Red swollen feet are common in PN. The red colour comes from blood. The feet veins need help from the leg muscles to press the blood back to the heart, and in PN we lack strength in leg muscles.
What can be done is;
Keep feet high, make pulsating contractions of leg muscles and let someone gently massage the blood in the right direction.
Heat, humidity and meds can influence the function, and of course the condition of the heart.
Besides: Greetings to all, just found this wonderful page.
Per, Norway