The Use of Non-Contact Low Energy Ultrasound Therapy* to Treat Frostbite for Post-Op Complication

Introduction: Frostbite is an injury caused by freezing of the skin and underlying tissue whereupon the skin becomes very cold and red, then numb, hard and pale. Frostbite occurs in different stages based on severity – frostnip, superficial frostbite and deep frostbite. Frostnip, the mildest form of frostbite, does not permanently damage skin. Superficial frostbite is reddened skin that turns pale and may result in fluid-filled blisters appearing 12-36 hours after rewarming the skin. Deep frostbite affects all layers of skin, including the tissue that lie below. The skin turns white or bluish gray and large blisters form 24-48 hours after rewarming. Afterwards, the area turns black and hard as the tissue dies.

Case Report: The patient is a 48-year-old female with no significant medical history that presented with tissue necrosis after leaving ice on continuously for 38 hours post-op osteotomy of 1st and 5th metatarsal on the right foot. Arterial testing showed no significant atherosclerosis or hemodynamically significant stenosis. Sutures were intact with subepidermal blistering noted. Incision and drainage was done by the surgeon for the iatrogenic wound fluid.  Non-contact low energy ultrasound therapy* was used twice a week for 8 treatments along with supporting treatment of dimethicone small molecule protective skin barrier and silver hydrogel with antimicrobial dressing over the area post granulation.

Discussion: The use of non-contact low energy ultrasound therapy* provided for an increase in local perfusion and improved vasodilation to the wound. The decrease in bioburden, local wound inflammation and accelerated tissue regeneration to the area was observed. The patient reported a decrease in pain during treatment. The area was well preserved and went on to full closure within 10 weeks of initiating the treatment.