Final answer:
In a patient with acute pericarditis, jugular venous distention (JVD) to jaw level should be reported immediately as it suggests potential cardiac tamponade, a severe condition requiring prompt medical attention.
Step-by-step explanation:
The finding that should be reported immediately to the health care provider when assessing a patient with acute pericarditis is jugular venous distention (JVD) to jaw level. This can indicate an increase in venous pressure and possible cardiac tamponade, a life-threatening condition. Both pulsus paradoxus (a drop in blood pressure during inspiration) and chest pain are common findings in pericarditis; however, a JVD to jaw level suggests worsening cardiac condition that may require urgent intervention. While the elevated blood pressure reading is concerning, it is not typically associated with acute worsening in pericarditis as JVD to jaw level would be.