Middle Cerebral Artery Blood Flow Research Articles

The value of ultrasound spectra of middle cerebral artery and umbilical artery blood flow in adverse pregnancy outcomes.

To evaluate the diagnostic value of ultrasound spectra of the middle cerebral artery (MCA) and umbilical artery (UA) blood flow in predicting adverse pregnancy outcomes. Data from 202 late singleton pregnancies (32-34weeks gestation) were analyzed. Group A included 155 normal pregnancies, while Group B comprised 47 high-risk pregnancies. Color Doppler ultrasonography was used to measure and compare pulsatility index (PI), resistance index (RI), and end-systolic peak/end-diastolic peak (S/D) ratios of fetal MCA and UA between the groups. UA-related parameters (PI, RI, and S/D) were significantly higher in Group B compared to Group A, whereas MCA-related parameters (PI, RI, and S/D) were significantly lower in Group B than in Group A. In pregnancies with adverse outcomes, fetal UtA and UA-related parameters were elevated, while MCA parameters were decreased compared to those with favorable outcomes. Ultrasound spectra of MCA and UA blood flow provide valuable clinical information for assessing fetal intrauterine growth and predicting adverse pregnancy outcomes.

Association of high-sensitivity cardiac troponin T with territorial middle cerebral artery brain infarctions and dynamic cerebral autoregulation.

Cardiac high-sensitivity troponin T (hs-cTnT) is linked to the cardioembolic origin, severity, and outcome of acute ischemic stroke. Furthermore, larger brain infarctions are often accompanied by impaired dynamic cerebral autoregulation (dCA), which is also indicative of a poor prognosis. This study aimed to investigate whether hs-cTnT levels can serve as a predictor of dCA impairment. Retrospective cohort study. In 330 consecutive patients with stroke (age 71years [IQR 59-78]; 100 women; 229 territorial and 111 non-territorial brain infarcts) with successful dCA assessment, hs-cTnT levels were measured within 24hours of stroke onset. These measurements were analyzed in relation to cerebrovascular risk factors, stroke origin, stroke severity (National Institute of Health Stroke Scale, NIHSS at entry), modified Rankin scale (mRs) at 3months, and stroke volume determined by cranial computed tomography perfusion (CTP). dCA was assessed using transfer function analysis, which assessed the relationship between middle cerebral artery blood flow velocity and blood pressure. Coherence, gain, and phase were estimated across 3 frequency ranges: very low (0.02-0.07Hz), low (0.07-0.15Hz), and high (0.15-0.5Hz). In univariate analysis, hs-cTnT was associated with cardioembolism and territorial infarction. In the multinomial logistic regression analysis, independent risk factors for the presence of a territorial infarction included atrial fibrillation, the NIHSS score, the infarct core on CTP, cardioembolism, and large vessel disease, but not hs-cTnT levels. Risk factors for a poor outcome (mRs >2) included age, hs-cTnT, and NIHSS score. Overall, the coherence, gain, and phase were not predicted by hs-cTnT levels. Hs-cTnT levels are associated with poor stroke outcomes. However, they do not predict dCA impairment. ClinicalTrials.gov NCT04611672, 11.10.2020.

Prolonged intracranial catheter dwell time exacerbates penumbral stress and worsens stroke thrombectomy outcomes

BackgroundThe duration of mechanical thrombectomy (MT) is a negative predictor of outcomes in acute ischemic stroke (AIS), yet the precise mechanisms are unclear. We investigated whether the placement of large-bore...

Correlation between antihypertensive drugs and cerebral hemodynamic parameters: insights from observational findings using transcranial Doppler.

