Extracorporeal treatment for tricyclic antidepressant poisoning: recommendations from the EXTRIP Workgroup

The Extracorporeal Treatments In Poisoning (EXTRIP) workgroup was formed to provide recommendations on the use of extracorporeal treatments (ECTR) in poisoning. Here, the workgroup presents its results for tricyclic antidepressants (TCAs). After an extensive literature search, using a predefined methodology, the subgroup responsible for this poison reviewed the articles, extracted the data, summarized findings, and proposed structured voting statements following a predetermined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements and RAND/UCLA Appropriateness Method to quantify disagreement. Blinded votes were compiled, returned, and discussed in person at a meeting. A second vote determined the final recommendations. Seventy-seven articles met inclusion criteria. Only case reports, case series, and one poor-quality observational study were identified yielding a very low quality of evidence for all recommendations. Data on 108 patients, including 12 fatalities, were abstracted. The workgroup concluded that TCAs are not dialyzable and made the following recommendation: ECTR is not recommended in severe TCA poisoning (1D). The workgroup considers that poisoned patients with TCAs are not likely to have a clinical benefit from extracorporeal removal and recommends it NOT to be used in TCA poisoning.

Transporting children with toxicological emergencies

OBJECTIVE

Each year, the Newborn and Paediatric Emergency Transport Service (NETS) receives over 3600 calls from health professionals regarding the management and transportation of critically ill children across New South Wales, with toxicological emergencies making up 1.5% of these calls. The aim of the present study is to describe the characteristics of patients transported for toxicological emergencies and their retrieval management.

METHODS

A retrospective review of patients referred for management of a toxicological emergency between 2007 and 2011. Extracted data included patient demographics, substances involved, consultation with toxicological expertise, interventions performed and major adverse outcomes.

RESULTS

Two hundred and thirty patients, with 307 toxicological exposures, were referred to NETS, of whom 169 (73.5%) were subsequently transported. Pharmaceutical poisonings (223, 72.6%) were the most common, followed by non-pharmaceutical poisonings (61, 19.9%) and envenomation (23, 7.5%). Psychotropics, analgesics and chemicals were the most frequently ingested substances. The most common source of accidentally ingested pharmaceuticals was a family member. The most frequently given therapies were specific antidotes, in particular naloxone and N-acetylcysteine. Nearly half (43.2%) of transported children required only non-invasive monitoring. There was one death during the retrieval process.

CONCLUSIONS

Many children with toxicological emergencies require only non-invasive monitoring, which could be provided by trained ambulance crews in select scenarios. Involvement of a toxicologist in the initial consultation to identify these patients might reduce retrieval numbers and costs. Children on regular medication and those living with family members on psychotropic or cardiac drugs were identified as high-risk groups that should be targeted for medication safety education.

Effect of activated charcoal on apixaban pharmacokinetics in healthy subjects

Background

Activated charcoal is commonly used to manage overdose or accidental ingestion of medicines. This study evaluated the effect of activated charcoal on apixaban exposure in human subjects.

Methods

This was an open-label, three-treatment, three-period, randomized, crossover study of single-dose apixaban (20 mg) administered alone and with activated charcoal given at 2 or 6 h post-dose to healthy subjects. Blood samples for assay of plasma apixaban concentration were collected up to 72 h post-dose. Pharmacokinetic parameters, including peak plasma concentration (C_max), time to C_max (T_max), area under the concentration–time curve from time 0 to infinity (AUC_INF), and terminal half-life (T_½), were derived from apixaban plasma concentration–time data. A general linear mixed-effect model analysis of C_max and AUC_INF was performed to estimate the effect of activated charcoal on apixaban exposure.

Results

A total of 18 subjects were treated and completed the study. AUC_INF for apixaban without activated charcoal decreased by 50 and 28 %, respectively, when charcoal was administered at 2 and 6 h post-dose. Apixaban C_max and T_max were similar across treatments. The mean T_½ for apixaban alone (13.4 h) decreased to ~5 h when activated charcoal was administered at 2 or 6 h post-dose. Overall, apixaban was well tolerated in this healthy population, and most adverse events were consistent with the known profile of activated charcoal.

Conclusion

Administration of activated charcoal up to 6 h after apixaban reduced apixaban exposure and facilitated the elimination of apixaban. These results suggest that activated charcoal may be useful in the management of apixaban overdose or accidental ingestion.

