From an article in the Poison Review from February 13, 2010,
...The toxicology tests determined the following:
Propofol: Heart blood – 3.2 mcg/ml; Hospital blood – 4.1 mcg/ml; Femoral blood – 2.6 mcg/ml
Lidocaine: Heart blood - 0.68 mcg/ml; Hospital blood – 0.5 mcg/ml; Femoral blood – 0.34 mcg/ml
Lorazepam: Heart blood – 0.162 mcg/ml
Diazepam and midazolam were present in trivial quantities.
Baselt’s textbook The Disposition of Toxic Drugs and Chemicals in Man (7th edition) mentions that in 5 fatal cases of acute propofol poisoning, postmortem blood propofol levels ranged from 0.5 – 5.3 mcg/ml. Dr. Selma Calmes, the anesthesiology consultant, concluded that “The levels of propofol found on toxicology exam are similar to those found during general anesthesia for major surgery (intra-abdominal) with propofol infusions, after a bolus induction”.
Note that the level of heart blood propofol at autopsy was higher than that found in the femoral blood. This suggests that propofol undergoes the process of postmortem redistribution. In this phenomenon, after death a drug diffuses out of tissues and into the blood pool, producing a result somewhat higher than the actual level at the moment of death. This effect is more marked in blood obtained from central locations (heart, central vessels) compared to blood drawn from peripheral vessels such as the femoral vein. It is interesting to note that in in this case, the propofol level measured on samples of the hospital blood was higher than either postmortem level. This may be because any intravenous fluid administered to Mr. Jackson during resuscitation in the emergency department diluted the concentration of the drug....
Propofol was found at autopsy in Michael Jackson’s stomach contents in a very small concentration — less than 1:30 of the concentration in the blood. This is most likely because, after death, the drug diffused out of the circulatory system and into the stomach.
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