1. What is Lung Diffusion Capacity?

Lung diffusion capacity (DL) measures how well oxygen passes from the lungs to the bloodstream. It's an important indicator of lung function and gas exchange efficiency.

2. How Does the Calculator Work?

The calculator uses the lung diffusion equation:

Where:

• \( V \) — Volume of gas transferred (L)
• \( \Delta P \) — Pressure difference across the membrane (mmHg)
• \( DL \) — Lung diffusion capacity (mL/min/mmHg)

Explanation: The equation calculates the rate at which gas diffuses across the alveolar-capillary membrane based on volume and pressure gradient.

3. Importance of DL Calculation

Details: Measuring diffusion capacity helps diagnose and monitor various lung diseases including emphysema, pulmonary fibrosis, and pulmonary hypertension.

4. Using the Calculator

Tips: Enter volume in liters and pressure difference in mmHg. Both values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is a normal DL value?
A: Normal values vary based on age, gender, and body size but typically range from 25-35 mL/min/mmHg for adults.

Q2: What conditions affect diffusion capacity?
A: DL decreases in conditions that thicken the alveolar membrane (fibrosis), reduce surface area (emphysema), or decrease pulmonary capillary blood volume.

Q3: How is DL measured clinically?
A: The single-breath carbon monoxide method (DLCO) is the most common clinical test for measuring diffusion capacity.

Q4: Does altitude affect diffusion capacity?
A: Yes, diffusion capacity increases at higher altitudes due to the increased pressure gradient for oxygen.

Q5: When should DL testing be performed?
A: DL testing is recommended when evaluating dyspnea, assessing interstitial lung disease, or monitoring known pulmonary conditions.