Availability of treatment resources for the management of acute toxic exposures and poisonings in emergency departments among various types of hospitals in Palestine: a cross-sectional study

BACKGROUND

Poisoning exposures continue to be a significant cause of morbidity and mortality worldwide. The lack of facilities, treatment resources, and antidotes in hospitals may affect the treatments provided and outcomes. This study aimed to determine the availability of gastrointestinal (GI) decontamination, stabilisation, elimination enhancement resources, and antidotes for the management of acute toxic exposures and poisonings in emergency departments (EDs) among various types of governmental and private hospitals in Palestine.

METHODS

A cross-sectional study using semi-structured questionnaire was performed. Data were collected based on hospital resources; GI decontamination, stabilisation, elimination enhancement resources and antidotes from Palestinian hospitals.

RESULTS

Eighteen hospitals (94.7%) have responded. Among them, paracetamol poisoning was the most frequently reported cases by EDs (mean frequency score = 7.6 ± 2.1), followed by bee stings (mean = 6.9 ± 2.7) and organophosphate poisoning (mean = 6.7 ± 2.7). The availabilities of most resources related to GI decontamination items varied substantially with hospital type, but these differences were not statistical significant. The availability of stabilisation resources was not significantly different between hospitals types. For the availability of techniques used to enhance the elimination of toxic substances, there were variations between the hospitals types. However, these differences were not statistical significant, except for haemodialysis (p = 0.003) which was more available in governmental hospitals. For the availability of antidotes, none of the hospitals had sufficient stock of all antidotes listed. In relation to hospital type, there was variability in the availability of antidotes, but this did not reach statistical significance, except for deferoxamine (p < 0.001), which was available in all governmental hospitals but none of the private hospitals.

CONCLUSIONS

The availability of treatment resources and antidotes in Palestinian hospitals was not adequate except for stabilisation resources. The availability of such resources acts as a marker for the level of readiness of hospital EDs in Palestine for the management of acute toxic exposure and poisoning. The implementation of a minimum list of antidotes and treatment resources would be useful to increase the level of resources. Coordination between Palestinian poison control and drug information centre and hospitals is also important.

Poisoning in korean children and adolescents

Drug intoxication in children and adolescents is not uncommon in Korea. But the tendency of intoxication is changing with some factors, such as national surveillance system, Naderism and increasing concern among physicians. But the death rate of intoxication among adolescents is increasing in spite of decreasing total death rate of intoxication among children and adolescents. Therefore the physician must be concerned about the basic management of intoxication and figure out the common toxic substance among children and adolescents.

Common causes of poisoning: etiology, diagnosis and treatment

BACKGROUND

In 2011, German hospitals treated approximately 205 000 patients suffering from acute poisoning. Change is seen over time both in the types of poisoning that occur and in the indications for specific treatment.

METHODS

This article is based on a selective review of the literature, with special attention to the health reports of the German federal government, the annual reports of the GIZ-Nord Poisons Center (the poison information center for the four northwestern states of Germany, i.e. Bremen, Hamburg, Lower Saxony and Schleswig-Holstein), and the recommendations of international medical associations.

RESULTS

From 1996 to 2011, the GIZ-Nord Poisons Center answered more than 450 000 inquiries, most of which involved exposures to medical drugs, chemicals, plants, foods, or cosmetics. Poisoning was clinically manifest in only a fraction of these cases. Ethanol intoxication is the commonest type of acute poisoning and suicide by medical drug overdose is the commonest type of suicide by poisoning. Death from acute poisoning is most commonly the result of either smoke inhalation or illegal drug use. Severe poisoning is only rarely due to the ingestion of chemicals (particularly detergents and cleaning products), cosmetics, or plant matter. Medical procedures that are intended to reduce the absorption of a poison or enhance its elimination are now only rarely indicated. Antidotes (e.g., atropine, 4-dimethylaminophenol, naloxone, toluidine blue) are available for only a few kinds of poisoning. Randomized clinical trials of treatment have been carried out for only a few substances.

CONCLUSION

Most exposures to poisons can be treated with general emergency care and, if necessary, with symptomatic intensive-care measures. Poison information centers help ensure that cases of poisoning are dealt with efficiently. The data they collect are a useful aid to toxicological assessment and can serve as a point of departure for research projects.

Updates in the general approach to the pediatric poisoned patient

Poison prevention remains essential to prevent the most vulnerable population from becoming exposed to potentially lethal toxins. The evaluation of a child presumed to have been exposed to a toxic substance should include a precise history of the exposure, a physical examination, and knowledge of current ingestions and recreational practices. New treatments and research guiding therapy continue to evolve. Poison centers and medical toxicologists can be consulted to assist with the diagnosis of medicinal/drug overdoses, for advice about the pitfalls inherent in stabilizing children who have been exposed to toxic compounds, and for treatment recommendations based on the latest research.

