Circumstantial and toxicological features of deaths from self-administered intravenous anesthetic/narcotic agents

Takahito Hayashi, Claas Buschmann, Benno Riesselmann, Sonja Roscher, Michael Tsokos

For a better understanding of circumstantial and toxicological findings of fatalities resulting from self-administration of intravenous anesthetic/narcotic agents, medico-legal autopsy files of the State Institute of Legal and Social Medicine Berlin from 1998 to 2011 were reviewed retrospectively. Of a total of 15,300 autopsies, 9 cases of such deaths were identified, and all were health care professionals. Medical supplies for injection were found still on, or near, the body at the scene. Anesthetic/narcotic agents detected were classified into 3 categories, and administered solely or in combination. Propofol was the most common agent, being detected in 6 cases. In 2 out of 6 cases, propofol was detected substantially above therapeutic levels and was considered the cause of death. In the remaining 4 cases, propofol levels were within the therapeutic range, but propofol intoxication was considered as lethal due to it being administered by rapid continuous injection. In 5 cases, injection of opioid narcotics was fatal. Alongside the 2 propofol-detected cases, there was one case where a higher-than-therapeutic level of piritramide and a therapeutic level of alfentanil was identified. Despite suspected usage, remifentanil was not detected due to its rapid metabolism by elastases in one case, and sufentanil was undetectable due to putrefaction in another, but death was attributed to their potent respiratory depressant effects without respiratory assistance. Benzodiazepines were detected in 4 cases. All of them were used together with propofol or opioids, and contributed to death by inhibiting respiration. It is essential to consider means of administration as well as additive or synergistic effects of combined agents when interpreting toxicological results in such cases.