All codes
Z820
Z820 – Insertion of intracranial pressure monitor and/or external ventricular drainage
OHIP Psychiatric Code — NEUROLOGICAL SURGICAL PROCEDURES · Schedule of Benefits
Insertion of intracranial pressure monitor and/or external ventricular drainage. The fee for anaesthesia (Z820C) is calculated with 7 base units plus time units. The service of a surgical assistant is not eligible for payment.
When to Use
- Use Z820 for the bedside or operating room insertion of an external ventricular drain (EVD) for acute hydrocephalus or intracranial pressure monitoring.
- Select Z820 when performing a burr hole specifically for the purpose of placing a pressure monitoring device or drainage catheter, distinct from a formal craniotomy.
Common Pitfalls
- Attempting to bill a surgical assistant fee (suffix B) will result in an automatic rejection, as this procedure is explicitly non-eligible for assistant payment.
- Billing Z820 alongside a formal craniotomy (e.g., Z825) for the same site may be flagged as unbundling; ensure the EVD placement is a distinct clinical necessity if billed separately.
- Failure to document the specific Injury Severity Score (ISS) in the medical record when claiming the E420 trauma premium will lead to recovery of the 50% premium during audit.
Billing Tips
- Always verify the start time of the procedure to determine if E409 or E410 applies, as these premiums significantly increase the base fee for non-elective, after-hours cases.
- If the patient is under 16 years of age, ensure the applicable age premium (e.g., 10% to 30%) is applied to the claim to maximize the procedural reimbursement.
Ready to bill this code?
SnapBill makes OHIP billing simple — auto-filled codes, validation, and batch submission.