Proceedings of the Toxicology and Poisons Network Australasia (TAPNA) 2023 Annual Scientific Meeting

Arsenicals induce their toxic effects by binding to sulfhydryl groups in multiple enzyme systems, inhibiting metabolism and disrupting oxidative phosphorylation generating reactive oxygen species. In animal studies NAC has been shown to decrease arsenic mediated oxidative damage and in in vitro studies NAC was shown to chelate arsenic. The optimal time to commence NAC therapy has not been studied, but animal studies have shown earlier treatment improved survival. Given its favourable safety profile, low cost and the findings from animal studies, NAC should be used as an adjunct to standard chelation therapy in arsenic poisoning. Further investigation is required to establish the optimal duration of treatment and dosing.


Introduction
Nitrous oxide (N2O) inactivates vitamin B12 which reduces recycling of homocysteine to methionine.Subsequently, methionine deficiency can impact myelin repair and sensorimotor neuropathy ensues.An elevated homocysteine concentration can be used as a metabolic biomarker in the assessment of vitamin B12 deficiency associated with nitrous oxide abuse.Its relationship with neurological recovery in treated patients is not well characterised.

Case summary
A 22-year old non-pregnant female described progressive upper and lower extremity paraesthesia, impaired gait and frequent falls over 1-2 weeks.She had a 2-year history of nitrous oxide abuse with short periods of abstinence.Over the preceding 2 months, she had used 100-150 N2O bulbs daily.No other regular substance use including alcohol was described.On examination, she had symmetrically reduced fine touch from C7 spinal level below, reduced proprioception at finger joints, dysmetria and a broad-based, high stepping ataxic gait associated with bilateral foot drop.
Macrocytosis with no myelosuppression and a low Vitamin B12 concentration was detected (holotranscobalamin 29 pmol/L (reference range 25-165), vitamin B12 < 74 pmol/L (reference range 156-698), homocysteine 104.4 micromol/L (reference range 5-15)).MRI brain and whole spine demonstrated symmetric bilateral intramedullary high T2/STIR signal within the cervical dorsal columns (inverted V sign) extending from the level of C2 to C7 consistent with subacute combined degeneration of the spinal cord.
She was treated with daily IM 1 mg vitamin B12 supplementation and oral methionine 1 g three times a day for 2 weeks, then a staggered dose of IM 1 mg vitamin B12 over 6 months.She received multidisciplinary care involving neurology, psychology, drug and alcohol counselling and an intensive rehabilitation program.

Discussion
Restoration of homocysteine concentrations to reference intervals does not correlate with timing of neurological improvement but may guide dose and duration of vitamin B12 supplementation.recommendations on the assessment and management of poisoned patients at risk for QT interval prolongation are generally lacking.The clinical cases QT working group is aiming to release recommendations for particular drugs of concern taken in overdose.
The first group of reviewed drugs are the antipsychotic medication group, which is often referenced as a high risk group of drugs for developing QT interval prolongation.They are also a group of drugs that commonly cause tachycardia in overdose, along with a prolonged QTc.This presentation will touch on the evidence, or often lack of documented evidence, for QT changes in antipsychotic drugs, and the recommended approach for monitoring.

Background/objective
Amygdalin is an aromatic cyanogenic glycoside compound found in the kernels of various fruits and plants.Amygdalin exists within the Complementary and Alternative Medicine (CAM) industry and is marketed under Amygdalin, Vitamin B17 or Laetrile.Oral and parenteral formulations are available.However, it is considered a substance of such danger to health as to warrant prohibition of sale, supply and use in Australia (Schedule 10).The main use of amygdalin within the CAM industry is cancer therapy, despite no evidence to support its curative effects in cancer and its significant side effect profile of cyanide toxicity and death.We aimed to measure the number of calls received by the New South Wales Poisons Information Centre (NSW PIC) regarding Amygdalin exposures.

Methods
We performed a retrospective review of all amygdalin/cyanogenic glycosides product ingestion exposure calls to the NSW PIC between January 1st 2015 and December 31st 2022.Terms searched included amygdalin, B17, cyanide, apricot and ingestion.
Inhalation cyanide exposure in the setting of fire was excluded.

Results
There were a total of 159 calls to NSW PIC resulting in 129 unique exposure calls once duplicate entries and repeat calls regarding the same case were removed.82 (64%) calls were minor exposures who were advised to stay at home, whilst 47 (36%) calls had either a significant history, symptoms to prompt referral to hospital or were a call for advice from a treating hospital clinician.Of the 47 calls in or referred to hospital, 15 (12%) involved using cyanogenic glycosides as a method of suicide.3 of these cases used excessive apricots or berries, whilst the remaining 12 used cyanide tablets, powder, liquid or amygdalin pills.

Discussion
This study identifies that a significant burden of concern is generated from the misuse of amygdalin/ cyanogenic glycoside products for cancer prevention and treatment.Additionally, significant toxicity can occur unintentionally requiring hospital admission.There is evidence of ongoing supply, use and harms from illicit amygdalin/B17 products which carry the risk of serious toxicity.Poisons centre data can contribute to ongoing surveillance and control of this public health threat.

Background
Non-fatal self-harm is a strong risk factor for completed suicide and has been associated with excess mortality from natural and unnatural causes.This study aimed to examine premature death after self-poisoning in NSW, Australia.

Methods
This study uses the Poisoning And enVenomation Linkage to evaluate Outcomes and clinical Variation in Australia (PAVLOVA) cohort.PAVLOVA is a longitudinal linkage of poisonings in NSW, 2011-2020.The present study uses Admitted Patient Data Collection (APDC) data linked with deaths data.Individuals were followed up from their first intentional poisoning event in the dataset.For all individuals in the APDC with a non-fatal intentional poisoning event, we examined cause-specific mortality to calculate standardised mortality ratios (SMRs) using reference data from the Australian Institute of Health and Welfare.We also estimated years of life lost (YLL) based on Australian Bureau of Statistics life tables.

Discussion
Life expectancy is reduced in people who self-poison.In part this is due to the known association between non-fatal self-harm and suicide.The increased risk of death from natural causes underscores the need to also focus on physical needs and health inequalities in people who self-poison.Mechanisms that could explain this gap include high rates of substance misuse in this cohort, and societal factors including economic disadvantage.

Background
The increasing burden of disease from poisoning in Australia highlights the need to better understand the epidemiology and outcomes of poisoning/envenomation and severe adverse drug reactions (ADRs).To study this, we established a state-wide poisoning data linkage cohort in New South Wales (NSW).

Methods
Poisoning And enVenomation Linkage to evaluate Outcomes and clinical Variation in Australia (PAVLOVA) is a longitudinal linkage of records relating to poisoning, 2011-2020.It contains the following datasets: NSW Ambulance, Emergency Department Data Collection (EDDC), Admitted Patient Data Collection (APDC), Cause of Death Unit Record File (COD-URF)/Registry of Births Deaths and Marriages (RBDM), and a NSW Toxicology dataset (NSW Poisons Centre and data from 4 toxicology units).Main outcome measures include poisoning events by intent, substances involved, demographics, and geographic location.Here we focus mainly on APDC hospitalisations to provide a cohort profile.

Results
Across all datasets, there were 612,502 people with at least one event (poisoning, envenomation, or ADR).Mortality data revealed 7784 poisoning deaths, median age 53.In the APDC, there were 626,781 events (involving 450,184 individuals), most commonly ADRs (n = 561,984 events), intentional poisonings (n = 72,982), accidental poisonings (n = 39,718), and animal/plant exposures (n = 11,568, numbers add to >100% as each event can have multiple categories involved).The median age for admitted patients was 65 years, 54% female [accidental poisoning (median 46 years, 48% female), intentional poisoning (33 years, 62% female), envenomation (37 years, 34% female), and ADRs (69 years, 54% female)].Regional and remote areas were over-represented.The most common substances involved in poisoning were paracetamol and benzodiazepines.Substance use disorders were documented for 72% of those hospitalised with an intentional poisoning, and 57% of those hospitalised with an accidental poisoning.Adolescent females had the highest rate of intentional poisoning, while accidental poisoning had a bimodal distribution, highest in children <5 and males aged 20 to 50.

Introduction
Alkyl nitrites or "poppers" are short-acting vasodilators and potent oxidizers that are inhalationally used for their purported effects of euphoria, muscle relaxation, and sexual enhancement.They are often sold as "VHS cleaner" or "leather cleaner" and packaged in small, colourful bottles.Methaemoglobinemia is a well-documented complication of nitrite exposure.We report two cases significant methaemoglobinemia after ingesting alkyl nitrites that were mistaken as energy drinks.

Case 1
A 66-year-old male presented to the emergency department (ED) complaining of dyspnoea after drinking a "5-Hour Energy™ drink" several hours prior.The patient identified the product as "RUSH", an isobutyl nitrite solution.His initial vital signs were: Blood Pressure (BP) 70/40 mmHg; Heart Rate (HR), 56 beats/minute; Respiratory Rate (RR), 16 breaths/ minute; Oxygen Saturation, 79% (room air).Acrocyanosis was noted on physical examination.Venous blood gas testing revealed a methaemoglobin concentration of 42.7%.After consultation with the regional poison centre, the medical team administered 2 mg/kg of intravenous (IV) methylene blue (MB).The patient quickly improved; a repeat methaemoglobin concentration was 3%.After brief observation, he had no recrudescence of methaemoglobinemia and was discharged home.

