What may occur if there is a 5-second delay after lowering the blood pump speed before drawing a post-treatment blood sample?

In the context of dialysis treatment, the post-treatment blood sample is critical for evaluating the effectiveness of the session, particularly in calculating KT/V, which assesses the adequacy of dialysis. If there is a delay after lowering the blood pump speed before taking the sample, this delay can lead to an inaccurately high KT/V reading.

When the blood pump speed is reduced and then paused, residual blood in the dialyzer and bloodlines may not be fully cleared before sampling. This can result in capturing a larger volume of blood that may not have been effectively treated during the dialysis session, as it has not been exposed to the dialysate properly. Consequently, since the sample reflects blood that is less effectively filtered, the KT/V reading, which correlates to the clearance of urea and other waste products from the bloodstream, may present as higher than it actually is.

This is important to consider in clinical practice, as accurate KT/V measurements are essential for determining the adequacy of dialysis treatment, and misleading results can impact patient care decisions.