One of the newest ways to treat equine wounds is carbon dioxide therapy. However, the effectiveness of the treatment in horses is questionable. Dr. Angela Gaesser, DVM, DACVS-LA, from the University of Pennsylvania, said at a convention of the American Association of Equine Practitioners that carbon dioxide therapy does not appear to speed wound healing in horses but might decrease the size of the wound.

Carbon dioxide has shown promise in humans with chronic wounds due to diabetes. However, lower limb injuries in horses are difficult to heal due to skin tension, lack of underlying soft tissue, and the high motion of the legs, which leads to excessive granulation tissue, called proud flesh.

In a blind study on wound healing and skin graft acceptance in horses, six horses with small and large wounds on the forelegs were monitored for healing over a period of 28 days.

In a course of 11 treatments, the horses received carbon dioxide applied to one leg for 20 minutes, while the control leg was only treated with room air. After one week of treatment, 10 skin grafts were applied to the large wounds. All wounds were examined on the 28th day.

The amount of healing, the presence of proud flesh, and biopsies were looked at. Results showed there was no difference in the rate of healing between the carbon dioxide-treated wounds and those treated with room air. The study showed there was also no difference in skin graft acceptance rates as skin grafts were successful in wounds treated with room air or carbon dioxide.