Summary & Overview
CPT 00566: Anesthesia for Direct CABG Without Pump Oxygenator
CPT 00566 represents anesthesia services for direct coronary artery bypass grafting performed without a pump oxygenator (off-pump CABG). Nationally, this code matters because it identifies specialized intraoperative anesthetic management for high-acuity cardiac surgery cases and supports appropriate classification for hospital billing and resource tracking. Major commercial payers included in this discussion are Aetna, Blue Cross Blue Shield, Cigna Health, and UnitedHealthcare.
Readers will find a concise overview of the clinical context for CPT 00566, how it aligns with related surgical codes for coronary artery bypass, and common billing modifiers and documentation elements that typically accompany anesthesiology services for CABG. The publication outlines payer coverage considerations, coding relationships to on- and off-pump CABG procedures, and relevant ICD-10 diagnostic pairings used to support medical necessity. Benchmarks and policy updates relevant to anesthesiology coding for cardiac surgery are summarized alongside typical site-of-service implications for inpatient OR cases. Data not available in the input is clearly noted where applicable.
CPT Code Overview
CPT 00566 describes anesthesia for direct coronary artery bypass grafting; without pump oxygenator. This procedure is an anesthesiology service typically provided in the inpatient hospital operating room (OR) setting. The code captures anesthesia care during coronary artery bypass grafting performed on the beating heart or otherwise without use of a cardiopulmonary bypass pump/oxygenator.
Clinical & Coding Specifications
Clinical Context
A 64-year-old patient with multi-vessel atherosclerotic coronary artery disease presents for elective direct coronary artery bypass grafting (CABG) without use of a cardiopulmonary bypass pump (off-pump CABG). Preoperative evaluation documents symptoms of angina and recent noninvasive testing showing significant native coronary stenoses. The patient is admitted to the inpatient operating room suite. The anesthesiology team performs a preoperative assessment, establishes invasive monitoring (arterial line, central venous access as indicated), administers general endotracheal anesthesia, and manages hemodynamics throughout sternotomy, coronary graft harvest and anastomosis on the beating heart. Postoperatively the patient is transferred to the cardiothoracic intensive care unit for continued anesthetic emergence, ventilatory support as needed, and hemodynamic stabilization. Documentation includes start and stop times for anesthesia, monitoring modalities used, airway management, intraoperative events, and medications administered.
Coding Specifications
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Common Modifiers
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QS- Monitored anesthesia care service- Use when the anesthesia service provided is monitored anesthesia care rather than general anesthesia for the procedure.
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QX- CRNA service with medical direction by a physician- Use when a certified registered nurse anesthetist (CRNA) furnishes the anesthesia and a physician provides medical direction meeting CMS or payer criteria.
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Provider Taxonomies
| Taxonomy Code | Specialty |
|---|---|
207L00000X | Anesthesiology Physician |
- The
207L00000Xtaxonomy represents physicians specialized in anesthesiology who provide perioperative anesthesia care, airway management, and intraoperative physiologic support for cardiothoracic surgery.
Related Diagnoses
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I25.10- Atherosclerotic heart disease of native coronary artery without angina pectoris- Clinical relevance: Indicates underlying coronary atherosclerosis that may require revascularization with direct CABG; can be an indication for the anesthesia service reported with
00566.
- Clinical relevance: Indicates underlying coronary atherosclerosis that may require revascularization with direct CABG; can be an indication for the anesthesia service reported with
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I25.110- Atherosclerotic heart disease of native coronary artery with unstable angina pectoris- Clinical relevance: Represents unstable ischemic symptoms prompting urgent or semi-urgent CABG; anesthesia management for off-pump CABG is reported with
00566.
- Clinical relevance: Represents unstable ischemic symptoms prompting urgent or semi-urgent CABG; anesthesia management for off-pump CABG is reported with
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I25.119- Atherosclerotic heart disease of native coronary artery with unspecified angina pectoris- Clinical relevance: Documents symptomatic coronary disease where CABG may be performed; supports medical necessity for anesthesia described by
00566.
