How to Build a Low-Cost Video-Assisted Laryngoscopy Suite for Airway Management Training.

Audience: This suite of borescope laryngoscopes is designed to instruct emergency medicine residents and sub-interns in video-assisted airway management. Background: Skillful and confident airway management is one of the markers of a strong emergency medicine physician.1 Video-assisted airway management is a necessary skill, particularly in the setting of difficult airways and cervical spine immobilization.2,3 However, the idea of learning airway management "by doing" is high-risk and mistakes can have devastating implications on patient outcomes. Fortunately, high-fidelity medical simulation tools have been developed to address this dilemma, allowing a safe environment for providers to practice their airway management skills.4,5 These tools, while undeniably useful, are limited in their scope; they are often designed for clinical rather than educational use, and are proprietary and expensive.6,7Video laryngoscopes approved for patient use are difficult to implement widely in educational settings due to cost or because they cannot be removed from a designated area. Clinical video laryngoscopy suites typically cost 2,000 - 6,000 US dollars. Additionally, the video images can only be viewed on a local small screen rather than a television or projector. This means that the number of learners is limited by space around the small laryngoscope screen. These cost and space barriers may be especially pronounced in low resource or non-traditional learning environments. Educational Objectives: Using an anatomically accurate airway simulator, by the end of a 20-30-minute instructional session, learners should be able to: 1) Understand proper positioning and use the video laryngoscope with dexterity, 2) identify airway landmarks via the video screen, and 3) demonstrate ability to intubate a simulated airway. Educational Methods: We developed a low-cost borescope laryngoscope for airway simulation training. Using this device, learners should be able to identify airway landmarks and successfully intubate a simulated airway. The borescope laryngoscope, a novel device which employs the camera-end of a video borescope and a single-use VL blade, was used by learners during high-fidelity airway simulation. Learners were residents or medical students undergoing airway training in case-based simulation, or in airway-management procedure stations. Research Methods: The borescope laryngoscopes were used during dedicated airway training in place of their medical device counterparts. During case-based simulation sessions involving airway management, 32 residents and 20 medical students used the borescope laryngoscope. During dedicated airway management procedure stations, 12 medical students used the borescope laryngoscope. Learners were instructed to perform endotracheal intubation and fully visualize critical structures before passing the tube. Successful intubation was defined as the ability to pass the tube independently or with the help of the instructor. Results: The borescope laryngoscope proved effective at video visualization of critical structures. Compared to official medical equipment, the VL borescope similarly allowed for visualization of a Cormack-Lehane Grade 1 view. Learners were able to visualize the airway anatomy and successfully pass the ET tube on each pass either independently or with the help of the instructor. Discussion: The development of this airway-training tool was effective and less expensive than medical grade versions. Our group of learners successfully visualized essential anatomy and passed an endotracheal tube (ED tube) through the vocal cords. The borescope laryngoscope offers a comparable user experience at a much lower cost. The devices also allowed instructors to teach video laryngoscopy without depending on clinical equipment. Widespread use may allow for expansion of airway simulation training while maintaining a high-fidelity learner experience. Topics: Video laryngoscopy, borescope, improvised equipment, airway training.

The Goiânia incident, the semiotics of danger, and the next 10,000 years.

