National Physical Therapy Examination (NPTE) Modalities Practice Exam

The purpose of the "on-off" time in intermittent compression therapy is to allow for blood flow return during the off period. This is crucial for promoting venous return and managing swelling. When the compression is applied (the "on" phase), it helps to reduce edema by applying pressure to the extremity, encouraging fluid to move out of the interstitial spaces. When the compression is released (the "off" phase), it creates a window for blood flow to return to the area without the restriction of the applied pressure. This cycle helps maintain venous circulation and prevents the risk of stagnant blood flow, which could lead to complications such as thrombosis.

The continuous pressure option would inhibit proper blood flow return and disrupt the benefits provided by the intermittent nature of the therapy. Minimizing discomfort is related to patient tolerance, but it isn't the primary function of the on-off cycle. Consistent temperature regulation is not directly related to the mechanism of intermittent compression therapy, as its primary focus is on managing pressure and promoting circulation. Thus, the intermittent nature of the on-off timing specifically serves to facilitate improved blood flow during the off periods, positioning the second option as the purpose of this therapeutic modality.