Development and usability testing of a fully immersive VR simulation for REBOA training.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a potentially life-saving procedure for bleeding trauma patients. Being a rare and complex procedure performed in extreme situations, repetitive training of REBOA teams is critical. Evidence-based guidelines on how to train REBOA are missing, although simulation-based training has been shown to be effective but can be costly and complex. We aimed to determine the feasibility and acceptance of REBOA training using a fully immersive virtual reality (VR) REBOA simulation, as well as assess the confidence in conducting the REBOA procedure before and after the training. METHODS: Prospective feasibility pilot study of prehospital emergency physicians and paramedics in Bern, Switzerland, from November 2020 until March 2021. Baseline characteristics of trainees, prior training and experience in REBOA and with VR, variables of media use (usability: system usability scale, immersion/presence: Slater-Usoh-Steed, workload: NASA-TLX, user satisfaction: USEQ) as well as confidence prior and after VR training were accessed. RESULTS: REBOA training in VR was found to be feasible without relevant VR-specific side-effects. Usability (SUS median 77.5, IQR 71.3-85) and sense of presence and immersion (Slater-Usoh-Steed median 4.8, IQR 3.8-5.5) were good, the workload without under-nor overstraining (NASA-TLX median 39, IQR 32.8-50.2) and user satisfaction high (USEQ median 26, IQR 23-29). Confidence of trainees in conducting REBOA increased significantly after training (p < 0.001). CONCLUSIONS: Procedural training of the REBOA procedure in immersive virtual reality is possible with a good acceptance and high usability. REBOA VR training can be an important part of a training curriculum, with the virtual reality-specific advantages of a time- and instructor-independent learning.

The burden on public emergency departments during the economic crisis years in Greece: a two-center comparative study.

OBJECTIVES: The effects of the Greek economic crisis on the emergency departments (EDs) of public hospitals have not been evaluated. The study aims to evaluate the burden of the financial crisis on public hospital's EDs. STUDY DESIGN: The present study is a retrospective two-center comparative study. METHODS: ED visits, related admissions per year, and the admissions/visits ratio at two public Greek hospitals, the Sismanogleio of Athens (SHA) and the University Hospital of Crete (UHC), from 2008 to 2016 were retrospectively studied. A linear model was fitted for each variable, and the slope values of the linear equations were calculated and compared between the two institutions. RESULTS: ED visits of the UHC exhibited 8.9% increase during the study period, whereas related admissions and admissions/visits ratio increased by 23.4% and 12.5%, respectively. ED visits at the SHA exhibited 5.4% increase, whereas related admissions showed 6% decrease and the admissions/visits ratio was decreased by 8%. Significant differences between the rates of admissions (P < 0.001) and admissions/visits ratio (P = 0.001) among the two hospitals were observed. CONCLUSIONS: Both institutions showed similarly increased ED visits. However, the UHC serving mainly rural, but also suburban and urban population, exhibited different changes regarding admissions and admissions/visits ratio compared with the SHA serving mainly an urban and suburban one, reflecting the way the crisis affected each social group. Depression has amplified the Greek National Health System structural problems and exposed the problematic urban primary health care. Improvement of primary urban health care, autonomy of EDs, and establishment of emergency medicine as independent specialty in Greece could serve better patients seeking care in public hospitals' EDs.

Surgical management of lung cancer invading the aorta or the superior vena cava.

OBJECTIVE: Invasion of mediastinal structures (T4) is considered as an absolute contraindication to surgical management of non-small cell lung cancer (NSCLC). The authors studied the role of surgical treatment in case of direct aortic and superior venous caval involvement. PATIENTS: From 1995 to 2000, 13 patients with left lung NSCLC invading descending aorta and 9 patients with right upper lobe NSCLC and superior vena cava (SVC) invasion were subjected to thoracotomy for lung resection. Surgery was indicated in case of absence of intraluminal extension. All patients were cN2 negative. The pathology results and 5-year survival were recorded and analyzed. RESULTS: In three cases (23%) the tumor was adhered to the parietal pleura overlying descending aorta, which was resected en block with tumor-associated lung parenchyma. Aortic adventitia invasion by tumor led to local resection of adventitia (<1cm(2)) in nine patients (69%). Invasion deeper than adventitia was encountered in one case (8%), which was managed with aortic partial occlusion, resection of aortic wall and repair of the defect with Gore graft patch. In three patients (33%) the SVC wall was involved by the tumor 1-3cm in length and 2-4mm of the circumference. The defect was repaired with direct suturing. In five patients (56%) the area of SVC wall that was invaded was 3cmx2cm. The defect was repaired with Dacron patch. In 1 patient (11%) an arterial 14 graft was end-to-end interposed. All resections were radical (R0). Neither associated postoperative complications nor operative mortality was recorded. Five-year survival was 30.7% for the cases with aortic invasion and 11% for the ones with SVC involvement. CONCLUSIONS: Radical surgical resection of lung tumors with localized aortic invasion can be considered after exclusion of N2 involvement.

