keyword
MENU ▼
Read by QxMD icon Read
search

Cerebral autoregulation

keyword
https://www.readbyqxmd.com/read/28333037/cerebral-hemodynamic-with-intra-aortic-balloon-pump-business-as-usual
#1
Juliana Caldas, Ronney B Panerai, Edson Bor-Seng-Shu, Juliano Almeida, Graziela Ferreira, Ligia Cunha, Ricardo Nogueira, Marcelo Oliveira, Fabio Jatene, Thompson Robinson, Ludhmila Hajjar
Intra-aortic balloon pump (IABP) is commonly used as mechanical support after cardiac surgery or cardiac shock. Although its benefits for cardiac function have been well documented, its effects on cerebral circulation are still controversial. We hypothesized that transfer function analysis (TFA) and continuous estimates of dynamic cerebral autoregulation (CA) provide consistent results in the assessment of cerebral autoregulation in patients with IABP. Continuous recordings of blood pressure (BP, intra-arterial line), end-tidal CO2, heart rate and cerebral blood flow velocity (CBFV, transcranial Doppler) were obtained i) 5 minutes with IABP ratio 1:3, ii) 5 minutes, starting 1 minute with the IABP-ON, and continuing for another 4 minutes without pump assistance (IABP-OFF)...
March 23, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28325005/dynamic-modeling-of-apnea-induced-concurrent-variations-in-arterial-blood-pressure-and-cerebral-blood-flow-velocity
#2
Raichel Alex, Rong Zhang, Donald E Watenpaugh, Khosrow Behbehani
Obstructive Sleep Apnea (OSA) is characterized by partial (hypopnea) or complete cessation (apnea) of airflow to the lungs during sleep. It has been previously reported that apnea episodes lead to significant rise in instantaneous blood pressure concomitant with a rise in cerebral blood flow velocity, indicating loss of cerebral autoregulation during the episodes. In this study, we have used Auto Regressive Moving Average model (ARMA (na, nb, nk)) to quantify OSA induced dynamic changes in cerebral blood flow velocity (CBFV) with beat to beat blood pressure (BP) as an input...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28316994/multiple-factors-involved-in-the-pathogenesis-of-white-matter-lesions
#3
REVIEW
Jing Lin, Dilong Wang, Linfang Lan, Yuhua Fan
White matter lesions (WMLs), also known as leukoaraiosis (LA) or white matter hyperintensities (WMHs), are characterized mainly by hyperintensities on T2-weighted or fluid-attenuated inversion recovery (FLAIR) images. With the aging of the population and the development of imaging technology, the morbidity and diagnostic rates of WMLs are increasing annually. WMLs are not a benign process. They clinically manifest as cognitive decline and the subsequent development of dementia. Although WMLs are important, their pathogenesis is still unclear...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28306631/thermoregulate-autoregulate-and-ventilate-brain-directed-critical-care-for-pediatric-cardiac-arrest
#4
Jonathan E Kurz, Craig M Smith, Mark S Wainwright
PURPOSE OF REVIEW: Cardiac arrest in childhood is associated with a high risk for mortality and poor long-term functional outcome. This review discusses the current evidence for neuroprotective therapies and goals for postarrest care in the context of the pathophysiology of hypoxic-ischemic injury, modalities for neurologic prognostication in these children and potential future monitoring paradigms for maximizing cerebral perfusion in the postarrest period. RECENT FINDINGS: The recent publication of the in-hospital and out-of-hospital Therapeutic Hypothermia After Cardiac Arrest trials demonstrated a lack of statistically significant benefit for the use of postarrest therapeutic hypothermia...
March 16, 2017: Current Opinion in Pediatrics
https://www.readbyqxmd.com/read/28302943/cerebral-hemodynamics-and-metabolism-during-cardiac-arrest-and-cardiopulmonary-resuscitation-using-hyperspectral-near-infrared-spectroscopy
#5
Reyhaneh Nosrati, Steve Lin, Andrew Ramadeen, Dena Monjazebi, Paul Dorian, Vladislav Toronov
BACKGROUND: Maintaining cerebral oxygen delivery and metabolism during cardiac arrest (CA) through resuscitation is essential to improve the survival rate while avoiding brain injury. The effect of CA and cardiopulmonary resuscitation (CPR) on cerebral and muscle oxygen delivery and metabolism is not clearly quantified.Methods and Results:A novel hyperspectral near-infrared spectroscopy (hNIRS) technique was developed and evaluated to measure cerebral oxygen delivery and aerobic metabolism during ventricular fibrillation (VF) CA and CPR in 14 pigs...
