ABFM Toxicology and Cause of Death Analysis 2

Question 1

Which specimen is considered the gold standard for detecting drugs in postmortem toxicology due to its resistance to redistribution artifacts?

Accepted Answer

Vitreous humor

Answer

Vitreous humor is largely protected from postmortem redistribution and microbial degradation, making it highly reliable for toxicological analysis.

Question 2

A decedent is found with cherry-red lividity. Which toxicological finding would most support carbon monoxide poisoning over cyanide poisoning?

Accepted Answer

Carboxyhemoglobin >30%

Answer

Carboxyhemoglobin saturation above 30% is diagnostic of significant carbon monoxide exposure and distinguishes CO poisoning from cyanide, which does not elevate carboxyhemoglobin.

Question 3

Postmortem redistribution most significantly affects which class of drugs, leading to overestimation of antemortem levels?

Accepted Answer

Lipophilic basic drugs with large volumes of distribution

Answer

Lipophilic basic drugs with large volumes of distribution (e.g., tricyclic antidepressants, methadone) concentrate in solid organs and redistribute postmortem into central blood.

Question 4

During autopsy, the liver is sampled for toxicology. Which analyte is liver particularly useful for quantifying due to its high concentration there?

Accepted Answer

Acetaminophen

Answer

Acetaminophen undergoes hepatic metabolism producing a toxic intermediate (NAPQI), and its concentration in liver tissue can confirm hepatotoxic overdose even when blood levels are declining.

Question 5

Which parameter best differentiates acute ethanol ingestion from postmortem ethanol production by putrefactive organisms?

Accepted Answer

Detection of n-propanol as a marker of fermentation

Answer

n-Propanol (1-propanol) is a byproduct of microbial fermentation and its presence alongside ethanol strongly suggests postmortem production rather than antemortem ingestion.

(ABFM) American Board of Forensic Medicine Certification Practice Test

(ABFM) American Board of Forensic Medicine Certification Practice Test

ABFM Toxicology and Cause of Death Analysis 2