Bair Hugger is a type of forced-air patient warming blanket. It consists of a standalone unit rests on the ground, and blows hot air into a tube. The tube is connected to an inflatable blanket. The blanket is full of tiny holes to let the air out. So the unit blows hot air into the blanket, and the hot air then hisses out of the holes in the blanket. This process provides a steady stream of warm air that warms the patient. It looks like this:
There are a variety of configurations for the Bair Hugger, including full-body, upper-body, or lower body blankets.
The problem is, the floor of the operating room is not sterile. And hot air rises. So when you heat up the contaminated air near the floor, it rises to the site of the surgery, causing infections.