Overdose of drugs for attention-deficit hyperactivity disorder: clinical presentation, mechanisms of toxicity, and management

The prevalence of attention-deficit hyperactivity disorder (ADHD) in the USA is estimated at approximately 4-9% in children and 4% in adults. It is estimated that prescriptions for ADHD medications are written for more than 2.7 million children per year. In 2010, US poison centers reported 17,000 human exposures to ADHD medications, with 80% occurring in children <19 years old and 20% in adults. The drugs used for the treatment of ADHD are diverse but can be roughly separated into two groups: the stimulants such as amphetamine, methylphenidate, and modafinil; and the non-stimulants such as atomoxetine, guanfacine, and clonidine. This review focuses on mechanisms of toxicity after overdose with ADHD medications, clinical effects from overdose, and management. Amphetamine, dextroamphetamine, and methylphenidate act as substrates for the cellular monoamine transporter, especially the dopamine transporter (DAT) and less so the norepinephrine (NET) and serotonin transporter. The mechanism of toxicity is primarily related to excessive extracellular dopamine, norepinephrine, and serotonin. The primary clinical syndrome involves prominent neurological and cardiovascular effects, but secondary complications can involve renal, muscle, pulmonary, and gastrointestinal (GI) effects. In overdose, the patient may present with mydriasis, tremor, agitation, hyperreflexia, combative behavior, confusion, hallucinations, delirium, anxiety, paranoia, movement disorders, and seizures. The management of amphetamine, dextroamphetamine, and methylphenidate overdose is largely supportive, with a focus on interruption of the sympathomimetic syndrome with judicious use of benzodiazepines. In cases where agitation, delirium, and movement disorders are unresponsive to benzodiazepines, second-line therapies include antipsychotics such as ziprasidone or haloperidol, central alpha-adrenoreceptor agonists such as dexmedetomidine, or propofol. Modafinil is not US FDA approved for treatment of ADHD; however, it has been shown to improve ADHD signs and symptoms and has been used as an off-label pharmaceutical for this diagnosis in both adults and children. The mechanism of action of modafinil is complex and not fully understood. It is known to cause an increase in extracellular concentrations of dopamine, norepinephrine, and serotonin in the neocortex. Overdose with modafinil is generally of moderate severity, with reported ingestions of doses up to 8 g. The most common neurological effects include increased anxiety, agitation, headache, dizziness, insomnia, tremors, and dystonia. The management of modafinil overdose is largely supportive, with a focus on sedation, and control of dyskinesias and blood pressure. Atomoxetine is a selective presynaptic norepinephrine transporter inhibitor. The clinical presentation after overdose with atomoxetine has generally been mild. The primary effects have been drowsiness, agitation, hyperactivity, GI upset, tremor, hyperreflexia, tachycardia hypertension, and seizure. The management of atomoxetine overdose is largely supportive, with a focus on sedation, and control of dyskinesias and seizures. Clonidine is a synthetic imidazole derivative with both central and peripheral alpha-adrenergic agonist actions. The primary clinical syndrome involves prominent neurological and cardiovascular effects, with the most commonly reported features of depressed sensorium, bradycardia, and hypotension. While clonidine is an anti-hypertensive medication, a paradoxical hypertension may occur early with overdose. The clinical syndrome after overdose of guanfacine may be mixed depending on central or peripheral alpha-adrenoreceptor effects. Initial clinical effects may be drowsiness, lethargy, dry mouth, and diaphoresis. Cardiovascular effects may depend on time post-ingestion and may present as hypotension or hypertension. The management of guanfacine overdose is largely supportive, with a focus on support of blood pressure. Overdose with ADHD medications can produce major morbidity, with many cases requiring intensive care medicine and prolonged hospital stays. However, fatalities are rare with appropriate care.

Neurotoxic emergencies

This article is intended for clinicians treating neurotoxic emergencies. Presented are causative agents of neurotoxic emergencies, many of which are easily mistaken for acute psychiatric disorders. Understanding the wide variety of agents responsible for neurotoxic emergencies and the neurotransmitter interactions involved will help the psychiatrist identify and treat this challenging population.