Case 2
A 58-year-old male was brought to the ED for obtundation after a syncopal event.His initial vital signs were BP, 93/62 mmHg; HR, 112 beats/minute; RR, 24 breaths/ minute; Oxygen Saturation, 85% (room air).He was endotracheally intubated for "respiratory distress." His methaemoglobin concentration was 68%.He received 200 mg IV MB.After extubation the following day, he reported consuming a bottle of "RUSH" (isobutyl nitrite) instead of a "5-Hour Energy™" drink.He was discharged home the same day without further sequelae.

Discussion
Despite recent changes in alkyl nitrite scheduling in Australia, they are still available with brightly coloured labelling resembling commercial energy drinks such as 5-Hour Energy™.Consumers of energy drinks, alkyl nitrite enthusiasts, clinical practitioners, and specialists in poisons information and should be aware of the combination of similar packaging and unintended methods of alkyl nitrite exposure may lead to life-threatening methaemoglobinemia.

Background
Patients presenting with deliberate self-poisoning may also have a coexistent substance use disorder (SUD).
Identification of SUD is important as there is evidence of benefit from both brief and complex interventions.Poisons Information Centre (PIC) may have a role in identifying patients with SUD using screening questions.This study examined whether it was feasible to ask screening questions as part of normal practice.

Methods
A multidisciplinary group developed two questions for Specialists in Poisons Information (SPIs) to ask hospital callers during a telephone consultation for patients with deliberate self-poisoning.The PIC database did not prompt the SPIs to ask the questions.The 2 questions were intended to have a higher sensitivity than specificity.
Q1: Do you know if the patient had consumed alcohol or other substances at the time of the overdose?
Q2: And are you aware of any other substance use problems?For example, in the past week.
The outcomes were whether the questions were asked and the recorded response to the question (yes, no, unknown)

Results
In the study period (4/11/22 to 12/12/22) there were 935 consecutive eligible unique calls.Questions were asked in 437 (46.7%) calls.Of these 163 (37.2%) patients had consumed alcohol or other substances at the time of presentation (Q1).Awareness of the caller to prior or current substance use was identified in 95 (21.7%) patients.67 of these 95 patients were positive for question 1.
In the group not asked the questions (n = 498) the data record was reviewed, and 110 patients were identified who were likely to have satisfied Q1 on the basis of the ingestion history.Alcohol was listed in 75 of these patients.SPIs fed back that some callers questioned the relevance of these questions to clinical management which was readily addressed in SPI training sessions.

Discussion
Delivery of questions related to SUD for use by SPIs is feasible.It is likely that more formal prompting at the point of data entry would increase the implementation.The screening question indicated a high prevalence of substance use and suggest a high rate of SUD in patients presenting with deliberate self-harm.

Introduction
Arsenic exposure typically results in gastrointestinal and cardiovascular toxicity.Respiratory, renal and liver toxicity can also occur.We present a case of acute arsenic toxicity treated with 2,3-dimercaptopropane sulfonic acid (DMPS) and N-acetylcysteine (NAC).

Case
A 53-year-old male patient presented to a regional hospital 2 hours post ingestion of an unknown quantity of Coopers Instant Wetting Powder Sheep Dip (66% arsenic trioxide, 23% sulphur and 0.42% rotenone), mixed in 600mL water.
On arrival the patient had vomiting and diarrhoea.ECG and venous blood gases were normal, no radio-opaque material was identified on chest or abdominal radiographs.Seven hours post ingestion hypotension developed (BP 90/60).Intravenous fluids were commenced.
He was commenced on 5 mg/kg DMPS every 6 hours.A NAC infusion was commenced (as for paracetamol poisoning) and continued for 48 hours.After 5 days DMPS was ceased and dimercaptosuccinic acid (DMSA) continued at 500 mg twice daily for 14 days.He was asymptomatic on discharge without peripheral neuropathy or bone marrow suppression.

Discussion
Acute arsenical toxicity can be life-threatening and aggressive treatment is mandatory.Animal data have shown that in acute arsenic intoxication the efficacy of chelation is greatest when administered promptly.

Introduction
Drug adulteration and substitution involves the addition of bulking agents or substances to enhance or mimic a drug effect.Over the past 15 years, substitution of illicit drugs with novel psychoactive substances (NPS) has become increasingly common and poses significant risks to users if they are unaware of the substitution.Historically ketamine was not adulterated and was often diverted from legitimate sources.Recently, adulteration has been reported.
The Emerging Drug Network Australia (Victoria) (EDNAV) is a collaborative project to detect illicit novel drug exposures in patients presenting to Victorian Emergency Departments, involving analytical confirmation of exposure.EDNAV was designed to facilitate the release of early warnings to the general public.

Case 1
A 24-year-old male presented after insufflating 1 gram of white powder sold as "ketamine".He had an altered conscious state (GCS 13/15), with periods of catatonia.He recovered with supportive care.

Case 2
A 27-year-old male was found with an altered conscious state (GCS 9/15) with severe agitation, after insufflation of white powder sold as "ketamine".He recovered with supportive care.

Case 3
A 17-year-old female was found with an altered conscious state (GCS 9/15) following insufflation of cocaine and white powder sold as "ketamine".She had a prolonged altered conscious state requiring ICU admission, and subsequently became agitated requiring chemical and physical restraint.
3-hydroxyphencyclidine (3-HO-PCP) was detected in all cases.Prescription medications and other illicit substances were also detected in all three cases.

Discussion
3-HO-PCP, a NPS, is a structural analogue of phencyclidine (PCP).Reports of recreational use date from 2009.Like PCP, 3-HO-PCP is a potent NMDA receptor antagonist.However, in animal studies 3-HO-PCP has also been shown to have mu-opioid receptor agonism.
3-HO-PCP produces dose-dependent dissociative anaesthesia, hallucinogenic and euphoric effects.Onset of effects can take up to 60 minutes (versus 10-20 minutes with ketamine), with users reporting more potent effects than ketamine or PCP.Individuals who unknowingly use 3-HO-PCP-substitued ketamine are at risk of re-dosing and developing severe toxicity.Accordingly, a drug alert was released by the Department of Health in Victoria in November 2022.

Introduction
Thiocyanate poisoning is a rare cause of neurotoxicity and chloride assay interference.We present a case of thiocyanate poisoning diagnosed in the absence of history using chloride measurements, and successful treatment with dialysis.

Case Summary
A 54 year old male was brought to a rural hospital in a state of agitated delirium and hypotension.He was found to be hyperglycaemic with raised ketones, and was treated for suspected encephalitis with sedation, intravenous antibiotics, fluid resuscitation, insulin infusion and electrolyte replacement.Despite improvement of haemodynamic parameters, clearance of blood ketones and normal neuroimaging, the patient was intubated for ongoing agitated delirium and was transferred to a regional intensive care unit for ongoing management.
Advice was sought from the Poisons Information Centre on day two of presentation due to ongoing delirium and profound electrolyte derangements on daily laboratory testing; notably an unrecordably high serum chloride concentrations (>200mmol/L [RR 95-100 mmol/L]) and low ionised calcium of 0.07 mmol/L [RR 1.15-1.32mmol/L].
History revealed the patient had access to a school science laboratory, and given the electrolyte derangements and clinical presentation consistent with thiocyanate toxicity, treatment with dialysis was recommended.Thiocyanate concentrations later returned confirming the diagnosis, and dialysis was continued until thiocyanate concentrations returned into the normal range.The patient's neurological status improved with clearance of thiocyanate and was extubated with on day four of presentation.The patient later confirmed intentional ingestion of potassium thiocyanate with suicidal intent.

Discussion
Thiocyanate poisoning presents with neurologic toxicity and interferes with chloride assays depending on the type of analyser in use.Haemodialysis appears to improve clearance of thiocyanate and clinical effects.Occult poisonings should be considered where profound electrolyte derangements are recorded.

Introduction
Pregabalin is a GABA agonist which can cause coma in overdose, particularly if co-ingested with opioids or benzodiazepines.It has rising recreational misuse in Australia and is included as a monitored medicine on the QScript Real Time Prescription Monitoring System.QScript became mandatory to check before prescribing monitored medications in Queensland on 28th October 2021.

Methods
This is a retrospective review of pregabalin-related presentations to the Princess Alexandra Hospital Clinical Toxicology unit in the four years before (November 2017-October 2021) and one year after (November 2021-October 2022) the introduction of QScript Real Time Prescription Monitoring System throughout Queensland.Patients were identified through the unit database and medical records were reviewed.Data relating to demographics, exposure details, clinical features, management, and disposition were extracted.

Conclusion
The introduction of mandatory QScript review prior to prescribing monitored medications was associated with a reduction in pregabalin-related poisoning presentations.Patients were less likely to have pregabalin as a prescribed medication suggesting less access.The severity of poisoning was similar in both periods.

Background
Staff from disability group homes (also known as community residential units) often call poisons information centres (PICs) for advice.

Aim
To describe the frequency, type and timing of PIC calls from group homes in Victoria, with a focus on calls about medication incidents.

Methods
A retrospective audit of calls received from group homes in Victoria over a three-month period (October to December 2021) was conducted.Calls were analysed for type of exposure, substance and time of day.

Conclusions
Calls to PIC from group homes were common.Most calls were about medication incidents.Many calls were unrelated to poisoning (e.g.missed and refused medication doses, medication queries), and thus arguably outside of the core business of PICs.Majority of medication-related calls were received outside of business hours, which may reflect poor access to GPs and community pharmacists after-hours.These data suggest that PICs are filling a gap in care provision for residents of disability group homes.

