Taccone Fabio Silvio, Su Fuhong, He Xinrong, Peluso Lorenzo, Donadello Katia, Scolletta Sabino, De Backer Daniel, Vincent Jean-Louis
Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium.
Laboratoire Experimental des Soins Intensifs, Department of Intensive Care, Hôpital Erasme, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium.
Biomedicines. 2022 Apr 18;10(4):923. doi: 10.3390/biomedicines10040923.
The effects of reversal of hypotension on the cerebral microcirculation, oxygenation, and metabolism in septic shock remain unclear. In 12 sheep, peritonitis was induced by injection of feces into the abdominal cavity. At the onset of septic shock (mean arterial pressure (MAP) < 65 mmHg, unresponsive to fluid challenge), a norepinephrine infusion was titrated in eight sheep to restore a MAP ≥ 75 mmHg; the other four sheep were kept hypotensive. The microcirculation of the cerebral cortex was evaluated using side-stream dark-field video-microscopy. Brain partial pressure of oxygen (PbtO2) was measured, and cerebral metabolism was assessed using microdialysis. All animals developed septic shock after a median of 15 (14−19) h. When MAP was raised using norepinephrine, the PbtO2 increased significantly (from 41 ± 4 to 55 ± 5 mmHg), and the cerebral lactate/pyruvate ratio decreased (from 47 ± 13 to 28 ± 4) compared with values at shock onset. Changes in the microcirculation were unchanged with restoration of MAP and the glutamate increased further (from 17 ± 11 to 23 ± 16 μM), as it did in the untreated animals. In septic shock, the correction of hypotension with vasopressors may improve cerebral oxygenation but does not reverse the alterations in brain microcirculation or cerebral metabolism.
在脓毒性休克中，纠正低血压对脑微循环、氧合及代谢的影响仍不明确。选用12只绵羊，通过向腹腔内注射粪便诱导腹膜炎。在脓毒性休克发作时（平均动脉压（MAP）<65 mmHg，对液体复苏无反应），8只绵羊用去甲肾上腺素静脉滴注使MAP恢复至≥75 mmHg；另外4只绵羊维持低血压状态。采用侧流暗视野视频显微镜评估大脑皮质的微循环。测量脑组织氧分压（PbtO2），并使用微透析评估脑代谢。所有动物在中位数为15（14 - 19）小时后均发生脓毒性休克。当使用去甲肾上腺素使MAP升高时，与休克发作时相比，PbtO2显著升高（从41±4 mmHg升至55±5 mmHg），脑乳酸/丙酮酸比值降低（从47±13降至28±4）。随着MAP恢复，微循环变化未改变，谷氨酸进一步升高（从17±11 μM升至23±16 μM），未治疗动物亦是如此。在脓毒性休克中，使用血管升压药纠正低血压可能改善脑氧合，但不能逆转脑微循环或脑代谢的改变。
