Emergency Medical Minute Emergency Medical Minute

Contributor: Travis Barlock MD
Educational Pearls:
Recent study assessed outcomes after ROSC with epinephrine vs. norepinephrine
Observational multicenter study from 2011-2018
285 patients received epineprhine and 481 received norepinephrine
Epinephrine was associated with an increase in all-cause mortality (primary outcome)
Odds ratio 2.6; 95%CI 1.4-4.7; P = 0.002
Higher cardiovascular mortality (secondary outcome)
Higher proportion of unfavorable neurological outcome (secondary outcome)
Norepinephrine is the vasopressor of choice in post-cardiac arrest care
References
Bougouin W, Slimani K, Renaudier M, et al. Epinephrine versus norepinephrine in cardiac arrest patients with post-resuscitation shock. Intensive Care Med. 2022;48(3):300-310. doi:10.1007/s00134-021-06608-7
Summarized by Jorge Chalit, OMSIII | Edited by Meg Joyce & Jorge Chalit
 

Contributor: Taylor Lynch, MD
Educational Pearls:
Opioid Epidemic- quick facts
Drug overdoses, primarily driven by opioids, have become the leading cause of accidental death in the U.S. for individuals aged 18-45.
In 2021, opioids were involved in nearly 75% of all drug overdose deaths
The rise of synthetic opioids like fentanyl, which is much more potent than heroin or prescription opioids, has played a major role in the increase in overdose deaths
What is Narcan AKA Naloxone?
Competitive opioid antagonist. It sits on the receptor but doesn’t activate it.
When do we give Narcan?
Respiratory rate less than 8-10 breaths per minute
Should you check the pupils?
An opioid overdose classically presents with pinpoint pupils BUT…
Hypercapnia from bradypnea can normalize the pupils
Taking other drugs at the same time like cocaine or meth can counteract the pupillary effects
Basilar stroke could also cause small pupils, so don’t anchor on an opioid overdose
How does Narcan affect the body?
Relatively safe even if the patient is not experiencing an opioid overdose. So when in doubt, give the Narcan.
What if the patient is opioid naive and overdosing?
Use a large dose given that this patient is unlikely to withdraw
0.4-2 mg every 3-5 minutes
What if the patient is a chronic opioid user
Use a smaller dose such as 0.04-0.4 mg to avoid precipitated withdrawal
How fast does Narcan work?
Given intravenously (IV), onset is 1-2 min
Given intranasal (IN), onset is 3-4 min
Given intramuscularly (IM), onset is ~6 min
Duration of action is 60 mins, with a range of 20-90 minutes
How does that compare to the duration of action of common opioids?
Heroine lasts 60 min
Fentanyl lasts 30-60 min, depending on route
Carfentanyl lasts ~5 hrs
Methadone lasts 12-24 hrs
So we really need to be conscious about redosing
How do you monitor someone treated with Narcan?
Pay close attention to the end-tidal CO2 to ensure that are ventilating appropriately
Be cautious with giving O2 as it might mask hypoventilation
Watch the respiratory rate
Give Narcan as needed
Observe for at least 2-4 hours after the last Narcan dose
Larger the dose, longer the observation period
Who gets a drip?
If they have gotten ~3 doses, time to start the drip
Start at 2/3rds last effective wake-up dose
Complications
Flash pulm edema
0.2-3.6% complication rate
Might be from the catecholamine surge from abrupt wake-up
Might also be from large inspiratory effort against a partially closed glottis which creates too much negative pressure
Treat with BIPAP if awake and intubation if not awake
Should you give Narcan in cardiac arrest?
Short answer no. During ACLS you take over breathing for the patient and that is pretty much the only way that Narcan can help
Just focus on high quality CPR
References
https://nida.nih.gov/research-topics/trends-statistics/overdose-death-rates#:~:text=Drug%20overdose%20deaths%20involving%20prescription,of%20deaths%20declined%20to%2014%2C716.
Elkattawy, S., Alyacoub, R., Ejikeme, C., Noori, M. A. M., & Remolina, C. (2021). Naloxone induced pulmonary edema. Journal of community hospital internal medicine perspectives, 11(1), 139–142. https://doi.org/10.1080/20009666.2020.1854417
van Lemmen, M., Florian, J., Li, Z., van Velzen, M., van Dorp, E., Niesters, M., Sarton, E., Olofsen, E., van der Schrier, R., Strauss, D. G., & Dahan, A. (2023). Opioid Overdose: Limitations in Naloxone Reversal of Respiratory Depression and Prevention of Cardiac Arrest. Anesthesiology, 139(3), 342–353. https://doi.org/10.1097/ALN.0000000000004622
Yousefifard, M., Vazirizadeh-Mahabadi, M. H., Neishaboori, A. M., Alavi, S. N. R., Amiri, M., Baratloo, A., & Saberian, P. (2019). Intranasal versus Intramuscular/Intravenous Naloxone for Pre-hospital Opioid Overdose: A Systematic Review and Meta-analysis. Advanced jo

