ABSTRACT

Postmortem redistribution (PMR) refers to the changes that occur in drug concentrations after death. It involves the redistribution of drugs into blood from solid organs such as the lungs, liver and myocardium. Postmortem drug concentrations show variations depending on sampling sites and characteristics of the drugs. Drug properties such as volume of distribution, lipophilicity, and pKa are important factors. Basic, lipophilic drugs with a volume of distribution greater than 3 l/kg are most likely to undergo PMR.

The anatomical location of blood sampling can influence the drug concentration. Blood collected at autopsy is an important biological sample and consists of cardiac and peripheral blood. The cardiac blood concentrations are, in general, higher than peripheral blood concentrations. Postmortem drug concentrations in peripheral blood were reported to be similar to antemortem drug concentrations. Therefore blood collected from peripheral sites is recommended for drug analysis and interpretation. While many laboratories is determining the redistribution in postmortem cases, they use cardiac/peripheric blood (C/P) concentration ratio. When this ratio is substantially greater than unity, the drug is considered to exhibit postmortem redistribution. The liver to peripheral blood (L/P) ratio is also evaluated as a marker of postmortem redistribution because of postmortem drug concentration is more stable in tissues. Confidence of drug concentration measured in postmortem blood is decreased and the importance of tissue analysis comes back on the agenda again.

The interpretation of concentrations of drugs measured in the postmortem period is complex. In this reason, in our study “What is the postmortem redistribution and Which biological samples should be taken for the correct and reliable assessment of the toxicological data?” answers to the questions will be presented in the literature.