Contributor:  Don Stader, MD Educational Pearls: High-quality compressions are an essential, and probably one of the most important, part of cardiac arrest  Actual evidence for drugs in cardiac arrest included in ACLS are limited, including epinephrine, bicarbonate, amiodarone, etc. Early defibrillation for ventricular tachycardia (VT) or ventricular fibrillation (VF) has a plethora of supporting evidence Double-sequential defibrillation (nearly simultaneous defibrillation using 2 machines) may be considered for refractory dysrhythmias like VF tPA during a cardiac arrest can be considered in the setting of massive PE (although the evidence supporting this practice is poor) Ending a cardiac arrest resuscitation is a difficult decision and use of ultrasound may be helpful to assess for meaningful cardiac function/activity References Link MS, Berkow LC, Kudenchuk PJ, Halperin HR, Hess EP, Moitra VK, Neumar RW, O'Neil BJ, Paxton JH, Silvers SM, White RD, Yannopoulos D, Donnino MW . Part 7: Adult Advanced Cardiovascular Life Support: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2015 Nov;132(18 Suppl 2):S444-64.  Wang Y, Wang M, Ni Y, Liang B, Liang Z. Can Systemic Thrombolysis Improve Prognosis of Cardiac Arrest Patients During Cardiopulmonary Resuscitation? A Systematic Review and Meta-Analysis.J Emerg Med. 2019;57(4):478. Epub 2019 Oct 5.  Eric Cortez, William Krebs, James Davis, David P. Keseg, Ashish R. Panchal. Use of double sequential external defibrillation for refractory ventricular fibrillation during out-of-hospital cardiac arrest. Resuscitation. Volume 108. 2016. Pages 82-86, Atkinson PR, Beckett N, French J, Banerjee A, Fraser J, Lewis D. Does Point-of-care Ultrasound Use Impact Resuscitation Length, Rates of Intervention, and Clinical Outcomes During Cardiac Arrest? A Study from the Sonography in Hypotension and Cardiac Arrest in the Emergency Department (SHoC-ED) Investigators. Cureus. 2019;11(4):e4456. Published 2019 Apr 13. doi:10.7759/cureus.4456 Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD