2,896 research outputs found

    Contrast-enhanced micro-CT imaging in murine carotid arteries : a new protocol for computing wall shear stress

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    Background: Wall shear stress (WSS) is involved in the pathophysiology of atherosclerosis. The correlation between WSS and atherosclerosis can be investigated over time using a WSS-manipulated atherosclerotic mouse model. To determine WSS in vivo, detailed 3D geometry of the vessel network is required. However, a protocol to reconstruct 3D murine vasculature using this animal model is lacking. In this project, we evaluated the adequacy of eXIA 160, a small animal contrast agent, for assessing murine vascular network on micro-CT. Also, a protocol was established for vessel geometry segmentation and WSS analysis. Methods: A tapering cast was placed around the right common carotid artery (RCCA) of ApoE(-/-) mice (n = 8). Contrast-enhanced micro-CT was performed using eXIA 160. An innovative local threshold-based segmentation procedure was implemented to reconstruct 3D geometry of the RCCA. The reconstructed RCCA was compared to the vessel geometry using a global threshold-based segmentation method. Computational fluid dynamics was applied to compute the velocity field and WSS distribution along the RCCA. Results: eXIA 160-enhanced micro-CT allowed clear visualization and assessment of the RCCA in all eight animals. No adverse biological effects were observed from the use of eXIA 160. Segmentation using local threshold values generated more accurate RCCA geometry than the global threshold-based approach. Mouse-specific velocity data and the RCCA geometry generated 3D WSS maps with high resolution, enabling quantitative analysis of WSS. In all animals, we observed low WSS upstream of the cast. Downstream of the cast, asymmetric WSS patterns were revealed with variation in size and location between animals. Conclusions: eXIA 160 provided good contrast to reconstruct 3D vessel geometry and determine WSS patterns in the RCCA of the atherosclerotic mouse model. We established a novel local threshold-based segmentation protocol for RCCA reconstruction and WSS computation. The observed differences between animals indicate the necessity to use mouse-specific data for WSS analysis. For our future work, our protocol makes it possible to study in vivo WSS longitudinally over a growing plaque

    Height is a predictor of hamstring tendon length and ACL graft characteristics in adolescents

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    BackgroundKnowing the potential hamstring tendon length is relevant for planning ligament reconstructions in children and adolescents, as it is not uncommon to encounter small hamstring tendons intraoperatively. The aim of this study is to predict semitendinosus and gracilis tendon length based on anthropometric values in children and adolescents. The secondary aim is to analyse hamstring tendon autograft characteristics in a closed socket anterior cruciate ligament reconstructions and to evaluate the relationship with anthropometric variables. The hypothesis of this study was that height is predictor of hamstring tendon length and thereby graft characteristics.MethodsThis observational study included two cohorts of adolescents undergoing ligament reconstructions between 2007–2014 and 2017–2020. Age, sex, height and weight were recorded preoperatively. Semitendinosus and gracilis tendon length and graft characteristics were measured intraoperatively. Regression analysis was performed on tendon length and anthropometric values. Subgroup analyses of the closed socket ACL reconstruction were performed and the relation between anthropometric values and graft characteristics were analysed.ResultsThe population consisted of 171 adolescents from 13 to 17 years of age, with a median age of 16 years [IQR 16–17]. The median semitendinosus tendon length was 29 cm [IQR 26–30] and gracilis tendon length was 27 cm [IQR 25–29]. Height was a significant predictor of semitendinosus and gracilis tendon length. Subgroup analysis of the closed socket ACL reconstructions showed that in 75% of the procedure, the semitendinosus tendon alone was sufficient to create a graft with a minimum diameter of 8.0 mm.ConclusionsHeight is a significant predictor of semitendinosus and gracilis tendon length in adolescents between 13 and 17 years of age and outcomes are similar to data in adults. In 75% of the closed socket ACL reconstructions, the semitendinosus tendon alone is sufficient to create an adequate graft with a minimum diameter of 8 mm. Additional use of the gracilis tendon is more often necessary in females and shorter patients

    The development of a glucose prediction model in critically ill patients

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    Purpose: The aim of the current study is to develop a prediction model for glucose levels applicable for all patients admitted to the ICU with an expected ICU stay of at least 24 h. This model will be incorporated in a closed-loop glucose system to continuously and automatically control glucose values. Methods: Data from a previous single-center randomized controlled study was used. All patients received a FreeStyle Navigator II subcutaneous CGM system from Abbott during their ICU stay. The total dataset was randomly divided into a training set and a validation set. A glucose prediction model was developed based on historical glucose data. Accuracy of the prediction model was determined using the Mean Squared Difference (MSD), the Mean Absolute Difference (MAD) and a Clarke Error Grid (CEG). Results: The dataset included 94 ICU patients with a total of 134,673 glucose measurements points that were used for modelling. MSD was 0.410 +/- 0.495 for the model, the MAD was 5.19 +/- 2.63 and in the CEG 99.8% of the data points were in the clinically acceptable regions. Conclusion: In this study a glucose prediction model for ICU patients is developed. This study shows that it is possible to accurately predict a patient's glucose 30 min ahead based on historical glucose data. This is the first step in the development of a closed-loop glucose system. (C) 2021 Elsevier B.V. All rights reserved

