Intravascular Ultrasound May Not Impact Graft Sizing in Endovascular Repair of Blunt Thoracic Aortic Injury.

OBJECTIVES: Thoracic endovascular aortic repair (TEVAR) is the preferred treatment for severe blunt thoracic aortic injuries (BTAI). Successful outcomes rely on accurate endograft sizing, but initial imaging may underestimate aortic diameters. This study examines the impact of intravascular ultrasound (IVUS) on endograft sizing and clinical outcomes in BTAI patients. METHODS: A prospectively collected multi-institutional dataset from the Aortic Trauma Foundation was analyzed. Patients with BTAI undergoing TEVAR with IVUS were compared to patients who underwent TEVAR alone. Demographics and operative variables were compared, focusing on IVUS effects on endograft sizing by examining maximal proximal and distal aortic diameter on initial CT imaging compared to the graft diameters used during TEVAR. RESULTS: 293 patients underwent TEVAR for BTAI with IVUS utilized in 124 cases (42.3%). The average graft size in the IVUS and non-IVUS groups were similar proximally (26.91 ± 4.3 mm IVUS vs 27.77 ± 4.7 mm non-IVUS, P = 0.116) and distally (25.96 ± 4.7 mm IVUS vs 26.51 ± 4.7 mm non-IVUS). IVUS did not impact the difference between graft size and initial CT measurements proximally (4.32 ± 4.8 mm IVUS vs 4.23 ± 3.9 mm non-IVUS, P = 0.859) or distally (4.17 ± 5.9 mm IVUS vs 4.50 ± 4.3 mm non-IVUS, P = 0.606). Although delayed hemorrhagic and ischemic stroke occurred less frequently in IVUS patients (0.8% IVUS vs 7.1% non- IVUS, P = 0.024), in-hospital mortality was similar between groups (5.6% IVUS vs 7.7% non-IVUS, P = 0.581). CONCLUSIONS: IVUS is not associated with significant changes in endograft sizing compared to sizing based on CT scan alone in BTAI patients. IVUS was not associated with differences in mortality but was associated with a decrease in delayed hemorrhagic and ischemic stroke. Routine IVUS in BTAI patients may not be necessary for accurate sizing, but there may be a relationship between IVUS and stroke.

Fourth-Year Medical Students' Perceptions of Vascular Surgery: Can We Improve the Pipeline?

BACKGROUND: Since their inception, Integrated Vascular Surgery Residency (IVSR) programs have expanded widely and attracted highly competitive medical students by offering a more focused approach to learning both open surgical and endovascular techniques. However, despite substantial modifications to the training paradigm, a shortage of vascular surgeons is still projected through 2050. We aimed to gather and analyze fourth-year medical students' knowledge and perceptions of vascular surgery (VS) to further inform strategies for recruiting future vascular surgeons. METHODS: We sent anonymous electronic questionnaires to fourth-year medical students at 7 allopathic and 3 osteopathic medical schools, with questions detailing demographics, specialty preferences, and exposure to and perceptions of VS. Descriptive statistics were obtained, and responses were compared between students applying to surgical specialties (SS) and nonsurgical specialties (NSS). RESULTS: Two hundred eleven of 1,764 (12%) participants responded (56% female). 56% reported VS exposure, most commonly during the third year. 64 (30%) planned to apply to SS. 57% of respondents reported knowledge of the management of vascular disease, and 56% understood procedures performed by vascular surgeons. Ranking the importance of factors in choosing specialties, SS selected "experiences gained during medical school rotations" (P < 0.05), "types and/or variety of treatment modalities used in this field" (P < 0.001), and "interest in the pathology or disease processes treated" (P < 0.05) as highest priorities. NSS preferred "lifestyle (work-life balance) as an attending" (P < 0.001). Only 7% of all respondents believed vascular surgeons have a good work-life balance, with a larger percentage of SS (P < 0.001) agreeing. Stratified by gender, female students rated "limited ability of childbirth during residency and/or postponement of family plans" (P < 0.05), "gender-related concerns, such as discrimination at work or unfair career possibilities" (P < 0.001), and "fear of unfair competition" (P < 0.05) as potential negative aspects of VS careers. 55% of respondents believed the IVSR makes VS more appealing. CONCLUSIONS: Medical students perceive poor quality of life and work-life balance as deterring factors to a career in VS. Opportunities exist to educate students on the pathologies treated, procedures performed, and attainable quality of life available in our field. We should also continue to develop recruitment strategies to stimulate student interest and increase early exposure in VS.

F Plasmids Are the Major Carriers of Antibiotic Resistance Genes in Human-Associated Commensal Escherichia coli.

The evolution and propagation of antibiotic resistance by bacterial pathogens are significant threats to global public health. Contemporary DNA sequencing tools were applied here to gain insight into carriage of antibiotic resistance genes in Escherichia coli, a ubiquitous commensal bacterium in the gut microbiome in humans and many animals, and a common pathogen. Draft genome sequences generated for a collection of 101 E. coli strains isolated from healthy undergraduate students showed that horizontally acquired antibiotic resistance genes accounted for most resistance phenotypes, the primary exception being resistance to quinolones due to chromosomal mutations. A subset of 29 diverse isolates carrying acquired resistance genes and 21 control isolates lacking such genes were further subjected to long-read DNA sequencing to enable complete or nearly complete genome assembly. Acquired resistance genes primarily resided on F plasmids (101/153 [67%]), with smaller numbers on chromosomes (30/153 [20%]), IncI complex plasmids (15/153 [10%]), and small mobilizable plasmids (5/153 [3%]). Nearly all resistance genes were found in the context of known transposable elements. Very few structurally conserved plasmids with antibiotic resistance genes were identified, with the exception of an ∼90-kb F plasmid in sequence type 1193 (ST1193) isolates that appears to serve as a platform for resistance genes and may have virulence-related functions as well. Carriage of antibiotic resistance genes on transposable elements and mobile plasmids in commensal E. coli renders the resistome highly dynamic.IMPORTANCE Rising antibiotic resistance in human-associated bacterial pathogens is a serious threat to our ability to treat many infectious diseases. It is critical to understand how acquired resistance genes move in and through bacteria associated with humans, particularly for species such as Escherichia coli that are very common in the human gut but can also be dangerous pathogens. This work combined two distinct DNA sequencing approaches to allow us to explore the genomes of E. coli from college students to show that the antibiotic resistance genes these bacteria have acquired are usually carried on a specific type of plasmid that is naturally transferrable to other E. coli, and likely to other related bacteria.