ModifiedPremera BluecrossPolicy cmi_051695

Anesthesia services reimbursement and coding guidelines

Governs calculation of anesthesia base and time units, applicable modifiers, qualifying circumstances, and related billing rules for professional anesthesia claims across Premera Blue Cross and affiliated lines of business.

Policy Summary

PayerPremera Bluecross

PolicyAnesthesia services reimbursement and coding guidelines

Policy CodePolicy cmi_051695

Change TypeMultiple clarifications and reimbursement modifier updates (material and non-material)

Effective Dateas written

Next Review Date

Key ActionAppend the appropriate anesthesia HCPCS modifier to each anesthesia service (00100-01992, 01999); services submitted without a modifier will be denied.

SourceLink

POLICY UPDATE CHANGES

Policy statement clarified that an E&M service one day preoperatively, on the same day of, or one day postoperatively to an anesthesia service is included in the anesthesia service.

Added guidance in Codes/Coding Guidelines on how to report anesthesia when multiple anesthesia procedures are performed.

Identified that effective November 24, 2024, procedure code 01996 does not require an anesthesia modifier.

Reimbursement for modifier QZ will change from 100% to 85% of the provider's applicable Fee Schedule allowed amount for dates of service on and after March 6, 2026.

Added modifier-specific details from the archived Anesthesia modifier policy into this policy and removed archived Anesthesia Modifier policy from cross reference section.

Descriptions of moderate/conscious sedation were updated to better reflect actual code descriptions.

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

Coverage and Billing Criteria for Anesthesia Services

Anesthesia reimbursement and billing criteria

Rules governing unit calculation, modifier usage, qualifying circumstances, and related E&M and sedation billing.

ALL of the following

ALL of the following
- Total anesthesia minutes are divided by 15 to calculate time units and rounded to the nearest whole hundredth using standard rounding (.5 and above rounds up; .4999 and below rounds down).
- Anesthesia time begins when the anesthesiologist is first in attendance for induction of anesthesia and ends when the patient leaves the operating room or delivery room; recovery room time is included in base units.
ALL of the following
- Standard base units allowed for 01967; labor management: 3 time units for the initial hour and 2 time units for each additional hour.
- To calculate OB anesthesia units: divide the first 60 minutes by 20 and divide remaining minutes by 30, then combine and round per standard methodology.

ALL of the following

An appropriate anesthesia HCPCS modifier must be appended to each anesthesia service code (00100-01992, 01999); services submitted without a modifier will be denied.
ANY of the following
- AA — Anesthesiology services performed personally by an anesthesiologist (do not use when supervising another anesthesiologist).
- AD — Medical supervision by a physician for more than four concurrent anesthesia procedures; physician reimbursement adjusted to 50% of applicable Fee Schedule allowed amount.
- QK — Medical direction of two, three or four concurrent anesthesia procedures; physician reimbursement adjusted to 50% of applicable Fee Schedule allowed amount.
- QX — CRNA service with medical direction by a physician; CRNA reimbursement adjusted to 50% of applicable Fee Schedule allowed amount.

ALL of the following

Physical status modifiers (P1–P6) may be added when warranted to reflect patient complexity per ASA definitions; may allow additional unit values per ASA Relative Value Guide.
Qualifying circumstance codes (99100-99140) may be applied when indicated and documented for difficult or unusual anesthesia conditions, but these codes are identified as Medicare Status B and are not eligible for reimbursement under this policy.

ALL of the following

When the same provider performing the diagnostic or therapeutic service also provides moderate sedation, report 99151, 99152 and add-on 99153 based on 15-minute time increments and patient age.
When a different provider provides moderate sedation, report 99155, 99156 and add-on 99157 based on 15-minute time increments and patient age.
These timed codes require that more than half of the time noted (greater than 8 minutes) be provided and documented in order to report the service; refer to CPT Medicine section table for time guidance.

