Icing is an important technique to help minimize pain and reducing swelling from an Wrist Pain – Carpal Tunnel Syndrome. Again it is a pain-reliever not a treatment or ergonomic technique.
I liked to put ice cubes in a pitcher of cold water and dunk my hand, wrist, and upper arm into the cold ice water. This gets the entire area iced thoroughly. My hands needed to feel almost numb before they were removed from the ice water. As some put it, when you are numb, you are done. I found that I need to ice longer than I did previously.
Hot and Cold transition baths are also a good way to increase circulation due to Carpal Tunnel Syndrome problems.
This site has some good times on how to make icing work well for Carpal Tunnel Syndrome sufferers.
You can read more about icing and how long to ice from this guide to Repetitive Strain Injury. Wrist Pain – Carpal Tunnel Syndrome takes time to heal, so lay off the computer.