Faculty Opinions recommendation of Increasing arterial blood pressure with norepinephrine does not improve microcirculatory blood flow: a prospective study.

✓ Intracranial pressure (ICP) and continuous transcranial Doppler ultrasound signals were monitored in 20 head-injured patients and simultaneous synchronous fluctuations of middle cerebral artery (MCA) velocity and B waves of the ICP were observed. Continuous simultaneous monitoring of MCA velocity, ICP, arterial blood pressure, and expired CO2 revealed that both velocity waves and B waves occurred despite a constant CO2 concentration in ventilated patients and were usually not accompanied by fluctuations in the arterial blood pressure. Additional recordings from the extracranial carotid artery during the ICP B waves revealed similar synchronous fluctuations in the velocity of this artery, strongly supporting the hypothesis that blood flow fluctuations produce the velocity waves. The ratio between ICP wave amplitude and velocity wave amplitude was highly correlated to the ICP (r = 0.81, p < 0.001). Velocity waves of similar characteristics and frequency, but usually of shorter duration, were observed in seven of 10 normal subjects in whom MCA velocity was recorded for 1 hour. The findings in this report strongly suggest that B waves in the ICP are a secondary effect of vasomotor waves, producing cerebral blood flow fluctuations that become amplified in the ICP tracing, in states of reduced intracranial compliance.

Download Full-text

Forearm and finger blood flow responses to passive body tilts

Journal of Applied Physiology ◽

10.1152/jappl.1979.46.2.288 ◽

1979 ◽

Vol 46 (2) ◽

pp. 288-292 ◽

Cited By ~ 12

Author(s):

Y. A. Mengesha ◽

G. H. Bell

Keyword(s):

Blood Pressure ◽

Blood Flow ◽

Arterial Blood Pressure ◽

Vascular Resistance ◽

Pulse Rate ◽

Forearm Blood Flow ◽

Body Tilt ◽

Finger Blood Flow ◽

Arterial Blood ◽

Forearm Vascular Resistance

Ten to fifteen healthy subjects, ages 18--30 yr, were used to assess the correlation of forearm blood flow with graded passive body tilts and vascular resistance and also to discern the relative effects of body tilts on finger blood flow. In the head-up tilts forearm blood flow and arterial blood pressure fell progressively, whereas forearm vascular resistance and pulse rate increased. In the head-down tilts the forearm blood flow and the arterial blood pressure increased, whereas the forearm vascular resistance and pulse rate decreased. These changes were found to be significantly correlated with the different tilt angles and with one another. In a preliminary study it was found that infrared heating of the carpometacarpal region produced finger vasodilatation similar to the forearm vasodilatation observed by Crockford and Hellon (6). However, unlike forearm blood flow, finger blood flow showed no appreciable response to either the head-up or head-down tilts. This indicates that the sympathetic tone and the volume of blood in the finger are not appreciably altered by this test procedure at least 1 min after the body tilt is assumed.

Download Full-text

Modeling Cerebral Blood Flow Dependence on Carbon Dioxide and Mean Arterial Blood Pressure in the Immature Brain With Accounting for the Germinal Matrix

Frontiers in Neurology ◽

10.3389/fneur.2018.00812 ◽

2018 ◽

Vol 9 ◽

Cited By ~ 7

Author(s):

Irina Sidorenko ◽

Varvara Turova ◽

Nikolai Botkin ◽

Laura Eckardt ◽

Ana Alves-Pinto ◽

...

Keyword(s):

Carbon Dioxide ◽

Blood Pressure ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Arterial Blood Pressure ◽

Mean Arterial Blood Pressure ◽

Immature Brain ◽

Germinal Matrix ◽

Arterial Blood ◽

Flow Dependence

Download Full-text

Effect of the Ace Inhibitor Ceronapril on Cerebral Blood flow in Hypertensive Patients

Annals of Pharmacotherapy ◽

10.1177/106002809603000601 ◽

1996 ◽

Vol 30 (6) ◽

pp. 578-582 ◽

Cited By ~ 5

Author(s):

Neal R Cutler ◽

John J Sramek ◽

Azucena Luna ◽

Ismael Mena ◽

Eric P Brass ◽

...

Keyword(s):

Blood Pressure ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Diastolic Blood Pressure ◽

Arterial Blood Pressure ◽

Mean Arterial Blood Pressure ◽

Enzyme Inhibitor ◽

Blood Pressure Response ◽

Combined Therapy ◽

Arterial Blood

Objective To assess the effect of the angiotensin-converting enzyme inhibitor ceronapril on cerebral blood flow (CBF) in patients with moderate hypertension. Design Patients received chlorthalidone 25 mg for 4 weeks, and if diastolic blood pressure remained in the range of 100–115 mm Hg, they were given titrated doses of ceronapril (10–40 mg/d based on blood pressure response) in addition to chlorthalidone for 9 weeks. Setting Outpatient research clinic. Subjects Eligible patients had moderate essential hypertension (diastolic blood pressure 100–115 mm Hg) assessed when the patients were receiving no medications. Thirteen patients were entered into the study; 1 withdrew for reasons unrelated to the study drug. Twelve patients (11 men, 1 woman; mean age 52 y) completed the study. Intervention Ceronapril, given with chlorthalidone. Main Outcome Measures CBF measurements were taken at the start and end of ceronapril therapy using intravenous 133Xe; blood pressures were determined weekly. Results Mean arterial blood pressure decreased from 130 ± 4 to 120 ±7 mm Hg after 4 weeks of chlorthalidone administration, and fell further to 108 ± 8 mm Hg after an additional 9 weeks of combined chlorthalidone-ceronapril therapy (p < 0.05). CBF fell from 44 ± 15 to 34 ± 5 mL/min/100 g during the 9 weeks of combined therapy (p = 0.05). No adverse effects consistent with decreased CBF were observed. The decrease in CBF was not linearly correlated with the change in systemic blood pressure, but was strongly correlated (r = –0.937; p < 0.001) with the initial CBF. Conclusions The decrease in mean arterial blood pressure was not associated with a decrease in CBF. Patients with high CBF may be predisposed to a decrease in CBF when treated with ceronapril and chlorthalidone.

Download Full-text