Recent advances in modeling oxygen supply to cortical brain tissue have begun to elucidate the functional mechanisms of neurovascular coupling. While the principal mechanisms of blood flow regulation ...after neuronal firing are generally known, mechanistic hemodynamic simulations cannot yet pinpoint the exact spatial and temporal coordination between the network of arteries, arterioles, capillaries and veins for the entire brain. Because of the potential significance of blood flow and oxygen supply simulations for illuminating spatiotemporal regulation inside the cortical microanatomy, there is a need to create mathematical models of the entire cerebral circulation with realistic anatomical detail. Our hypothesis is that an anatomically accurate reconstruction of the cerebrocirculatory architecture will inform about possible regulatory mechanisms of the neurovascular interface. In this article, we introduce large-scale networks of the murine cerebral circulation spanning the Circle of Willis, main cerebral arteries connected to the pial network down to the microcirculation in the capillary bed. Several multiscale models were generated from state-of-the-art neuroimaging data. Using a vascular network construction algorithm, the entire circulation of the middle cerebral artery was synthesized. Blood flow simulations indicate a consistent trend of higher hematocrit in deeper cortical layers, while surface layers with shorter vascular path lengths seem to carry comparatively lower red blood cell (RBC) concentrations. Moreover, the variability of RBC flux decreases with cortical depth. These results support the notion that plasma skimming serves a self-regulating function for maintaining uniform oxygen perfusion to neurons irrespective of their location in the blood supply hierarchy. Our computations also demonstrate the practicality of simulating blood flow for large portions of the mouse brain with existing computer resources. The efficient simulation of blood flow throughout the entire middle cerebral artery (MCA) territory is a promising milestone towards the final aim of predicting blood flow patterns for the entire brain.
Objectives:
To quantify parental acceptance of the COVID-19 vaccine and assess the vaccine hesitancy (VH) for COVID-19 vs. childhood vaccines.
Methods:
Eight vaccine hesitancy scale (VHS) items, ...adopted from WHO's Strategic Advisory Group of Immunization (SAGE), were used to assess VH for COVID-19 vaccine vs. routine childhood vaccines. We distributed the online survey to parents with the commence of the national childhood COVID-19 vaccination program in Saudi Arabia.
Results:
Among 3,167 parents, 47.6% are decided to vaccinate their children against COVID-19. The most common reasons for refusal were inadequate safety information (69%) and worry about side effects (60.6%). Parents have a significantly greater positive attitudes toward children's routine vaccines vs. the COVID-19 vaccine, with higher mean VHS (±SD) = 2.98 ± 0.58 vs. 2.63 ± 0.73, respectively (
p
-value < 0.001). Parents agreed more that routine childhood vaccines are more essential and effective as compared to the COVID-19 vaccine (Cohen's D: 0.946, and 0.826, consecutively;
T
-test
p
-value < 0.00). There is more parental anxiety about serious side effects of the COVID-19 vaccine vs. routine childhood vaccines (Cohen's
D
= 0.706,
p
-value < 0.001). Parents who relied on the Ministry of Health information were more predicted (OR = 1.28,
p
-value = 0.035) to intend to vaccinate as opposed to those who used the WHO website (OR = 0.47, −53%,
p
-value < 0.001). In a multivariate logistic regression analysis, the factors associated with intention to vaccinate children were parents who received COVID-19 vaccine, older parents, having children aged 12–18, and parents with lower education levels.
Conclusions:
Significant proportion of parents are hesitant about the COVID-19 vaccine because they are less confident in its effectiveness, safety, and whether it is essential for their children. Relying on the national official healthcare authority's website for the source of information was associated with increased acceptance of childhood COVID-19 vaccination. As parental intention to vaccinate children against COVID-19 is suboptimal, healthcare authorities could boost vaccine uptake by campaigns targeting hesitant parents.
This study aimed to identify coronavirus disease 2019 (COVID-19) vaccine perception, acceptance, confidence, hesitancy, and barriers among health care workers (HCWs). An online national ...cross-sectional pilot-validated questionnaire was self-administered by HCWs in Saudi Arabia, which is a nation with MERS-CoV experience. The main outcome variable was HCWs' acceptance of COVID-19 vaccine candidates. The factors associated with vaccination acceptance were identified through a logistic regression analysis, and the level of anxiety was measured using a validated instrument to measure general anxiety levels. Out of the 1512 HCWs who completed the study questionnaire-of which 62.4% were women-70% were willing to receive COVID-19 vaccines. A logistic regression analysis revealed that male HCWs (ORa = 1.551, 95% CI: 1.122-2.144), HCWs who believe in vaccine safety (ORa = 2.151; 95% CI: 1.708-2.708), HCWs who believe that COVID vaccines are the most likely way to stop the pandemic (ORa = 1.539; 95% CI: 1.259-1.881), and HCWs who rely on the Centers for Disease Control and Prevention website for COVID 19 updates (ORa = 1.505, 95% CI: 1.125-2.013) were significantly associated with reporting a willingness to be vaccinated. However, HCWs who believed that the vaccines were rushed without evidence-informed testing were found to be 60% less inclined to accept COVID-19 vaccines (ORa = 0.394, 95% CI: 0.298-0.522). Most HCWs are willing to receive COVID-19 vaccines once they are available; the satisfactoriness of COVID-19 vaccination among HCWs is crucial because health professionals' knowledge and confidence toward vaccines are important determining factors for not only their own vaccine acceptance but also recommendation for such vaccines to their patients.
