Non-invasive Assessment of Cerebral Blood Flow and Oxygen Metabolism in Neonates during Hypothermic Cardiopulmonary Bypass: Feasibility and Clinical Implications

Silvina L. Ferradal, Koichi Yuki, Rutvi Vyas, Christopher G. Ha, Francesca Yi, Christian Stopp, David Wypij, Henry H. Cheng, Jane W. Newburger, Aditya K. Kaza, Maria A. Franceschini, Barry D. Kussman (+1 others)
2017 Scientific Reports  
The neonatal brain is extremely vulnerable to injury during periods of hypoxia and/or ischemia. Risk of brain injury is increased during neonatal cardiac surgery, where pre-existing hemodynamic instability and metabolic abnormalities are combined with long periods of low cerebral blood flow and/ or circulatory arrest. Our understanding of events associated with cerebral hypoxia-ischemia during cardiopulmonary bypass (CPB) remains limited, largely due to inadequate tools to quantify cerebral
more » ... en delivery and consumption non-invasively and in real-time. This pilot study aims to evaluate cerebral blood flow (CBF) and oxygen metabolism (CMRO 2 ) intraoperatively in neonates by combining two novel non-invasive optical techniques: frequency-domain near-infrared spectroscopy (FD-NIRS) and diffuse correlation spectroscopy (DCS). CBF and CMRO 2 were quantified before, during and after deep hypothermic cardiopulmonary bypass (CPB) in nine neonates. Our results show significantly decreased CBF and CMRO 2 during hypothermic CPB. More interestingly, a change of coupling between both variables is observed during deep hypothermic CPB in all subjects. Our results are consistent with previous studies using invasive techniques, supporting the concept of FD-NIRS/DCS as a promising technology to monitor cerebral physiology in neonates providing the potential for individual optimization of surgical management. Given its critical functions, the brain is the ultimate organ whose outcome must be optimized in any operating room or intensive care setting. All surgical and medical management strategies must be designed to prevent or at least minimize brain injury. Neonates undergoing cardiac surgery with cardiopulmonary bypass (CPB) are particularly vulnerable to hypoxic-ischemic brain injury 1-3 . Since CPB requires periods of reduced systemic flow and/ or circulatory arrest, cerebral hypothermia is routinely used with a primary goal to reduce cerebral oxygen consumption, such that the risk of hypoxic-ischemic brain injury is minimized. Laboratory and human studies have
doi:10.1038/srep44117 pmid:28276534 pmcid:PMC5343476 fatcat:qgr4ykqn5ffzdapge5jwirum5e