A seven-autopsy quetiapine report did not contain seven fully quantified heart–femoral blood comparisons. Only three cases supplied numerical concentrations at both sites. Those pairs suggested that collection site matters, but they did not measure the amount by which blood concentrations changed after death.
Count the actual paired observations
Anderson and Fritz reported seven Los Angeles County coroner cases in 2000. Heart blood was examined in all seven cases, while femoral venous blood was collected in five. In two of those five, both blood results were present below 0.10 mg/L. Three pairs therefore supported an ordinary calculation using two quantified values.
A missing femoral specimen is different from a negative femoral test. A positive result below the quantitation limit is different from an exact numerical concentration. Neither category should be silently converted into an additional fully quantified pair.
What were the three pairs?
| Case | Heart blood, mg/L | Femoral blood, mg/L |
|---|---|---|
| 3 | 5.1 | 0.95 |
| 4 | 1.9 | 1.4 |
| 5 | 0.43 | 0.26 |
Heart blood was higher in each of these three cases, but the size of the difference varied. The authors interpreted the observations as suggesting possible postmortem redistribution. They also acknowledged that femoral specimens had not been submitted for every case.
These were descriptive paired findings, not a reported statistically significant experiment showing a uniform increase. The table cannot justify applying the largest difference, or an average of the three differences, as a universal correction to another person’s heart blood.
Collection and analysis define the comparison
All specimens were obtained at autopsy. Heart blood was preserved with sodium fluoride, and femoral blood with sodium fluoride and potassium oxalate. All biological specimens were kept at 4°C. The report did not provide a uniform death-to-autopsy interval or a serial blood-collection sequence.
The workflow used GC–NPD for presumptive identification and quantitation, followed by GC–MS confirmation against a pure standard. The reported assay was linear from 0.10 to 3.0 mg/L; its quantitation limit was 0.10 mg/L, and a detection limit was not established.
The case-3 heart result of 5.1 mg/L exceeded the stated linear range. The paper did not describe how that particular above-range result was brought into range by dilution. Preserve the published value as a reported finding while recognizing that this account does not independently document its complete dilution validation.
Two postmortem sites are not a before-and-after experiment
No paired antemortem measurement was presented for these three decedents. A difference between heart and femoral blood at autopsy therefore did not quantify the rise from life to death at either site. It also did not identify the exclusive source of any redistributed drug.
Other drugs and circumstances contributed to the death interpretations. The study did not reconstruct an ingested dose, validate an impairment threshold or establish quetiapine as the sole cause of these deaths.
Use the comparison for its supported purpose
Keep both measured values and their sites visible. The useful conclusion is that a heart result should not be substituted automatically for a femoral result. A new case still requires its own collection record, analytical support and causal assessment.
Brain tissue poses a separate comparison problem: see quetiapine brain–blood ratios and their limits.
Primary source
Anderson DT, Fritz KL. Quetiapine (Seroquel) Concentrations in Seven Postmortem Cases. Journal of Analytical Toxicology. 2000;24:300–304. doi:10.1093/jat/24.4.300.
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