You are assessing a 26-year-old male pedestrian who was hit by a car.

Look at the vital signs pattern first: low blood pressure (86 systolic) + high pulse (128) . This tells you the body is no longer maintaining adequate perfusion , meaning compensation has failed.

In EMT training, compensated shock still has a normal blood pressure , even though heart rate and breathing increase. Once hypotension develops , the patient has progressed to decompensated shock .

So the key deciding factor here is the low BP , which makes this decompensated shock , not compensated.