Using oxygen to facilitate wound healing is important, and studies have demonstrated that treatments such as hyperbaric oxygen therapy (HBOT) improve the healing of chronic venous ulcers in a randomised, controlled clinical trial (Winfield, 2014). However, some patients may not tolerate systemic HBOT side effects; health professionals/patients may find HBOT too expensive; or clinicians may not be able to gain access to a hyperbaric chamber. Sometimes, the cardiovascular system is inadequate for carrying the oxygenated blood to the wounded tissue, or the tissue is so oedematous that the oxygen cannot reach the wound well (Sheffield, 1988).