March 10, 2017: Circulation Journal: Official Journal of the Japanese Circulation Society
https://www.readbyqxmd.com/read/28302914/new-insights-into-mechanisms-of-small-vessel-disease-stroke-from-genetics
#6
REVIEW
Rhea Tan, Matthew Traylor, Loes Rutten-Jacobs, Hugh Markus
Cerebral small vessel disease (SVD) is a common cause of lacunar strokes, vascular cognitive impairment (VCI) and vascular dementia. SVD is thought to result in reduced cerebral blood flow, impaired cerebral autoregulation and increased blood-brain barrier (BBB) permeability. However, the molecular mechanisms underlying SVD are incompletely understood. Recent studies in monogenic forms of SVD, such as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), and 'sporadic' SVD have shed light on possible disease mechanisms in SVD...
April 1, 2017: Clinical Science (1979-)
https://www.readbyqxmd.com/read/28299725/defining-the-relationship-between-hypertension-cognitive-decline-and-dementia-a-review
#7
REVIEW
Keenan A Walker, Melinda C Power, Rebecca F Gottesman
Hypertension is a highly prevalent condition which has been established as a risk factor for cardiovascular and cerebrovascular disease. Although the understanding of the relationship between cardiocirculatory dysfunction and brain health has improved significantly over the last several decades, it is still unclear whether hypertension constitutes a potentially treatable risk factor for cognitive decline and dementia. While it is clear that hypertension can affect brain structure and function, recent findings suggest that the associations between blood pressure and brain health are complex and, in many cases, dependent on factors such as age, hypertension chronicity, and antihypertensive medication use...
March 2017: Current Hypertension Reports
https://www.readbyqxmd.com/read/28291094/predictors-of-outcome-with-cerebral-autoregulation-monitoring-a-systematic-review-and-meta-analysis
#8
Lucia Rivera-Lara, Andres Zorrilla-Vaca, Romer Geocadin, Wendy Ziai, Ryan Healy, Richard Thompson, Peter Smielewski, Marek Czosnyka, Charles W Hogue
OBJECTIVE: To compare cerebral autoregulation indices as predictors of patient outcome and their dependence on duration of monitoring. DATA SOURCES: Systematic literature search and meta-analysis using PubMed, EMBASE, and the Cochrane Library from January 1990 to October 2015. STUDY SELECTION: We chose articles that assessed the association between cerebral autoregulation indices and dichotomized or continuous outcomes reported as standardized mean differences or correlation coefficients (R), respectively...
April 2017: Critical Care Medicine
https://www.readbyqxmd.com/read/28270412/relationship-between-hypotension-and-cerebral-ischemia-during-hemodialysis
#9
Clare MacEwen, Sheera Sutherland, Jonathan Daly, Christopher Pugh, Lionel Tarassenko
The relationship between BP and downstream ischemia during hemodialysis has not been characterized. We studied the dynamic relationship between BP, real-time symptoms, and cerebral oxygenation during hemodialysis, using continuous BP and cerebral oxygenation measurements prospectively gathered from 635 real-world hemodialysis sessions in 58 prevalent patients. We examined the relationship between BP and cerebral ischemia (relative drop in cerebral saturation >15%) and explored the lower limit of cerebral autoregulation at patient and population levels...
March 7, 2017: Journal of the American Society of Nephrology: JASN
https://www.readbyqxmd.com/read/28268423/dynamic-cerebral-autoregulation-in-young-athletes-following-concussion
#10
Kyriaki Kostoglou, Alexander D Wright, Jonathan D Smirl, Kelsey Bryk, Paul van Donkelaar, Georgios D Mitsis
The purpose of this study was to examine cerebral autoregulation (CA) in young athletes experiencing concussion. The subjects were monitored and repeatedly tested 72 hours, 2 weeks and 1 month post-injury. Mean arterial blood pressure (MABP), end-tidal partial pressure of carbon dioxide (PETCO2) and cerebral blood flow velocity (CBFV) in the middle and posterior cerebral arteries were monitored during mental activation paradigms. In order to characterize CA we employed autoregressive models with exogenous inputs (ARX) and impulse response models based on the Laguerre expansion technique (LET)...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28268070/post-carotid-endarterectomy-hypertension-part-1-association-with-pre-operative-clinical-imaging-and-physiological-parameters
#11
J E Newman, M J Bown, R D Sayers, J P Thompson, T G Robinson, B Williams, R Panerai, P Lacy, A R Naylor
OBJECTIVE/BACKGROUND: Post-endarterectomy hypertension (PEH) is a well recognised, but poorly understood, phenomenon after carotid endarterectomy (CEA) that is associated with post-operative intracranial haemorrhage, hyperperfusion syndrome, and cardiac complications. The aim of the current study was to identify pre-operative clinical, imaging, and physiological parameters associated with PEH. METHODS: In total, 106 CEA patients undergoing CEA under general anaesthesia underwent pre-operative evaluation of 24 hour ambulatory arterial blood pressure (BP), baroreceptor sensitivity, cerebral autoregulation, and transcranial Doppler measurement of cerebral blood flow velocity (CBFv) and pulsatility index...
