Blood blisters? Could these be pressure sores? You have to offload the pressure to the heels and put something on them for protection (duoderm, mepilex) and wait for them to heal. Sometimes the area that looks like a blood blister will just dry up and come off with nice healed skin underneath. If you don't keep the pressure off or if the damage is deep it may break down further.
Thanks for the info. They are definitely pressure acquired and I staged them accordingly. I did offload pressure to the area. The blisters took a long time to dry up and they are finally showing signs of improvement. I had tried several different dressings including the duoderm you suggested. Thanks again.