Episode 967: Dilutional Hyponatremia
Emergency Medical Minute
Contributor: Taylor Lynch, MD Educational Pearls: Dilutional Hyponatremia: Occurs when there is an excess of free water relative to sodium in the body. Causes a falsely low sodium concentration without a true change in total body sodium. Commonly seen in DKA: Hyperglycemia raises plasma osmolality. Water shifts from the intracellular to extracellular space. This dilutes serum sodium, creating apparent hyponatremia. Corrected sodium calculation: Use tools like MDCALC, or apply this formula: Add 1.6 mEq/L to the measured sodium for every 100 mg/dL increase in glucose above 100. Clinical...
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EMSAC 2024
Emergency Medical Minute
Contributors: Col. (Dr.) Stacy Shackelford Dr. Sean Keenan Paramedic Alan Moreland Dr. Chris Tems Kara Napolitano From military-inspired trauma protocols to behavioral health alternatives and cardiac resuscitation, EMS is evolving fast. Our Medical Minutes from EMSAC highlight the growing need for prehospital providers to think critically, act quickly, and adapt to new approaches in trauma, crisis response, and patient advocacy. Educational Pearls: What was covered & recorded at EMSAC 2024 by EMM? Col. (Dr.) Stacy Shackelford, U.S. Air Force trauma surgeon and Director of the Joint Trauma...
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Episode 966: Acetaminophen Toxicity
Emergency Medical Minute
Contributor: Jorge Chalit-Hernandez, OMS4 Educational Pearls: What is the toxic dose of acetaminophen? 7.5 grams, in an adult. The safe daily limit is 4 grams in an adult with a normally functioning liver. This is equivalent to fifteen 500mg pills. What are the symptoms of acetaminophen toxicity? First 24 hours, symptoms are non-specific e.g. nausea, vomiting, lack of appetite. Can also be asymptomatic. 24-72 hours, hepatotoxicity occurs (causing yellow skin, pruritus, abdominal pain, bleeding, and confusion) Fulminant liver failure at 72-96 hours Liver function tests (LFTs) peak at 72-96...
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Episode 965: Oxygen Administration in Trauma Patients
Emergency Medical Minute
Contributor: Aaron Lessen, MD Educational Pearls: Many trauma patients are placed on oxygen via non-rebreather A large, multicenter, controlled trial evaluated the outcomes of oxygen administration in trauma patients Patients were randomized to two groups 1. 8-hour restrictive oxygen strategy: only receiving oxygen when the patient’s saturation dropped below 94% 2. 8-hour liberal oxygen strategy: 12-15 liters of oxygen per minute or fraction of inspired oxygen of 0.6-1.0 The study evaluated rates of death or major respiratory complications at 30 days There was no statistical difference...
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Episode 964: Ketamine & Midazolam for Prehospital Seizure Management
Emergency Medical Minute
Contributor: Aaron Lessen, MD Educational Pearls: Prehospital seizures are typically managed with intramuscular midazolam (Versed) Seizures theoretically involve the NMDA pathway, and ketamine is a potent NMDA antagonist A recent retrospective cohort study analyzed a Florida EMS protocol that uses ketamine in seizures refractory to midazolam One group received two doses of midazolam for seizure control The other group received a dose of midazolam followed by a dose of ketamine After matching, 82% of the midazolam-only group patients had resolution of convulsions prior to ED arrival 94.4%...
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Episode 963: Antihypertensives and Emergency Room Considerations
Emergency Medical Minute
Contributor: Alec Coston, MD Educational Pearls: For patients presenting to the emergency room with hypertension, clinicians should determine if it is isolated and uncomplicated, or involves comorbidities with more complex underlying pathophysiology. For uncomplicated and isolated hypertension, first-line treatment is thiazide diuretics. How do thiazide diuretics work to treat hypertension? Thiazide diuretics work by blocking sodium and chloride resorption in the kidneys. “Where sodium goes, water follows,” thus promoting diuresis and lowering blood pressure. Examples...
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Episode 962: HEART Score
Emergency Medical Minute
Contributor: Taylor Lynch, MD Educational Pearls: How do we risk-stratify chest-pain patients? One option is the HEART score This score predicts a patient’s 6-week risk of a major adverse cardiac event. Ex. Cath procedure, CABG, PCI, death H stands for History Ask 1) Was the patient diaphoretic? 2) Did they have nausea and/or vomiting? 3) Did the pain radiate down the right or left arm? 4) Was it exertional? Yes to one = one point. Two or more = two points. E stands for EKG One point for left ventricular hypertrophy, t-wave inversions, new bundle-branch blocks. No points for first...
