Extracorporeal Membrane Oxygenation (ECMO) — CPB 0546 | AETNA Coverage Update

Aetna modified CPB 0546 covering ECMO, effective September 26, 2025. Here's what billing teams need to know before your next claim hits.

Aetna, a CVS Health company, updated its extracorporeal membrane oxygenation coverage policy under CPB 0546 Aetna system. This change affects CPT codes 33946 through 33989 — the full family of ECMO initiation, daily management, cannula insertion, repositioning, and removal codes. If your facility bills for ECMO or cardiothoracic surgery with ECMO support, this update touches your charge capture and medical necessity documentation.

Quick-Reference Table

Aetna ECMO Coverage Criteria and Medical Necessity Requirements 2025

The Aetna ECMO coverage policy under CPB 0546 conditions reimbursement entirely on meeting specific medical necessity criteria. Aetna considers ECMO medically necessary when selection criteria are met. Refer to the complete CPB 0546 policy for the specific clinical criteria — the source data provided does not enumerate them in this excerpt. That's the hinge point for every claim your team submits.

ECMO billing falls into two circuit configurations: veno-venous (VV-ECMO) and veno-arterial (VA-ECMO). CPT 33946 is the base physician ECMO/ECLS code. CPT 33947 covers VA-ECMO initiation. Daily management bills under CPT 33948 (VV) and CPT 33949 (VA). These daily management codes are the ones your revenue cycle team needs to track for long ECMO runs — they bill once per day, every day the patient is on the circuit.

Cannula work has its own code family. Percutaneous peripheral cannula insertion for patients birth through five years bills as CPT 33951. For patients six years and older, it's CPT 33952. Open peripheral insertion follows the same age split: CPT 33953 (birth through five) and CPT 33954 (six and older). Central cannula insertion by sternotomy or thoracotomy uses CPT 33955 for the younger age group and CPT 33956 for older patients.

Medical necessity documentation must match the specific indication Aetna has approved under CPB 0546. Pull the complete policy to confirm the exact clinical criteria before you build your documentation templates. Your physicians' notes need to support whatever indications the policy specifies — vague clinical notes won't hold up at appeal.

Daily ECMO billing under CPT 33948 and 33949 is a per-day charge. As a general RCM best practice — not a requirement stated in CPB 0546 — your team should maintain daily clinical notes supporting continued medical necessity for each day on the circuit. Confirm Aetna's specific documentation requirements directly in the policy.

Coverage Indications at a Glance

Aetna ECMO Billing Guidelines and Action Items 2025

The revised coverage policy is live as of September 26, 2025. Here's what your billing team needs to do now.

1. Audit your charge capture for the full ECMO code family.
Map every procedure your team performs to the correct CPT code from the 33946–33989 range. The age splits and approach (percutaneous vs. open, peripheral vs. central) are where coding errors happen. A central cannula coded as peripheral is a claim denial waiting to happen.

2. Verify age-specific code selection on every pediatric case.
CPT codes 33951, 33953, 33955, 33957, 33959, 33963, 33965, 33969, and 33985 apply to patients birth through five years. The six-and-older codes (33952, 33954, 33956, 33958, 33962, 33964, 33966, 33984, 33986) apply to older patients. Check your CDM and charge capture templates — make sure the age range is part of the selection logic, not just a coding assumption.

3. Pull the complete CPB 0546 policy and confirm specific clinical criteria.
The source data does not enumerate the specific medical necessity criteria for ECMO coverage. Go directly to Aetna's clinical policy bulletin library and pull the full CPB 0546 document. Build your documentation templates from the actual policy language — not summaries.

4. Review daily management billing requirements with your clinical team.
CPT 33948 and 33949 bill daily. As a general RCM best practice, your intensivists and perfusionists should maintain daily clinical notes supporting continued medical necessity for each day on the circuit. Confirm whether Aetna specifies daily documentation requirements in the full CPB 0546 policy before finalizing your billing workflow.

5. Check the related procedure codes for concurrent billing.
Aetna lists lung transplant codes (32851–32854), CABG codes (33510–33536), valve procedures, and structural heart repairs as related CPT codes under CPB 0546. If your facility performs ECMO alongside these procedures, check the applicable coverage policy for each. ECMO billing guidelines don't automatically cover those concurrent procedures — each has its own criteria and reimbursement rules.

6. Flag any cases with left heart vent procedures.
CPT 33988 (insertion) and 33989 (removal) for left heart venting during ECMO are covered but require a thoracic incision — sternotomy or thoracotomy. Document the surgical approach explicitly in the operative note. If the documentation doesn't specify the incision type, expect a denial.

7. Loop in your compliance officer on any cases with complex concurrent billing.
ECMO combined with cardiothoracic surgery (transplant, CABG, valve replacement) creates bundling risk. If your team regularly bills ECMO alongside procedures in the 32851–32854 or 33510–33536 ranges, have your compliance officer review your unbundling logic. This is general billing best practice — not a requirement stated in CPB 0546 — but the financial exposure on these cases justifies the review.

CPT, HCPCS, and ICD-10 Codes for ECMO Under CPB 0546

Covered CPT Codes — ECMO Procedures (When Selection Criteria Are Met)

Key ICD-10-CM Diagnosis Codes

The policy data includes 158 ICD-10-CM codes supporting ECMO medical necessity. The source data provided here reflects a partial set. Pull the full ICD-10 list directly from CPB 0546 on Aetna's clinical policy bulletin library to confirm all applicable diagnosis codes for your charge capture build.