A Review on Cerebral Autoregulation Assessment and Measurements

Cerebral Autoregulation (CA) is the intrinsic ability of the brain to maintain stable cerebral blood flow (CBF) while mean arterial blood pressure (MAP) and cerebral perfusion pressure (CPP) are changing. It constitutes a regulatory mechanism to provide metabolic substrates under physiological and pathological conditions, for instance after neuro-trauma or spontaneous intra-cranial haemorrhage. Constant CBF is regulated by changing arteriolar diameter, which will alter cerebral blood volume (CBV) and, ultimately, intra-cranial pressure (ICP). On the other hand, ICP is the sum of the partial pressures of brain tissue, cerebrospinal fluid (CSF) and CBV