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Erkoç Ataoğlu E, Batur Çağlayan H, Nazliel B, Çinar M, Akyol Gürses A, Moraloğlu Tekin Ö. Middle Cerebral Artery Blood Flow Velocity During Normal Pregnancy. Neurologist 2024; 29:45-49. [PMID: 37607532 DOI: 10.1097/nrl.0000000000000523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
BACKGROUND The present study aimed to evaluate resting middle cerebral artery (MCA) blood flow velocities using transcranial Doppler ultrasound (TCD) in healthy women at different stages of pregnancy, and to compare these velocities with those of normal controls. METHODS A total of 105 healthy normotensive pregnant women and 25 non-pregnant healthy controls were included in the study. We formed 3 groups according to gestational age: first trimester (7 to 13 wk pregnant), second trimester (14 to 28 wk pregnant), and third trimester (29 to 42 wk pregnant). Age, body mass index, heart rate, arterial blood pressure, and hematological data were recorded and TCD was performed on the subjects. Regarding TCD, we evaluated the mean cerebral blood flow velocity, the peak systolic velocity, the end-diastolic flow velocity, S/D ratio, the pulsatility Index (PI) and the resistance Index (RI). RESULTS The MCA mean blood flow velocities differed significantly among the groups ( P <0.001) and were higher in the controls than those of the first trimester, second trimester, and third trimester groups ( P <0.01, P <0.001, P <0.001 respectively). The MCA mean and peak blood flow velocities, and the PI and RI decreased significantly with advancing gestation. CONCLUSIONS TCD is a noninvasive and non-toxic method of monitoring the adaptation of the maternal cerebral blood flow in pregnancy. The progressive decreases in the MCA mean and peak blood flow velocities, PI, and RI during gestation may be the result of chemical and neuronal factors. This study supports the need for additional studies using TCD to establish normative cerebral blood flow volumes throughout pregnancy.
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Affiliation(s)
| | | | - Bijen Nazliel
- Department of Neurology, Faculty of Medicine, Gazi University
| | - Mehmet Çinar
- Department of Obstetrics and Gynecology, University of Health Sciences, Ankara, Turkey
| | | | - Özlem Moraloğlu Tekin
- Department of Obstetrics and Gynecology, University of Health Sciences, Ankara, Turkey
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Zadek F, Giudici G, Ferraris Fusarini C, Ambrosini MT, di Modugno A, Scaravilli V, Zanella A, Fumagalli R, Stocchetti N, Calderini E, Langer T. Cerebrospinal fluid and arterial acid-base equilibria in spontaneously breathing third-trimester pregnant women. Br J Anaesth 2022; 129:726-733. [PMID: 36096944 PMCID: PMC9642833 DOI: 10.1016/j.bja.2022.07.048] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 06/17/2022] [Accepted: 07/10/2022] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Acid-base status in full-term pregnant women is characterised by hypocapnic alkalosis. Whether this respiratory alkalosis is primary or consequent to changes in CSF electrolytes is not clear. METHODS We enrolled third-trimester pregnant women (pregnant group) and healthy, non-pregnant women of childbearing age (controls) undergoing spinal anaesthesia for Caesarean delivery and elective surgery, respectively. Electrolytes, strong ion difference (SID), partial pressure of carbon dioxide ( [Formula: see text] ), and pH were measured in simultaneously collected CSF and arterial blood samples. RESULTS All pregnant women (20) were hypocapnic, whilst only four (30%) of the controls (13) had an arterial [Formula: see text] <4.7 kPa (P<0.001). The incidence of hypocapnic alkalosis was higher in the pregnant group (65% vs 8%; P=0.001). The CSF-to-plasma Pco2 difference was significantly higher in pregnant women (1.5 [0.3] vs 1.0 [0.4] kPa; P<0.001), mainly because of a decrease in arterial Pco2 (3.9 [0.3] vs 4.9 [0.5] kPa; P<0.001). Similarly, the CSF-to-plasma difference in SID was less negative in pregnant women (-7.8 [1.4] vs -11.4 [2.3] mM; P<0.001), mainly because of a decreased arterial SID (31.5 [1.2] vs 36.1 [1.9] mM; P<0.001). The major determinant of the reduced plasma SID of pregnant women was a relative increase in plasma chloride compared with sodium. CONCLUSIONS Primary hypocapnic alkalosis characterises third-trimester pregnant women leading to chronic acid-base adaptations of CSF and plasma. The compensatory SID reduction, mainly sustained by an increase in chloride concentration, is more pronounced in plasma than in CSF, as the decrease in Pco2 is more marked in this compartment. CLINICAL TRIAL REGISTRATION NCT03496311.
