Emergency Medical Minute Emergency Medical Minute

Contributor: Aaron Lessen MD
Educational Pearls:
Epinephrine is essential in the treatment of anaphylaxis, but is epinephrine dangerous from a cardiovascular perspective?
A 2024 study in the Journal of the American College of Emergency Physicians Open sought to answer this question.
Methods:
Retrospective observational study at a Tennessee quaternary care academic ED that analyzed ED visits from 2017 to 2021 involving anaphylaxis treated with IM epinephrine.
The primary outcome was cardiotoxicity
Results:
Out of 338 patients, 16 (4.7%) experienced cardiotoxicity. Events included ischemic EKG changes (2.4%), elevated troponin (1.8%), atrial arrhythmias (1.5%), ventricular arrhythmia (0.3%), and depressed ejection fraction (0.3%).
Affected patients were older, had more comorbidities, and often received multiple epinephrine doses.
Bottom line:
All adults presenting with anaphylaxis should be rapidly treated with epinephrine but monitored closely for cardiotoxicity, especially in patients with a history of hypertension and those who receive multiple doses.
These results are supported by a 2017 study that found that 9% (4/44) of older patients who received epinephrine for anaphylaxis had cardiovascular complications.
References
Kawano, T., Scheuermeyer, F. X., Stenstrom, R., Rowe, B. H., Grafstein, E., & Grunau, B. (2017). Epinephrine use in older patients with anaphylaxis: Clinical outcomes and cardiovascular complications. Resuscitation, 112, 53–58. https://doi.org/10.1016/j.resuscitation.2016.12.020
Pauw, E. K., Stubblefield, W. B., Wrenn, J. O., Brown, S. K., Cosse, M. S., Curry, Z. S., Darcy, T. P., James, T. E., Koetter, P. E., Nicholson, C. E., Parisi, F. N., Shepherd, L. G., Soppet, S. L., Stocker, M. D., Walston, B. M., Self, W. H., Han, J. H., & Ward, M. J. (2024). Frequency of cardiotoxicity following intramuscular administration of epinephrine in emergency department patients with anaphylaxis. Journal of the American College of Emergency Physicians open, 5(1), e13095. https://doi.org/10.1002/emp2.13095
Summarized by Jeffrey Olson MS2 | Edited by Meg Joyce & Jorge Chalit OMS II

Contributor: Aaron Lessen MD
Educational Pearls:
Opioid overdoses that are reversed with naloxone (Narcan), a mu-opioid antagonist, can precipitate acute withdrawal in some patients
Treatment of opioid use disorder with buprenorphine can also precipitate withdrawal
Opioid withdrawal symptoms include nausea, vomiting, diarrhea, and agitation
Buprenorphine works as a partial agonist at mu-opioid receptors, which may alleviate withdrawal symptoms
The preferred dose of buprenorphine is 16 mg
Treatment of buprenorphine-induced opioid withdrawal is additional buprenorphine
Adjunctive treatments may be used for other opioid withdrawal symptoms
Nausea with ondansetron
Diarrhea with loperamide
Agitation with hydroxyzine
References
1. Quattlebaum THN, Kiyokawa M, Murata KA. A case of buprenorphine-precipitated withdrawal managed with high-dose buprenorphine. Fam Pract. 2022;39(2):292-294. doi:10.1093/fampra/cmab073
2. Spadaro A, Long B, Koyfman A, Perrone J. Buprenorphine precipitated opioid withdrawal: Prevention and management in the ED setting. Am J Emerg Med. 2022;58:22-26. doi:10.1016/j.ajem.2022.05.013
Summarized by Jorge Chalit, OMSII | Edited by Meg Joyce & Jorge Chalit
 

Contributor: Travis Barlock MD
Educational Pearls:
How do you differentiate between compensated and decompensated cirrhosis?
Use the acronym VIBE to look for signs of being decompensated.
V-Volume
Cirrhosis can cause volume overload through a variety of mechanisms such as by increasing pressure in the portal vein system and the decreased production of albumin.
Look for pulmonary edema (dyspnea, orthopnea, wheezing/crackles, coughing up frothy pink sputum, etc.) or a tense abdomen.
I-Infection
The ascitic fluid can become infected with bacteria, a complication called Spontaneous Bacterial Peritonitis (SBP).
Look for abdominal pain, fever, hypotension, and tachycardia. Diagnosis is made with ascitic fluid cell analyses (polymorphonuclear neutrophils >250/mm3)
B-Bleeding
Another consequence of increased portal pressure is that blood backs up into smaller blood vessels, including those in the esophagus.
Over time, this increased pressure can result in the development of dilated, fragile veins called esophageal varices, which are prone to bleeding.
Look for hematemesis, melena, lightheadedness, and pale skin.
E-Encephalopathy
A failing liver also does not clear toxins which can affect the brain.
Look for asterixis (flapping motion of the hands when you tell the patient to hold their hands up like they are going to stop a bus)
Other complications to look out for.
Hepatorenal syndrome
Hepatopulmonary syndrome
References
Engelmann, C., Clària, J., Szabo, G., Bosch, J., & Bernardi, M. (2021). Pathophysiology of decompensated cirrhosis: Portal hypertension, circulatory dysfunction, inflammation, metabolism and mitochondrial dysfunction. Journal of hepatology, 75 Suppl 1(Suppl 1), S49–S66. https://doi.org/10.1016/j.jhep.2021.01.002
Enomoto, H., Inoue, S., Matsuhisa, A., & Nishiguchi, S. (2014). Diagnosis of spontaneous bacterial peritonitis and an in situ hybridization approach to detect an "unidentified" pathogen. International journal of hepatology, 2014, 634617. https://doi.org/10.1155/2014/634617
Mansour, D., & McPherson, S. (2018). Management of decompensated cirrhosis. Clinical medicine (London, England), 18(Suppl 2), s60–s65. https://doi.org/10.7861/clinmedicine.18-2-s60
Summarized by Jeffrey Olson MS2 | Edited by Meg Joyce & Jorge Chalit, OMS II
 

