Jailyn Avila and Ben Smith discuss a recent Core Ultrasound YouTube lecture on diagnosing pericardial effusions and cardiac tamponade with point-of-care ultrasound, emphasizing its importance in emergency medicine and cardiac arrest. The Reason trial (PMID: 27693280; Romolo Gasparin et al) demonstrates improved survival to ROSC when pericardial effusion is identified with ultrasound—a finding that contrasts sharply with Beck's triad, which shows poor sensitivity. Emergency department–based studies reveal that all three Beck's triad signs are rarely present simultaneously. The RUSH/HIMAP approach offers a structured assessment framework. Blind pericardiocentesis in PEA without prior ultrasound confirmation should be avoided. Key tamponade findings include: a dilated plethoric IVC with minimal collapse, RV diastolic collapse (including RVOT assessment and M-mode timing with valve opening), right atrial diastolic collapse, and ultrasound assessment of pulsus paradoxus—a finding more useful for ruling out tamponade than confirming it.