Which cycling ends inspiration when preset inspiratory time (Ti) is reached?

• A. Time Cycling
• B. Volume Cycling
• C. Flow Cycling
• D. Pressure Cycling

Answer: (A)

Breaths end after a fixed period in time cycling. The inspiratory time, Ti, sets how long the inspiratory phase lasts, so once that preset Ti is reached, inspiration stops and expiration begins. This differs from other cycling methods where the end of inspiration is determined by achieving a target tidal volume (volume cycling), a drop in inspiratory flow to a threshold (flow cycling), or a specified pressure criteria (pressure cycling). So ending at the preset Ti is characteristic of time cycling.