Forensic Toxicity Flashcards
what is medical examiner system
its headed by a forensic pathologist (MD)
what is a coroner system
it may not be headed by a physician
what are 2 things that you do in clinical toxicology
- emergency screening (overdose)
- therapeutic drug monitoring
when do you do clinical toxicology testing
if it is likely to influence treatment of the patient
why do we do forensic toxicology
for legal purposes
what are 4 examples of forensic toxicology
- postmortem (cause of death)
- impaired driving/sexual assault
- workplace drug testing
- sports
what kind of specimen do you get from veins post mortem + why
whole blood (not serum or plasma) because the blood hemolyzes
what are 6 examples of tissues used for post mortem toxicology
-whole blood
-vitreous (eye)
-liver
-urine
-stomach contents
-hair
etc
what is the main methodology for forensic tox
GC/MS(MS) and LC/(Q)TOF
what are 2 main differences for instrumentation for clinical and forensic tox (so these 2 points are about forensic)
1-does not rely only on immunoassay
2-must use better extraction and chromatography
is blood reliable own its own for assessing the presence of alcohol at the time of death + why
no because postmortem BAC can increase (from bacteria and contamination)
what part of the body is better than blood when it comes to assessing alcohol
the vitreous of the eyeball
what is the main mechanism of postmortem redistribution
release and diffusion from major organs
what 2 things does postmortem redistribution dependent on
time and concentration dependent
what are candidates of postmortem redistribution (2)
high volume of distribution (like 3L/kg)
“basic character”
how much can concentrations increase with postmortem redistribution
2-10 fold
what are the 4 orders of decreased postmortem redistribution
cardiac > subclavian > femoral > antemortem
what is antemortem
when the sample is taken before death
are central or more distant areas more effected by postmortem redistribution
central
what is bad about postmortem redistribution
it can lead to mis-interpretation of toxicological results
what are 4 main difficulties of interpreting postmortem data
- dont know when drug was last taken
- dont know metabolism for person
- increase and decrease conc
- dont know tolerance
can you take a post mortem drug and then figure out the concentration
no, because of metabolism, tolerance… not that easy
why is it much tricker to interpret postmortem levels of opioids
because there is a wide range of tolerance levels
what is the drug that the kid died from (7 yo ADD)
imipramine
how does imipramine get metabolized
CYP2D6 and CYP3A4