Long-Term Detection In Hair Of Zolpidem, Oxazepam And Flunitrazepam In A Case Of Drug-Facilitated Sexual Assault

Estimation of the time of zolpidem intake and differentiation between consumption and external contamination using MALDI-MSI for investigations on single hair samples

Estimation of drug ingestion time (event time) and distinguishing between drug ingestion and external contamination are important for interpreting hair analysis results in forensics practice. Here, we present a matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) method for in situ analysis of intact hair. We applied a longitudinal cutting method for a single hair to analysis authentic hair samples from a victim of a drug-facilitated sexual assault (DFSA) case and zolpidem-soaked hair. MALDI-MSI showed that zolpidem-positive segments distributed at 4-6 mm or 6-8 mm from the root in three single hairs of a DFSA victim collected 25 days after the event, at concentrations ranging from 0.1 to 5.7 pg mm-1, in agreement with the results from segmental analysis using liquid chromatography tandem mass spectrometry (LC-MS/MS). The estimation of drug intake time was about 20-30 days before sampling, which was consistent with the known time of drug intake. This MALDI-MS method allows imaging analysis of trace substances in a single hair and can realize the intuitive reflection of drug taking time. In addition, zolpidem applied by soaking was mainly distributed on both sides of the longitudinal hair shaft, whereas ingested zolpidem was found only in the middle of the hair shaft of the DFSA victim. The MALDI-MS images of unwashed and washed hair suggested that the amount of externally applied drug was decreased by washing, it was still present on surface layer (cuticle) sides although. Visualization using MALDI-MSI could therefore distinguish between drug ingestion and contamination by reflecting the distribution and deposition site of the drug in hair.

Choking in patients with neurological disorders and role of drug-induced dysphagia

Choking is a type of asphyxia due to the internal obstruction of airways by foreign material, quite always food. Most choking deaths are accidental and occur so quickly that may mimic a heart attack. This scenario is also known as "Cafè coronary syndrome" or "bolus death". At autopsy, pieces of under-chewed food are commonly lodged at, above, or in the tracheal space adjacent to the laryngeal inlet. In these fatal events mechanisms other than asphyxia can be also involved, such as a vasovagal episode (by stimulation of the autonomic nerve plexus of the laryngeal inlet) or swallowing impairment. Swallowing is a complex, semi-automatic process that can be affected by various disorders (i.e. dementia, Parkinson, neurological injuries, etc.), senility and external factors causing oropharyngeal dysphagia (OD). Among these factors, several drugs have been also associated with impaired swallowing, including drugs acting on the CNS like antipsychotics and antiepileptics. Three cases of witnessed bolus deaths are reported. All victims were affected by neurological defects and took medications acting on CNS. In all cases, at autopsy pieces of food were found distributed from the laryngeal inlet along the main axis of the trachea up to the large bronchi over the bifurcation. Additional autopsy findings were represented by facial congestion and cyanosis, subepicardial petechiae and pulmonary emphysema.

The Evolution Toward Designer Benzodiazepines in Drug-Facilitated Sexual Assault Cases

Drug-facilitated sexual assault (DFSA) is a crime where the victim is unable to provide sexual consent due to incapacitation resulting from alcohol or drug consumption. Due to the large number of substances possibly used in DFSA, including illicit, prescription and over-the-counter drugs, DFSA faces many toxicological challenges. Benzodiazepines (BZDs) are ideal candidates for DFSA, as they are active at low doses, have a fast onset of action and can be easily administered orally. The last decade has seen the emergence of designer benzodiazepines (DBZDs), which show slight modifications compared with BZDs and similar pharmacological effects but are not controlled under the international drug control system. DBZDs represent an additional challenge due to the number of new entities regularly appearing in the market, their possibly higher potency and the limited knowledge available on their pharmacokinetic and pharmacodynamics properties. Many BZDs and DBZDs have a short half-life, leading to rapid metabolism and excretion. The low concentrations and short time windows for the detection of BZD in body fluids require the use of highly sensitive analysis methods to enable the detection of drugs and their respective metabolites. This review discusses the current state of the toxicological analysis of BZDs and DBZDs in forensic casework and their pharmacokinetic properties (i.e., absorption, distribution, metabolism, and elimination), as well as their analysis in biosamples typically encountered in DFSA (i.e., blood, urine and hair).