ModifiedPremera BluecrossPolicy cmi_051695

Anesthesia reimbursement and coding guidelines

Defines how the Plan calculates anesthesia base and time units, applicable modifiers, related services and billing rules for professional anesthesia claims across Premera Blue Cross and affiliated lines of business.

Policy Summary

PayerPremera Bluecross

PolicyAnesthesia reimbursement and coding guidelines

Policy CodePolicy cmi_051695

Change TypeModifier reimbursement and coding clarifications

Effective Date

Next Review Date

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

SourceLink

POLICY UPDATE CHANGES

Effective November 24, 2024, procedure code 01996 does not require an anesthesia modifier.

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

Policy statement now indicates 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 on how to report anesthesia when multiple anesthesia procedures are performed.

Archived Anesthesia Modifier policy removed from cross-reference section.

00100-01992,01999Anesthesia codes referenced

99100-99140Qualifying add-ons (not reimbursed)

3 / 2OB epidural time units

100%->85%

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.

QZ reimbursement change

01996Modifier exception

Anesthesia Coverage Criteria

Anesthesia coverage criteria

General coverage and billing criteria for anesthesia professional services:

Anesthesia time units begin when the anesthesiologist first attends the patient for induction of anesthesia and end when the patient leaves the operating room or delivery room; time spent in the recovery room is included in anesthesia base units.

ALL of the following

The service is requested by the attending physician.
The anesthesiologist documents presence for the entire procedure and provided all usual services except actual administration of anesthetic agent.
The anesthesia attendance is medically necessary for the patient's surgical procedure and condition.

ALL of the following

General calculation: total anesthesia minutes divided by 15; rounding to the nearest whole unit with .5 and above rounded up and .4999 and below rounded down.
For obstetrical (OB) anesthesia, special time unit calculations and base units apply as described in coding guidance (see policy coding section).

An appropriate anesthesia HCPCS modifier must be appended to each anesthesia service code (CPT/HCPCS range 00100-01992, 01999) to identify the provider level; services submitted without a modifier will be denied and reimbursement may be adjusted based on the modifier submitted.

Qualifying circumstance add-on codes (e.g., 99100-99140) are identified as Medicare Status B and are not eligible for reimbursement under this policy.

ALL of the following

Evaluation and management (E&M) services submitted one day preoperatively, on the same date of service, or one day postoperatively for an anesthesia procedure assigned a global day period of 'XXX' are included in the anesthesia service and are not separately reimbursed.
A pre-anesthesia evaluation by the anesthesiologist when the procedure is delayed is integral to and considered part of the subsequent anesthesia service (not a separate procedure).
A pre-anesthesia evaluation when surgery is canceled may be covered as a hospital or office visit at the level of care rendered.

When multiple surgical procedures are performed under a single anesthetic, report only the anesthesia code with the highest base units and combine the total anesthesia time for unit calculation; failure to follow reporting guidance may prompt audit or contract penalties.

Exception: procedure code 01996 does not require an anesthesia modifier effective November 24, 2024.

Anesthesia billing and reimbursement criteria

Policy clarifications and billing rules relevant to anesthesia services, modifiers, and related E&M services.

E&M inclusion: An evaluation and management (E&M) service one day preoperatively, on the same day of service, or one day postoperatively to an anesthesia service assigned a global day period of 'XXX' is included in the anesthesia service and is not separately reimbursed.

ALL of the following

Procedure code 01996 does not require an anesthesia modifier effective November 24, 2024.

ALL of the following

Effective dates of service on and after March 6, 2026, reimbursement for modifier QZ (CRNA service without medical direction by a physician) will be 85% of the provider's applicable Fee Schedule allowed amount (reduction from prior 100%).

Reporting multiple anesthesia procedures: Guidance has been added on how to report anesthesia when multiple anesthesia procedures are performed — report the anesthesia code with the highest base value and combine total anesthesia time for unit calculation.

Codes, Modifiers, and Time Calculations

Anesthesia related codes and add-onsCPTCovered

99151-99157	Moderate (conscious) sedation codes — distinctions for performing vs supportive provider and age; time-based increments
99100-99140	Qualifying circumstances (add-on) codes; noted as Medicare Status B and not eligible for reimbursement
01967	Obstetrical delivery epidural anesthesia (OB anesthesia) — standard base units; special time-unit calculation

Qualifying circumstances (add-on) detailsCPTCovered

+99100	Anesthesia for patient of extreme age (younger than 1 year and older than 70) - add-on
+99116	Anesthesia complicated by utilization of total body hypothermia - add-on
+99135	Anesthesia complicated by utilization of controlled hypotension - add-on
+99140	Anesthesia complicated by emergency conditions - add-on
+99153	Moderate sedation each additional 15 minutes - add-on
+99157	Moderate sedation each additional 15 minutes by provider other than performing clinician - add-on

