Alterations in Cerebral Blood Flow in Preterm Infants with Intraventricular Hemorrhage

PEDIATRICS ◽  
1981 ◽  
Vol 68 (6) ◽  
pp. 763-769
Author(s):  
Laura R. Ment ◽  
Richard A. Ehrenkranz ◽  
Robert C. Lange ◽  
Peter T. Rothstein ◽  
Charles C. Duncan
Keyword(s):  
Computed Tomography ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Ct Scan ◽  
Preterm Infants ◽  
Intraventricular Hemorrhage ◽  
Mean Value ◽  
Germinal Matrix ◽  
The Mean ◽  
Xenon 133

Xenon-133 inhalation hemispheric cerebral blood flow (HCBF) determinations at one to two days and four to six days postnatally and at 37 weeks postconceptual age have been correlated with computed tomography (CT) scan and autopsy findings in 15 preterm infants weighing less than 1,250 gm at birth. Ten of these infants had germinal matrix hemorrhages (GMH) or intraventricular hemorrhages (IVH). Although HCBF obtained at one to two days showed no mean difference between the GMH/IVH group and the nonhemorrhage infants, hemispheric flow ratios showed significant discrepancies in the GMH/IVH group. In addition, in four of five patients in whom the hemorrhage appeared asymmetric on CT scan, the side of higher flow correlated with the hemorrhage. At four to six days HCBF showed a lower mean value in the GMH/IVH patients than in the nonhemorrhage patients and differences in the interhemispheric ratios in the GMH/IVH group persisted. There were no differences in the mean HCBF values or hemispheric ratios between the two groups of infants at 37 weeks postconceptual age.

Vasospasm and Regional Cerebral Blood Flow (rCBF) in Patients with Ruptured Intracranial Aneurysm: Serial rCBF Studies with the Xenon-133 Inhalation Method

Neurosurgery ◽  
1983 ◽  
Vol 13 (4) ◽  
pp. 394-401 ◽  
Author(s):  
Iwao Yamakami ◽  
Katsumi Isobe ◽  
Akira Yamaura ◽  
Takao Nakamura ◽  
Hiroyasu Makino
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Neurological Deficit ◽  
Mean Value ◽  
Initial Slope ◽  
Delayed Ischemic Neurological Deficit ◽  
Ruptured Intracranial Aneurysm ◽  
The Mean ◽  
Xenon 133 ◽  
Head Probe

Abstract To clarify the relationship of vasospasm to the reduction of cerebral blood flow (CBF) and the delayed ischemic neurological deficit, serial rCBF studies with the use of the xenon-133 inhalation method were conducted in 35 postoperative patients with ruptured intracranial aneurysms. The CBF was calculated as an initial slope index (ISI) derived from the desaturation curve of each head probe, and the hemispheric mean value of the ISI (mean ISI) was calculated in both hemispheres. The mean ISI in the hemisphere ipsilateral to the operation was low compared to that of the contralateral hemisphere. In relation to the presence of vasospasm, angiographic findings were classified into the following five types: diffuse, peripheral, proximal-severe, proximal-mild, and no spasm. Patients with vasospasm of the diffuse, peripheral, and proximal-severe types showed a markedly decreased mean ISI, and vasospasm of the diffuse type caused the greatest degree of reduction. The mean ISI of the patients who developed delayed ischemic neurological deficit (DIND) due to vasospasm was significantly decreased (37.4± 4.6) compared to that of the patients who did not develop DIND (52.2± 5.6). None of 3 cases of no spasm and only 1 of 14 cases of proximal-mild spasm developed DIND. On the other hand, all of 4 cases of diffuse, 2 of 3 cases of peripheral, and 2 of 6 cases of proximal-severe spasm developed DIND. Thus, if these three types of vasospasm are joined together as severe vasospasm, 8 of 13 cases with severe vasospasm developed DIND. These results suggest that severe vasospasm causes a reduction of CBF and that the reduced CBF brings about DIND.

