Associations of flow disruptions with patient, staff, and process outcomes: a prospective observational study of robotic-assisted radical prostatectomies.

BACKGROUND: Technological advancements in the operating room (OR) have sparked new challenges for surgical workflow, OR professionals, and patient safety. Disruptive events are frequent across all surgical specialties, but little is known about their effects on patient outcomes and the influence of systemic factors. The aim was to explore the associations of intraoperative flow disruptions (FDs) with patient outcomes, staff workload, and surgery duration. METHODS: Prospective, single-center, and multi-source study comprising direct and standardized OR observations of urologic surgical procedures, clinical patient outcomes, and staff- and patient-reported outcome data (PROMs; 3-month follow-up). All data were recorded between 01/2020 and 10/2021. FDs were assessed using standardized procedure observations. Linear and logistic regression analyses including multiple system factors were used to explore the effects of FDs on surgical outcomes. RESULTS: 61 robotic-assisted radical prostatectomy procedures were captured (with 61 patients and 243 staff reports). High rates of FDs were observed; however, our analyses did not show significant relationships with patient complication rates. Equipment- and patient-related FDs were associated with increased staff workload. No association was found between higher rates of FDs and procedure duration. CONCLUSIONS: FDs were not related to inferior patient outcomes. Our findings may inform future OR investigations that scrutinize the complex interplay of human, team, process, and technological components that mitigate the effects of FDs during surgery.

Computer-assisted simulated workplace-based assessment in surgery: application of the universal framework of intraoperative performance within a mixed-reality simulation.

Objectives: Workplace-based assessment (WBA) is a key requirement of competency-based medical education in postgraduate surgical education. Although simulated workplace-based assessment (SWBA) has been proposed to complement WBA, it is insufficiently adopted in surgical education. In particular, approaches to criterion-referenced and automated assessment of intraoperative surgical competency in contextualized SWBA settings are missing.Main objectives were (1) application of the universal framework of intraoperative performance and exemplary adaptation to spine surgery (vertebroplasty); (2) development of computer-assisted assessment based on criterion-referenced metrics; and (3) implementation in contextualized, team-based operating room (OR) simulation, and evaluation of validity. Design: Multistage development and assessment study: (1) expert-based definition of performance indicators based on framework's performance domains; (2) development of respective assessment metrics based on preoperative planning and intraoperative performance data; (3) implementation in mixed-reality OR simulation and assessment of surgeons operating in a confederate team. Statistical analyses included internal consistency and interdomain associations, correlations with experience, and technical and non-technical performances. Setting: Surgical simulation center. Full surgical team set-up within mixed-reality OR simulation. Participants: Eleven surgeons were recruited from two teaching hospitals. Eligibility criteria included surgical specialists in orthopedic, trauma, or neurosurgery with prior VP or kyphoplasty experience. Main outcome measures: Computer-assisted assessment of surgeons' intraoperative performance. Results: Performance scores were associated with surgeons' experience, observational assessment (Objective Structured Assessment of Technical Skill) scores and overall pass/fail ratings. Results provide strong evidence for validity of our computer-assisted SWBA approach. Diverse indicators of surgeons' technical and non-technical performances could be quantified and captured. Conclusions: This study is the first to investigate computer-assisted assessment based on a competency framework in authentic, contextualized team-based OR simulation. Our approach discriminates surgical competency across the domains of intraoperative performance. It advances previous automated assessment based on the use of current surgical simulators in decontextualized settings. Our findings inform future use of computer-assisted multidomain competency assessments of surgeons using SWBA approaches.

Operating room team strategies to reduce flow disruptions in high-risk task episodes: resilience in robot-assisted surgery.