- Clinical relevance: Documents symptomatic coronary disease where CABG may be performed; supports medical necessity for anesthesia described by
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I20.9- Angina pectoris, unspecified- Clinical relevance: Symptom-level diagnosis often present in patients undergoing CABG; correlates with the need for revascularization and associated anesthetic care.
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I21.9- Acute myocardial infarction, unspecified- Clinical relevance: Represents recent myocardial infarction which can be an indication for urgent CABG in select cases; anesthesia services for off-pump CABG are reported with
00566when applicable.
- Clinical relevance: Represents recent myocardial infarction which can be an indication for urgent CABG in select cases; anesthesia services for off-pump CABG are reported with
Related CPT Codes
| CPT Code | Description | Relationship to 00566 |
|---|---|---|
00567 | Anesthesia for direct coronary artery bypass grafting; with pump oxygenator | Alternate technique: 00567 applies when cardiopulmonary bypass with pump oxygenator is used instead of off-pump CABG; mutually exclusive depending on surgical technique. |
| 33510 | Coronary artery bypass, vein only; single coronary venous graft | Surgical companion: a common standalone graft procedure that may be one of the targets during CABG for which 00566 provides anesthesia care.
| 33511 | Coronary artery bypass, vein only; 2 coronary venous grafts | Surgical companion: two-vessel vein grafting often performed during CABG procedures requiring anesthesia reported with 00566.
| 33512 | Coronary artery bypass, vein only; 3 coronary venous grafts | Surgical companion: three-vessel vein grafting commonly performed in multivessel disease; anesthesia for this surgery is reported with 00566.
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Usage Notes
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The listed surgical CPT codes (
33510,33511,33512) represent specific bypass graft counts that may be performed during the same operative episode for which00566documents the anesthesia service. -
00567is used as an alternative anesthesia code when cardiopulmonary bypass with pump oxygenator is used instead of the off-pump technique described by00566.
National Reimbursement Benchmarks
National mean commercial rates for CPT 00566 vary substantially compared with Medicare and the BUCA average. BUCA’s mean allowed rate of $475.71 sits below larger commercial payers such as Blue Cross Blue Shield ($1,190.96) and Cigna ($1,318.69), while Medicare-level data is not provided in the input and therefore is not represented numerically here.
Dispersion measured by the inter-percentile spread (P75 minus P25) is widest for Cigna ($2,061.50) and Aetna ($1,349.44), indicating broader variability in allowed rates. The tightest distributions are seen with UnitedHealth Group (UHC) with a spread of $25.47 and BUCA with a spread of $761.38. The table and chart below present the full breakdown.
State Benchmarks
State: AK1 / 50
Alaska Benchmarks
Alaska exhibits a wide spread in reimbursement rates for CPT code 00566, with Blue Cross Blue Shield showing the largest range between the 25th and 75th percentiles ($1,237.50 to $1,821.60), a difference of $584.10. In contrast, Aetna, Cigna, and UnitedHealth Group display minimal rate variation, with their 25th, 50th, and 75th percentiles clustered closely together. This suggests that some payers maintain fixed or narrowly negotiated rates, while others allow for substantial variability.
Compared to national averages, Alaska's mean rates for Blue Cross Blue Shield and BUCA are significantly higher, while UnitedHealth Group and Cigna remain below or near national benchmarks. The table and chart below present the full breakdown of payer-specific rates in Alaska, highlighting these regional differences.
Key Insights for Alaska
- Blue Cross Blue Shield is the highest paying payer for CPT 00566 in Alaska, with a mean rate of $1,553.60.
- UnitedHealth Group offers the lowest mean rate at $75.12, significantly below both state and national averages.
- Alaska's mean rates for most payers, especially Blue Cross Blue Shield and BUCA, are notably higher than national benchmarks, indicating a substantial regional premium.
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