THE GOIÂNIA INCIDENT: In September 1987, two men in Goiânia, Brazil, discovered an abandoned international standard capsule containing less than 100 g of cesium-137 chloride. The material was unguarded, and the warning systems were inadequate and inscrutable. The men took the capsule and sold it for scrap, and within days the city would be contaminated with highly radioactive material. Within weeks, 112,000 individuals would be screened for radioactive contamination, 249 would be exposed to radioactive materials, 46 would receive medical treatment for radioactive contamination, and four would die from acute radiation sickness. The citywide radioactive contamination occurred, in part, due to arbitrary and unfamiliar written warning systems. The individuals who discovered the cesium-137 capsule were illiterate and unfamiliar with the radiation trefoil logo, which was first used in 1946 in California, United States of America. As a result, written language and visual symbols were useless warnings against the dangerous contents of the capsule. MANAGEMENT OF CESIUM-137 EXPOSURE IN 2023: Cesium-137 enters the body through ingestion or inhalation. This isotope emits beta and gamma radiation, both forms of ionizing radiation which damage living tissues. The radiation dose lethal to 50% of an exposed population within 60 days (LD50/60) is approximately 3.5 to 4 Gray (Gy) without medical intervention. However, this dose increases to around 6-7 Gy when medical support is provided, which typically includes antibiotics, blood transfusions, granulocyte-macrophage colony-stimulating factor, and Prussian blue. Prussian blue binds to cesium, thereby facilitating its elimination from the body. LESSONS LEARNED REGARDING RADIOACTIVE WASTE DISPOSAL AND THE NEXT 10,000 YEARS: The radiological disaster in Goiânia was due in large part to the failures of various agencies to warn of danger and minimize access to radioactive material. Barriers to risk communication included a lack of a universal semiotic language regarding radioactive hazards, which was compounded by the illiteracy of the scrappers and their inability to recognize the radioactivity warning trefoil. There is no society in which every member understands written language or recognizes every symbol. Given that the teletherapy unit was abandoned in an urban environment, there were no administrative or engineering controls in place to prevent human beings from becoming exposed to radioactive material. CONCLUSIONS: As little as 100 g of highly radioactive material, such as cesium-137, may lead to massive environmental contamination, fatalities and permanent disability due to acute radiation sickness, wreak havoc, and disrupt society on a scale that is challenging for public health officials to manage. Thousands of tons of radioactive materials from the waste products of nuclear weapons and power plant manufacture will have to be stored for at least 100,000 years to prevent danger to human life and society. Public health officials and governments must build systems to keep humans safe and physically isolated from these radioactive materials for as long as possible.

The powder in the basement: how an unlabeled poison inspired federal legislative change.

The Oregon State Hospital, first established in 1862 as the Oregon Insane Asylum, was a state funded mental health institution that provided care and housing for a large and diverse patient population. In December 1941, the United States formally entered World War II. As wartime production and demands increased over the course of 1941 and into 1942, resources became more limited and budgets tightened. On the evening of November 18, 1942 hundreds of patient suddenly fell ill and dozens died. Initially it was unclear if this was an accident, a mass murder, or an act of sabotage related to the war effort. The investigation revealed that the casualties fell victim to a mass poisoning. Over the next months to years, there would be new State and Federal laws intended to prevent something like this from ever happening again.

Dosing Heat: Expected Core Temperature Change with Warmed or Cooled Intravenous Fluids.

Emergent modification of a patient's body temperature is crucial in certain disease or injury states. Advanced targeted temperature management techniques such as central venous catheter devices are not universally available, however, virtually all medical centers have access to intravenous fluids. This study approximates the change in body temperature for a given volume of room temperature, chilled, or heated isotonic crystalloid bolus. Using thermodynamic principles, a mathematical model was created to approximate change in body core temperature in response to a given volume and temperature of intravenous fluid. The model assumes rapid fluid infusion and the previously published specific heat capacity of the human body of 3.47 J/kg · °C. Values were calculated under conditions of varying body temperatures from profound hypothermia to hyperthermia (18°C-45°C). Various crystalloid temperatures representing iced, room temperature, and warmed (4°C, 20°C, 42°C) were used in the calculations. Each 30 mL/kg dose of 20°C crystalloid is expected to cool a hyperthermic (38°C-45°C) patient by 0.6°C-0.9°C. Each 30 mL/kg dose of 4°C crystalloid is expected to cool a hyperthermic (38°C-45°C) patient by 1.2°C-1.4°C. Each dose of 42°C crystalloid is expected to warm a hypothermic patient by 0.2°C-0.8°C. Using the results in this study, clinicians may roughly estimate the effect of temperature management with varying doses of intravenous fluids and thus assess the benefits of this technique. Risk should be evaluated based on inevitable coadministered volume and electrolytes. Individuals with volume-sensitive conditions such as heart, liver, or kidney failure deserve particular attention. Based on a mathematical model, typical expected core temperature change is about 0.2°C-1.4°C per 30 mL/kg crystalloid bolus, depending on patient and fluid temperature.

Botulism.

