When blood runs cold: cold agglutinins and cardiac surgery.

Cold agglutinins are particular cold-reactive antibodies that react with red blood cells when the blood temperature drops below normal body temperature causing increased blood viscosity and red blood cell clumping. Most individuals with cold agglutinins are not aware of their presence, as these antibodies have little effect on daily living, often necessitating no treatment. However, when those with cold agglutinins are exposed to hypothermic situations or undergo procedures such as cardiopulmonary bypass with hypothermia during cardiac surgery, lethal complications of hemolysis, microvascular occlusion and organ failure can occur. By identifying those suspected of possessing cold agglutinins through a comprehensive nursing assessment and patient history, cold agglutinin screening can be performed prior to surgery to determine a diagnosis of cold agglutinin disease. With a confirmed diagnosis of cold agglutinin disease, the plan of care can be focused on measures to maintain the patient's blood temperature above the thermal amplitude throughout their hospitalization including the use of normothermic cardiopulmonary bypass with warm myocardial preservation techniques to prevent these fatal complications. Using a case report approach, the authors review the mechanism, clinical manifestations, detection and nursing management of a patient with cold agglutinins undergoing scheduled cardiac surgery. Cold agglutinin disease is rare. However, the risk to patients warrants an increased awareness of cold agglutinins and screening for those who are suspected of carrying these antibodies.