Similar outcomes of arteriovenous fistulae created under general or regional anesthesia.

BACKGROUND: There is growing evidence that type of anesthesia can significantly change vascular access surgery outcomes. Still, there is limited evidence on the impact of regional anesthesia (RA) on patency and failure rates compared to general anesthesia (GA). The aim of this study was to compare the outcomes of RA and GA in patients who underwent vascular access creation at our center. METHODS: Data collected in our prospectively maintained database of patients with chronic renal dysfunction requiring hemodialysis were analyzed, 464 patients were included. Outcome parameters such as maturation, primary failure, postoperative flow measurements, patency rates, and survival outcomes were compared between RA and GA groups. RESULTS: In this study 489 vascular access procedures were performed in 464 patients, 318 included in the RA group and 171 in the GA group. Median follow-up time was 29.9 (IQR 37.3) months in the RA group versus 33.0 (IQR 40.7) in the GA group (p = 0.252). Anesthesia type did not significantly affect patient survival (HR, 1.01; CI, 0.70-1.45; p = 0.976). No significant differences were found in vascular access flow volume, primary failure, or time to cannulation between the RA and GA groups for both radiocephalic arteriovenous fistulae and brachiocephalic arteriovenous fistulae. Anesthesia type did not significantly change patency outcomes. CONCLUSIONS: Based on our results, both RA and GA demonstrate similar results regarding patient survival, maturation, failure, or patency after vascular access creation. Still, patient-specific factors for each type of anesthesia as well as patient preference should be considered.

Near-infrared spectroscopy monitoring during endovascular treatment for acute ischaemic stroke.

Introduction: The aim of endovascular treatment (EVT) for acute ischaemic stroke is to relieve the cerebral tissue hypoxia in the area supplied by the occluded artery. Near-infrared spectroscopy (NIRS) monitoring is developed to assess regional cerebral tissue oxygen haemoglobin saturation (rSO2). We aimed to investigate whether NIRS can detect inter- and intra-hemispheric rSO2 differences during EVT. Patients and methods: In this prospective, observational study, patients undergoing EVT for a proximal intracranial occlusion of the anterior circulation between May 2019 and November 2020, were included. A four-wavelength NIRS monitor (O3® Regional Oximeter (Masimo, Irvine, CA)) was used to measure rSO2 during EVT with sensors placed over the temporal lobes in 20 patients and over the frontal lobes in 13 patients. The Wilcoxon signed-rank test was used to test for inter-hemispheric rSO2 differences after groin puncture and after recanalisation, and intra-hemispheric rSO2 changes before and after recanalisation. Results: In the temporal cohort, no inter-hemispheric rSO2 differences were observed after groin puncture (median [IQR] rSO2 affected hemisphere, 70% [67-73] and unaffected hemisphere, 70% [66-72]; p = 0.79) and after recanalisation. There were no intra-hemispheric rSO2 changes over time. In the frontal cohort, no inter- and intra-hemispheric rSO2 differences or changes were found. Discussion and conclusion: A NIRS monitor could not detect inter- and intra-hemispheric rSO2 differences or changes during EVT, irrespective of the sensor position. It is likely that even with temporal sensor application, a significant proportion of the received NIRS signal was influenced by oxygenation of surrounding tissues.

Optimal management of asymptomatic carotid stenosis in 2021: the jury is still out. An international, multispecialty, expert review and position statement.

The recommendations of international guidelines for the management of asymptomatic carotid stenosis (ACS) often vary considerably and extend from a conservative approach with risk factor modification and best medical treatment (BMT) alone, to a more aggressive approach with a carotid intervention plus BMT. The aim of the current multispecialty position statement was to reconcile the conflicting views on the topic. A literature review was performed with a focus on data from recent studies. Several clinical and imaging high-risk features have been identified that are associated with an increased long-term ipsilateral ischemic stroke risk in patients with ACS. Such high-risk clinical/imaging features include intraplaque hemorrhage, impaired cerebrovascular reserve, carotid plaque echolucency/ulceration/ neovascularization, a lipid-rich necrotic core, a thin or ruptured fibrous cap, silent brain infarction, a contralateral transient ischemic attack/stroke episode, male patients <75 years and microembolic signals on transcranial Doppler. There is growing evidence that 80-99% ACS indicate a higher stroke risk than 50-79% stenoses. Although aggressive risk factor control and BMT should be implemented in all ACS patients, several high-risk features that may increase the risk of a future cerebrovascular event are now documented. Consequently, some guidelines recommend a prophylactic carotid intervention in high-risk patients to prevent future cerebrovascular events. Until the results of the much-anticipated randomized controlled trials emerge, the jury is still out regarding the optimal management of ACS patients.

Sensitivity of prehospital stroke scales for different intracranial large vessel occlusion locations.

INTRODUCTION: Prehospital stroke scales have been proposed to identify stroke patients with a large vessel occlusion to allow direct transport to an intervention centre capable of endovascular treatment (EVT). It is unclear whether these scales are able to detect not only proximal, but also more distal treatable occlusions. Our aim was to assess the sensitivity of prehospital stroke scales for different EVT-eligible occlusion locations in the anterior circulation. PATIENTS AND METHODS: The MR CLEAN Registry is a prospective, observational study in all centres that perform EVT in the Netherlands. We included adult patients with an anterior circulation stroke treated between March 2014 and November 2017. We used National Institutes of Health Stroke Scale scores at admission to reconstruct previously published prehospital stroke scales. We compared the sensitivity of each scale for different occlusion locations. Occlusions were assessed with CT angiography by an imaging core laboratory blinded to clinical findings. RESULTS: We included 3021 patients for the analysis of 14 scales. All scales had the highest sensitivity to detect internal carotid artery terminus occlusions (ranging from 0.21 to 0.97) and lowest for occlusions of the M2 segment (0.08 to 0.84, p-values < 0.001).Discussion and conclusion: Although prehospital stroke scales are generally sensitive for proximal large vessel occlusions, they are less sensitive to detect more distal occlusions.

Relationship between haemodynamic impairment and collateral blood flow in carotid artery disease.

Collateral blood flow plays a pivotal role in steno-occlusive internal carotid artery (ICA) disease to prevent irreversible ischaemic damage. Our aim was to investigate the effect of carotid artery disease upon cerebral perfusion and cerebrovascular reactivity and whether haemodynamic impairment is influenced at brain tissue level by the existence of primary and/or secondary collateral. Eighty-eight patients with steno-occlusive ICA disease and 29 healthy controls underwent MR examination. The presence of collaterals was determined with time-of-flight, two-dimensional phase contrast MRA and territorial arterial spin labeling (ASL) imaging. Cerebral blood flow and cerebrovascular reactivity were assessed with ASL before and after acetazolamide. Cerebral haemodynamics were normal in asymptomatic ICA stenosis patients, as opposed to patients with ICA occlusion, in whom the haemodynamics in both hemispheres were compromised. Haemodynamic impairment in the affected brain region was always present in symptomatic patients. The degree of collateral blood flow was inversely correlated with haemodynamic impairment. Recruitment of secondary collaterals only occurred in symptomatic ICA occlusion patients. In conclusion, both CBF and cerebrovascular reactivity were found to be reduced in symptomatic patients with steno-occlusive ICA disease. The presence of collateral flow is associated with further haemodynamic impairment. Recruitment of secondary collaterals is associated with severe haemodynamic impairment.