Challenges in the diagnosis of acute cyanide poisoning.

OBJECTIVE: The aim of this systematic review was to identify isolated acute cyanide poison cases and to identify reported signs, symptoms, and laboratory findings. METHODS: We searched MEDLINE, Cochrane Reviews, and Web of Science case reports and series using a number of MeSH descriptors pertaining to cyanide, toxicity, and poisonings. We excluded studies on plants, laboratory analyses, smoke inhalation poisonings, animals as well as non-English language articles and those in which data were not available. Data extracted included demographics, exposure characteristics, acute signs/symptoms, and medical management and outcome. RESULTS: From the initial 2976 articles retrieved, 65 articles (52 case reports, 13 case series) met inclusion criteria and described 102 patients. Most patients were unresponsive (78%), hypotensive (54%), or had respiratory failure (73%); other signs and symptoms included cardiac arrest (20%), seizures (20%), cyanosis (15%), cherry red skin (11%), and had an odor present (15%). Medical management included cyanide antidote kit (20%), sodium thiosulfate (40%), and hydroxocobalamin (29%). The majority of cases (66%) required intubation with mechanical ventilation and a substantial number (39%) developed refractory hypotension requiring vasopressor support. CONCLUSIONS: Contrary to general reviews published on cyanide toxicity, reports of cherry red skin and bitter almond odor were rare among published cyanide cases. Consistent with other studies, metabolic acidosis with significant lactic acidosis were the laboratory values consistently associated with cyanide toxicity. Healthcare providers may overlook cyanide toxicity in the differential diagnosis, if certain expected characteristics, such as the odor of almonds or a cherry red color of the skin are absent on physical examination.

Epidemiological trends in electronic cigarette exposures reported to U.S. Poison Centers.

CONTEXT: The Centers for Disease Control and Prevention (CDC) has reported an increase in electronic cigarette (e-cigarette) use in both adults and adolescents. Poison Center calls provide data on exposures pertaining to e-cigarette devices and components (including nicotine-refill cartridges), potentially identifying epidemiological trends in reported exposures over time. OBJECTIVE: To characterize the trends in e-cigarette exposures reported to United States (U.S.) Poison Centers between 01 June 2010 and 30 September 2013. METHODS: We obtained data from the American Association of Poison Control Centers (AAPCC) for all exposures involving e-cigarettes reported to the National Poison Data System (NPDS) by U.S. Poison Centers and described trends in exposures over time, demographics, geographical characteristics, clinical effects and outcomes, management site, and exposure route. RESULTS: A total of 1,700 exposures were reported to Poison Centers during this time. The most frequent age groups were children 5 years or below with 717 (42.2%) exposures and adults ages 20-39 years with 466 (27.4%) exposures. Temporal trends showed an increase of 1.36 exposures per month [95% CI: 1.16-1.56] from June 2010 through December 2012, after which exposures increased by 9.60 per month [95% CI: 8.64-10.55] from January through September 2013. The majority of patients who were followed reported that they had only minor effects. CONCLUSIONS: The majority of exposures to e-cigarette devices and components occurred in children of 5 years or below due to accidental exposure. Based on the available data, the reported exposures have resulted in minimal toxicity. Calls to Poison Centers regarding these products have rapidly increased since 2010, and continued surveillance may show changes in the epidemiological trends surrounding e-cigarette exposures.

Ingestion of false hellebore plants can cross-react with a digoxin clinical chemistry assay.

INTRODUCTION: We report a case of digoxin-like toxicity because of ingestion of foraged plants. This patient presented with nausea, vomiting, bradycardia, and hypotension after ingesting Veratrum viride (false hellebore). The patient's serum specimen demonstrated a positive digoxin level (0.38 ng/mL) measured by a clinical tubidimetric immunoassay. We hypothesize that steroidal alkaloid compounds contained in V. viride cross-react with the Multigent Digoxin immunoassay reagent antibodies. RESULTS: Plant extracts from V. viride demonstrated cross-reactivity to Multigent reagent antibodies but did not bind therapeutic DigiFab antibodies. Gas chromatography/mass spectrometry analyses identified several steroidal alkaloid compounds present in the V. viride extracts: jervine, ribigirvine, solanidine, and veratraman. CONCLUSIONS: This study indicates that compounds extracted from V. viride can cross-react with a clinical Digoxin immunoassay. Yet these extracts did not bind DigiFab antibody fragments used for therapeutic intervention. Providers should not unnecessarily administer DigiFab fragments as an antidote in symptomatic V. viride toxic patients.

Crotalid snake envenomation.

Over 5000 Americans suffer from snake bites annually, and of these, nearly one quarter are from poisonous species. Although these cases are undeniably reported, death appears to occur in only a few cases each year, and often reflects delay in obtaining medical care. Two families of venomous snake indigenous to the United States account for most envenomations: Crotalidae (pit vipers or new world vipers) and Elapidae. This article focuses on the snakes of the Crotalidae family.

Chemical warfare. Nerve agent poisoning.

The threat of civilian and military casualties from nerve agent exposure has become a greater concern over the past decade. After rapidly assessing that a nerve agent attack has occurred, emphasis must be placed on decontamination and protection of both rescuers and medical personnel from exposure. The medical system can become rapidly overwhelmed and strong emotional reactions can confuse the clinical picture. Initially, care should first be focused on supportive care, with emphasis toward aggressive airway maintenance and decontamination. Atropine should be titrated, with the goal of therapy being drying of secretions and the resolution of bronchoconstriction and bradycardia. Early administration of pralidoxime chloride maximizes antidotal efficacy. Benzodiazepines, in addition to atropine, should be administered if seizures develop. Early, aggressive medical therapy is the key to prevention of the morbidity and mortality associated with nerve agent poisoning.

Metered-dose inhalers: do emergency health care providers know what to teach?

STUDY OBJECTIVE: To evaluate the ability of emergency health care providers and patients to demonstrate the proper use of metered-dose inhalers (MDIs). DESIGN: Prospective cross-sectional survey. SETTING: Five Midwestern community teaching hospitals. PARTICIPANTS: One hundred eighty-five health care providers, comprising emergency medicine house staff (n = 60), attending emergency physicians (n = 50), and ED nurses (n = 75). Also recruited were 100 consecutive ED patients with clinical history of asthma being treated with at least one MDI for more than 3 months. INTERVENTIONS: We surveyed patients and health care providers to assess their knowledge of and ability to use a conventional MDI. The subject's technique of using a placebo inhaler was graded by a trained observer using a checklist of six essential steps. RESULTS: Forty-one percent (76 of 185) of health care providers and 49% (49 of 100) of ED asthma patients performed at least five steps correctly (P = .24). There were no significant differences in performance scores among the emergency medicine house staff (42%), attending emergency physicians (34%), and ED nurses (45%). Only 15% of all health care providers and 17% of asthma patients were able to describe how to estimate the amount of medicine left in the canister. CONCLUSION: These results suggest that many patients use MDIs improperly. Emergency physicians, house staff, and nurses responsible for instructing patients in optimal inhaler use may lack even rudimentary skills with these devices.