Cardiopulmonary bypass is considered to be the common culprit for the occurrence of fever in the immediate post-operative period i.e, within 24 hours in pediatric patients. Other common causes contributing to fever are anaesthetic drugs, blood transfusions & pain. This early fever usually manifests as tachy-arrthymias in recovery room requiring interventions. This review intends to know the pathophysiology of fever and systemic inflammatory response syndrome after bypass (SIRAB) onset, preventive aspect…