Search

Chlorpromazine, one of the oldest antipsychotic medications, remains widely available and is still taken in overdose. We aimed to investigate the clinical effects of chlorpromazine overdose and determine if there is a relationship between the reported dose ingested and intensive care unit admission or endotracheal intubation. We performed a retrospective analysis of patients admitted to our toxicology tertiary referral hospital with chlorpromazine overdose (reported dose ingested greater than 300 mg) between 1987 and 2023. We extracted demographic information, details of ingestion, clinical effects and complications (Glasgow Coma Scale, hypotension [systolic blood pressure less than 90 mmHg], delirium, dysrhythmias), length of stay, intensive care unit admission, and endotracheal intubation. There were 218 chlorpromazine overdose cases, with presentations decreasing in frequency over the 36 years. The median age at presentation was 32 years (interquartile range: 25–40 years) and 143 (61 per cent) were female. The median reported dose ingested was 1,250 mg (interquartile range; 700–2,500 mg). The majority of presentations (135; 62 per cent) involved reported co-ingestion of other medications, typically benzodiazepines, paracetamol or antipsychotics. There were 76 (35 per cent) chlorpromazine alone ingestions in which there was a slightly higher median reported dose ingested of 1,650 mg (interquartile range: 763–3,000 mg) compared to the reported co-ingestion group, median reported dose ingested of 1,200 mg (interquartile range: 700–2,100 mg). Of all presentations, 36 (27 per cent) had a Glasgow Coma Scale less than 9, 50 (23 per cent) were admitted to the intensive care unit, and 32 (15 per cent) were endotracheally intubated. There was a significant difference in the median reported dose ingested between patients intubated (2,000 mg; interquartile range: 1,388–3,375 mg) and those not intubated (1,200 mg; interquartile range: 644–2,050mg; P < 0.001), and between those admitted to the intensive care unit and not admitted to the intensive care unit (P < 0.0001). The median reported dose ingested in seven chlorpromazine alone presentations who were intubated was 2,500 mg (interquartile range: 2,000–8,000 mg, range: 1,800–20,000 mg). Eighteen (8 per cent) patients developed delirium, eight (4 per cent) had hypotension, three had seizures, and there was one death. Almost one quarter of cases were admitted to the intensive care unit and over half of these were intubated. Whist the decision to admit to an intensive care unit or intubate a patient is based on clinical need, there was a significant association between reported dose ingested and requirement for endotracheal intubation. Both the frequency of presentation and reported dose ingested declined after 2013. The major limitations of the study were a retrospective design and no analytical confirmation of ingestion. We found that the most common effect of chlorpromazine overdose was central nervous system depression and that endotracheal intubation was associated with larger reported doses ingested, particularly in single chlorpromazine ingestions. [ABSTRACT FROM AUTHOR]

This document contains summaries from the Proceedings of the Toxicology and Poisons Network Australasia (TAPNA) 2023 Annual Scientific Meeting. The summaries cover various topics related to toxicology and poisoning, including the neurological effects of nitrous oxide abuse, managing poisoned patients at risk for QT interval prolongation, the misuse of amygdalin/cyanogenic glycoside products for cancer therapy, premature death after self-poisoning, a state-wide poisoning data linkage cohort in New South Wales, methaemoglobinemia caused by ingesting alkyl nitrites, and using screening questions to identify substance use disorder in patients presenting with deliberate self-poisoning. Other summaries discuss cases of aspiration pneumonitis in a clinical toxicology unit, marine animal envenomation and poisoning in Malaysia, the partitioning of methadone in blood and plasma, the management of accidental pediatric liquid paracetamol exposures, a case of non-fatal intoxication from the inhalation of synthetic opioid protonitazene through a vape product, and the use of funnel-web spider antivenom in hospitals in New South Wales and the Australian Capital Territory. The summaries provide valuable information for further research and highlight emerging risks and recommendations in the field of toxicology and poisoning. [Extracted from the article]

Objective: To evaluate the Assistant in Medicine (AiM) programme and its impact on physician burden and productivity in the ED. Methods: Calvary Mater Newcastle ED employed eight final year medical students as part‐time AiMs for a 10‐week period from October to December 2021. Each student worked one 10‐h shift per week. During these shifts, AiMs were assigned to a supervising doctor postgraduate year 3 or above to assist them with tasks including documentation, patient reviews, hospital consults, procedures, and discharge preparation. At the conclusion of each shift, the supervising doctor completed an online questionnaire of their experience. Results: Forty‐seven responses were received. Thirty‐six doctors (77%) felt they were able to see more patients in comparison to an average shift without an AiM and 40 doctors (85%) felt that having an AiM increased their overall productivity. Forty‐five doctors (96%) supported the implementation of final year medical students as AiMs as a permanent addition to the medical workforce in the ED. Conclusion: The present study demonstrates the strong potential the AiM programme has to improve productivity, workflow and efficiency in the ED. [ABSTRACT FROM AUTHOR]

