Use of Margarine for the Successful Removal of Polyisobutylene in an Anhinga (Anhinga anhinga) and Great Blue Heron (Ardea herodias).

Two great blue herons (Ardea herodias) and an anhinga (Anhinga anhinga) were presented to the Wildlife Center of Texas with extensive plumage soiling from polyisobutylene (PIB), a synthetic rubber polymer used in manufacturing. All animals were provided supportive care and sedated for evaluation for hematologic and plasma biochemical values; one of the great blue herons was critically ill, based on the diagnostic evaluations and died approximately 24 hours after admission. On postmortem examination, it was diagnosed with coelomic migration of Eustrongylides species resulting in verminous peritonitis that was likely the primary cause of its poor condition and death, rather than the PIB exposure. Standard decontamination efforts with commercial liquid dish soap were unsuccessful. Application of margarine was used to emulsify the PIB on the remaining 2 birds and was followed by standard wash protocols for successful removal. These animals were successfully released after decontamination. The use of margarine for decontamination of PIB is unreported and could prove useful in future decontamination events in birds and other wildlife when traditional methods to remove hydrocarbon compounds are unsuccessful.

A review on nanoparticle-based technologies for biodetoxification.

Nanotechnology has gained significant penetration to different fields of medicine including drug delivery, disease interrogation, targeting and bio-imaging. In recent years, efforts have been put forth to assess the use of this technology in biodetoxification. In this review, we will discuss the current status of nanostructured biomaterials/nanoparticle (NP)-based technologies as a candidate biodetoxifying agent. Patient hospitalization due to illicit drug consumption, suicidal attempts and accidental toxin exposure are major challenges in the medical field. Overdoses of drugs/toxic chemicals or exposure to bacterial toxins or poisons are conventionally treated by voiding the stomach, administering activated charcoal or by using specific antidotes, if the toxin is known. Because of the limitations of these methods for safe and effective detoxification, advancements in nanotechnology may offer novel ways in intoxication support by using nanostructured biomaterials, such as liposomes, micellar nanocarriers, liquid crystalline nanoassemblies and ligand-based NPs.

Substitution effects of a carbonated hydroxyapatite biomaterial against intoxication chloride nickel-exposed rats.

AIMS: This study aimed to investigate the potential effects of a synthetic apatite (carbonated hydroxyapatite) on the detoxification of a group of male "Wistar" rats exposed to nickel chloride. METHODS: Toxicity was evaluated by rats' bioassay of nickel chloride. Wistar rats received this metal daily by gavage for seven days (4 mg/ml nickel chloride/200 g body weight, BW). To detoxify this organism, a subcutaneous implantation of the apatite is made. RESULTS: The results revealed that exposure to nickel induced oxidative stress, disorders in the balances of ferric phosphocalcic, renal failures, liver toxicity and significant increase in nickel rates in the bones of intoxicated rats. The application of the carbonated hydroxyapatite presented in this study restored those disorders back to normal. The synthetic apatite protected the rats against the toxic effects of nickel by lowering the levels of lipid peroxidation markers and improving the activities of defense enzymes. It also amended ferric and phosphocalcic equilibriums, protected liver and kidney functions and reduced the nickel rate in the bones of the rats. Overall, the results provided strong support for the protective role of carbonated hydroxyapatite in the detoxification of rats exposed to nickel. Those beneficial effects were further confirmed by physico-chemical characterization (X-ray diffraction and infrared spectroscopy), which revealed its property of anionic and cationic substitution, thus supporting its promising candidacy for future biomedical application. CONCLUSION: The hydroxyapatite is an effective biomaterial to solve health problems, particularly detoxification against metals (nickel).

[Correction of hydrodynamic disorders in severe alcohol poisoning in adolescent].