Contributor: Aaron Lessen MD
Educational Pearls:
Lorazepam (Ativan) is dosed at 0.1 mg/kg up to a maximum of 4 mg in status epilepticus
Some ED protocols only give 2 mg initially
The maximum recommended dose of levetiracetam (Keppra) is 60 mg/kg or 4.5 g
In one retrospective study, only 50% of patients received the correct dose of lorazepam
For levetiracetam, it was only 35% of patients
Underdosing leads to complications
Higher rates of intubations
More likely to progress to refractory status epilepticus
References
1. Cetnarowski A, Cunningham B, Mullen C, Fowler M. Evaluation of intravenous lorazepam dosing strategies and the incidence of refractory status epilepticus. Epilepsy Res. 2023;190(November 2022):107067. doi:10.1016/j.eplepsyres.2022.107067
2. Sathe AG, Tillman H, Coles LD, et al. Underdosing of Benzodiazepines in Patients With Status Epilepticus Enrolled in Established Status Epilepticus Treatment Trial. Acad Emerg Med. 2019;26(8):940-943. doi:10.1111/acem.13811
Summarized by Jorge Chalit, OMSII | Edited by Meg Joyce & Jorge Chalit
 

Contributor: Travis Barlock MD
Educational Pearls:
Ketamine is an NMDA receptor antagonist with a wide variety of uses in the emergency department. To dose ketamine remember the numbers 0.3, 1, and 3.
Pain dose
For acute pain relief administer 0.3 mg/kg of ketamine IV over 10-20 minutes (max of 30 mg).
Note: There is evidence that a lower dose of 0.1-0.15 mg/kg can be just as effective.
Dissociative dose
To use ketamine as an induction agent for intubation or for procedural sedation administer 1 mg/kg IV over 1-2 minutes.
IM for acute agitation
If a patient is out of control and a danger to themselves or others, administer 3 mg/kg intramuscularly (max 500 mg).
If you are giving IM ketamine it has to be in the concentrated 100 mg/ml vial.
Additional pearls
Pushing ketamine too quickly can cause laryngospasm.
Between .3 and 1 mg/kg is known as the recreational dose. You want to avoid this range because this is where ketamine starts to pick up its dissociative effects and can cause unpleasant and intense hallucinations. This is colloquially known as being in the “k-hole”.
References
Gao, M., Rejaei, D., & Liu, H. (2016). Ketamine use in current clinical practice. Acta pharmacologica Sinica, 37(7), 865–872. https://doi.org/10.1038/aps.2016.5
Lin, J., Figuerado, Y., Montgomery, A., Lee, J., Cannis, M., Norton, V. C., Calvo, R., & Sikand, H. (2021). Efficacy of ketamine for initial control of acute agitation in the emergency department: A randomized study. The American journal of emergency medicine, 44, 306–311. https://doi.org/10.1016/j.ajem.2020.04.013
Stirling, J., & McCoy, L. (2010). Quantifying the psychological effects of ketamine: from euphoria to the k-Hole. Substance use & misuse, 45(14), 2428–2443. https://doi.org/10.3109/10826081003793912
Summarized by Jeffrey Olson MS2 | Edited by Jorge Chalit, OMS II

Contributor: Travis Barlock MD
Educational Pearls:
Thrombolytic therapy (tPA or TNK) is often used in the ED for strokes
Use of anticoagulants with INR > 1.7 or  PT >15
Warfarin will reliably increase the INR
Current use of Direct thrombin inhibitor or Factor Xa inhibitor 
aPTT/PT/INR are insufficient to assess the degree of anticoagulant effect of Factor Xa inhibitors like apixaban (Eliquis) and rivaroxaban (Xarelto) 
Intracranial or intraspinal surgery in the last 3 months
Intracranial neoplasms or arteriovenous malformations also increase the risk of bleeding
Current intracranial or subarachnoid hemorrhage
History of intracranial hemorrhage from thrombolytic therapy also contraindicates tPA/TNK
Recent (within 21 days) or active gastrointestinal bleed
Hypertension
BP >185 systolic or >110 diastolic
Administer labetalol before thrombolytics to lower blood pressure
Timing of symptoms
Onset > 4.5 hours contraindicates tPA
Platelet count BGL Potential alternative explanation for stroke-like symptoms obviating need for thrombolytics
References
1. Fugate JE, Rabinstein AA. Absolute and Relative Contraindications to IV rt-PA for Acute Ischemic Stroke. The Neurohospitalist. 2015;5(3):110-121. doi:10.1177/1941874415578532
2. Powers WJ, Rabinstein AA, Ackerson T, et al. Guidelines for the Early Management of Patients with Acute Ischemic Stroke: 2019 Update to the 2018 Guidelines for the Early Management of Acute Ischemic Stroke a Guideline for Healthcare Professionals from the American Heart Association/American Stroke Association. Vol 50.; 2019. doi:10.1161/STR.0000000000000211
Summarized by Jorge Chalit, OMSII | Edited by Jorge Chalit