A nurse is assessing a client who is postoperative following a coronary artery bypass graft surgery. The nurse should identify that which of the following findings is an early indication of cardiac tamponade?

A. Coarse lung sounds: These are indicative of secretions in the larger airways and may suggest fluid overload or pulmonary complications but are not specific to cardiac tamponade and are considered a later or unrelated finding in this context. B. Decreased jugular vein distention: Accumulation of fluid in the pericardial sac compresses the heart and impairs its ability to fill typically causing increased jugular venous pressure, so a decrease would not be expected and does not indicate early tamponade. C. Widening pulse pressure: Narrowing, not widening, of the pulse pressure is more characteristic of cardiac tamponade due to decreased stroke volume and rising intrapericardial pressure. D. Muffled heart sounds: This is a classic early sign of cardiac tamponade caused by fluid accumulation in the pericardial sac, which dampens the sound of the heart during auscultation. This is one of the key components of Beck's triad, along with hypotension and elevated jugular venous pressure.