Modifiers with reimbursement impactModifierCovered

QZ	CRNA service: without medical direction by a physician — informational; reimbursement changing to 85% effective 2026-03-06
AA	Anesthesiology services performed personally by an anesthesiologist — informational; reimbursement not affected
AD	Medical supervision by a physician: more than four concurrent anesthesia procedures — physician reimbursement adjusted to 50%
QK	Medical direction of two, three or four concurrent anesthesia procedures involving qualified individuals — physician reimbursement adjusted to 50%
QX	CRNA service: with medical direction by a physician — CRNA reimbursement adjusted to 50%
QY	Medical direction of one CRNA by an anesthesiologist — physician reimbursement adjusted to 50%

Anesthesia modifier exceptionsCPTCovered

01996

Procedure code identified as not requiring an anesthesia modifier effective November 24, 2024

Anesthesia time unit calculation — standard and OB-specific rules

Standard time unit calculationTotal anesthesia minutes divided by 15; result rounded to nearest whole unit (.5 and above round up; .4999 and below round down)

OB (obstetrical) time unit calculationFirst 60 anesthesia minutes divided by 20; remaining minutes divided by 30; units then combined and rounded to the nearest whole unit

Time basis usedAnesthesia time-based reimbursements are calculated on a four-unit hour basis (i.e., 15-minute units)

Inclusion of recovery timeTime spent in the recovery room is included in anesthesia base units and not separately reimbursed

QZ reimbursement percentage

Billing Actions and Provider Requirements

Billing Rule

Modifier requirement and reimbursement adjustments

An appropriate anesthesia HCPCS modifier is required on each anesthesia service code (00100-01992, 01999) to identify the provider level. Anesthesia services submitted without a modifier will be denied. Reimbursement may be adjusted based on the modifier submitted.

Anesthesia modifier required on each anesthesia service (00100-01992, 01999).
Services submitted without an anesthesia modifier will be denied reimbursement.
Reimbursement may be adjusted based on the specific modifier submitted.

Billing Rule

Increased service billing guidance

For increased anesthesia service, bill additional time units rather than using modifier 22; physical status modifiers may be used to indicate that additional work was required.

Definitions and Related Service Notes

ASA physical status (P1–P6) and relation to additional unit values

ASA Physical Status categoriesP1 — normal healthy person; P2 — mild systemic disease; P3 — severe systemic disease; P4 — severe systemic disease that is a constant threat to life; P5 — moribund patient not expected to survive without the operation; P6 — declared brain-dead organ donor

PurposeUsed to indicate patient complexity and distinguish levels of anesthesia service complexity

Additional unitsAdditional unit values may be allowed for some physical status modifiers as recommended by the ASA Relative Value Guide

HCPCS anesthesia modifiers and reimbursement impact

Modifiers listedAA, AD, QK, QX, QY, QZ — appended to anesthesia codes to identify the provider who rendered the service

Modifier function

Policy Summary

PayerPremera Bluecross

PolicyAnesthesia reimbursement and coding guidelines

Policy CodePolicy cmi_051695

Change TypeModifier reimbursement and coding clarifications

Effective Date

Next Review Date

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

SourceLink

On This Page

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

Prior reimbursement levelModifier QZ reimbursement was previously 100% of the provider's applicable Fee Schedule allowed amount

Effective dateMarch 6, 2026 (applies to dates of service on and after this date)

Bill additional time units for increased anesthesia services instead of modifier 22.
Physical status modifiers may be used to identify additional work.

Note

Anesthesia modifier exception for 01996

Procedure code 01996 is an exception and does not require an anesthesia modifier effective November 24, 2024.

01996 does not require an anesthesia modifier effective 2024-11-24.

Billing Rule

Modifier QZ reimbursement change

Effective dates of service on and after March 6, 2026, reimbursement for services billed with modifier QZ will change from 100% to 85% of the provider's applicable Fee Schedule allowed amount. QZ is an informational modifier appended to CRNA services to indicate no supervision by an anesthesiologist.

Modifier QZ: CRNA service without medical direction by a physician (informational).
Reimbursement change for QZ effective 2026-03-06: 100% -> 85% of applicable Fee Schedule allowed amount.

Identify provider level (e.g., anesthesiologist personal service, medical supervision, CRNA with/without medical direction) and may adjust reimbursement

RequirementAn appropriate anesthesia HCPCS modifier is required on each anesthesia service code (00100–01992, 01999); services submitted without a modifier will be denied

Related Services — E&M inclusion

E&M inclusion timingAn E&M service performed one day preoperatively, on the same day, or one day postoperatively to an anesthesia service is included in the anesthesia service and not separately reimbursed

Pre-anesthesia evaluationWhen a pre-anesthesia evaluation is delayed and integral to the subsequent anesthesia service, it is included in the anesthesia service

Canceled surgery evaluationA pre-anesthesia evaluation for a canceled surgery may be covered separately as an office or hospital visit where applicable

Multiple anesthesia procedures — reporting guidance

Primary reporting ruleWhen multiple surgical procedures are performed under a single anesthetic, report only the anesthesia code with the highest base unit value and combine total anesthesia time for unit calculation

Time aggregationTotal anesthesia minutes for the entire anesthetic are used to calculate time-based units (per standard division rules) when multiple procedures occur

Audit/penalty noteIncorrect reporting of multiple anesthesia procedures may lead to audits or contractual penalties