    Advance Care Planning in the Netherlands

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    The Dutch health care system fosters a strong public health sector offering accessible generalist care including generalist palliative care. General practitioners are well positioned to conduct ACP, for example, to continue or initiate conversations after hospitalization. However, research shows that ACP conversations are often ad hoc and in frail patients, ACP is often only initiated when admitted to a nursing home by elderly care physicians who are on the staff. Tools that raise awareness of triggers to initiate ACP, screening tools, information brochures, checklists and training have been developed and implemented with funding by national programs which currently focus on implementation projects rather than or in addition to, research. The programs commonly require educational deliverables, patient and public involvement and addressing diversity in patient groups. A major challenge is how to implement ACP systematically and continuously across sectors and disciplines in a way that supports a proactive yet person-centered approach rather than an approach with an exclusive focus on medical procedures. Digital solutions can support continuity of care and communication about care plans. Solutions should fit a culture that prefers trust-based, informal deliberative approaches. This may be supported by involving disciplines other than medicine, such as nursing and spiritual caregiving, and public health approaches.</p

    Pedi-IKDC or KOOS-child: Which questionnaire should be used in children with knee disorders?

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    Background: The Pedi International Knee Documentation Committee (IKDC) and Knee Injury and Osteoarthritis Outcome Score (KOOS) child are validated questionnaires for children with knee disorders. The aim of this study was to translate these questionnaires in Dutch and to recommend which questionnaires should - based on their psychometric properties - be used in clinical practice. Methods: The English Pedi-IKDC and KOOS-Child were translated by the forward-backward procedure. Subsequently, content validity of the Pedi-IKDC and KOOS-Child was evaluated by both patients (n = 18) and experts (n = 18). To evaluate construct validity and interpretability participants with knee disorders (n = 100) completed the Numeric Rating Scale Pain, Lysholm Knee Scoring Scale, EuroQol-5 Dimension, Pedi-IKDC and KOOS-Child at baseline. Participants completed the anchor question, Pedi-IKDC and KOOS-child two weeks (n = 54) and one year (n = 71) after baseline, for evaluating the test-retest reliability and responsiveness. Psychometric properties were interpreted following the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) criteria. Results: The Pedi-IKDC showed adequate test-retest reliability (intraclass correlation coefficient (ICC) 0.9; standard error of measurement (SEM) 8.6; smallest detectable change (SDC) 23.8), adequate content validity (> 75% relevant), adequate construct validity (75% confirmed hypotheses), low floor or ceiling effects (scores between 5 and 95) and adequate responsiveness (> 75% confirmed hypotheses). The KOOS-Child showed an adequate test-retest reliability (ICC 0.8-0.9; SEM 8.9-16.9; SDC 24.7-46.9), adequate content validity (> 75% relevant, except KOOS-Child subscale ADL), adequate construct validity (75% confirmed hypotheses), low floor and ceiling effects (scores between 5 and 95, except KOOS-Child subscale activities of daily living and Sport/play) and moderate responsiveness (40% confirmed hypotheses). Conclusions: The Pedi IKDC showed better psychometric properties than the KOOS-Child and should therefore be used in children with knee disorders

    Factors related to establishing a comfort care goal in nursing home patients with dementia : a cohort study among family and professional caregivers

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    Background: Many people with dementia die in long-term care settings. These patients may benefit from a palliative care goal, focused on comfort. Admission may be a good time to revisit or develop care plans. Objective: To describe care goals in nursing home patients with dementia and factors associated with establishing a comfort care goal. Design: We used generalized estimating equation regression analyses for baseline analyses and multinomial logistic regression analyses for longitudinal analyses. Setting: Prospective data collection in 28 Dutch facilities, mostly nursing homes (2007-2010; Dutch End of Life in Dementia study, DEOLD). Results: Eight weeks after admission (baseline), 56.7% of 326 patients had a comfort care goal. At death, 89.5% had a comfort care goal. Adjusted for illness severity, patients with a baseline comfort care goal were more likely to have a religious affiliation, to be less competent to make decisions, and to have a short survival prediction. Their families were less likely to prefer life-prolongation and more likely to be satisfied with family-physician communication. Compared with patients with a comfort care goal established later during their stay, patients with a baseline comfort care goal also more frequently had a more highly educated family member. Conclusions: Initially, over half of the patients had a care goal focused on comfort, increasing to the large majority of the patients at death. Optimizing patient-family-physician communication upon admission may support the early establishing of a comfort care goal. Patient condition and family views play a role, and physicians should be aware that religious affiliation and education may also affect the (timing of) setting a comfort care goal
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