Influence of cerebral blood flow on breathing stability

Our previous work showed a diminished cerebral blood flow (CBF) response to changes in PaCO2 in congestive heart failure patients with central sleep apnea compared with those without apnea. Since the regulation of CBF serves to minimize oscillations in H+ and Pco2 at the site of the central chemoreceptors, it may play an important role in maintaining breathing stability. We hypothesized that an attenuated cerebrovascular reactivity to changes in PaCO2 would narrow the difference between the eupneic PaCO2 and the apneic threshold PaCO2 (ΔPaCO2), known as the CO2 reserve, thereby making the subjects more susceptible to apnea. Accordingly, in seven normal subjects, we used indomethacin (Indo; 100 mg by mouth) sufficient to reduce the CBF response to CO2 by ∼25% below control. The CO2 reserve was estimated during non-rapid eye movement (NREM) sleep. The apnea threshold was determined, both with and without Indo, in NREM sleep, in a random order using a ventilator in pressure support mode to gradually reduce PaCO2 until apnea occurred. results: Indo significantly reduced the CO2 reserve required to produce apnea from 6.3 ± 0.5 to 4.4 ± 0.7 mmHg ( P = 0.01) and increased the slope of the ventilation decrease in response to hypocapnic inhibition below eupnea (control vs. Indo: 1.06 ± 0.10 vs. 1.61 ± 0.27 l·min−1·mmHg−1, P < 0.05). We conclude that reductions in the normal cerebral vascular response to hypocapnia will increase the susceptibility to apneas and breathing instability during sleep.

Download Full-text

Cerebral Blood Flow Reactivity to Changes in Carbon Dioxide Calculated Using End-Tidal versus Arterial Tensions

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1991.171 ◽

1991 ◽

Vol 11 (6) ◽

pp. 1031-1035 ◽

Cited By ~ 54

Author(s):

William L. Young ◽

Isak Prohovnik ◽

Eugene Ornstein ◽

Noeleen Ostapkovich ◽

Richard S. Matteo

Keyword(s):

Carbon Dioxide ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Cerebrovascular Reactivity ◽

Noninvasive Measurement ◽

Moderate Correlation ◽

The Difference ◽

Highly Correlated ◽

End Tidal

We retrospectively examined arterial and endtidal estimations of CO2 tension used to calculate cerebrovascular reactivity in 68 anesthetized patients. CBF was measured using the intravenous 133Xe technique at mean ± SD Paco2 values of 28.2 ± 5.2 and 38.8 ± 4.8 mm Hg. The correlation between all Paco2 and end-tidal Pco2 (Petco2) values was y = 0.85 x −0.49 ( r = 0.93, p = 0.0001). There was a moderate correlation between age and the difference between Paco2 and Petco2 ( y = 0.11 x + 0.79; r = 0.73, p = 0.0001). Cerebrovascular reactivity to changes in CO2 (ml 100 g−1 min−1 mm Hg−1) was similar (p = 0.358) when calculated by using either Paco2 (1.9 ± 0.8) or Petco2 (1.8 ± 0.8) and highly correlated ( y = 0.86 x + 0.23; r = 0.91, p = 0.0001). The CBF response to changes in CO2 tension can be reliably estimated from noninvasive measurement of Petco2.

Download Full-text

Faculty Opinions recommendation of Alterations in cerebral blood flow and cerebrovascular reactivity during 14 days at 5050 m.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.8302956.8739054 ◽

2011 ◽

Author(s):

James Duffin

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Cerebrovascular Reactivity

Download Full-text

Transcranial Doppler Evaluation of the Cerebral Vasculature in Women Patients who Have Migraine with Aura

Pain Medicine ◽

10.1093/pm/pnaa292 ◽

2020 ◽

Vol 21 (11) ◽

pp. 3012-3017

Author(s):

Igor Petrušić ◽

Ana Podgorac ◽

Aleksandra Radojičić ◽

Jasna Zidverc-Trajković

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Migraine With Aura ◽

Transcranial Doppler ◽

Cerebral Blood Flow Velocity ◽

Cerebral Arteries ◽

Transcranial Doppler Sonography ◽

Cerebrovascular Reactivity ◽

Breath Holding ◽

Left And Right

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.

