scholarly journals Quantifying cerebrovascular reactivity in anterior and posterior cerebral circulations during voluntary breath holding

2016 ◽  
Vol 101 (12) ◽  
pp. 1517-1527 ◽  
Author(s):  
Christina D. Bruce ◽  
Craig D. Steinback ◽  
Uday V. Chauhan ◽  
Jamie R. Pfoh ◽  
Maria Abrosimova ◽  
...  

Pain Medicine ◽  
2020 ◽  
Vol 21 (11) ◽  
pp. 3012-3017
Author(s):  
Igor Petrušić ◽  
Ana Podgorac ◽  
Aleksandra Radojičić ◽  
Jasna Zidverc-Trajković

Abstract Background Previous studies suggest that increased cerebrovascular reactivity might be a feature of patients who have migraine with aura (MwA). The correlation between the clinical presentation of migraine with aura and transcranial Doppler parameters remains unclear. Objective The main aim of this study was to explore cerebral blood flow, vascular resistance, and cerebrovascular reactivity in women MwA. Also, the relationships between hemodynamic conditions and aura characteristics are examined. Design Cross-sectional study. Setting Headache Center, Neurology Clinic, Clinical Center of Serbia. Subjects Fifty-four women MwA and 49 healthy controls (HCs). Methods Transcranial Doppler sonography examination was used to determine blood flow mean velocity (MV) and pulsatility index (PI), as well as breath-holding index (BHI), in 15 arterial segments comprising the circle of Willis. Results A total of 54 women MwA and 49 HCs were studied. The PIs of all segments of the left and right middle cerebral arteries and the left and right anterior cerebral arteries were significantly higher in MwA with regards to HCs. Also, both the left and right BHIs were significantly higher in MwA than HCs. In addition, MVs of the right vertebral artery and the first segment of the basilar artery were significantly lower in MwA than HCs. Longer duration of migraine aura showed a weak negative correlation with the PI of the left posterior cerebral artery. Conclusions Our findings suggest increased vessel pulsatility, abnormal cerebrovascular reactivity, and decreased cerebral blood flow velocity in several arterial segments of the Willis circle in women MwA.



2009 ◽  
pp. 383-392 ◽  
Author(s):  
P Kolář ◽  
J Neuwirth ◽  
J Šanda ◽  
V Suchánek ◽  
Z Svatá ◽  
...  

Using magnetic resonance imaging (MRI) in conjunction with synchronized spirometry we analyzed and compared diaphragm movement during tidal breathing and voluntary movement of the diaphragm while breath holding. Breathing cycles of 16 healthy subjects were examined using a dynamic sequence (77 slices in sagittal plane during 20 s, 1NSA, 240x256, TR4.48, TE2.24, FA90, TSE1, FOV 328). The amplitude of movement of the apex and dorsal costophrenic angle of the diaphragm were measured for two test conditions: tidal breathing and voluntary breath holding. The maximal inferior and superior positions of the diaphragm were subtracted from the corresponding positions during voluntary movements while breath holding. The average amplitude of inferio-superior movement of the diaphragm apex during tidal breathing was 27.3±10.2 mm (mean ± SD), and during voluntary movement while breath holding was 32.5±16.2 mm. Movement of the costophrenic angle was 39±17.6 mm during tidal breathing and 45.5±21.2 mm during voluntary movement while breath holding. The inferior position of the diaphragm was lower in 11 of 16 subjects (68.75 %) and identical in 2 of 16 (12.5 %) subjects during voluntary movement compared to the breath holding. Pearson’s correlation coefficient was used to demonstrate that movement of the costophrenic angle and apex of the diaphragm had a linear relationship in both examined situations (r=0.876). A correlation was found between the amplitude of diaphragm movement during tidal breathing and lung volume (r=0.876). The amplitude of movement of the diaphragm with or without breathing showed no correlation to each other (r=0.074). The movement during tidal breathing shows a correlation with the changes in lung volumes. Dynamic MRI demonstrated that individuals are capable of moving their diaphragm voluntarily, but the amplitude of movement differs from person to person. In this study, the movements of the diaphragm apex and the costophrenic angle were synchronous during voluntary movement of the diaphragm while breath holding. Although the sample is small, this study confirms that the function of the diaphragm is not only respiratory but also postural and can be voluntarily controlled.



Stroke ◽  
2001 ◽  
Vol 32 (suppl_1) ◽  
pp. 360-360
Author(s):  
Maria Perez Barreto ◽  
Glenn M Fischberg ◽  
Annlia Paganini-Hill ◽  
Yodchai Lapakulchai ◽  
Sebastian F Ameriso ◽  
...  

