Operating theatre related syncope in medical students: a cross sectional study

<p>Abstract</p> <p>Background</p> <p>Observing surgical procedures is a beneficial educational experience for medical students during their surgical placements. Anecdotal evidence suggests that operating theatre related syncope may have detrimental effects on students' views of this. Our study examines the frequency and causes of such syncope, together with effects on career intentions, and practical steps to avoid its occurrence.</p> <p>Methods</p> <p>All penultimate and final year students at a large UK medical school were surveyed using the University IT system supplemented by personal approach. A 20-item anonymous questionnaire was distributed and results were analysed using the Statistical Package for Social Sciences, version 15.0 (Chicago, Illinois, USA).</p> <p>Results</p> <p>Of the 630 clinical students surveyed, 77 responded with details of at least one near or actual operating theatre syncope (12%). A statistically significant gender difference existed for syncopal/near-syncopal episodes (male 12%; female 88%), p < 0.05. Twenty-two percent of those affected were graduate entry medical course students with the remaining 78% undergraduate. Mean age was 23-years (range 20 – 45). Of the 77 reactors, 44 (57%) reported an intention to pursue a surgical career. Of this group, 7 (9%) reported being discouraged by syncopal episodes in the operating theatre. The most prevalent contributory factors were reported as hot temperature (n = 61, 79%), prolonged standing (n = 56, 73%), wearing a surgical mask (n = 36, 47%) and the smell of diathermy (n = 18, 23%). The most frequently reported measures that students found helpful in reducing the occurrence of syncopal episodes were eating and drinking prior to attending theatre (n = 47, 61%), and moving their legs whilst standing (n = 14, 18%).</p> <p>Conclusion</p> <p>Our study shows that operating theatre related syncope among medical students is common, and we establish useful risk factors and practical steps that have been used to prevent its occurrence. Our study also highlights the detrimental effect of this on the career intentions of medical students interested in surgery. Based on these findings, we recommend that dedicated time should be set aside in surgical teaching to address this issue prior to students attending the operating theatre.</p

Tauroursodeoxycholic Acid Improves Motor Symptoms in a Mouse Model of Parkinson's Disease

Parkinson's disease (PD) is characterized by severe motor symptoms, and currently there is no treatment that retards disease progression or reverses damage prior to the time of clinical diagnosis. Tauroursodeoxycholic acid (TUDCA) is neuroprotective in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD; however, its effect in PD motor symptoms has never been addressed. In the present work, an extensive behavior analysis was performed to better characterize the MPTP model of PD and to evaluate the effects of TUDCA in the prevention/improvement of mice phenotype. MPTP induced significant alterations in general motor performance paradigms, including increased latency in the motor swimming, adhesive removal and pole tests, as well as altered gait, foot dragging, and tremors. TUDCA administration, either before or after MPTP, significantly reduced the swimming latency, improved gait quality, and decreased foot dragging. Importantly, TUDCA was also effective in the prevention of typical parkinsonian symptoms such as spontaneous activity, ability to initiate movement and tremors. Accordingly, TUDCA prevented MPTP-induced decrease of dopaminergic fibers and ATP levels, mitochondrial dysfunction and neuroinflammation. Overall, MPTP-injected mice presented motor symptoms that are aggravated throughout time, resembling human parkinsonism, whereas PD motor symptoms were absent or mild in TUDCA-treated animals, and no aggravation was observed in any parameter. The thorough demonstration of improvement of PD symptoms together with the demonstration of the pathways triggered by TUDCA supports a subsequent clinical trial in humans and future validation of the application of this bile acid in PD.National funds, through the Foundation for Science and Technology (Portugal) (FCT), under the scope of the projects PTDC/NEU-NMC/0248/2012, UID/DTP/04138/2013 and POCI-01-0145-FEDER-007038, and post-doctoral grants SFRH/BPD72891/2010 (to A.I.R.), SFRH/BPD/95855/2013 (to M.J.N.), SFRH/BPD/98023/2013 (to A.N.C.), SFRH/BPD/91562/2012 (to A.S.F.) and UMINHO/BI/248/2016 (to S.D.S.). This work has also been developed under the scope of the project NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Program (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER), and by FEDER funds, through the Competitiveness Factors Operational Program (COMPETE)info:eu-repo/semantics/publishedVersio

Post-Vasectomy Semen Analysis: Optimizing Laboratory Procedures and Test Interpretation through a Clinical Audit and Global Survey of Practices