Antihypertensives (AHD) can influence cerebral autoregulation (CA) and attenuate hypertrophic concentric remodelling of arterioles. The aim of this study was to examine the associations between AHD, CA and structural and functional properties of cerebral arteries. In this observational, cross-sectional study 115 volunteers were divided in group 1 (non-hypertensive) [n = 30]; group 2 (hypertensive with systolic blood pressure [SBP] < 140 and diastolic blood pressure [DBP] < 90 mmHg) [n = 54]; group 3 (hypertensive with SBP ≥ 140 or DBP ≥ 90 mmHg) [n = 31] and simultaneous measurements of systemic blood pressure (BP) and middle cerebral artery blood flow velocity (CBFV) were obtained from digital plethysmography and transcranial Doppler. Beat-to-beat, critical closing pressure (CrCP), resistance-area product (RAP) and autoregulation index (ARI) values were extracted by linear regression analysis of instantaneous BP and CBFV waveforms using computerised analysis. Pulsatility index (PI) was calculated and CO2 reactivity was assessed by the breath-holding test. Despite their higher RAP (1.7 [±0.7], p < 0.001) compared to groups 1 and 2, uncontrolled hypertensive using diuretics (p = 0.047) and α2-agonists (p = 0.009) had significantly lower PI. Impaired CO2 reactivity was common between the two hypertensive groups (p = 0.008), however ARI, CrCP and CBFV did not differ between them and non-hypertensive individuals and also did not correlate with any AHD used. Unlike the RAP, PI does not seem to reflect the real cerebrovascular resistence resulting from chronic arterial remodelling. Despite impaired CO2 reactivity, hypertensivehavearterial tonus and CA comparable to non-hypertensive. Experimental studies involving an untreated hypertensive control group are required to robustly make definitive conclusions about these questions.

Cerebral Overperfusion Despite Reduced Cortical Metabolism Is Associated with Postoperative Delirium in Cardiac Surgery Patients: A Prospective Observational Study.

Background: Decreased cerebral oximetry (rSO2) in cardiac surgery is associated with postoperative delirium (POD). However, interventions optimizing intraoperative rSO2 are inconclusive. Methods: In this prospective observational cohort study, the relationship between rSO2, middle cerebral artery blood flow velocity (MCAV), and processed EEG was assessed in cardiac surgery patients with and without POD. MCAV was continuously recorded by transcranial Doppler sonography (TCD), together with continuous rSO2 and bispectral index (BIS) monitoring. Cardiopulmonary bypass (CPB) flow rate was adjusted according to body surface area. The cohort was divided into the POD and control groups, according to the postoperative results of the confusion assessment method (CAM/CAM-ICU), the 4A's test (4AT), and the Delirium Observation Scale (DOS). A mixed model analysis was performed for intraoperative raw data. The cerebral autoregulation index was calculated from TCD, rSO2, and arterial pressure values. Differences in impaired autoregulation were compared using the Mann-Whitney U test. Results: A total of 41 patients were included in this study. A total of 13 patients (36.11%) developed postoperative delirium. There were no significant differences in the baseline characteristics of patients with or without POD. Patients with POD had lower BIS values during CPB (adjusted mean difference -4.449 (95% CI [-7.978, -0.925])). RSO2 was not significantly reduced in POD, (adjusted mean difference: -5.320, 95% CI [-11.508, 0.874]). In contrast, MCAV was significantly increased in POD (10.655, 95% CI [0.491, 20.819]). The duration of cerebral autoregulation impairment did not differ significantly for TCD and cerebral oximetry-derived indices (p = 0.4528, p = 0.2715, respectively). Conclusions: Our results suggest that disturbed cerebral metabolism reflects a vulnerable brain which may be more susceptible to overperfusion during CPB, which can be seen in increased MCAV values. These phenomena occur irrespectively of cerebral autoregulation.

Ventilatory response to head-down-tilt in healthy human subjects.

Postural fluid shifts may directly affect respiratory control via a complex interaction of baro- and chemo-reflexes, and cerebral blood flow. Few data exist concerning the steady state ventilatory responses during head-down tilt. We examined the cardiorespiratory responses during acute 50° head-down tilt (HDT) in 18 healthy subjects (mean [SD] age 27 [10] years). Protocol 1 (n=8, two female) was 50° HDT from 60° head-up posture sustained for 10min, while exposed to normoxia, normoxic hypercapnia (5% CO2), hypoxia (12% inspired O2) or hyperoxic hypercapnia (95% O2, 5% CO2). Protocol 2 (n=10, four female) was 50° HDT from supine, sustained for 10min, while breathing either medical air or normoxic hypercapnic (5% CO2) gas. Ventilation ( , pneumotachograph), end-tidal O2 and CO2 concentration and blood pressure (Finapres) were measured continuously throughout each protocol. Middle cerebral artery blood flow velocity (MCAv; transcranial Doppler) was also measured during protocol 2. Ventilation increased significantly (P<0.05) compared to baseline during HDT in both hyperoxic hypercapnia (protocol 1 by mean [SD] 139 [26]%) and normoxic hypercapnia (protocol 1 by mean [SD] 131 [21]% and protocol 2 by 129 [23]%), despite no change in or from baseline. No change in was observed during HDT with medical air or hypoxia, and there was no significant change in MCAv during HDT compared to baseline. The absence of change in cerebral blood flow leads us to postulate that the augmented ventilatory response during steep HDT may involve mechanisms related to cerebral venous pressure and venous outflow.

