Comparative postmortem blood alcohol concentrations in cardiac and peripheral blood: a case series

Blood is an exceptionally important tissue in forensic toxicology. Determination of blood alcohol concentration (BAC) is conducted in gas chromatography with flame ionization detection using the headspace technique (HS-GC-FID). Whenever possible, postmortem blood from two districts, cardiac and peripheral, should be drawn at each autopsy. Because of the high probability of contamination, blood from the thoracic and abdominal cavities should be avoided unless no other blood matrix is available. In postmortem analysis for the determination and quantification of exogenous substances, cardiac blood tends to be more prone to redistribution than peripheral blood. Postmortem redistribution (PMR) is a phenomenon whereby the concentration of exogenous substances undergoes alterations in the body after death. The underlying mechanism is complex and still unclear; moreover, the degree of PMR can vary depending on the districts and tissues involved. Analyses conducted on peripheral (e.g., femoral) blood show greater reliability in terms of results than cardiac blood.