualifying circumstance codes (99100, 99140) are legitimate add-ons to the anesthesia code for commercial payers, but must not be billed to Medicare as separately payable services — they are considered bundled under Medicare’s anesthesia payment policy.
- Review the CMS NCCI Policy Manual if billing anesthesia alongside neurophysiologic monitoring codes — payer bundling logic for intraoperative monitoring can vary significantly.
What Coding Errors Should You Avoid With CPT 00211?
Billing teams and credentialed coders should be aware of the following errors, ranked by audit frequency and compliance risk:
- Reporting CPT 00210 instead of 00211 for documented hematoma-evacuation craniotomies — 00210 is a catch-all code; using it when a specific code exists constitutes a specificity error and can flag claims for RAC review.
- Billing qualifying circumstance codes (99100, 99140) to Medicare — these codes are not separately reimbursable under Medicare and will be denied or require manual recoupment.
- Missing or incorrect provider-type modifier in the first modifier position — Medicare will reject anesthesia claims that do not carry AA, QK, QY, QX, QZ, or AD in the first modifier slot.
- Calculating time units incorrectly — using 15-minute units when the payer contract specifies 10-minute increments, or starting the anesthesia clock at incision rather than at the documented anesthesia start time.
- Failure to document all seven CMS medical direction steps when billing QK or QY — auditors have cited this as a top recovery target in anesthesia program integrity reviews.
- Omitting the physical status modifier — while P1–P6 modifiers are informational for Medicare, commercial payers may require them for claims adjudication and may deny or pend claims that lack them.
What Do Auditors Look for When Reviewing Claims With CPT 00211?
Auditors reviewing CPT 00211 claims — including RAC reviewers and OIG-initiated audits — flag the following patterns:
- Anesthesia time documentation gaps: Missing or illegible start/end times on the anesthesia record — the single most common technical denial trigger
- Medical direction non-compliance: Anesthesiologist documented as concurrently in more cases than modifier supports, or missing signature on any of the seven required steps
- Diagnosis-to-procedure mismatch: ICD-10-CM diagnosis codes that describe chronic or elective conditions rather than an acute hematoma (e.g., reporting a scheduled procedure under a code that implies emergent trauma)
- Unsubstantiated emergency modifier (99140): Qualifying circumstance billed without corresponding operative note language supporting the emergent nature of the case
- Duplicate billing: Both the anesthesiologist and CRNA billing separately under AA and QZ simultaneously — these are mutually exclusive modifier combinations
How Does CPT 00211 Relate to Other Intracranial Anesthesia Codes?
CPT 00211 is one of ten anesthesia codes in the 00210–00222 family covering intracranial procedures. Selecting the correct code requires understanding the procedural distinctions that define each one.
| Related Code | Procedure Type | Relationship to 00211 | Key Distinction |
|---|---|---|---|
| CPT 00210 | Intracranial procedures, NOS | Broader/catch-all | Use only when no specific code applies; 11 base units |
| CPT 00211 | Craniotomy/craniectomy for hematoma evacuation | Specific code | Primary subject of this guide; 10 base units |
| CPT 00212 | Subdural taps | Distinct procedure | Less invasive; 5 base units; no open skull access |
| CPT 00214 | Burr holes, including ventriculography | Distinct procedure | Burr hole only, not full craniotomy; 9 base units |
| CPT 00215 | Cranioplasty or elevation of depressed skull fracture | Distinct procedure | Skull reconstruction, not hematoma evacuation; 9 base units |
| CPT 00216 | Intracranial vascular procedures | Distinct procedure | Aneurysm, AVM; highest intracranial base units at 15 |
| CPT 00218 | Intracranial procedures in sitting position | Position-specific | Any intracranial procedure requiring sitting position; 13 base units |
| CPT 00220 | Cerebrospinal fluid shunting procedures | Distinct procedure | VP/LP shunt placement; 10 base units |
What Is the Correct Code Sequencing When Multiple Anesthesia Providers Are Involved?
When a case involves both a supervising anesthesiologist and a CRNA or AA, both parties submit their own claims for the same CPT code. Follow this reporting order:
- The anesthesiologist submits CPT 00211 with modifier QK (if directing 2–4 cases) or QY (if directing 1 CRNA)
- The CRNA or AA submits CPT 00211 with modifier QX (when under medical direction)
- Each provider bills their own time units — only the time each provider was personally attending the case is billable per provider
- If the anesthesiologist personally performs the entire case alone, modifier AA is used, and only one claim is submitted
- Physical status modifiers (P1–P6) are appended after the provider-type modifier in the second modifier position on each claim
- Only the single anesthesia code with the highest base unit value is reported when the same patient undergoes multiple anesthesia services in the same operative session on the same day — per CMS Medicare Claims Processing Manual, Chapter 12
Real-World Coding Scenario — How CPT 00211 Is Applied in Practice
A 74-year-old patient is brought to the emergency department after a ground-level fall with loss of consciousness. CT imaging confirms an acute subdural hematoma with significant midline shift. The neurosurgeon schedules the patient for emergent craniotomy. An anesthesiologist and a CRNA jointly manage the case: the anesthesiologist is present for induction and emergence and checks in at regular intervals, while the CRNA manages the case in between under medical direction. The case runs 110 minutes (anesthesia start to end). The patient is transferred to the neurological ICU post-operatively.