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Affiliation(s)
- Francesco Zadek
- Department of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy
| | - Giorgio Giudici
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | | | - Maria T. Ambrosini
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Adriana di Modugno
- Central Laboratory, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Vittorio Scaravilli
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy,Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Alberto Zanella
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy,Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Roberto Fumagalli
- Department of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy,Department of Anesthesia and Intensive Care Medicine, Niguarda Ca’ Granda, Milan, Italy
| | - Nino Stocchetti
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy,Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Edoardo Calderini
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Thomas Langer
- Department of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy,Department of Anesthesia and Intensive Care Medicine, Niguarda Ca’ Granda, Milan, Italy,Corresponding author.
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Brislane Á, Steinback CD, Davenport MH. The Nine Month Stress Test: Pregnancy and Exercise - Similarities and Interactions. Can J Cardiol 2021; 37:2014-2025. [PMID: 34534622 DOI: 10.1016/j.cjca.2021.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 08/18/2021] [Accepted: 09/03/2021] [Indexed: 11/29/2022] Open
Abstract
Of all physiological systems, the cardiovascular system takes on the most profound adaptation in pregnancy to support fetal growth and development. The adaptations that arise are systemic and involve structural and functional changes that can be observed at the cerebral, central, peripheral, and microvascular beds. This includes, although is not limited to increased heart rate, stroke volume and cardiac output with negligible change to blood pressure, reductions in vascular resistance and cerebral blood flow velocity, systemic artery enlargement, enhanced endothelial function. All of this takes place to accommodate blood volume expansion and ensure adequate fetal and maternal oxygen delivery. In some instances, the demand placed on the vasculature can manifest as cardiovascular maladaptation and thus, cardiovascular complications can arise. Exercise is recommended in pregnancy because of its powerful ability to reduce the incidence and severity of cardiovascular complications in pregnancy. However, the mechanism by which it acts is poorly understood. The first aim of this review is to describe the systemic adaptations that take place in pregnancy. Secondly, this review aims to describe the influence of exercise on these systemic adaptations. It is anticipated that this review can comprehensively capture the extent of knowledge in this area while identifying areas that warrant further investigation.
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Affiliation(s)
- Áine Brislane
- Program for Pregnancy & Postpartum Health, Neurovascular Health Lab, Faculty of Kinesiology, Sport, and Recreation, Women and Children's Health Research Institute, Alberta Diabetes Institute, University of Alberta, Alberta, Canada
| | - Craig D Steinback
- Program for Pregnancy & Postpartum Health, Neurovascular Health Lab, Faculty of Kinesiology, Sport, and Recreation, Women and Children's Health Research Institute, Alberta Diabetes Institute, University of Alberta, Alberta, Canada
| | - Margie H Davenport
- Program for Pregnancy & Postpartum Health, Neurovascular Health Lab, Faculty of Kinesiology, Sport, and Recreation, Women and Children's Health Research Institute, Alberta Diabetes Institute, University of Alberta, Alberta, Canada.
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Skinner BD, Davies RJ, Weaver SR, Cable NT, Lucas SJE, Lucas RAI. A Systematic Review and Meta-Analysis Examining Whether Changing Ovarian Sex Steroid Hormone Levels Influence Cerebrovascular Function. Front Physiol 2021; 12:687591. [PMID: 34220552 PMCID: PMC8248489 DOI: 10.3389/fphys.2021.687591] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 05/21/2021] [Indexed: 01/14/2023] Open
Abstract
Sex differences in cerebrovascular disease rates indicate a possible role for ovarian sex steroid hormones in cerebrovascular function. To synthesise and identify knowledge gaps, a systematic review and meta-analysis was conducted to assess how ovarian sex steroid hormone changes across the lifespan affect cerebrovascular function in women. Three databases (EMBASE, MEDLINE and Web of Science) were systematically searched for studies on adult cerebrovascular function and ovarian sex steroid hormones. Forty-five studies met pre-defined inclusion criteria. Studied hormone groups included hormone replacement therapy (HRT; n = 17), pregnancy (n = 12), menstrual cycle (n = 7), menopause (n = 5), oral contraception (n = 2), and ovarian hyperstimulation (n = 2). Outcome measures included pulsatility index (PI), cerebral blood flow/velocity (CBF), resistance index (RI), cerebral autoregulation, and cerebrovascular reactivity. Meta-analysis was carried out on HRT studies. PI significantly decreased [−0.05, 95% CI: (−0.10, −0.01); p = 0.01] in post-menopausal women undergoing HRT compared to post-menopausal women who were not, though there was considerable heterogeneity (I2 = 96.8%). No effects of HRT were seen in CBF (p = 0.24) or RI (p = 0.77). This review indicates that HRT improves PI in post-menopausal women. However, there remains insufficient evidence to determine how changing ovarian sex steroid hormone levels affects cerebrovascular function in women during other hormonal phases (e.g., pregnancy, oral contraception).