Contributor: Taylor Lynch MD
Educational Pearls:
Anticholinergics are found in many medications, including over-the-counter remedies
Medications include:
Diphenhydramine
Tricyclic antidepressants like amitriptyline
Atropine
Antipsychotics like olanzapine
Antispasmodics - dicyclomine
Jimsonweed
Muscaria mushrooms
Mechanism of action involves competitive antagonism of the muscarinic receptor
Symptomatic presentation is easily remembered via the mnemonic:
Dry as a bone - anhidrosis due to cholinergic antagonism at sweat glands
Red as a beet - cutaneous vasodilation leads to skin flushing
Hot as a hare - anhidrotic hyperthermia
Blind as a bat - pupillary dilation and ineffective accommodation
Mad as a hatter - anxiety, agitation, dysarthria, hallucinations, and others
Clinical management
ABCs
Benzodiazepines for supportive care, agitation, and seizures
Sodium bicarbonate for TCA toxicity due to widened QRS
Activated charcoal if patient present Temperature monitoring
Contact poison control with questions
Physostigmine controversy
Physostigmine is a reversible cholinesterase inhibitor that can cross the blood-brain barrier so in theory it would be a useful antidote BUT…
There is a black box warning for asystole and seizures when physostigmine is used this way
Therefore it is contraindicated in TCA overdoses
However, it is still indicated in certain anticholinergic overdoses with delirium
Disposition
Admission criteria include: symptoms >6 hours, CNS findings, QRS prolongation, hyperthermia, and rhabdomyolysis
ICU admission criteria include: delirium, dysrhythmias, seizures, coma, or requirement for physostigmine drip
References
1. Arens AM, Shah K, Al-Abri S, Olson KR, Kearney T. Safety and effectiveness of physostigmine: a 10-year retrospective review. Clin Toxicol (Phila). 2018;56(2):101-107. doi:10.1080/15563650.2017.1342828
2. Nguyen TT, Armengol C, Wilhoite G, Cumpston KL, Wills BK. Adverse events from physostigmine: An observational study. Am J Emerg Med. 2018;36(1):141-142. doi:10.1016/j.ajem.2017.07.006
3. Scharman E, Erdman A, Wax P, et al. Diphenhydramine and dimenhydrinate poisoning: An evidence-based consensus guideline for out-of-hospital management. Clin Toxicol. 2006;44(3):205-223. doi:10.1080/15563650600585920
4. Shervette RE 3rd, Schydlower M, Lampe RM, Fearnow RG. Jimson "loco" weed abuse in adolescents. Pediatrics. 1979;63(4):520-523.
5. Woolf AD, Erdman AR, Nelson LS, et al. Tricyclic antidepressant poisoning: An evidence-based consensus guideline for out-of-hospital management. Clin Toxicol. 2007;45(3):203-233. doi:10.1080/15563650701226192
Summarized by Jorge Chalit, OMSIII | Edited by Jorge Chalit
 

Contributor: Aaron Lessen, MD
Educational Pearls:
How fast does cellulitis recover?
A recent prospective cohort study took a look at this question.
The study included 300 adults with cellulitis (excluding those with peri-orbital cellulitis or abscesses) in two emergency departments in Queensland, Australia.
They collected data from initial and follow-up surveys at 3, 7, and 14 days, and compared clinician and patient assessments at day 14.
Improvement was fastest between day 0 and day 3, with gradual progress thereafter.
At day 14, many still had skin redness and swelling, though warmth had often resolved. Clinicians reported higher cure rates than patients (85.8% vs. 52.8%).
Conclusion:
Cellulitis symptoms improve quickly at first but continue to linger for many patients.
Patients and doctors often have different views on when cellulitis is fully cured.
How should we counsel patients?
Even on antibiotics, the margins of the cellulitis may continue to spread a small amount.
Skin warmth should be the first symptom to go away.
It takes time to get better. Only about 50% of patients believed their cellulitis was cured at 2 weeks.
References
Nightingale, R. S., Etheridge, N., Sweeny, A. L., Smyth, G., Dace, W., Pellatt, R. A. F., Snelling, P. J., Yadav, K., & Keijzers, G. (2024). Cellulitis in the Emergency Department: A prospective cohort study with patient-centred follow-up. Emergency medicine Australasia : EMA, 10.1111/1742-6723.14401. Advance online publication. https://doi.org/10.1111/1742-6723.14401
Summarized by Jeffrey Olson MS2 | Edited by Meg Joyce & Jorge Chalit, OMSIII

