Billing code 33956: ECMO cannula insertionMedicare rate & RVUs in Guam
Reports placement of central cannulae for extracorporeal support in a patient younger than five, rather than peripheral access or ECMO initiation.
CMS doesn’t publish an office rate for 33956 in Guam.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 9 sections
What 33956 covers
This service covers placing cannulae in central vessels or the heart to establish access for extracorporeal membrane oxygenation or extracorporeal life support in a patient younger than five. It is typically performed by a cardiac surgeon or another surgeon experienced in ECMO cannulation, often in an operating room or intensive care setting when severe cardiac or respiratory failure requires extracorporeal support. The code represents cannula insertion, not the separate work of initiating or managing ECMO/ECLS.
Select the code based on the patient’s age and central rather than peripheral cannula placement. The operative or procedure note should identify the central access site, cannulae placed, and the patient’s age. CMS assigns a 0-day global period, so same-day preoperative and postoperative care is included. When multiple procedures are performed in one session, the highest-valued procedure is paid in full and other procedures are subject to the standard 50% reduction. Modifier 50 is inappropriate. Assistant-at-surgery payment requires medical-necessity documentation; co-surgeon and team-surgery payment require supporting documentation.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
33956 in Hawaii, Guam
| Payment locality | Office | Facility |
|---|---|---|
| Hawaii, Guam | Unavailable | $718.33 |
How the 33956 rate is calculated
Each of 33956’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 33956
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 15.60Practice expense 3.28Malpractice 3.76
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 33956
The CMS indicators that decide how 33956 is paid alongside other services.
CMS payment indicators · 33956
ECMO cannula insertion
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 000 | Same-day global: pre- and post-op care on the day of the procedure is included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 0 | Not paid without supporting documentation. |
| Co-surgeons (62) | 1 | Permitted with supporting documentation. |
| Team surgery (66) | 1 | Permitted with supporting documentation. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
33956 without 51 · national facility
$756.20
ECMO cannula insertion
33956-51 · Second procedure: 50%
$378.10
When this isn’t the highest-valued procedure in the session, Medicare pays 50% of its fee schedule amount (the highest is paid at 100%).
33956 compared with similar codes
Compare codes
33956 vs 33955 vs 33952 vs 33954 vs 33946: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 33955Central cannulation
- Use 33956 for central cannula insertion in a patient younger than five; use 33955 for a patient age five or older.
- 33952ECMO cannulation
- 33952 describes peripheral percutaneous cannula insertion in a younger patient. This code is for central cannula insertion.
- 33954ECMO cannulation
- 33954 describes peripheral open cannula insertion in a younger patient. Choose this code when the cannulae are placed centrally.
- 33946ECMO initiation
- 33946 reports initiation of venovenous ECMO/ECLS; this code reports placement of central cannulae in a younger patient.
33956 billing questions
How is this code distinguished from 33955?
Both describe central cannula insertion for ECMO/ECLS. This code is for patients younger than five; 33955 is for patients age five and older.
When should a peripheral cannula insertion code be used instead?
Use the applicable peripheral insertion code when the cannulae are placed through peripheral rather than central access. The peripheral code also depends on the patient’s age and insertion approach.
Does this code report ECMO initiation?
No. It reports central cannula insertion. ECMO/ECLS initiation is a separate service when performed and documented.
What documentation supports reporting this code?
Document the patient’s age, central access site, cannulae placed, and the procedure performed. The record should distinguish central cannulation from peripheral access.
How does the 0-day global period affect same-day care?
Same-day preoperative and postoperative care is included in the procedure’s global period.
Can an assistant or additional surgeon be reported?
Assistant-at-surgery payment requires documentation of medical necessity. Co-surgeon and team-surgery payment require supporting documentation.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
Fee sheets
Put 33956 and the rest of your codes on one sheet
Build a fee sheet from your own code list at your locality, put your payer contracts beside Medicare, and see what changed each quarter.
Build my fee sheetOr price your code list free →