Plaster and synthetic cast temperatures in a clinical setting: an in vivo study

Previous studies have reported thermal injuries with thick cast materials and warm dip water temperatures, often much higher than is clinically applicable. The goal of this study was to assess the temperature produced in vivo by current casting techniques and materials. The study was done using clinically applicable materials and water temperatures. A single volunteer was used to test skin temperatures produced with various casting techniques. We tested several types of fiberglass and plaster of 5 or 10 layers, used soft roll of 1 or 3 layers, and used dip water temperatures of 30 °C and 40 °C. We tested 2 plaster types: Johnson & Johnson Specialist Fast Set and Specialist Extra Fast Set (New Brunswick, New Jersey). Fiberglass tested included 3M Scotchcast Poly Casting Tape and Scotchcast Plus (St Paul, Minnesota), Royce Medical Techform (Camarrillo, California), and DeBusk Classic Synthetic Tape (Powell, Tennessee). The highest temperature reached using 30 °C water temperature was 39 °C with 10 layers of 3M Scotchcast fiberglass and 1 layer of soft roll. The highest temperature reached with 40 °C water was 39.5 °C, which was reached twice: once with Johnson & Johnson Fast Set Plaster with 5 layers of plaster and 3 layers of soft roll, and once with DeBusk Classic Synthetic Casting Tape of 10 layers with 1 layer of soft roll. Under the clinically applicable conditions described in this study, using the materials we tested and with a normal vascular supply, it is unlikely that temperatures high enough to cause a burn will be produced. We caution that good clinical judgment is advised if a patient reports a cast is too hot.