This book is written mainly for attorneys, physicians, and investigators who are concerned with accidents associated with electric current. It is based on approximately 50 years of personal research, augmented by experience in teaching medical and biomedical engineering students and as an expert witness in litigation involving electrical injury. The material is presented in two ways: non-technically, for attorneys and physicians, and technically, for their expert witnesses and engineers. Since there is no typical electrical accident, the accidents described and the material presented in the chapters are selected to aid the reader in explaining the cause of any particular electrical accident.
The first chapter presents a short history of electrical accidents, along with selected accident descriptions in the home, work place, and hospital. Chapter 2 deals with the fundamental processes whereby electric current stimulates excitable tissue, such as sensory receptors, nerves, and muscles. The response to the passage of low-frequency alternating current through the body-e.g., muscle stimulation, ventricular fibrillation, and burns-is covered in Chapter 3. Lightning and lightning injuries are discussed in Chapter 4. The effects of high-frequency (electrosurgical and diathermy) currents-and the types of injury encountered-are discussed in Chapter 5. Because current preferentially seeks tissues with the lowest resistivity, Chapter 6 provides knowledge of the resistivity values for tissues, organs, and body fluids, allowing estimation of the current path. The same chapter presents information on the resistance of body segments and of a contacting conductor, showing the nonlinear nature of such contacts where tissues are boiled, charred, and burned