Augmented Physiologic Monitoring to Predict Brain Injury in Infants with CHD

描述(申请人提供)：新型非侵入性光学仪器，包括近红外光谱(NIRS)和漫反射相关光谱(DCS)，提高了我们实时测量脑血流动力学和氧合的能力。近红外光谱测量脑氧合已迅速被临床所接受，但尚未得到严格的研究。用于测量脑血流的分布式控制系统，是光学成像领域的一项较新的创新。结合使用分布式控制系统和近红外光谱系统，扩大了我们研究早期心脏手术后临床护理如何影响脑血流动力学和脑代谢的能力。此外，使用分布式控制系统持续评估脑血流量，我们将能够通过与平均动脉压进行新的时间序列相关分析来评估大脑自动调节。脑自动调节是一种保护性机制，粗略地定义为尽管全身血压波动，但仍能保持持续和充足的脑血流的能力，可能会因危重疾病而变得功能障碍。使用这些新的光学仪器，我们计划研究脑室周围白质软化(PVL)形式的脑损伤的时间和原因，这些婴儿患有需要婴儿心脏手术的严重形式的先天性心脏病(CHD)。在患有先天性心脏病的婴儿中，手术前PVL损伤的发生率为20%，手术后的PVL损伤发生率略高于50%。通过监测婴幼儿心脏手术后脑组织血氧、血流和代谢，我们将探讨CHD患者发生新的或恶化的PVL损伤的脑血流动力学危险因素。更好地了解这一人群中PVL的发生时间和原因将有助于医生制定治疗或预防它的策略。此外，从这项研究中获得的知识将有助于为其他“高危”婴儿群体设计研究，例如早产儿或有过分娩创伤的婴儿。

DESCRIPTION (provided by applicant): Novel non-invasive optical instrumentation including near infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) increase our ability to measure cerebral hemodynamics and oxygenation in real time. NIRS measurement of cerebral oxygenation has been rapidly accepted into clinical practice, but has not been rigorously studied. DCS for measuring cerebral blood flow, is a more recent innovation in optical imaging. Used in combination DCS and NIRS expand our capability to study how cerebral hemodynamics and cerebral metabolism are affected by clinical care following early heart surgery. Further, using DCS to continuously assess cerebral blood flow we will be able to assess cerebral autoregulation by performing new time-series correlation analysis with mean arterial blood pressure. Cerebral autoregulation is a protective mechanism loosely defined as the ability to maintain constant and adequate cerebral blood flow despite fluctuations in systemic blood pressures, may become dysfunctional as a consequence of critical illness. Using these new optical instruments we plan to study the timing and causes of brain injury in the form of periventricular leukomalacia (PVL) in infants with severe forms congenital heart defects (CHD) that require infant heart surgery. In infants with CHD the PVL injury occurs in 20% before surgery and just over 50% afterwards. By monitoring brain tissue blood oxygenation, flow, and metabolism after infant heart surgery, we will investigate the cerebral hemodynamic risk-factors for developing new or worsened PVL injury in CHD patients. A better understanding of the timing and causes of PVL in this population will help physicians build strategies to treat or prevent it. Furthermore, the knowledge gained from this study will help design studies for other 'at- risk' populations of infants, such as premature infants or infants who have had birth trauma.