ALL of the following

Evaluation and management (E&M) services submitted one day preoperatively, on the same date of service, or one day postoperatively are included with any anesthesia procedure assigned a global day period and are considered part of the global anesthesia service.
Pre-anesthesia evaluation by the anesthesiologist for a delayed procedure is integral to the subsequent anesthesia service and not considered separate; a pre-anesthesia evaluation when surgery is canceled may be covered as the level of care rendered (hospital or office visit).
Local anesthesia is integral to the surgical procedure and is not separately reimbursed; nerve blocks are reimbursed based on relative value units and do not require anesthesia time for reimbursement.

ALL of the following

When multiple surgical procedures are performed during a single anesthetic, report only the anesthesia code with the highest base value and combine total anesthesia time for unit calculation.
Effective November 24, 2024, CPT 01996 (daily hospital management of epidural or subarachnoid continuous drug administration) does not require an anesthesia modifier as an exception; provider contracts may supersede this exception.

ALL of the following

Violations of policy (including submitting anesthesia services without required modifiers) may result in increased auditing, contractual penalties, and/or contract termination; disciplinary actions determined by the Plan.

ALL of the following

Rounding: combined units are rounded to the nearest whole hundredth using standard rounding methodology (.5 and above rounds up).

ALL of the following

Key codes related to these criteria include anesthesia procedure codes 00100-01992, 01999; obstetrical anesthesia 01967; moderate/conscious sedation codes 99151-99157; qualifying circumstance add-on codes 99100-99140.

Refer to Coding section for the specific CPT/HCPCS and modifier lists and for fee schedule applicability.

Anesthesia related billing and modifier criteria

Extracted criteria and billing rules from Related Care, Codes/Coding Guidelines, and modifier/reimbursement updates.

ALL of the following

E&M services provided one day preoperatively, on the same day of, or one day postoperatively to an anesthesia service are included in the anesthesia service when the anesthesia procedure is assigned a global period per CMS.

ALL of the following

Effective November 24, 2024, CPT procedure code 01996 does not require an anesthesia modifier; this exception is noted in the policy Exception section and may be subject to contract-specific provisions.

ALL of the following

Modifier QZ reimbursement will change from 100% to 85% of the provider's applicable Fee Schedule allowed amount for dates of service on and after March 6, 2026.

ALL of the following

Codes, Modifiers, and Time Conversion Rules

Anesthesia and related codesCPTCovered

01967	Neuraxial labor analgesia/anesthesia for planned vaginal delivery (this includes repeat subarachnoid needle placement and drug injection and/or any necessary replacement of an epidural catheter during labor)
01996	Daily hospital management of epidural or subarachnoid continuous drug administration (no anesthesia modifier required effective 2024-11-24)
00100-01992,01999	Anesthesia procedure codes requiring provider-level modifiers
99100-99140	Qualifying circumstance codes (add-on codes; list separately in addition to primary anesthesia procedure)
99151-99157	Moderate/conscious sedation codes (initial and additional 15-minute intraservice time add-on codes and reporting scenarios)

Anesthesia modifier exceptionsCPTCovered

01996

Procedure identified as not requiring an anesthesia modifier effective 2024-11-24

ModifiersModifierCovered

QZ	CRNA service: without medical direction by a physician; reimbursement changed to 85% of the provider's applicable Fee Schedule allowed amount for dates of service on or after March 6, 2026
23	Unusual Anesthesia; details added and Modifier 23 policy archived effective April 2, 2026

inv-06: time-to-unit conversion — Standard: total minutes divided by 15; OB anesthesia conversion rules and rounding.

Standard time-to-unit conversionTotal anesthesia minutes divided by 15; result rounded to the nearest whole hundredth (.5 up, .4999 down)

Obstetrical anesthesia conversionFirst 60 minutes divided by 20; remaining minutes divided by 30; then combined and rounded to the nearest whole hundredth

Unit rounding ruleUse standard rounding methodology: .5 unit or more rounded up to next whole unit; .4999 units or less rounded down

inv-07: QZ reimbursement percentage — 85%.

