M137 – Thoracotomy with or without biopsy
OHIP Ophthalmology Code — RESPIRATORY SURGICAL PROCEDURES · Schedule of Benefits
Thoracotomy with or without biopsy is an operative procedure involving a surgical incision into the pleural space. It is performed for exploratory purposes and may include obtaining a tissue sample (biopsy) for diagnostic examination. This procedure is listed under both the Respiratory Surgical Procedures (:643) and the Cardiovascular Surgical Procedures (:651) sections of the Schedule of Benefits. The fee for this service includes standard pre-operative and post-operative care as defined in the Surgical Preamble (:529). - The anaesthesia fee (M137C) is calculated based on 13 base units plus time units. - The surgical assistant fee (M137B) is calculated based on 9 base units plus time units.
When to Use
- Use M137 for an open exploratory thoracotomy where the primary intent is to enter the pleural space for diagnosis or biopsy, rather than a specific therapeutic resection.
- Select M137 when performing an open pleural biopsy via thoracotomy, as it is the designated code for this specific surgical access and tissue sampling approach.
Common Pitfalls
- Do not bill M137 in conjunction with more specific thoracic procedures (e.g., lobectomy or wedge resection) if the thoracotomy is simply the surgical approach for those procedures; the thoracotomy is considered inclusive.
- Avoid billing M137 if the procedure was performed via VATS (Video-Assisted Thoracoscopic Surgery), as M137 is specific to open thoracotomy and requires a different code set for endoscopic approaches.
- Failure to document the Injury Severity Score (ISS) in the medical record will result in the rejection of the E420 trauma premium, even if the procedure meets the clinical criteria for trauma.
Billing Tips
- When performing multiple procedures during the same operative session, ensure the major procedure is billed at 100% and subsequent procedures are reduced by 15% per the multiple procedure rule, unless they are for distinct, unrelated conditions.
- If you are the primary surgeon, do not claim the assistant's fee (M137B) for yourself; ensure the surgical assistant bills their own code separately to avoid claim duplication errors.
Effective: April 1, 2025
P. Respiratory Surgical Procedures
RESPIRATORY SURGICAL PROCEDURES
Surgical
Respiratory Surgical Procedures, Cardiovascular Surgical Procedures
Anaesthesia basic units: 13. Assistant basic units: 9. Unit fees are specified in the General Preamble (:99,:106).
This procedure is listed in both the Respiratory Surgical Procedures section (:643) and the Cardiovascular Surgical Procedures section (:651).
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