OBJECTIVE: To improve the results of treatment of children with severe alcohol poisoning as a result of investigation of water sectors of the body. METHODS: The study included 54 patients aged from 13 to 15 years with a diagnosis of acute severe alcohol poisoning. All patients were divided into three groups. At the initial examination was determined the concentration of alcohol in saliva using Express-test "Alkoskan." Bioimpedance analysis was performed; water sectors of the body were investigated by analyzer of the balance of water sectors ABC-01 "Medass." The study was conducted at the time of admission, after 12, 24 and 48 hours. RESULTS: In severe alcohol poisoning at the time of admission, it was revealed a reduction of the fluid in all studied sectors. The most effective compensation of liquid was observed in groups, where was used combination therapy included intravenous fluids based 4.0 ml/kg/hour. CONCLUSION: The treatment of severe alcohol poisoning should include fluid resuscitation about 4 ml/kg/hour. This capacity of medical care give the ability to correct adequately the water-sectoral disturbances already in the first 12 hours of hospitalization, and the inclusion to the basic therapy reamberine can contribute more effective replenishment of water sectors.

Paraphenylenediamine poisoning.

Hair dye containing paraphenylenediamine (PPD) is widely used in India because of its free availability and low cost. PPD produces local as well as systemic toxic effects when applied topically and/or ingested. It is highly toxic when taken by mouth and the outcome depends mainly on the dose taken. Important clinical manifestations are angioedema leading to dysphasia and respiratory distress, rhabdomyolysis, intravascular hemolysis, acute renal failure and hepatic necrosis. Myocarditis or fatal arrhythmia may also occur in PPD poisoning. Mainstay of management is early recognition and supportive measures as there is no specific antidote. We hereby report a young female who presented to us with features of angioedema, cardiac manifestation and hepatic dysfunction after ingesting PPD, which was treated successfully. In the absence of laboratory facilities, clinical features like angioedema and chocolate brown-colored urine could be suggestive of PPD poisoning.

Reducing the risk of death induced by aluminum phosphide poisoning: The new therapies.

Numerous people suffer from accidental or deliberate exposure to different pesticides when poisoning with aluminum phosphate (AlP) is increasing in the eastern countries. Aluminum phosphate is a conventional insecticide that quickly reacts with water or the moistures in the atmosphere and produces fatal phosphine gas, which absorbs quickly by the body. Oral consumption or inhalation of AlP leads to excessive reaction of the body such as fatigue, vomiting, fever, palpitation, vasodilatory shock, increasing blood pressure, cardiac dysfunction, pulmonary congestion, shortness of breath, and death. The garlic smell from the patient's mouth or exhale is one of the methods to recognize the positioning. Due to the lack of individual antidotes, several supportive treatments are required. The present study focused on the available and new therapies that help reduce the effect of AlP poisoning and the mortality rate. The therapies are divided into the antioxidant-related agent and the other agents. The impacts of each agent on the experimental cases are reported.

[Resuscitation in acute poisonings based on 2005 and 2010 Resuscitation Guideline]. / Postepowanie resuscytacyjne w ostrych zatruciach w oparciu o Wytyczne Resuscytacji z 2005 i 2010 roku.

Acute poisonings in USA are a leading cause of cardiac arrest, especially in youngsters. Primary survey and cardiopulmonary resuscitation for poisoning is based on ABCDE procedure. One of the most common manifestation of acute poisoning is coma. An open airway should be ensured. Endotracheal intubation should be performed by an experienced person. The mouth-to mouth method of artificial respiration can be applied ultimately. In case of cyanide, hydrogen sulfide, organophosphates and corrosives poisonings a special caution is needed and pocket mask or self-inflating bag with a face mask should be rather used. A quick poison identification and a contact with regional poison information centre regarding patient management are crucial. Different procedures include prolonged cardiopulmonary resuscitation.

Are one or two dangerous? Lidocaine and topical anesthetic exposures in children.

Topical anesthetics are found in a variety of prescription and non-prescription preparations, from teething gels to hemorrhoid creams. In 2003, there were 8576 exposures to local/topical anesthetics reported to the American Association of Poison Control Centers, with 67% of cases in the age group younger than 6 years old. This report reviews the available literature involving topical anesthetic exposures in children younger than 6 years old, including the National Library of Medicine's Pub Med database (limited to English language) and data from POISINDEX. Additionally, we reviewed the American Association of Poison Control Centers' annual reports from 1983 to 2003. There were 7 deaths in this age range from topical anesthetics. Although the number of deaths is low, the fact that there have been deaths reveals the serious nature of the toxicity that can result from these readily available non-prescription analgesics. Toxicity may result from topical absorption, ingestion, or aspiration. Additionally, toxicity can result from unintentional as well as therapeutic mishaps. Although the number of cases is limited, these medications can be toxic at low doses-which, in children younger than 6 years of age, may amount to as little as a teaspoon.

