Estimation of time since death through electric and chemical excitability of muscles

Electric and chemical excitability of muscles present a supravital reaction which is of major importance in achieving a more precise estimating of the time since death in the early post-mortem period. The purpose of this paper is to examine the electric and chemical excitability of the muscles in cases with a known time of death, in order to determine their importance in the estimation of time since death. Electric excitability and chemical stimulation have been analysed in 50 cases with a known time of death, taken for autopsy at the Institute of Forensic Medicine and Criminology in Skopje in the course of the year 2005. Testing of electric excitability of the muscles was done with a device for electric stimulation, providing a direct current of 50 mA intensity and 50 Hz frequency. Testing of chemical excitability of the eye pupils was done by injecting miotic Carbahol into the front eye chamber of the right eye and mydriatic Adrenalin HCl into the front eye chamber of the left eye. By analysis and processing of the obtained results, it was determined that the electric excitability of the muscles is of a major importance in determining the time since death within a post-mortem period of up to 10 hours and chemical excitability for a post-mortem period of up to 12 hours.