Background
Paracetamol poisoning, the most common poisoning-related presentation to Australian emergency departments, can result in severe acute liver injury and death.It is unclear whether cases of suspected paracetamol poisoning are being managed in accordance with national guidelines.

Methods
Patients presenting to the Southern Adelaide Local Health Network, including Flinders Medical Centre, a large tertiary hospital, and Noarlunga Hospital, a community hospital, with a detectable paracetamol level were identified over a six-month period (15/6/22 to 15/12/22) from the electronic medical record.The medical records were reviewed to assess the consistency of management with national guidelines [1].This was a quality improvement project and received an ethics exemption.

Results
This is an interim analysis of the two-week period between 15/6/2022 and 29/6/2022.Ten patients were identified as having paracetamol poisoning.The mean age was 33.3 years (standard deviation 12.6 years) and most were male (n = 8, 80%).The mean dose of paracetamol taken was 14.4 g (standard deviation 15.7 g, range 1.5-50 g) with the time from poisoning to presentation being 4.9 hours (standard deviation 1.6 hours, range 3-7 hours).Seven of the 10 patients reported the ingestion time as a range and three of the 10 had an uncertain poisoning dose.For two patients the weight was not documented in the medical record.No patients received activated charcoal and three patients received N-acetylcysteine.The national guidelines were adhered to in seven of the 10 patients.There were two patients that were likely managed in accordance with the guideline although there was no documented weight or ingestion time to confirm this.There was one instance of nonadherence due to the lack of a paracetamol level being taken eight hours after a modified release poisoning although this would not have changed management.

Conclusion
Paracetamol poisoning is generally being managed in accordance with national guidelines in our local health network.There were often uncertainties in the time of ingestion.Education is needed on the conservative application of these guidelines using the earliest possible ingestion time as well the need to measure the weight and repeat blood tests at the recommended intervals.

Introduction
Aspiration pneumonitis is an important complication of overdose that can greatly increase morbidity and mortality.There is limited evidence on the topic although risk factors like older age, GCS <15, seizure and tricyclic antidepressants have been previously identified.We aim to describe presentations to a clinical toxicology unit that develop aspiration pneumonitis.

Methods
This is a retrospective series of poisoning presentations to a clinical toxicology unit from January 2015 to December 2021.Presentations were identified though the unit database and patient electronic medical records were reviewed, those with radiographic evidence of aspiration were included.Demographic data, clinical features, investigations, treatment, and disposition were extracted.

Conclusion
Aspiration is rare in poisoned patients and the vast majority occur prior to presentation to hospital.The most common class of agents responsible are opioids and benzodiazepines.

Introduction
Stonefish envenomation results in localised severe pain and swelling as well as systemic features including vomiting, arrhythmia, pulmonary oedema and rarely death.Antivenom is available, although there are limited data regarding effectiveness.The aim of this series is to characterise presentations of patients with suspected stonefish envenomation and investigate treatments including antivenom.

Methods
This is a retrospective observational series of suspected stonefish envenomation as reported to Queensland Poisons Information Centre (QPIC) or Princess Alexandra Hospital Clinical Toxicology Unit (PAH CTU) from July 2015 to January 2023.Patients were identified through both units' databases.Data on clinical features, investigations and treatment were collected from the patient's electronic medical record.

Results
There was a total of 88 suspected stonefish envenomations over the period.The median age was 26 (range: 5-69 years) and 71 (80%) patients were male.Exposures were to the foot in 52 (59%), hand in 30 (34%) and not documented in six patients.Pain was reported in 86 (98%) with a median peak pain score of 10 (range 4-12).A clear wound was documented in 65 (74%), with local swelling in 64 (73%).A retained foreign body occurred in eight (9%) presentations.Systemic symptoms were rare with vomiting occurring in four (5%) patients and dizziness in two (2%).There were no instances of hypotension, arrhythmia, or pulmonary oedema.Hot water immersion was used in 72 (82%) presentations.Oral analgesia was given in 72 (82%) presentations, most commonly paracetamol.Parenteral analgesia was given in 77 (88%) presentations most commonly opioids.Local anaesthetic block was performed in 18 presentations (10%) and was documented to be effective in 16/18 (89%).Five patients received antivenom for intractable pain, all received further analgesia, either parenteral opioids, ketamine, or local anaesthetic block.

Conclusions
Stonefish envenomation is characterised by severe pain.Systemic symptoms were rare and not severe in this series.Local anaesthetic block appeared to be the most effective intervention for severe pain when performed.Antivenom appeared to be ineffective for severe pain.

Introduction
Aerosol abuse, or inhalant abuse, involves inhaling chemicals from common household items; this is a significant issue amongst young people in particular.[1,2].We report a case of hydrocarbon inhalation with cardiac arrest and associated complications.

Case summary
A 19 year old male was found unresponsive by his mother, with two empty cans of Rexona deodorant and a towel with white residue nearby.Family members initiated CPR.Upon arrival of paramedics, he was found to be in ventricular fibrillation and required 14 minutes of CPR along with 2mg IV adrenaline, 300mg IV amiodarone and 5 defibrillation attempts to achieve return of spontaneous circulation (ROSC).He was transported to a tertiary hospital, where he was intubated and transferred to ICU for ongoing care.
Despite being initially stable, he developed cardiogenic shock 6 hours later, with echocardiogram showing marked LV apical hypokinesis and LVEF 30%, consistent with Takotsubo cardiomyopathy.He was treated with IV dobutamine infusion for 2 days.Repeat TTE, CTCA and cardiac MRI were normal.
He was extubated 2 days later but had marked neurological impairment with severe intermittent agitation.This was managed with IV dexmedetomidine, diazepam and olanzapine.The agitation is thought to be secondary to hydrocarbon toxicity and not hypoxic encephalopathy as MRI brain showed no evidence of hypoxic or ischaemic injury.EEG showed global encephalopathy consistent with sedating medications.
Chest radiograph & chest CT scan showed diffuse scattered ground glass opacities, consistent with chemical pneumonitis.Aspiration was considered and excluded as a cause.The patient's high flow oxygen requirement improved after 8 days.His neurological state improved gradually and he was discharged from hospital after 17 days.

Discussion
This case highlights potential severe complications of hydrocarbon toxicity including cardiac arrest, Takotsubo cardiomyopathy, hydrocarbon induced encephalopathy and chemical pneumonitis, all of which were potentially reversible if managed rapidly and appropriately.

Background
Guanfacine is a centrally acting alpha-2 adrenergic receptor agonist approved for the treatment of hypertension and attention deficit hyperactivity disorder (ADHD).Guanfacine use has been increasing since 2009, when it was approved for use in ADHD [1].It is structurally similar to clonidine with a longer duration of action and favourable side effect profile.Despite its widespread use, there is limited information is available on the clinical presentation and outcome of guanfacine overdose.

Objective
The purpose of this study was to evaluate and describe the clinical presentation and outcomes of patients with reported guanfacine overdose who were referred to the South East Area Toxicology Service (SEATS) over a 2 year period.

Methods
This retrospective case series includes all patients who were referred to the SEATS with a reported overdose of guanfacine between February 2020 and December 2022.Data were supplemented with a manual search of patients' electronic medical records.Demographic information, dose, co-ingestants, clinical presentation, complications, management and time to discharge were recorded and analysed.

Results
A total of 13 patients with guanfacine overdose were identified within this time period.The median patient age was 11 years (range: 6-19 years).Co-ingestants were reported in 7/13 (53.85%) patients.Bradycardia and drowsiness were reported in 7 (53.9%)and 2 (15.4%) patients respectively.Hypotension (SBP <90mm Hg) was noted in 1/13 (7.69%) patient.No patients required interventions for bradycardia, hypotension or drowsiness.All patients were managed with supportive care and discharged after a median of 12 hours (range 8-73 hours).No patient had any significant adverse event related to the guanfacine overdose.

Conclusions
Guanfacine overdose typically presents with bradycardia and mild drowsiness.However, the majority of patients can be managed with supportive care and do not require intervention.Further studies are required to better understand the clinical presentation, optimal observation period and outcomes of patients.

Methods
Patients who were administered naloxone but no opioid (to exclude iatrogenic overdoses) by ambulance staff were extracted from the 2017 to 2021 St John Ambulance and 2018-2021 Wellington Free Ambulance electronic records and de-identified.Together these cover all land ambulance services for New Zealand.Annual rates of patients given naloxone were determined, as well as patient demographics (age, gender), attendance scene area type and level of deprivation.Total naloxone dose per patient and route(s) of administration, changes in Glasgow Coma Scale (GCS) and respiratory rate from initial to last observation, and treatment and transport times were summarised by medians and inter-quartile ranges (IQR).

Discussion
Annual rates of New Zealand land ambulance naloxone administrations were determined and can serve as a comparison point for future public health surveillance of opioid harm.A significant limitation is that suspected opioid intoxications were not independently verified.

Background
Toxicology as a subspecialty in Australia is in its relative infancy.The first dedicated clinical toxicology unit (CTU) was founded in Newcastle in 1986 and since this time there have been several CTU established across Australia.Within these units the role of doctors specialising in clinical toxicology is well established.However, the role of subspecialised nurses remains to be defined.The Princess Alexandra Hospital developed a course to train senior nursing staff in clinical toxicology with view to support a nurse practitioner role in clinical toxicology.The aim of this study is to observe the activity of a nurse practitioner (NP) candidate in clinical toxicology to determine their role within a CTU.

