Lymphology Association of North America (LANA) Practice Exam

Which example does NOT represent high volume (dynamic) insufficiency of the lymphatic system?

1. Genital edema due to liver metastases

2. Bilateral lower extremity edema secondary to congestive heart failure

3. Upper extremity edema after axillary lymph node dissection

4. Generalized edema due to hypoproteinemia

The correct answer is: Upper extremity edema after axillary lymph node dissection

High volume (dynamic) insufficiency of the lymphatic system refers to situations where there is an increased volume of interstitial fluid that the lymphatic system cannot adequately drain. This typically occurs in conditions that lead to an overload of the lymphatic drainage system. The example involving upper extremity edema after axillary lymph node dissection reflects a condition often categorized as a low volume (static) insufficiency. This occurs because the surgical removal of lymph nodes can lead to disruption or impairment of lymphatic drainage in that area, causing fluid to accumulate there despite normal fluid production levels. The lymphatic system is unable to compensate for the normal amount of fluid being produced, leading to localized edema. In contrast, conditions such as genital edema due to liver metastases, bilateral lower extremity edema secondary to congestive heart failure, and generalized edema from hypoproteinemia involve scenarios where the lymphatic system may become overwhelmed by excess fluid that it typically would manage, thus reflecting dynamic insufficiency. In these cases, the system fails to handle the increased fluid volume due to systemic or localized factors, resulting in swelling.