Postmortem Brain and Blood Reference Concentrations of Alprazolam, Bromazepam, Chlordiazepoxide, Diazepam, and their Metabolites and a Review of the Literature

Louise Skov, Karen Marie Dollerup Holm, Sys Stybe Johansen, Kristian Linnet

17 Citations (Scopus)

Abstract

To interpret postmortem toxicology results, reference concentrations for non-toxic and toxic levels are needed. Usually, measurements are performed in blood, but because of postmortem redistribution phenomena this may not be optimal. Rather, measurement in the target organ of psychoactive drugs, the brain, might be considered. Here we present reference concentrations of femoral blood and brain tissue of selected benzodiazepines (BZDs). Using LC-MS/MS, we quantified alprazolam, bromazepam, chlordiazepoxide, diazepam, and the metabolites desmethyldiazepam, oxazepam and temazepam in postmortem femoral blood and brain tissue in 104 cases. BZDs were judged to be unrelated to the cause of death in 88 cases and contributing to death in 16 cases. No cases were found with cause of death solely attributed to BZD poisoning. All BZDs investigated tended to have higher concentrations in brain than in blood with median brain-blood ratios ranging from 1.1 to 2.3. A positive correlation between brain and blood concentrations was found with R(2) values from 0.51 to 0.95. Our reported femoral blood concentrations concur with literature values, but sparse information on brain concentration was available. Drug-metabolite ratios were similar in brain and blood for most compounds. Duplicate measurements of brain samples showed that the pre-analytical variation in brain (5.9%) was relatively low, supporting the notion that brain tissue is a suitable postmortem specimen. The reported concentrations in both brain and blood can be used as reference values when evaluating postmortem cases.

Original languageEnglish
JournalJournal of Analytical Toxicology
Volume40
Issue number7
Pages (from-to)529-536
Number of pages8
ISSN0146-4760
DOIs
Publication statusPublished - 1 Sept 2016

Fingerprint

Dive into the research topics of 'Postmortem Brain and Blood Reference Concentrations of Alprazolam, Bromazepam, Chlordiazepoxide, Diazepam, and their Metabolites and a Review of the Literature'. Together they form a unique fingerprint.

Cite this