Methods
This is an observational study of a toxicology NP candidate's role within the CTU at the Princess Alexandra Hospital.Data from their training logbook over the 6-month period (June 2022 -November 2022) were extracted to describe episodes of care and other work duties including research and education.

Results
Over the 6-month period the NP candidate working in an 0.5 full-time equivalent capacity was involved in 315 episodes of patient care.They attended 54 consultant ward rounds, where they participated in gaining risk assessment, patient examination and clerking in the electronic medical record.In addition to the 207 patients reviewed on ward rounds, they reviewed and managed 108 patients as the treating clinician, with the support of the clinical toxicologist for advice.The toxicology NP candidate participated in research within the unit in randomising patients for trials, obtaining consent and collecting data.They performed three formal education days for nursing staff on topics of risk assessment, decontamination, antidotes, ECG, toxidromes and paracetamol poisoning.It appeared that the NP candidate successfully completed a similar scope of practice to the rotational registrar appointed to the unit.

Conclusion
A toxicology NP appears to be a viable clinical role.With the increasing demand for dedicated toxicological expertise, consideration could be given to expanding nursing subspecialisation in toxicology.

Cairns Hospital, Trinity Beach, Australia
Since Sutherland's Lancet publication showing retardation of tiger snake venom in monkeys, Pressure bandage immobilisation (PBI) has become the recommended first aid in Australia and Papua-New Guinea.Yet we see cases in which skill retention and performance is poor, the pressure is not maintained, and victims are envenomed despite prompt and effective PBI.However, the attitude has been "it may do some good, and does not cause harm" We present 2 cases managed in Cairns in which snakebite patients had PBI applied and suffered harm as a result of the PBI.We will ask the question, "Do we need to rethink first aid for snakebites?"

Introduction
Western Australia (WA) has had the highest prevalence of methamphetamine (ice, crystal meth) use in the country over the past decade.Many patients are seen in the emergency department with presumed methamphetamine intoxication or drug-induced psychosis without analytical confirmation.Little is known regarding the concentration of methamphetamine in the blood of these patients and how this relates to the clinical effects for the patient.

Methods
The Western Australian Illicit Substance Evaluation (WISE) study enrolled participants believed by their treating clinician to be intoxicated with illicit stimulant, hallucinogenic or cannabinoid drugs and who required IV access or blood tests for clinical care.A research blood sample was taken on patient arrival and details of patient history, examination and interventions were collected by clinical and research staff.Toxicological examination of biological samples used liquid chromatography-mass spectrometry techniques including Quadrupole Time of Flight (QTOF) screening and Triple Quadrupole (QQQ) targeted analyses.

Discussion
Methamphetamine was by far the dominant drug detected in the WISE study.Most patients were managed and discharged home from within the emergency department or the observation ward.The median methylamphetamine level was quite low.Prolonged or repetitive exposure to the drug, combined with lack of sleep, may contribute to the severity of symptoms rather than acute drug toxicity.

Introduction
Malaysia is surrounded with coasts and seas with a wealth of marine biodiversity, ecosystems, habitats and other natural resources.MNPC received cases from time to time related to marine animal envenomation and poisoning however data regarding this subject are minimal.This study aims to report the number of marine animal envenomation and poisoning referred to MNPC to be a foundation for other studies related to this subject.

Methods
Retrospective study using data from all referred cases to MNPC from year 2006 till 2021 and analysed by Microsoft Excel.

Introduction
Children spend a large amount of time at school, and while attending, are potentially at risk of poisoning.This study follows a previous New Zealand National Poisons Centre (NZNPC) investigation covering 1989-2009, updating data on childhood exposures occurring in schools for the most recent 10 years, to determine trends and suggest harm minimization strategies.

Methods
A retrospective analysis of exposures reported to the NZNPC from preschool, primary and secondary schools between January 1, 2010, and December 31, 2019, was undertaken.Students aged 0 to 19 years old were included, while staff were excluded.The number of calls and patients, patient age, school type, reason for exposure, substance, and disposition advice were collated and analysed.

Results
There were 3389 calls involving 4151 patients exposed to 4736 substances that met the study criteria.Call numbers increased with 356 exposures in 2010 and 608 in 2019.Three and four year-olds, followed by 13 and 14 year-olds were the most exposed age groups.The predominant reason for exposure in primary and preschools was child exploratory (57% and 90% respectively) and in secondary schools, unintentional (68%).Secondary schools accounted for 90% of intentional and 84% of abuse exposures.In primary and preschools, plant exposures (26.6% and 25.65% respectively) and miscellaneous chemicals (28.1% and 20.3% respectively) were the commonest substances involved.Secondary school exposures most commonly involved miscellaneous chemicals (31.8%), and therapeutic simple analgesics (9%).78% of all patients did not require medical treatment.

Discussion
Call volumes showed an upward trend since 2016 with the number of school exposures almost doubling since 2010.Younger students were more commonly exposed to plants, while secondary school students were more likely to be exposed to miscellaneous chemicals and therapeutic simple analgesics.Reasons underlying exposures seem congruent with developmental age, with younger children exploring their local environment and secondary students accounting for nearly all intentional and abuse exposures.Education programs about the dangers of substance abuse and harm minimization could be beneficial for secondary school students.The majority of exposures did not require medical attention suggesting school exposures are generally of low risk overall.

Background
Cognitive aid have been used in the aviation industry for decades to minimise human error and facilitate communication.In medicine, cognitive aid and checklists have emerged.Examples have ranged from procedural checklists, care bundles or most notably to facilitate perioperative safety with the WHO surgical safety checklist.Cognitive aids are also found across critical care specialties to support clinicians during critical procedures (e.g.pre-intubation checklists) or during crisis management (e.g.advanced life support (ALS)).Specific aids exist to address high acuity, low occurrence (HALO) events relevant to toxicology, for example local anaesthetic toxicity.

Methods
A quality improvement project in Liverpool ED was undertaken to develop a cognitive aid to support the management of severe hyperthermia, a HALO event.This clinical scenario demands rapid, focussed resuscitative care where the priorities may deviate from standard ALS protocols.While the cognitive aid emphasises the importance of early expert consultation, the project aimed to guide early resuscitation in the crucial first minutes.The card was designed based on identified core clinical priorities in early care including immediate resuscitation goals and prioritisation of early advice with provided contact numbers.Suggested role allocation and therapeutic prompts are intended to empower staff and encourage effective communication and teamwork.Overall, there is an emphasis on patient and provider safety.
We tested the cognitive aid in the simulation laboratory, and feedback was sought from both medical and nursing staff.A final test of the cognitive aid was conducted via in situ simulation in the department.While acknowledging the Hawthorne effect of change in performance amongst observed participants, all aspects of the cognitive aid were achieved in real time within the desired time scale.

Conclusion
Clear cognitive aids may assist in prioritising aspects of resuscitation and reduce human error, particularly in HALO events.They may be of value to a poisons centre in providing focused time points and priorities to the treating team in a hospital.

Introduction
Mirtazapine is typically associated only with sedation in overdose.We present a case of anticholinergic delirium following a large mirtazapine overdose that had a good clinical response to physostigmine.

Case summary
A 41-year-old male arrived in the Emergency Department (ED) at 1030hr, having been found unresponsive at home at 0830hr.He was reported to have taken 90 tablets ×15mg (1350mg) mirtazapine with 700mls whisky (40% ABV).His only history was depression and alcohol use disorder but no other substance misuse.
On arrival, GCS was 10 (E3M2V5) but without respiratory compromise.His vital signs showed he was afebrile, a mild tachycardia (110BPM) and mild hypertension (SBP 140mmHg).There was evidence of nystagmus and transient inducible ankle clonus with normal tone.ECG showed both normal QRS and QT intervals.
Over the next 3hrs, he developed psychomotor agitation.He began plucking at the air and mumbling incomprehensibly.A low-grade pyrexia was noted (37.8 °C).Initial attempts to manage his agitation with parenteral benzodiazepines and olanzapine were unsuccessful, requiring mechanical restraint.A bladder scan demonstrated 600 mL of urine present requiring catheterisation.
Given ongoing agitated delirium, he was given 0.5 mg of physostigmine over 10 minutes with rapid improvement.A further dose was given with recovery to GCS 15, allowing removal of restraints and the ability for the patient to clearly verbalise and confirm the history of ingestion.

Discussion
Mirtazapine, an antidepressant, that blocks central α2 receptors, promoting noradrenergic and serotonergic neurotransmission has been reported to be relatively benign in overdose [1].Clinical features reported include tachycardia, mild hypertension and mild CNS depression, not requiring intervention [2].
A number of case series have found mirtazapine relatively safe in overdose, with doses less than 1000mg unlikely to cause major toxicity.1,2Mirtazapine is deemed particularly safe due to its very weak muscarinic anticholinergic properties [3].This case illustrates a patient who developed anticholinergic delirium responsive to IV physostigmine.It is proposed that this is a likely dose effect.

Background
Serotonin toxicity is a potentially fatal drug-induced spectrum of toxicity associated with increased serotonergic activity in both the peripheral and central nervous systems.Improvement is usually seen within 24-72 hours following withdrawal of the offending agent(s).

Case
A 22-year-old female was admitted with a presumed mixed serotonin and anticholinergic toxicity on the background of significant psychiatric disease.The patient exhibited unusually prolonged symptoms of serotonin toxicity, with central and peripheral nervous system symptoms continuing for 11 days.