Liquid laundry detergent capsules (PODS): a review of their composition and mechanisms of toxicity, and of the circumstances, routes, features, and management of exposure.

Introduction: Liquid laundry detergent capsules (also called single-use detergent sacs; laundry pods; laundry packets) have become an increasingly popular household product worldwide. Objectives: To review the composition and mechanisms of toxicity of liquid laundry detergent, capsules, and the circumstances, routes, clinical features (and impact of packaging changes) and management of exposure. Methods: The databases PubMed and EMBASE were searched using the terms: "detergent" and "capsule", "pod", "pac" or "sac" combined with "poison", "ingest", "expos" but not "animal" or "in vitro" or "bacteria". The searches yielded 289 articles, of which 186 were excluded: 38 duplicates, 133 not relevant, 10 abstracts which had been published as a paper and 5 non-English language articles. The bibliographies of relevant articles were hand-searched which yielded 14 additional citations. Searching of abstracts from scientific meetings produced five additional citations. A total of 122 publications were relevant to the objectives of the review. Capsules and composition: Capsules typically contain anionic surfactants (20-35%), non-ionic surfactants (10-20%), propylene glycol (8-20%) and ethanol (2-5%) within a water-soluble polyvinyl alcohol membrane. Mechanisms of toxicity: Non-ionic surfactants are the primary mechanism, though anionic surfactants, ethanol and propylene glycol may also contribute. Circumstances of exposure: The majority (60%) of children are exposed when the capsule is removed from its original container. Routes of exposure: Ingestion is the most common (>85%); ocular (<15%) and dermal (<8%) exposure account for the remainder. Features following ingestion: Features develop in around half of all exposures, though >90% are minor. In those with features, vomiting occurs in some 50%; coughing and drowsiness are reported in <5%. Respiratory depression (<0.5%), central nervous system depression (<0.1%) esophageal or gastric injury (<0.5%), metabolic acidosis and hyperlactatemia (<0.05%) have been reported rarely. Of 17 deaths reported, 13 were adults and nine were suffering from cognitive impairment. Features following ocular exposure: Conjunctivitis, eye irritation and/or eye pain are commonly experienced; corneal injury is less common but complete recovery typically occurs within one week. Features following dermal exposure: Clinically important dermal toxicity seldom occurs, though skin burns can develop in <5% of cases when skin contact is prolonged. Impact of packaging changes on features: The implementation of packaging changes resulted in a fall in the number of exposures and their severity in the United States and in the number in Italy. Management-ingestion: Gut decontamination is not recommended, though small amounts of fluid can be administered orally to rinse out the mouth. Symptomatic and supportive care should be offered to all patients that develop features of toxicity. Supplemental oxygen should be administered for hypoxemia, and bronchodilators for laryngospasm/bronchospasm. Intubation and assisted ventilation may be required if CNS and respiratory depression develop. A chest radiograph should be performed if respiratory features develop. In patients with swallowing difficulties, drooling or oropharyngeal burns, endoscopy should be performed; if substantial mucosal damage is present MRI should be considered. In addition, intravenous fluids will be required if prolonged vomiting or diarrhea occur and acid-base disturbances should be corrected. Management-eye exposure: Thorough irrigation of the eye with sodium chloride 0.9% is required. Instillation of a local anesthetic will reduce discomfort and help more thorough decontamination. Due to the potential for corneal injury, fluorescein should be instilled. If ocular injury is present, the patient should be referred to an ophthalmologist. Management-skin exposure: Skin should be irrigated thoroughly with soap and water, and burns should be treated as a thermal burn. Conclusions: Accidental ingestion usually produces no or only minor features. Very rarely respiratory depression, central nervous system depression, esophageal or gastric injury, hyperlactatemia and metabolic acidosis occur. Ocular exposure results in corneal injury infrequently and skin burns can develop uncommonly following prolonged dermal contact. Of 17 deaths reported, 13 were adults and nine were suffering from cognitive impairment.

