Wound care and home health

Can anyone help me with a wound care question? If a Medicare pt has wound care {wound vac} but also has home health care that can not care for the wound vac. How do we get Medicare to pay us for these services?

Wound vac

Home health is responsible for care of wound vac. This is a Part A benefit and you cannot split this out. I would check on this again. Home health has RNs so why can't they do this?

Home health wound care

If the patient is not under home health care how does the doc code for wound care done at the patients home?