CPT Code 00813: Anesthesia for Combined Upper and Lower Intestinal Endoscopic Procedures, Deep Sedation/General Anesthesia

What is CPT code 00813?

CPT code 00813 describes the administration of anesthesia services for combined upper and lower intestinal endoscopic procedures, such as screening colonoscopy or diagnostic colonoscopy, when deep sedation or general anesthesia is required. This procedure involves GI anesthesia care, where an endoscope is introduced distally into the abdomen, often to evaluate or treat conditions such as inflammatory bowel disease or volume depletion.

This code is typically used when the patient presents high-risk factors, including advanced or severe cardiopulmonary disease, or when multiple procedures are performed during the same session. Accurate use of CPT 00813 ensures proper reimbursement through the Medicare physician fee schedule and commercial payers. Providers must justify the medical necessity in the medical record, particularly when using procedures for relatively healthy individuals undergoing routine care.

When reporting CPT code 00813, healthcare providers should follow proper anesthesia modifiers, document all aspects of the anesthesia procedure and procedural intervention, and align their reporting with anesthesia codes and billing guidelines to avoid claim issues. This is essential for accurate billing and to meet requirements for medicaid services and other payers.

Documentation requirements

For CPT 00813, the anesthetic record must include comprehensive details to ensure accurate billing and compliance with the Medicare physician fee schedule and the commercial payers' guidelines. These documentation elements support the medical necessity of deep sedation or general anesthesia for intestinal endoscopic procedures such as a screening colonoscopy or diagnostic colonoscopy.

Required documentation includes:

• Indications for deep sedation or general anesthesia, such as ASA III+, advanced cardiopulmonary disease, severe cardiopulmonary disease, volume depletion, or pediatric age
• Pre-anesthetic assessment including medical history, airway evaluation, and risk stratification (e.g., for healthy individuals or those at high risk)
• Start and stop times of the anesthesia care, including base units and anesthesia services provided
• Monitoring records (e.g., vital signs) and medications administered during the procedure
• Recovery status, including the patient's responsiveness, discharge criteria, and any additional monitoring required
• Linkage to the primary procedure code (e.g., 45378 for colonoscopy or 45385 for polypectomy), with clinical justification for the anesthesia procedure and complexity
• Documentation of anesthesia modifiers when applicable (e.g., PT, QS), particularly if multiple procedures or same-day upper and lower GI procedures are performed

Proper documentation requirements are essential when billing for markedly invasive surgical procedures, especially for anesthesia codes that Medicaid services or other payers may review. The medical record should link the procedure performed and the anesthesia services rendered to the patient’s condition and clinical decision-making process.

Billing guidelines

The following information is important to remember when billing CPT code 00813.

• Base units: 5 base units are assigned to CPT code 00813.
• Billable time: Add actual anesthesia time in 15-minute units (also called time units) to the base units to calculate total billable units.
• Modifiers required: Report appropriate provider-specific anesthesia modifiers, such as: -AA: Anesthesia services personally performed by an anesthesiologist; -QX: CRNA with medical direction by a physician; -QZ: CRNA without medical direction
• Physical status modifiers (P1–P6): Use to reflect patient risk (e.g., P3 for patients with severe cardiopulmonary disease).
• Not for moderate sedation: Do not report CPT 00813 for moderate sedation or uncomplicated colonoscopies—use CPT 00812 (anesthesia for colonoscopy) or CPT 00811 (screening colonoscopy) instead.
• Medical necessity required: Thorough documentation must justify deep sedation or general anesthesia, especially for low-risk or healthy individuals.
• Risk of denials: Many payers, including Medicare and Medicaid, may deny reimbursement if the medical record lacks sufficient support for elevated complexity (e.g., no history of inflammatory bowel disease, advanced cardiopulmonary disease, or other relevant risk factors).

Other relevant CPT codes

• 00811: High-complexity colonoscopy anesthesia
• 99152–99153: Moderate sedation codes