Characteristics and circumstances of death related to the self‐administration of ketamine

Abstract

Background and aims Ketamine is used for anaesthesia, sedation and the treatment of mood disorders, but is also widely used for non‐medical purposes. This study aimed to: (1) determine the characteristics and circumstances of all recorded cases of self‐administered ketamine‐related death in Australia, 2000–19 and (2) determine the toxicology and major organ pathology of cases. Design Retrospective study of all Australian cases in which self‐administered ketamine was a mechanism contributory to death, retrieved from the National Coronial Information System. Setting Australia‐wide. Cases Sixty‐eight cases, with a mean age of 35.2 years (standard deviation = 11.5, range = 16–63), 76.5% male. Measurements Information was collected on cause of death, demographics, circumstances of death, toxicology and major organ pathology. Findings Death was attributed to toxicity in 82.3% of cases (accidental, 58.8%; deliberate, 23.5%), suicide by violent means (8.8%) and traumatic accident (8.8%). In six cases the decedent had been prescribed ketamine. In 32.4% the final route of ketamine administration was by injection. The fatal incident predominantly occurred in a private environment (72.1%). Ketamine was present in the blood of 90.1% and other biomarkers in the remainder. The median blood ketamine concentration was 0.2 mg/l (0.02–6.9 mg/l). Other drugs were detected in 95.5% of cases: opioids (59.1%), hypnosedatives (57.6%), psychostimulants (50.0%), alcohol (27.3%), Δ‐9‐tetrahydrocannabinol (18.2%), antidepressants (28.8%) and antipsychotics (9.1%). Pulmonary oedema was present in 82.2% of cases that underwent autopsy and pneumonia in 26.7%. Conclusions The typical case of self‐administered ketamine‐related death in Australia, 2000–19, was a male in his mid‐30s who had used multiple drugs, with the fatal incident most commonly occurring in a private setting. Death due to accidental drug toxicity was the most common manner of death, but suicide was highly prevalent.

Recreational ketamine-related deaths notified to the National Programme on Substance Abuse Deaths, England, 1997–2019

“…In other studies, the average/mean number of post-mortem drugs recorded in ketamine-related deaths is not provided. The profile of drugs found at post-mortem overlaps with both those found in San Francisco (San Nicolas and Lemos, 2015) and Australia (Darke et al, 2020). The main substances recorded in the NPSAD post-mortem toxicology were: alcohol (41%), cocaine (41%), heroin/morphine (31%), diazepam (28%), MDMA (20%), cannabis (18%) and methadone (10%).…”

“…This study found that the most common manner of death (i.e. the determination by a coroner or medical examiner as to how a disease or injury led to death) recorded in England during the period 1999-2019 for recreational ketamine-related deaths was accidental (83%) and accounted for a much higher proportion of deaths than in comparable studies: San Nicolas and Lemos (2015) = 17/25; Darke et al (2020) = 40/68, whereas other studies have recorded higher levels of suicides, for example 32% by Darke et al (2020) compared to our study (< 6%), the case definitions are not identical.…”

“…This study indicates that the underlying cause of death (initial condition or cause in the train of events leading to death, as determined by a pathologist or medical examiner) was typically accidental poisoning/intoxication (Table 4). Unfortunately, underlying (distal) cause of death is not given in other comparable studies (Darke et al, 2020;Gill and Stajíc, 2000;San Nicolas and Lemos, 2015). However, the immediate (proximate) causes of death are in alignment with these studies, for example accidental intoxication.…”

“…The latter is more in line with the remainder of NPSAD deaths during the period 1999-2019. Darke et al (2020) examined 68 cases of self-administered ketamine-related death in Australia during 2000-2019, following principles introduced and advocated by NPSAD over two decades ago, and using similar coronial sources of information. Compared to the Australian cases, NPSAD ketamine-related decedents tended to be younger (31.2 vs. 35.2 years), more likely to be male (84% vs. 77%) and to die of an accidental overdose/ toxicity (83% vs. 59%).…”

“…The largest non-UK studies up until June 2020 were: (a) reports on 15 deaths that occurred in 1997–1999 in New York City ( Gill and Stajíc, 2000 ), and (b) very basic summary information on 11 deaths in Wuhan, China, in 2005–2017 ( Li et al, 2020 ). However, Darke et al (2020) have recently examined 68 cases of self-administered ketamine-related death in Australia, 2000–2019; of which, 22 were considered suicides.…”