Medicolegal implications of drugs and chemicals detected in intracranial hematomas.

The purpose of this study was to determine how drug findings in intracranial hematomas should be assessed in forensic autopsy cases. Six cases in which intracranial hematomas containing drugs and chemicals were detected were examined in this study. Of the six cases, five were positive for drugs and chemicals that had been self-administered by the victims prior to injury. Post-traumatic time interval from injury to death was in the range 10 to 65 h. In two individuals who were positive for norephedrine or toluene, the concentrations of these substances were much higher in the intracranial hematomas than in heart blood. In an individual who was positive for phenobarbital, its concentration was only a little higher in the intracranial hematoma than in heart blood. In the remaining two cases, substantial quantities of ethanol were detected in the intracranial hematomas, but little ethanol was detected in heart blood. In three cases, some drugs were administered at hospital after the injuries. The time interval from the initial drug administration to death was 19 to 60 h. In two individuals given phenytoin and/or lidocaine intravenously, substantial amounts of these drugs were detected in the intracranial hematomas. In an individual given diazepam intravenously, a substantial quantity of diazepam was detected in heart blood, but not in the intracranial hematoma. Toxicological analysis of intracranial hematomas may be useful not only for determining whether individuals were under the influence of ethanol at the time they were injured, but also for detecting pre-traumatic usage of other drugs and chemicals. However, the medical record should be reviewed thoroughly from a toxicological view point if victims underwent medical treatment prior to death because drugs administered for the purpose of medical treatment can disseminate into preexisting intracranial hematomas, depending on the size of the hematomas.