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Affiliation(s)
- Bethany D Skinner
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom.,Centre for Human Brain Health, University of Birmingham, Birmingham, United Kingdom
| | - Rebecca J Davies
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Samuel R Weaver
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom.,Centre for Human Brain Health, University of Birmingham, Birmingham, United Kingdom
| | - N Tim Cable
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Samuel J E Lucas
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom.,Centre for Human Brain Health, University of Birmingham, Birmingham, United Kingdom
| | - Rebekah A I Lucas
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom
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Gokina NI, Fairchild RI, Prakash K, DeLance NM, Bonney EA. Deficiency in CD4 T Cells Leads to Enhanced Postpartum Internal Carotid Artery Vasoconstriction in Mice: The Role of Nitric Oxide. Front Physiol 2021; 12:686429. [PMID: 34220551 PMCID: PMC8242360 DOI: 10.3389/fphys.2021.686429] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 05/10/2021] [Indexed: 11/13/2022] Open
Abstract
The risk of postpartum (PP) stroke is increased in complicated pregnancies. Deficiency in CD4 T cell subsets is associated with preeclampsia and may contribute to PP vascular disease, including internal carotid artery (ICA) stenosis and stroke. We hypothesized that CD4 T cell deficiency in pregnancy would result in ICA dysregulation, including enhanced ICA vasoconstriction. We characterized the function, mechanical behavior, and structure of ICAs from C57BL/6 (WT) and CD4 deficient (CD4KO) mice, and assessed the role of NO in the control of ICA function at pre-conception and PP. WT and CD4KO mice were housed under pathogen-free conditions, mated to same-strain males, and allowed to litter or left virgin. At 3 days or 4 weeks PP, mice were euthanized. The responses to phenylephrine (PE), high K+ and acetylcholine (ACh) were assessed in pressurized ICAs before and after NOS inhibition. Passive lumen diameters were measured at 3–140 mmHg. eNOS and iNOS expression as well as the presence of T cells were evaluated by immunohistochemistry. Constriction of WT ICAs to PE was not modified PP. In contrast, responses to PE were significantly increased in ICAs from PP as compared to virgin CD4KO mice. Constriction to high K+ was not enhanced PP. ICAs from WT and CD4KO mice were equally sensitive to ACh with a significant rightward shift of dose-response curves after L-NNA treatment. NOS inhibition enhanced PE constriction of ICAs from WT virgin and PP mice. Although a similar effect was detected in ICAs of virgin CD4KO mice, no such changes were observed in vessels from PP CD4KO mice. Passive arterial distensibility at physiological levels of pressure was not modified at PP. ICA diameters were significantly increased in PP with no change in vascular wall thickness. Comparison of eNOS expression in virgin, 3 days and 4 weeks PP revealed a reduced expression in ICA from CD4 KO vs. WT PP vessels which reached significance at 4 weeks PP. iNos expression was similar and decreased over the PP period in vessels from WT and CD4KO mice. Dysregulation of the CD4 T cell population in pregnancy may make ICA vulnerable to vasospasm due to decreased NO-dependent control of ICA constriction. This may lead to cerebral hypoperfusion and increase the risk of maternal PP stroke.
