Shallow respirations are characterized by which change in tidal volume?

• A. Tidal volume remains unchanged
• B. Tidal volume is markedly reduced
• C. Respiratory rate increases
• D. Oxygen saturation improves

Answer: (B)

Shallow respirations involve taking in smaller breaths, so the amount of air moved with each breath—tidal volume—decreases significantly. Tidal volume is the volume of air inhaled and exhaled with a normal breath, and when breaths are shallow, less air enters the lungs per breath, leading to a markedly reduced tidal volume. While the rate of breathing may change, the key point here is the amount of air per breath. Oxygen saturation isn’t a direct measure tied to breath depth and can vary, and it isn’t the defining change described by shallow breathing.