CPT® Code 94720

Deleted

1. Indications

The Carbon Monoxide Diffusing Capacity test is indicated for various clinical scenarios where assessment of lung function is necessary. The following conditions may warrant the performance of this test:

• Chronic Obstructive Pulmonary Disease (COPD) - To evaluate the extent of lung impairment and monitor disease progression.
• Interstitial Lung Disease - To assess the impact of lung tissue scarring on gas exchange capabilities.
• Emphysema - To determine the degree of alveolar damage and its effect on diffusing capacity.
• Pulmonary Fibrosis - To evaluate the severity of lung function impairment due to fibrotic changes.
• Preoperative Assessment - To assess lung function prior to surgical procedures, especially in patients with known respiratory issues.

2. Procedure

The procedure for conducting the Carbon Monoxide Diffusing Capacity test involves several key steps to ensure accurate measurement of lung function. The following outlines the procedural steps:

• Step 1: Patient Preparation - The patient is instructed to avoid smoking and certain medications that may affect lung function for a specified period before the test. This preparation is crucial to obtain reliable results.
• Step 2: Baseline Measurements - Initial lung function measurements may be taken to establish a baseline. This can include spirometry to assess overall lung capacity and function.
• Step 3: Inhalation of Test Gas - The patient is then asked to inhale a gas mixture that contains a known concentration of carbon monoxide. This inhalation is typically done in a controlled environment to ensure safety and accuracy.
• Step 4: Breath Hold - After inhalation, the patient holds their breath for a specified duration, allowing the carbon monoxide to diffuse across the alveolar-capillary membrane into the bloodstream.
• Step 5: Exhalation and Measurement - The patient then exhales into a collection device, and the concentration of carbon monoxide in the exhaled air is measured. This measurement is compared to the initial concentration inhaled to determine the diffusing capacity.

3. Post-Procedure

After the Carbon Monoxide Diffusing Capacity test, the patient may be monitored briefly to ensure there are no immediate adverse reactions, particularly since carbon monoxide is a toxic gas. Patients are typically advised to resume normal activities unless otherwise directed by their healthcare provider. Results from the test are analyzed and interpreted by a qualified healthcare professional, who will discuss the findings with the patient and determine any necessary follow-up actions or treatments based on the results.