Rebecca Bruccoleri

A Literature Review of the Use of Sodium Bicarbonate for the Treatment of QRS Widening

Sodium bicarbonate is a well-known antidote for tricyclic antidepressant (TCA) poisoning. It has been used for over half a century to treat toxin-induced sodium channel blockade as evidenced by QRS widening on the electrocardiogram (ECG). The purpose of this review is to describe the literature regarding electrophysiological mechanisms and clinical use of this antidote after poisoning by tricyclic antidepressants and other agents. This article will also address the literature supporting an increased serum sodium concentration, alkalemia, or the combination of both as the responsible mechanism(s) for sodium bicarbonate’s antidotal properties. While sodium bicarbonate has been used as a treatment for cardiac sodium channel blockade for multiple other agents including citalopram, cocaine, flecainide, diphenhydramine, propoxyphene, and lamotrigine, it has uncertain efficacy with bupropion, propranolol, and taxine-containing plants.

An Update on Childhood Lead Poisoning

Childhood lead poisoning is a multi-faceted, complex condition, which affects not only the childs health and well-being, but also the familys housing security, economic status, job security, and stress level. This review updates the emergency department clinician on the management of childhood lead poisoning. Infants and children are at higher risk than adults for lead exposure due to their smaller size and proportionately larger dose of ingested toxins, their proximity to ground dirt and indoor dust, their energy and curiosity, their oral exploratory and pica behaviors, their proportionately larger daily water and milk intake, and dietary preferences that differ markedly from those of adults. Pediatric health care providers working in the emergency department can provide medical management, as well as preventive counseling and guidance, to parents of children presenting with evidence of acute or chronic lead poisoning.

Case Files of the Harvard Medical Toxicology Fellowship: Valacyclovir Neurotoxicity and Unintentional Overdose

A 24-year-old female with idiopathic end-stage renal disease (ESRD) for the past 8 months, currently on home peritoneal dialysis, presented to an outside hospital with progressive confusion, tremulousness, clumsiness and a sensation of being “outside her own body.” The patient had been in her usual state of health until 2 days prior, around the time she concomitantly began to have a breakout of her genital herpes. The patient was previously prescribed valacyclovir, dosed at 1000 mg twice daily × 3 days, to be taken during outbreaks. This was the first outbreak of her genital herpes since the development of her renal disease. Since starting the valacyclovir, her neurologic symptoms had gradually worsened, to the point that on the evening prior to admission, she was too confused to even complete her scheduled peritoneal dialysis. She was seen that night at an outside hospital (OSH A) where she regularly receives her care. There, she was noted to be hypertensive but otherwise had a reassuring exam. She was given labetalol orally and instructed to follow up closely with her primary care practitioner. Due to her worsening symptoms, the patient’s family called EMS the following morning, with a plan to bring the patient to OSH A. Unfortunately, en route to that hospital, the patient experienced a tonic-clonic seizure. EMS, therefore, diverted to a different hospital (OSH B), where she was found to be in status epilepticus resistant to both lorazepam and phenytoin. The patient was subsequently intubated with rapid sequence induction and further sedated with propofol, which terminated her seizure activity. Initial labs performed at OSH B showed a creatinine of 17 mg/dL (1503 μmol/L) although otherwise normal electrolytes, a negative urine and serum toxicology screen, a lumbar puncture with normal results, and a noncontrast head CTwhich was negative for acute bleed.

Response to 'Benefit effect of naloxone in benzodiazepines intoxication: Findings of a preliminary study'

We read with interest the recent study examining the use of naloxone to treat benzodiazepine intoxication. We praise the authors for exploring the potential for naloxone to treat benzodiazepine toxicity. Naloxone has been empirically used for decades in patients with a mental status depression from unknown cases. Those patients who ingested opioids will often respond while many other ingestions do not respond. Since your findings go against our understanding of receptor pharmacology (naloxone is not known to interact with the GABA receptors), we have a few questions regarding the methodology as well as how to interpret the results. Can you provide more details regarding the screening test for opioids? Since naloxone is a known antidote for opioid toxicity, it is very important to exclude their presence to validate the data obtained. For example, synthetic opioids such as methadone and fentanyl are not detected by an immunoassay, masking an effect of naloxone on reversing true opioid poisoning. Another concern we had about testing involves the benzodiazepines. While we understand the difficulty in analyzing serum for specific benzodiazepines, it is important to confirm that the patients consumed the benzodiazepine that they reported. Would screening of urine for the presence of a specific benzodiazepine be a reasonable means to confirm the history of ingestion? A patient’s history is often unreliable and may also make mistakes in the medication they take. Since the primary objective of this study was describing the patient’s clinical presentation based on the benzodiazepines they used, this would be an important consideration. Thank you for this interesting article.

A Case Report of Reversible Takotsubo Cardiomyopathy after Amphetamine/Dextroamphetamine Ingestion in a 15-Year-Old Adolescent Girl.

Stimulant medications are used in the treatment of attention deficit hyperactivity disorder and serious cardiac complications can occur when these medications are abused. We present a 15-year-old adolescent girl who was found to have a Takotsubo cardiomyopathy after acute amphetamine/dextroamphetamine ingestion.

