Wound healing requires adequate oxygen delivery to the area of injury which is dependent on circulating blood hemoglobin (hgb) levels. So a common question is: ‘What is the optimal hgb level for a patient in need of a split thickness skin graft?’.
Historically, a hgb of 10 g/dl has been felt to be low, but adequate for skin graft and donor site healing. However, particularly in malaria prone areas, patients routinely have hgb levels lower than 10 on a chronic basis. Many surgeons working in rural areas without easy access to blood transfusion capabilities and whose patients have chronic anemia, have felt that hgb levels as low as 8 or even 6 or g/dl can have successful skin grafting (“success” means that the graft takes and the donor site heals). Now there is a study that supports this practice.
A study was published in the 2009 Indian J of Plastic Surgery by Agarwal, Prajapati and Sharma which shows that skin grafting can be successful in patients with hgb levels as low as ~6 g/dl. But in patients with malnutrition, dm, or other chronic conditions, higher hgb levels are warranted.
So save precious blood resources- skin grafts will heal despite these low hgb levels. But remember, the patient will lose additional blood through harvesting of the skin graft and wound debridement. So be careful, especially when doing large skin grafts. A useful way to decrease blood loss at the graft donor site is to either:
- Inject the area with local anesthetic with epinephrine, and/or
- apply gauze soaked in dilute epinephrine (for example add one ml of 1:1000 epinephrine to 500ml of saline) to the donor site area after the skin graft has been harvested.