CPT code 45120 represents a major colorectal operation involving removal or bypass of diseased rectum with restoration of intestinal continuity by connecting the colon and anus via both abdominal and perineal approaches. This procedure is clinically significant for management of invasive rectal disease, trauma, or complex benign conditions that require combined access for resection and reconstruction. Nationally, it is a high-acuity inpatient surgical service with implications for operating-room resource use, perioperative care pathways, and postoperative bowel function outcomes.

Key payers in the coverage landscape include Aetna, Blue Cross Blue Shield, Cigna, UnitedHealthcare, and Medicare. Readers will find a concise clinical and billing description of the procedure, typical site-of-service information, and the context needed for claims processing and coding accuracy. The publication outlines benchmarks and policy-relevant considerations such as inpatient surgical classification, resource intensity, and clinical indications that impact utilization and payment. It also highlights areas where payers commonly apply coverage criteria and prior authorization for complex colorectal surgeries.

This national overview is intended for coding professionals, clinicians involved in colorectal surgery, and payers seeking clarity on procedural definition and typical delivery setting. Data not available in the input: detailed payer-specific reimbursement rates, ICD-10 diagnosis pairings, and associated taxonomies.