The clinical toxicology of sodium hypochlorite.

INTRODUCTION: Sodium hypochlorite is used as a bleaching and disinfecting agent and is commonly found in household bleach. OBJECTIVE: The objective is to review critically the epidemiology, mechanisms of toxicity, clinical features, diagnosis, and management of hypochlorite poisoning. METHODS: PubMed was searched from January 1950 to June 2018 using the terms "Hypochlorite", "Sodium Hypochlorite", "Sodium Oxychloride", "Hypochlorous Acid", "Bleach", "Chlorine Bleach", in combination with the keywords "poisoning", "poison", "toxicity", "ingestion", "adverse effects", "overdose", and "intoxication". In addition, bibliographies of identified articles were screened for additional relevant studies including non-indexed reports. Non-peer-reviewed sources were also included. These searches produced 110 citations which were considered relevant. EPIDEMIOLOGY: There is limited information regarding statistical trends on world-wide poisoning from sodium hypochlorite. In the United States of America, poison control center data have shown that enquiries regarding hypochlorite bleaches have ranged from 43,000 to 46,000 per year over the period 2012-2016. Mechanisms of toxicity: Hypochlorite's potential to cause toxicity is related to its oxidizing capacity and the pH of the solution. Toxicity arises from its corrosive activity upon contact with mucous membranes and skin. Features following ingestion: While small accidental ingestions are very unlikely to cause clinically significant toxicity, large ingestions may cause corrosive gastrointestinal injury and systemic effects, including metabolic acidosis, hypernatremia, and hyperchloremia. Features following dental exposure: Hypochlorite is used extensively by dentists for cleaning root canals and is safe if the solution remains within the root canal. Extrusions into the periapical area can result in severe pain with localized large and diffuse swelling and hemorrhage. Features following skin exposure: Prolonged or extensive exposure may cause skin irritation and damage to the skin or dermal hypersensitivity. Such exposures can result in either immediate or delayed-type skin reactions. High concentration solutions have caused severe chemical skin burns. Features following inhalation: Although there are only limited data, inhalation of hypochlorite alone is likely to lead to no more than mild irritation of the upper airways. Features following ocular exposure: Corneal injuries from ocular exposure are generally mild with burning discomfort and superficial disturbance of the corneal epithelium with recovery within 1 or 2 days. With higher concentration solutions, severe eye irritation can occur. DIAGNOSIS: The diagnosis can typically be made on the basis of a careful history, including details of the specific product used, its hypochlorite concentration, and the amount involved. As hypochlorite bleach produces a characteristic smell of chlorine, this may provide a diagnostic clue. In severe cases, corrosive injury is suggested on presentation because of hypersalivation, difficulty swallowing, retrosternal pain or hematemesis. MANAGEMENT: Symptom-directed supportive care is the mainstay of management. Gastrointestinal decontamination is not beneficial. Local corrosive injury is the major focus of treatment in severe cases. Fiberoptic endoscopy and CT thorax/abdomen are complimentary and have been shown to be useful in corrosive injuries in assessing the severity of injury, risk of mortality and risk of subsequent stricture formation and should be performed as soon as possible after ingestion. Dental periapical extrusion injuries should be left open for some minutes to allow bleeding through the tooth and to limit hematoma development in tissue spaces. Once the bleeding has ceased, the canal can be dressed with non-setting calcium hydroxide and sealed coronally. CONCLUSIONS: Accidental ingestion of household bleach is not normally of clinical significance. However, those who ingest a large amount of a dilute formulation or a high concentration preparation can develop severe, and rarely fatal, corrosive injury so prompt supportive care is essential as there is no specific antidote. Treatment primarily consists of symptom-directed supportive care.

[Effectiveness of pre-emptive hemodialysis with high-flux membranes for the treatment of life-threatening alcohol poisoning]. / Eficacia de la hemodiálisis precoz con membranas de alto flujo en el tratamiento de las intoxicaciones graves por alcoholes.

