志愿者在使用非诺多泮诱导低血压期间，局部和整体脑血流量降低。

Reduced regional and global cerebral blood flow during fenoldopam-induced hypotension in volunteers.

作者信息

Prielipp R C, Wall M H, Groban L, Tobin J R, Fahey F H, Harkness B A, Stump D A, James R L, Cannon M A, Bennett J, Butterworth J

机构信息

Department of Anesthesiology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1009, USA.

出版信息

Anesth Analg. 2001 Jul;93(1):45-52. doi: 10.1097/00000539-200107000-00011.

DOI:10.1097/00000539-200107000-00011

PMID:11429337

Abstract

UNLABELLED

Dopamine has a wide spectrum of receptor and pharmacologic actions that may affect cerebral blood flow (CBF). A new, selective dopamine-1 agonist, fenoldopam, is a potent systemic vasodilator with moderate alpha(2)-receptor affinity. However, the effects of fenoldopam on the cerebral circulation are undefined. We therefore hypothesized that infusion of fenoldopam would decrease mean arterial blood pressure (MAP) and might concurrently decrease CBF via vascular alpha(2)-adrenoreceptor activation in awake volunteers. We studied nine healthy normotensive subjects, using positron emission tomography to measure CBF in multiple cortical and subcortical regions of interest. In addition, bioimpedance cardiac output and middle cerebral artery blood flow velocity were determined during fenoldopam-induced hypotension. Three men and four women, aged 25-43 yr, completed the study. Fenoldopam infused at 1.3 +/- 0.4 microg. kg(-1). min(-1) (mean +/- SD) reduced MAP 16% from baseline: from 94 (89-100) mm Hg (mean [95% confidence interval]) to 79 [74-85] mm Hg (P < 0.0001). During the fenoldopam infusion, both cardiac output (+39%), and heart rate (+45%) increased significantly, whereas global CBF decreased from baseline, 45.6 [35.6-58.5] mL. 100 g(-1). min(-1), to 37.7 [33.9-42.0] mL. 100 g(-1). min(-1) (P < 0.0001). Despite restoration of baseline MAP with a concurrent infusion of phenylephrine, global CBF remained decreased relative to baseline values at 37.9 [34.0-42.3] mL. 100 gm(-1). min(-1) (P < 0.0001). Changes in middle cerebral artery velocity did not correlate with positron emission tomography-measured changes of CBF induced by fenoldopam, with or without concurrent phenylephrine.

IMPLICATIONS

In awake volunteers with (presumably) intact cerebral autoregulation,fenoldopam-induced hypotension significantly decreased global cerebral bloodflow (CBF). Clinicians should be aware of these pharmacodynamic effects when choosing a vasodilator to control blood pressure, especially in situations where control of CBF, cerebral blood volume, and intracranial pressure are therapeutic priorities.

摘要

未标注

多巴胺具有广泛的受体和药理作用，可能会影响脑血流量（CBF）。一种新型的选择性多巴胺 -1 激动剂非诺多泮是一种强效的全身血管扩张剂，对α₂受体具有中等亲和力。然而，非诺多泮对脑循环的影响尚不清楚。因此，我们推测在清醒志愿者中输注非诺多泮会降低平均动脉血压（MAP），并可能通过血管α₂肾上腺素能受体激活同时降低CBF。我们研究了 9 名健康的血压正常受试者，使用正电子发射断层扫描来测量多个感兴趣的皮质和皮质下区域的CBF。此外，在非诺多泮诱导的低血压期间测定生物阻抗心输出量和大脑中动脉血流速度。3 名男性和 4 名女性，年龄在 25 - 43 岁之间，完成了该研究。以 1.3±0.4 μg·kg⁻¹·min⁻¹（平均值±标准差）输注非诺多泮使 MAP 从基线降低了 16%：从 94（89 - 100）mmHg（平均值[95%置信区间]）降至 79[74 - 85]mmHg（P < 0.0001）。在输注非诺多泮期间，心输出量（+39%）和心率（+45%）均显著增加，而全脑CBF 从基线的 45.6[35.6 - 58.5]mL·100g⁻¹·min⁻¹降至 37.7[33.9 - 42.0]mL·100g⁻¹·min⁻¹（P < 0.0001）。尽管通过同时输注去氧肾上腺素恢复了基线 MAP，但相对于基线值，全脑CBF 仍降低至 37.9[34.0 - 42.3]mL·100g⁻¹·min⁻¹（P < 0.0001）。无论是否同时使用去氧肾上腺素，大脑中动脉速度的变化与非诺多泮诱导的CBF 变化（通过正电子发射断层扫描测量）均无相关性。