From first base: the sequence of the tip of the X chromosome of Drosophila melanogaster, a comparison of two sequencing strategies.

We present the sequence of a contiguous 2.63 Mb of DNA extending from the tip of the X chromosome of Drosophila melanogaster. Within this sequence, we predict 277 protein coding genes, of which 94 had been sequenced already in the course of studying the biology of their gene products, and examples of 12 different transposable elements. We show that an interval between bands 3A2 and 3C2, believed in the 1970s to show a correlation between the number of bands on the polytene chromosomes and the 20 genes identified by conventional genetics, is predicted to contain 45 genes from its DNA sequence. We have determined the insertion sites of P-elements from 111 mutant lines, about half of which are in a position likely to affect the expression of novel predicted genes, thus representing a resource for subsequent functional genomic analysis. We compare the European Drosophila Genome Project sequence with the corresponding part of the independently assembled and annotated Joint Sequence determined through "shotgun" sequencing. Discounting differences in the distribution of known transposable elements between the strains sequenced in the two projects, we detected three major sequence differences, two of which are probably explained by errors in assembly; the origin of the third major difference is unclear. In addition there are eight sequence gaps within the Joint Sequence. At least six of these eight gaps are likely to be sites of transposable elements; the other two are complex. Of the 275 genes in common to both projects, 60% are identical within 1% of their predicted amino-acid sequence and 31% show minor differences such as in choice of translation initiation or termination codons; the remaining 9% show major differences in interpretation.

From sequence to chromosome: the tip of the X chromosome of D. melanogaster.

One of the rewards of having a Drosophila melanogaster whole-genome sequence will be the potential to understand the molecular bases for structural features of chromosomes that have been a long-standing puzzle. Analysis of 2.6 megabases of sequence from the tip of the X chromosome of Drosophila identifies 273 genes. Cloned DNAs from the characteristic bulbous structure at the tip of the X chromosome in the region of the broad complex display an unusual pattern of in situ hybridization. Sequence analysis revealed that this region comprises 154 kilobases of DNA flanked by 1.2-kilobases of inverted repeats, each composed of a 350-base pair satellite related element. Thus, some aspects of chromosome structure appear to be revealed directly within the DNA sequence itself.

One-hundred and five new potential Drosophila melanogaster genes revealed through STS analysis.

Complementation analysis had suggested that the Drosophila melanogaster genome contains approximately 5000 genes, but it is now generally accepted that the actual number is several times as high. We report here an analysis of 1788 anonymous sequence tagged sites (STSs) from the European Drosophila Genome Project (EDGP), totalling 463 kb. The data reveal a substantial number of previously undescribed potential genes, amounting to 6.1% of the number of Drosophila genes already in the sequence databases.

A physical map of the X chromosome of Drosophila melanogaster: cosmid contigs and sequence tagged sites.

A physical map of the euchromatic X chromosome of Drosophila melanogaster has been constructed by assembling contiguous arrays of cosmids that were selected by screening a library with DNA isolated from microamplified chromosomal divisions. This map, consisting of 893 cosmids, covers approximately 64% of the euchromatic part of the chromosome. In addition, 568 sequence tagged sites (STS), in aggregate representing 120 kb of sequenced DNA, were derived from selected cosmids. Most of these STSs, spaced at an average distance of approximately 35 kb along the euchromatic region of the chromosome, represent DNA tags that can be used as entry points to the fruitfly genome. Furthermore, 42 genes have been placed on the physical map, either through the hybridization of specific probes to the cosmids or through the fact that they were represented among the STSs. These provide a link between the physical and the genetic maps of D. melanogaster. Nine novel genes have been tentatively identified in Drosophila on the basis of matches between STS sequences and sequences from other species.