Alcohol intoxication (methanol, ethanol and ethylene glycol) may result in metabolic acidosis with increased anion gap, increased serum osmolal gap, and neurologic abnormalities ranging from drunkenness to coma, and death. The mortality and morbidity rates remain very high despite intensive care therapy. The toxicity of methanol and ethylene glycol is clearly correlated to the degree of metabolic acidosis. The established treatment of severe methanol and ethylene glycol intoxication is ethanol administration and hemodialysis (HD). By inhibiting the main metabolic pathway of methanol and ethylene glycol (alcohol dehydrogenase), ethanol prevents the formation of major toxic metabolites (formic acid, glycolic acid and oxalic acid). Conventional HD can reduce serum methanol, ethanol and ethylene glycol and its metabolites rapidly, but high-flux membranes should be capable of removing more toxic per hour of HD. In this report, we describe 14 cases of life-threatening alcohol intoxication (11 methanol, 1 ethanol, and 2 ethylene glycol) who were treated successfully with supportive care, ethanol infusion (methanol and ethylene glycol), and early HD with a high-flux dialyser. The median pH was 7.04 +/- 0.06 (range 6.60-7.33), median bicarbonate 9.9 +/- 1.9 mmol/l (range 1.4-25), and median base deficit 18.4 +/- 2.6 mmol/l (range 2-33). The median anion gap was 29.1 +/- 2.3 mmol/l (range 16-45) and the median osmolal gap was 119 +/- 47 mOsm/l (range 16-402). On admission there was an excellent linear correlation between the serum toxic alcohol concentrations and the osmolal gaps (R2 = 0.98, p = 0.0006). In all cases early HD corrected metabolic acidosis and osmolal abnormalities. The mortality was 7 % (1 from 14). We conclude that pre-emptive HD should be performed in severe intoxications to remove both the parent compound and its metabolites. The HD prescription should include a large surface area dialyser with high-flux membrane, a blood flow rate in excess of 250 ml/min, a modified bicarbonate bath enriched with phosphorus and potassium, and a long time session. The phosphorus and potassium-enriched bicarbonate-based dialysis solution used in patients with normal phosphorus and potassium serum levels avoided HD-induced hypophosphatemia and hypopotassemia. HD as implemented in these cases is a safe and very effective approach to the management of alcohol poisoning.

[Cocaine: new traffic mode, new detection method and new algorithm]. / Cocaine: nouveau mode de trafic, nouvelle méthode de détection et nouvelle prise en charge.

Since the beginning of the 21st century, the use of cocaine has doubled in certain European countries. Street dealers sell cocaine in small cellophane-wrapped packets each containing one gram, and that are stored in their mouth or rectum. In case of arrest, they swallow the packets that each contains enough cocaine to cause a fatal overdose. The packets cannot be detected by conventional radiology, and only an unenhanced abdominal CT allows for their detection. We present here our algorithm that integrates the diagnostic, therapeutic and medico-legal aspects of these cases. We also briefly review the treatment of acute cocaine intoxication, and present pitfalls that need to be avoided in the management of these difficult cases.

A case of synthetic cannabinoid poisoning in Croatia.

The number of new psychoactive substances (NPS), synthetic cannabinoids (SCs) in particular, is growing constantly. Because of the insufficiently explored effects on consumer health, they have become a major problem in the emergency departments. They are difficult to identify, and there are no antidotes that could reverse their detrimental effects. We report a case of poisoning of a young man who used SCs. The patient was admitted to the emergency department of the Clinical Hospital Merkur, Zagreb (Croatia) after sniffing and smoking a herbal product bought on the street. He presented with severe cognitive difficulties and visible eye redness. Other symptoms included somnolence, disorientation, loss of coordination, unsteady gait, hyporeflexia, stiffness, cramps and cold limbs, blurred vision, teeth grinding, dry mouth, tinnitus, fear, suicidal thoughts, impaired focus, memory, and speech, sedation, fatigue, depression, thought blocking, and autistic behaviour. His skin was dry, and his mucosa dry and irritated. Herbal products "Rainbow Special" and "Luminated Aroma" used by the patient were qualitatively analysed with gas chromatography / mass spectrometry (GC/MS) after direct extraction with an organic solvent. Solid-phase extraction method was used to analyse serum and urine samples. Despite the negative findings of biological samples, mostly due to the limitations of GC/MS, the clinical picture infallibly pointed to the poisoning with SCs. This was confirmed by the findings of 5-fluoro AMB (methyl 2-(1-(5-fluoropentyl)-1H-indazole-3-carboxamido)-3-methylbutanoate) in the herbal products.

