Cerebral blood flow velocity during simultaneous changes in mean arterial pressure and cardiac output in healthy volunteers

摘要: Cerebral blood flow (CBF) needs to be precisely controlled maintain brain functions. While previously believed autoregulated and near constant over a wide pressure range, CBF is now understood as more passive. However, there are still questions regarding the integrated nature of regulation specifically role cardiac output. Our aim was, therefore, explore effects MAP output on in combined model reduced preload increased afterload. 16 healthy volunteers were exposed combinations different levels simultaneous lower body negative isometric hand grip. We measured velocity middle cerebral artery (MCAV) internal carotid (ICAV) by Doppler ultrasound, oxygen saturation (ScO2) near-infrared spectroscopy, surrogates for CBF. The effect changes was estimated with mixed multiple regression. Both had independent MCAV, ICAV ScO2. For ScO2 also statistically significant interaction between change 10 mmHg MCAV 3.11 cm/s (95% CI 2.51–3.71, P < 0.001), 1 L/min 3.41 cm/s 2.82–4.00, P < 0.001). present study indicates that during reductions output, both have