Podcast # 340: Drowning

Author: Chris Holmes, MD

Educational Pearls:

  • Epidemiology: 80% male, ages 1-4 at greatest risk, African-American > Caucasian.
  • Freshwater and ocean water may have more bacteria than pool water.
  • Salt water is hyperosmolar, which theoretically increases risk of pulmonary edema.
  • Greatest physiologic insult is from hypoxia secondary to fluid aspiration or laryngeal spasm. Patient survival is related to presentation on arrival.
  • Workup includes CXR and ABG; consider C-spine immobilization/imaging when cervical injury is strongly suspected (i.e. diving injury).
  • Treatment consists of supplemental oxygen therapy. Consider CPAP or intubation.

References

Szpilman D, Bierens JJ, Handley AJ, Orlowski JP. Drowning. N Engl J Med. 2012. 366(22):2102-10. doi: 10.1056/NEJMra1013317.

Schmidt A, Sempsrott J. Drowning In The Adult Population: Emergency Department Resuscitation And Treatment. Emerg Med Pract. 2015. 17(5):1-18.

Podcast #332: Door To Furosemide Time

Author: Nick Hatch, MD

Educational Pearls:

  • Recent study argues that CHF patients receiving furosemide within 60 minutes of arrival had a lower in-hospital mortality than those receiving it after (2.3% vs. 6.0%, p=0.002).
  • A flaw in the study is that there were significant baseline differences between groups.

References:

Matsue Y et al. Time-to-Furosemide Treatment and Mortality in Patients Hospitalized With Acute Heart Failure. JACC 2017. PMID: 28641794

Podcast #320: PE in Pregnancy

Author: Don Stader, M.D.

Educational Pearls:

  • Pulmonary embolism is one of the leading causes of maternal mortality.
  • There is disagreement among different medical societies about the value of D-dimer as a screening modality. If you use it, consider the rational D-dimer approach whereby you add 250 to your cut-off for every trimester.
  • A useful screening modality is an ultrasound of bilateral lower extremities looking for DVT.
  • Keep in mind, both a V/Q scan and CT scan have a significant amount of radiation. CTA is probably the right diagnostic test (less radiation than CT w&w/o).
  • Always use the shared decision-making model and clinical acumen to choose your tests.

References:

Leung AN, et. al. (2011). An official American Thoracic Society/Society of Thoracic Radiology clinical practice guideline: evaluation of suspected pulmonary embolism in pregnancy. American Journal of Respiratory and Critical Care Medicine. 184(10):1200-8

 

Polak JF, Wilkinson DL. (1991). Ultrasonographic diagnosis of symptomatic deep venous thrombosis in pregnancy. American Journal of Obstetrics and Gynecology. 165(3):625-9.

Sachs BP, et. al. (1987). Maternal mortality in Massachusetts. Trends and prevention. New England Journal of Medicine. 316(11):667-72.

Check out this episode!

Podcast #319: Cardiac Arrest Survival Factors

Author: Aaron Lessen, MD

Educational Pearls:

  • Shockable rhythms like V-fib or V-tach have a better prognosis than patients with PEA or asystole.
  • Recent study has shown an initial electrical frequency in PEA between 10-24/min had worse outcomes than PEA with initial rhythm over 60/min.
  • Patients with an initial electrical frequency in PEA over 60/min did just as well as patients with shockable rhythms. Of them, there was a 22% survival rate with 15% having a good neurologic outcome.

References:

Weiser, C., et al. (2018). Initial electrical frequency predicts survival and neurological outcome in out of hospital cardiac arrest patients with pulseless electrical activity. Resuscitation. 125:34-38

Podcast #308: Ultrasound in Cardiac Arrest

Author: Aaron Lessen, M.D.

Educational Pearls:

  • There is currently debate within the medical community about what constitutes cardiac activity on ultrasound in the setting of cardiac arrest. A recent study has shown there providers looking at the same clips from an echo will disagree about what constitutes cardiac activity.
  • Some of the confusion stems from movement that is not cardiac in etiology. For example, some alvular movement can be due to IV fluids and some cardiac motion can be due to the patient being bagged.
  • Cardiac activity is defined as “Any intrinsic motion of the myocardium.” However, even if this is present, it is important to ask if it clinically significant cardiac activity.
  • Despite disagreement, ultrasound can be useful for clinical decision making.

