Blog and Podcast Watch : Toxicology

Introduction: The WestJEM Blog and Podcast Watch presents high-quality open-access educational blogs and podcasts in emergency medicine based on the ongoing Academic Life in Emergency Medicine (ALiEM) Approved Instructional Resources (AIR) and AIR-Professional (Pro) series. Both series critically appraise open-access educational blogs and podcasts in EM using an objective scoring instrument. This installment of the blog and podcast watch series curated and scored relevant posts in the specific topic of toxicology emergencies from the AIR-Pro Series.


INTRODUCTION
Despite the rapid rise in social media educational content on blogs and podcasts, especially in emergency medicine (EM), 1 there has only been preliminary progress in helping educators and learners identify quality Zaver et al.
ALiEM Blog and Podcast Watch: Toxicology programs, however, were often unsure how to identify quality online resources specifically for asynchronous learning and III credit.
To address this need, the Approved Instructional Resources (AIR) Series 6 and AIR-Professional (Pro) Series were created in 2014 and 2015, respectively, by Academic Life in Emergency Medicine (ALiEM) to help EM residency programs identify quality online content specifically on social media. Using an expert-based, crowdsourced approach, these two programs identify trustworthy, high-quality educational blog and podcast content. The intended audience for the AIR series is EM junior residents, and for the AIR-Pro Series is the EM advanced practitioner. This blog and podcast watch series on WestJEM presents annotated summaries from the AIR and AIR-Pro Series.
This installment from the AIR-Pro Series summarizes the best scoring social media educational resources on specific topics within toxicology emergencies.

Question Identification
The AIR-Pro Series is a continuously building curriculum covering a new subject area every two months. For each area, eight EM chief residents from different U.S. residency programs on the ALiEM-Pro editorial board identify 3-5 focused, advanced-level clinical queries within the featured subject area. The topics for this installment included the following: 1. Flumazenil in benzodiazepine overdose 2. Acetaminophen -drawing and timing of levels 3. Opioid overdoses 4. Acetaminophen toxicity related to liver transplant 5. Salicylates and hemodialysis

Inclusion and exclusion criteria
All available blog posts and podcasts on these five topics were identified using two custom EM search engines: FOAMsearch.net and FOAMSearcher. Blog posts and podcasts written in English and identified by key search terms were included for our scoring by our expert panel. Journal articles were excluded from the list.

Scoring
Extracted posts were scored by eight reviewers from the AIR-Pro editorial board, which is comprised of EM core faculty and chief residents from various U.S. institutions. The eight reviewers included five chief residents from the AIR-Pro editorial board as well as three EM faculty educators. The scoring instrument contains five measurement outcomes using seven-point Likert scales: recency, accuracy, educational utility, evidence based, and references (Table 1).

Data Analysis
An AIR-Pro endorsement is given to posts with a score of ≥28 (out of 35) points. Depending on the redundancy of the highest scoring posts, the best of these are then selected to address each pre-selected topic. An "honorable mention" label is also given to posts specifically felt to be worthwhile, accurate, unbiased, and educationally valuable for advanced clinicians by consensus of the AIR-Pro board. These posts must have scored ≥25 (out of 35) points.

RESULTS
A total of 31 blog posts and podcasts were initially included. Key educational pearls from the six highquality, AIR-Pro posts and four honorable mentions are summarized ( Table 2). This blog post discusses the incidence of seizures associated with the use of flumazenil in benzodiazepine overdose. It provides evidence that questions the long-held belief regarding the risk of seizures associated with the use of flumazenil.

Take home points
The post acknowledges that earlier studies documented a 13% incidence of seizures associated with the use of flumazenil; however, a number of recent studies put that rate at about 1%. Although the true incidence of seizures with the use of flumazenil cannot be precisely ascertained, it should be used with caution. The use of flumazenil is warranted for the following specific emergent situations in non-chronic benzodiazepine users: pediatric ingestions, iatrogenic toxicity, and a paradoxical response associated with a pure benzodiazepine overdose.

Hayes B. Utility of Pre-4-Hour Acetaminophen
Levels in Acute Overdose. ALiEM. (August 5th, 2015) https://www.aliem.com/2015/utility-of-pre-4-houracetaminophen-levels-in-overdoses/ Through a review of multiple studies addressing the utility of pre-four hour levels, the timing of acetaminophen levels are examined including the interpretation of these levels.

Take-home points
Undetectable levels drawn after one hour of ingestion suggest that it is unlikely that the four-hour level will be clinically significant. The Rumack-Matthew nomogram, however, can only be used with an adequate negative predictive value when acetaminophen levels are drawn four hours after ingestion. Emergency physicians should ALiEM Blog and Podcast Watch: Toxicology Zaver et al.

Take home points
Consider opioid ingestion in patients with toxidrome findings of miosis, central nervous system depression, respiratory depression, and consequences of prolonged hypoxia (seizures, dysrhythmias, brain injury). Do not give high doses of naloxone out of concern for precipitating Zaver et al.  withdrawal, unless the patient is in cardiac arrest. Naloxone has a shorter half-life than most long-acting opioids and will often need to be re-dosed. This is especially relevant in the patient who received one dose with significant response who is threatening to leave the department. Prior to discharge or admission it is also important to evaluate a patient for a possible intentional overdose requiring psychiatric evaluation, rhabdomyolysis or compartment syndrome due to prolonged unconsciousness, as well as for substance-abuse referral.

