McKinley Richard A, Tripp Lloyd D, Bolia Steve D, Roark Marvin R
Aircrew Performance and Protection Branch, Air Force Research Laboratory, 2215 First St., Bldg. 33, Wright-Patterson AFB, OH 45433-7947, USA.
Aviat Space Environ Med. 2005 Aug;76(8):733-8.
Failure to effectively regulate BP and cerebral perfusion during high-G aircraft maneuvering may contribute to reduced performance in pilots due to the fact that perfusion to the peripheral cerebral tissues may not be adequate to support the mental demands of flight. Therefore, a critical area of investigation is the study of cortical tissue oxygenation responses to +Gz acceleration.
Two experiments were used to build two sections of a cerebral oxygen saturation (rSo2) model. Experiment 1: Six subjects participated in the study. A cerebral oximeter (gold standard) provided rSo2. Acceleration profiles (subjects relaxed) included a 0.1 G x s(-1) G onset to central light loss (CLL) and a 3 G x s(-1) onset to a G level that was 1 Gz above CLL to an endpoint of G-LOC. Experiment 2: There were 12 subjects (with G protection) who participated in this study. The rSo2 data were collected during five different simulated aerial combat maneuvers. A model was created that read the Gz profile as input and calculated changes in rSo2. The correlation coefficient, linear best-fit slope, and mean percent error were calculated to determine agreement.
The average value for the correlation coefficients, linear best-fit slopes, and mean percent errors for the unprotected subjects were 0.79, 0.87, and 6.08, respectively. These values for the protected subjects were 5 G (0.994, 1.011, 0.384), 6 G (0.994, 0.909, 0.811), 7 G (0.986, 1.061, 0.692), 8 G (0.969, 1.016, 1.300), and 9 G (0.994, 0.979, 0.558), respectively.
The model is a good predictor of rSo2 values for protected and unprotected subjects under +Gz stress.
在高G值飞机机动过程中，若无法有效调节血压和脑灌注，可能会导致飞行员表现下降，因为外周脑组织的灌注可能不足以满足飞行的精神需求。因此，一个关键的研究领域是研究皮质组织氧合对+Gz加速度的反应。
通过两个实验构建了脑氧饱和度（rSo2）模型的两个部分。实验1：六名受试者参与研究。使用脑血氧仪（金标准）提供rSo2。加速度曲线（受试者放松状态）包括从0.1 G·s⁻¹加速到中心视力丧失（CLL），以及从3 G·s⁻¹加速到比CLL高1 Gz的G值水平直至G-LOC终点。实验2：12名受试者（有G值防护）参与本研究。在五种不同的模拟空战机动过程中收集rSo2数据。创建了一个模型，该模型将Gz曲线作为输入并计算rSo2的变化。计算相关系数、线性最佳拟合斜率和平均百分比误差以确定一致性。
未受防护受试者的相关系数、线性最佳拟合斜率和平均百分比误差的平均值分别为0.79、0.87和6.08。受防护受试者在5 G（0.994、1.011、0.384）、6 G（0.994、0.909、0.811）、7 G（0.986、1.061、0.692）、8 G（0.969、1.016、1.300）和9 G（0.994、0.979、0.558）时的这些值分别为上述对应值。
该模型是+Gz应激下受防护和未受防护受试者rSo2值的良好预测指标。