Pesticide exposure in children

Pesticides are a collective term for a wide array of chemicals intended to kill unwanted insects, plants, molds, and rodents. Food, water, and treatment in the home, yard, and school are all potential sources of children's exposure. Exposures to pesticides may be overt or subacute, and effects range from acute to chronic toxicity. In 2008, pesticides were the ninth most common substance reported to poison control centers, and approximately 45% of all reports of pesticide poisoning were for children. Organophosphate and carbamate poisoning are perhaps the most widely known acute poisoning syndromes, can be diagnosed by depressed red blood cell cholinesterase levels, and have available antidotal therapy. However, numerous other pesticides that may cause acute toxicity, such as pyrethroid and neonicotinoid insecticides, herbicides, fungicides, and rodenticides, also have specific toxic effects; recognition of these effects may help identify acute exposures. Evidence is increasingly emerging about chronic health implications from both acute and chronic exposure. A growing body of epidemiological evidence demonstrates associations between parental use of pesticides, particularly insecticides, with acute lymphocytic leukemia and brain tumors. Prenatal, household, and occupational exposures (maternal and paternal) appear to be the largest risks. Prospective cohort studies link early-life exposure to organophosphates and organochlorine pesticides (primarily DDT) with adverse effects on neurodevelopment and behavior. Among the findings associated with increased pesticide levels are poorer mental development by using the Bayley index and increased scores on measures assessing pervasive developmental disorder, inattention, and attention-deficit/hyperactivity disorder. Related animal toxicology studies provide supportive biological plausibility for these findings. Additional data suggest that there may also be an association between parental pesticide use and adverse birth outcomes including physical birth defects, low birth weight, and fetal death, although the data are less robust than for cancer and neurodevelopmental effects. Children's exposures to pesticides should be limited as much as possible.

Significant toxicity in a young female after low-dose tricyclic antidepressant ingestion

BACKGROUND

Tricyclic antidepressant (TCA) ingestions are a relatively common pediatric ingestion, with significant potential for both cardiac and neurological toxicity. Previous studies on pediatric TCA ingestions have found the threshold of toxicity to be 5 mg/kg.

CASE

We report a case of an 8-year-old girl who presented to the emergency department with depressed mental status and seizure-like movements. An extensive workup was pursued to evaluate the cause of her mental status, which only revealed a positive urine toxicology screen for TCA. Quantified serum levels of amitriptyline were 121 ng/mL (therapeutic range, 50-300 ng/mL) and nortriptyline were 79 ng/mL (therapeutic range 70-170 ng/mL), 18 hours after onset of symptoms. Subsequent history obtained after her mental status returned to normal revealed that she had ingested amitriptyline at a dose of 0.8 mg/kg.

CONCLUSIONS

Tricyclic antidepressant ingestion has a high potential for toxicity in pediatric patients. This case suggests, contrary to previous literature, that toxicity may occur even with small doses.

The clinical toxicology of γ-hydroxybutyrate, γ-butyrolactone and 1,4-butanediol

INTRODUCTION

Gamma-hydroxybutyrate (GHB) and its precursors, gamma-butyrolactone (GBL) and 1,4-butanediol (1,4-BD), are drugs of abuse which act primarily as central nervous system (CNS) depressants. In recent years, the rising recreational use of these drugs has led to an increasing burden upon health care providers. Understanding their toxicity is therefore essential for the successful management of intoxicated patients. We review the epidemiology, mechanisms of toxicity, toxicokinetics, clinical features, diagnosis, and management of poisoning due to GHB and its analogs and discuss the features and management of GHB withdrawal.

METHODS

OVID MEDLINE and ISI Web of Science databases were searched using the terms "GHB," "gamma-hydroxybutyrate," "gamma-hydroxybutyric acid," "4-hydroxybutanoic acid," "sodium oxybate," "gamma-butyrolactone," "GBL," "1,4-butanediol," and "1,4-BD" alone and in combination with the keywords "pharmacokinetics," "kinetics," "poisoning," "poison," "toxicity," "ingestion," "adverse effects," "overdose," and "intoxication." In addition, bibliographies of identified articles were screened for additional relevant studies including nonindexed reports. Non-peer-reviewed sources were also included: books, relevant newspaper reports, and applicable Internet resources. These searches produced 2059 nonduplicate citations of which 219 were considered relevant.

EPIDEMIOLOGY

There is limited information regarding statistical trends on world-wide use of GHB and its analogs. European data suggests that the use of GHB is generally low; however, there is some evidence of higher use among some sub-populations, settings, and geographical areas. In the United States of America, poison control center data have shown that enquiries regarding GHB have decreased between 2002 and 2010 suggesting a decline in use over this timeframe.

MECHANISMS OF ACTION

GHB is an endogenous neurotransmitter synthesized from glutamate with a high affinity for GHB-receptors, present on both on pre- and postsynaptic neurons, thereby inhibiting GABA release. In overdose, GHB acts both directly as a partial GABA(b) receptor agonist and indirectly through its metabolism to form GABA.