Transcranial Doppler ultrasound in evaluating cerebral blood flow abnormalities in major depressive disorder.

Previous research has shown that blood flow abnormalities affect major depressive disorder (MDD) from multiple perspectives. Therefore, this study aims to investigate the relationship between middle cerebral artery (MCA) blood flow velocity parameters and clinical symptom scores (Hamilton Depression Rating Scale [HAMD] and Montgomery-Åsberg Depression Rating Scale [MADRS]) in patients with MDD. We compared the MCA blood flow velocity parameters, including peak systolic velocity (MCA-PSV), end-diastolic velocity (MCA-EDV), and mean velocity (MCA-MV), between 50 MDD patients and 50 control subjects. Additionally, we analyzed the correlation between these parameters and HAMD and MADRS scores. Hemodynamic parameters such as pulsatility index and resistance index were also compared between the 2 groups. MCA-PSV, MCA-EDV, and MCA-MV were significantly lower in MDD patients compared to the control group, while pulsatility index and resistance index were significantly higher. Correlation analysis revealed that MCA-PSV, MCA-EDV, and MCA-MV were significantly negatively correlated with HAMD and MADRS scores in MDD patients, indicating that cerebral blood flow velocity decreases as depressive symptoms worsen. Furthermore, regression analysis confirmed the negative relationship between blood flow velocity parameters and clinical symptom scores. The results of this study suggest that the reduction in cerebral blood flow velocity in MDD patients may be associated with the severity of depressive symptoms. This finding provides new insights into the pathophysiological mechanisms of MDD and offers a potential theoretical basis for developing depression treatment strategies based on cerebral blood flow velocity parameters.

Comparison of inhalational and intravenous anesthesia induction on electroencephalogram and cerebral perfusion in children with congenital heart disease: A secondary analysis of a randomized controlled trial

ObjectiveThe effects of anesthetics on electroencephalograms and cerebral perfusion remain understudied in children with congenital heart disease. With regard to this, we compared inhalational anesthesia induction and intravenous anesthesia induction. DesignA randomized controlled trial. SettingOperation room in two tertiary hospitals. ParticipantsA cohort of 116 pediatrics patients undergoing cardiac surgery. Measurements and main resultsThe patients were randomly assigned to either the intravenous group (n=58) or the inhalational group (n=58). The inhalational group received anesthesia induction with 4-6% sevoflurane and a bolus of pipecuronium 0.2 mg/kg, while the intravenous group received anesthesia induction with intravenous midazolam 0.2 mg/kg, pipecuronium 0.2 mg/kg, and sufentanil 1 μg/kg. Ten minutes after tracheal intubation, the following parameters were measured: spectral edge frequency, burst suppression event, patient state index, middle cerebral artery blood flow velocity, cerebral oxygen saturation, and hemodynamic parameters. In comparison to the intravenous group, the inhalational group exhibited significant increases in 95% spectral edge frequency, ratio of burst suppression event, blood flow velocity in the middle cerebral artery, and cerebral oxygen saturation (P<0.05 for all), as well as decreases in systolic pressure, diastolic pressure, cardiac index, and the maximal slope of systolic upstroke (P<0.05 for all). ConclusionThe administration of sevoflurane for anesthesia induction results in more burst suppression, while also demonstrating superior cerebral perfusion when compared to the use of intravenous medications for anesthesia induction.

Optimizing Brain-Computer Interfaces for Methampetamine Use Disorder through Quantitative Electroencephalography (QEEG) and Transcranial Doppler Analysis: Article Review