Download Full-text

Effects of smoking on regional cerebral blood flow in cerebral vascular disease patients and normal subjects.

The Tohoku Journal of Experimental Medicine ◽

10.1620/tjem.151.261 ◽

1987 ◽

Vol 151 (3) ◽

pp. 261-268 ◽

Cited By ~ 5

Author(s):

KAZUO KUBOTA ◽

TATSUO YAMAGUCHI ◽

TAKEHIKO FUJIWARA ◽

TAIJU MATSUZAWA

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Vascular Disease ◽

Regional Cerebral Blood Flow ◽

Normal Subjects ◽

Regional Cerebral Blood ◽

Cerebral Vascular Disease ◽

Cerebral Vascular

Download Full-text

Gas exchange in dogs in the prone and supine positions

Journal of Applied Physiology ◽

10.1152/jappl.1992.72.6.2292 ◽

1992 ◽

Vol 72 (6) ◽

pp. 2292-2297 ◽

Cited By ~ 49

Author(s):

K. C. Beck ◽

J. Vettermann ◽

K. Rehder

Keyword(s):

Blood Flow ◽

Gas Exchange ◽

Prone Position ◽

Pulmonary Blood Flow ◽

Random Order ◽

Arterial Pco2 ◽

Supine Posture ◽

Pulmonary Shunting ◽

The Difference ◽

Arterial Po2

To determine the cause of the difference in gas exchange between the prone and supine postures in dogs, gas exchange was assessed by the multiple inert gas elimination technique (MIGET) and distribution of pulmonary blood flow was determined using radioactively labeled microspheres in seven anesthetized paralyzed dogs. Each animal was studied in the prone and supine positions in random order while tidal volume and respiratory frequency were kept constant with mechanical ventilation. Mean arterial PO2 was significantly lower (P less than 0.01) in the supine [96 +/- 10 (SD) Torr] than in the prone (107 +/- 6 Torr) position, whereas arterial PCO2 was constant (38 Torr). The distribution of blood flow (Q) vs. ventilation-to-perfusion ratio obtained from MIGET was significantly wider (P less than 0.01) in the supine [ln SD(Q) = 0.75 +/- 0.26] than in the prone position [ln SD (Q) = 0.34 +/- 0.05]. Right-to-left pulmonary shunting was not significantly altered. The distribution of microspheres was more heterogeneous in the supine than in the prone position. The larger heterogeneity was due in part to dorsal-to-ventral gradients in Q in the supine position that were not present in the prone position (P less than 0.01). The decreased efficiency of oxygenation in the supine posture is caused by an increased ventilation-to-perfusion mismatch that accompanies an increase in the heterogeneity of Q distribution.

Download Full-text

Comparison of the Effects of Intravenous Papaverine Hydrochloride and Oral Pavabid HP Capsulets on Regional Cerebral Blood Flow in Normal Individuals

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1983.70 ◽

1983 ◽

Vol 3 (4) ◽

pp. 442-447 ◽

Cited By ~ 5

Author(s):

Lawrence C. McHenry ◽

David A. Stump ◽

George Howard ◽

Thomas T. Novack ◽

Don H. Bivins ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Regional Cerebral Blood Flow ◽

