Emergency Medical Minute – Détails, épisodes et analyse

Contributor: Aaron Lessen, MD

Educational Pearls:

How does an automated blood pressure cuff work?

• Automated blood pressure cuffs work differently than taking a manual blood pressure.

• While taking a manual blood pressure, one typically listens for Korotkoff sounds (turbulent flow) while slowly deflating the cuff.

• An automatic blood pressure cuff only senses the pressure in the cuff itself and specifically pays attention to oscillations in the pressure caused by when the pressure of the cuff is between the systolic (heart squeezing) and diastolic (heart relaxed) pressures.

• These oscillations are at a maximum when the pressure in the cuff matches the mean arterial pressure (MAP) and therefore the machines are most accurate at reporting the MAP.

• The machines then use the MAP and other information about the oscillations to estimate the systolic and diastolic pressures, which are less accurate.

What should you do if you need more accurate systolic and diastolic blood pressures?

• Take a manual blood pressure.

• Get an arterial-line (a-line), which provides continuous data for the blood pressure at the end of a catheter.

What happens if the cuff is too big or too small for the patient?

• If the cuff is too small it will overestimate the pressure.

• If the cuff is too large it will underestimate the pressure.

What should you do if the cuff cycles a bunch of times before reporting a blood pressure?

• It probably isn't very accurate so consider another method.

Bonus fact!

• The MAP is not directly in the middle of the systolic and diastolic pressures but is weighted towards the diastolic pressure. The MAP can be calculated by adding two-thirds of the diastolic pressure to one third of the systolic pressure. For example if the BP is 120/90 the MAP is 100 mmHg.

References

1. Benmira, A., Perez-Martin, A., Schuster, I., Aichoun, I., Coudray, S., Bereksi-Reguig, F., & Dauzat, M. (2016). From Korotkoff and Marey to automatic non-invasive oscillometric blood pressure measurement: does easiness come with reliability?. Expert review of medical devices, 13(2), 179–189. https://doi.org/10.1586/17434440.2016.1128821

2. Liu, J., Li, Y., Li, J., Zheng, D., & Liu, C. (2022). Sources of automatic office blood pressure measurement error: a systematic review. Physiological measurement, 43(9), 10.1088/1361-6579/ac890e. https://doi.org/10.1088/1361-6579/ac890e

3. Vilaplana J. M. (2006). Blood pressure measurement. Journal of renal care, 32(4), 210–213. https://doi.org/10.1111/j.1755-6686.2006.tb00025.x

Summarized by Jeffrey Olson, MS3 | Edited by Meg Joyce, MS1 & Jorge Chalit, OMS3

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Contributor: Megan Hurley, MD

Educational Pearls: 

• Heat cramps

• Occur due to electrolyte disturbances

• Most common electrolyte abnormalities are hyponatremia and hypokalemia

• Heat edema

• Caused by vasodilation with pooling of interstitial fluid in the extremities

• Heat rash (miliaria)

• Common in newborns and elderly

• Due to accumulation of sweat beneath eccrine ducts

• Heat syncope

• Lightheadedness, hypotension, and/or syncope in patients with peripheral vasodilation due to heat exposure

• Treatment is removal from the heat source and rehydration (IV fluids or Gatorade)

• Heat exhaustion

• Patients have elevated body temperature (greater than 38º C but less than 40º C)

• Symptoms include nausea, tachycardia, headache, sweating, and others

• Normal mental status or mild confusion that improves with cooling

• Treatment is removal from the heat source and hydration

• Classic heat stroke

• From prolonged exposure to heat

• Defined as a core body temperature > 40.5º C, though not required for diagnosis or treatment

• Presentation is similar to heat exhaustion with the addition of neurological deficits including ataxia

• Patients present "dry"

• Exertional heat stroke

• Prolonged exposure to heat during exercise

• Similar to classic heat stroke but the patients present "wet" due to antecedent treatment in ice baths or other field treatments

• Management of heat-related illnesses includes:

• Cooling

• Rehydration

• Evaluation of electrolytes

• Antipyretics are not helpful because heat-induced illnesses are not due to hypothalamic dysregulation

References

1. Casa DJ, McDermott BP, Lee EC, et al. Cold water immersion: the gold standard for exertional heatstroke treatment. Exerc Sport Sci Rev 2007; 35:141.

