The frequency of mass casualty incidents has notably increased in recent years, with the COVID-19 pandemic exemplifying a critical surge in sudden cardiac arrests. This pandemic posed significant challenges for emergency medicine practitioners, providing essential lessons for global healthcare systems. Key insights emerged on the necessity for adaptability, preparedness, accessibility to medical resources, and efficient team coordination and collaboration among healthcare professionals. Ensuring effective management of mass casualties and optimizing team coordination within emergency departments (ED) requires continual review and updating of procedures and protocols. Such measures are vital to guarantee the best possible outcomes for those impacted by these incidents. This abstract underscores the imperative for healthcare systems to integrate these lessons into their operational frameworks to enhance their response capabilities in the face of future mass casualty events.