Ethylene glycol (EG) is metabolized into glycolate and oxalate and may cause metabolic acidemia, neurotoxicity, acute kidney injury (AKI), and death. Historically, treatment of EG toxicity included supportive care, correction of acid–base disturbances and antidotes (ethanol or fomepizole), and extracorporeal treatments (ECTRs), such as hemodialysis. With the wider availability of fomepizole, the indications for ECTRs in EG poisoning are debated. We conducted systematic reviews of the literature following published EXTRIP methods to determine the utility of ECTRs in the management of EG toxicity. The quality of the evidence and the strength of recommendations, either strong ("we recommend") or weak/conditional ("we suggest"), were graded according to the GRADE approach. A total of 226 articles met inclusion criteria. EG was assessed as dialyzable by intermittent hemodialysis (level of evidence = B) as was glycolate (Level of evidence = C). Clinical data were available for analysis on 446 patients, in whom overall mortality was 18.7%. In the subgroup of patients with a glycolate concentration ≤ 12 mmol/L (or anion gap ≤ 28 mmol/L), mortality was 3.6%; in this subgroup, outcomes in patients receiving ECTR were not better than in those who did not receive ECTR. The EXTRIP workgroup made the following recommendations for the use of ECTR in addition to supportive care over supportive care alone in the management of EG poisoning (very low quality of evidence for all recommendations): i) Suggest ECTR if fomepizole is used and EG concentration > 50 mmol/L OR osmol gap > 50; or ii) Recommend ECTR if ethanol is used and EG concentration > 50 mmol/L OR osmol gap > 50; or iii) Recommend ECTR if glycolate concentration is > 12 mmol/L or anion gap > 27 mmol/L; or iv) Suggest ECTR if glycolate concentration 8–12 mmol/L or anion gap 23–27 mmol/L; or v) Recommend ECTR if there are severe clinical features (coma, seizures, or AKI). In most settings, the workgroup recommends using intermittent hemodialysis over other ECTRs. If intermittent hemodialysis is not available, CKRT is recommended over other types of ECTR. Cessation of ECTR is recommended once the anion gap is < 18 mmol/L or suggested if EG concentration is < 4 mmol/L. The dosage of antidotes (fomepizole or ethanol) needs to be adjusted during ECTR. [ABSTRACT FROM AUTHOR]

Context: Inpatient toxicology services undertake remote as well as inpatient management of poisoned patients. The aim of this study is to describe the introduction of a tablet-based electronic data collection tool allowing data to be captured on inpatient and remote consultations. Methods: Retrospective review of all cases entered in the database from 1 March 2014 to 28 February 2016. Data collected included demographics (age, sex), clinical details (exposure category), presentation facility and disposition. Results: The database included 3616 cases: 59 (1.6%) were excluded due to inadequate details, 122 (3.4%) had no electronic medical record available, 1985 (54.9%) presented to the inpatient unit facility and 1450 (40.1%) were external consultations. Of these 1450, 223 (6.2%) were paediatric (aged less than 12 years), 395 (10.9%) adolescent (12–17 years) and 832 (23.0%) adults (18 years and over). The proportion of paediatric cases (median age 2 y; 45.7% females) with pharmaceutical ingestions was 122 (54.7%; 95% confidence intervals (CIs): 48.2–61.1) compared with 345 (87.3%; 95% CI: 83.7–90.3) in adolescents (median age 15 y; 79.5% females). Of the adult presentations, 659 (18.2%) were metropolitan/regional facility presentations and 173 (4.8%) rural facilities with 125 (3.4%) adults subsequently transferred to the inpatient facility. Median age was 38 years (interquartile range (IQR) 35–52) with 338 (51.4%) females in the metropolitan group and 37 years (IQR 26–48) with 51 (30.5%) females in the rural group. There were more bites and stings in the rural group, 41 (23.7%; 95% CI: 18.0–30.6) versus 54 (8.2%; 95% CI: 6.3–10.5), more recreational substance exposures 27 (15.6%; 95% CI: 11.0–21.8) versus 40 (6.1%; 95% CI: 4.5–8.2) and less pharmaceutical exposures 93 (53.8%; 95% CI: 46.3–61.0) versus 462 (70.1%; 95% CI: 66.5–73.5). Conclusions: The tablet based database provided useful information on populations of poisoned patients not accessible previously. It demonstrated important differences in the types of patients presenting to rural versus metropolitan hospitals [ABSTRACT FROM AUTHOR]