A Brain-Computer Interface (BCI) is a system that allows a person to control external devices using only their brain activity. It works by translating brain signals into commands that can be understood by a computer. Several lines of evidence demonstrated the deleterious effect of methamphetamine (MA) on neurological and psychological functions. The use of amphetamines, such as MA, is associated with cerebrovascular complications such as cerebrovascular accidents (CVA) ,hemorrhage, hypoxic damage and vasculitis. Interestingly, while changes to cerebral blood flow (CBF) in response to acute amphetamine exposure have been reported. Transcranial Color Doppler (TCCD) is a non-invasive medical imaging technique that uses ultrasound waves to measure blood flow velocity in the major arteries of the brain, specifically within the circle of Willis. The research paper you referenced explores the use of TCCD as a potential measurement modality for BCIs. Quantitative electroencephalogram (qEEG) is a powerful tool for understanding brain function qEEG can reveal specific brain wave patterns associated with drug addiction, potentially providing insights into the neurobiological mechanisms underlying cravings, withdrawal symptoms, and relapse risk in Methamphetamine User Disorder (MUD). There is growing research interest in using Transcranial dopller as a measurement modality for BCIs.Here are some of the key considerations for using Transcranial doppler in BCIs: Mental Tasks, signal processing and classification, accuracy and reliability. Transcranial doppler provides information about blood flow in specific arteries but lacks detailed spatial information about brain activity. These patterns could vary depending on the type of drug, the severity of addiction, and individual differences. Transcranial doppler in measuring middle cerebral artery (MCA) blood flow velocity parameters (peak systolic velocity (PSV) and mean flow velocity (MFV)). qEEG can help researchers investigate the complex interplay between addiction and other brain disorders, like depression or anxiety. Characteristic qEEG in drugs addiction Increased Theta (4-8 Hz) and delta (1-4 Hz) brain waves are often associated with sleep and relaxation. However, research has shown that individuals with drug addiction may have increased theta and delta activity, particularly in the frontal and temporal regions of the brain. Altered Beta (13-30 Hz) brain waves are generally associated with wakefulness, alertness, and cognitive processing. Studies have observed both increases and decreases in beta activity in individuals with drug addiction, depending on the type of drug, the stage of addiction, and the specific brain regions being examined. The results of this research have important practical implications for building an diagnostic and functional assement with a better understanding of an using technology.

Real-time monitoring of middle cerebral artery blood flow using intraoperative transcranial doppler during trans-carotid artery revascularization

ObjectiveTranscarotid artery revascularization (TCAR) has emerged as a safe and effective method for carotid revascularization, offering several key advantages over carotid endarterectomy (CEA) and carotid artery stenting (CAS). Intraoperative transcranial Doppler (TCD) monitoring plays a pivotal role in assessing cerebral hemodynamics and detecting embolic signals during TCAR at our institution. MethodsThis review synthesizes the current literature and provides guidance for TCD monitoring throughout the various phases of TCAR, from preoperative assessment to postoperative management. Key considerations include probe placement, waveform evaluation, interpreting monitoring parameters such as mean flow velocity (MFV), pulsatility index (PI), and percentage change in the MFV (Δ%). Techniques for maintaining the insonation of the middle cerebral artery (MCA) M1 segment and optimal parameter settings for intraoperative TCD monitoring are detailed. ResultsTCAR phases are highlighted, including transcarotid access and vessel control, sheath insertion, the establishment of flow reversal, pre-dilation, stent placement, post-dilation, and closure, while emphasizing the importance of real-time feedback provided by TCD monitoring in identifying embolic signals and assessing changes in cerebral perfusion. The review discusses limitations of TCD monitoring, such as inadequate temporal windows, incorrect vessel identification and reliability issues with automatic emboli detection counters. Furthermore, practical advice is provided on how to navigate common pitfalls encountered during intraoperative TCD monitoring. ConclusionBy understanding the nuances of TCD monitoring and its application in TCAR, intraoperative TCD monitoring may aid to minimize the low but potential risk of intraprocedural embolic events, periprocedural hypoperfusion and postoperative hyperperfusion. Finally, we suggest opportunities for further research in embolization quantification and additional strategies to optimize quality control in TCAR.