Sticky situations: cyanoacrylate exposures reported to a poison control system.

INTRODUCTION: Cyanoacrylate (Super Glue®) exposures are commonly reported to poison control centers, but little has been published in the medical literature regarding these exposures. We sought to characterize cyanoacrylate exposures reported to a poison control system. METHODS: We performed a retrospective review of a poison system's database for all cases of single-substance human exposure to cyanoacrylate-containing products from 2005 to 2015. Data collected included age, gender, route of exposure, clinical effects, treatments recommended and medical outcome. RESULTS: There were a total of 893 patients, 505 (56.6%) of which were female. Patient ages ranged from 6 months to 88 years with a median of 11 years. The vast majority of exposures (n = 871, 97.5%) were unintentional, but a small number of exposures (n = 22, 2.5%) were due to intentional misuse (such as trying to stop a bleeding cut) or malicious intent (such as purposefully gluing a person's eyes shut as a prank). Routes of exposure included: ingestion, n = 337 (37.7%); ocular, n = 322 (36.1%); dermatologic, n = 285 (31.9%); inhalation, n = 16 (1.8%); nasal, n = 1 (0.1%); and otic, n = 1 (0.1%); some patients had multiple routes of exposure. Treatments recommended by the poison center included irrigation (n = 411), petroleum jelly (n = 143), mineral oil (n = 131), topical antibiotic ointment (n = 82), peanut butter (n = 6), acetone (n = 4) and WD-40® (n = 2). A total of 657 patients (73.6%) were managed on-site, while 236 (26.4%) were seen in a health care facility. Among all exposures, effects were classified as none (n = 287), minor (n = 529) and moderate (n = 77). No major effects or deaths were reported. CONCLUSIONS: In this case series, the majority of cases occurred in children and most exposures did not result in significant morbidity. Notably, there was wide variation in terms of recommended treatments; further study is needed to determine the optimal treatment method and to standardize poison center recommendations for treating patients with cyanoacrylate exposures.

[Treatment of acute lithium intoxication with high-flux haemodialysis membranes]. / Tratamiento de la intoxicación aguda por litio mediante hemodiálisis con dializadores de alta eficiencia.

Lithium carbonate is commonly prescribed for the treatment of bipolar (manic-depressive) disorders. However, because of its narrow therapeutic index an excessive elevation of serum lithium concentration, either during chronic maintenance therapy or after an acute overdose, can result in serious toxicity. In addition to supportive care, the established treatment of severe lithium toxicity is haemodialysis. Conventional haemodialysis can reduce serum lithium rapidly, but post-dialysis rebound elevations with recurrent toxicity have been documented in old publications. High-flux membranes should be capable of removing more lithium per hour of haemodialysis, but published values are not available. We report here three patients with acute lithium intoxication who were treated successfully with bicarbonate and high-flux haemodialysis membranes. Our patients presented with a severe degree of intoxication, based on the amount of drug ingested, the initial serum lithium level, the severity of neurologic symptoms and systemic manifestations. Two patients developed acute renal failure probably as a result of volume depletion since it was rapidly reversible by haemodialysis and infusion therapy. In addition, consecutive haemodialysis sessions and improvement of renal function allowed a rapid decrease in serum lithium levels without haemodynamic instability or rebound elevations in lithium concentration. The effectiveness of the procedure in these cases can be attributed to the use of bicarbonate dialysate and high-efficiency dialysers. This is the first report describing the effect of high-efficiency dialysers on lithium pharmacokinetic. Using this technique the elimination rate of lithium was found to be greater than previously reported with haemodialysis.

Poisoning due to pyrethroids.