P118 Stroke risk is increased in the presence of some infections. We studied potential mechanisms linking infections and stroke risk. We used endotoxin, a component of gram negative bacteria, as a standardized inflammatory stimulus. We infused low-dose endotoxin (1ng/kg) as a bolus in four healthy men, and analyzed cerebrovascular and hemostatic effects over 24 hours. We measured cerebral vasomotor reactivity, using transcranial Doppler ultrasonography to calculate breath-holding index (BHI); the latter consists of the percent change of middle cerebral artery blood flow velocity over time during breath holding. We also measured thrombin-antithrombin complexes (TAT, an index of thrombin generation), and soluble e-selectin (a marker of endothelial activation). Following infusion of endotoxin, there were substantial physiological changes primarily at three to six hours post-infusion. Temperature peaked at 100 °F (p<.05), with no significant change in mean arterial pressure. BHI showed maximum decline from 1.55 ± 0.88 to 0.33 ± 0.35 %/sec (p<.05). TAT levels increased from 3.0 ± 0.9 to 41.0 ± 21.1 ug/ml (p<.05). Soluble e-selectin levels increased from 66.6 ± 35.2 to 207.4 ± 78.9 ug/ml (p<.05). These findings indicate that a standardized low-dose inflammatory stimulus produces a marked decline in human cerebrovascular reactivity while simultaneously inducing a procoagulant state with endothelial activation . The reduction in cerebrovascular reactivity combined with a procoagulant state may contribute to increased stroke risk in this setting.



1998 ◽  
Vol 60 (6) ◽  
pp. 671-679 ◽  
Author(s):  
Walton T. Roth ◽  
Frank H. Wilhelm ◽  
Werner Trabert


2015 ◽  
Vol 88 (1054) ◽  
pp. 20150309 ◽  
Author(s):  
Ruth Colgan ◽  
Matthew James ◽  
Frederick R Bartlett ◽  
Anna M Kirby ◽  
Ellen M Donovan


2019 ◽  
Author(s):  
Suk Tak Chan ◽  
Karleyton C. Evans ◽  
Tian Yue Song ◽  
Juliett Selb ◽  
Andre van der Kouwe ◽  
...  

AbstractHypercapnia during breath holding is believed to be the dominant driver behind the modulation of cerebral blood flow (CBF). Here we showed that the cerebrovascular responses to brief breath hold epochs were coupled not only with increased partial pressure of carbon dioxide (PCO2), but also with a decrease in partial pressure of oxygen (PO2). We used transcranial Doppler ultrasound to evaluate the CBF changes during breath holding by measuring the cerebral blood flow velocity (CBFv) in the middle cerebral arteries, a pair of cerebral arteries that supply most parts of the brain. The regional CBF changes during breath hold epochs were mapped with blood oxygenation level dependent (BOLD) signal changes as surrogate of CBF changes using functional magnetic resonance imaging (fMRI) technique. Given the interdependence of the dynamic changes between PCO2 and PO2, we found that the breath-by-breath O2-CO2 exchange ratio (bER), namely the ratio of changes in PO2 (ΔPO2) to changes in PCO2 (ΔPCO2) between end inspiration and end expiration, was superior to either ΔPO2 or ΔPCO2 alone in coupling with the changes of CBFv and BOLD signals under breath hold challenge. The regional cerebrovascular reactivity (CVR) results derived by regressing BOLD signal changes on bER under breath hold challenge resembled those derived by regressing BOLD signal changes on end-tidal partial pressure of CO2 (PETCO2) under exogenous CO2 challenge. Our findings provide a novel insight on the potential of using bER to better quantify CVR changes under breath hold challenge, although the physiological mechanisms of cerebrovascular changes underlying breath hold and exogenous CO2 challenges are potentially different.



PEDIATRICS ◽  
1985 ◽  
Vol 75 (1) ◽  
pp. 76-79
Author(s):  
Nick G. Anas ◽  
John T. McBride ◽  
Christian Boettrich ◽  
Kenneth McConnochie ◽  
John G. Brooks

The ability of children with cyanotic breath-holding spells to respond to anger or frustration by voluntary breath-holding for prolonged periods (often to the point of precipitating hypoxic seizure activity) suggested the hypothesis that such children may have a less powerful urge to breathe in the presence of hypoxia and/or hypercapnia than children who do not have breath-holding spells. Because ventilatory chemosensitivity is difficult to measure in infants and young children, this hypothesis was tested indirectly by measuring the ventilatory responses to hyperoxic progressive hypercapnia and to isocapnic progressive hypoxia of seven individuals who had a history of cyanotic breath-holding spells in infancy and 17 control subjects. The mean values for sensitivity to hypoxia and to hypercapnia were not significantly different between the two groups, and the responses of the majority of the subjects with cyanotic breath-holding spells were clearly within the normal range. There were fewer individuals with high-normal ventilatory responses among the subjects with cyanotic breath-holding spells. Although children with cyanotic breath-holding spells may have decreased ventilatory chemosensitivity transiently during infancy or may differ from other children in some other aspect of the control of breathing, the pathogenesis of infantile cyanotic breath-holding spells does not involve a permanently blunted sensitivity to hypercapnia or hypoxia.



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