SEX DIFFERENCES IN CEREBRAL BLOOD FLOW VELOCITY RESPONSES TO EXERCISE IN THE HEAT

INTRODUCTION &amp; AIMS Global warming poses a risk for the development of heat-related physiological impairment, which can be aggravated when exercising in hot conditions. The aim of the present study was to investigate acute effects of exercising in hot conditions on cerebral blood flow velocity and systolic function in healthy individuals and to explore possible sex differences. METHODS The experimental condition consisted of walking on a treadmill, at 5km/h and 2% incline, inside a heat chamber at 40°C (50%RH), for 90 minutes. Middle cerebral artery blood flow velocity (MCAv) and left ventricular global longitudinal strain (GLS; a sensitive index of systolic function), were assessed at baseline and every 30 minutes by means of transcranial Doppler and speckle-tracking echocardiography, respectively. Data is expressed in delta (Δ) and standard error. RESULTS Twenty-six individuals (13♂,13♀ 27.1±1.0yrs, P=0.02) completed the experimental protocol. Both males and females exhibited non-significant increases in MCAv from baseline at 30 minutes (♂Δ=2.55±2.15 P&amp;gt;0.05; ♀Δ=0.54±2.53cm.s-1, P&amp;gt;0.05; interaction P=0.63), followed by significant decreases relative to 30min, at 60min (♂Δ=-4.0±1.23 P=0.04; ♀Δ=-5.41±1.56cm.s-1, P=0.03; interaction P=0.63) and 90 minutes (♂Δ=-6.08±1.37 P&amp;lt;0.01; ♀Δ=-7.39±1.40cm.s-1, P&amp;lt;0.01; interaction P=0.63). In males, there was a significant decrease in GLS from baseline at 30min (Δ=2.44±0.69%, P&amp;lt;0.05), 60 (Δ=2.79±0.73%, P=0.03), and 90 (Δ=3.49±0.89%, P=0.03) minutes; no significant changes were observed in females. CONCLUSION Males and females presented similar patterns of change in cerebral blood flow velocity, including significant decreases with prolonged heat exertion. These changes occur in both sexes, despite changes in systolic strain only being apparent in males. These data suggest that sex differences may exist in the regulation of cerebrovascular responses to exercise in the heat in humans.

Non-vascular ATP-sensitive potassium channel activation does not trigger migraine attacks: A randomized clinical trial.

To investigate the role of NN414, a selective KATP channel opener for the Kir6.2/SUR1 channel subtype found in neurons and β-pancreatic cells, in inducing migraine attacks in individuals with migraine without aura. Thirteen participants were randomly allocated to receive NN414 and placebo on two days separated by at least one week. The primary endpoint was the difference in the incidence of migraine attacks after NN414 compared with placebo. The secondary endpoints were the difference in the area under the curve for headache intensity scores, middle cerebral artery blood flow velocity (VMCA), superficial temporal artery diameter, heart rate and mean arterial pressure. Twelve participants completed the study, with two (16.6%) reporting migraine attacks after NN414 compared to one (8.3%) after placebo (p = 0.53). The area under the curve for headache intensity, VMCA, superficial temporal artery diameter, heart rate and mean arterial pressure did not differ between NN414 and placebo (p > 0.05, all comparisons). The lack of migraine induction upon activation of the Kir6.2/SUR1 channel subtype suggests it may not contribute to migraine pathogenesis. Our findings point to KATP channel blockers that target the Kir6.1/SUR2B subtype, found in cerebral vasculature, as potential candidates for innovative antimigraine treatments.Registration number: NCT04744129.

Dietary Effect on Peripheral and Cerebral Vascular Function in Adults with Non-Alcoholic Fatty Liver Disease

Objective: Non-alcoholic fatty liver disease (NAFLD) is a recognized independent risk factor for cardiovascular and cerebrovascular dysfunction. The present study evaluated the effect of dietary interventions on peripheral and cerebral vascular function in individuals with NAFLD. Methods: We studied 30 middle-aged adults (55±9 years) with NAFLD or with elevated NAFLD risk (with prediabetes symptoms). Liver fat content was assessed via 1H magnetic resonance spectroscopy. NAFLD was defined as liver fat proton density fat fraction (PDFF) exceeding 5%. Participants were randomly assigned to a low-carbohydrate diet (carbohydrate intake &lt;30 g/d) or a low-calorie diet (30% calorie intake reduction). Arterial stiffness (via brachial-ankle pulse wave velocity-baPWV), carotid artery intima-media thickness (IMT), endothelium-dependent vasodilation (via flow-mediated dilation-FMD), cerebrovascular reactivity (CVR) in the middle cerebral artery (MCA), and blood concentrations of cardiovascular risk factors were measured before and after a two-week dietary intervention. Results: Participants with NAFLD represented 70% of the current cohort. Following the dietary interventions, participants had significant reductions in body weight (95%CI [-3.22, -1.41 kg]) and fat mass (95%CI [-1.64, -0.56 kg]), accompanied by decreased liver fat content (95%CI [-2.62, -0.79%]). These changes were only evident in the NAFLD group with no significant differences between the two dietary interventions. Systolic and diastolic blood pressure as well as pulse pressure significantly decreased in both NAFLD and non-NAFLD groups. Total cholesterol (95%CI [-22.2, -1.5 mg/dL]) and triglyceride (95%CI [-30.4, -0.9 mg/dL]) concentrations decreased in those with NAFLD assigned to the low-carbohydrate diet. baPWV decreased (95%CI [-78.6, -12.4 cm/s]) only in individuals with NAFLD assigned to the low-calorie diet. FMD significantly increased (95%CI [0.5, 5.1%]) only in individuals with NAFLD assigned to the low-carbohydrate diet. Lower baseline liver fat content was associated with greater improvement in FMD (r=-0.60, p=0.008) in the NAFLD group. Carotid IMT and cerebrovascular parameters (e.g., pulsatility index, CVR, MCA blood flow velocity) remained unchanged in any groups. Changes in vascular function were not associated with the corresponding changes in liver fat content. Conclusion: The two-week dietary intervention involving either a low-carbohydrate or low-calorie diet elicited significant reductions in liver fat content and improvements in peripheral arterial stiffness and endothelium-dependent vasodilation in adults with NAFLD. UT Aging Initiatives. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Statin treatment intensity and cerebral vasomotor reactivity response in patients with ischemic stroke.

