A 25 yr old man came to emergency depament after A. On CXR, multiple ribs fractures were visible. On physical examination, blood pressure was 80/60 mmHg and hea rate 150/min. Patient was restless, and tachypneic with jugular veins distended. On auscultation, air entry equal on both sides, hea sounds very soft or inaudible. What is the immediate step of management?