Criminal poisoning with anaesthetic drugs: murder, manslaughter, or not guilty

Degradation and elimination of succinylcholine and succinylmonocholine and definition of their respective detection windows in blood and urine for forensic purposes

The muscle relaxant succinylcholine (SUX) evokes respiratory paralysis, and numerous cases of fatal SUX intoxication have been reported. Detection of SUX and its metabolite succinylmonocholine (SMC) is difficult, both due to their (bis-) quaternary structure and the extreme hydrolytic susceptibility of SUX, and data on degradation kinetics of SUX and SMC is scarce. The present study investigates the in vivo and in vitro degradation as well as elimination of both target analytes using authentic blood and urine samples from anesthetized patients. With a special focus on the urinary data and stabilization issues, this work intends to considerably enhance the forensic knowledge concerning SUX intoxications and to present the reader with practical analytical strategies to cope with such difficult cases. Eighteen subjects undergoing surgery and requiring arterial as well as bladder catheters were included in this study. Muscle relaxation was initialized with a bolus injection of 80-100 mg SUX. Blood and urine samples were either collected using paraoxonized (n = 15) or non-modified (n = 3) tubes. Sampling was performed within 6 h after SUX application following a pre-assigned schedule. Samples were processed according to a validated isotope dilution HPLC-MS/MS method using ion-pair solid-phase extraction. In blood, SUX was usually detectable for up to 10 min post-injection, while detection of SMC was possible over the whole observation period of 6 h. Effectiveness of organophosphate stabilization was proven for both analytes and is therefore recommended. In freshly secreted urine, detection windows of a minimum of 2 h as opposed to 6 h have been determined for SUX versus SMC, respectively. Considering SMC plasma kinetics, detection of the metabolite in blood and freshly secreted urine appears to be possible over a period of at least 8-24 h. Paraoxon did not enhance the stability of either target substance in urine, stabilization of urine samples is nonetheless recommended. In summary, SMC was proven to be the most promising target analyte in SUX analysis, with urine being the proposed matrix of choice for forensic applications. Furthermore, our work defines meaningful detection windows for SUX and SMC in blood and urine as routine matrices and presents sampling recommendations as well as guideline values for forensic toxicological analysis.

Fall downstairs: accident, homicide or natural death?

In homicide cases a clear anatomical or toxicological cause of death is normally evident. In the following a case is described where, without clear anatomical or toxicological cause of death, the husband of the deceased-a trained anaesthesiologist-was charged with murder. Suspicion was raised since the autopsy findings did not correspond to a fatal fall downstairs but instead could be definitely ruled out as cause of death, since intracranial bleedings and cerebral contusions, the leading causes of death in fatal falls downstairs, were missing. Further suspicion was raised since electrocardiograms (ECGs), previously stated by the accused to have been recorded personally from his wife during cardiopulmonary resuscitation (CPR), were obviously faked. Additionally, an ampule of succinylcholine was missing from his emergency case. In a trial lasting more than three quarters of a year with several witnesses and experts heard by the court, the cause of death remained unclear. However, a natural cause of death and a fatal fall downstairs were ruled out. Subsequently the husband admitted during the trial to have killed his wife without elaborating on the circumstances for legal reasons. He was sentenced to prolonged imprisonment. Of special importance was that, based on the knowledge of typical autopsy findings in fatal falls downstairs, a lethal fall downstairs could be ruled out. Therefore even negative autopsy findings are of great forensic importance.

A forensic toxicological dilemma: the interpretation of post-mortem concentrations of central acting analgesics

Dora V., a 88-year-old pensioner suffering from a hiatus hernia, died at the home of an orthopaedist and his wife, an anaesthetist, immediately after she had received a dose of 300 mg pethidine via intravenous infusion in a timeframe of about 90 min. One day before her death a befriended notary of the couple visited Dora V. and obtained a blank signature. After her death, a will was forged using this signature, rendering the couple sole heirs of Dora V.'s estate with a value of several million euros. Post-mortem toxicology was performed in three different institutes of legal medicine. The concentrations of pethidine in peripheral venous blood were between 6.1 and 6.5mg/l and 9.5 and 17.2mg/kg in brain. Pharmacokinetic calculation confirms the given dose. There was no doubt that the cause of death was acute pethidine intoxication. The accused couple claimed that this dose of pethidine was indicated to relief pain, and as the pathologists said in their expert opinions that the hiatus hernia could explain her death, the court had to acquit the accused. This very special case demonstrates that preconceived murder of a sick person with suitable analgesics cannot be proven--at least not with the methods available to forensic toxicology and pathology. This has to be taken into consideration if euthanasia will be legalised under special circumstances.

A case of serial homicide by injection of succinylcholine

The abstract of this paper was presented at the 14th Meeting of the International Association of Forensic Sciences, Tokyo in 1996. We report a bizarre criminal case of suspected serial homicide by injection of a muscle relaxant (succinylcholine). Five victims were found buried in a rural area. In two victims showing moderate decomposition (about three months after death), intense pulmonary oedema with pleural effusion was observed. Evidence of a puncture site was found in one of the victims. Succinylcholine could not be detected in the victims, but was identified in a syringe found near the corpses. The 40-mg ampule dose of succinylcholine administered intramuscularly to the victims, possibly causing prolonged apnea, was considered to be at least around the minimum lethal dose, although the combined effect of the sedation with hypnotics also used was not negligible.

Love potions and the ointment of witches: historical aspects of the nightshade alkaloids

BACKGROUND

Nightshade plants (Solanaceae) have been utilized as hallucinogenic drugs since antiquity in nearly every culture. The Solanaceae alkaloids, atropine and scopolamine, were the active substances in ointment of witches and medieval anesthetics, and in modern poisons. They are still currently used as hallucinogenic drugs. In poisonings, a dosage- and substance-dependent clinical picture occurs, with central and peripheral symptoms. Hallucinations are predominant in the middle dose range, which explains the drugs' earlier utilization for religious and prophetic purposes. Respiratory depression and arrest at high doses confirm the use of scopolamine as a lethal poison. Despite this, the nightshade alkaloids were utilized in clinical medicine in the 19th century. This is an overview of the cultural history of the nightshade alkaloids.