What is the correct antidote for a patient who is poisoned with the pictured substance?
- Digoxin Specific Fab
- Hydroxocobalamin/Sodium Thiosulfate
(photo used with permission courtesy of Maureen Dallhoff, MD)
Which toxic exposure can present with the pictured rash along with hypertension and tachycardia mimicking pheochromocytoma?
An acute aortic dissection (AAD) can be a life-threatening emergency which frequently requires rapid and precise control of the patient’s heart rate and blood pressure. The 2010 guidelines for management of patients with thoracic aortic disease suggest a heart rate goal of <60 bpm and a systolic blood pressure between 100-120 mmHg. In order to achieve this, a rapid-acting beta-blocker (i.e., esmolol) may be used in combination with an IV calcium channel blocker (i.e., nicardipine or clevidipine). These medications need to be monitored closely to avoid overshooting these goals and causing hemodynamic compromise. Ideally, an arterial line would be used to monitor the patient’s blood pressure, however this may not always be feasible so a traditional, noninvasive blood pressure cuff can be used. This may be complicated if the patient has the classic, but not universal, finding of unequal systolic blood pressure values between their left and right extremities. This raises the question, in a patient with an AAD and disparate blood pressures in each arm, which arm reading should be used for monitoring?
A 2018 study from Um et al. evaluated 111 patients with an AAD and compared them with 111 control patients. This study found that while a systolic blood pressure difference of >20 mmHg between sides was a positive predictor for an AAD, the presence of a pulse deficit had a higher diagnostic accuracy. For the purpose of this study, a pulse deficit was defined as “any recorded difference in volume/force or difference in obvious signs of malperfusion”. The cause of an unequal blood pressure or pulse deficit in the upper extremities in this population is typically due to dissection of the brachiocephalic or subclavian arteries. In order to properly achieve the desired blood pressure reduction in patients with divergent blood pressure values, the higher value should be used for titration of antihypertensives. This is due to the occurrence of pseudohypotension occurring in the limb with the dissected artery.
- Aggressive and precise heart rate and blood pressure control are critical for patients with an acute aortic dissection
- The presence of a pulse deficit may provide better diagnostic accuracy than a difference in systolic blood pressure
- When titrating blood pressure medications in patients with unequal blood pressure readings between extremities, the higher value should be utilized
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- Hiratzka LF, Bakris GL, Beckman JA, et al. 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with thoracic aortic disease Circulation. 2010;121(13):e266-369. doi: 10.1161/CIR.0b013e3181d4739e. PMID: 20233780.
- Um SW, Ohle R, Perry JJ. Bilateral blood pressure differential as a clinical marker for acute aortic dissection in the emergency department. Emerg Med J. 2018;35(9):556-558. doi: 10.1136/emermed-2018-207499. PMID: 30021832.
Welcome to the AIR ACS Module! After carefully reviewing all relevant posts from the top 50 sites of the Social Media Index, the ALiEM AIR Team is proud to present the highest quality online content related to ACS emergencies in the Emergency Department. 7 blog posts met our standard of online excellence and were curated and approved for residency training by the AIR Series Board. We identified 4 AIR and 3 Honorable Mentions. We recommend programs give 4 hours (about 30 minutes per article) of III credit for this module.
AIR Stamp of Approval and Honorable Mentions
In an effort to truly emphasize the highest quality posts, we have 2 subsets of recommended resources. The AIR stamp of approval is awarded only to posts scoring above a strict scoring cut-off of ≥30 points (out of 35 total), based on our scoring instrument. The other subset is for “Honorable Mention” posts. These posts have been flagged by and agreed upon by AIR Board members as worthwhile, accurate, unbiased, and appropriately referenced despite an average score.
Interested in taking the ACS quiz for fun or asynchronous (Individualized Interactive Instruction) credit? Please go to the above link. You will need to create a free, 1-time login account.
Highlighted Quality Posts: ACS Emergencies
|EM Cases||Reciprocal Change and Occlusion MI||Jesse McLaren, MD||10 Aug 2021||AIR|
|EM Cases||Wellen’s Syndrome, Re-occlusion, and MI||Jesse McLaren, MD||13 Jul 2021||AIR|
|EM Cases||HyperAcute T waves and Occlusion MI||Jesse McLaren, MD||4 May 2021||AIR|
|EM Cases||ST elevations mnemonic and Occlusion MI||Jesse McLaren, MD||12 Jan 2021||AIR|
|Rebel EM||The OMI/NOMI Paradigm||Salim Rezaie, MD and Tarlan Hedayati, MD||3 Oct 2021||HM|
|Dr. Smith’s ECG blog||Accuracy of OMI ECG findings versus STEMI criteria for diagnosis of acute OMI||Steve Smith, MD and Pendell Myers, MD||12 Apr 2021||HM|
|emDocs||Cocaine and ST elevation||Brannon Inman, MD and Lloyd Tannenbaum, MD||10 Dec 2020||HM|
(AIR = Approved Instructional Resource; HM = Honorable Mention)
Thank you to the Society of Academic Emergency Medicine (SAEM) and the Council of EM Residency Directors (CORD) for jointly sponsoring the AIR Series! We are thrilled to partner with both on shaping the future of medical education.