Characteristics of analytically confirmed gamma-hydroxybutyrate (GHB) positive patients in the emergency department: presentation, poly-drug use, disposition and impact on intensive care resource utilisation.

BACKGROUND: Gamma-hydroxybutyrate is a potent central nervous system depressant with a narrow recreational dose window and analytical detection time. We describe data relating to intoxicated patients presenting to emergency departments across metropolitan Adelaide who tested positive for gamma-hydroxybutyrate. This work was part of the Emergency Department Admission Blood Psychoactive Testing study. METHODS: Over a 15-month period, patients presenting to four metropolitan emergency departments with symptoms of drug intoxication were enrolled in the study. The methodology involved the collection of demographic and clinical data and a de-identified blood sample which underwent comprehensive toxicological analysis. Gamma-hydroxybutyrate was determined using an acid-catalysed cyclisation followed by liquid-liquid extraction and gas chromatography-mass spectrometry. Data relating to samples positive for gamma-hydroxybutyrate were examined. RESULTS AND DISCUSSION: A total of 1120 patients were enrolled between March 2019 and May 2020, 309 of whom were positive for gamma-hydroxybutyrate (27.6%). Of these, 256 (83%) were also positive for metamfetamine (methamphetamine). The most common clinical observation in gamma-hydroxybutyrate-positive patients was central nervous system depression (89%). There was a significant relationship between gamma-hydroxybutyrate status and sex; although males outnumbered females in absolute terms, a higher proportion of females (32%) tested positive for gamma-hydroxybutyrate than males (25%, P = 0.0155). Blood gamma-hydroxybutyrate concentrations ranged from 10 to 651 mg/L (0.096-6.2 mmol/L) and increasing gamma-hydroxybutyrate concentration correlated with severe toxicity. The presence of gamma-hydroxybutyrate had a significant impact on the patient discharge destination: the majority (69.2%) of gamma-hydroxybutyrate-positive patients were managed and discharged from the emergency department or their attached short stay wards. A significantly higher proportion of gamma-hydroxybutyrate-positive patients were admitted to the intensive care unit (28.2%) compared with gamma-hydroxybutyrate-negative patients (12.7%, chi-squared = 36.85, P <0 .001). Gamma-hydroxybutyrate positive cases accounted for 45.8% of all study-related intensive care unit admissions. CONCLUSIONS: Gamma-hydroxybutyrate is commonly detected in illicit drug-related emergency department presentations and is detected disproportionately in the patient cohort who require intensive care unit level care.

Establishing the protocols for the South Australian Emergency Department Admission Blood Psychoactive Testing (EDABPT) programme for drug surveillance.

OBJECTIVE: ED presentations because of illicit use of psychotropic drugs and pharmaceuticals result in significant medical harm and resource consumption. Patient assessment is complicated by the regular emergence of new psychoactive substances, difficulties associated with their identification and a lack of information about their effects. Here we report the protocol for the Emergency Department Admission Blood Psychoactive Testing (EDABPT) programme, an observational study utilising clinical data capture and definitive drug identification to assess the medical impact and patterns of illicit drug use in the community, and their geographic and temporal fluctuations. The study provides data to an early warning system targeting an improved public health response to emerging drugs of concern. METHODS: Enrolment of adult patients presenting with suspected illicit drug use occurs at four major EDs in a single urban setting. Clinical and demographic data are collected by treating clinicians. Blood samples are collected at presentation and frozen on site prior to transport to a specialised forensic facility for comprehensive toxicological screening. RESULTS: Results are fed back to clinicians and disseminated more broadly via an existing local early warning system. Targeted warnings and public health releases are instigated where heightened risk or harm is identified. CONCLUSION: The study pairs city-wide patient enrolment with analytically confirmed toxicology results to allow broad sampling and identification of illicit drugs causing medical harm. It provides a mechanism for the identification of new agents as they emerge in the community, delivers a relevant and reliable source of information for public health agencies and clinicians and supplements existing local early warning mechanisms.