Critchley Giles R, Bell B Anthony
Department of Neurosurgery, Division of Clinical Neurosciences, Atkinson Morley's Hospital, London, UK.
Neurol Res. 2003 Jul;25(5):451-6. doi: 10.1179/016164103101201841.
Primary brain ischemia following subarachnoid hemorrhage is a major cause of morbidity and mortality. This study aims to determine whether changes in cerebral tissue oxygenation are related to cerebral blood flow changes in the acute phase following experimental subarachnoid hemorrhage. The endovascular puncture model was used to study subarachnoid hemorrhage in male Wistar rats with a tissue oxygenation probe and a laser Doppler probe placed contralateral to the side of hemorrhage. Following the subarachnoid hemorrhage intracranial pressure rose to 53.0 +/- 9.8 mmHg (mean +/- SEM). This was associated with a fall in cerebral blood flow to 43.9% +/- 7.1% of its baseline value and a fall in tissue oxygenation to 42.8% +/- 7.7% of baseline. The time course of the fall and recovery in tissue oxygenation was closely correlated to that of the cerebral blood flow (r = 0.66, p = 0.02). The fall in cerebral blood flow was associated with a 42.1% +/- 6.47% fall in the concentration of moving blood cells and a rise of 181.2% +/- 27.2% in velocity indicating acute microcirculatory vasoconstriction. Interstitial tissue oxygenation changes mirrored changes in cerebral blood flow indicating that a change in oxygen delivery was occurring.
蛛网膜下腔出血后的原发性脑缺血是发病和死亡的主要原因。本研究旨在确定实验性蛛网膜下腔出血急性期脑组织氧合变化是否与脑血流变化相关。采用血管内穿刺模型，对雄性Wistar大鼠进行蛛网膜下腔出血研究，在出血侧对侧放置组织氧合探头和激光多普勒探头。蛛网膜下腔出血后颅内压升至53.0±9.8 mmHg（平均值±标准误）。这与脑血流降至其基线值的43.9%±7.1%以及组织氧合降至基线的42.8%±7.7%相关。组织氧合下降和恢复的时间进程与脑血流密切相关（r = 0.66，p = 0.02）。脑血流下降与流动血细胞浓度下降42.1%±6.47%以及速度上升181.2%±27.2%相关，表明急性微循环血管收缩。间质组织氧合变化反映了脑血流变化，表明正在发生氧输送变化。