Cerebral vasomotor reactivity (VMR) is vital for regulating brain blood flow and maintaining neurological function. Impaired cerebral VMR is linked to a higher risk of stroke and poor post-stroke outcomes. This study explores the relationship between statin treatment intensity and VMR in patients with ischemic stroke. Seventy-four consecutive patients (mean age 69.3 years, 59.4% male) with recent ischemic stroke were included. VMR levels were assessed 4 weeks after the index stroke using transcranial Doppler, measuring the breath-holding index (BHI) as an indicator of the percentage increase in middle cerebral artery blood flow (higher BHI signifies higher VMR). Multistep multivariable regression models, adjusted for demographic and cerebrovascular risk factors, were employed to examine the association between statin intensity treatment and BHI levels. Forty-one patients (55%) received high-intensity statins. Patients receiving high-intensity statins exhibited a mean BHI of 0.85, whereas those on low-intensity statins had a mean BHI of 0.67 (mean difference 0.18, 95% confidence interval: 0.13-0.22, p-value<.001). This significant difference persisted in the fully adjusted model (adjusted mean values: 0.84vs. 0.68, p-value:.008). No significant differences were observed in BHI values within patient groups on high-intensity or low-intensity statin therapy (all p-values>.05). Furthermore, no significant association was found between baseline low-density lipoprotein (LDL) levels and BHI. High-intensity statin treatment post-ischemic stroke is linked to elevated VMR independent of demographic and clinical characteristics, including baseline LDL level. Further research is needed to explore statin therapy's impact on preserving brain vascular function beyond lipid-lowering effects.

The association between cerebral blood flow variations during on-pump coronary artery bypass grafting surgery and postoperative delirium.

Postoperative delirium (POD) has a major impact on patient recovery after cardiac surgery. Although its pathophysiology remains unclear, there could be a correlation between cerebral blood flow (CBF) variations during cardio-pulmonary bypass (CPB) and POD. Our study aimed to evaluate whether variations in on-pump CBF, compared to pre-anesthesia and pre-CPB values, are associated with POD following coronary artery bypass grafting (CABG) surgery. This prospective observational cohort study included 95 adult patients undergoing elective on-pump CABG surgery. Right middle cerebral artery blood flow velocity (MCAV) was assessed using Transcranial Doppler before anesthesia induction, before CPB and every fifteen minutes during CPB. Pre-anesthesia and pre-CPB values were chosen as baselines. Individual values, measured during CPB, were converted as percentage changes relative to these baselines and named as %MCAV0 and %MCAV1, respectively. POD was assessed using the Confusion Assessment Method for ICU (CAM-ICU) during the first 48 post-operative hours and with the 3-Minute Diagnostic Interview for Confusion Assessment Method (3D-CAM) on the fifth post-surgical day. Overall POD incidence was 17.9%. At 30minutes of CPB, %MCAV0 was higher in POD group than in no-POD group (p = .05). %MCAV0 at 45minutes of CPB was significantly higher in POD group (87 (±17) %) than in no-POD group (68 (±24) %), p = .04. %MCAV1 at 30 and 45minutes of CPB were higher in POD group than in no-POD group, at the limit of statistical significance. We found %MCAV1 > 100% in POD group, but not in no-POD group. Significant differences in %MCAV0 became evident after 30minutes of CPB, whereas differences in %MCAV1 at 45 minutes of CPB were at limit of statistical significance. In POD group %MCAV1 was higher than 100% at 30 and 45minutes of CPB, which is supposed to be a sign of cerebral hyperperfusion. Monitoring CBF during CPB could have prognostic value for POD.

Effect of continuous 2MHz transcranial ultrasound as an adjunct to tenecteplase thrombolysis in acute anterior circulation ischemic stroke patients: an open labeled non-randomized clinical trial.

The treatment of acute ischemic stroke has improved in last few decades. While meta-analyses of several trials have established the safety and efficacy of Intravenous (IV) Tenecteplase thrombolysis, concomitant continuous transcranial doppler (TCD) ultrasound administration has not been assessed in any clinical trial. The aim of this study was to determine the effects of continuous 2MHz TCD ultrasound during IV Tenecteplase thrombolysis for Middle cerebral artery (MCA) stroke. A total of 19 patients were included, 13 received TCD ultrasound and 6 sham TCD with IV Tenecteplase. TCD spectrum and difference in Pre and post TCD parameters were measured. Asymptomatic hemorrhagic transformation of infarct wasseen in two patients. There was no mortality or clinical worsening in thesonothrombolysis group as against sham sonothrombolysis group. Median of peak systolic velocity wasincreased in both thesonothrombolysis (P = 0.0002) and sham sonothrombolysis group (P-value = 0.001). The difference in change in mean flow velocity between two groups, sonothrombolysis (11cm/sec)and sham sonothrombolysis (3.5cm/sec) were also significantly different (P = 0.014). This pilot work has established safety of continuous 30min TCD application along with IV Tenecteplase thrombolysis and it concludes thatconcomitant 2MHz TCD ultrasound administration significantly increased the MCA blood flow compared to chemothrombolysis alone.CTRI Registered Number: CTRI/2021/02/031418.

Investigating the effects of tilting the postural drainage lithotripsy system on cerebral blood flow, intracranial pressure, heart rate, and blood pressure

PurposeTo investigate the effect of the postural drainage lithotripsy system developed by our experimental team on the vital signs of patient with urinary stones during the stone removal process.MethodsFour groups of 15 subjects (0°, 10°, 40°, and 70°) were subjected to different angles of head-down tilt to measure middle cerebral artery blood flow velocity (MCAv), cerebrovascular conductance coefficient (CVCi), intracranial pressure (nICP), heart rate (HR), and mean arterial blood pressure (MAP).ResultsAs the angle of HDT changed, MCAv values, nICP values, CVCi values, HR values, and MAP values changed significantly (all P ≤ 0.001), and the difference was statistically significant. During 10°HDT, despite a slight increase in nICP, the other measurements remained stable. During 40°HDT, only the MCAv values did not change significantly, whereas the rest of the measures were significantly altered. During 70°HDT, all indicators changed significantly.ConclusionsThe significant alterations in cerebral blood flow, intracranial pressure, and hemodynamics induced during the treatment of renal residual fragments with postural drainage should be used with caution in individuals with cerebrovascular accidents.China Clinical Trials RegistryChiCTR2300070671; Registration date: 2023-04-18.

A Comparative Study of Transcranial Color-Coded Doppler (TCCD) and Transcranial Doppler (TCD) Ultrasonography Techniques in Assessing the Intracranial Cerebral Arteries Haemodynamics.

