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A4651 Calibrated microcap tube

A Codes

Also known as: microcap, capillary tube, collection tube

A calibrated glass tube of precisely measured small diameter used for collecting, measuring, and analyzing blood samples. Used in hematology and chemistry testing.

In Plain Language

tiny glass tube for blood testing; capillary collection tube

Clinical Context

Used for collecting small blood samples, particularly in pediatric patients or for point-of-care testing. Calibrated tubes allow accurate volume measurement.

RVU Information

CPT A4651 does not have a physician work RVU assigned by CMS. This is typical for supply, drug, and equipment codes — reimbursement is based on Average Sales Price (ASP), fee schedules, or payer contracts rather than the RVU system.

Billing & Documentation

HCPCS A-codes cover medical supplies, equipment, and transport services. Documentation must establish medical necessity and include a physician order. For durable medical equipment (DME), a Certificate of Medical Necessity (CMN) or detailed written order may be required.

Specialties

Laboratory MedicinePediatricsPrimary Care

Frequently Asked Questions

What is CPT code A4651?

CPT A4651 (Calibrated microcap tube) is a A Codes code. A calibrated glass tube of precisely measured small diameter used for collecting, measuring, and analyzing blood samples. Used in hematology and chemistry testing.

Does Medicare cover A4651?

Medicare coverage for A4651 depends on medical necessity and applicable Local Coverage Determinations (LCDs). Used for collecting small blood samples, particularly in pediatric patients or for point-of-care testing. Calibrated tubes allow accurate volume measurement. A physician order is typically required.

When is CPT A4651 used?

Used for collecting small blood samples, particularly in pediatric patients or for point-of-care testing. Calibrated tubes allow accurate volume measurement.

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CPT® is a registered trademark of the American Medical Association. Data sourced from CMS Physician Fee Schedule RVU26A. Descriptions, synonyms, and clinical context are original content by RVU Edge.