- Skin preparation burns associated with chemical agents are uncommon. They occur most frequently in patients placed in the lithotomic position undergoing gynaecologic or urologic operations, the burn being on the buttocks, and in those undergoing orthopaedic operations, the burn being on the extremities and under a tourniquet. The basic mechanism involves irritation coupled with maceration and pressure. If the betadine solution has not been allowed to dry and has been trapped under the body of the patient in a pooled dependent position, such as the buttocks or under a tourniquet, the solution may irritate the skin and result in a skin burn. The irritation coupled with pressure leads to a situation analogous to that seen in the development of an acute accelerated decubitus ulcer; irritation, maceration, friction and pressure compounding each other to result in a skin burn or superficial ulcer in the skin. Our experience with three illustrative patients who presented with various burns following exposure to povidone-iodine (betadine) is described below.