Cerebrovascular disease (CVD) poses a major public health and socio-economic burden worldwide due to its high morbidity and mortality rates. Accurate assessment of cerebral arteries' haemodynamic plays a crucial role in the diagnosis and treatment management of CVD. The study compared a non-imaging transcranial Doppler ultrasound (TCD) and transcranial color-coded Doppler ultrasound (with (cTCCD) and without (ncTCCD)) angle correction in quantifying middle cerebral arteries (MCAs) haemodynamic parameters. A cross-sectional study involving 50 healthy adults aged ≥ 18 years was conducted. The bilateral MCAs were insonated via three trans-temporal windows (TTWs-anterior, middle, and posterior) using TCD, cTCCD, and ncTCCD techniques. The MCA peak systolic velocity (PSV) and mean flow velocity (MFV) were recorded at proximal and distal imaging depths that could be visualised on TCCD with a detectable spectral waveform. A total of 152 measurements were recorded in 41 (82%) subjects with at least one-sided open TTW across the three techniques. The mean PSVs measured using TCD, ncTCCD, and cTCCD were 83 ± 18 cm/s, 81 ± 19 cm/s, and 93 ± 21 cm/s, respectively. There was no significant difference in PSV between TCD and ncTCCD (bias = 2 cm/s, p = 1.000), whereas cTCCD yielded a significantly higher PSV than TCD and ncTCCD (bias = -10 cm/s, p < 0.001; bias = -12 cm/s, p ≤ 0.001, respectively). The bias in MFV between TCD and ncTCCD techniques was (bias = -0.5 cm/s; p = 1.000), whereas cTCCD demonstrated a higher MFV compared to TCD and ncTCCD (bias = -8 cm/s, p < 0.001; bias = -8 cm/s, p ≤ 0.001, respectively). TCCD is a practically applicable imaging technique in assessing MCA blood flow velocities. cTCCD is more accurate and tends to give higher MCA blood flow velocities than non-imaging TCD and ncTCCD techniques. ncTCCD is comparable to non-imaging TCD and should be considered in clinical cases where using both TCD and TCCD measurements is needed.

Effects of butylphthalide on cerebral vascular circulation, coagulation function, and neurological function in patients with acute severe ischemic stroke following intravenous thrombolysis: a preliminary study

Objective To analyze the effects of Butylphthalide on cerebral vascular circulation, coagulation function, and neurological function in patients with acute severe ischemic stroke following intravenous thrombolysis. Methods Clinical efficacy, cerebral vascular circulation indicators [anterior cerebral artery (ACA), middle cerebral artery (MCA), vertebral artery (VA) blood flow velocity], coagulation function indicators [prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (FIB)], neurological function indicators [Activities of Daily Living (ADL) score. Results The total effective rate of treatment in the control group was 76.47%, while in the observation group, it was 96.08%, with the observation group showing a significantly higher total effective rate than the control group (p < 0.05). Before treatment, there was no significant difference in ACA, MCA, and VA blood flow velocity between the two groups (p > 0.05). However, after treatment, the ACA, MCA, and VA blood flow velocity in the observation group were significantly higher than those in the control group (p < 0.05). Before treatment, there was no significant difference in PT, APTT, TT, and FIB levels between the two groups (p > 0.05). Conclusion In patients with acute severe ischemic stroke undergoing intravenous thrombolysis, the addition of Butylphthalide to the treatment regimen yields favorable clinical outcomes. Compared to Alteplase alone, the addition of Butylphthalide further improves cerebral vascular circulation and coagulation function, promoting the recovery and reconstruction of neurological function in patients. Importantly, the addition of Butylphthalide does not increase the risk of adverse reactions, making it a safe and ideal option for clinical application.

Cerebral Hemodynamics and Vagally Mediated HRV Associated with High- and Low-frequency Yoga Breathing: An Exploratory, Randomized, Crossover Study.

Volitionally modifying respiration leads to changes in middle cerebral arterial (MCA) blood flow. The effect of changes in breath rate on MCA blood flow has not been reported. To determine the effect of slow (bumblebee yoga breathing) and fast (high frequency yoga breathing) yoga breathing techniques on MCA blood flow and vagally mediated heart rate variability. Thirty participants (mean age ± standard deviation, 27.3 ± 4.2 years) were assessed on 2 separate days practicing either high frequency yoga breathing (HFYB, breath frequency 54.2/min) or slow frequency bumblebee yoga breathing (BBYB, breath frequency 3.8/min) in random order to determine the effects of changes in breath frequency on MCA hemodynamics. Assessments included transcranial Doppler sonography, vagally mediated heart rate variability (VmHRV), and respiration. Both HFYB and BBYB (i) reduced MCA flow velocities, i.e., peak systolic, end diastolic, and mean flow velocities, and (ii) increased MCA pulsatility indices. There was an increase in VmHRV during BBYB based on increased power in high frequency (HF) and low frequency (LF). LF reflects VmHRV for slow breath frequencies. In BBYB the average breath rate was 3.8 breaths/min. In contrast, VmHRV decreased during HFYB (based on reduced HF power; repeated measures analysis of variance, P < 0.05, all cases). Hence, irrespective of the differences in breath frequency, both HFYB and BBYB appear to reduce MCA flow velocities and increase the resistance to blood flow bilaterally, although the VmHRV changed in opposite directions. MCA velocity and pulsatility changes are speculated to be associated with low global neural activity during yoga breathing.