Quality review and education as method of improving guideline adherence for medication prescription and outcomes among vascular interventionalists performing non-cardiac vascular surgeries

Background: Medical management of patients undergoing non-cardiac vascular procedures often sub-optimally follow evidence based guidelines. We hypothesized that feedback to practitioners in regards to outcomes and medications prescribed would improve care. Methods: With conversion to new database in 2015 that allowed for more comprehensive tracking of vascular surgery outcomes, a decision was made to share these data with practitioners on regular basis as well as relay medications prescribed at discharge. Carotid and abdominal aortic surgeries were evaluated. The most frequent format for presentation of data was vascular morbidity and mortality conference. Medications included in presentations were antiplatelet and statin therapies. Comparisons were made between adherence to guideline based therapies 2 years before and 2 years after new database implementation. ACE inhibitor/aldosterone receptor blocker (ARB) therapy prescribing data were not included in these presentations. SAS Enterprise Guide 7.1 and R 3.6.1 software used for analysis. Results: 826 patients were evaluated. 400 patients were in pre new database implementation and 426 were included after implementation. No significant difference found with prescribing of ACE inhibitors/ARB, changing only from 47 to 48%. There was difference with univariate analysis of antiplatelet and statin prescribing. Antiplatelet prescribing improved from 89 to 93%, Odds Ratio (OR) = 1.7 (95% confidence interval, 1-2.8) and statin prescribing improved from 74 to 86%, OR= 2.1 (95% confidence interval, 1.5-3). Access site and bleeding complications also demonstrated improvement. See Figure. Conclusion: Regular feedback to vascular practitioners improves adherence to guideline based therapies and can improve surgical outcomes

Solving the Interpretational-Confounding and Interpretational-Ambiguity Problems of Formative Construct Modeling in Behavioral Research: Proposing a Two-Stage Fixed-Weight Redundancy Approach

Recently, information systems research has devoted increasing attention to formative measurements. However, current approaches to modeling formative constructs have potential validity problems and thus limited applicability. Here, we highlight two major problems in formative measurement—interpretational confounding and interpretational ambiguity—and propose a novel resolution. Interpretational confounding occurs when using the traditional free-estimation approach, because the weights of different formative indicators vary as the dependent variable changes, resulting in the distortion of the measurement weights of the focal formative construct and thus jeopardizing the generalizability of empirical tests. Another way to alleviate the interpretational-confounding issue is to include the multiple indicators multiple causes (MIMIC) construct in the path model (i.e., MIMIC-path). Unfortunately, this method has led to the second major problem of interpretational ambiguity, the existence of more than one potential explanation of the formative model. More specifically, reflective indicators in the MIMIC model can be viewed as (1) indicators of the MIMIC construct, (2) dependent variables of the formative construct, or (3) indicators of a reflective construct affected by independent variables (formative indicators). To resolve these issues, we propose a two-stage fixed-weight redundancy model (FWRM) approach. We demonstrate the applicability of the FWRM approach with a set of survey data. We conducted a simulation study evaluating the FWRM approach by comparing it with the commonly used free-estimation and MIMIC-path methods. The results indicate that our FWRM approach can indeed improve the validity of formative construct modeling by mitigating confounding and ambiguity issues

Shifts in stream hydrochemistry in responses to typhoon and non-typhoon precipitation

Climate change is projected to increase the intensity and frequency of extreme climatic events such as tropical cyclones. However, few studies have examined the responses of hydrochemical processes to climate extremes. To fill this knowledge gap, we compared the relationship between stream discharge and ion input–output budget during typhoon and non-typhoon periods in four subtropical mountain watersheds with different levels of agricultural land cover in northern Taiwan. The results indicated that the high predictability of ion input–output budgets using stream discharge during the non-typhoon period largely disappeared during the typhoon periods. For ions such as Na+, NH+4, and PO3−4, the typhoon period and non-typhoon period exhibited opposite discharge–budget relationships. In other cases, the discharge–budget relationship was driven by the typhoon period, which consisted of only 7 % of the total time period. The striking differences in the discharge–ion budget relationship between the two periods likely resulted from differences in the relative contributions of surface runoff, subsurface runoff and groundwater, which had different chemical compositions, to stream discharge between the two periods. Watersheds with a 17–22 % tea plantation cover showed large increases in NO−3 export with increases in stream discharge. In contrast, watersheds with 93–99 % forest cover showed very mild or no increases in NO−3 export with increases in discharge and very low levels of NO−3 export even during typhoon storms. The results suggest that even mild disruption of the natural vegetation could largely alter hydrochemical processes. Our study clearly illustrates significant shifts in hydrochemical responses between regular and typhoon precipitation. We propose that hydrological models should separate hydrochemical processes into regular and extreme conditions to better capture the whole spectrum of hydrochemical responses to a variety of climate conditions

TCT-804 Outcomes of Trans-Carotid TAVR in a high-Volume Center

Background Although the preferred route for transcatheter aortic valve replacement is through the femoral artery, alternatives remain necessary for patients with obstructive iliofemoral disease. Our valve team has developed a large experience using the carotid artery as a primary alternative vascular access approach for transcatheter aortic valve replacement (TAVR). We aim to compare short-term outcomes by access route in a single-center, high-volume, transcarotid (TC) TAVR program. Methods All patients undergoing TAVR between September 2012 and September 2018 were included in the study. Baseline demographics and outcomes were obtained from data our institution submitted in compliance with TVT (Transcatheter Valve Therapy) reporting and are supplemented by individual chart review. Results Overall, 1,153 commercial TAVR procedures were completed during the study period. Of these, 976 (85%) were transfemoral (TF), 105 (9%) were TC, and 72 (6%) were other (53 transapical, 14 transaxillary, 5 transaortic). TF patients had lower Society of Thoracic Surgeons (STS) scores (6.0% vs. 7.1% vs. 8.3%), peripheral vascular disease (24% vs. 88% vs. 72%), and cerebral vascular disease (11% vs. 17% vs. 32%) compared with TC and other patients, respectively (p \u3c 0.001). Combined in-hospital and 30-day mortality was 2.6% for the TF cohort versus 3.8% for TC (p = 0.36) and 13.9% for other (p \u3c 0.001). The stroke rate at 30 days was 3.7% for TF versus 3.8% for TC and 4.2% for other access routes (p = 0.98) (Table). Conclusion TAVR can be safely performed from the TC access route at a high-volume center with similar in-hospital and 30-day mortality and stroke rates compared with TF patients. Mortality was significantly increased, however, in patients treated with other alternative access routes

Scalable photonic sources using two-dimensional lead halide perovskite superlattices

Miniaturized photonic sources based on semiconducting two-dimensional (2D) materials offer new technological opportunities beyond the modern III-V platforms. For example, the quantum-confined 2D electronic structure aligns the exciton transition dipole moment parallel to the surface plane, thereby outcoupling more light to air which gives rise to high-efficiency quantum optics and electroluminescent devices. It requires scalable materials and processes to create the decoupled multi-quantum-well superlattices, in which individual 2D material layers are isolated by atomically thin quantum barriers. Here, we report decoupled multi-quantum-well superlattices comprised of the colloidal quantum wells of lead halide perovskites, with unprecedentedly ultrathin quantum barriers that screen interlayer interactions within the range of 6.5 Å. Crystallographic and 2D k-space spectroscopic analysis reveals that the transition dipole moment orientation of bright excitons in the superlattices is predominantly in-plane and independent of stacking layer and quantum barrier thickness, confirming interlayer decoupling