QZ reimbursement percentageReimbursement for modifier QZ will change to 85% of the provider's applicable Fee Schedule allowed amount for dates of service on and after March 6, 2026

Billing Requirements and Provider Responsibilities

Denial Risk

Modifier requirement and denial risk — Anesthesia modifiers required

An appropriate anesthesia HCPCS modifier is required on each anesthesia service (CPT codes 00100–01992, 01999) to identify the level of the provider who rendered the service (for example: CRNA, resident physician, supervising or directing physician anesthesiologist). Reimbursement may be adjusted based on the modifier submitted. Services submitted without an anesthesia modifier may be denied or returned for correction.

Affected codes: 00100–01992, 01999
Submission without modifier may be denied or returned for correction

Billing Rule

Anesthesia reporting and exception (01996)

When multiple anesthesia procedures are performed for the same patient during the same anesthetic episode, report the anesthesia services for each distinct procedure per the Codes/Coding Guidelines. Exception: effective November 24, 2024, CPT procedure code 01996 does not require an anesthesia HCPCS modifier and should be reported without an anesthesia modifier.

Definitions and Operational Notes

inv-10: Anesthesia attendance — Definition of attendance service by an attending anesthesiologist.

Definition of anesthesia attendanceAnesthesia attendance is a service requested by the attending physician where the anesthesiologist documents presence for the entire procedure and provided all usual services (except actual administration of anesthetic agent when applicable) and is medically necessary for the patient's procedure and condition

Attendance time periodAnesthesia time begins when the anesthesiologist is first in attendance for induction and ends when the patient leaves the operating or delivery room; recovery room time is included in base units

inv-11: Physical Status Modifiers — P1-P6 modifiers and their use per ASA Relative Value Guide.

Physical status modifiers listP1, P2, P3, P4, P5, P6

Purpose of P1–P6 modifiersDistinguish levels of complexity of the anesthesia services rendered

Policy Changes and Effective Dates

2024-11-24coding_exception

CPT code 01996 identified as not requiring an anesthesia modifier effective November 24, 2024.

2025-11-04cross_reference_removed

Archived Anesthesia Modifier policy removed from cross-reference section.

2026-03-06reimbursement_change

Reimbursement for modifier QZ changed from 100% to 85% of the provider's applicable Fee Schedule allowed amount for dates of service on and after March 6, 2026.

Policy Summary

PayerPremera Bluecross

PolicyAnesthesia services reimbursement and coding guidelines

Policy CodePolicy cmi_051695

Change TypeMultiple clarifications and reimbursement modifier updates (material and non-material)

Effective Dateas written

Next Review Date

Key ActionAppend the appropriate anesthesia HCPCS modifier to each anesthesia service (00100-01992, 01999); services submitted without a modifier will be denied.

SourceLink

On This Page

inv-12: Related Services (E&M inclusion) — E&M services one day preop, same day, or one day postop are included in the anesthesia service.

E&M inclusion ruleEvaluation and management (E&M) services submitted one day preoperatively, on the same date of service, or one day postoperatively to an anesthesia service are included in the anesthesia service

Pre-anesthesia evaluationA pre-anesthesia evaluation performed when a procedure is delayed remains integral to the subsequent anesthesia and is included

Recovery and local anesthesiaTime spent in the recovery room is included in anesthesia base units; local anesthesia is considered integral to the surgery and not separately reimbursed under the anesthesia service guidance

inv-13: Moderate/Conscious Sedation — Descriptions updated to align with code descriptions.

Alignment with CPT sedation codesModerate/conscious sedation descriptions updated to align with the actual CPT code descriptions for 99151–99157

Same-provider reportingUse CPT 99151–99153 when moderate sedation is provided by the same physician or qualified healthcare professional performing the diagnostic or therapeutic service

Different-provider reportingUse CPT 99155–99157 when moderate sedation is provided by a different physician or qualified healthcare professional than the one performing the procedure