Discussion
Possible reasons for these unusually prolonged symptoms likely include gastric stasis (partially attributable to anticholinergic toxicity), formation of a pharmacobezoar exacerbated by the presence of cellulose derivatives in the ingested drugs, the co-administration of fentanyl in the intensive care unit, and the development of an acute kidney injury secondary to severe rhabdomyolysis (creatinine kinase of 119,473 U/L).
Possible reasons for the severity of the rhabdomyolysis the patient developed include that obesity, lamotrigine toxicity, and severe muscle rigidity associated with serotonin toxicity as likely contributors.

Background
Insulin overdose can cause significant injury or death from hypoglycaemia.Until 2020, the New Zealand National Poison Centre (NZNPC) typically recommended any insulin injection outside therapeutic use requires medical assessment.Data from the US suggest that many insulin exposures can safely be managed at home.This study aims to provide information on the types and number of calls to NZNPC involving insulin exposure.

Methods
A retrospective analysis of calls reported to NZNPC about human exposures to insulin injection, between 1 January 2010 and 31 December 2019 was performed.Information was collected on calls per year, time of day, age, treatment classification, type of insulin, the reason for exposure, and symptoms (excluding hyperglycaemia).Calls were excluded if multiple substances were involved or were follow-up calls on the same exposure.

Results
NZNPC had 282 single-substance calls involving insulin injections over the study period.The number of calls per year has increased from 19 in 2010 to 77 in 2019.Calls occurred commonly at 8 am or 10 pm.Patients between 35 and 64 years made up 27.3% of cases, 27% were ≥65 years, and 32.3% were "age unknown adult." Medical assessment was advised in 92% of cases.Rapid-acting insulin was involved in 47.5% of cases.Common reasons for the exposure included mistaking types of insulin, e.g.taking rapid-acting again instead of long-acting (34.4%,where stated) and double dosing (18.4%).Symptoms were reported in 14.9% of calls, commonly dizziness/ drowsiness (3.2%), shakiness (2.8%), and anxiety (1.8%).Hypoglycaemia was only reported in 1.4% of cases.

Discussion
Insulin injection calls increased over the study period, with a large proportion referred in for medical assessment.Most exposures related to therapeutic drug errors, often with rapid-acting insulin.Very few effects, including hypoglycaemia, were reported at the time of the call.This study provided information for NZNPC to update its triage protocols for insulin exposures, where low risk patients can be managed at home under the care of a reliable observer with instructions on monitoring, food availability, and follow-up calls from NZNPC.

Introduction
We present a case of deliberate self-poisoning with verapamil, propranolol, metformin, amisulpride and clozapine resulting in severe metabolic acidosis, cardiogenic and vasoplegic shock, who was responsive to extracorporeal treatments.

Discussion
This case demonstrates severe refractory shock responsive to extracorporeal treatments.IHD was well tolerated despite shock and associated with a temporal improvement in lactic academia.Forensic testing confirmed history and also identified other co-ingestants contributing to toxicity.

Background
Methadone is commonly implicated in unexpected deaths.Forensic laboratories report methadone blood concentrations but clinical studies report methadone plasma concentrations, and the relationship between results in these different matrices is poorly defined.An in vitro study noted methadone accumulation in dog erythrocytes (erythrocyte:plasma ratio 3.4), but in clinical samples, the blood:plasma ratio was 0.7 (methadone concentrations <512 ug/L).More clinical data at higher concentrations are required to guide forensic assessments.

Methods
Recovery of methadone in whole blood and plasma was assessed by comparing the instrument response of spiked samples versus pure samples diluted to the same concentration.Matrix effects in both sample types were assessed by comparing pre-and post-extraction spikes.
Sample preparation involved diluting 50 uL of spiked plasma/blood with 50 uL of formate buffer followed by 50 uL of internal standard solution and 350 uL of 0.1% formic acid in acetonitrile.Samples were vortexed and centrifuged before passing the supernatant through a phospholipid removal column.Samples were diluted with formate buffer before analysis on a LC-MSMS.
Methadone concentrations were measured in plasma and whole blood from the same collection tube (42 samples) collected for routine care from patients on methadone maintenance treatment admitted to hospital.

Results
Methadone recovery from whole blood and plasma exceeded 98%.Ion suppression/enhancement was negligible across both sample types.In clinical samples with concentrations up to 1500 ug/L, the blood:plasma ratio was 0.5 to 1.05.Bland-Altman analysis revealed the average difference between plasma and whole blood was 27% (95%CI 22.24% -31.75%).The line of equality was within the confidence interval, suggesting agreement between measurements.The mean blood:plasma concentration ratio was 0.7 (SD 0.1), consistent with other clinical studies.
Simple linear regression comparing whole blood to plasma returned a slope of 0.79 and regression statistic (R2) of 0.97 supporting a contribution from the red cell fraction to the whole blood methadone measurement.

Discussion
This study demonstrated excellent recovery of methadone from whole blood and plasma using the same method.Factors contributing to variability in blood:plasma ratio in the cohort may reflect distribution or redistribution kinetics related to the clinical condition prompting admission.

Introduction
Thebaine is a neurotoxic alkaloid found in some poppy seeds.In rats the half-life of intravenous thebaine is 1.1 hours, with minimal toxicity noted at the plasma concentration 1.076 mg/L.Data on thebaine pharmacokinetics in humans are limited.In 2022, non-food-grade poppy seeds high in thebaine entered the food market.We report the clinical effects and toxicokinetics in three patients who consumed poppy seed washings as a tea and provided serial whole blood samples.

Case 1
A man in his 60s presented with malaise and myoclonus soon after drinking poppy seed tea.Bloods were notable for pH 7.28, pCO2 34 mmHg, lactate 11.5 mmol/L, and creatinine 142 µmol/L, 5 hours post-ingestion.He had a witnessed seizure 7 hours post-ingestion.He was intubated and received an adrenaline infusion for hypotension and benzodiazepines in ICU.He developed oliguric acute kidney injury (peak creatinine 705 µmol/L) and rhabdomyolysis (peak creatine kinase 18,657 U/L) treated with dialysis.He was extubated day 3, dialysis was ceased day 9 and he was discharged day 18.Admission thebaine blood concentration was 2.1 mg/L which eliminated with half-life 14.8 h (n = 2 samples).

Case 2
A man in his 30s presented with myoclonus, rigidity, vomiting and dizziness after drinking poppy seed tea over 24 hours.He had pH of 7.26, pCO2 43 mmHg, lactate 5.8 mmol/L.He developed acute kidney injury (peak creatinine 186 µmol/L) and muscle injury (peak creatine kinase 855 U/L) treated with intravenous fluids on a ward.He was discharged day 4. Admission thebaine blood concentration was 4.1 mg/L which eliminated with half-life 11.6 h (95%CI 9.2-14.5 h; n = 6 samples).

Case 3
A man in his 30s presented with myoclonus and diaphoresis, and was admitted to ICU and treated with benzodiazepines.He was discharged day 5. Admission thebaine blood concentration was 2.2 mg/L which eliminated with half-life 8.3 h (n = 2 samples).

Discussion
The thebaine concentrations in these patients exceeded those in other human reports and rats.The thebaine elimination half-life is much longer in humans than rats.It is uncertain whether kidney injury impacted on the longer elimination half-life in cases 1 and 2.

Objective
Rising prevalence of e-cigarette users in Malaysia may contribute to the increasing poisoning incidences from the liquid or aerosol of these devices and occasionally, some of these incidents may include e-cigarette infused with illegal substance such as psilocybin (magic mushroom).This study evaluates the severity level of psilocybin-infused e-cigarette poisoning incidences referred to the Malaysia National Poison Centre (NPC) in tandem with other socio-demographic factors.

Methods
All psilocybin-infused e-cigarette poisoning cases referred to the NPC from 2020 and 2022 are incorporated in this study.Demographic data include age, location of exposure, circumstances of exposure and Poisoning Severity Score (PSS).Data are analyzed using the descriptive statistical method.However, these cases are self-reported by the healthcare professionals, and not all cases of e-cigarette poisoning in Malaysia are reported to the NPC.Psilocybin-infused e-cigarette poisoning is either claimed by the patients or suspected by the clinician, and there is no laboratory testing done to confirm these cases.

Introduction
Loperamide is widely available without strict limitations on purchase, and adverse effects from misuse are increasingly reported.We report a case of possible neurotoxicity post-loperamide overdose.

Case summary
A young male with a history of polysubstance use was found unconscious following overdose with 120 mg loperamide, 2 bottles vanilla essence, unquantified diazepam, and possibly codeine.Paramedics documented aspiration, hypoxaemia and GCS 3/15 unresponsive to intravenous naloxone 500 micrograms.At hospital he had tachycardia (125 beats/ min) without focal neurological changes.Investigations noted hypercarbia (pCO2 98), hyperlactaemia (5.3 mmol/L), acute kidney injury (creatinine 134 micromol/L) and negative blood ethanol concentration.Urine drug screen showed amphetamines, opiates, benzodiazepines and cannabinoids.ECG showed heart rate 122 beats/min, QRS 110 ms, QT 333 ms.Non-contrast head CT was normal.He was intubated for 48 h.Post-extubation he was disinhibited with impaired fine motor skills, mobility and cognition (MOCA 20/30).QRS progressively decreased to <100 ms 32 hours post-admission.There was gradual neuromuscular improvement over 5 days, but persisting mobility difficulties.MRI brain showed restricted diffusion in subcortical white matter of all lobes and increased T2 signal in cerebellar hemispheres, most likely due to toxic encephalopathy.EEG indicated possible posterior reversible encephalopathy syndrome.Improvements allowed discharge after 19 days.MRI 1 month post-overdose noted gliosis with small foci of encephalomalacia in white matter of frontal, parietal and occipital lobes and both cerebellar hemispheres, consistent with sequelae of toxic encephalopathy.Function improved close to baseline 3 months later.MRI brain 9 months post-overdose showed persistent but markedly improved changes in the subcortical white matter.Plasma drug concentrations measured using liquid chromatography triple quadrapole mass spectrometry, the first at 19 h post-admission returning loperamide 7.4 mg/L and N-desmethyl loperamide 85.42 mg/L, which declined with half-lives of 33 and 25 h, respectively.

