A young man had a stab injury in left 5th ICS at the mid clavicular line. On examination there is no deviation of trachea, heart sounds diminished, systolic BP is 80 mmHg, and RR is 20/min. The diagnosis is

(A) Cardiac tamponade# Cardiac tamponade is a clinical syndrome caused by the accumulation of fluid in the pericardial space, resulting in reduced ven-tricular filling and subsequent hemodynamic compromise.> 3 phases of hemodynamic changes in tamponade.> Phase I: The accumulation of pericardial fluid causes increased stiffness of the ventricle, requiring a higher filling pressure. During this phase, the left and right ventricular filling pressures are higher than the intrapericardial pressure.> Phase II: With further fluid accumulation, the pericardial pressure increases above the ventricular filling pressure, resulting in reduced cardiac output.> Phase III: A further decrease in cardiac output occurs, which is due to equilibration of pericardial and left ventricular (LV) filling pressures.> Beck triad or acute compression triad This complex of physical findings refers to increased jugular venous pressure, hypotension & diminished heart sounds These findings result from a rapid accumulation of pericardial fluid. However, this classic triad is usually observed in patients with acute cardiac tamponade.> Pulsus paradoxus or paradoxical pulse: This is an exaggeration (>12 mm Hg or 9%) of the normal inspiratory decrease in systemic blood pressure