My Husband Works Outside Everyday Running Bore Machines For Pipe

My husband works outside everyday running bore machines for pipe lines, etc. We thought frost bite but not anymore. His left hand is a tad swollen & looks tight almost even shiny. When he opens & closes, he says it feels tight as well. The color is off too. From nail to knuckle, it's more white. He also feels like he has a fever in it plus tingling that now goes up to the elbow. So... Poor circulation? It's been going on for 3-4 days. He thought nothing but now we are worried.