Audience: This simulation is targeted to emergency medicine residents and medical students. This case focuses on the diagnosis and management of botulism toxicity, while highlighting the logistical complications of botulism toxicity. Introduction: Botulism is a potentially life-threatening emergency that often presents with subtle symptoms, which can progress to paralysis and respiratory failure. A descending flaccid paralysis is typical, initially affecting smaller muscles such as oculomotor, then larger facial muscles. 1,2 Early indications of respiratory compromise are important to recognize. It is important for emergency medicine physicians to be familiar with botulism and recognize the presentation quickly to safely treat the patient. Clinical findings may include: dilated pupils, diplopia, xerostomia, dysphagia, and nausea and vomiting. 3 Treatment priorities include assessment and management of the airway, close monitoring, and coordinating with local agencies to obtain botulinum antitoxin.1. Educational Objectives: By the end of this simulation learners will be able to: 1) develop a differential for descending paralysis and recognize the signs and symptoms of botulism; 2) understand the importance of consulting public health authorities to obtain botulinum antitoxin in a timely fashion; 3) recognize that botulism will progress during the time period antitoxin is obtained. Early indications of respiratory compromise are expected to worsen during this time window.Secondary learning objectives include: 4) employ advanced evaluation for neurogenic respiratory failure such as physical examination, negative inspiratory force (NIF), forced vital capacity (FVC), and partial pressure of carbon dioxide (pCO2), 5) discuss and review the pathophysiology of botulism, 6) discuss the epidemiology of botulism. Educational Methods: This simulation was conducted using a high-fidelity mannequin with intubating capabilities and real-time vital sign monitoring. Following the simulation, the participants underwent a debriefing session and discussion on botulism. This case was designed as a high-fidelity simulation, but it can be adapted to a low-fidelity simulation or case discussion. Research Methods: Following the simulation and debriefing session, participants were provided with a survey to rate the simulation and provide feedback to instructors. Participants were asked open-ended questions about the strengths and areas of improvement of the case, and were asked to rate how they valued the learning content of the case on a 5-point scale. Results: Emergency medicine residents expressed positive feedback on the scenario. The residents appreciated the change in clinical course of the patient over time as well as the presentation of botulism.Discussion: This simulation is an effective way of teaching about botulism to emergency medicine residents. We used a primary nurse asking questions to progress the case and stimulate the learners to think about certain specific aspects of the case, such as the patient's weakness or disposition.Topics: Toxicology, botulism, emergency medicine, medical simulation.

Extracorporeal membrane oxygenation use in poisoning: a narrative review with clinical recommendations.

CONTEXT: Poisoning may lead to respiratory failure, shock, cardiac arrest, or death. Extracorporeal membrane oxygenation (ECMO) may be used to provide circulatory support, termed venoarterial (VA) ECMO; or respiratory support termed venovenous (VV) ECMO. The clinical utility of ECMO in poisoned patients remains unclear and guidelines on its use in this setting are lacking. OBJECTIVES: To perform a literature search and narrative review on the use of ECMO in poisonings. Additionally, to provide recommendations on the use of ECMO in poisonings from physicians with expertise in ECMO, medical toxicology, critical care, and emergency medicine. METHODS: A literature search in Ovid MEDLINE from 1946 to October 14, 2020, was performed to identify relevant articles with a strategy utilizing both MeSH terms and adjacency searching that encompassed both extracorporeal life support/ECMO/Membrane Oxygenation concepts and chemically-induced disorders/toxicity/poisoning concepts, which identified 318 unique records. Twelve additional manuscripts were identified by the authors for a total of 330 articles for screening, of which 156 were included for this report. NARRATIVE LITERATURE REVIEW: The use of ECMO in poisoned patients is significantly increasing over time. Available retrospective data suggest that patients receiving VA ECMO for refractory shock or cardiac arrest due to poisoning have lower mortality as compared to those who receive VA ECMO for non-poisoning-related indications. Poisoned patients treated with ECMO have reduced mortality as compared to those treated without ECMO with similar severity of illness and after adjusted analyses, regardless of the type of ingestion. This is especially evident for poisoned patients with refractory cardiac arrest placed on VA ECMO (termed extracorporeal cardiopulmonary resuscitation [ECPR]). INDICATIONS: We suggest VA ECMO be considered for poisoned patients with refractory cardiogenic shock (continued shock with myocardial dysfunction despite fluid resuscitation, vasoactive support, and indicated toxicologic therapies such as glucagon, intravenous lipid emulsion, hyperinsulinemia euglycemia therapy, or others), and strongly considered for patients with cardiac arrest in institutions which are structured to deliver effective ECPR. VV ECMO should be considered in poisoned patients with ARDS or severe respiratory failure according to traditional indications for ECMO in this setting. CONTRAINDICATIONS: Patients with pre-existing comorbidities with low expected survival or recovery. Relative contraindications vary based on each center's experience but often include: severe brain injury; advanced age; unrepaired aortic dissection or severe aortic regurgitation in VA ECMO; irreversible organ injury; contraindication to systemic anticoagulation, such as severe hemorrhage. CONCLUSIONS: ECMO may provide hemodynamic or respiratory support to poisoned patients while they recover from the toxic exposure and metabolize or eliminate the toxic agent. Available literature suggests a potential benefit for ECMO use in selected poisoned patients with refractory shock, cardiac arrest, or respiratory failure. Future studies may help to further our understanding of the use and complications of ECMO in poisoned patients.

