CPT code 33956 identifies the open insertion of a central cannula via sternotomy or thoracotomy in children aged six years and older to establish extracorporeal circulation. This code covers a high-acuity cardiothoracic surgical procedure that enables cardiopulmonary bypass or extracorporeal life support during complex cardiac operations. Nationally, accurate coding for this procedure is important for clinical documentation, surgical case grouping, and appropriate payment for pediatric cardiac surgery.

Key payers referenced in this analysis include Aetna, Blue Cross Blue Shield, Cigna, UnitedHealthcare, and Medicare. The publication provides a concise review of the clinical context for CPT code 33956, outlines typical sites of service and procedural indications, and summarizes commonly applied modifiers where available. Readers will find benchmarks for coding practice, notes on clinical documentation elements that support appropriate use of the code, and a summary of policy considerations affecting coverage and billing for high-acuity pediatric cardiothoracic procedures. Data not available in the input is noted where applicable.