In healthcare work settings, flow disruptions (FDs) pose a potential threat to patient safety. Resilience research suggests that adaptive behavioural strategies contribute to preventing cognitive overload through FDs at crucial moments. We aimed to explore the nature and efficacy of operating room (OR) team strategies to prevent FDs in robot-assisted surgery. Within a mixed-methods design, we first asked surgical professionals, which strategies they apply, and secondly, identified behavioural strategies through direct observations. Findings were analysed using content analysis. Additionally, FDs were assessed through live observations in the OR. The sample included four interviewed experts and 15 observed surgical cases. Sixty originally received strategies were synthesised into 17 final OR team strategies. Overall, 658 FDs were observed with external FDs being the most frequent. During high-risk episodes, FDs were significantly reduced (p < 0.0001). The identified strategies reveal how OR teams deliberatively and dynamically manage and mitigate FDs during critical tasks. Our findings contribute to a nuanced understanding of adaptive strategies to safeguard performance in robot surgery services. Practitioner Summary: Flow disruptions (FDs) in surgical work may become a severe safety threat during high-risk situations. With interviews and observations, we explored team strategies applied to prevent FDs in critical moments. We obtained a comprehensive list of behavioural strategies and found that FDs were significantly reduced during a specific high-risk surgical task. Our findings emphasise the role of providers' and teams' adaptive capabilities to manage workflow in high-technology care environments.

RAS-NOTECHS: validity and reliability of a tool for measuring non-technical skills in robotic-assisted surgery settings.

BACKGROUND: Non-technical skills (NTS) are essential for safe surgical practice as they impact workflow and patient outcomes. Observational tools to measure operating room (OR) teams' NTS have been introduced. However, there are none that account for the specific teamwork challenges introduced by robotic-assisted surgery (RAS). We set out to develop and content-validate a tool to assess multidisciplinary NTS in RAS. METHODOLOGY: Stepwise, multi-method procedure. Observations in different surgical departments and a scoping literature review were first used to compile a set of RAS-specific teamwork behaviours. This list was refined and expert validated using a Delphi consensus approach consisting of qualitative interviews and a quantitative survey. Then, RAS-specific behaviours were merged with a well-established assessment tool on OR teamwork (NOTECHS II). Finally, the new tool-RAS-NOTECHS-was applied in standardized observations of real-world procedures to test its reliability (inter-rater agreement via intra-class correlations). RESULTS: Our scoping review revealed 5242 articles, of which 21 were included based on pre-established inclusion criteria. We elicited 16 RAS-specific behaviours from the literature base. These were synthesized with further 18 behavioural markers (obtained from 12 OR-observations) into a list of 26 behavioural markers. This list was reviewed by seven RAS experts and condensed to 15 expert-validated RAS-specific behavioural markers which were then merged into NOTECHS II. For five observations of urologic RAS procedures (duration: 13 h and 41 min), inter-rater agreement for identification of behavioural markers was strong. Agreement of RAS-NOTECHS scores indicated moderate to strong agreement. CONCLUSIONS: RAS-NOTECHS is the first observational tool for multidisciplinary NTS in RAS. In preliminary application, it has been shown to be reliable. Since RAS is rapidly increasing and challenges for effective and safe teamwork remain at the forefront of quality and safety of surgical care, RAS-NOTECHS may contribute to training and improvement efforts in technology-facilitated surgeries.

Intraoperative dynamics of workflow disruptions and surgeons' technical performance failures: insights from a simulated operating room.

INTRODUCTION: Flow disruptions (FD) in the operating room (OR) have been found to adversely affect the levels of stress and cognitive workload of the surgical team. It has been concluded that frequent disruptions also lead to impaired technical performance and subsequently pose a risk to patient safety. However, respective studies are scarce. We therefore aimed to determine if surgical performance failures increase after disruptive events during a complete surgical intervention. METHODS: We set up a mixed-reality-based OR simulation study within a full-team scenario. Eleven orthopaedic surgeons performed a vertebroplasty procedure from incision to closure. Simulations were audio- and videotaped and key surgical instrument movements were automatically tracked to determine performance failures, i.e. injury of critical tissue. Flow disruptions were identified through retrospective video observation and evaluated according to duration, severity, source, and initiation. We applied a multilevel binary logistic regression model to determine the relationship between FDs and technical performance failures. For this purpose, we compared FDs in one-minute intervals before performance failures with intervals without subsequent performance failures. RESULTS: Average simulation duration was 30:02 min (SD = 10:48 min). In 11 simulated cases, 114 flow disruption events were observed with a mean hourly rate of 20.4 (SD = 5.6) and substantial variation across FD sources. Overall, 53 performance failures were recorded. We observed no relationship between FDs and likelihood of immediate performance failures: Adjusted odds ratio = 1.03 (95% CI 0.46-2.30). Likewise, no evidence could be found for different source types of FDs. CONCLUSION: Our study advances previous methodological approaches through the utilisation of a mixed-reality simulation environment, automated surgical performance assessments, and expert-rated observations of FD events. Our data do not support the common assumption that FDs adversely affect technical performance. Yet, future studies should focus on the determining factors, mechanisms, and dynamics underlying our findings.

