Tidal volume is defined as which of the following?

Tidal volume is defined as which of the following?

• A. Volume of gas delivered each breath
• B. Volume of air inspired from baseline to peak during normal breathing
• C. Total air in the lungs after maximal inhalation
• D. Residual air left after exhalation

Answer: (A)

Tidal volume is the amount of air moved with each normal breath. It represents the volume inhaled or exhaled from end-expiration to end-inspiration during quiet, resting breathing—the gas delivered per breath. This is why it’s described as the volume of gas delivered each breath. It’s not the total air in the lungs after a maximal inhalation (that’s total lung capacity) and not the air left after full exhalation (that’s residual volume). In a healthy adult, tidal volume is typically about 500 mL per breath, varying with size and conditioning.

Tidal volume is the amount of air moved with each normal breath. It represents the volume inhaled or exhaled from end-expiration to end-inspiration during quiet, resting breathing—the gas delivered per breath. This is why it’s described as the volume of gas delivered each breath. It’s not the total air in the lungs after a maximal inhalation (that’s total lung capacity) and not the air left after full exhalation (that’s residual volume). In a healthy adult, tidal volume is typically about 500 mL per breath, varying with size and conditioning.