Postmortem computed tomography angiography, contrast medium administration and toxicological analyses in urine

Area of Science:

• Forensic Toxicology
• Postmortem Investigations

Background:

• Postmortem angiography uses contrast agents that may contaminate biological samples.
• This contamination could potentially affect toxicological analysis and findings.

Purpose of the Study:

• To determine if postmortem angiography alters toxicological results in urine.
• To assess the impact of contrast medium dilution on molecule concentration in various biological samples.

Main Methods:

• Compared toxicological results from urine collected before and after angiography.
• Analyzed undiluted and diluted samples (1% and 3% contrast) of urine, bile, and other fluids.
• Included 50 cases with angiography and 50 without.

Main Results:

• Observed differences in identified molecules in urine samples collected pre- and post-angiography in some cases.
• Diluted samples generally did not show significant alterations in toxicological interpretation, except for THC and its metabolites.
• Contrast medium did not significantly impact most molecule concentrations in various biological fluids.

Conclusions:

• Postmortem toxicology can often be performed on samples collected after angiography.
• However, for comprehensive analysis, especially for certain molecules like THC, pre-angiography sample collection is advisable.
• Collecting biological fluids prior to contrast medium injection remains the recommended practice.