Methemoglobinemia associated with massive acetaminophen ingestion: a case series.

Background: Acetaminophen is a common pharmaceutical ingestion reported to US poison centers. In overdose, toxic metabolites are known to cause hepato- and nephrotoxicity. While G6PD deficiency may be a risk factor for methemoglobin production in the setting of acetaminophen overdose, it is rarely reported in patients who do not have this condition.Methods: We present two cases of methemoglobinemia following massive acetaminophen ingestion with no known history of G6PD deficiency or other substances known to induce methemoglobinemia. The two cases had peak methemoglobin measurements of 32% and 12% respectively, and both were treated with methylene blue.Discussion: A number of mechanisms may be involved in production of methemoglobin in the setting of massive acetaminophen ingestion including NAPQI-induced oxidation, depletion of glutathione stores, and production of oxidant-metabolites including paraaminophenol. While it is unlikely that the majority of acetaminophen overdoses result in any clinically significant methemoglobinemia, massive acetaminophen overdose may be complicated by development of methemoglobinemia.Conclusion: Physicians should be aware of the possibility that massive acetaminophen ingestion may be complicated by methemoglobinemia in rare instances. Further studies should aim to characterize the metabolic pathways leading to possible methemoglobinemia in humans after large acetaminophen ingestions.

Flualprazolam: Report of an Outbreak of a New Psychoactive Substance in Adolescents.

Flualprazolam is a nonregistered drug in the benzodiazepine family and constitutes a new psychoactive substance (NPS). Since 2014, a growing number of designer benzodiazepines have become available over the Internet and on the counterfeit drug market. In June 2019, a cluster of patients intoxicated with flualprazolam was identified by the Oregon Poison Center. As an emerging drug of abuse, the clinical characteristics of flualprazolam have been poorly characterized thus far. Over a one-week period, 6 teenagers presented to local emergency departments after ingesting illegally obtained counterfeit alprazolam, which led to sedation. Other symptoms included slurred speech, confusion, and mild respiratory depression. All 6 patients had resolution of their symptoms within 6 hours of ingestion. Blood and urine samples, as well as a tablet fragment, were obtained from 3 patients. The tablet and biological samples were analyzed by using liquid chromatography-quadrupole time-of-flight mass spectrometry and were found to contain the NPS flualprazolam without other drugs or intoxicants. With this case series, we add to the medical literature a clinical description of an emerging drug of abuse. Flualprazolam appears to share the clinical properties of other benzodiazepines. As flualprazolam and other NPSs become more common, physicians must be aware of their availability and characteristics. Sedation lasting <6 hours was observed in 6 of 6 patients exposed to flualprazolam. No effects that would be unexpected from benzodiazepine intoxication were seen among the patients. Specifically, none developed prolonged symptoms or required intubation and mechanical ventilation, ICU admission, or antidotal therapy.

