| Autor: |
Panerai RB; Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.; NIHR Leicester Biomedical Research Centre, BHF Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK., Barnes SC; Department of Cardiovascular Sciences, University of Leicester, Leicester, UK., Batterham AP; Department of Cardiovascular Sciences, University of Leicester, Leicester, UK., Robinson TG; Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.; NIHR Leicester Biomedical Research Centre, BHF Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK., Haunton VJ; Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.; NIHR Leicester Biomedical Research Centre, BHF Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK. |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism [J Cereb Blood Flow Metab] 2023 Apr; Vol. 43 (4), pp. 552-564. Date of Electronic Publication: 2022 Nov 24. |
| DOI: |
10.1177/0271678X221142527 |
| Abstrakt: |
Directional sensitivity, the more efficient response of cerebral autoregulation to increases, compared to decreases, in mean arterial pressure (MAP), has been demonstrated with repeated squat-stand maneuvers (SSM). In 43 healthy subjects (26 male, 23.1 ± 4.2 years old), five min. recordings of cerebral blood velocity (bilateral Doppler ultrasound), MAP (Finometer), end-tidal CO 2 (capnograph), and heart rate (ECG) were obtained during sitting (SIT), standing (STA) and SSM. A new analytical procedure, based on autoregressive-moving average models, allowed distinct estimates of the autoregulation index (ARI) by separating the MAP signal into its positive (MAP +D ) and negative (MAP -D ) derivatives. ARI +D was higher than ARI -D (p < 0.0001), SIT: 5.61 ± 1.58 vs 4.31 ± 2.16; STA: 5.70 ± 1.24 vs 4.63 ± 1.92; SSM: 4.70 ± 1.11 vs 3.31 ± 1.53, but the difference ARI +D -ARI -D was not influenced by the condition. A bootstrap procedure determined the critical number of subjects needed to identify a significant difference between ARI +D and ARI -D , corresponding to 24, 37 and 38 subjects, respectively, for SSM, STA and SIT. Further investigations are needed on the influences of sex, aging and other phenotypical characteristics on the phenomenon of directional sensitivity of dynamic autoregulation. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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