Pipamperone concentrations and organ distribution in postmortem cases with and without overdoses

Area of Science:

• Forensic Toxicology
• Pharmacokinetics
• Postmortem Analysis

Background:

• Pipamperone is a commonly used antipsychotic with relevance in forensic investigations.
• Interpreting pipamperone intoxication cases is difficult due to scarce postmortem and pharmacokinetic data.
• Understanding organ distribution and postmortem redistribution (PMR) is crucial for accurate interpretation.

Purpose of the Study:

• To investigate the organ distribution of pipamperone in autopsy cases.
• To assess the extent of postmortem redistribution (PMR) of pipamperone.
• To aid in the interpretation of pipamperone-related death investigations.

Main Methods:

• Development and validation of a liquid-liquid-chromatography with tandem mass spectrometry (LC-MS/MS) method for pipamperone detection.
• Quantification of pipamperone in heart blood, femoral blood, and various organ homogenates (brain, liver, kidney) from 32 autopsy cases.
• Analysis of other body fluids including urine, CSF, and gastric content.

Main Results:

• Pipamperone concentrations detected: 0.82-19 mg/L (femoral blood), 1.0-36 mg/L (heart blood), and up to 315 mg/kg (liver tissue).
• Heart to femoral blood ratios (H/F) ranged from 0.5 to 3.9 (mean 1.5), suggesting moderate PMR.
• Fatal intoxication was suspected in four cases with the highest blood concentrations.

Conclusions:

• Pipamperone exhibits insignificant to moderate postmortem redistribution.
• The observed PMR complicates the interpretation of pipamperone concentrations in autopsy cases.
• Careful assessment of drug concentrations, considering potential postmortem increases, is essential.