Patient was educated that excess of fluid in the circulation can cause edema as follows:

1. Excess fluid in the circulation can result in high pressure in the tiny blood vessels, which are called capillaries.
2. This excess pressure within the capillaries can result in fluid leaking from the capillaries into spaces between the tissues.
3. Salt has the potential to retain water in the circulation. So, excess sodium in the blood can result in retaining excess water and can result in high pressure within the capillaries.
4. Congestive heart failure can result in fluid back up and increased pressure in the blood vessels, contributing to fluid leakage and edema.
5. Also, conditions such as renal failure can result in fluid retention and excess fluid volume contributing to high pressure in the circulation, resulting in fluid leakage and edema.