TOXICOKINETICS

GHB is rapidly absorbed by the oral route with peak blood concentrations typically occurring within 1 hour. It has a relatively small volume of distribution and is rapidly distributed across the blood-brain barrier. GHB is metabolized primarily in the liver and is eliminated rapidly with a reported 20-60 minute half-life. The majority of a dose is eliminated completely within 4-8 hours. The related chemicals, 1,4-butanediol and gamma butyrolactone, are metabolized endogenously to GHB. CLINICAL FEATURES OF POISONING: GHB produces CNS and respiratory depression of relatively short duration. Other commonly reported features include gastrointestinal upset, bradycardia, myoclonus, and hypothermia. Fatalities have been reported. MANAGEMENT OF POISONING: Supportive care is the mainstay of management with primary emphasis on respiratory and cardiovascular support. Airway protection, intubation, and/or assisted ventilation may be indicated for severe respiratory depression. Gastrointestinal decontamination is unlikely to be beneficial. Pharmacological intervention is rarely required for bradycardia; however, atropine administration may occasionally be warranted. WITHDRAWAL SYNDROME: Abstinence after chronic use may result in a withdrawal syndrome, which may persist for days in severe cases. Features include auditory and visual hallucinations, tremors, tachycardia, hypertension, sweating, anxiety, agitation, paranoia, insomnia, disorientation, confusion, and aggression/combativeness. Benzodiazepine administration appears to be the treatment of choice, with barbiturates, baclofen, or propofol as second line management options.

CONCLUSIONS

GHB poisoning can cause potentially life-threatening CNS and respiratory depression, requiring appropriate, symptom-directed supportive care to ensure complete recovery. Withdrawal from GHB may continue for up to 21 days and can be life-threatening, though treatment with benzodiazepines is usually effective.

Patterns of toxicity and factors influencing severity in acute adult trimipramine poisoning

AIMS

To analyze the clinical features of trimipramine poisoning, identify a minimal toxic dose, and the dose bearing a 50% risk of developing a moderate, severe or fatal outcome.

METHODS

All acute adult trimipramine monointoxications reported by physicians to the Swiss Toxicological Information Centre between January 1992 and December 2009 were identified.

RESULTS

Two hundred and thirty cases (26 confirmed and 204 probable) were analyzed, the mean age was 35.7 years and 74% were females. One hundred and thirty-seven patients showed mild, 54 moderate and 21 severe symptoms. Three cases were fatal due to refractory cardiovascular collapse. Ninety-three per cent of the events were attempted or completed suicides. The most common symptoms were central nervous system depression (79.2%), tachycardia (19.1%) and QT(c) prolongation (13.9%). The severity of poisoning depended significantly on the ingested dose (P < 0.001). The minimal dose for moderate symptoms was 250 mg (median dose 1.2 g) and 850 mg for severe symptoms (median dose 2.7 g). The dose for a 50% risk of developing a moderate, severe or fatal outcome was 5.11 g. In 38 patients early gastrointestinal decontamination was performed. Overall, these patients ingested higher trimipramine doses than the late- or not-decontaminated patients (P = 0.113). The median doses were also higher in the decontaminated group within each severity category except in the fatal cases.

CONCLUSIONS

We demonstrated that moderate trimipramine poisoning can already occur after ingestion of doses in the high therapeutic range. Poisoned patients have to be monitored for central nervous system depression, dysrhythmias and QT(c) prolongation. Early decontamination might be beneficial.

Bioterrorism: Toxins as Weapons

The potential for biological weapons to be used in terrorism is a real possibility. Biological weapons include infectious agents and toxins. Toxins are poisons produced by living organisms. Toxins relevant to bioterrorism include ricin, botulinum, Clostridium perfrigens epsilson toxin, conotoxins, shigatoxins, saxitoxins, tetrodotoxins, mycotoxins, and nicotine. Toxins have properties of biological and chemical weapons. Unlike pathogens, toxins do not produce an infection. Ricin causes multiorgan toxicity by blocking protein synthesis. Botulinum blocks acetylcholine in the peripheral nervous system leading to muscle paralysis. Epsilon toxin damages cell membranes. Conotoxins block potassium and sodium channels in neurons. Shigatoxins inhibit protein synthesis and induce apoptosis. Saxitoxin and tetrodotoxin inhibit sodium channels in neurons. Mycotoxins include aflatoxins and trichothecenes. Aflatoxins are carcinogens. Trichothecenes inhibit protein and nucleic acid synthesis. Nicotine produces numerous nicotinic effects in the nervous system.