2. Ebi KL, Capon A, Berry P, et al. Hot weather and heat extremes: health risks. Lancet 2021; 398:698.

3. Epstein Y, Yanovich R. Heatstroke. N Engl J Med 2019; 380:2449.

4. Gardner JW, JA K. Clinical diagnosis, management, and surveillance of exertional heat illness. In: Textbook of Military Medicine, Zajitchuk R (Ed), Army Medical Center Borden Institute, Washington, DC 2001.

5. Khosla R, Guntupalli KK. Heat-related illnesses. Crit Care Clin 1999; 15:251.

6. Lipman GS, Gaudio FG, Eifling KP, et al. Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Heat Illness: 2019 Update. Wilderness Environ Med 2019; 30:S33.

Summarized by Jorge Chalit, OMSIII | Edited by Meg Joyce, MS1

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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:

1. 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

2. Kolecki P. Sympathomimetic Toxicity From Emergency Medicine. Medscape. Updated March 11, 2024. https://emedicine.medscape.com/article/818583-overview

3. 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

Contributor: Aaron Lessen, MD

Educational Pearls:

• Recent study evaluated if early exposure to an allergen impacted the rate of allergy development later in childhood
• Children were exposed to peanut, milk, wheat, and egg allergens at 3 months of age and then followed for 3 years
• 2.5-3% of children who were not exposed developed allergies to these allergens
• 1% of children exposed to the allergens developed allergies to these allerrgens
• Exposing 63 children to allergens at 3 months would prevent the development of food allergy in one child with no significant adverse events
• Future recommendations will likely be to gradually introduce allergens to children starting around 3 months

References

Skjerven HO, Lie A, Vettukattil R, et al. Early food intervention and skin emollients to prevent food allergy in young children (PreventADALL): a factorial, multicentre, cluster-randomised trial. Lancet. Jun 25 2022;399(10344):2398-2411. doi:10.1016/s0140-6736(22)00687-0

Summarized by Mark O'Brien, MS4 | Edited by John Spartz, MD, & Erik Verzemnieks, MD

In an effort to promote diversity, equity, and inclusion in Emergency Medicine, The Emergency Medical Minute is proud to present our 2nd annual Diversity and Inclusion Award. We support increasing the representation of underrepresented groups in medicine and extend this award to individuals applying to emergency medicine residencies during the 2022-2023 cycle. For information on award eligibility and the application process, visit https://emergencymedicalminute.com/edi-award/

Donate to EMM today!

Contributor: Travis Barlock, MD

Educational Pearls:

• The presence of a STEMI has traditionally been used to determine if a patient with acute chest pain requires urgent cath lab management
• STEMI indicates an occluded coronary artery, and urgent intervention is needed to restore perfusion to ischemic tissue
• Patients with occluded coronary arteries can present with EKG findings other than STEMI
• 2022 ACC Expert Consensus Decision Pathway on the Evaluation and Disposition of Acute Chest Pain in the Emergency Department was recently published in the Journal of the American College of Cardiology

• Recognizes STEMI equivalents that necessitate cath lab management
• ST depression in precordial leads
• Indicates a posterior infarct/possible RCA occlusion
• LBBB c ST elevation meeting modified Sgarbossa criteria
• Hyperacute and/or De Winter T wave
• First indication of coronary artery occlusion
• Most beneficial time to initiate cath lab because more tissue is salvageable
• These recommendations will likely alter clinical practice for ED management of acute chest pain

