EM Quick Hits 12 AFib Early vs Delayed Cardioversion, Snake Bites, Ovarian Torsion Myths, Crystal Meth, Aortic Dissection, Severe Asthma Meds

Topics in this EM Quick Hits podcast Paul Dorion on immediate cardioversion vs rate control/delayed cardioversion for atrial fibrillation (00:32) Justin Morgenstern & Justin Hensley on emergency management of snake bites (10:24) Brit Long on reliability of clinical features in the diagnosis of ovarian torsion (21:35) Michelle Klaiman on emergency management of crystal methamphetamine use disorder (26:48) Hans Rosenberg & Rob Ohle on workup of suspected aortic dissection (32:16) Anand Swaminathan on epinephrine and magnesium sulphate in severe asthma (38:05) Podcast production, editing and sound design by Anton Helman Podcast content, written summary & blog post by Sucheta Sinha, Michelle Klaiman & Brit Long, edited by Anton Helman Cite this podcast as: Helman, A. Dorion, P.  Swaminathan, A. Long, B.  Klaiman, M. Rosenberg, H, Hensley, J. Ohle, R. Morgenstern J. EM Quick Hits 12 - AFib Early vs Delayed Cardioversion, Snake Bites, Ovarian Torsion Myths, Crystal Meth, Aortic Dissection, Severe Asthma Meds. Emergency Medicine Cases. January, 2020. https://emergencymedicinecases.com/em-quick-hits-january-2020/. Accessed [date]. Immediate cardioversion vs rate control and delayed cardioversion for acute atrial fibrillation * For stable patients who present to the ED with the primary diagnosis of rapid atrial fibrillation with moderate to severe symptoms and no complications mandating immediate cardioversion (heart failure, cardiac ischemia, shock) options include electrical or chemical cardioversion or rate control with delayed cardioversion. * Arguments for immediate electrical cardioversion include high success rate and prompt resolution of symptoms. * Support for immediate ED cardioversion comes from the recent RAF2 trial which compared two strategies for cardioversion (rhythm control) in acute-onset atrial fibrillation: 1) procainamide infusion + shock vs 2) placebo fluid infusion + shock. Both were similarly effective (>93%) in converting to sinus rhythm and 95% of patients remained in sinus rhythm even 2 weeks afterwards. * It is unclear whether or not the risk of stroke is reduced, increased or uneffected with cardioversion in the ED compared to rate control. * Arguments against immediate cardioversion include high ED resource utilization, potential rare complications associated with procedural sedation and that most patients spontaneously convert without intervention within 36hrs (about 70%). * Our expert believes that encouraging patients with uncomplicated primary atrial fibrillation to return to the ED for cardioversion whenever they have symptoms of atrial fibrillation results many unnecessary ED visits and be an unnecessary burden on the system. * Support for withholding immediate cardioversion comes from a 2019 NEJM study which compared immediate ED cardioversion to rate control and reassessment within 36hrs for consideration of delayed cardioversion (going home with a rate control agent) if still in atrial fibrillation. 91% of patients in the delayed cardioversion group were in sinus rhythm at 1 month and 94% in the immediate cardioversion group,  showing non-inferiority. There was no differences in potential risks or patient-reported quality of life between the two strategies. * Practical considerations such as availability of follow up within 36hrs limits the "delayed" cardioversion strategy.