The first pyrethroid pesticide, allethrin, was identified in 1949. Allethrin and other pyrethroids with a basic cyclopropane carboxylic ester structure are type I pyrethroids. The insecticidal activity of these synthetic pyrethroids was enhanced further by the addition of a cyano group to give alpha-cyano (type II) pyrethroids, such as cypermethrin. The finding of insecticidal activity in a group of phenylacetic 3-phenoxybenzyl esters, which lacked the cyclopropane ring but contained the alpha-cyano group (and hence were type II pyrethroids) led to the development of fenvalerate and related compounds. All pyrethroids can exist as at least four stereoisomers, each with different biological activities. They are marketed as racemic mixtures or as single isomers. In commercial formulations, the activity of pyrethroids is usually enhanced by the addition of a synergist such as piperonyl butoxide, which inhibits metabolic degradation of the active ingredient. Pyrethroids are used widely as insecticides both in the home and commercially, and in medicine for the topical treatment of scabies and headlice. In tropical countries mosquito nets are commonly soaked in solutions of deltamethrin as part of antimalarial strategies. Pyrethroids are some 2250 times more toxic to insects than mammals because insects have increased sodium channel sensitivity, smaller body size and lower body temperature. In addition, mammals are protected by poor dermal absorption and rapid metabolism to non-toxic metabolites. The mechanisms by which pyrethroids alone are toxic are complex and become more complicated when they are co-formulated with either piperonyl butoxide or an organophosphorus insecticide, or both, as these compounds inhibit pyrethroid metabolism. The main effects of pyrethroids are on sodium and chloride channels. Pyrethroids modify the gating characteristics of voltage-sensitive sodium channels to delay their closure. A protracted sodium influx (referred to as a sodium 'tail current') ensues which, if it is sufficiently large and/or long, lowers the action potential threshold and causes repetitive firing; this may be the mechanism causing paraesthesiae. At high pyrethroid concentrations, the sodium tail current may be sufficiently great to prevent further action potential generation and 'conduction block' ensues. Only low pyrethroid concentrations are necessary to modify sensory neurone function. Type II pyrethroids also decrease chloride currents through voltage-dependent chloride channels and this action probably contributes the most to the features of poisoning with type II pyrethroids. At relatively high concentrations, pyrethroids can also act on GABA-gated chloride channels, which may be responsible for the seizures seen with severe type II poisoning. Despite their extensive world-wide use, there are relatively few reports of human pyrethroid poisoning. Less than ten deaths have been reported from ingestion or following occupational exposure. Occupationally, the main route of pyrethroid absorption is through the skin. Inhalation is much less important but increases when pyrethroids are used in confined spaces. The main adverse effect of dermal exposure is paraesthesiae, presumably due to hyperactivity of cutaneous sensory nerve fibres. The face is affected most commonly and the paraesthesiae are exacerbated by sensory stimulation such as heat, sunlight, scratching, sweating or the application of water. Pyrethroid ingestion gives rise within minutes to a sore throat, nausea, vomiting and abdominal pain. There may be mouth ulceration, increased secretions and/or dysphagia. Systemic effects occur 4-48 hours after exposure. Dizziness, headache and fatigue are common, and palpitations, chest tightness and blurred vision less frequent. Coma and convulsions are the principal life-threatening features. Most patients recover within 6 days, although there were seven fatalities among 573 cases in one series and one among 48 cases in another. Management is supportive. As paraesthesiae usually resolve in 12-24 hours, specific treatment is not generally required, although topical application of dl-alpha tocopherol acetate (vitamin E) may reduce their severity.

Whole bowel irrigation as a decontamination procedure after acute drug overdose.

Whole bowel irrigation, routinely used before colonoscopy, is evaluated as a potential gastrointestinal decontamination procedure for acute drug overdose. Nine adult volunteers, who served as their own controls, each ingested 5.0 g of ampicillin trihydrate on two occasions, one week apart. Whole bowel irrigation with polyethylene glycol electrolyte lavage solution was performed one hour after one ingestion. Serial serum ampicillin levels, electrolytes, osmolalities, body weights, and hematocrits were obtained. The areas under the concentration vs time curves for ampicillin were computed for both groups, and their means were compared. Mean duration of the procedure was 234 minutes and mean volume of infused polyethylene glycol electrolyte lavage solution was 7.7 L. Whole bowel irrigation produced a 67% decrease in ampicillin absorption and there were no significant changes in body weight, hematocrit, serum electrolytes, or osmolality. We conclude that whole bowel irrigation is an effective and safe gastrointestinal decontamination procedure for acute drug ingestion.