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Affiliation(s)
- Natalia I Gokina
- Department of Obstetrics, Gynecology and Reproductive Sciences, Larner College of Medicine, The University of Vermont, Burlington, VT, United States
| | - Rebecca I Fairchild
- Department of Obstetrics, Gynecology and Reproductive Sciences, Larner College of Medicine, The University of Vermont, Burlington, VT, United States
| | - Kirtika Prakash
- Department of Obstetrics, Gynecology and Reproductive Sciences, Larner College of Medicine, The University of Vermont, Burlington, VT, United States
| | - Nicole M DeLance
- Microscopy Imaging Center, Larner College of Medicine, The University of Vermont, Burlington, VT, United States
| | - Elizabeth A Bonney
- Department of Obstetrics, Gynecology and Reproductive Sciences, Larner College of Medicine, The University of Vermont, Burlington, VT, United States
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Maternal microvascular dysfunction during preeclamptic pregnancy. Clin Sci (Lond) 2021; 135:1083-1101. [PMID: 33960392 DOI: 10.1042/cs20200894] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 04/19/2021] [Accepted: 04/21/2021] [Indexed: 12/15/2022]
Abstract
Preeclampsia is a hypertensive disorder of pregnancy effecting ∼5-8% of pregnancies in the United States, and ∼8 million pregnancies worldwide. Preeclampsia is clinically diagnosed after the 20th week of gestation and is characterized by new onset hypertension accompanied by proteinuria and/or thrombocytopenia, renal insufficiency, impaired liver function, pulmonary edema, or cerebral or visual symptoms. This broad definition emphasizes the heterogeneity of the clinical presentation of preeclampsia, but also underscores the role of the microvascular beds, specifically the renal, cerebral, and hepatic circulations, in the pathophysiology of the disease. While the diagnostic criteria for preeclampsia relies on the development of de novo hypertension and accompanying clinical symptoms after 20-week gestation, it is likely that subclinical dysfunction of the maternal microvascular beds occurs in parallel and may even precede the development of overt cardiovascular symptoms in these women. However, little is known about the physiology of the non-reproductive maternal microvascular beds during preeclampsia, and the mechanism(s) mediating microvascular dysfunction during preeclamptic pregnancy are largely unexplored in humans despite their integral role in the pathophysiology of the disease. Therefore, the purpose of this review is to provide a summary of the existing literature on maternal microvascular dysfunction during preeclamptic pregnancy by reviewing the functional evidence in humans, highlighting potential mechanisms, and providing recommendations for future work in this area.
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Batur Caglayan HZ, Nazliel B, Cinar M, Ataoglu E, Moraloglu O, Irkec C. Assessment of maternal cerebral blood flow velocity by transcranial Doppler ultrasound before delivery and in the early postpartum period. J Matern Fetal Neonatal Med 2017; 32:584-589. [PMID: 29034765 DOI: 10.1080/14767058.2017.1387529] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVE This prospective observational study aimed to identify the effects of labor on cerebral hemodynamics by measuring the middle cerebral artery (MCA) blood flow velocity by transcranial Doppler ultrasound (TCD), and the related factors just before delivery and within the 24 h after delivery. METHODS The study included 35 healthy pregnant women with a gestational age of >37 weeks who were in labor and a control group including healthy, age-matched, nonpregnant women (n = 24). Demographic characteristics and significant clinical information of pregnant women were recorded. The MCA blood flow velocity was assessed by TCD just before and within 24 h after delivery. The parameters assessed by TCD were mean cerebral blood flow velocity (MCBFV), peak systolic velocity (PSV), pulsatility index (PI), resistance index (RI), and systolic/diastolic ratio. RESULTS There was no significant difference between the pregnant and nonpregnant women regarding age (27 ± 5 years versus 28 ± 7 years; p = .751). The MCBFV, PSV, PI, and RI showed a significant increase within the 24 h after delivery as compared with those before delivery. Comparison of the pregnant women with the control group in terms of the values of all parameters related to the MCA blood flow velocity revealed that the values that were significantly low before delivery reached to the level of the control group after delivery Conclusion: The findings of this study demonstrated that the blood flow velocity of the MCA decreased during the late pregnancy period and increased in the early postpartum period to the level similar to that of the nonpregnant group.