References

Kontos MC, de Lemos JA, Deitelzweig SB, et al. 2022 ACC Expert Consensus Decision Pathway on the Evaluation and Disposition of Acute Chest Pain in the Emergency Department: A Report of the American College of Cardiology Solution Set Oversight Committee. J Am Coll Cardiol. Oct 6 2022;doi:10.1016/j.jacc.2022.08.750

Meyers HP, Bracey A, Lee D, et al. Comparison of the ST-Elevation Myocardial Infarction (STEMI) vs. NSTEMI and Occlusion MI (OMI) vs. NOMI Paradigms of Acute MI. J Emerg Med. Mar 2021;60(3):273-284. doi:10.1016/j.jemermed.2020.10.026

 Tziakas D, Chalikias G, Al-Lamee R, Kaski JC. Total coronary occlusion in non ST elevation myocardial infarction: Time to change our practice? Int J Cardiol. Apr 15 2021;329:1-8. doi:10.1016/j.ijcard.2020.12.082

Summarized by Mark O'Brien, MS4 | Edited by John Spartz, MD, & Erik Verzemnieks, MD

In an effort to promote diversity, equity, and inclusion in Emergency Medicine, The Emergency Medical Minute is proud to present our 2nd annual Diversity and Inclusion Award. We support increasing the representation of underrepresented groups in medicine and extend this award to individuals applying to emergency medicine residencies during the 2022-2023 cycle. For information on award eligibility and the application process, visit https://emergencymedicalminute.com/edi-award/

Donate to EMM today!

Contributor: Aaron Lessen, MD

Educational Pearls:

• In urban settings, it is becoming more common for police to transport critical patients from scene to hospital
• A 2022 multicenter observational study compared mortality rates in patients with penetrating injury to torso and/or proximal extremity when transported by EMS versus police
• Approximately 18% of patients were transported by police 
• Overall mortality was approximately 15% in both groups 
• In patients with more severe injury, mortality was still similar at approximately 36% and 38% respectively 

References

Taghavi S, Maher Z, Goldberg AJ, et al. An analysis of police transport in an Eastern Association for the Surgery of Trauma multicenter trial examining prehospital procedures in penetrating trauma patients. J Trauma Acute Care Surg. 2022;93(2):265-272. doi:10.1097/TA.0000000000003563

Jacoby SF, Branas CC, Holena DN, Kaufman EJ. Beyond survival: the broader consequences of prehospital transport by police for penetrating trauma. Trauma Surg Acute Care Open. 2020;5(1):e000541. Published 2020 Nov 26. doi:10.1136/tsaco-2020-000541

Summarized by Kirsten Hughes, MS4 | Edited by John Spartz, MS4 & Erik Verzemnieks, MD

In an effort to promote diversity, equity, and inclusion in Emergency Medicine, The Emergency Medical Minute is proud to present our 2nd annual Diversity and Inclusion Award. We support increasing the representation of underrepresented groups in medicine and extend this award to individuals applying to emergency medicine residencies during the 2022-2023 cycle. For information on award eligibility and the application process, visit https://emergencymedicalminute.com/edi-award/

Donate to EMM today!

Contributor: Travis Barlock, MD

Educational Pearls:

• Catheter related blood infections were thought to be caused by skin flora seeding the catheter. Thus, significant effort is applied to sterility and skin preparation.  
• However, studies have shown that bacteria growing on the tip of the catheter is not consistent with growth on cultures of skin.  
• Staphylococcus epidermidis is commonly found on cultures of catheter sites. It has also been found in the gut flora of >50% of ICU patients. Rates of catheter related blood infections have been decreased through oral decontamination and early feeding. 
• These findings suggest enteral bacterial translation as a major source of blood stream infection.