March 3, 2017: European Journal of Vascular and Endovascular Surgery
https://www.readbyqxmd.com/read/28262564/is-dynamic-cerebral-autoregulation-bilaterally-impaired-after-unilateral-acute-ischemic-stroke
#12
Li Xiong, Ge Tian, Wenhua Lin, Wei Wang, Lijuan Wang, Thomas Leung, Vincent Mok, Jia Liu, Xiangyan Chen, Ka Sing Wong
OBJECTIVE: Whether dynamic cerebral autoregulation (dCA) is impaired focally in the affected hemisphere or bilaterally in both the affected and nonaffected hemispheres after ischemic stroke remains controversial. We therefore investigated the pattern of dCA in acute ischemic stroke patients with different subtypes. METHODS: Sixty acute ischemic stroke patients with unilateral anterior circulation infarct [30 with large artery atherosclerosis (LAA), 13 with small vessel disease (SVD), and 17 with coexisting LAA and SVD] and 16 healthy controls were enrolled...
March 3, 2017: Journal of Stroke and Cerebrovascular Diseases: the Official Journal of National Stroke Association
https://www.readbyqxmd.com/read/28261153/non-invasive-respiratory-impedance-enhances-cerebral-perfusion-in-healthy-adults
#13
Christopher G Favilla, Ashwin B Parthasarathy, John A Detre, Arjun G Yodh, Michael T Mullen, Scott E Kasner, Kimberly Gannon, Steven R Messé
Optimization of cerebral blood flow (CBF) is the cornerstone of clinical management in a number of neurologic diseases, most notably ischemic stroke. Intrathoracic pressure influences cardiac output and has the potential to impact CBF. Here, we aim to quantify cerebral hemodynamic changes in response to increased respiratory impedance (RI) using a non-invasive respiratory device. We measured cerebral perfusion under varying levels of RI (6 cm H2O, 9 cm H2O, and 12 cm H2O) in 20 healthy volunteers. Simultaneous measurements of microvascular CBF and middle cerebral artery mean flow velocity (MFV), respectively, were performed with optical diffuse correlation spectroscopy and transcranial Doppler ultrasound...
2017: Frontiers in Neurology
https://www.readbyqxmd.com/read/28255331/detection-of-impaired-cerebral-autoregulation-using-selected-correlation-analysis-a-validation-study
#14
Martin A Proescholdt, Rupert Faltermeier, Sylvia Bele, Alexander Brawanski
Multimodal brain monitoring has been utilized to optimize treatment of patients with critical neurological diseases. However, the amount of data requires an integrative tool set to unmask pathological events in a timely fashion. Recently we have introduced a mathematical model allowing the simulation of pathophysiological conditions such as reduced intracranial compliance and impaired autoregulation. Utilizing a mathematical tool set called selected correlation analysis (sca), correlation patterns, which indicate impaired autoregulation, can be detected in patient data sets (scp)...
2017: Computational and Mathematical Methods in Medicine
https://www.readbyqxmd.com/read/28245206/cerebrovascular-and-cardiovascular-variability-interactions-investigated-through-conditional-joint-transfer-entropy-in-subjects-prone-to-postural-syncope
#15
Vlasta Bari, Beatrice De Maria, Claudio Enrico Mazzucco, Gianluca Rossato, Davide Tonon, Giandomenico Nollo, Luca Faes, Alberto Porta
A model-based conditional transfer entropy approach was exploited to quantify the information transfer in cerebrovascular (CBV) and cardiovascular (CV) systems in subjects prone to develop postural syncope. Spontaneous beat-to-beat variations of mean cerebral blood flow velocity (MCBFV) derived from a transcranial Doppler device, heart period (HP) derived from surface electrocardiogram, mean arterial pressure (MAP) and systolic arterial pressure (SAP) derived from finger plethysmographic arterial pressure device were monitored at rest in supine position (REST) and during 60° head-up tilt (TILT) in 13 individuals (age mean±standard deviation: 28±9 years, min-max range: 18-44 years, 5 males) with a history of recurrent episodes of syncope (SYNC) and in 13 age- and gender-matched controls (NonSYNC)...
