C644 – Specific Re-Assessment - General Thoracic Surgery
OHIP Surgical Procedures Code — General Thoracic Surgery (64) · Schedule of Benefits
A specific re-assessment rendered by a specialist in General Thoracic Surgery (<specialtyCode>64</specialtyCode>). As per , this requires a full, relevant history and physical examination of one or more systems. As a 'C' prefix code, this service is for a non-emergency acute care hospital in-patient and is considered a subsequent visit following the hospital admission assessment (). Subsequent visits are subject to frequency limits based on the duration of hospitalization. As outlined on page , admission assessments may be deemed a specific re-assessment under specific circumstances, such as for 'Z' prefix procedures when the patient was assessed prior to admission for the same illness by the same surgical specialist.
When to Use
- Use C644 for a routine subsequent hospital visit by a Thoracic Surgeon for a patient admitted under their care for a thoracic condition.
- Use C644 when performing a required re-assessment of a patient who remains in hospital beyond the initial post-operative period, provided the visit meets the full history and physical examination requirements.
- Use C644 as the billing code for the initial hospital visit when a patient is transferred to your service from another physician, as the transfer date resets the assessment clock for the new MRP.
Common Pitfalls
- Billing C644 when only a brief progress note is documented; the Schedule of Benefits requires a full, relevant history and physical examination of one or more systems.
- Attempting to bill C644 alongside a special visit premium; you must use the corresponding 'A' prefix assessment code (A644) when claiming special visit premiums for non-elective hospital visits.
- Exceeding the weekly or monthly frequency limits for subsequent visits, which will trigger automatic rejections; use C121 only when an acute intercurrent illness necessitates visits beyond these standard limits.
Billing Tips
- If you are the Most Responsible Physician (MRP) and do not receive hospital-based clinical remuneration, ensure you append the E083 premium to C644 to increase the fee by 30%.
- For patients in the ICU or CCU, remember to add the C101 premium to your C644 claim to capture the additional $9.10 for the specialized setting.
Effective: June 1, 2025
Consultations and Visits
General Thoracic Surgery (64)
Assessment
Hospital and Institutional Consultations and Assessments, Assessments
Full, relevant history and physical examination of one or more systems
Admission assessments are deemed to be a specific re-assessment by a surgical specialist who has assessed the patient prior to admission for the same illness for procedures prefixed with a 'Z' or noted as an IOP.
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