Associations of workflow disruptions in the operating room with surgical outcomes: a systematic review and narrative synthesis.

BACKGROUND: Performance in the operating room is an important determinant of surgical safety. Flow disruptions (FDs) represent system-related performance problems that affect the efficiency of the surgical team and have been associated with a risk to patient safety. Despite the growing evidence base on FDs, a systematic synthesis has not yet been published. OBJECTIVE: Our aim was to identify, evaluate and summarise the evidence on relationships between intraoperative FD events and provider, surgical process and patient outcomes. METHODS: We systematically searched databases MEDLINE, Embase and PsycINFO (last update: September 2019). Two reviewers independently screened the resulting studies at the title/abstract and full text stage in duplicate, and all inconsistencies were resolved through discussion. We assessed the risk of bias of included studies using established and validated tools. We summarised effects from included studies through a narrative synthesis, stratified based on predefined surgical outcome categories, including surgical process, provider and patient outcomes. RESULTS: We screened a total of 20 481 studies. 38 studies were found to be eligible. Included studies were highly heterogeneous in terms of methodology, medical specialty and context. Across studies, 20.5% of operating time was attributed to FDs. Various other process, patient and provider outcomes were reported. Most studies reported negative or non-significant associations of FDs with surgical outcomes. CONCLUSION: Apart from the identified relationship of FDs with procedure duration, the evidence base concerning the impact of FDs on provider, surgical process and patient outcomes is limited and heterogeneous. We further provide recommendations concerning use of methods, relevant outcomes and avenues for future research on associated effects of FDs in surgery.

Probing Nanoparticle/Membrane Interactions by Combining Amphiphilic Diblock Copolymer Assembly and Plasmonics.

Understanding the interactions between nanoparticles (NPs) and boundaries of cells is crucial both for their toxicity and therapeutic applications. Besides specific receptor-mediated endocytosis of surface-functionalized NPs, passive internalization is prompted by relatively unspecific parameters, such as particle size and charge. Based on theoretical treatments, adhesion to and bending of the cell membrane can induce NP wrapping. Experimentally, powerful tools are needed to selectively probe possible membrane-NP motifs at very dilute conditions and avoid dye labeling. In this work, we employ surface resonance-enhanced dynamic light scattering, surface plasmon resonance, electron microscopy, and simulations for sensing interactions between plasmonic AuNPs and polymersomes. We distinguish three different interaction scenarios at nanomolar concentrations by tuning the surface charge of AuNPs and rationalize these events by balancing vesicle bending and electrostatic/van der Waals AuNP and vesicle adhesion. The clarification of the physical conditions under which nanoparticles passively translocate across membranes can aid in the rational design of drugs that cannot exploit specific modes of cellular uptake and also elucidates physical properties that render nanoparticles in the environment particularly toxic.

An Animal Model Further Uncovers the Role of Mutant BrafV600E during Papillary Thyroid Cancer Development.

