Impact of COVID-19 on patients undergoing scheduled procedures for chronic venous disease.

OBJECTIVE: The COVID-19 pandemic has drastically altered the medical landscape. Various strategies have been employed to preserve hospital beds, personal protective equipment, and other resources to accommodate the surges of COVID-19 positive patients, hospital overcapacities, and staffing shortages. This has had a dramatic effect on vascular surgical practice. The objective of this study is to analyze the impact of the COVID-19 pandemic on surgical delays and adverse outcomes for patients with chronic venous disease scheduled to undergo elective operations. METHODS: The Vascular Surgery COVID-19 Collaborative (VASCC) was founded in March 2020 to evaluate the outcomes of patients with vascular disease whose operations were delayed. Modules were developed by vascular surgeon working groups and tested before implementation. A data analysis of outcomes of patients with chronic venous disease whose surgeries were postponed during the COVID-19 pandemic from March 2020 through February 2021 was performed for this study. RESULTS: A total of 150 patients from 12 institutions in the United States were included in the study. Indications for venous intervention were: 85.3% varicose veins, 10.7% varicose veins with venous ulceration, and 4.0% lipodermatosclerosis. One hundred two surgeries had successfully been completed at the time of data entry. The average length of the delay was 91 days, with a median of 78 days. Delays for venous ulceration procedures ranged from 38 to 208 days. No patients required an emergent intervention due to their venous disease, and no patients experienced major adverse events following their delayed surgeries. CONCLUSIONS: Interventions may be safely delayed for patients with venous disease requiring elective surgical intervention during the COVID-19 pandemic. This finding supports the American College of Surgeons' recommendations for the management of elective vascular surgical procedures. Office-based labs may be safe locations for continued treatment when resources are limited. Although the interventions can be safely postponed, the negative impact on quality of life warrants further investigation.

Building a vertically integrated genomic learning health system: The biobank at the Colorado Center for Personalized Medicine.

Precision medicine initiatives across the globe have led to a revolution of repositories linking large-scale genomic data with electronic health records, enabling genomic analyses across the entire phenome. Many of these initiatives focus solely on research insights, leading to limited direct benefit to patients. We describe the biobank at the Colorado Center for Personalized Medicine (CCPM Biobank) that was jointly developed by the University of Colorado Anschutz Medical Campus and UCHealth to serve as a unique, dual-purpose research and clinical resource accelerating personalized medicine. This living resource currently has more than 200,000 participants with ongoing recruitment. We highlight the clinical, laboratory, regulatory, and HIPAA-compliant informatics infrastructure along with our stakeholder engagement, consent, recontact, and participant engagement strategies. We characterize aspects of genetic and geographic diversity unique to the Rocky Mountain region, the primary catchment area for CCPM Biobank participants. We leverage linked health and demographic information of the CCPM Biobank participant population to demonstrate the utility of the CCPM Biobank to replicate complex trait associations in the first 33,674 genotyped individuals across multiple disease domains. Finally, we describe our current efforts toward return of clinical genetic test results, including high-impact pathogenic variants and pharmacogenetic information, and our broader goals as the CCPM Biobank continues to grow. Bringing clinical and research interests together fosters unique clinical and translational questions that can be addressed from the large EHR-linked CCPM Biobank resource within a HIPAA- and CLIA-certified environment.

Carotid Artery Operation Delay During the Covid-19 Pandemic: Results of a Multicenter International Study.

BACKGROUND: To measure the impact of the COVID-19 pandemic on the management of patients with carotid artery stenosis. METHODS: We prospectively collected data from 25 centers (19 centers in the United States and 6 centers internationally) on postponed carotid artery operations between March 2020 and January 2022. We describe the characteristics of these patients and their planned operations, along with outcomes including mortality and neurological deterioration during the period of operative delay due to the COVID-19 pandemic. RESULTS: A total of 1,220 vascular operations were postponed during the pandemic, of them 96 patients presented with significant carotid stenosis (median stenosis of 71%; interquartile range; 70-80) and 80% of them were planned for carotid endarterectomy. Most patients were asymptomatic (69%), and 31% of patients were symptomatic (16% of patients had a stroke, 15% of patients had a transient ischemic attack, and 1% of patients experienced amaurosis fugax). The median length of surgical delay was 71 days (interquartile range: 45.5, 115.5). At the data entry time, 62% of patients had their carotid operations postponed and successfully completed. Most postponements (72%) were due to institutional policies aimed at resource conservation. During the delay, no patient decompensated or required an urgent operation. A total of 5 patients (5%) with carotid stenosis died while awaiting operations due to COVID-19. CONCLUSIONS: Our study of a cohort of patients with carotid artery stenosis who underwent a median delay of 71 days during the COVID-19 pandemic showed a disparate operation delay between US regions and internationally, most postponements were due to hospital policy, and none of the patients deteriorated or required an emergency surgery during the delay.

