Enantioselective Quantification of Amphetamine and Metabolites in Serum Samples: Forensic Evaluation and Estimation of Consumption Time.

In forensic toxicology, amphetamine intoxications represent one of the most common case groups and present difficult questions for toxicologists. Estimating the time of consumption and the current influence of the stimulant is particularly difficult when only total amphetamine concentrations are considered. Stereoselective analysis and the consideration of metabolites can provide valuable information to facilitate interpretation. An enantioselective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detection of amphetamine, norephedrine and 4-hydroxyamphetamine was developed. Validation showed satisfactory selectivity, sensitivity, linearity (0.5-250 ng/mL), precision and accuracy for all enantiomers. The method was applied to a collective of 425 forensic serum samples and 30 serum samples from psychiatric inpatients stating their last time of amphetamine consumption. Norephedrine and 4-hydroxyamphetamine were detected more frequently at higher amphetamine concentrations and at lower amphetamine (R)/(S) concentration ratios, possibly indicating recent consumption. Mean (R)/(S) ratio of amphetamine was 1.14, whereas higher ratios (mean 1.36) were found for amphetamine concentrations below 100 ng/mL. The (R)/(S) ratios of psychiatric inpatients significantly correlated with the reported time intervals to last consumption. The use of amphetamine (R)/(S) ratios and the simultaneous detection of metabolites are promising factors that can facilitate estimation of consumption time and current impairment.

Degree of Postictal Suppression Depends on Seizure Induction Time in Magnetic Seizure Therapy and Electroconvulsive Therapy.

OBJECTIVES: Anesthesia is required for both magnetic seizure therapy (MST) and electroconvulsive therapy (ECT), although it has anticonvulsant properties. In this case, bispectral index (BIS) monitoring, a specific electroencephalogram-derived monitoring, can be used to find the optimal seizure induction time during anesthesia to elicit adequate seizures. A measurement of seizure adequacy in electroencephalogram is the postictal suppression. The purpose of this study was to investigate the influence of seizure induction time on the degree of postictal suppression by comparing BIS versus no-BIS monitoring in MST and ECT. METHODS: Twenty patients with treatment-resistant depression were randomly assigned to either MST or ECT. Each patient underwent 3 treatments with the determination of seizure induction time by defined prestimulation BIS (BIS condition) and 3 treatments with determination of seizure induction time by controlled clinical trial protocol (no-BIS condition). Statistical analysis was calculated by repeated-measures analysis of variance. RESULTS: The degree of postictal suppression was more pronounced in both MST and ECT, with BIS monitoring. In this connection, no differences between MST and ECT were found. Seizure induction time was significantly later in the BIS condition (181.3 ± 6 seconds) compared with the no-BIS condition (114.3 ± 12 seconds) (P < 0.001). CONCLUSIONS: Adequacy of seizures, in the form of the degree of postictal suppression, was superior by determining the seizure induction time with BIS in both MST and ECT. Further research is needed to investigate the correlation between the degree of postictal suppression and treatment response.