Influence of the nature of death in biochemical analysis of the vitreous humour for the estimation of post-mortem interval

Post-mortem biochemistry as a tool for the establishment of post-mortem interval (PMI) and the nature of death is very useful in Legal Medicine. Currently, several matrices are used for these investigations, although vitreous humour is the most useful for biochemical analysis due to its stability and low susceptibility to autolytic changes. The purpose of this study was to analyse to what extent the nature of death could influence in the measurement of parameters such us potassium (K+), hypoxanthine (Hx) and uric acid in the establishment of PMI. Samples of vitreous humour were collected from the eyes of 250 dead bodies (174 males, 76 females) with a mean age of 58.75 +/- 20.84 years, mean PMI of 15.56 +/- 6.21 hours post-mortem (hpm) and different causes of death, including natural (n = 148) and violent (n = 101) deaths. The vitreous humour was treated and the resultant supernatant was used for the biochemical analysis. Multichannel Autoanalyser was used to determine the concentrations of K+ and uric acid (mmol/L), and Hx (mu mol/L) was quantified by HPLC-UV. The results showed the measurement of K+, Hx and uric acid together could be a complementary tool for establishing the PMI because these parameters provide good results.