Cardiac arrest occurs when the heart suddenly stops beating and blood flow to the body is halted. It can occur while people are in the hospital because of a medical condition, or while people are out of the hospital as a result of an accident or other causes. Cardiac arrest is a serious event that is associated with high rates of death and long-term disability. When a person experiences cardiac arrest, insufficient amount of blood flow and oxygen can result in brain injury.~Therapeutic hypothermia is a therapy that involves a controlled lowering of the body temperature and then maintenance of this lower temperature for a period of time. The treatment may result in reduced brain injury. Therapeutic hypothermia has been successfully used in adults who experience cardiac arrest to improve survival rates and health outcomes, and it has also been studied in newborn infants who have suffered from perinatal asphyxia. The purpose of this study is to evaluate the efficacy of therapeutic hypothermia at improving survival rates and reducing brain injury in infants and children who experience cardiac arrest while out of the hospital.~Study researchers will conduct this study in collaboration with the following two pediatric clinical research networks: the Pediatric Emergency Care Applied Research Network (PECARN), funded by the Emergency Medical Services for Children (EMSC) program, and the National Institute of Child Health and Human Development (NICHD) Collaborative Pediatric Critical Care Research Network (CPCCRN).~The study will enroll infants and children who have suffered a cardiac arrest while out of the hospital. Randomization must occur within 6 hours of return of spontaneous circulation. Participants will be randomly assigned to receive either therapeutic hypothermia or therapeutic normothermia. Participants receiving therapeutic hypothermia will have their body temperature reduced to between 32 to 34° Celsius (C) and will remain at this temperature for 2 days. Their body temperature will then be slowly increased to the normal temperature of 36 to 37.5° C, which will be maintained until 5 days after the cardiac arrest. Participants receiving therapeutic normothermia will have their normal temperature maintained between 36 to 37.5° C for 5 days after the cardiac arrest. Special temperature control blankets will be placed to maintain body temperature in the assigned range. After 5 days, each participant's temperature will be managed by their medical care team.~While participants are in the hospital, they will undergo frequent blood and urine collections, chest x-rays, and temperature measurements; parents of participants will complete questionnaires. When participants are ready to leave the hospital, study researchers will perform a physical and functional assessment. Twenty-eight days after the cardiac arrest, researchers will contact parents of participants to gather information on the participants' health and medical condition. At Months 3 and 12, a child development expert will contact parents to gather medical information. At Month 12, participants will attend a study visit for a neurologic examination and testing with a psychologist trained in rehabilitation.
Cardiac arrest is a sudden, unexpected loss of heart function. Therapeutic hypothermia, in which the body's temperature is lowered and maintained several degrees below normal for a period of time, has been used to successfully treat adults who have experienced cardiac arrest. This study will evaluate the efficacy of therapeutic hypothermia at increasing survival rates and reducing the risk of brain injury in infants and children who experience a cardiac arrest while out of the hospital.