Correct Code Application
- Anesthesiologist claim: CPT 00211-QY-P3, CPT 99140 (emergency qualifying circumstance — commercial payer only), CPT 99100 (extreme age >70 — commercial payer only)
- CRNA claim: CPT 00211-QX-P3
- Time units: 110 minutes ÷ 15 = 7.33 → round to 7 (or per payer rounding rules)
- ICD-10-CM supporting diagnosis: S06.5X0A (traumatic subdural hemorrhage without loss of consciousness, initial encounter) plus injury mechanism code
- Both claims submitted under appropriate individual NPI; CRNA billed under supervising anesthesiologist’s NPI per Medicare policy
Common Mistake in This Scenario
- Error 1: Billing CPT 00210 instead of 00211 — the operative report clearly documents hematoma evacuation via craniotomy; 00210 is not appropriate and represents a specificity deficiency
- Error 2: Including CPT 99100 and 99140 on the Medicare claim — these qualifying circumstance codes are not separately reimbursed by Medicare and will be denied; removing them prevents recoupment
- Error 3: The anesthesiologist billing AA (personally performed) when a CRNA was also managing the case — AA is appropriate only when the anesthesiologist personally delivers all care throughout the case
- Error 4: Not documenting all seven medical direction steps in the anesthesia record — without this, the QY/QX pair will fail audit and the anesthesiologist’s claim may be reduced to a supervisory rate
Frequently Asked Questions About CPT Code 00211
Is CPT Code 00211 Still Valid for Use in 2025 and 2026?
CPT code 00211 remains an active, billable code with no descriptor changes since its effective date of January 1, 2009. Anesthesia coders should verify annually against the AMA CPT Professional Edition and the CMS Physician Fee Schedule to confirm that base unit values and reimbursement rates have not been revised for the current calendar year.
What Is the Difference Between CPT 00211 and CPT 00210?
CPT 00211 is the specific anesthesia code for craniotomy or craniectomy performed to evacuate a hematoma, while CPT 00210 is the “not otherwise specified” catch-all code for intracranial procedures not described by a more specific code. When the operative report documents hematoma evacuation via open cranial access, 00211 is always the correct choice; using 00210 in that scenario constitutes a coding specificity error and creates audit exposure.
How Many Base Units Does CPT 00211 Carry?
CPT 00211 carries 10 CMS anesthesia base units, as established in the CMS anesthesia base unit table. By comparison, CPT 00210 carries 11 base units and CPT 00216 (vascular intracranial procedures) carries 15 base units — reflecting the relative intensity and risk associated with each procedure type.
Can CPT 99140 (Emergency Qualifying Circumstance) Be Billed With CPT 00211?
CPT 99140 can be reported alongside CPT 00211 when there is documented evidence that the surgical situation constituted an emergency requiring immediate intervention. However, Medicare does not separately reimburse CPT 99140 — it is bundled into the base unit payment for the anesthesia code. Many commercial payers do accept it and add 2 base units to the total. Always verify with each payer’s specific anesthesia policy before billing 99140.
What Physical Status Modifier Should Be Used With CPT 00211 for a Trauma Patient With Intracranial Bleeding?
Most trauma patients presenting for emergent hematoma evacuation will qualify for P3 (patient with severe systemic disease — life threat not imminent) or P4 (patient with severe systemic disease that is a constant threat to life), depending on their neurological status, hemodynamic stability, and comorbidities at the time of surgery. The pre-anesthetic evaluation note must specifically document the clinical findings that support the assigned ASA physical status classification.
Do Both the Anesthesiologist and CRNA Submit CPT 00211 When Both Are Involved in a Case?
Yes — when an anesthesiologist medically directs a CRNA on a case, both providers submit separate claims using CPT 00211 with their respective provider-type modifiers (QY for the anesthesiologist directing one CRNA; QX for the CRNA under medical direction). Each claim is adjudicated at 50% of the applicable fee schedule for Medicare. The total combined reimbursement equals 100% of the allowed amount — split between the two providers.
What ICD-10-CM Diagnosis Codes Are Typically Reported With CPT 00211?
The supporting diagnosis codes depend on the type and cause of the hematoma. Common ICD-10-CM codes paired with anesthesia claims for CPT 00211 include S06.4X0A–S06.4X9A (epidural hemorrhage, various consciousness levels), S06.5X0A–S06.5X9A (traumatic subdural hemorrhage), I61.0–I61.9 (nontraumatic intracerebral hemorrhage by location), and I62.00–I62.9 (nontraumatic subdural hemorrhage). The diagnosis should match the reason for the surgery documented in the operative report and should establish medical necessity documentation for the emergent or planned procedure.
Key Takeaways for Billing and Coding CPT 00211
- CPT 00211 is the correct, specific anesthesia code for craniotomy or craniectomy performed to evacuate a hematoma — always prefer it over the non-specific CPT 00210 when the operative report confirms hematoma evacuation
- The CMS base unit value is 10 units; reimbursement is calculated using the formula: (base units + time units) × locality-specific conversion factor
- A provider-type modifier (AA, QK, QY, QX, QZ, or AD) is mandatory in the first modifier position on all Medicare and most commercial anesthesia claims
- Physical status modifiers P1–P6 are informational for Medicare but can yield additional base units from many commercial payers — always append them accurately
- Qualifying circumstance codes 99100 and 99140 are not separately payable by Medicare but are reimbursable by many commercial payers — verify each payer’s anesthesia policy
- When anesthesiologists medically direct CRNAs, both providers submit separate claims with the correct paired modifiers (QY + QX), each reimbursed at 50% of the allowed amount
- Anesthesia time documentation — accurate start and end times recorded in the anesthesia record — is the most frequently cited deficiency in coding audit preparation for intracranial anesthesia claims
For detailed anesthesia payment rules, consult the CMS Medicare Claims Processing Manual, Chapter 12 and the American Society of Anesthesiologists (ASA) Relative Value Guide for current base unit values and crosswalk guidance.
