when the lymphatic vessels are damaged they will not be able to remove all the excess interstitial fluid from tissues. So edema is seen in the arm of that person because there is excess fluid in the interstitium.
Ways to reduce edema would be movement and elevation of that area(your arm) compressing and messaging it. These all help with the fluid entering the lymphatic vessels and leaving the interstitium. Another important factor is reducing ur salt intake so the edema doesn’t progress.
