The first thing that came to mind when I was thinking about the use of color was the show Dexter. They use red so often to show blood spatter that the viewer can lose focus on the intensity the color is creating. I choose to use the scene when Dexter is working in a hotel room and keeps imaging the room filled with blood, just like the pool of blood he was born in in the shipping container.
This scene is a good example color because the red spattered all over the white room shows the torture and evil that lives in Dexter's memory. The red is able to stand out and draw your attention when being used on a white background.
I think the biggest impact by the color and the blood is the symbolism of the river of blood that flows through the middle of the room. I believe it signifies Dexter being drawn into these horrible memories by the current of the bloody river. The river also makes the viewer feel as if they can feel the vast emptiness inside of Dexter.
As Dexter is continually brought back to this image every time he enters the hotel room, I believe the viewer can get a deeper and better connection with his past. The scene does not surprise the viewer because of the great amount of blood (since the entire show is very bloody already), the blood creates thought and brings a little of relatability to the character.