Discussion
Leukoencephalopathy is an uncommon complication of opioid overdose.We hypothesise loperamide was the causative agent as this complication is not associated with the coingestants, but more data are required.Minor and slowly reversible QRS prolongation, accompanied by the prolonged elimination half-life of loperamide and its metabolite, suggests minor cardiotoxicity at measured concentrations.

A case series of systemic thebaine toxicity in NSW from non-food grade poppy seeds
Darren Roberts a , Claire Turner

Background
Drinking poppy seed washings as a tea can give opiate effects.In late 2022, a non-food grade poppy seed high in the neurotoxic alkaloid thebaine entered the food market and people consuming this as a tea experienced thebaine toxicity.We report the outcomes of this event.

Methods
Following a notification on 7th November 2022 from Queensland clinicians of unexpected severe neurotoxicity in three people consuming poppy seed tea, databases of the NSW Poisons Information Centre (PIC) and toxicology services were reviewed and an NSW Public Health Rapid, Emergency, Disease and Syndromic Surveillance search was performed of triage text of emergency presentations to NSW hospitals to identify NSW cases.A case definition was developed, and a multi-agency and multi-jurisdictional response was initiated.

Results
Within 24 hours of the notification, 10 potential NSW cases over the preceding 2 weeks were identified.Public health measures included media releases, testing for alkaloids in biological specimens, and NSW Department of Primary Industries investigated alleged products.A clinician safety alert was issued on 9th November (advising it was a notifiable disease) and a media release on 11th November.Consumer recalls were initiated on 14th November.Overall, 15 cases of suspected or confirmed thebaine toxicity were identified in NSW between 26th October and 21st November.All were men (age 27-67 years, not recorded in two) consuming tea made from 100 to 1000 g of poppy seeds.Features included muscle spasms, myoclonus or rigidity (13), generalised seizures (3), metabolic acidosis (2), rhabdomyolysis (1), acute kidney injury (3), traumatic fractures (2), vomiting with abdominal pain (4), diaphoresis (4); 12 cases attended hospital (two required intensive care), two attended a general practitioner and one did not seek medical assistance.Treatment included benzodiazepines (9), ventilatory support and inotropes (1), dialysis (1).Testing confirmed high concentrations of thebaine and low concentrations of codeine, morphine and laudanosine in affected patients.

Discussion
A cluster of severe thebaine toxicity was reported in a group of men consuming poppy seed tea when non-food grade poppy seeds entered the food market.Multiagency collaboration identified the cause and responded promptly to minimise further harm.

Background
On 15 December 2022, NSW Health became aware of four separate families developing anticholinergic delirium after consuming baby spinach purchased from a supermarket.This triggered a public health response.

Methods
Case conference between NSW Poisons Information Centre (PIC) and One Health Branch, Health Protection NSW noted that each family consumed the same baby spinach brand and batch from the same supermarket.This prompted a national public health response, including notification of PICs and toxicology services, state health departments, food safety and standards organisations, and media.Processes for monitoring the health impact were developed and laboratory testing was arranged to support the anticholinergic syndrome diagnosed using clinical criteria.

Results
NSW Health issued a media alert on 15th December (within 24 hours of the first notification) and product recall occurred on 16th December.We developed a clinical case definition, fact sheets, and a process for identifying and investigating potential cases where PICs were a central referral point.Laboratory tests for anticholinergic alkaloids identified scopolamine and atropine in 5 admission urine samples; blood samples were negative.On 22nd December the spinach supplier acknowledged their product had been contaminated with Datura stramonium.This was consistent with the clinical and laboratory evidence.Overall, 612 potential cases were referred to PIC.Most callers were the person or a relative/friend, with only 6% of callers being healthcare professionals.The severity of poisoning reported was minor in 308 (50%), moderate in 53 (7%) and severe in one case; the rest were asymptomatic or not recorded.However, 215 (35%) of calls were categorised as symptomatic related to contaminated spinach, 84 (14%) were asymptomatic, 204 (33%) the attribution was unknown or not stated, and the remainder were not attributed to contaminated spinach.75 callers (12%) from home were referred to a doctor; two were advised to call an ambulance.

Discussion
Contaminated spinach initiated a multiagency public health and regulatory response.The call numbers represented a significant increase in PIC workload.Maintaining PICs as a central referral point appeared efficient and prevented unnecessary attendance to healthcare facilities.

Background
Accidental paediatric paracetamol liquid exposures were previously managed similar to deliberate tablet ingestions.In 2015, Australian guidelines changed to recommend a 2 hour paracetamol concentration in children <6 years with at-risk exposures to liquid preparations.If the 2 h concentration exceeds 150 mg/L then the concentration is rechecked at 4 hours post-ingestion.We evaluated our experience with this protocol.

Methods
Paracetamol exposures referred to NSW Poisons Information Centre (PIC) 2018-2022 were identified in the PIC database.Case review was restricted to calls from NSW hospitals about children <6 years with accidental liquid exposures.Clinical data were obtained from the PIC database and the hospital's electronic medical record (eMR).Management advised and received was compared to the Australian guidelines.

Results
263 patients were eligible for inclusion.14 (5.3%) of cases with incomplete data precluding eMR review were excluded.Of the remaining 249 patients, 121 (48.6%) cases were advised against blood tests, but in 9 (3.6%) cases the treating clinician performed the test and the result indicated low risk.In 128 (51.4%) cases, blood tests were advised, and in 61 (24.5%) cases this occurred at ∼2 h post-ingestion.2 patients were tested prior to 1 h post-ingestion.In 65 (28.1%)cases testing occurred after 2 h, mostly due to late arrival to hospital.In one case the doctor decided to only test at 4 h.In 14 cases (5.6%), repeat testing was performed, mostly at ∼4 h post-ingestion.Reasons included initial paracetamol concentration >150 mg/L (2), logistics with interhospital transfer (1), symptomatic patient or abnormal ALT (3), PIC advice (e.g.uncertainty in timing) (2), doctor-initiated due to first concentration >110 mg/L (1), first test too early (1), and doctor-initiated for an undocumented reason (4).In 12/14 cases the paracetamol concentration decreased between the time points.In 2/14 cases the paracetamol concentration increased: 73 to 81 mg/L, and 154 to 179 mg/L.

Discussion
The current guidance for a 2 h blood test to risk stratify at-risk exposures in this population appears to be safe and probably shortens hospital stay.A small proportion of patients received two blood tests.

Background
Increased use of e-cigarettes, changes to regulations and product innovation prompted the development of a pharmacovigilance system for poisons centres.Our objective was to develop a surveillance system to monitor products involved in e-cigarette poisoning exposures and outcomes in New South Wales (NSW).

Methods
Data relating to exposures to vape-related products were collected by Specialists in Poisons Information (SPIs) from calls to NSW Poisons Information Centre (PIC).Follow up calls were made to non-health practitioner callers to check clinical progress by a medical registrar.Hospital and ambulance medical records were also reviewed.

Results
Between 1 January 2022 and 31 December 2022, NSW PIC received 256 vape-related calls from NSW.The majority of callers were members of the public (88%) and concerning toddlers (63%).The most common implicated devices were disposable vapes (81%), Refill vape liquids were less common (15%) but they had larger volumes (range 10-1000 mL; median 200 mL) with nicotine concentrations 0-200 mg/mL (mode 100 mg/ mL).Vapes were mostly obtained from tobacconists (50%) and were not prescribed (91%).The most common routes of exposure were inhalation (73%), ingestion (21%) or dermal exposure (4%).Most exposures resulted in mild (67%) or no effects (28%) by Poisoning Severity Score, but more significant outcomes included drowsiness/lethargy (n = 13), chest pain (n = 11) and seizure (n = 4).One case of potential E-cigarette or Vaping Use-Associated Lung Injury was subsequently attributed to another cause.An adult accidentally ingested a mouthful of nicotine liquid mistaken for cough syrup required intubation.The number of vape-related calls in 2022 was a 26% increase compared to 2021.

Discussion
These findings indicate concerns about increasing vape exposures, in particular by young children which likely reflects ready accessibility to devices used by caregivers.Child safety features (e.g.child resistant closures, flow restrictors and activation requirements) were rarely reported as present.High-risk products including large volumes with high nicotine concentrations are in use and are illegally supplied without prescription.While serious poisonings were uncommon in our series, these products pose a potential for severe adverse effects.An ongoing national system for surveillance is needed to monitor and advise on poisoning prevention.

Background
Volatile substance misuse (VSM) is characterised by the intentional inhalation of vaporous chemicals contained in household or industrial products for their psychoactive effects.VSM can precipitate sudden out-of-hospital cardiac arrest (OHCA) with myocardial sensitisation to endogenous catecholamines a commonly postulated mechanism of action.We aim to describe the epidemiological characteristics and survival outcomes of patients with OHCA following VSM.

