Faculty Bibliography

INTRODUCTION:Assays for ethylene glycol (EG) with a rapid turn-around time are not routinely available. Clinicians must rely on historical features and readily available clinical tests, combined with clinical acumen, to guide the initial management of suspected EG poisoning. Hypocalcemia has been suggested as a clue supporting the diagnosis of EG poisoning in patients presenting with an unexplained high anion gap metabolic acidosis (HAGMA). A previous small study challenged this assumption. METHODS:This was a retrospective case series of one state's poison control system of confirmed EG-poisoned patients between September 2017 and April 2021. The definition of EG poisoning was based on suspected EG ingestion and a serum EG concentration > 5 mg/dL. Patients who were suspected to have EG toxicity but did not have a confirmed EG concentration or the EG concentration was less than 5 mg/dL were excluded. Routine laboratory studies were recorded for all patients. Comparisons between serum calcium on presentation to presenting blood pH, bicarbonate, anion gap, and creatinine were assessed for correlation. RESULTS:There was no correlation between the presenting calcium and either pH or creatinine. There was a weak positive correlation between the initial serum calcium and anion gap, a weak negative correlation between the initial serum calcium and bicarbonate. CONCLUSION:On hospital presentation, hypocalcemia was not associated with EG poisoning, even in patients with a HAGMA. A normal serum calcium on presentation does not exclude the diagnosis of EG poisoning.

DISCLAIMER/CONCLUSIONS:In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. PURPOSE/OBJECTIVE:The case of a patient with a massive acute enoxaparin overdose managed with observation and minimal doses of protamine sulfate is reported. SUMMARY/CONCLUSIONS:Acute enoxaparin overdoses are uncommonly reported and management is widely variable. A 25-year-old man presented to the emergency department (ED) shortly after reporting that he had attempted suicide by injecting himself with 31 syringes of 80 mg of enoxaparin (a total of 2,480 mg) in the abdomen and other areas of his body. The patient also had self-inflicted superficial lacerations of the forearm. Due to concern over suspected compartment syndrome in the forearm, 25 mg of protamine was administered. Approximately 11 hours after reported enoxaparin self-injection, the patient's activated partial thromboplastin time (aPTT) was 206 seconds, prompting administration of an additional 50 mg of protamine. Three hours later, the aPTT had decreased to 79 seconds, then rose over several hours to 127 seconds before gradually declining to normal values. Protamine administration had no appreciable impact on anti-factor Xa activity. The patient did not require any blood products during the hospital admission. There were no further complications, and the patient was discharged to the inpatient psychiatry service on hospital day 8. CONCLUSION/CONCLUSIONS:The case highlights the role of protamine as a reversal agent in the management of low-molecular-weight heparin overdoses. The optimal dosing and efficacy of protamine for this indication needs further investigation.

INTRODUCTION/BACKGROUND:Clozapine is an atypical antipsychotic used to treat refractory schizophrenia; in both therapeutic use and overdose, it can cause significant toxicity. We report two young siblings who developed altered mental status after ingesting clozapine due to a pharmacy dispensing error. CASE REPORT/METHODS:A 5-year-old girl and her 19-month-old sister presented to the emergency department (ED) with altered mental status after they took their first dose of what was believed to be cimetidine, prescribed to treat molluscum contagiosum. Both children were discharged after a brief period of observation in the ED. Two days later, when the older child continued to be symptomatic, their mother used a web-based pill identifier and discovered that the pills dispensed by the pharmacy were 200 mg clozapine tablets, not the cimetidine that had been prescribed. Ingestion was confirmed with an elevated serum clozapine concentration in the older child of 17 mcg/L at 85 hours post-ingestion (adult therapeutic range: 350-600 mcg/L). Both children had complete resolution of their symptoms 4 days following the ingestion with supportive care alone. DISCUSSION/CONCLUSIONS:We report two cases of pediatric clozapine toxicity due to a pharmacy dispensing error. The error was due, in part, to similarly named medications being stored adjacent to each other on a shelf. Dispensing errors are not rare occurrences and their root causes are multi-factorial. This case demonstrates the importance of reducing such errors, particularly for medications with potential for severe toxicity.

We report 2 pediatric patients who had acute overdoses of the direct oral anticoagulants medications. Both patients were managed conservatively; neither required reversal agents or blood products nor had any major or minor bleeding events. With therapeutic usage of direct oral anticoagulants, routine coagulation studies typically are considered insufficient measures of anticoagulation and the preferred chromogenic anti-Factor Xa assay is recommended but not widely available. Using a routine hybrid heparin anti-Factor Xa assay, 1 patient demonstrated a strong linear correlation up to a serum rivaroxaban concentration of 940 ng/mL.

BACKGROUND/UNASSIGNED:Severe acetaminophen (APAP) poisoning can result in fulminant hepatic failure and abnormal tests of coagulation. Although the international normalized ratio (INR) may be elevated, the actual hemostatic status of patients with APAP-induced hepatotoxicity is unknown. Few studies exist investigating the clinical use of thromboelastography (TEG) to evaluate the hemostatic status in the setting of APAP-induced hepatotoxicity. METHODS/UNASSIGNED:We performed a retrospective review of patients who were admitted for APAP toxicity and received TEG testing at a single transplant center. RESULTS/UNASSIGNED:Nine patients had detectable APAP concentrations and exhibited elevated aspartate and alanine aminotransferase activities. Seven had thrombocytopenia. TEG revealed a decreased median alpha angle and maximum amplitude but other values were within the normal reference range. DISCUSSION/UNASSIGNED:Based on our study of APAP-induced hepatotoxicity, TEG showed a decreased rate of fibrin formation and cross-linking, as well as reduced clot strength. These findings suggest that patients with APAP-induced hepatotoxicity and thrombocytopenia have a theoretically increased bleeding risk as demonstrated by both elevated INR and abnormal TEG values. However, these TEG findings are more likely related to thrombocytopenia rather than directly to APAP-induced hepatotoxicity. Further studies should be performed to elucidate the potential role of TEG in various stages of APAP-induced hepatotoxicity.

BACKGROUND:histamine receptor antagonist, is a commonly used nonprescription medication that is used for the treatment of allergy, as a sleep aid, or combined with cough and cold remedies. Naproxen, a nonsteroidal anti-inflammatory drug (NSAID), is used commonly for analgesia. Although most cases of diphenhydramine or naproxen overdose require excellent supportive care only, meticulous attention should be given to cardiovascular and neurologic status. CASE REPORT/METHODS:A 22-year-old woman presented with altered mental status secondary to intentional ingestion of 240 combination caplets of naproxen sodium 220 mg and diphenhydramine hydrochloride 25 mg. While in the emergency department, she manifested a wide-complex tachycardia in the setting of hypotension that required repeated administration of sodium bicarbonate to overcome the sodium channel blockade caused by diphenhydramine. Aggressive potassium repletion was performed simultaneously. Her clinical course was complicated by status-epilepticus that required intubation. Orogastric lavage was performed, which returned blue pill slurry consistent with the ingested caplets. The patient was extubated on hospital day 2 and transferred to psychiatry thereafter. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: In light of recent social media trends, such as the "Benadryl challenge" and its widespread availability, emergency providers should be familiar with diphenhydramine toxicity, especially the life-threatening neurologic consequences and risk of cardiovascular collapse. NSAIDs, such as naproxen, and other nonprescription analgesics are becoming more and more important in light of the current opioid crisis. There should be an emphasis on understanding these medications and their potential implications when taken in overdose.