Abstract: This invention provides a device and method for cooling an internal organ during surgery. The device involves a porous, water-permeable net, preferably made of hydrophilic elastic fabric. The net is fitted and secured around the organ and cold saline solution is infused into the net, preferably by means of a side-hole catheter. The cold liquid passes through the net, directly contacting and chilling the organ. As the liquid drips out of the net, it is removed from the patient's chest or abdomen by suction tube. To provide convenient access to any location on the surface of the organ (for example, to operate on a coronary artery which must be bypassed) a cut is made through a part of the net overlying the location that must be operated on. This exposes the artery without affecting the ability of the net to cool the rest of the organ.