Treatment of calcium channel blocker-induced cardiovascular toxicity with drug scavenging liposomes

Calcium channel blocker (CCB) overdose is potentially lethal. Verapamil and diltiazem are particularly prone to acute toxicity due to their dual effect on cardiac and vascular tissues. Unfortunately, conventional decontamination measures are ineffective in accelerating blood clearance and, to date, few efforts have been made to develop antidotes. To address the issue, injectable long-circulating liposomes bearing a transmembrane pH-gradient are proposed as efficient detoxifying agents of CCB poisoning. By scavenging the drug in situ, these circulating nanocarriers can restrict its distribution in tissues and hinder its pharmacological effect. In vitro, we showed that liposomes stability in serum and their ability to sequester CCBs could be finely-tuned by modulating their internal pH, surface charge, and lipid bilayer structure. Subsequently, we verified their efficacy in reversing the cardiovascular effects of verapamil in rats implanted with telemetric pressure/biopotential transmitters. In animals orally intoxicated to verapamil, an intravenous injection of the liposomal antidote rapidly attenuated the reduction in blood pressure. Areas under diastolic, systolic, and mean pressures curves were significantly reduced by up to 60% and the time to hemodynamic recovery was shortened from 19 to only 11 h. These findings confirm the protective effect of pH-gradient liposomes against cardiovascular failure after CBB intoxication, and endorse their potential as efficient, versatile antidotes.

Nanodetoxification: emerging role of nanomaterials in drug intoxication treatment

Treatment for intoxication involves the neutralization or clearance of a toxic compound, but the current methods of treatment are limited in their ability to safely and effectively detoxify the patient. Emerging research has focused on using nanoparticles as parenteral detoxifying agents to circulate through the body and capture toxins. The variable compositions of these nanoparticles control the mechanism in which they capture and remove specific compounds. As discussed in this article, the recent methods for utilizing nanoparticles for detoxification show great potential for intoxication treatment. However, several challenges must be overcome before a universal nanoparticle detoxification method is available for clinical use.

Indications for single-dose activated charcoal administration in acute overdose

PURPOSE OF REVIEW

Gastrointestinal decontamination in overdose patients remains a controversial problem in emergency medicine. There has been a significant decrease in the use of single-dose activated charcoal (SDAC) in recent years based on little new evidence and possibly because the overall mortality in overdose patients is low.

RECENT FINDINGS

Human volunteer studies suggest SDAC is effective and this effect occurs for up to 4 h after ingestion, but the magnitude of the reduction in area under the curve (AUC) decreases over time. Two randomized controlled trials including one recent large study did not find SDAC to be beneficial. Pharmacokinetic and pharmacodynamic studies of specific drugs in overdose suggest that for most drugs SDAC decreases drug exposure, but this does not translate to clinical benefit in all cases. The administration of SDAC is a low-risk intervention.

SUMMARY

Although SDAC is unlikely to be beneficial in many overdose patients, for some subgroups with severe poisoning, the benefits will outweigh the low risk of administration. The use of SDAC should be based on the potential toxicity of the drug ingested and the potential benefit of SDAC balanced against the willingness of the patient to take SDAC and the low risk of administration.

Does prearrival communication from a poison center to an emergency department decrease time to activated charcoal for pediatric poisoning?

OBJECTIVE

A poison center plays an important role in directing appropriate care, which is critical in reducing morbidity due to poisoning. Activated charcoal (AC) is one intervention for some poisonings. This study examined whether children with a poisoning who were preannounced by a poison center received AC earlier than patients without a referral.

METHODS

A retrospective review of AC administration in children aged 0 to 18 years in a pediatric emergency department (ED) from 2000 to 2006 was performed. Abstracted covariates were poison center referral status, age, sex, acuity, disposition, transportation mode, triage time, and time of AC administration. Analysis of variance controlling for covariates tested the equality of mean time intervals between the groups with and without a poison center referral.

RESULTS

Three hundred fifty-one cases met the inclusion criteria. One hundred thirty-five (39%) were male. Eighty cases (23%) had a poison center referral. Time from triage to charcoal administration for patients with a poison center referral was a mean of 59 (SD, 34) minutes. Time for the group without a referral was a mean of 71 (SD, 43) minutes (P = 0.0036).

CONCLUSIONS

Advanced communication from a poison center was associated with earlier administration of AC in the ED for this population. Nevertheless, the duration to charcoal administration was frequently suboptimal. Triage and prehospital practices should be reexamined to improve timeliness of AC when indicated and consider exclusion of administration if beyond an appropriate time frame. Advanced notification should be the paradigm for all poison centers, and early response protocols for poison center referrals should be used by EDs.

