Emergency Medical Minute

Author: David Rosenberg, M.D. Educational Pearls Preoxygenation is done before rapid sequence intubation, and should be done even if SaO2 is at 100%. Preoxygenation is done to fill the lungs with oxygen rather than ambient air, which is only 20% O2. While the patient is paralyzed, the O2-filled lungs will continue to oxygenate venous blood, buying you more time for intubation. BiPAP is an effective tool for pre-oxygenation. References: https://lifeinthefastlane.com/ccc/preoxygenation/

Podcast #259: TIA Author: Peter Bakes, M.D. Educational Pearls A TIA is defined as focal neurological deficit that resolves within 24 hours and has negative imaging. The etiology is a transient thrombus, embolus, or narrowing of a branch of a cerebral artery. Screening tests are generally negative and low-yield. MRI and vascular imaging are usually done to look for reversible causes. Patients presenting with TIA are usually admitted because of a higher risk for stroke. However, there are some patients that are low-risk and do not require admission. Risk can be assessed using the "ABCD" mnemonic: Age>60, BP (history of HTN), Clinical presentation (area of deficit), Diabetes/Duration of symptoms. See reference link for scoring sheet. Patients with a low enough score may be eligible for outpatient follow-up. References: http://www.stroke.org/sites/default/files/resources/tia-abcd2-tool.pdf?docID

Author: Dylan Luyten, M.D. Educational Pearls Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA). Exsanguination is a major cause of mortality in trauma One temporizing technique to buy time to definitive hemorrhage control is to occlude the aorta thereby shunting blood away from pelvis and lower extremities, increasing cardiac afterload to increase myocardial and brain perfusion. Rather than perform a thoracotomy to cross clamp aorta, a REBOA catheter may be introduced into the aorta via the common femoral artery and a balloon inflated in the descending aorta to occlude it. The indications for REBOA include PEA arrest of brief duration attributable to exsanguination for sub-diaphragmatic source in a young, healthy patient, or severe hypovolemic shock or those in an agonal state due to non-compressible hemorrhage not responding to volume and in whom obstructive cause of shock has been ruled out. Contraindicated in prolonged arrest, suspected proximal aortic injury, advanced age/comorbidities. Controversies and evidence: High quality evidence is lacking - as it is for much of what we do and even consider standard of care in trauma. It has not been shown to improve survival, which is hard to demonstrate. Role in remote settings vs trauma centers unclear. Further refinements of indication for use are likely to occur with time and experience. Summarize - REBOA is a promising relatively new technology that may have potential to improve outcomes in the sickest of trauma patients. Reference: https://lifeinthefastlane.com/ccc/resuscitative-endovascular-balloon-occlusion-aorta-reboa/

Educational Pearls Strangulation is common in cases of domestic violence and sexual assault, and it is associated with higher mortality People who have been strangled have a higher rate of stroke due to vascular damage to carotid artery Only 50% of people who die from strangulation show external signs of trauma CTA should be done in all those who experience LOC or incontinence from strangulation 50-60sec of strangulation is all that is required to produce LOC References: http://epmonthly.com/article/clinical-focus-strangulation-and-hanging-injuries/

Authors: Don Stader, M.D & Rachael Duncan, PharmD BCPS BCCCP Educational Pearls Fentanyl patches may be abused in many ways, including changing the patches more frequently, chewing them, extracting the fentanyl in a tea, and administering them rectally. Fentanyl is very lipophilic and has a fast onset, but it has a very low bioavailability when given enterally, because it does not survive the stomach and 1st pass metabolism. It can be given IV, intranasal, through the buccal mucosa, or transdermal. When patients present with fentanyl overdose due to ingestion of a patch, it is more important to find out how long the patient had the patch in their mouth, since that is the principal form of absorption. References: http://www.medscape.org/viewarticle/518441_3

Author: Heidi Wald, MD, MSPH Associate Professor of Medicine - University of Colorado School of Medicine, Physician Advisor - Colorado Hospital Association Dr. Heidi Wald explains common misconceptions of UTI's in elderly patients and provides tips on how to properly identify them. References: Trestioreanu , Adi Lador , May-Tal Sauerbrun-Cutler and Leonard Leibovici Antibiotics for asymptomatic bacteriuria Cochrane Collaborative Online Publication Date: April 2015. Trautner BW, Bhimani RD, Amspoker AB, et al. Development and validation of an algorithm to recalibrate mental models and reduce diagnostic errors associated with catheter-associated bacteriuria. BMC Med Inform Decis Mak 2013;13:48. Trautner BW, Grigoryan L, Petersen NJ, et al. Effectiveness of an Antimicrobial Stewardship Approach for Urinary Catheter Associated Asymptomatic Bacteriuria. JAMA Intern Med 2015. D'Agata E, Loeb MB, and Mitchell. Challenges in assessing nursing home residents with advanced dementia for suspected urinary tract infections. J Am Geriatr Soc.2013 Jan;61(1):62-6. doi: 10.1111/jgs.12070. Stone ND, Ashraf MS, Calder J, et al. Surveillance definitions of infections in long-term care facilities: revisiting the McGeer criteria. Infect Control Hosp Epidemiol 2012;33:965-77.

Author: Erik Verzemnieks, M.D. Educational Pearls Posterior vitreous detachment is the tearing of the lining in the back of of the eye. Patients often present with loss of vision and floaters. Diagnosis can be made with US. This is a benign diagnosis, but 10-15% can progress to retinal detachment , so follow up with ophthalmology is recommended. References: http://www.medscape.com/viewarticle/513226

Author: Chris Holmes, M.D. Educational Pearls There's little/no data about the necessary length of an antibiotic course, nor has it proven that stopping a course of antibiotics early selects for the most resistant bugs. There's little incentive for drug companies to fund this type of study. Pro-calcitonin levels have been used in some settings to distinguish if an infection has resolved or not, but this may not be feasible in an outpatient setting. References: Llewelyn, Martin J et al. The antibiotic course has had its day. 2017. BMJ

Author: Nick Hatch, M.D. Educational Pearls Photic or solar retinitis occurs when you stare at the sun. The refractive power of the lens of the eye concentrates the light of the sun on the retina, stimulating the production of free radicals, damaging photoreceptors. Solar retinitis may present hours-days after light exposure. Patients will present with patchy loss of vision without pain, since the retina has no pain receptors. In one study during an eclipse in the UK, of those who initially presented with vision loss due to solar retinitis, 92% recovered full vision. References: Dobson R. UK hospitals assess eye damage after solar eclipse. BMJ : British Medical Journal. 1999;319(7208):469.

Author: Sam Killian, M.D. Educational Pearls The tongue blade test is done for mandible fractures, which make up 40-60% of facial fractures. The test is done by having the patient bite down on a tongue depressor on one side of the mouth. The provider then tries to snap the tongue depressor. This is repeated on the other side of the mouth. The test is positive if the patient complains of pain before the depressor can be broken on either side. It has been compared to CT and X-ray and has a similar sensitivity and specificity (95% and 65%, respectively). References: J. Neiner, et al. Tongue Blade Bite Test Predicts Mandible Fractures. Craniomaxillofac Trauma Reconstr. 2016