Fetal aortic to middle cerebral artery resistance index ratio: An indicator of normal and pathologic arterial blood flow distribution

2000 ◽  
Vol 70 ◽  
pp. B60-B60
Author(s):  
J. Aranyosi ◽  
T. Major ◽  
J. Zatik ◽  
P. Bettembuk
Keyword(s):  
Blood Flow ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Resistance Index ◽  
Flow Distribution ◽  
Arterial Blood Flow ◽  
Blood Flow Distribution ◽  
Arterial Blood ◽  
Index Ratio

scholarly journals Fetal Aortic-cerebral Doppler Resistance Index Ratio: An Indicator of Physiologic Blood Flow Distribution

2009 ◽  
Vol 3 (3) ◽  
pp. 91-96
Author(s):  
Zoltán Tóth ◽  
János Aranyosi ◽  
Tamás Deli ◽  
Péter Bettembuk ◽  
Bence Kozma ◽  
...  
Keyword(s):  
Blood Flow ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Resistance Index ◽  
Flow Distribution ◽  
Arterial Blood Flow ◽  
Blood Flow Distribution ◽  
Descending Aorta ◽  
Arterial Blood ◽  
Index Ratio

Abstract Identical hemodynamic impedance and constant ratio of the fetal descending aorta and middle cerebral artery of uncomplicated pregnancies at term. Fetal aortic-cerebral Doppler resistance index ratio: An indicator of physiologic blood flow distribution. Objective To interpret the physiologic fetal arterial blood flow distribution by relating the vascular impedance of the fetal descending aorta (DA) and middle cerebral artery (MCA) and to establish the reference ranges for the aortic-cerebral Doppler resistance index ratio (ACRI). Study design Ninety-six patients with uncomplicated pregnancies were recruited for the cross-sectional assessment of the Doppler resistance index (RI) in the fetal DA and MCA between the 38rd and 40th weeks of gestation. The normal ranges of the ACRI were calculated. A cut-off value was designed to facilitate the clinical application of the ACRI. Results Between the 38th and 40th weeks of gestation in normal pregnancies the ACRI of healthy fetuses is constant, the overall mean is: 1.062 (+/– 0.087). A single cut-off value of 1.2 is recommended to assist separating normal and pathologic arterial blood flow patterns. Conclusion The normal ACRI reflects the identical vascular resistance of the descending aorta and the cerebral vessels, which maintains the physiologic fetal central arterial blood flow. Additional clinical studies are necessary to assess the diagnostic efficacy of the abnormal ACRI (>1.2) as a potentially useful marker of the centralized arterial circulation indicating the early stage of fetal hypoxemic jeopardy.

scholarly journals Probabilistic Anatomic Mapping of Cerebral Blood Flow Distribution of the Middle Cerebral Artery

2007 ◽  
Vol 49 (1) ◽  
pp. 39-43 ◽  
Author(s):  
S.-J. Kim ◽  
I.-J. Kim ◽  
Y.-K. Kim ◽  
T.-H. Lee ◽  
J. S. Lee ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Flow Distribution ◽  
Blood Flow Distribution

scholarly journals Assessment of maternal cerebral blood flow in patients with preeclampsia

2005 ◽  
Vol 58 (1-2) ◽  
pp. 68-71 ◽  
Author(s):  
Vesna Mandic ◽  
Zeljko Mikovic` ◽  
Milan Djukic ◽  
Mladenko Vasiljevic ◽  
Dejan Filimonovic ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Magnesium Sulfate ◽  
Cerebral Artery ◽  
Resistance Index ◽  
Severe Preeclampsia ◽  
Arterial Blood Flow ◽  
Clinical Test ◽  
Flow Measurements ◽  
Arterial Blood