References:

Gaspari R et al. (2016) Emergency Department Point-Of-Care Ultrasound in Out-Of-Hospital  and in-ED Cardiac Arrest. Resuscitation; 109: 33 ? 39.

Hu K et al. (2017) Variability in Interpretation of Cardiac Standstill Among Physician Sonographers. Ann Emerg Med.

Podcast #303: Lazarus Effect

Author: Dylan Luyten, M.D.

Educational Pearls

  • The Lazarus phenomenon is the delayed return of spontaneous circulation after cessation of CPR.
  • A prospective study in Finland found 5 out of 840 patients where CPR was attempted in the setting of cardiac arrest experienced the Lazarus effect (about 0.6%).
  • 3 of these patients died on scene, and the other 2 died in the hospital at 1.5 and 26 hours respectively.
  • Ultimately, the Lazarus effect is rare, but it does occur and providers and family members should be aware that signs such as gasping or twitching may be seen after cardiac arrest, but the prognosis is still dismal.

References

Kuisma, M, et al. (September 2017) “Delayed return of spontaneous circulation (the Lazarus phenomenon) after cessation of out-of-hospital cardiopulmonary resuscitation”. Resuscitation. 118: 107-111

Podcast #291: Cincinnati Stroke Scale

Author: Nick Hatch, M.D.

Educational Pearls

  • The Cincinnati Stroke Scale uses 3 measures to screen for ischemic stroke. The measures are: facial asymmetry, speech quality and arm drift.
  • This scale is used commonly in EMS systems as a screening tool.
  • Studies show that having one out of the 3 elements correlates with a 72% chance of having an ischemic stroke, while having all 3 of the elements correlates with an 85% chance. Overall the scale is highly sensitive but not very specific  (92% and 48%, respectively, in one study).
  • The measures focus on anterior circulation function, and often misses posterior circulation strokes.
  • The Cincinnati Stroke Scale is good for EMS, but not necessarily for emergency physicians.

References:  http://onlinelibrary.wiley.com/store/10.1002/9781118783467.app5/asset/app5.pdf?v=1&t=jcf2yn71&s=3c2341ba472c1fcc88003dc0af7eac28691dd980

Podcast #282: EKG Changes in DKA

Author: Dave Rosenberg, M.D.

Educational Pearls

  • EKG changes that can be seen in DKA include ST elevation and peaked T-waves secondary to derangements in K levels.
  • In DKA,  serum K is high, but total body K is low, which can cause said EKG abnormalities.
  • Many things cause ST elevation besides MI, so think beyond STEMI.
  • When someone in in DKA, think about the “Three I’s” for underlying cause: (not taking) insulin, ischemia, infection.

References:  Nageswara Rao Chava. ECG in Diabetic Ketoacidosis. Arch Intern Med. 1984;144(12):2379?2380. doi:10.1001/archinte.1984.00350220101022

 

Podcast #280: Isolated Aphasia in Stroke

Author: Aaron Lessen, M.D.

Educational Pearls

  • Patients with an ischemic stroke from occlusion of the left middle cerebral artery often present with aphasia in addition to other neurological deficits.
  • A recent study looked at patients presenting with suspected stroke. Of the 700 patients recruited, 3% had isolated aphasia on exam.  On follow-up, none of the 3% had evidence of stroke on imaging. Underlying causes of the isolated aphasia in these patients included syncope, infections, seizures were the underlying cause.  

References: Gabriel Casella, Rafael H. Llinas, Elisabeth B. Marsh, Isolated aphasia in the emergency department: The likelihood of ischemia is low, Clinical Neurology and Neurosurgery, Volume 163, 2017, Pages 24-26, ISSN 0303-8467, https://doi.org/10.1016/j.clineuro.2017.10.013.

Podcast #268: Poiseuille’s Law

Author:  Dave Rosenberg, M.D.

Educational Pearls

  • Poiseuille’s Law addresses the flow of a fluid through a tube.
  • Many common ED presentations involve alterations in flow: asthma, MI, ischemic stroke, etc.
  • According to the law, flow increases with the 4th power of the radius. That is to say, doubling the radius of the tube will increase the flow by 16x.
  • Therefore, in situations that require re-opening of an anatomic tube (artery, airway), small changes in the size of the opening will result in dramatic effects.

References: https://www.openanesthesia.org/poiseuilles_law_iv_fluids/