A primer on cohort studies in vascular surgery research.

Vascular research questions can be answered using various study designs. Observational studies are used frequently to address a wide range of clinical questions when randomized clinical trials are not feasible or practical. One of the powerful vascular research tools is the cohort study. The cohort study is a reliable observational study design in which individuals who share a common characteristic (a cohort) are followed over time and their outcomes are assessed at various intervals. This review focuses on the essential characteristics, design, implementation, bias, validity, and clinical significance of cohort studies and provides illustrative examples. A cohort study can be either a prospective or a retrospective study, depending on whether the outcome occurred before or after the enrollment of the cohort. Each type has its advantages and disadvantages. Confounding, selection, and information biases can all occur in cohort studies. Applications of the cohort study design include studying the natural history of a disease, describing a condition's frequency, and investigating multiple outcomes simultaneously.

Association of Virtual Surgical Planning With External Incisions in Complex Maxillectomy Reconstruction.

Importance: Maxillectomy can commonly be performed through a transoral approach, but maxillectomy defect reconstruction can be difficult to precisely design, contour, and inset through this approach. Objective: To evaluate whether the use of virtual surgical planning (VSP) and 3-dimensional (3-D) modeling is associated with a decrease in the requirement of lateral rhinotomy (LR) for patients undergoing total and partial maxillectomy reconstruction. Design, Setting, and Participants: This retrospective cohort study was conducted among patients undergoing subtotal or total maxillectomy with microvascular free flap reconstruction with or without VSP and 3-D modeling at a single tertiary care academic medical center between January 1, 2008, and October 3, 2019. Interventions: Maxillectomy and free flap reconstruction with or without VSP. Main Outcomes and Measures: Necessity of LR or other external incision for contouring, placement, and fixation of reconstruction as well as surgical complications. Results: Fifteen patients (12 men [80%]; mean age, 64 years) underwent maxillectomy with free flap reconstruction without VSP. Eight patients (53%) in this group underwent total maxillectomy, and 4 patients in this group (27%) underwent partial maxillectomy. Twenty-three patients (18 men [78%]; mean age, 58 years) underwent maxillectomy with free flap reconstruction and VSP and 3-D modeling. Twelve of these patients (52%) underwent total maxillectomy, and 11 (48%) underwent partial maxillectomy. Lateral rhinotomy was necessary for 1 patient (4%) in the VSP group vs 12 patients (80%; 95% CI, 54%-98%) in the pre-VSP group. There were no LR complications in the VSP group vs 6 in the pre-VSP group. Among both groups, 14 patients underwent fibula free flap, 22 patients underwent subscapular system free flap, and 2 patients underwent cutaneous or osteocutaneous radial forearm free flap. There were no flap failures in the LR group and 1 flap failure in the group without LR. Conclusions and Relevance: This cohort study suggests that the use of VSP and 3-D modeling for maxillectomy reconstruction is associated the a decrease in the need for external incisions without compromising reconstructive flap utility.

Thermodynamic examination of pH and magnesium effect on U6 RNA internal loop.

U6 RNA contains a 1 × 2-nt internal loop that folds and unfold during spliceosomal assembly and activation. The 1 × 2 loop consists of a C67•A79 base pair that forms an additional hydrogen bond upon protonation, C67•A+79, and uracil (U80) that coordinates the catalytically essential magnesium ions. We designed a series of RNA and DNA constructs with a 1 × 2 loop sequence contained in the ISL, and its modifications, to measure the thermodynamic effects of protonation and magnesium binding using UV-visible thermal denaturation experiments. We show that the wild-type RNA construct gains 0.43 kcal/mol in 1 M KCl upon lowering the pH from 7.5 to 5.5; the presence of magnesium ions increases its stability by 2.17 kcal/mol at pH 7.5 over 1 M KCl. Modifications of the helix closing base pairs from C-G to U•G causes a loss in protonation-dependent stability and a decrease in stability in the presence of magnesium ions, especially in the C68U construct. A79G single-nucleotide bulge loop construct showed the largest gain in stability in the presence of magnesium ions. The DNA wild-type construct shows a smaller effect on stability upon lowering the pH and in the presence of magnesium ions, highlighting differences in RNA and DNA structures. A U6 RNA 1 × 2 loop sequence is rare in the databases examined.