References

O'Grady NP, Alexander M, Burns LA, et al. Guidelines for the prevention of intravascular catheter-related infections. Clin Infect Dis. 2011;52(9):e162-e193. doi:10.1093/cid/cir257

von Eiff C, Becker K, Machka K, Stammer H, Peters G. Nasal carriage as a source of Staphylococcus aureus bacteremia. Study Group. N Engl J Med. 2001;344(1):11-16. doi:10.1056/NEJM200101043440102

ALTEMEIER WA, HUMMEL RP, HILL EO. Staphylococcal enterocolitis following antibiotic therapy. Ann Surg. 1963;157(6):847-858. doi:10.1097/00000658-196306000-00003

Marshall JC, Christou NV, Horn R, Meakins JL. The microbiology of multiple organ failure. The proximal gastrointestinal tract as an occult reservoir of pathogens. Arch Surg. 1988;123(3):309-315. doi:10.1001/archsurg.1988.01400270043006

Mrozek N, Lautrette A, Aumeran C, et al. Bloodstream infection after positive catheter cultures: what are the risks in the intensive care unit when catheters are routinely cultured on removal?. Crit Care Med. 2011;39(6):1301-1305. doi:10.1097/CCM.0b013e3182120190

Atela I, Coll P, Rello J, et al. Serial surveillance cultures of skin and catheter hub specimens from critically ill patients with central venous catheters: molecular epidemiology of infection and implications for clinical management and research. J Clin Microbiol. 1997;35(7):1784-1790. doi:10.1128/jcm.35.7.1784-1790.1997

Tani T, Hanasawa K, Endo Y, et al. Bacterial translocation as a cause of septic shock in humans: a report of two cases. Surg Today. 1997;27(5):447-449. doi:10.1007/BF02385710

Summarized by Kirsten Hughes, MS4 | Edited by John Spartz, MS4 & Erik Verzemnieks, MD

In an effort to promote diversity, equity, and inclusion in Emergency Medicine, The Emergency Medical Minute is proud to present our 2nd annual Diversity and Inclusion Award. We support increasing the representation of underrepresented groups in medicine and extend this award to individuals applying to emergency medicine residencies during the 2022-2023 cycle. For information on award eligibility and the application process, visit https://emergencymedicalminute.com/edi-award/

Donate to EMM today!

Contributor: Jared Scott, MD

Educational Pearls:

• Immediate resuscitative thoracotomy can be performed in the ED to gain rapid access to the thoracic cavity in cases of traumatic cardiac arrest
• Western Trauma Association Society Criteria for ED thoracotomy
• • Blunt trauma + <10 min of prehospital CPR
  • Penetrating trauma to torso + <15 min prehospital CPR
  • Penetrating trauma to the neck/extremity + <5 min prehospital CPR
  • Signs of life with refractory shock can consider resuscitative thoracotomy
• Outcomes in immediate resuscitative thoracotomy are poor but are improving
• A recent study evaluated over 2,000 patients meeting inclusion criteria for immediate resuscitative thoracotomy
• •  Overall survival rate of 20%
  • • 26% survival rate in penetrating trauma
    •  7% survival rate in blunt trauma
  • Predictors for poor outcomes
  • • Patient age > 60 years
    • Blunt trauma mechanism of injury
    • A prehospital or ED HR <60 bpm
    • Absent signs of life at time of ED arrival
• When criteria are met, immediate resuscitative thoracotomy should rapidly be performed in the ED

References

Burlew CC, Moore EE, Moore FA, et al. Western Trauma Association critical decisions in trauma: resuscitative thoracotomy. J Trauma Acute Care Surg. 2012;73(6):1359-1363.

Panossian VS, Nederpelt CJ, El Hechi MW, et al. Emergency Resuscitative Thoracotomy: A Nationwide Analysis of Outcomes and Predictors of Futility. J Surg Res. 2020;255:486-494.

