Certified Wound Ostomy Nurse (CWON) Practice Test

What does the mechanism of action (MOA) of compression therapy include?

1. Increase arterial blood flow

2. Reduce interstitial fluid pressure

3. Increase interstitial tissue pressures and collapse superficial veins

4. Eliminate all venous stasis

The correct answer is: Increase interstitial tissue pressures and collapse superficial veins

The mechanism of action of compression therapy primarily focuses on increasing interstitial tissue pressures, which helps to collapse superficial veins. This is important in the treatment of venous ulcers and chronic venous insufficiency, as the compression provided prevents the veins from expanding and helps to promote better venous return to the heart. By collapsing these superficial veins and creating a higher pressure in the surrounding tissues, compression therapy can effectively reduce edema and improve overall venous circulation. In addition, the increase in interstitial pressures assists in pushing excess fluid from the interstitial space back into the capillaries, thereby reducing swelling. This action also helps with the healing of wounds by improving nutrient delivery and waste removal from the tissue. While increasing arterial blood flow might seem beneficial, compression therapy primarily targets the venous system rather than enhancing arterial flow. Reducing interstitial fluid pressure is not the primary goal; instead, the aim is to increase it to alleviate issues such as venous stasis. Though compression therapy does help to reduce venous stasis, it does not completely eliminate it, so stating that it eliminates all venous stasis would be an overstatement.