Papillary thyroid carcinomas (PTCs) account for 90% of human thyroid cancer cases, which represent 1% of all cancer cases. They are likely to develop from papillary thyroid microcarcinomas (PTMCs), found in up to 36% of healthy individuals, due to rare progression events (0.01%). Although the prognosis of PTCs is excellent, 5% to 10% of tumors display an unfavorable outcome. About 45% of PTCs exhibit activating BRAFV600E mutations. Rats of the inbred BD strains postnatally exposed to the carcinogen N-ethyl-N-nitrosourea developed PTMCs, which closely resembled their human counterparts judging from their histology, size, and marginal tendency to progress. DNA sequencing revealed mutations in exon 15 of the Braf gene identical to the human BRAFV600E mutation in 82% of the cases. Predominantly a 50:50 ratio of wild-type to mutant Braf alleles was seen regardless of tumor size or animal age, indicating that the Braf mutation is an early, if not the initial, event in rat PTMC development. Surprisingly, most PTMCs carrying a confirmed BrafV600E mutation did not display BrafV600E protein expression. As the BrafV600Egene is supposed to be the driver in PTC development, down-regulation of expression should contribute to the low risk for progression of PTMC. This model system will enable further insights into the molecular mechanisms of PTMC initiation and progression to PTC, further translating into targeted tumor prevention strategies/therapies.

Say, What Is on Your Mind? Surgeons' Evaluations of Realism and Usability of a Virtual Reality Vertebroplasty Simulator.

BACKGROUND: Virtual reality (VR)-based simulations offer rich opportunities for surgical skill training and assessment of surgical novices and experts. A structured evaluation and validation process of such training and assessment tools is necessary for effective surgical learning environments. OBJECTIVE: To develop and apply a classification system of surgeon-reported experience during operation of a VR vertebroplasty simulator. METHODS: A group of orthopedic, trauma surgeons and neurosurgeons (n = 13) with various levels of expertise performed on a VR vertebroplasty simulator. We established a mixed-methods design using think-aloud protocols, senior surgical expert evaluations, performance metrics, and a post-simulation questionnaire. Verbal content was systematically analyzed using structured qualitative content analysis. We established a category system for classification of surgeons' verbal evaluations during the simulation. Furthermore, we evaluated intraoperative performance metrics and explored potential associations with surgeons' characteristics and simulator evaluation. RESULTS: Overall, 244 comments on realism and usability of the vertebroplasty simulator were collected. This included positive and negative remarks, questions, and specific suggestions for improvement. Further findings included surgeons' approval of the realism and usability of the simulator and the observation that the haptic feedback of the VR patient's anatomy requires further improvement. Surgeon-reported evaluations were not associated with performance decrements. DISCUSSION: This study is the first to apply think-aloud protocols for evaluation of a surgical VR-based simulator. A novel classification approach is introduced that can be used to classify surgeons' verbalized experiences during simulator use. Our lessons learned may be valuable for future research with similar methodological approach.

Light Scattering Analysis of Mono- and Multi-PEGylated Bovine Serum Albumin in Solution: Role of Composition on Structure and Interactions.

The effect of polymer conjugation on the interactions between proteins in solution is evaluated by systematic analysis of the second virial coefficient (A2) for the particular example of single- and double-PEGylated bovine serum albumin (PEG-BSA) in dilute PBS solution. The effect of PEGylation on A2 is found to sensitively depend on both the composition and the distribution of PEG segments within the conjugate. Most importantly, at a given PEG volume fraction, A2 significantly increases with the degree of polymerization of tethered chains. Hence, a lesser number of long chains is more effective in solubilizing BSA than a correspondingly larger number of short chains. Analysis of the hydrodynamic radii of protein-PEG conjugates suggests that the increased solubility is concurrent with a structural transition in the case of high molecular PEG grafts that results in compact core-shell-type structures. The results reveal a link between the composition, structure, and solubility of polymer conjugates that might benefit the understanding of their biochemical characteristics and their design for functional material applications.

Synthesis and conformation of 3,6-connected cyclohexadiene chains.

3,6-Connected cyclohexadienes as precursors for polyphenylenes are synthesized and characterized by mass spectrometry and NMR spectroscopy. Pure fractions of trimers, hexamers, and nonamers are collected after separation of the product mixture by recycling GPC. The anticipated formation of rigid linear structures, due to the trans-configuration of the monomeric units, is supported by density functional theory and experimentally confirmed by dynamic light scattering from dilute solution at low scattering angles. The obtained translational diffusion coefficients are represented by rigid rod-like or prolate ellipsoid-like molecular shapes. The measurements of diffusion coefficients reveal a length-dependent ratio of 1:2:3 between the three oligomers, which directly correlates to the expected length extension from trimer to nonamer.