Combination Clearance Therapy and Barbiturate Coma for Severe Carbamazepine Overdose

This case report describes the successful treatment of a severe carbamazepine overdose using a combination of therapies and presents data suggesting mitochondrial dysfunction in carbamazepine intoxication. A 15-year-old female subject presented comatose, in respiratory failure and shock, after the intentional ingestion of ∼280 extended-release 200-mg carbamazepine tablets with a peak serum concentration of 138 µg/mL (583.74 µmol/L). The patient developed clinical seizures and an EEG pattern of stimulus-induced rhythmic, periodic, or ictal discharges, suggestive of significant cortical dysfunction. Due to the extremely high drug serum concentration and clinical instability, a combination of therapies was used, including lipid emulsion therapy, plasmapheresis, hemodialysis, continuous venovenous hemodiafiltration, and endoscopic intestinal decontamination. The patient’s elevated serum lactate level with a high mixed venous saturation suggested possible mitochondrial dysfunction, prompting treatment with barbiturate coma to reduce cerebral metabolic demand. The serum carbamazepine concentration declined steadily, with resolution of lactic acidosis, no long-term end-organ damage, and return to baseline neurologic function. The patient was eventually discharged in her usual state of health. In the laboratory, we demonstrated in vitro that the active metabolite of carbamazepine hyperpolarized the mitochondrial membrane potential, supporting the hypothesis that the drug caused mitochondrial dysfunction. We thus successfully treated a life-threatening carbamazepine overdose with a combination of modalities. Future studies are required to validate this aggressive approach. The occurrence of mitochondrial dysfunction must be confirmed in patients with carbamazepine toxicity and the need to treat it validated.

Increasing the Visibility of Medical Toxicology in the Academic Hospital Setting Through Education

Not long ago, I received a consult from the ICU about a patient in profound shock with renal and liver failure. The critical care team was concerned that acetylfentanyl or another drug contaminant contributed to the patient’s condition after a recent lecture on “Designer Drugs” I delivered to the Pulmonary and Critical Care Division. Their excellent question to our toxicology service is a prime example of how exposure to the specialty of medical toxicology through a lecture can broaden the differential for a critically ill patient, increase consultations, and provide even more education to an entire medical team. In healthcare centers that sponsor a medical toxicology fellowship, the education of students, residents, and other healthcare providers is usually the responsibility of the fellow-in-training, and we should embrace this opportunity. Most emergency medicine residencies include some toxicology training and exposure with formal lectures or time on a toxicology service, but that same education is not required for other trainees in other specialties [1, 2]. Overdoses and medication errors can happen on any service at any time, so one my goals during fellowship is to improve medical toxicology education to other specialties. By increasing our presence as educators, we can also increase awareness of medical toxicology as a specialty and even improve patient care as will be seen in a series of upcoming articles in future issues of JMT [3]. There are many opportunities within an academic hospital to become involved in medical education. In an era of limited work hours and resident concern about structured teaching, toxicologists can offer high-yield lectures on a variety of topics [4]. Lectures can be given as single events or as part of a curriculum designed for a specific specialty such as internal medicine or pediatrics. Chief residents are almost always in need of speakers for resident didactics and welcome the enthusiasm of toxicology fellows and attendings who want to teach. For example, I worked closely with the chief internal medicine residents to provide interesting toxicology cases for their morning reports while acting as a fellow discussant. Furthermore, ICU rotations often have dedicated didactic time which is a wonderful opportunity to discuss exposures with a high morbidity and mortality as well as current treatment strategies. As medical toxicologists, we are uniquely skilled at linking the pre-clinical basic sciences with clinical care and can reinforce important concepts for all trainee levels. In addition, toxicology cases can be taught using simulation, and a recent study showed a higher retention rate on written tests with simulation compared to lectures [5]. Another method of increasing trainee exposure to toxicology is to offer open electives on the medical toxicology service. These electives can be advertised by curriculum coordinators, during consults, or when giving formal lectures. Other opportunities for educating healthcare personnel include giving CME lectures to off-service attendings and participating in nursing, paramedic, pharmacy, and laboratory staff education. Nurses are great advocates for calling medical toxicology once they understand our role in helping them and their patients. In teaching hospitals they prompt interns and residents on courses of action and can be a friendly reminder to these learners that medical toxicology is available. Furthermore, paramedics call poison centers in the field and appreciate pre-hospital consultation. For pharmacy and laboratory staff, we can provide a clinical context they may lack in other educational opportunities. Another benefit to becoming a medical educator in toxicology is that it is fun! Residents and students have a real interest in learning about medical toxicology. They often have a myriad of questions ranging from management to media reports. They get excited to tell you about their experiences in managing prior toxicology patients and are eager for input on how those cases were managed. Toxicologic exposures stand out to them and are highly memorable. As medical toxicologists, we are uniquely qualified to collaborate with many specialties, and our presence in the hospital should reflect this ability. We can teach important pharmacologic and toxicologic principles to students and nurses, as well as residents, fellows, and attendings from all specialties. In addition, practicing our specialty through increased consults provides great educational experiences for toxicology fellows and is important for the sustainability of medical toxicology [6]. While the benefits of a bedside consultation service are easier to measure, the impact of educating all health care providers is powerful though harder to quantify. Through medical education, we can both enhance our presence in the hospital and above all, improve the clinical care of medical toxicology patients.