Cohn B, Schwarz E. Treat and Release vs. Observation After Naloxone for Opioid Overdose. EMJ Club Podcast 17. (November 24, 2014) http://emjclub. com/podcast/observation-after-naloxone
This 18-minute podcast uses a clinical case scenario to highlight the disposition considerations in the case of patients who overdose on opioids and received naloxone. Through a PubMed search, the podcast uses a journal club approach to analyze four articles on the topic.

Take home points
The literature supports a "treat and release" strategy for a specific set of patients who have overdosed on opioids. These patients must return to their pre-overdose baseline, be hemodynamically stable and alert, and understand the risks versus benefits of their medical condition prior to discharge. This strategy has not been tested in an overdose of long-acting opioids such as methadone. Thus, caution should be applied in its use in this scenario since rebound symptoms are common with long-acting opioids.

Toxicity. Life in the FastLane. (April 30, 2016) http:// lifeinthefastlane.com/ccc/liver-transplantation-forparacetamol-toxicity
This post is an overview of liver failure in the setting of acetaminophen (paracetamol) toxicity. Nickson outlines the details for identification of possible transplant candidates, utility of the King's College Criteria and research thus far on long-term outcomes of acute liver failure from toxicity.

Take home points
Trending a patient's serum salicylate levels is more important than a single value level. Furthermore, acidosis correlates with severity of illness. The goal of treatment is to maintain a serum pH of 7.50-7.55 by adding three ampules (50 mL each) of 8.4% sodium bicarbonate to one liter of 5% dextrose in water. Avoid intubation if possible, but if necessary give sodium bicarbonate prior and hyperventilate the patient after to maintain compensatory respiratory alkalosis. Emergent hemodialysis should be seriously considered for patients with serum salicylate levels >100 mg/dL, as well as for patients with any salicylate level plus severe symptoms such as central nervous system dysfunction, renal failure, cerebral/ pulmonary edema, or unexplained acid-based disturbance.

Nickson C. Paracetamol/Acetaminophen Overdose. Life in the FastLane. (Sept 3, 2010) http:// lifeinthefastlane.com/paracetamol-overdose/
This blog post summarizes the key pearls in the epidemiology, identification and management of acetaminophen overdose.

Take home points
Paracetamol/acetaminophen (APAP) is the most common medication taken in overdose and the number one cause of acute liver failure in the U.S. APAP toxicity is typically thought to occur in four stages although these symptoms and timeline are not always consistent. Activated charcoal was previously used in the setting of acute ingestion, but is much less effective after 1-2 hours after ingestion. N-acetylcysteine (NAC) is now the standard treatment. NAC promotes the non-toxic metabolism of acetaminophen and should be started within eight hours of ingestion for maximum efficacy. If the patient presents after eight hours from ingestion with a significant risk for toxicity, it is reasonable to start IV NAC without an acetaminophen level as the risks of waiting outweigh the mild side effects of the drug such as flushing or a rash. This blog post discusses how to dilute naloxone to provide better titration in reversing the signs and symptoms from an opioid overdose, without inducing symptoms of opioid withdrawal.

Take Home Points
In a 10-mL syringe, combine 9 mL of sterile normal saline and 1 mL of 0.4 mg/mL naloxone. This results in a 10 mL solution of 0.04 mg/mL naloxone. Label the syringe and administer 1-2 mL (equal to 0.04-0.08 mg) of naloxone every 60 seconds to achieve the desired clinical state.

Take Home Points
The toxic dose of acetaminophen in adults is >10 g or >200 mg/kg in 24 hours. The Rumack-Matthew nomogram is only validated for a single ingestion of acetaminophen; it is unreliable for multiple ingestions, delayed presentation, or modified release preparations. If a patient presents in the 8-24 hour period after the ingestion, obtain acetaminophen levels and liver enzymes to guide management, even if the patient is asymptomatic. For massive ingestions >30 g, higher doses of NAC may be necessary and will require expert consultation.

Take Home Points
A diagnostic pitfall is to rely solely on down trending salicylate levels alone. Down trending levels alone are not always reassuring for the patient's clinical course; be sure to monitor for signs of central nervous system (CNS) toxicity. Regarding management, patients are often hypovolemic, hypokalemic, and acidotic. Thus, ensure adequate fluid resuscitation, replace potassium levels to a goal of >4 mEq/L, and correct acidemia with sodium bicarbonate in dextrose 5% water (D5W) to a goal serum pH 7.45-7.55 to enhance elimination. Serum glucose levels should be maintained >150 mg/dL to prevent CNS-related hypoglycemia. If intubation is necessary, maintain preintubation minute ventilation to avoid worsening acidemia. Do not delay hemodialysis for those with serum levels >100 mg/dL or signs of significant toxicity.

CONCLUSION
The WestJEM Blog and Podcast Watch series serves to identify educational quality blogs and podcasts for EM clinicians through its expert panel using an objective scoring instrument. These social media resources are currently curated in the ALiEM AIR and AIR-Pro Series, originally created to address EM residency needs. These resources are herein shared and summarized to help clinicians filter the rapidly published multitude of blog posts and podcasts. While these lists are by no means a comprehensive analysis of the entire Internet for these topics, this series provides a post-publication accreditation and curation of recent, online content to identify and recommend high-quality educational social media content for the EM clinician.