CPT 2026 · Anesthesia

CPT 01991

Global XXX

Anes dx/ther nrv blk&inj oth

Effective 2026-04-01 Conv. factor $33.4009

ASA base units

Payment Methodology

Status Indicator

NCCI Partners

XXX

Global Period

ASA base units

Anesthesia codes are not paid on the Physician Fee Schedule RVU system. Medicare calculates payment as (base units + time units + modifier units) × anesthesia conversion factor. See the CMS Anesthesiologists Center for the current base unit and conversion factor values.

CPT 01991 Billing & Documentation Guide

CPT code 01991 (Anes dx/ther nrv blk&inj oth) is classified under Anesthesia with a global period indicator of XXX. This code uses the ASA base units payment methodology rather than standard RVU-based Physician Fee Schedule pricing. Refer to the methodology notice above for billing implications.

When billing 01991, ensure documentation supports medical necessity and the specific components required for the code's level of service. For E/M codes, document MDM (medical decision-making) elements: problems addressed, data reviewed, and risk. For procedural codes, document the indication, technique, and any complications. Always verify NCCI edits before bundling 01991 with related codes; this code has 10 PTP bundling relationships on file (see table below).

Payment Status & Global Period

CMS Status Indicator

Status not specified

Global Period

XXX

No global period (E/M and other non-procedural services)

NCCI Bundling Edits, CPT 01991

Procedure-to-procedure (PTP) edits. If you bill any of these codes with 01991 on the same date of service, review the modifier indicator and payer policy before submission.

Partner Code	Relationship	Modifier Allowed	Rationale
0178T	Column 1 (primary), can be billed with modifier	Yes	Misuse of Column Two code with Column One code
0179T	Column 1 (primary), can be billed with modifier	Yes	Misuse of Column Two code with Column One code
0180T	Column 1 (primary), can be billed with modifier	Yes	Misuse of Column Two code with Column One code
01992	Column 1 (primary), can be billed with modifier	Yes	Misuse of Column Two code with Column One code
01992	Column 1 (primary), can be billed with modifier	Yes	Mutually exclusive procedures
01995	Column 1 (primary), can be billed with modifier	No	Standard preparation/monitoring services for anesthesia
01996	Column 1 (primary), can be billed with modifier	Yes	Standard preparation/monitoring services for anesthesia
0251T	Column 1 (primary), can be billed with modifier	Yes	Standard preparation/monitoring services for anesthesia
0253T	Column 1 (primary), can be billed with modifier	9	Standard preparation/monitoring services for anesthesia
0282T	Column 1 (primary), can be billed with modifier	Yes	Standard preparation/monitoring services for anesthesia

Frequently Asked Questions, CPT 01991

What does CPT code 01991 mean? +

CPT code 01991 represents: Anes dx/ther nrv blk&inj oth. It's in the Anesthesia category with a global period of XXX.

What is the Medicare reimbursement for CPT 01991? +

What modifiers can I use with CPT 01991? +

Anesthesia codes use a distinct modifier set: AA (personally performed), QK/QY/QX (medical direction variants), QZ (CRNA without medical direction), AD (supervising > 4 rooms), G8/G9 (monitored anesthesia care), and ASA physical status P1-P6. Standard surgical modifiers like 50, 51, 59 do not apply.

What bundling edits apply to CPT 01991? +

This code has 10 NCCI PTP bundling relationships. See the NCCI Bundling section below for full list.