Low body temperature during surgery, defined as a temperature below 34 °C, occurs commonly in patients undergoing cardiac surgery due to the bypass machine and an open chest. Low body temperature has been associated with blood loss, but the relevant published data are inconclusive. Nevertheless, evidence suggests that blood loss during and after surgery are higher in low body temperature patients than in the normal body temperature patients. In addition, low body temperature can impair blood clotting. The clinical significance of this is high as it is well established that blood transfusion increases mortality after surgery.
This study will investigate how chest temperature relates to blood loss and blood clotting. Researchers will use infra-red thermometers to measure the temperature of the chest at the end of surgery see if this relates to the amount of blood collected from the surgical drains. In addition, researchers will test if warm irrigation of the chest increases the temperature of the chest and if this impacts blood loss.