Surface asymmetry of coated spherical nanoparticles.

We validate the nonspherical grafting arrangement of isotropically coated spherical nanoparticles as very recently proposed. We utilize localized surface plasmon resonance enhanced dynamic polarized and depolarized light scattering from Au nanoparticles, the spherical symmetry of which was revealed by single-particle dark-field spectroscopy. The same Au nanospheres are grafted with ligands of different chemistry and length. The wavelength dependent depolarization ratio and the two transport coefficients of these nanoparticles, obtained from the dynamic light scattering experiment, can only be reconciled with the TEM data, the single UV/vis extinction spectrum, and the dark-field spectroscopy experiments if their coating is described as asymmetric. Spatially anisotropic graft distribution on spherical nanoparticles impacts their assembly and understanding its origin will help control the structure and properties of polymer nanocomposites.

Synthesis of structurally well-defined and liquid-phase-processable graphene nanoribbons.

The properties of graphene nanoribbons (GNRs) make them good candidates for next-generation electronic materials. Whereas 'top-down' methods, such as the lithographical patterning of graphene and the unzipping of carbon nanotubes, give mixtures of different GNRs, structurally well-defined GNRs can be made using a 'bottom-up' organic synthesis approach through solution-mediated or surface-assisted cyclodehydrogenation reactions. Specifically, non-planar polyphenylene precursors were first 'built up' from small molecules, and then 'graphitized' and 'planarized' to yield GNRs. However, fabrication of processable and longitudinally well-extended GNRs has remained a major challenge. Here we report a bottom-up solution synthesis of long (>200 nm) liquid-phase-processable GNRs with a well-defined structure and a large optical bandgap of 1.88 eV. Self-assembled monolayers of GNRs can be observed by scanning probe microscopy, and non-contact time-resolved terahertz conductivity measurements reveal excellent charge-carrier mobility within individual GNRs. Such structurally well-defined GNRs may prove useful for fundamental studies of graphene nanostructures, as well as the development of GNR-based nanoelectronics.

End-functionalized ROMP polymers for Biomedical Applications.

We present two novel allyl-based terminating agents that can be used to end-functionalize living polymer chains obtained by ring-opening metathesis polymerization (ROMP) using Grubbs' third generation catalyst. Both terminating agents can be easily synthesized and yield ROMP polymers with stable, storable activated ester groups at the chain-end. These end-functionalized ROMP polymers are attractive building blocks for advanced polymeric materials, especially in the biomedical field. Dye-labeling and surface-coupling of antimicrobially active polymers using these end-groups were demonstrated.

Structural brain changes in tinnitus: grey matter decrease in auditory and non-auditory brain areas.

Tinnitus, the phantom perception of sound, is a frequent disorder that causes significant morbidity. The pathophysiological mechanisms involved in tinnitus generation are still under exploration. Electrophysiological and functional neuroimaging studies give increasing evidence for abnormal functioning both within the central auditory system and in non-auditory brain areas. However, observed changes show great variability, hence lacking a conclusive picture. Recently, structural alterations in the central nervous system have been detected in tinnitus patients by voxel-based morphometry (VBM). Here we aimed to replicate these findings in an independent study sample. We performed structural MRI scans in 28 tinnitus patients with normal audiometry and used VBM to compare results with a control group, matched for age, sex and hearing status. As major results we found significant grey matter decreases in the tinnitus group in the right inferior colliculus and in the left hippocampus. However, neither changes in the subcallosal area nor in the thalamus as described recently have been observed. Our results underscore that (1.) VBM allows to detect structural alterations in tinnitus patients, which seem to be related to tinnitus pathophysiology. (2.) Both, areas in the auditory and the limbic system are involved giving further evidence for the important role of the limbic system in the pathophysiology of tinnitus. (3.) Even groups with similar clinical characteristics might differ in the underlying neurobiological changes.