Departures of normal blood flow and metabolite distribution from the cerebral microvasculature into neuronal tissue have been implicated with age-related neurodegeneration. Mathematical models ...informed by spatially and temporally distributed neuroimage data are becoming instrumental for reconstructing a coherent picture of normal and pathological oxygen delivery throughout the brain. Unfortunately, current mathematical models of cerebral blood flow and oxygen exchange become excessively large in size. They further suffer from boundary effects due to incomplete or physiologically inaccurate computational domains, numerical instabilities due to enormous length scale differences, and convergence problems associated with condition number deterioration at fine mesh resolutions. Our proposed simple finite volume discretization scheme for blood and oxygen microperfusion simulations does not require expensive mesh generation leading to the critical benefit that it drastically reduces matrix size and bandwidth of the coupled oxygen transfer problem. The compact problem formulation yields rapid and stable convergence. Moreover, boundary effects can effectively be suppressed by generating very large replica of the cortical microcirculation in silico using an image-based cerebrovascular network synthesis algorithm, so that boundaries of the perfusion simulations are far removed from the regions of interest. Massive simulations over sizeable portions of the cortex with feature resolution down to the micron scale become tractable with even modest computer resources. The feasibility and accuracy of the novel method is demonstrated and validated with in vivo oxygen perfusion data in cohorts of young and aged mice. Our oxygen exchange simulations quantify steep gradients near penetrating blood vessels and point towards pathological changes that might cause neurodegeneration in aged brains. This research aims to explain mechanistic interactions between anatomical structures and how they might change in diseases or with age. Rigorous quantification of age-related changes is of significant interest because it might aide in the search for imaging biomarkers for dementia and Alzheimer's disease.
Background
A venous thromboembolism (VTE) bundle was launched in 2016 at the University of Illinois Hospital aiming to reduce the rate of VTE in the neurosurgical ICU. Main elements of the bundle ...included correct and early use of intermittent pneumatic compression and subcutaneous heparin.
Methods
Patients with SAH were retrospectively identified from 2014 until 2018. VTE events were diagnosed using twice weekly lower-extremity venous Duplex ultrasound and chest computerized tomography when appropriate.
Results
A total of 133 patients was included in each group. The incidence of VTE was not significantly different before and after the bundle (15% vs. 12%, p = 0.47). No difference was found regarding new episode of intracranial hemorrhage secondary to SQH (1.5% vs. 2.1%, p = 0.65). Multivariate analysis demonstrated that longer ICU LOS, higher Caprini score, and presence of baseline lung diseases were associated with VTE development.
Conclusions
With a median Caprini score of 9, our patient population was found to be at high risk for developing VTE. The implementation of the VTE bundle did not significantly reduce the rate of VTE in patients with non-traumatic SAH at UIH.
Background: The popularity of e-cigarettes is increasing rapidly worldwide and advertisements for such products are becoming ubiquitous in the media. Health concerns and smoking cessation are the ...most commonly reported reasons for traditional tobacco smokers to shift to e-cigarettes. As a result, the global market for e-cigarettes is on the rise. However, they are still a potential cause for many diseases. Methods: This is a cross-sectional study carried out at Qassim University in Buraydah, Saudi Arabia. A prevalidated questionnaire was distributed to medical students in April 2018 to evaluate the experience, knowledge, and awareness of e-cigarettes among the participants. Results: About one in ten students confirmed having smoked an e-cigarette. There was no significant relationship between e-cigarette users and demographic factors, such as gender, academic level, or age. However, the study showed a significant association between e-cigarette smoking and having an e-cigarette smoker among family members or friends. Most students 71.9% were not sure whether e-cigarettes were approved by the Food and Drug Administration (FDA) for smoking cessation. Only 23.3% of those surveyed believed that e-cigarettes can help in smoking cessation, whereas only 11% said that they would recommend it for a patient. On the contrary, 49.6% agreed that e-cigarettes are addictive. In response to another question, 92% reported receiving no education in medical school about e-cigarettes. Conclusion: Our study showed that medical students lacked knowledge about e-cigarettes. Therefore, more studies are needed to raise awareness about e-cigarettes, especially since the habit of using e-cigarettes is invading our society.