Gastrointestinal decontamination in the acutely poisoned patient

Objective

To define the role of gastrointestinal (GI) decontamination of the poisoned patient.

Data Sources

A computer-based PubMed/MEDLINE search of the literature on GI decontamination in the poisoned patient with cross referencing of sources.

Study Selection and Data Extraction

Clinical, animal and in vitro studies were reviewed for clinical relevance to GI decontamination of the poisoned patient.

Data Synthesis

The literature suggests that previously, widely used, aggressive approaches including the use of ipecac syrup, gastric lavage, and cathartics are now rarely recommended. Whole bowel irrigation is still often recommended for slow-release drugs, metals, and patients who "pack" or "stuff" foreign bodies filled with drugs of abuse, but with little quality data to support it. Activated charcoal (AC), single or multiple doses, was also a previous mainstay of GI decontamination, but the utility of AC is now recognized to be limited and more time dependent than previously practiced. These recommendations have resulted in several treatment guidelines that are mostly based on retrospective analysis, animal studies or small case series, and rarely based on randomized clinical trials.

Conclusions

The current literature supports limited use of GI decontamination of the poisoned patient.

Availability of decontamination, elimination enhancement, and stabilization resources for the management of acute toxic exposures and poisonings in emergency departments in Malaysia

Acute poisoning is a common medical emergency in Malaysia. Life can be saved if the patient is diagnosed properly and receives the appropriate treatment such as gastrointestinal decontamination techniques and resources to increase poison elimination according to clinical guidelines at a reasonable time. The aims of this study were to determine the availability of decontamination, elimination enhancement, and stabilization resources for the management of acute toxic exposures and poisonings in accident and emergency departments in Malaysia, and to compare the availability of such facilities among various types of hospitals. A comparative, descriptive cross-sectional study was conducted using a structured questionnaire. Seventy-four (58.3%) out of the targeted 127 hospitals replied and completed the questionnaire. The availabilities of most items related to stabilization resources were far better in general hospitals compared to district hospitals with specialists and district hospitals without specialists. These items were mechanical ventilators (p = 0.011), non-invasive positive pressure ventilators (0.024), pacemakers (p = 0.019), and transcutaneous cardiac pacing (p < 0.001). The availability of decontamination resources varied substantially with hospital type. Nevertheless, these differences did not reach statistical significance in any of the cases, whereas sodium sulphate, sorbitol, and polyethylene glycol were almost never available. The availabilities of most items related to elimination enhancement resources were far better in general hospitals and district hospitals with specialists compared to district hospitals without specialists. These items were haemodialysis (p = 0.046), haemoperfusion (p = 0.002), haemofiltration (p = 0.002), acid diuresis (p = 0.04), peritoneal dialysis (p < 0.001), and exchange transfusion (p < 0.001). Most Malaysian hospitals have certain important immediate interventions such as gastrointestinal decontamination techniques and resources to increase poison elimination. The availabilities of most facilities were far better in the general hospitals. Coordination between the National Poison Centre in Malaysia and hospitals should be established regarding the emergency facilities for effective management of poisoning cases in each hospital in order to direct the poisoned patients to the hospital where the appropriate management resources is available.

The clinical toxicology of the designer "party pills" benzylpiperazine and trifluoromethylphenylpiperazine

INTRODUCTION

Benzylpiperazine (BZP) and trifluoromethylphenylpiperazine (TFMPP) are synthetic phenylpiperazine analogues. BZP was investigated as a potential antidepressant in the early 1970s but was found unsuitable for this purpose. More recently, BZP and TFMPP have been used as substitutes for amfetamine-derived designer drugs. They were legally available in a number of countries, particularly in New Zealand, and were marketed as party pills, but are now more heavily regulated. This article will review the mechanisms of toxicity, toxicokinetics, clinical features, diagnosis, and management of poisoning due to BZP and TFMPP.

METHODS

OVID MEDLINE and ISI Web of Science were searched systematically for studies on BZP and TFMPP and the bibliographies of identified articles were screened for additional relevant studies including nonindexed reports. Nonpeer-reviewed sources were also accessed. In all, 179 papers excluding duplicates were identified and 74 were considered relevant.

MECHANISMS OF ACTION

BZP and TFMPP have stimulant and amfetamine-like properties. They enhance the release of catecholamines, particularly of dopamine, from sympathetic nerve terminals, increasing intra-synaptic concentrations. The resulting elevated intra-synaptic monoamine concentrations cause increased activation of both central and peripheral α- and β-adrenergic postsynaptic receptors. BZP has primarily dopaminergic and noradrenergic action while TFMPP has a more direct serotonin agonist activity.