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Affiliation(s)
| | - Bijen Nazliel
- a Department of Neurology , Gazi University Faculty of Medicine , Ankara , Turkey
| | - Mehmet Cinar
- b Department of Obstetrics and Gynecology , Zekai Tahir Burak Women's Health Education and Research Hospital , Ankara , Turkey
| | - Esra Ataoglu
- c Department of Neurology , Zekai Tahir Burak Women's Health Education and Research Hospital , Ankara , Turkey
| | - Ozlem Moraloglu
- b Department of Obstetrics and Gynecology , Zekai Tahir Burak Women's Health Education and Research Hospital , Ankara , Turkey
| | - Ceyla Irkec
- a Department of Neurology , Gazi University Faculty of Medicine , Ankara , Turkey
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van Veen TR, Haeri S, Sangi-Haghpeykar H, Belfort MA. Changes in maternal posterior and anterior cerebral artery flow velocity during pregnancy and postpartum--a longitudinal study. JOURNAL OF CLINICAL ULTRASOUND : JCU 2013; 41:532-537. [PMID: 23996414 DOI: 10.1002/jcu.22091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 06/04/2013] [Accepted: 07/17/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND To evaluate the normal range of blood flow velocity in the maternal anterior (ACA) and posterior cerebral arteries (PCA) along the normal pregnancy and postpartum period. METHODS Transcranial Doppler ultrasound was used to measure the systolic, diastolic, and mean blood velocities in the ACA and PCA during normal gestation. The resistance and pulsatility indices were calculated. Data were analyzed using multilevel modeling, incorporating random effects models, to construct mean and percentile curves. RESULTS We performed 355 measurements on 59 patients, which showed that systolic and mean velocity in the ACA decreased, whereas diastolic velocity increased in the PCA during normal pregnancy. Resistance and pulsatility indices in both vessels increased to a maximum in the second trimester, decreased during the third trimester, and increased during the postpartum period. CONCLUSIONS This study provides normative data for ACA and PCA velocity and indices during pregnancy and postpartum, demonstrating changes in velocity that suggest a shift of cerebral blood flow from the anterior to the posterior cerebral circulation.
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Affiliation(s)
- Teelkien R van Veen
- Department of Obstetrics and Gynecology, University Medical Center Groningen, Groningen, The Netherlands; Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
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Silva FCD, Sá RAMD, Velarde LGC, Suarez B, Ville Y. Doppler sonography of maternal cerebral arteries in pregnancy: side-to-side differences. Gynecol Obstet Invest 2010; 72:25-31. [PMID: 21160166 DOI: 10.1159/000322218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 10/14/2010] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS To study side-to-side differences in blood flow of the common and internal carotid arteries, and the vertebral arteries (VAs) in women with uncomplicated pregnancies as a first step to build a reference values chart. METHODS A total of 155 healthy pregnant women between 20 and 40 weeks' gestation were included. Doppler sonography of the common and internal carotid arteries and VAs was performed on both sides. Parameters measured included diameter, peak systolic velocity, systolic-diastolic ratio, end-diastolic velocity, pulsatility index and resistance index. Statistical analysis was performed using the S-Plus 8.0 program. Normality was determined using the Kolmogorov-Smirnov test. Differences between sides were tested using Student's paired t test, association using linear correlation, and agreement using the Bland-Altman method. RESULTS Mean values were equal between sides for all parameters with the exception of the end-diastolic velocity in the VAs. The association and agreement between the measurements taken from the right and left sides were poor. Bland-Altman plots also indicated low agreement between sides. All parameters showed significant right-to-left differences. CONCLUSION Despite the equality between means, right and left flows through the vessels studied differed as there was poor association and agreement.
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Affiliation(s)
- Fernanda Campos da Silva
- Clínica Perinatal, Bonsucesso General Hospital, Fluminense Federal University,Av. Abelardo Bueno 201, Barra, Rio de Janeiro, Brazil.
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Brodie FG, Panerai RB, Foster S, Evans DH, Robinson TG. Long-term changes in dynamic cerebral autoregulation: a 10 years follow up study. Clin Physiol Funct Imaging 2009; 29:366-71. [DOI: 10.1111/j.1475-097x.2009.00880.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Jensen D, Duffin J, Lam YM, Webb KA, Simpson JA, Davies GA, Wolfe LA, O’Donnell DE. Physiological mechanisms of hyperventilation during human pregnancy. Respir Physiol Neurobiol 2008; 161:76-86. [DOI: 10.1016/j.resp.2008.01.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Revised: 12/17/2007] [Accepted: 01/07/2008] [Indexed: 11/27/2022]
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Immink RV, Secher NH, van Lieshout JJ. Cerebral Autoregulation and CO2 Responsiveness of the Brain. Am J Physiol Heart Circ Physiol 2006; 291:H2018; author reply H2019. [PMID: 16648186 DOI: 10.1152/ajpheart.00390.2006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Bergersen TK, Hartgill T, Pirhonen J. REPLY. Am J Physiol Heart Circ Physiol 2006. [DOI: 10.1152/ajpheart.00415.2006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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