I82.A11

HCC Category Mapping

What This Code Means

A blood clot that suddenly forms in the axillary vein (the main vein in the right armpit area), causing arm swelling and pain.

Coding Tips

• •Verify documentation confirms 'right' axillary vein involvement to distinguish from left or bilateral
• •Confirm acute presentation; chronic axillary thrombosis uses different codes

Clinical Significance

Acute axillary vein thrombosis represents a significant vascular event that can lead to pulmonary embolism, post-thrombotic syndrome, and recurrent venous thromboembolism. This diagnosis is critical for risk adjustment as it reflects active vascular disease requiring anticoagulation therapy, monitoring, and potentially invasive interventions. Accurate capture ensures appropriate resource allocation for ongoing management and complication prevention.

Documentation Requirements

• ✓Provider documentation explicitly stating acute embolism or thrombosis of the axillary vein
• ✓Laterality must be documented (right side) — do not assume from context
• ✓Clinical findings supporting the diagnosis (e.g., swelling, pain, imaging results such as duplex ultrasound or CT venography)
• ✓Current treatment plan including anticoagulation therapy type, duration, and monitoring parameters
• ✓Date of onset or timeframe establishing the acute nature of the condition
• ✓Any precipitating factors (central line placement, surgery, malignancy, hypercoagulable state)

Commonly Confused Codes