What is the recommended rise/fall setting range on a power injector to reduce catheter whip?

• A. 0.1-0.3
• B. 0.3-0.6
• C. 0.6-0.9
• D. 0.9-1.2

Answer: (B)

Controlling how quickly the injector ramps the flow up and down smooths the contrast jet and reduces abrupt pressure transients at the catheter tip. A moderate rise/fall setting provides a gradual, steady increase to the target rate and a gentle return to zero, which minimizes the forces that can cause the catheter to whip inside tortuous vessels or with small catheters.

If the ramp is too slow, timing of the contrast bolus can be affected and image acquisition may be suboptimal. If the ramp is too rapid, the sudden jet can generate larger transient forces, increasing catheter movement. The middle, moderate range offers a balanced approach: it reduces catheter whip while preserving timely, diagnostic contrast delivery.