Introduction Systemic vasoconstrktion in preeclamptic patients increases vascular resistance, and is manifested by increased arterial blood flow velocity. The aim of the study is to evaluate if there is a change of Doppler indices in maternal medial cerbral artery (MCA) in severe preeclampsia due to: 1) severity of clinical symptoms, 2) the beginning of eclamptic attack and 3) the application of anticonvidsive therapy. Material and methods A prospective clinical study included 92 pregnant women, gestational age 28-36 weeks. They were divided into three groups: normotensive (n=30), mild preeclampsia (n=33), and severe preeclampsia (n=29). We investigated maternal cerebral circulation by assessing the MCA. We registrated: pulsatility index (Pi), resistance index (Ri), Systolic/diastolic ratio (S/D), and the maximum systolic, end diastolic and medium velocity. Patients with severe preeclampsia were divided into two subgroups: subgroup 1 included patients without symptoms of threatening eclampsia (n=18; 62.06%); while subgroup 2 included those with symptoms of preeclampsia (n=11; 37.94%). All patients with severe preeclampsia were treated with magnesium sulfate (MgSO4), and cerebral blood flow was measured before and after the treatment. Statistical analysis was done by oneway ANOVA, Student t-test and t-paired sample test. The difference was considered to be significant if p < 0.05. Results Significantly increased Pi, Ri and all velocities were established in the group of patients with severe preeclampsia compared with the other two groups. In the group with severe preeclamsia we registrated significantly increased values of all velocities (patients with signs of threatening eclampsia). After MgSO4 treatment in patients with severe preeclampsia significantly decreased values of Pi, Ri, S/D ratio and all velocities were registered. Discussion In the studied group of patients with severe preclampsia we found increased velocity values, Pi and Ri, especially in patients with signs of threatened eclampsia, suggesting that blood vessels changes are most prominent in severe preeclampsia. Cerebral blood flow measurements can be used as a clinical test for the prediction of eclampsia. Magnesium-sulfate (MgSO4) has a significant role in prophylaxis and treatment of eclampsia, and, therefore, positive influence on reduction of cerebral ishemic lesions can be expected. Conclusion We can conclude that changes of the cerebral blood flow can be evaluated by evaluating blood flow velocities in the medial cerebral artery. Velocities tend to increase in severe preeclampsia, especially with signs of threatening eclampsia, and decrease after treatment with magnesium sulfate. Serial measurements of blood flow in medial cerebral artery in patients with severe preeclampsia may be used in prediction of eclampsia and in evaluation of magnesium sulfate therapy effects.

Effects of Sufentanil on Cerebral Hemodynamics and Intracranial Pressure in Patients with Brain Injury

1995 ◽  
Vol 83 (4) ◽  
pp. 721-726. ◽  
Author(s):  
Christian Werner ◽  
Eberhard Kochs ◽  
Hanswerner Bause ◽  
William E. Hoffman ◽  
Jochen Schulte am Esch
Keyword(s):  
Blood Flow ◽  
Middle Cerebral Artery ◽  
Flow Velocity ◽  
Cerebral Artery ◽  
Blood Flow Velocity ◽  
Artery Blood Flow ◽  
Arterial Blood ◽  
Norepinephrine Infusion ◽  
Group 2 ◽  
Group 1

Background The current study investigates the effects of sufentanil on cerebral blood flow velocity and intracranial pressure (ICP) in 30 patients with intracranial hypertension after severe brain trauma (Glasgow coma scale &lt; 6). Methods Mechanical ventilation (FIO2 0.25-0.4) was adjusted to maintain arterial carbon dioxide tensions of 28-30 mmHg. Continuous infusion of midazolam (200 micrograms/kg/h intravenous) and fentanyl (2 micrograms/kg/h intravenous) was used for sedation. Mean arterial blood pressure (MAP, mmHg) was adjusted using norepinephrine infusion (1-5 micrograms/min). Mean blood flow velocity (Vmean, cm/s) was measured in the middle cerebral artery using a 2-MHz transcranial Doppler sonography system. ICP (mmHg) was measured using an epidural probe. After baseline measurements, a bolus of 3 micrograms/kg sufentanil was injected, and all parameters were continuously recorded for 30 min. The patients were assigned retrospectively to the following groups according to their blood pressure responses to sufentanil: group 1, MAP decrease of less than 10 mmHg, and group 2, MAP decrease of more than 10 mmHg. Results Heart rate, arterial blood gases, and esophageal temperature did not change over time in all patients. In 18 patients, MAP did not decrease after sufentanil (group 1). In 12 patients, sufentanil decreased MAP &gt; 10 mmHg from baseline despite norepinephrine infusion (group 2). ICP was constant in patients with maintained MAP (group 1) but was significantly increased in patients with decreased MAP. Vmean did not change with sufentanil injection regardless of changes in MAP. Conclusions The current data show that sufentanil (3 micrograms/kg intravenous) has no significant effect on middle cerebral artery blood flow velocity and ICP in patients with brain injury, intracranial hypertension, and controlled MAP. However, transient increases in ICP without changes in middle cerebral artery blood flow velocity may occur concomitant with decreases in MAP. This suggests that increases in ICP seen with sufentanil may be due to autoregulatory decreases in cerebral vascular resistance secondary to systemic hypotension.