TOXICOKINETICS

There is limited information on the kinetics of these drugs. Following ingestion, peak plasma concentrations are reached after 60 to 90 min. Both drugs would be expected to cross the blood brain barrier and they are metabolized mainly by hydroxylation and N-dealkylation catalyzed by cytochrome P450 and catechol-o-methyl transferase enzymes. In humans, only small amounts of both BZP and TFMPP are excreted in the urine, suggesting a low bioavailability. The serum half-lives of BZP and TFMPP are relatively short with elimination being essentially complete in 44 h for BZP and 24 h for TFMPP.

CLINICAL FEATURES

These compounds can cause harmful effects when taken recreationally. Commonly reported features include palpitations, agitation, anxiety, confusion, dizziness, headache, tremor, mydriasis, insomnia, urine retention, and vomiting. Seizures are induced in some patients even at low doses. Severe multiorgan toxicity has been reported, though fatalities have not been recorded conclusively.

MANAGEMENT

Supportive care including the termination of seizures is paramount, with relief of symptoms usually being provided by benzodiazepines alone.

CONCLUSIONS

BZP and TFMP can cause sympathomimetic effects in the intoxicated patient. Appropriate, symptom-directed supportive care should ensure a good recovery.

Toxicology today: what you need to know now

Clinicians are frequently confronted with toxicological emergencies and challenged with the task of correctly identifying the possible agents involved and providing appropriate treatments. In this review article, we describe the epidemiology of overdoses, provide a practical approach to the recognition and diagnosis of classic toxidromes, and discuss the initial management strategies that should be considered in all overdoses. In addition, we evaluate some of the most common agents involved in poisonings and present their respective treatments. Recognition of toxidromes with knowledge of indications for antidotes and their limitations for treating overdoses is crucial for the acute care of poisoned patients.

Acute poisoning among children admitted to a regional university hospital in Northern Greece

OBJECTIVES

The aim of our study was to elucidate the current pattern of acute poisoning among children admitted to a regional University Hospital in the prefecture of Evros in Northern Greece. We also compared the obtained findings with those of two previous studies performed in the same region.

METHODS

Demographic and clinical data, management, and outcome of children with acute poisoning were recorded in our region, during the past 5-years (2005-2009, period C) and compared to similar studies carried out in the periods 1985-1989 (period A) and 1995-1999 (period B).

RESULTS

Comparison between the three periods showed that in period Athe lower incidence of children's acute poisoning (CAP) was observed. Also this revealed a 20%-reduction in the frequency of poisoning over the past 5-years (period C) compared to period B (p = 0.219), a significant increase in tobacco intoxication over the years (in the order A-C; p < 0.001 for comparisons of periods A and B, and periods B and C), while poisoning from insecticides-pesticides decreased (p < 0.001). The incidence of poisoning via salicylates significantly reduced from 9.7% in period A to 6.2% in period B, and further to 4.7% in period C (p = 0.016), whereas during the same periods poisoning via paracetamol increased from 2.3% to 5.1% and then to 10.4%, respectively (p < 0.001). Atrend toward a higher incidence of suicide attempt via poisoning was found during the three periods (from 3.0% in period A to 4.7% and 6.6%, in periods B and C, respectively; p = 0.049).

CONCLUSIONS

The frequency of acute poisoning among children has decreased over the past 5 years. The incidences of poisoning via paracetamol and tobacco, and attempted suicide have increased in recent years. Targeted and continuous educational preventive programs are mandatory.

Tarka® overdose in a young child

Tarka® is a combination antihypertensive medication composed of verapamil hydrochloride and trandolapril. A 3.5-year-old female was brought to our hospital due to a sleepy condition 7 hours after an accidental ingestion of six tablets of Tarka® containing 240 mg verapamil hydrochloride and 4 mg trandolapril in each tablet. Five hours after hospitalization, her condition deteriorated and arterial pressure progressively decreased despite the treatment. Finally, a temporary pacemaker was implanted, after which the vital findings began to return to normal values. The pacemaker was removed 13 hours after implantation as normal heart rhythm was observed. There are no reports of intoxication with fixed-dose combination products, especially Tarka®, in young children in the literature. Therefore, we believe that our report can provide an insight on the toxic dose of this drug in younger children. Clinicians should keep in mind that lethargy can be the first symptom of a possible clinical deterioration, even in normotensive and normorhythmic individuals.