A freshly applied split-thickness skin graft does not receive oxygen until what occurs?

• A. Arterial blood flow is re-established.
• B. Capillaries can grow into it.
• C. Immediately after placement.
• D. The graft is covered by a protective dressing.

Answer: (B)

The key idea is how a skin graft gets its oxygen in the early period after placement. At first, the graft survives mainly through plasmatic imbibition—oxygen and nutrients diffuse from the wound bed through the graft via body fluids. Oxygen delivery from the host’s blood isn’t established yet. Oxygenation then shifts to true revascularization when capillaries from the recipient bed grow into the graft, a process called inosculation. Once capillary ingrowth occurs, the graft gains its own blood supply and continuous oxygenation can be provided by the host circulation. So, the graft does not receive oxygen from the host until capillaries can grow into it.