Adenosine and cerebral capillary perfusion and blood flow during middle cerebral artery occlusion

1989 ◽  
Vol 257 (5) ◽  
pp. H1656-H1662
Author(s):  
M. Anwar ◽  
H. R. Weiss
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Brain Regions ◽  
Artery Occlusion ◽  
Capillary Perfusion ◽  
Arterial Blood ◽  
Cerebral Artery Occlusion

The effects of adenosine on regional cerebral blood flow and indexes of the total and perfused microvascular bed were studied after 1 h of middle cerebral artery occlusion in the anesthetized rat. Iodo[14C]antipyrine was used to determine cerebral blood flow. Fluorescein isothiocyanate-dextran was used to study the perfused microvasculature, and an alkaline phosphatase stain was used to identify the total bed. Mean arterial blood pressure was significantly reduced by adenosine. Cerebral blood flow increased significantly by 75%, except in the flow-restricted cortex where flow averaged 28 +/- 15 (SD) ml.min-1.100 g-1 in control and 34 +/- 33 ml.min-1.100 g-1 in adenosine-treated animals. No significant regional structural differences were observed within the microvascular beds of the two groups. The percentage of the microvascular volume perfused increased significantly in all brain regions in the adenosine-treated rats, including the flow-restricted cortex. The percent perfused arteriolar volume in the flow-restricted cortex was 30 +/- 12% in control and 95 +/- 3% in adenosine-treated animals. Similar values for the capillary bed were 22 +/- 10% in control and 54 +/- 3% in adenosine-treated rats. These results indicate a maintenance of flow with a reduction in diffusion distances in the flow-restricted cortex after treatment with adenosine.

Redistribution of blood flow after thermal injury and hemorrhagic shock

1988 ◽  
Vol 65 (4) ◽  
pp. 1782-1788 ◽  
Author(s):  
E. A. Carter ◽  
R. G. Tompkins ◽  
M. L. Yarmush ◽  
W. A. Walker ◽  
J. F. Burke
Keyword(s):  
Blood Flow ◽  
Hemorrhagic Shock ◽  
Intestinal Mucosa ◽  
Thermal Injury ◽  
Burn Injury ◽  
Flow Distribution ◽  
Arterial Blood Flow ◽  
Arterial Blood ◽  
Mucosal Mass ◽  
Small And Large Intestine

Diminished mucosal mass and a diminished rate of DNA synthesis by the intestinal mucosa have been identified in the rat after thermal injury. Because these changes may be associated with ischemia, the distribution of intestinal blood flow was studied after a thermal injury and compared with the blood flow distribution after hemorrhagic shock. For the thermal injury, anesthetized animals received a standardized 20% body surface area, full-thickness injury and were given intraperitoneal saline resuscitation. By the use of 46Sc- or 141Ce-labeled microspheres, no changes in intestinal and hepatic blood flow occurred after thermal injury. In contrast, a marked redistribution of blood flow was identified after hemorrhagic shock in which a decrease in arterial blood flow was identified to the stomach and to the small and large intestine. Although clinical shock was not present, the cardiac output decreased to a comparable degree in the hemorrhagic shock and the thermal injury. These studies indicate that although physiological changes in intestinal mucosa can be demonstrated after burn injury, these changes are not due to decreases in mesenteric arterial blood flow.

scholarly journals Is there any influence of breastfeeding on the cerebral blood flow? A review of 256 healthy newborns

2012 ◽  
Vol 45 (5) ◽  
pp. 263-266 ◽  
Author(s):  
Alexandra Maria Vieira Monteiro ◽  
Claudio Marcio Amaral de Oliveira Lima ◽  
Paula Medina
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Pulsatility Index ◽  
Cerebral Blood Flow Velocity ◽  
Resistance Index ◽  
Left Middle Cerebral Artery ◽  
Mean Velocity ◽  
The Right

OBJECTIVE: To investigate whether breastfeeding influence the cerebral blood-flow velocity. MATERIALS AND METHODS: The present study included 256 healthy term neonates, all of them with appropriate weight for gestational age, 50.8% being female. Pulsatility index, resistance index and mean velocity were measured during breastfeeding or resting in the anterior cerebral artery, in the left middle cerebral artery, and in the right middle cerebral artery of the neonates between their first 10 and 48 hours of life. The data were analyzed by means of a paired t-test, Brieger's f-test for analysis of variance and linear regression, with p < 0.01 being accepted as statistically significant. RESULTS: Mean resistance index decreased as the mean velocity increased significantly during breastfeeding. Pulsatility index values decreased as much as the resistance index, but in the right middle cerebral artery it was not statistically significant. CONCLUSION: Breastfeeding influences the cerebral blood flow velocities.

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