Eichhorn Lars, Erdfelder Felix, Kessler Florian, Doerner Jonas, Thudium Marcus O, Meyer Rainer, Ellerkmann Richard K
Department of Anaesthesiology and Intensive Care Medicine, University Hospital Bonn, Bonn, Germany.
Department of Radiology, University Hospital Bonn, Bonn, Germany.
J Clin Monit Comput. 2015 Dec;29(6):749-57. doi: 10.1007/s10877-015-9662-2. Epub 2015 Feb 4.
In this study we investigated the responsiveness of near-infrared spectroscopy (NIRS) recordings measuring regional cerebral tissue oxygenation (rSO2) during hypoxia in apneic divers. The goal was to mimic dynamic hypoxia as present during cardiopulmonary resuscitation, laryngospasm, airway obstruction, or the "cannot ventilate cannot intubate" situation. Ten experienced apneic divers performed maximal breath hold maneuvers under dry conditions. SpO2 was measured by Masimo™ pulse oximetry on the forefinger of the left hand. NIRS was measured by NONIN Medical's EQUANOX™ on the forehead or above the musculus quadriceps femoris. Following apnea median cerebral rSO2 and SpO2 values decreased significantly from 71 to 54 and from 100 to 65%, respectively. As soon as cerebral rSO2 and SpO2 values decreased monotonically the correlation between normalized cerebral rSO2 and SpO2 values was highly significant (Pearson correlation coefficient = 0.893). Prior to correlation analyses, the values were normalized by dividing them by the individual means of stable pre-apneic measurements. Cerebral rSO2 measured re-saturation after termination of apnea significantly earlier (10 s, SD = 3.6 s) compared to SpO2 monitoring (21 s, SD = 4.4 s) [t(9) = 7.703, p < 0.001, r(2) = 0.868]. Our data demonstrate that NIRS monitoring reliably measures dynamic changes in cerebral tissue oxygen saturation, and identifies successful re-saturation faster than SpO2. Measuring cerebral rSO2 may prove beneficial in case of respiratory emergencies and during pulseless situations where SpO2 monitoring is impossible.
在本研究中，我们调查了近红外光谱（NIRS）记录在窒息潜水员缺氧期间测量局部脑组织氧合（rSO2）的反应性。目的是模拟心肺复苏、喉痉挛、气道阻塞或“无法通气无法插管”情况中出现的动态缺氧。10名经验丰富的窒息潜水员在干燥条件下进行最大屏气动作。通过Masimo™脉搏血氧饱和度仪测量左手食指的SpO2。通过NONIN Medical公司的EQUANOX™在前额或股四头肌上方测量NIRS。窒息后，大脑rSO2和SpO2的中位数分别从71%显著降至54%和从100%显著降至65%。一旦大脑rSO2和SpO2值单调下降，标准化的大脑rSO2和SpO2值之间的相关性就非常显著（皮尔逊相关系数 = 0.893）。在进行相关性分析之前，通过将这些值除以窒息前稳定测量的个体均值进行标准化。与SpO2监测（21秒，标准差 = 4.4秒）相比，窒息终止后大脑rSO2测量的再饱和明显更早（10秒，标准差 = 3.6秒）[t(9) = 7.703，p < 0.001，r(2) = 0.868]。我们的数据表明，NIRS监测能够可靠地测量脑组织氧饱和度的动态变化，并且比SpO2更快地识别成功的再饱和。在呼吸紧急情况以及无法进行SpO2监测的无脉情况下，测量大脑rSO2可能证明是有益的。