February 28, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28244242/defining-hypotension-in-anesthetized-infants-by-individual-awake-blood-pressure-values-a-prospective-observational-study
#16
Frank Weber, Laurens Koning, Gail P Scoones
BACKGROUND: Blood pressure (BP) is the most commonly applied clinical surrogate parameter for tissue perfusion and cerebral autoregulation. Hypotension during anesthesia may contribute to unfavorable outcome in young children. Hypotension in anesthetized infants can be defined using BP values relative to individual awake baseline or absolute BP values. AIM: The aim of this study was to investigate the applicability of the two definitions and to compare the incidences of hypotension...
February 28, 2017: Paediatric Anaesthesia
https://www.readbyqxmd.com/read/28242827/postural-effects-on-cerebral-blood-flow-and-autoregulation
#17
Zachary K Garrett, James Pearson, Andrew W Subudhi
Cerebral autoregulation (CA) is thought to maintain relatively constant cerebral blood flow (CBF) across normal blood pressures. To determine if postural changes alter CA, we measured cerebral blood flow velocity (CBFv) in the middle cerebral arteries, mean arterial blood pressure (MABP), cardiac output (Q), and end-tidal carbon dioxide (PETCO2) in 18 healthy individuals (11 female and seven male; 26 ± 9 years) during repeated periods of supine and seated rest. Multiple regression was used to evaluate the influence of PETCO2, MABP, Q, and hydrostatic pressure on CBFv...
February 2017: Physiological Reports
https://www.readbyqxmd.com/read/28241122/numerical-investigation-of-vasospasm-detection-by-extracranial-blood-velocity-ratios
#18
Jaiyoung Ryu, Nerissa Ko, Xiao Hu, Shawn C Shadden
BACKGROUND: Early diagnosis of vasospasm following subarachnoid hemorrhage can prevent cerebral ischemia and improve neurological outcomes. This study numerically evaluates the relevance of extracranial blood velocity indices to detect vasospasm. METHODS: A numerical model of cerebral blood flow was used to evaluate the hemodynamics associated with anterior and posterior vasospasm under normal and impaired cerebral autoregulation conditions. Extracranial blood velocities at the carotid and vertebral arteries and their ratios between ipsilateral and contralateral, anterior and posterior, and downstream and upstream arteries were monitored during vasospasm progression...
February 28, 2017: Cerebrovascular Diseases
https://www.readbyqxmd.com/read/28227461/dynamic-modeling-of-apnea-induced-concurrent-variations-in-arterial-blood-pressure-and-cerebral-blood-flow-velocity
#19
Raichel Alex, Rong Zhang, Donald E Watenpaugh, Khosrow Behbehani, Raichel Alex, Rong Zhang, Donald E Watenpaugh, Khosrow Behbehani, Raichel Alex, Rong Zhang, Khosrow Behbehani, Donald E Watenpaugh
Obstructive Sleep Apnea (OSA) is characterized by partial (hypopnea) or complete cessation (apnea) of airflow to the lungs during sleep. It has been previously reported that apnea episodes lead to significant rise in instantaneous blood pressure concomitant with a rise in cerebral blood flow velocity, indicating loss of cerebral autoregulation during the episodes. In this study, we have used Auto Regressive Moving Average model (ARMA (na, nb, nk)) to quantify OSA induced dynamic changes in cerebral blood flow velocity (CBFV) with beat to beat blood pressure (BP) as an input...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226593/dynamic-cerebral-autoregulation-in-young-athletes-following-concussion
#20
Kyriaki Kostoglou, Alexander D Wright, Jonathan D Smirl, Kelsey Bryk, Paul van Donkelaar, Georgios D Mitsis, Kyriaki Kostoglou, Alexander D Wright, Jonathan D Smirl, Kelsey Bryk, Paul van Donkelaar, Georgios D Mitsis, Paul van Donkelaar, Alexander D Wright, Kyriaki Kostoglou, Jonathan D Smirl, Kelsey Bryk, Georgios D Mitsis
The purpose of this study was to examine cerebral autoregulation (CA) in young athletes experiencing concussion. The subjects were monitored and repeatedly tested 72 hours, 2 weeks and 1 month post-injury. Mean arterial blood pressure (MABP), end-tidal partial pressure of carbon dioxide (PETCO2) and cerebral blood flow velocity (CBFV) in the middle and posterior cerebral arteries were monitored during mental activation paradigms. In order to characterize CA we employed autoregressive models with exogenous inputs (ARX) and impulse response models based on the Laguerre expansion technique (LET)...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
keyword
keyword
14074
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"