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Episode 961: Cell Phone Sign
Emergency Medical Minute
Contributor: Aaron Lessen, MD Educational Pearls: A prospective study at the Mayo Clinic Rochester was conducted to examine whether patients actively using their phones on initial assessment in the ED was associated with higher discharge rates The study included 292 patients, and only about 15% of patients were on their phone The patients on their phone tended to be a younger demographic Scribes were trained to record the data during their shifts The results did show that patients on their phone have a higher rate of discharge 94% chance of discharge if the patient is on their phone 64%...
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Episode 960: Frank's Sign - A Marker for Coronary Artery Disease
Emergency Medical Minute
Contributor: Travis Barlock MD Educational Pearls Frank’s sign is a curious physical exam finding first described in the literature in 1973 Bilateral earlobe creases are recognized as a marker of coronary artery disease and cerebrovascular disease Some studies have found an increase in all-cause mortality in patients with bilateral diagonal earlobe creases The pathophysiology is still not fully understood One 2020 study found histopathological changes associated with diagonal earlobe creases, potentially linking them via a model of hypoxia/reoxygenation References Elliott WJ,...
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Episode 959: The KLM Flight Disaster and Lessons in Healthcare Communication
Emergency Medical Minute
Contributor: Taylor Lynch, MD Educational Pearls: The KLM Flight Disaster, also known as the Tenerife Airport Disaster, occurred on 27 March 1977. It involved the collision of two Boeing 747 passenger jets from KLM and Pan Am Airlines, resulting in 583 fatalities. What fell through the cracks to cause this incident? The captain of the KLM flight believed he had received clearance from air traffic control to take off, when in fact he had not. This captain was one of the most senior pilots in the organization, and the culture often saw senior pilots as infallible and not to be questioned....
info_outlineContributor: Jorge Chalit-Hernandez, OMS3
Educational Pearls:
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Serotonin syndrome occurs most commonly due to the combination of monoamine oxidase inhibition with concomitant serotonergic medications like SSRIs
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Examples of unexpected monoamine oxidase inhibitors
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Linezolid - a last-line antibiotic reserved for patients with true anaphylaxis to penicillins and cephalosporins
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Methylene blue - not mentioned in the podcast due to its uncommon usage for methemoglobinemia
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Other medications that can interact with SSRIs to cause serotonin syndrome
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Dextromethorphan - primarily an anti-tussive at sigma opioid receptors that also has serotonin reuptake inhibition
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Clinical presentation of serotonin syndrome
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Altered mental status
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Autonomic dysregulation leading to hypertension (most common), hypotension, and tachycardia
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Hyperthermia
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Neuromuscular hyperactivity - tremors, myoclonus, and hyperreflexia
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Hunter Criteria (high sensitivity and specificity for serotonin syndrome):
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Spontaneous clonus
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Inducible clonus + agitation or diaphoresis
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Ocular clonus + agitation or diaphoresis
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Tremor + hyperreflexia
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Hypertonia, temperature > 38º C, and ocular or inducible clonus
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Management of serotonin syndrome
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Primarily supportive - benzodiazepines can help treat hypertension, agitation, and hyperthermia. Patients often require repeated and higher dosing of benzodiazepines
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Avoid antipyretics to treat hyperthermia since the elevated temperature is due to sustained muscle contraction and not central temperature dysregulation
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In refractory patients, cyproheptadine (a 5HT2 antagonist) may be used as a second-line treatment
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Patients with temperatures > 41.1º C or 106º F require medically induced paralysis and intubation to control their temperature
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References
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Boyer EW, Shannon M. The serotonin syndrome [published correction appears in N Engl J Med. 2007 Jun 7;356(23):2437] [published correction appears in N Engl J Med. 2009 Oct 22;361(17):1714]. N Engl J Med. 2005;352(11):1112-1120. doi:10.1056/NEJMra041867
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Dunkley EJ, Isbister GK, Sibbritt D, Dawson AH, Whyte IM. The Hunter Serotonin Toxicity Criteria: simple and accurate diagnostic decision rules for serotonin toxicity. QJM. 2003;96(9):635-642. doi:10.1093/qjmed/hcg109
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Ramsay RR, Dunford C, Gillman PK. Methylene blue and serotonin toxicity: inhibition of monoamine oxidase A (MAO A) confirms a theoretical prediction. Br J Pharmacol. 2007;152(6):946-951. doi:10.1038/sj.bjp.0707430
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Schwartz AR, Pizon AF, Brooks DE. Dextromethorphan-induced serotonin syndrome. Clin Toxicol (Phila). 2008;46(8):771-773. doi:10.1080/15563650701668625
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Thomas CR, Rosenberg M, Blythe V, Meyer WJ 3rd. Serotonin syndrome and linezolid. J Am Acad Child Adolesc Psychiatry. 2004;43(7):790. doi:10.1097/01.chi.0000128830.13997.aa
Summarized & Edited by Jorge Chalit, OMS3