Methods
We conducted a retrospective cohort analysis of all OHCAs attended by the Queensland Ambulance Service (QAS) over a ten-year period (2012-2021).Incidents were extracted from the QAS OHCA registry which collects clinical information using the Utstein-style guidelines.Case identification was performed by text mining the clinical notes completed by paramedics, with search terms developed a priori, after reviewing known cases and published literature.

Conclusions
OHCA following VSM is a rare event that was associated with relatively favourable survival rates when prehospital resuscitation was performed.The administration of adrenaline in this cohort appears to be associated with poorer outcomes.However, this finding is limited by the small sample.

Background
Gamma hydroxybutyrate (GHB) use is associated with high risk of accidental overdose and acute severe toxicity.This study examined the pre-hospital circumstances, demographic characteristics and toxicity features of confirmed GHB-related emergency department (ED) presentations in Western Australia (WA).

Methods
This multicentre case series was conducted across three WA EDs involved in the Emerging Drugs Network of Australia, between April 2020 and July 2022.Information on patient demographics, drug exposure circumstances and ED presentation and outcome characteristics was obtained retrospectively from ambulance and hospital medical records.Laboratory-confirmed toxicology results, including GHB serum concentration, was available for all cases.

Results
A total of 45 confirmed GHB intoxications were identified.The median age was 34 years (range =21-51) and just over half of patients were female (n = 24, 53%).Most patients arrived at the ED by ambulance (82%) and triaged as requiring immediate emergency care (62% Australasian Triage Scale [ATS] 1 and 36% ATS 2).The median ED length of stay for all patients was 3.2 hours (SD =2.0 hours).Forty percent (n = 18) of patients were discharged directly home from the ED.Almost one-third were admitted to the intensive care unit (n = 14, 31%).
Loss of consciousness was common; 33 of the 41 cases (81%) with information on pre-hospital circumstances and first recorded Glasgow Coma Scale (GCS) were observed as "unresponsive" or "unconscious", and 26 (63%) also met the criteria for coma based on a first recorded GCS ≤8.Sixteen cases (39%) were observed with "agitated", "erratic" and/or "abnormal" behaviour/movements.

Conclusion
Capturing the complete toxicological picture contributing to acute drug-related harm, including laboratory confirmation of drug exposures and the context in which use and overdose occurs, carry important clinical and public health implications.

Aim
Evaluate factors associated with CT-B ordering after overdose and assess if CT-B results influenced patient management.

Methods
Retrospective analysis of overdose patients admitted to ICU and referred to the toxicology unit.Comparison of those undergoing and not undergoing CT-B prior to ICU admission, February 2020 to October 2022.
CT-B was abnormal in 13% (n = 26).No CT-B findings required acute neurosurgical intervention.Six of 37 patients (16%) with facial or head trauma had CT-B evidence of extracranial injury (sub-galeal hematoma, nasal fracture).Five patients without history of trauma had similar CT-B extracranial injuries.Three pre-hospital cardio-respiratory arrest patients had CT-B evidence of hypoxic brain-injury.Nine patients had chronic incidental brain findings.Two patients had CT-B suspicion of basilar artery thrombosis with normal CT-B-angiogram.One patient had a normal initial CT-B but developed a hemiplegia peri-extubation.Repeat CT-B revealed cerebral infarction.

Conclusion
In this series, CT-B was performed more commonly in intubated patients, those of male gender, with lower presenting GCS and suspected trauma.However, no intracranial abnormalities required acute intervention.These data suggest that developing a clinical decision rule guiding CT-B ordering may reduce unnecessary imaging and radiation exposure to patients with low risk of acute intracranial injury.

Aim
Describe the epidemiology, disposition and outcome of adult patients presenting to a toxicology unit with household bleach DSP.

Methods
Retrospective chart review of patients from August, 2015 to June, 2022, with DSP of household bleach products.Cases identified from toxicology referral database.Data included age, gender, ethnicity, product ingested, estimated ingested volume, GI symptoms, disposition (emergency department short stay unit [ED-SSU] or gastroenterology [Gastro-referred]), endoscopy results and length of hospital stay.
Ten (91%) gastro-referred patients underwent endoscopy.Zagar grading revealed two with Grade-0, two with Grade-1, two with grade-2 and two with Grade-3b findings.One Grade-3b patient developed mediastinal perforation and required surgical intervention.Revisiting history of exposure suggested the patient may have also ingested an industrial cleaning product.Seven ED-SSU patients were subsequently admitted to gastroenterology for ongoing symptoms with three undergoing endoscopy, showing minor mucosal injury.Median length of stay for ED-SSU patients was 0.33 days (IQR: 0.25-0.66)vs 2 days (IQR: 1.5-7) for Gastro-referred (p < 0.001)

Conclusion
More significant injury after bleach ingestion DSP was associated with male gender, primarily south-Asian ethnicity, larger ingested volumes, and persistent clinical symptoms resulting in early referral to gastroenterology and gastroscopy.

Protonitazene detection in a case of life-threatening opioid toxicity following use of a vape product in Australia
Rebekka Syrjanen a,b , Jennifer Schumann

Introduction
First developed in the 1950s but never registered for prescription use [1], the 2-benzylbenzimidazole class of synthetic opioids have recently re-emerged in illicit drug markets [2].There are increasing concerns over alternative administration methods for these illicit opioids, including in e-liquids for vaping devices, due to their inconspicuous use and the associated dangers of unintentional exposures [3].We describe a non-fatal intoxication involving the inhalation of the benzimidazole opioid, protonitazene, from a vape product.These data were collected as part of the Emerging Drugs Network of Australia -Victoria (EDNAV) project, an ethically approved study of emergency department presentations involving illicit substance toxicity (HREC/66506/Austin-2020) [4].

Case summary
A young male collapsed following the reported use of a tetrahydrocannabinol (THC) vape product.On initial review, the patient had pinpoint pupils but spontaneous breathing (12 breaths per minute, pulse-oximetry oxygen saturation 94%).The patient's respiratory rate subsequently declined, requiring bag-valve mask ventilation for two separate apnoeic episodes prior to hospital.Naloxone was withheld due to concerns the patient could become aggressive.The patient did not require further ventilatory support in hospital.Ground glass opacity was noted on the patient's chest x-ray, which was thought to be consistent with an aspiration event.The patient recovered uneventfully and was discharged home from the emergency department on oral antibiotics.Analysis of the patient's antemortem blood sample via liquid chromatography-tandem mass spectrometry identified protonitazene and no other drugs.

Discussion
This case presented with a hallmark opioid toxidrome, with miotic pupils, reduced consciousness, and respiratory compromise requiring ventilation, following the inhalation of a THC vape product which unknowingly contained protonitazene.Vaping of illicit substances appears to be an emerging trend and is a known route of administration for benzimidazole opioids [5].There is limited information about availability of benzimidazole opioid-containing e-liquids but protonitazene has been previously analytically detected in combination with metonitazene, pregabalin, bromazolam and nicotine within an e-liquid that was sold as THC in Wales [6].The detection of an illicit synthetic opioid within a vaping product in Australia is a concerning finding.Inadvertent exposure of high-potency opioids within vaping products could lead to significant harm.Continued monitoring is warranted to identify changes in opioid use patterns.

Introduction
Amygdalin is an aromatic cyanogenic glycoside compound and marketed under Amygdalin, Vitamin B17 or Laetrile.This case reports an intentional amygdalin "vitamin" tablet overdose resulting in fatal cyanide poisoning which surmounted into an Organ Tissue Donation (OTD) process for three recipients.

Case summary
A 56-year-old male intentionally ingested approximately 10g of Amygdalin.The calculated cyanide content was 600mg.The estimated lethal dose is 50mg.
The patient suffered an out-of-hospital cardiac arrest.Bystander and paramedic cardiopulmonary resuscitation achieved return-of-spontaneous-circulation (ROSC).Another cardiac arrest with ROSC occurred within the Emergency Department.The initial venous blood gas revealed: pH 6.85, pCO 2 71mmHg, lactate 15.0mmol/L.Stabilisation was achieved with adrenaline (100mcg/min), noradrenaline (50mcg/min), vasopressin (0.04u/min) and administration of the antidotes hydroxocobalamin and sodium thiosulfate.Despite organ support and further antidote therapy, the patient's neurological status remained unchanged.Neurological Determination of Death was confirmed within 24 hours of ICU admission.OTD suitability required a 48-hour observation period which resulted in the donation of one kidney, the liver and heart.

Discussion
Medical consensus established that the patient was near the end of life, escalation in treatment would not benefit the patient and the family was passionate about OTD.The Australian and New Zealand Intensive Care Society Statement on Death and Organ Donation notes that it is reasonable to maintain or increase supportive treatments which may preserve the possibility of OTD.In alignment with this, the continued medical care given resulted in improved haemodynamic and metabolic function.Ultimately, organ function was salvaged which preserved the possibility of OTD.
Literature review of PubMed revealed 26 reported cases of cyanide poisoning.Four involved intentional overdose.Eight cases included OTD with two being intentional overdoses.One case reported good outcomes after three months, one after nine months and five after one year.One case reported organ rejection.
The 48-hour observation period allowed monitoring of organ function.Serial lactate measurements reassured that cyanide was no longer being absorbed and circulating cyanide had been metabolised and cleared.This clarified the potential risks and benefits for the organ recipients which eventuated into the completed OTD process.

