Hypothermia (lowering of body temperature) decreases the metabolic requirement of vital organs. Hence it is possible to clamp the aorta for a longer period with hypothermia. If a longer procedure time is anticipated, hypothermia is a useful adjunct to cardiovascular surgery. In small infants, hypothermia is used to do surgery under total circulatory arrest. This gives a better surgical field in a small heart by avoiding the tubes used for cardiopulmonary bypass. Cooling can be done using a heart lung machine as well as a hypothermia blanket.