Do Patients Die with or from Metformin-Associated Lactic Acidosis (MALA)? Systematic Review and Meta-analysis of pH and Lactate as Predictors of Mortality in MALA.

OBJECTIVES: Metformin-associated lactic acidosis (MALA) may occur after acute metformin overdose, or from therapeutic use in patients with renal compromise. The mortality is high, historically 50% and more recently 25%. In many disease states, lactate concentration is strongly associated with mortality. The aim of this systematic review and meta-analysis is to investigate the utility of pH and lactate concentration in predicting mortality in patients with MALA. METHODS: We searched PubMed, EMBASE, and Web of Science from their inception to April 2019 for case reports, case series, prospective, and retrospective studies investigating mortality in patients with MALA. Cases and studies were reviewed by all authors and included if they reported data on pH, lactate, and outcome. Where necessary, authors of studies were contacted for patient-level data. Receiver operating characteristic (ROC) curves were generated for pH and lactate for predicting mortality in patients with MALA. RESULTS: Forty-four studies were included encompassing 170 cases of MALA with median age of 68.5 years old. Median pH and lactate were 7.02 mmol/L and 14.45 mmol/L, respectively. Overall mortality was 36.2% (95% CI 29.6-43.94). Neither lactate nor pH was a good predictor of mortality among patients with MALA. The area under the ROC curve for lactate and pH were 0.59 (0.51-0.68) and 0.43 (0.34-0.52), respectively. CONCLUSION: Our review found higher mortality from MALA than seen in recent studies. This may be due to variation in standard medical practice both geographically and across the study interval, sample size, misidentification of MALA for another disease process and vice versa, confounding by selection and reporting biases, and treatment intensity (e.g., hemodialysis) influenced by degree of pH and lactate derangement. The ROC curves showed poor predictive power of either lactate or pH for mortality in MALA. With the exception of patients with acute metformin overdose, patients with MALA usually have coexisting precipitating illnesses such as sepsis or renal failure, though lactate from MALA is generally higher than would be considered survivable for those disease states on their own. It is possible that mortality is more related to that coexisting illness than MALA itself, and many patients die with MALA rather than from MALA. Additional work looking solely at MALA in healthy patients with acute metformin overdose may show a closer relationship between lactate, pH, and mortality.

Utility of 2-Pyridine Aldoxime Methyl Chloride (2-PAM) for Acute Organophosphate Poisoning: A Systematic Review and Meta-Analysis.

Organophosphates (OP) account for the majority of pesticide-related unintentional or intentional poisonings in lower- and middle-income countries. The therapeutic role of atropine is well-established for patients with acute OP poisoning. The benefit of adding 2-pyridine aldoxime methyl chloride (2-PAM), however, is controversial. We performed a systematic review and meta-analysis of available randomized controlled trials (RCT) to compare 2-PAM plus atropine in comparison to atropine alone for acute OP poisoning. We searched PubMed, EMBASE, and SCOPUS up to March 2017. The Cochrane review handbook was used to assess the risk of bias. Data were abstracted and risk ratios (RR) were calculated for mortality, rate of intubation, duration of intubation, intermediate syndrome, and complications such as hospital-acquired infections, dysrhythmias, and pulmonary edema. We found five studies comprising 586 patients with varying risks of bias. The risk of death (RR = 1.5, 95% CI 0.9-2.5); intubation (RR = 1.3, 95% CI 1.0-1.6); intermediate syndrome (RR = 1.6, 95% CI 1.0-2.6); complications (RR = 1.2, 95% CI 0.8-1.8); and the duration of intubation (mean difference 0.0, 95% CI - 1.6-1.6) were not significantly different between the atropine plus 2-PAM and atropine alone. Based on our meta-analysis of the available RCTs, 2-PAM was not shown to improve outcomes in patients with acute OP poisoning.

Correction to: Utility of 2-Pyridine Aldoxime Methyl Chloride (2-PAM) for Acute Organophosphate Poisoning: A Systematic Review and Meta-Analysis.

The names of coauthors Roshanak Benabbas and and Ian S. deSouza were given incorrectly (as "Roshnak Benabbas" and "Ian de Souza", respectively) in this article as originally published.