Introduction
The burden of acute illicit drug use in Australia is largely unknown.The establishment of prospective drug surveillance systems in emergency departments using analytical confirmation may facilitate the early identification of illicit and emerging drug use.In this presentation, we aimed to describe the demographics and outcomes of patients with detected illicit drugs or novel psychoactive substances in Western Australia (WA).Secondly, we described these presentations by state.

Methods
Patients presenting with severe and/or unusual clinical features consistent with recreational drug toxicity, as suspected by the treating clinician were identified from five Western Australian emergency departments participating in the Emerging Drugs Network of Australia (EDNA) between April 2020 and December 2022.Demographic and toxicology patterns in patients with and without analytically confirmed illicit drugs/ novel psychoactive substances from blood samples were collected during the emergency presentation.

Results
The cohort included 1331 severe and/or unusual toxicology presentations over the 2 year period.Illicit drugs/novel psychoactive substances were detected in 823 presentations (WA, 435; SA, 175; Victoria, 107; Queensland 106).The most frequent illicit drugs identified were methylamphetamine (n = 701, 85.1%) and gamma-hydroxybutyrate (n = 280, 34.0%).There were 206 detections of novel psychoactive substances within 124 presentations.Of all presentations with detected illicit drugs or novel psychoactive substances, 16% were admitted to the ICU.This proportion was different in each state, ranging from 3% in Queensland to 28% in Victoria.

Conclusion
The integration of clinical and analytic data in patients with severe and/or unusual toxicology presentations via EDNA, provides insight into illicit drug and novel psychoactive substance use responsible for acute harm across emergency departments in Western Australia.

Background
Paracetamol, which is an easily accessible medication, is the most common cause of severe acute liver injury in Western countries and is often a contributing factor in cases of deliberate self-poisoning (DSP).Paracetamol consumption is evident in up to 15% of adult and 50% of young person emergency department presentations for DSP.While the measurement of blood paracetamol levels has been widely recommended as a screening tool for DSP, there is little evidence to support this.No published studies have reported any cases of patients who lied about paracetamol ingestion, and required treatment.Furthermore, there are no known published Australian data.

Objective
The primary objective of this study was to determine the incidence of positive paracetamol levels (>10 mg/L) in ED presentations for DSP, in which the patients denied ingesting paracetamol.The secondary objectives were to determine the proportion of these patients who required treatment, and to determine the incidence of positive paracetamol levels in DSP patients who were unable to provide a history of ingestion.

Methods
A retrospective clinical audit was performed at a large urban emergency department, in Brisbane, Australia.All 412 paracetamol levels taken in the first 4 months of 2022 were assessed.Clinical data about the presentations were collected from electronic medical records.

Results
Descriptive statistics were used.In 251/412 (61%) presentations, the patients provided a history, and 161 (39%) were unable to provide a history.In 154 (61%) presentations with a history, DSP was indicated but paracetamol ingestion was either denied or unknown.Of these presentations, only 1 (0.6%) had a paracetamol level >10 mg/L, however it was below the treatment nomogram.Thus, none of the patients, who denied or could not recall paracetamol ingestion required treatment.Of the presentations without a history, 11 (7%) had a positive paracetamol level, 5 (4%) of whom received treatment.

Conclusion
If a patient with DSP can provide a history, the pre-test probability of a clinically significant paracetamol level is exceptionally low.These findings suggest that routine screening of DSP patients for paracetamol levels would provide negligible clinical benefit for those patients who can provide a history.

Background
In Australia, the incidence of deliberate self-poisoning with paracetamol is increasing.Ingestion of large quantities and controlled release preparations has also become more common.When patients present within 8 hours of an at-risk exposure, prompt assessment and treatment prevents significant liver injury in most cases.In 2019, a protocol was implemented at Royal Prince Alfred Hospital (RPA) which aimed to reduce treatment errors with N-acetylcysteine (NAC) and improve workflow in the ED.The key differences include early initiation of NAC using a risk assessment based on ingested paracetamol dose of ≥10 g or 200 mg/kg.Treatment with NAC used a 2 bag protocol of 200 mg/kg over 4 h followed by 200 mg/kg over 16 h in the second bag instead of 100 mg/kg.The decision to commence the first bag should be made after initial assessment, prior to laboratory results being available.The decision to continue treatment with the second bag used the paracetamol level and other pathology results as part of the risk assessment.

Methods
A retrospective audit of paracetamol poisonings over a 12-month period presenting to a single emergency department (ED) was conducted.Cases were identified through direct notification or through keyword search of triage and discharge diagnoses of all presentations to ED.
The primary outcomes of the audit include the rates of acute liver injury from paracetamol poisoning and the rate of adverse effects from the higher dose acetylcysteine.Secondary outcomes relate to compliance with the policy, including the rate of starting the first bag of NAC empirically, the proportion of these patients who required further treatment, the rate of dosing or administration errors and the rate of delay of recognition and notification of at-risk ingestions.

Results
117 presentations to our ED with paracetamol poisoning (alone or in combination) were identified from Jan to Dec 2022.Of these 74% were at-risk ingestions.Of the at-risk ingestions, only 57% were commenced on NAC empirically, and 75% of these went on to require 2 or more bags.Only 1 patient developed an ADR requiring early termination of NAC and 3 (2.5%)patients developed significant hepatotoxicity, all of whom were late presenters.
Berling a , Jared Brown b and Brendan Toy c,d a Calvary Mater Newcastle, Waratah, Australia; b NSW PIC, Westmead, Australia; c University of Newcastle, Callaghan, Australia; d Department of Intensive Care, Launceston General Hospital, Australia, Launceston, Australia

4.
Premature death after self-poisoning: a large population-based linkage study with the PAVLOVA Cohort, 2011-2020 Rose Cairns a,b , Zein Ali b , Firouzeh Noghrehchi b and Nicholas Buckley a,b a NSW Poisons Information Centre, The Children's Hospital at Westmead, Westmead, Australia; b Faculty of Medicine and Health, The University of Sydney, Sydney, Australia

5
. A longitudinal data linkage of patients with acute poisoning, evnenomation and adverse drug reactions in New South Wales, Australia, 2011-2020: the PAVLOVA Cohort Rose Cairns a,b , Zein Ali b , Jacques Raubenheimer b , Firouzeh Noghrehchi b , Kate Chitty b , Jared Brown a , Andrew Dawson a , Geoff Isbister a,c , Angela Chiew a,d , Jonathan Brett a,e and Nicholas Buckley a,b a NSW Poisons Information Centre, Westmead, Australia; b Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; c Calvary Mater Newcastle, Newcastle, Australia; d Prince of Wales Hospital, Randwick, Australia; e St Vincent's Hospital, Darlinghurst, Australia

Queensland over 8 years
JessicaArmstrong a,b , Keith Harris a,b,c , Carol Wylie c and Katherine Isoardi a,b,c a Clinical Toxicology Unit, Princess Alexandra Hospital, Brisbane, Australia; b University of Queensland, Brisbane, Australia; c Queensland Poisons Information Centre, Brisbane, Australia acute toxicology as an educational and resuscitation tool -An uptapped resource?Lindsey Campbell a , Amy Ward a , Georgina Beech a,b and Una Nic Ionmhain a,b a Liverpool Hospital, Sydney, Australia; b University of New South Wales, Sydney, Australia Introduction Cognitive aids and checklists are used as both an educational tool and an aid in the resuscitation bay for effective crew resource management to facilitate timely interventions.The use of these cognitive aid is less described in rare toxicological emergencies in the Emergency Department (ED).
Penafiel a , David Yoo a , Claire Turner b,c , Jared Brown b,c , Catherine McDonald d , Jason Tran d , Vanessa Shaw d and Darren Michael Roberts a,b

37.
Epidemiology and survival outcomes of out-of-hospital cardiac arrest following volatile substance misuse in Queensland, Australia Brendan Schultz a , Adam Rolley a,b , Tan Doan a , Daniel Bodnar a,c and Katherine Isoardi d,e a Queensland Ambulance Service, Queensland Government Department of Health, Kedron, Australia; b School of Clinical Sciences, Queensland University of Technology, Kelvin Grove, Australia; c Emergency and Trauma Centre, Royal Brisbane and Women's Hospital, Herston, Australia; d Clinical Toxicology Unit, Princess Alexandra Hospital, Woolloongabba, Australia; e Faculty of Medicine, University of Queensland, St Lucia, Australia Lim a , Andis Graudins b and Siba Sulaeman b a Monash Health Toxicology Unit, Dandenong, Australia; b Monash Health Toxicology Unit and Clinical Sciences at Monash Health, Monash University, Clayton, AustraliaBackgroundPatients admitted to ICU with drug overdose and altered consciousness often undergo CT-B to rule-out alternative diagnoses.Previous studies suggest this is a low yield investigation.
Pradilla a , Andis Graudins b and Siba Sulaeman b a Monash Health Toxicology Unit, Dandenong, Australia; b Monash Toxicology Unit Monash Health and Clinical Sciences at Monash Health, Monash University, Clayton, AustraliaBackgroundAccidental ingestion of household bleach products in children rarely results in significant morbidity.The risk of gastrointestinal injury is less well characterised in adults after deliberate self-poisoning (DSP) with bleach.
Wynter a , Elizabeth Doran a,b and Leanne Bennett a a Emergency Trauma Centre, Royal Brisbane And Women's Hospital, Brisbane, Australia; b University of Tasmania, Hobart, Australia