Extracerebral multiple organ dysfunction and interactions with brain injury after cardiac arrest

Cardiac arrest and successful resuscitation cause whole-body ischemia and reperfusion, leading to brain injury and extracerebral multiple organ dysfunction. Brain injury is the leading cause of death and long-term disability in resuscitated survivors, and was conceptualized and treated as an isolated injury, which has neglected the brain-visceral organ crosstalk. Extracerebral organ dysfunction is common and is significantly associated with mortality and poor neurological prognosis after resuscitation. However, detailed description of the characteristics of post-resuscitation multiple organ dysfunction is lacking, and the bidirectional interactions between brain and visceral organs need to be elucidated to explore new treatment for neuroprotection. This review aims to describe current concepts of post-cardiac arrest brain injury and specific characteristics of post-resuscitation dysfunction in cardiovascular, respiratory, renal, hepatic, adrenal, gastrointestinal, and neurohumoral systems. Additionally, we discuss the crosstalk between brain and extracerebral organs, especially focusing on how visceral organ dysfunction and other factors affect brain injury progression. We think that clarifying these interactions is of profound significance on how we treat patients for neural/systemic protection to improve outcome.