The Use of Stable Xenon-Enhanced Computed Tomographic Studies of Cerebral Blood Flow to Define Changes in Cerebral Carbon Dioxide Vasoresponsivity Caused by a Severe Head Injury

Neurosurgery ◽  
1991 ◽  
Vol 29 (6) ◽  
pp. 869-873 ◽  
Author(s):  
Donald W. Marion ◽  
Gerrit J. Bouma
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Head Injury ◽  
Severe Head Injury ◽  
Brain Structures ◽  
Computed Tomographic ◽  
Stable Xenon ◽  
Scale Scores ◽  
The Mean ◽  
Xenon 133

Abstract Previous studies using the xenon-133 cerebral blood flow (CBF) method have documented the impairment of CO2vasoresponsivity after a severe head injury, but only global values can be obtained reliably with this technique. We studied CO2vasoresponsivity using the stable xenon-enhanced computed tomographic CBF method, which provided information about well-defined cortical regions and deep brain structures not available with the xenon-133 method. In 17 patients with admission Glasgow Coma Scale scores of 8 or less, hemispheric CO2vasoresponsivity ranged from 1.3 to 8.5% per mm Hg change in partial CO2pressure. Lobar, cerebellar, basal ganglia, and brain stem CO2vasoresponsivity frequently varied from the mean global value by more than 25%. In all but one patient, local CO2vasoresponsivity in one or more of these areas differed from the mean global value by more than 50%. The greatest variability occurred in patients with acute subdural hematomas and diffuse (bihemispheric) injuries. This variability in CO2vasoresponsivity has important implications for the effective and safe management of intracranial hypertension that frequently accompanies severe head injury.

Hemorrhage, Phenobarbital, and Fluctuating Cerebral Blood Flow

PEDIATRICS ◽  
1989 ◽  
Vol 83 (4) ◽  
pp. 645-646
Author(s):  
JEFFREY M. PERLMAN ◽  
JOSEPH J. VOLPE ◽  
A. ERNEST ◽  
JANE G. STEIN
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Coefficient Of Variation ◽  
Intraventricular Hemorrhage ◽  
Recent Article ◽  
Cerebral Blood Flow Velocity ◽  
Single Cycle ◽  
The Mean

In the recent article regarding fluctuating cerebral blood flow velocity and the intraventricular hemorrhage in the neonate, the authors concluded "when the best 20 waves are chosen to evaluate the coefficient of variation, no association exists between the coefficient of variation values and development of subependymal-intraventricular hemorrhage...." Such a conclusion is clearly not justified based on the data presented. First, the mean mode as was used in this study is an averaged frequency for a single cycle.

scholarly journals Mathematical modeling of the hematocrit influence on cerebral blood flow in preterm infants

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261819
Author(s):  
Irina Sidorenko ◽  
Varvara Turova ◽  
Esther Rieger-Fackeldey ◽  
Ursula Felderhoff-Müser ◽  
Andrey Kovtanyuk ◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Preterm Infants ◽  
Blood Viscosity ◽  
Intraventricular Hemorrhage ◽  
Clinical Care ◽  
Diagnostic Tools ◽  
Vessel Resistance

Premature birth is one of the most important factors increasing the risk for brain damage in newborns. Development of an intraventricular hemorrhage in the immature brain is often triggered by fluctuations of cerebral blood flow (CBF). Therefore, monitoring of CBF becomes an important task in clinical care of preterm infants. Mathematical modeling of CBF can be a complementary tool in addition to diagnostic tools in clinical practice and research. The purpose of the present study is an enhancement of the previously developed mathematical model for CBF by a detailed description of apparent blood viscosity and vessel resistance, accounting for inhomogeneous hematocrit distribution in multiscale blood vessel architectures. The enhanced model is applied to our medical database retrospectively collected from the 254 preterm infants with a gestational age of 23–30 weeks. It is shown that by including clinically measured hematocrit in the mathematical model, apparent blood viscosity, vessel resistance, and hence the CBF are strongly affected. Thus, a statistically significant decrease in hematocrit values observed in the group of preterm infants with intraventricular hemorrhage resulted in a statistically significant increase in calculated CBF values.

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