TY - JOUR
T1 - Reduced regional and global cerebral blood flow during fenoldopam-induced hypotension in volunteers
AU - Prielipp, Richard C.
AU - Wall, Michael H.
AU - Groban, Leanne
AU - Tobin, Joseph R.
AU - Fahey, Frederic H.
AU - Harkness, Beth A.
AU - Stump, David A.
AU - James, Robert L.
AU - Cannon, Mark A.
AU - Bennett, Judy
AU - Butterworth, John
PY - 2001
Y1 - 2001
N2 - 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 α2-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 α2-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 μg · 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 · 100g-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.
AB - 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 α2-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 α2-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 μg · 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 · 100g-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.
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U2 - 10.1097/00000539-200107000-00011
DO - 10.1097/00000539-200107000-00011
M3 - Article
C2 - 11429337
AN - SCOPUS:0034950487
SN - 0003-2999
VL - 93
SP - 45
EP - 52
JO - Anesthesia and analgesia
JF - Anesthesia and analgesia
IS - 1
ER -