Contributor: Aaron Lessen MD
Educational Pearls:
A recent study assessed EMS treatment of high blood pressure in the field
2404 patients randomized to prehospital treatment (1205)  vs. usual care (1199)
Included patients with prehospital BP greater than 150 mm Hg
The treatment arm’s BP goal was 130-140 mm Hg
The primary efficacy outcome was functional status 90 days out
Stroke was confirmed by imaging upon hospital arrival
On arrival, the mean SBP of the treatment arm was 159 mm Hg compared with 170 mm Hg in the usual care group
No significant difference in functional outcomes between the treatment group and the usual care group (Common Odds Ratio of 1.00, 95% CI = 0.87-1.15)
Post-imaging analysis revealed 46.5% of the undifferentiated patients had a hemorrhagic stroke
Prehospital reduction in BP did reduce the odds of poor functional outcome in hemorrhagic stroke patients alone (Common Odds Ratio 0.75, 95% CI 0.60-0.92)
Those with ischemic stroke had increased odds of poor functional outcome (Common Odds Ratio 1.30, 95% CI 1.06-1.60)
Bottom line: it is challenging to identify the stroke type in the prehospital setting and therefore not necessarily helpful to treat the blood pressure
References
1. Ren X, Zhang C, Xu P, et al. Intensive Ambulance-Delivered Blood- Pressure Reduction in Hyperacute Stroke. New England Journal of Medicine. 2024;390(20):1862-1872. doi:10.1056/NEJMoa2314741
Summarized by Jorge Chalit, OMSIII | Edited by Meg Joyce & Jorge Chalit
 

Contributor: Taylor Lynch MD
Educational Pearls:
Overview: Sympathomimetic drugs mimic the fight or flight response, affecting monoamines such as dopamine, norepinephrine, and epinephrine Limited therapeutic use, often abused. Types: Amphetamines: Methamphetamine, Adderall, Ritalin, Vyvanse MDMA (Ecstasy) Cocaine (Both hydrochloride salt & free based crack cocaine) Theophylline (Asthma treatment) Ephedrine (For low blood pressure) BZP, Oxymetazoline (Afrin), Pseudoephedrine (Sudafed) MAO Inhibitors (treatment-resistant depression) Mechanisms: Act on adrenergic and dopaminergic receptors. Cocaine blocks dopamine and serotonin reuptake. Methamphetamines increase stimulatory neurotransmitter release MAO Inhibitors prevent neurotransmitter breakdown. Symptoms: Agitation, tachycardia, hypertension, hyperactive bowel sounds, diuresis, hyperthermia. Severe cases: Angina, seizures, cardiovascular collapse. Diagnosis: Clinical examination and history. Differentiate from anticholinergic toxidrome by diaphoresis and hyperactive bowel sounds. Tests: EKG, cardiac biomarkers, chest X-ray, blood gas, BMP, CK, coagulation studies, U-tox screen. Treatment: Stabilize ABCs, IV hydration, temperature monitoring, benzodiazepines. Avoid beta-blockers due to unopposed alpha agonism. Whole bowel irrigation for body packers; surgical removal if packets rupture. IV hydration for high CK levels. Observation period often necessary. Recap: Mimic sympathetic nervous system. Key symptoms: Diaphoresis, hyperactive bowel sounds. Treatment: Supportive care, benzodiazepines. Use poison control as a resource. References:
Costa VM, Grazziotin Rossato Grando L, Milandri E, Nardi J, Teixeira P, Mladěnka P, Remião F. Natural Sympathomimetic Drugs: From Pharmacology to Toxicology. Biomolecules. 2022;12(12):1793. doi:10.3390/biom12121793
Kolecki P. Sympathomimetic Toxicity From Emergency Medicine. Medscape. Updated March 11, 2024. https://emedicine.medscape.com/article/818583-overview
Williams RH, Erickson T, Broussard LA. Evaluating Sympathomimetic Intoxication in an Emergency Setting. Lab Med. 2000;31(9):497-508. https://doi.org/10.1309/WVX1-6FPV-E2LC-B6YG
Summarized by Steven Fujaros | Edited by Jorge Chalit, OMSIII