CPT code 36516 denotes therapeutic apheresis involving extracorporeal treatment of blood to remove immune complexes or selectively filter blood components with return of plasma to the patient. This procedure is clinically important for conditions requiring removal of pathogenic plasma constituents and is performed using specialized apheresis equipment in outpatient or hospital-based settings. Nationally, accurate coding of this service affects clinical documentation, utilization tracking, and payer coverage decisions for high-cost, resource-intensive therapies.

Key payers in scope include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the clinical service represented by the code, typical sites of service, and which major payers are relevant to coverage and payment discussions. The publication also summarizes common modifiers and administrative considerations when billing for extracorporeal therapeutic apheresis, and provides context for benchmarking and policy review. The report is intended to inform coding, billing, and policy stakeholders about how CPT code 36516 is used in clinical practice and payer settings across the United States.