Evaluation of efficacy of resin hemoperfusion in patients with acute 2,4-dinitrophenol poisoning by dynamic monitoring of plasma toxin concentration.

OBJECTIVE: The intoxications caused by 2,4-dinitrophenol (2,4-DNP), even death, have been frequently reported in recent years. This study aims to investigate the dynamic changes of plasma toxin concentration and explore the clinical value of resin hemoperfusion (HP) in the treatment of patients with acute 2,4-DNP poisoning. METHODS: We reported 16 cases of acute 2,4-DNP poisoning through occupational exposure due to ignoring the risk of poisoning. The blood samples were collected from the 14 survivors. According to the different treatments of resin HP, the survivors were divided into routine HP (n=5) and intensive HP (n=9) groups. Ultra high performance liquid chromatography/ tandem mass spectroscopy (UPLC-MS/MS) was used to detect the 2,4-DNP concentration in plasma in this study. RESULTS: The 14 survivors recovered very well after treatment. The initial plasma 2,4-DNP concentrations (C1) of survivors ranged from 0.25 to 41.88 µg/ml (mean (12.56±13.93) µg/ml). A positive correlation existed between initial plasma 2,4-DNP concentration (C1) and temperature. The elimination of 2,4-DNP was slow and persistent, and the total clearance rates of plasma toxin from the 1st to 3rd day (R3), the 3rd to 7th day (R3-7), and the 1st to 7th day (R7), were only (53.03±14.04)%, (55.25±10.50)%, and (78.29±10.22)%, respectively. The plasma toxin was cleared up to 25 d after poisoning in most of the patients. The R3, R3-7, and R7 in the intensive HP group were all apparently higher than those in the routine HP group, with statistical significance (P<0.05). Simultaneously, the elimination half-life (t1/2) of 2,4-DNP in the intensive HP group was apparently shorter than that in the routine HP group, with statistical significance (P<0.05). CONCLUSIONS: The clinicians should be aware of this slow and persistent process in the elimination of plasma 2,4-DNP. Higher initial plasma toxin concentration resulted in a more severe fever for the patient. According to the limited data, longer and more frequent resin HP may accelerate to eliminate the poison.

Resin hemoperfusion in ethychlorvynol overdose.

An 18-yr-old male with a severe ethchlorvynol (ECV) overdose was treated with Amberlite XAD-4 resin hemoperfusion. Plasma ECV concentration declined 33% during a 3.5-hr hemoperfusion, but rebounded substantially, peaking 6 hr later. It was estimated that 16% of ECV in the body was removed. Following hemoperfusion, plasma ECV concentrations declined linearly at a rate of 13 mg/1/day. Hemoperfusion clearance was estimated by both the traditional method, using extraction ratios across the column and column blood flow (Cl = 270 ml/min), and an alternative method, using blood concentrations during hemoperfusion and recovery of drug from the resin (Cl = 184 ml/min). The latter may provide a better estimate of hemoperfusion clearance because it is not subject to error (which can be substantial) in measurement of column blood flow. The resin completely extracted ECV from plasma, resulting in a rate of elimination 10 times that expected from endogenous processes. To aid in kinetic analysis, blood:plasma partition and protein binding of ECV in 3 normal subjects were also examined. Blood:plasma ratio averaged 0.88 +/- 0.04 and fraction free in plasma, 0.38 +/- 0.02; neither changed as a function of blood concentration between 27 and 108 mg/1. Our data indicate that removal of ECV from the overdosed patient by hemoperfusion is limited by extensive distribution in and slow redistribution from body tissues, but because of the extremely slow rate of removal by the body and the severe nature of the ECV overdose, Amberlite XAD-4 hemoperfusion may be clinically useful.