Abstract
Recent studies have shown that mental script-based rehearsal and simulation-based training improve the transfer of surgical skills in various medical disciplines. Despite significant ...advances in technology and intraoperative techniques over the last several decades, surgical skills training on neurosurgical operations still carries significant risk of serious morbidity or mortality. Potentially avoidable technical errors are well recognized as contributing to poor surgical outcome. Surgical education is undergoing overwhelming change, as a result of the reduction of work hours and current trends focusing on patient safety and linking reimbursement with clinical outcomes. Thus, there is a need for adjunctive means for neurosurgical training, which is a recent advancement in simulation technology. ImmersiveTouch is an augmented reality system that integrates a haptic device and a high-resolution stereoscopic display. This simulation platform uses multiple sensory modalities, re-creating many of the environmental cues experienced during an actual procedure. Modules available include ventriculostomy, bone drilling, percutaneous trigeminal rhizotomy, and simulated spinal modules such as pedicle screw placement, vertebroplasty, and lumbar puncture. We present our experience with the development of such augmented reality neurosurgical modules and the feedback from neurosurgical residents.
Background: As the COVID-19 Delta variant has spread across the globe, healthcare workers’ (HCWs) knowledge, worries, and vaccine booster acceptance should be assessed. Methods: Online questionnaires ...aimed at HCWs in Saudi Arabia were distributed between 9 and 12 August 2021, aiming to evaluate HCWs’ perceptions and worries about the Delta variant as well as their feelings about receiving a booster-vaccine. Results: A total of 1279 HCWs participated, with 51.1% being physicians and 41.7% nurses. 92.5% were aware of the emergence of the Delta variant. Still, only 28.7% were found to have sufficient knowledge of the variant, and their level of worry about it was higher than their level of worry about the Alpha variant (2.32/5 versus 1.79/5). The main information sources cited by the participants were social media (50.5%), while 30.5% used scientific journals. Overall, 55.3% were willing to receive a vaccine booster, while one third would have preferred to receive a new mRNA vaccine specifically developed for the Delta variant. Factors associated with vaccine booster acceptance were receiving both vaccination doses (p = 0.008), believing that the Pfizer-BioNTech BNT162b2 vaccine is effective against variants (p < 0.001), and agreement that mixing/matching vaccines is effective against variants (p < 0.001). Conclusions: A high percentage of HCWs were aware of the Delta variant, but only a small fraction had decent quality of knowledge about it. The participants exhibited high worry levels and showed a modest acceptance of receiving a vaccine booster dose. These results should encourage public health officials to scale up educational efforts to disseminate reliable information about the different variants and provide recommendations about receiving a vaccine booster. Further research on methods to alleviate HCWs’ worries about emerging variants is warranted.
Background: Monkeypox virus re-surged in May 2022 as a new potential global health threat, with outbreaks bursting in multiple countries across different continents. This study was conducted in Saudi ...Arabia during the first month following the WHO announcement of the Monkeypox outbreak, to assess healthcare workers (HCWs) perceptions of, worries concerning, and vaccine acceptance for, Monkeypox, in light of the resolving COVID-19 pandemic. Methods: A national cross-sectional survey was conducted between 27 May and 10 June 2022, in Saudi Arabia. Data were collected on: HCWs’ sociodemographic and job-related characteristics; COVID-19 infection status; and worries concerning Monkeypox, compared to COVID-19 and its sources; as well as their perceptions and awareness of, and advocacy for, supporting Monkeypox vaccination. Results: A total of 1130 HCWs completed the survey, of which 41.6% have already developed COVID-19. However, 56.5% were more concerned about COVID-19 compared to Monkeypox, while the rest were more worried about Monkeypox disease. The main cause for concern among 68.8% of the participants was the development of another worldwide pandemic, post-COVID-19, followed by their concern of either themselves or their families contracting the infection (49.6%). Most HCWs (60%) rated their level of self-awareness of Monkeypox disease as moderate to high. Males, and those who had previously developed COVID-19, were significantly less likely to worry about Monkeypox. The worry about Monkeypox developing into a pandemic, and the perception of Monkeypox being a severe disease, correlated significantly positively with the odds of high worry concerning the disease. The major predictors of participants’ advocacy for vaccination against Monkeypox disease were: those who had developed COVID-19 previously; and those who supported tighter infection control measures (than those currently used) to combat the disease. A total of 74.2% of the surveyed HCWs perceived that they needed to read more about Monkeypox disease. Conclusions: Approximately half of the HCWs in this study were more concerned about Monkeypox disease than COVID-19, particularly regarding its possible progression into a new pandemic, during the first month following the WHO’s Monkeypox international alert. In addition, the majority of participants were in favor of applying tighter infection prevention measures to combat the disease. The current study highlights areas requiring attention for healthcare administrators regarding HCWs’ perceptions and preparedness for Monkeypox, especially in the event of a local or international pandemic.
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