Normal Subjects ◽

Normal Male ◽

Regional Cerebral Blood ◽

Normal Individuals ◽

Left And Right ◽

Male Subjects ◽

Papaverine Hydrochloride

A single-blind study was conducted in 13 right-handed normal male subjects to compare the effects of oral and i.v. papaverine on regional cerebral blood flow (rCBF). Six xenon-133 inhalation rCBF measurements were performed on each subject; three tests—baseline, placebo, and drug evaluations—were carried out on each of two separate days. The oral and i.v. drugs were randomized for first-day administration. rCBF, measured as flow gray (FG), increased significantly (p ≤ 0.001) from baseline with both drug forms. Increases of 10.53% and 13.94% (left and right hemispheres, respectively) were demonstrated 90 min after a single 600-mg dose of oral papaverine. Increases of 5.09% and 8.69%, respectively, were recorded immediately after a single 100-mg dose of i. v. papaverine. FG also increased significantly (p ≤ 0.001) for both drug forms when compared to that of placebo. Placebo produced only a slight increase (not significant) with both the oral and i.v. groups. The data show that both oral and i.v. papaverine are equally effective in increasing rCBF in normal subjects.

Download Full-text

Effects of Aging and Hypertension on Cerebral Blood Flow and Autoregulation in Normal Subjects and CVD Patients

Aging 2000: Our Health Care Destiny ◽

10.1007/978-1-4612-5058-6_15 ◽

1985 ◽

pp. 185-194

Author(s):

Yukito Shinohara

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Normal Subjects ◽

Effects Of Aging

Download Full-text

Higher Aortic Stiffness Is Related to Lower Cerebral Blood Flow and Preserved Cerebrovascular Reactivity in Older Adults

Circulation ◽

10.1161/circulationaha.118.032410 ◽

2018 ◽

Vol 138 (18) ◽

pp. 1951-1962 ◽

Cited By ~ 37

Author(s):

Angela L. Jefferson ◽

Francis E. Cambronero ◽

Dandan Liu ◽

Elizabeth E. Moore ◽

Jacquelyn E. Neal ◽

...

Keyword(s):

Older Adults ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Aortic Stiffness ◽

Cerebrovascular Reactivity

Download Full-text

Effects of GV14 Acupuncture on Cerebral Blood Flow Velocity in the Basilar and Middle Cerebral Arteries and CO2 Reactivity during Hypercapnia in Normal Individuals

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/9319413 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Hyun Ku Lee ◽

Sang-Kwan Moon ◽

Chul Jin ◽

Seung-Yeon Cho ◽

Seong-Uk Park ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Flow Velocity ◽

Blood Flow Velocity ◽

Cerebral Arteries ◽

Transcranial Doppler Sonography ◽

Cerebrovascular Reactivity ◽

Acupuncture Points ◽

Co2 Reactivity ◽

Middle Cerebral Arteries

The Governing Vessel 14 (GV14) (Dazhui) is one of the acupuncture points referred to as “seven acupoints for stroke.” Nevertheless, there is a scarcity of research on the effects of acupuncture treatment at GV14. This study investigated the effects of acupuncture at GV14 on cerebral blood flow (CBF), especially that in the basilar artery (BA) and the middle cerebral arteries (MCA). Sixteen healthy men aged 20 to 29 years were enrolled in this study. CBF velocity and cerebrovascular reactivity (CVR) were measured using transcranial Doppler sonography (TCD). The following were assessed: closed circuit rebreathing- (CCR-) induced carbon dioxide (CO2) reactivity, modified blood flow velocity at 40 mmHg (CV40) on BA and MCAs, blood pressure (BP), and heart rate (HR). Observed results were obtained after comparison with the baseline evaluation. Statistically significant elevations in CO2 reactivity were recorded in the BA (3.28 to 4.70, p < 0.001 ) and MCAs (right: 3.81 to 5.25, p = 0.001 ; left: 3.84 to 5.12, p = 0.005 ) after acupuncture at GV14. The CV40 increased statistically significantly only in the BA (45.49 to 50.41, p = 0.003 ). No change was observed in BP (106.83 to 107.08 (mmHg), p = 0.335 ) and HR (77 to 75 (bpm), p = 0.431 ). Acupuncture at GV14 improved CBF velocity. These results could be explained by the regulation of endothelium-dependent vessel dilation effected by acupuncture. This trial is registered with Korean Clinical Trial Registry (http://cris.nih.go.kr; registration number: KCT0004787).

Download Full-text