Faculty Bibliography

Cocaine use is common in many areas of the world, particularly the United States and Western Europe. Toxicity following the use of cocaine is associated with a wide range of clinical features. In this review, we will focus on the cocaine-associated cardiac arrhythmias and, in particular, some of the controversies in their etiology and management. Cocaine can produce arrhythmias either through the production of myocardial ischemia or as a direct result of ion channel alterations. Excessive catecholamines, combined with sodium and potassium channel blockades, give rise to a wide variety of supra-ventricular and ventricular rhythms. The animal and human evidence for ion channel dysfunction is reviewed, and the effects of catecholamines are followed from the cardiac action potential to the development of arrhythmias. Finally, theoretical constructs are combined with existing evidence to develop a rational treatment strategy for patients with cocaine-induced cardiac arrhythmias. In particular, we review the evidence concerning the controversies relating to the use of lidocaine in comparison with sodium bicarbonate, in terms of QRS prolongation secondary to sodium channel blockade

BACKGROUND: Clenbuterol is a potent, long-acting beta-adrenergic agonist that has been reported as an adulterant of heroin. We describe an atypical syndrome in five users of clenbuterol-tainted heroin. METHODS: All cases were referred to a regional Poison Control Center. Urine and blood were analyzed using gas and liquid chromatography as well as mass spectrometry. CASE SERIES: Five heroin users presented with a syndrome characterized by muscular spasm, tremor, hyperreflexia, and elevated serum creatine phosphokinase concentrations. All patients lacked findings of acute clenbuterol toxicity but tested positive for clenbuterol and negative for strychnine and a battery of common potential adulterants. CONCLUSIONS: We report five cases of a novel neuromuscular syndrome in users of clenbuterol-adulterated heroin. It is unclear whether these reactions represent an atypical response to clenbuterol or another unidentified contaminant

Ingestion of immature, environmentally stressed, or cultivar-specific Solanum species (particularly the potato) has been previously associated with gastrointestinal and neurological symptoms caused by solanaceous steroidal glycoalkaloids (SGAs). We report on two geographically, temporally disparate outbreaks of poisoning by susumber berries (Solanum torvum- Solanaceae) and on detection of alkaloids not present in non-toxic berries. Five family members in New York City participated in a traditional evening meal containing Jamaican susumber berries. All those consuming berries were symptomatic the following morning with varying degrees of gastrointestinal distress, dizziness, slurred speech, cranial nerve deficits, and ataxia. The most seriously afflicted patient developed hypertension, confusion, proximal upper extremity weakness, and hypercapnic respiratory failure requiring prolonged mechanical ventilation. A separate cohort of six patients in Toronto ate unripe Jamaican susumber berries. They presented 14h post-ingestion with varying degrees of diarrhea, weakness, facial paralysis, slurred speech, ataxia, early hypertension, and proximal weakness. Two patients had ventilatory decompensation; one required intubation. Poisonous berries appeared indistinguishable from non-toxic varieties. We isolated solasonine, larger amounts of solamargine, and other steroidal glycoalkaloids in the toxic berry strains. S. torvum poisoning can produce significant neurological and gastrointestinal effects which appear to be mediated by SGAs present in the berries

Extracorporeal removal techniques such as hemodialysis, charcoal hemoperfusion, and peritoneal dialysis have been used to remove toxins from the body. To define trends in the use of these techniques for toxin removal, we analyzed the 19,351 cases requiring extracorporeal removal reported to U.S. poison centers from 1985-2005. The number of such patients who received hemodialysis, excluding those with other medical indications, (normalized per million calls) increased from 231 to 707 whereas hemoperfusion decreased from 53 to 12 in the years 1985-2005. Peritoneal dialysis decreased from 2.2 in 1985 to 1.6 in 1991. The most common toxins removed by hemodialysis were lithium and ethylene glycol. There were more dialysis treatments for poisonings with valproate and acetaminophen in 2001-2005 than for methanol and theophylline, although hemodialysis for acetaminophen removal is generally not recommended. Theophylline was the most common toxin removed by hemoperfusion from 1985-2000, but carbamazepine became the most frequent toxin for removal during 2001-2005. Our study shows that the profile of toxins and the type of extracorporeal technique used to remove the toxins have changed over the years.Kidney International advance online publication, 17 September 2008; doi:10.1038/ki.2008.462

STUDY OBJECTIVE: Illicit drugs may be adulterated with substances other than the sought-after substance of abuse. Although the true incidence and clinical effects of this practice are unknown, geographically disparate outbreaks of clinically significant adulteration continue to occur. We report on a recent outbreak of clenbuterol-adulterated heroin occurring along the East Coast of the United States. METHODS: After identification of index cases, 5 US poison centers collaborated with state and territorial health departments to alert the public of clenbuterol-tainted heroin. A case definition of clenbuterol-tainted heroin toxicity was promulgated, and emergency departments (EDs) were asked to contact poison centers when cases were identified. RESULTS: We identified 34 probable or confirmed ED presentations in 5 states during a 6-month period. Thirteen of the 34 patients met the criteria for 'confirmed' exposures. Clenbuterol was identified in the blood and or urine of 12 of these 13 patients. Clenbuterol concentrations ranged from 2.4 to 26 ng/mL in the blood and 9.4 to 12,526 ng/mL in the urine. Symptoms included nausea, chest pain, palpitations, dyspnea, and tremor. Physical findings included significant tachycardia, hypotension, and laboratory evidence of hyperglycemia, hypokalemia, and increased lactate levels. Six patients demonstrated biochemical evidence of myocardial injury. Ten patients received beta-adrenergic antagonists without adverse effect. CONCLUSION: The adulteration of heroin by clenbuterol was associated with sympathomimetic effects, metabolic acidosis, and myocardial injury. The report also highlights how collaborative efforts among poison centers using the Centers for Disease Control and Prevention's Epi-X system rapidly identified a disease outbreak

OBJECTIVES: Despite little empiric evidence, mechanical ventilation (MV) in the setting of salicylate poisoning is considered by many to be harmful. When salicylate-poisoned patients are ventilated at conventional settings, the respiratory alkalosis is abolished, more salicylate is able to pass into the central nervous system (CNS), and neurotoxicity worsens. The objective of this study was to identify a relationship between MV, acidosis, and outcome in salicylate-poisoned patients. METHODS: The authors electronically searched a poison control center (PCC) database (2001-2007) for patients with salicylate poisoning, defined as a serum concentration > 50 mg/dL, who had MV listed as a therapy. For the 7-year study period, a total of 3,144 salicylate-poisoning cases were identified. Eleven patients met the inclusion criteria of having both salicylate concentrations > 50 mg/dL and required MV; only 7 of them had post-MV data available. RESULTS: In all seven patients with post-MV blood gas data, the post-MV pH was < 7.4. In five of six patients with recorded PCO2, the post-MV PCO2 was > 50 mm Hg. Two of the seven patients in the study group died following intubation (two patients died within 3 hours [serum salicylate concentrations, 85 and 79 mg/dL, respectively]). Another patient sustained severe neurologic injury (serum salicylate concentration, 84 mg/dL). The other four patients were ultimately discharged home. In the three patients with the worst clinical outcome, deterioration was reported within hours of intubation. CONCLUSIONS: Inadequate MV of patients with salicylate poisoning is associated with respiratory acidosis, acidemia, and clinical deterioration in this series of cases. This supports warnings about the danger of improper MV in patients with salicylate poisoning. A prospective study should be performed