Feddersen Berend, Neupane Pritam, Thanbichler Florian, Hadolt Irmgard, Sattelmeyer Vera, Pfefferkorn Thomas, Waanders Robb, Noachtar Soheyl, Ausserer Harald
Department of Neurology, Klinikum Grosshadern, University of Munich, Munich, Germany.
Department of Palliative Medicine, Specialized Palliative Home Care Team, University of Munich, Munich, Germany.
J Cereb Blood Flow Metab. 2015 Nov;35(11):1846-51. doi: 10.1038/jcbfm.2015.142. Epub 2015 Jun 17.
Symptoms of acute mountain sickness (AMS) may appear above 2,500 m altitude, if the time allowed for acclimatization is insufficient. As the mechanisms underlying brain adaptation to the hypobaric hypoxic environment are not fully understood, a prospective study was performed investigating neurophysiological changes by means of near infrared spectroscopy, electroencephalograpy (EEG), and transcranial doppler sonography at 100, 3,440 and 5,050 m above sea level in the Khumbu Himal, Nepal. Fourteen of the 26 mountaineers reaching 5,050 m altitude developed symptoms of AMS between 3,440 and 5,050 m altitude (Lake-Louise Score ⩾3). Their EEG frontal beta activity and occipital alpha activity increased between 100 and 3,440 m altitude, i.e., before symptoms appeared. Cerebral blood flow velocity (CBFV) in the anterior and middle cerebral arteries (MCAs) increased in all mountaineers between 100 and 3,440 m altitude. During further ascent to 5,050 altitude, mountaineers with AMS developed a further increase in CBFV in the MCA, whereas in all mountaineers CBFV decreased continuously with increasing altitude in the posterior cerebral arteries. These results indicate that hypobaric hypoxia causes different regional changes in CBFV despite similar electrophysiological changes.
如果适应时间不足，急性高原病（AMS）症状可能会出现在海拔2500米以上。由于大脑适应低压低氧环境的机制尚未完全明确，因此在尼泊尔昆布喜马拉雅地区进行了一项前瞻性研究，利用近红外光谱、脑电图（EEG）和经颅多普勒超声，在海拔100米、3440米和5050米处调查神经生理变化。在抵达海拔5050米的26名登山者中，有14人在海拔3440米至5050米之间出现了急性高原病症状（Lake-Louise评分⩾3）。在海拔100米至3440米之间，即在症状出现之前，他们的脑电图额叶β活动和枕叶α活动增加。在海拔100米至3440米之间，所有登山者大脑前动脉和大脑中动脉（MCA）的脑血流速度（CBFV）均增加。在进一步上升至海拔5050米的过程中，患有急性高原病的登山者大脑中动脉的脑血流速度进一步增加，而在所有登山者中，大脑后动脉的脑血流速度随海拔升高持续下降。这些结果表明，尽管电生理变化相似，但低压低氧会导致脑血流速度出现不同的区域变化。