Background: The assessment and management of patients with QT interval prolongation in poisoning requires an appropriate method of measuring and adjusting the QT interval for the heart rate (HR) in order to decide if the patient is at risk of life-threatening dysrhythmias, notably torsade de pointes (TdP). As the Clinical Toxicology Collaborative (CTC) workgroup reviewed the published literature on drug-induced QT interval prolongation in poisoning, it became obvious that many publications were missing essential data that were necessary to thoroughly assess and compare the evidence. The aim of this guidance document is to identify essential and ideal criteria required when reporting a case of drug-induced QT interval prolongation and/or TdP in poisoning. Methods: We employed a mixed methods approach as follows. Initially, we reviewed 188 cases of available published case reports and series in the literature regarding drug-induced QT interval prolongation and/or TdP in poisoning as the first step to another project. Common features and deficiencies were identified. Given the large gaps in reporting quality, we conducted an iterative consultative process involving all 23 members of the CTC to identify essential and ideal criteria to analyse publications of QT interval prolongation in poisoning. A priori standards were developed for acceptance or rejection of individual criteria. Results: Survey response was 100%. A minimum set of essential criteria for reporting cases of QT interval prolongation and drug-induced TdP in overdose setting are provided and a 35-item checklist is presented. Conclusions: We report a QT reporting checklist to ensure published case reports and series describing drug-induced QT interval prolongation in poisoning can contribute to the fund of knowledge of QT interval prolongation, TdP and other malignant dysrhythmias. [ABSTRACT FROM AUTHOR]

Objectives: There is an increased rate of sudden cardiac death (SCD) in mental health patients. Some antipsychotic medications are known to prolong the QT interval, thus increasing a patient's risk of SCD via the arrhythmia, torsades de pointes (TdP). Our aim was to evaluate assessment for QT prolongation within a public inpatient mental health facility by auditing electrocardiograph (ECG) use.Methods: We reviewed records of all mental health inpatient admissions to a public emergency mental health inpatient unit between 1 January 2016 and 11 February 2016. ECG availability was noted and QT interval was manually measured and assessed for risk of TdP using the QT nomogram when present. Demographic information and medication use was collected.Results: Of 263 mental health inpatient admissions, 50 (19%) presentations had an ECG. A total of four (8%) had a prolonged QT interval. Of the 50 patients with an ECG, 12 (24%) were taking medication known to prolong the QT interval.Conclusions: There was very limited risk assessment for QT prolongation in a public hospital psychiatric inpatient unit, with less than 20% of patients having an ECG performed. Our study supports an association between QT-prolonging drugs and a clinically significant prolonged QT interval; however, a larger study with routine ECG screening is required. [ABSTRACT FROM AUTHOR]

Context: The current 3-phase acetylcysteine infusion for paracetamol poisoning delivers half the dose over 15–60 min and frequently results in adverse reactions.Objective: We aimed to determine adverse reaction frequency with a modified 2-phase infusion protocol with a longer initial infusion.Materials and methods: A prospective observational study of a modified 2-phase acetylcysteine protocol was undertaken at two hospitals. Acetylcysteine was commenced on admission and ceased if paracetamol concentrations were low-risk (below the nomogram line). The first infusion was 200 mg/kg over 4–9 h based on ingestion time or 4 h for staggered/chronic ingestions. The second infusion was 100 mg/kg over 16 h. Pre-defined outcomes were frequency of adverse reactions (systemic hypersensitivity reactions or gastrointestinal); proportion with alanine transaminase (ALT) > 1000 U/L or abnormal ALT.Results: 654 paracetamol poisonings were treated with the new protocol; median age 29 y (15–98 y); 453 females; 576 acute and 78 staggered/chronic ingestions. In 420 (64%) acetylcysteine was stopped for low-risk paracetamol concentrations. An adverse reaction occurred in 229/654 admissions (35%; 95% CI: 31–39%): 173 (26.5%; 95% CI: 23–30%) only gastrointestinal, 50 (8%; 95% CI: 6–10%) skin only systemic hypersensitivity reactions; and three severe anaphylaxis (0.5%; 95% CI: 0.1–1.5%; all hypotension). Adverse reactions occurred in 111/231 (48%) receiving full treatment compared to 116/420 (28%) in whom the infusion was stopped early (absolute difference 20%; 95% CI: 13–28%; p < 0.0001). In 200 overdoses < 10 g, one had toxic paracetamol concentrations, but 53 developed reactions. Sixteen patients had an ALT > 1000 U/L and 24 an abnormal ALT attributable to paracetamol; all but one had treatment commenced >12 h post-ingestion.Conclusion: A 2-phase acetylcysteine infusion protocol results in a fewer reactions in patients with toxic paracetamol concentrations, but is not justified in patients with low-risk paracetamol concentrations. [ABSTRACT FROM PUBLISHER]

We present a case of intravenous (IV) paracetamol overdose in a nutritionally malnourished child during hospital admission. A ten-fold IV paracetamol dosing error ocurred, with delayed recognition and treatment resulting in transient hepatotoxicity, with a peak alanine transaminase (ALT) of 1378 IU/L in a 3-year-old child. Our case suggests that hepatotoxicity may occur for lower doses of IV paracetamol compared to oral ingestion, especially in the malnourished, and that a dose less than 150 mg/kg of IV paracetamol should be used to define treatment following overdose in a child with potential nutritional deficiencies. [ABSTRACT FROM AUTHOR]