Objectives: To assess the diagnostic utility and effectiveness of the RUSH protocol for identifying shock in the Emergency Department (ED) setting. Background: hock is a clinical syndrome that must be recognized and managed as early as possible. Each shock subtype requires a distinct therapeutic approach, so the clinician must accurately determine which form of shock the patient has. Point‑of‑care ultrasound enables physicians to directly visualize and clarify the underlying cause of shock. Methods: Between April 2022 and April 2024, this prospective study evaluated 100 patients presenting with shock at Menoufia University Hospitals' ED. All participants were initially managed using the ABCDE clinical framework to identify and stabilize life threatening conditions. Subsequently, the RUSH protocol was implemented as the primary diagnostic tool to determine the specific etiology of each patient's shock. Results: One hundred shocked patients were included (traumatic and non‑traumatic); 66% were male, 34% female, with mean age 51.8±15.11 years. In traumatic shock, RUSH correctly identified 100% of cardiogenic and obstructive, 93.33% of hypovolemic, 80% of mixed, and 77.77% of distributive cases (Kappa 0.777–1). In non‑traumatic shock, RUSH correctly identified 100% of obstructive, 90.00% of cardiogenic, 88.89% of hypovolemic, 87.5% of mixed, and 83.33% of distributive cases (Kappa 0.731–1). Conclusion: RUSH protocol serves as an efficient and dependable technique for determining the underlying cause of a patient's hemodynamic instability.