Summarized by Mark O'Brien, MS4 | Edited by John Spartz, MS4 & Erik Verzemnieks, MD

In an effort to promote diversity, equity, and inclusion in Emergency Medicine, The Emergency Medical Minute is proud to present our 2nd annual Diversity and Inclusion Award. We support increasing the representation of underrepresented groups in medicine and extend this award to individuals applying to emergency medicine residencies during the 2022-2023 cycle. For information on award eligibility and the application process, visit https://emergencymedicalminute.com/edi-award/

Donate to EMM today!

Contributor: Aaron Lessen, MD

Educational Pearls:

• Lateral Cutaneous Femoral Nerve Entrapment Syndrome, also known as Meralgia Paresthetica, results from entrapment of the lateral cutaneous femoral nerve, often as it exits the pelvis under the inguinal ligament. 
• Meralgia Paresthetica is associated with obesity, pregnancy, compression from clothing or belts and diabetes.
• Symptoms include numbness, paresthesia and pain of the proximal lateral thigh. Signs or symptoms of radiculopathy such as weakness, loss of reflexes or severe back pain should not be present.
• Diagnosis is clinical and does not require further imaging if there are no additional or concerning findings. 
• Meralgia Paresthetica typically resolves over time without intervention; however patients should be counseled on weight loss, diabetes control and avoidance of compressive clothing as relieving factors.   

References

Solomons JNT, Sagir A, Yazdi C. Meralgia Paresthetica. Curr Pain Headache Rep. 2022;26(7):525-531. doi:10.1007/s11916-022-01053-7

Grossman MG, Ducey SA, Nadler SS, Levy AS. Meralgia paresthetica: diagnosis and treatment. J Am Acad Orthop Surg. 2001;9(5):336-344. doi:10.5435/00124635-200109000-00007

Image from my.clevelandclinic.org

Summarized by Kirsten Hughes, MS4 | Edited by John Spartz, MD & Erik Verzemnieks, MD

In an effort to promote diversity, equity, and inclusion in Emergency Medicine, The Emergency Medical Minute is proud to present our 2nd annual Diversity and Inclusion Award. We support increasing the representation of underrepresented groups in medicine and extend this award to individuals applying to emergency medicine residencies during the 2022-2023 cycle. For information on award eligibility and the application process, visit https://emergencymedicalminute.com/edi-award/

Donate to EMM today!

Contributor: Travis Barlock, MD

Educational Pearls:

• An EKG should be obtained quickly after a syncopal event to identify possible life-threatening causes such as ischemia and arrhythmia
• WOBBLER is a good mnemonic for remembering additional EKG findings to look for in syncope
•  Wolff-Parkinson-White (WPW)
• Check for delta wave on QRS
• Obstructed AV node
• Any potential heart blocks
• Brugada syndrome
• Na channel blockade that can cause ST elevations in anterior leads
• Bifascicular block
• Conduction blockade in two of the three fascicles increases risk of complete heart block
• Left Ventricular Hypertrophy (LVH)
• Can be a sign of HOCM (younger patients) or aortic stenosis (older patients)
• Epsilon waves
• Positive deflections after the QRS that is seen in arrhythmogenic right ventricular dysplasia
• Repolarization abnormalities
• Prolonged/shortened QT segments

References

Martow E, Sandhu R. When Is Syncope Arrhythmic? Med Clin North Am. 2019;103(5):793-807.

Solbiati M, Dipaola F, Villa P, et al. Predictive Accuracy of Electrocardiographic Monitoring of Patients With Syncope in the Emergency Department: The SyMoNE Multicenter Study. Acad Emerg Med. 2020;27(1):15-23.

Summarized by Mark O'Brien, MS4 | Edited by John Spartz, MD & Erik Verzemnieks, MD

In an effort to promote diversity, equity, and inclusion in Emergency Medicine, The Emergency Medical Minute is proud to present our 2nd annual Diversity and Inclusion Award. We support increasing the representation of underrepresented groups in medicine and extend this award to individuals applying to emergency medicine residencies during the 2022-2023 cycle. For information on award eligibility and the application process, visit https://emergencymedicalminute.com/edi-award/