Purpose: The success of vasectomy is determined by the outcome of a post-vasectomy semen analysis (PVSA). This article describes a step-by-step procedure to perform PVSA accurately, report data from patients who underwent post vasectomy semen analysis between 2015 and 2021 experience, along with results from an international online survey on clinical practice. Materials and methods: We present a detailed step-by-step protocol for performing and interpretating PVSA testing, along with recommendations for proficiency testing, competency assessment for performing PVSA, and clinical and laboratory scenarios. Moreover, we conducted an analysis of 1,114 PVSA performed at the Cleveland Clinic's Andrology Laboratory and an online survey to understand clinician responses to the PVSA results in various countries. Results: Results from our clinical experience showed that 92.1% of patients passed PVSA, with 7.9% being further tested. A total of 78 experts from 19 countries participated in the survey, and the majority reported to use time from vasectomy rather than the number of ejaculations as criterion to request PVSA. A high percentage of responders reported permitting unprotected intercourse only if PVSA samples show azoospermia while, in the presence of few non-motile sperm, the majority of responders suggested using alternative contraception, followed by another PVSA. In the presence of motile sperm, the majority of participants asked for further PVSA testing. Repeat vasectomy was mainly recommended if motile sperm were observed after multiple PVSA's. A large percentage reported to recommend a second PVSA due to the possibility of legal actions. Conclusions: Our results highlighted varying clinical practices around the globe, with controversy over the significance of non-motile sperm in the PVSA sample. Our data suggest that less stringent AUA guidelines would help improve test compliance. A large longitudinal multi-center study would clarify various doubts related to timing and interpretation of PVSA and would also help us to understand, and perhaps predict, recanalization and the potential for future failure of a vasectomy

Obesity-Related Oxidative Stress: the Impact of Physical Activity and Diet Manipulation

Obesity-related oxidative stress, the imbalance between pro-oxidants and antioxidants (e.g., nitric oxide), has been linked to metabolic and cardiovascular disease, including endothelial dysfunction and atherosclerosis. Reactive oxygen species (ROS) are essential for physiological functions including gene expression, cellular growth, infection defense, and modulating endothelial function. However, elevated ROS and/or diminished antioxidant capacity leading to oxidative stress can lead to dysfunction. Physical activity also results in an acute state of oxidative stress. However, it is likely that chronic physical activity provides a stimulus for favorable oxidative adaptations and enhanced physiological performance and physical health, although distinct responses between aerobic and anaerobic activities warrant further investigation. Studies support the benefits of dietary modification as well as exercise interventions in alleviating oxidative stress susceptibility. Since obese individuals tend to demonstrate elevated markers of oxidative stress, the implications for this population are significant. Therefore, in this review our aim is to discuss (i) the role of oxidative stress and inflammation as associated with obesity-related diseases, (ii) the potential concerns and benefits of exercise-mediated oxidative stress, and (iii) the advantageous role of dietary modification, including acute or chronic caloric restriction and vitamin D supplementation

Quantifying Sources of Variability in Infancy Research Using the Infant-Directed-Speech Preference

Psychological scientists have become increasingly concerned with issues related to methodology and replicability, and infancy researchers in particular face specific challenges related to replicability: For example, high-powered studies are difficult to conduct, testing conditions vary across labs, and different labs have access to different infant populations. Addressing these concerns, we report on a large-scale, multisite study aimed at (a) assessing the overall replicability of a single theoretically important phenomenon and (b) examining methodological, cultural, and developmental moderators. We focus on infants’ preference for infant-directed speech (IDS) over adult-directed speech (ADS). Stimuli of mothers speaking to their infants and to an adult in North American English were created using seminaturalistic laboratory-based audio recordings. Infants’ relative preference for IDS and ADS was assessed across 67 laboratories in North America, Europe, Australia, and Asia using the three common methods for measuring infants’ discrimination (head-turn preference, central fixation, and eye tracking). The overall meta-analytic effect size (Cohen’s d) was 0.35, 95% confidence interval = [0.29, 0.42], which was reliably above zero but smaller than the meta-analytic mean computed from previous literature (0.67). The IDS preference was significantly stronger in older children, in those children for whom the stimuli matched their native language and dialect, and in data from labs using the head-turn preference procedure. Together, these findings replicate the IDS preference but suggest that its magnitude is modulated by development, native-language experience, and testing procedure

Normal Variation of the Lisfranc Joint: Tridimensional Analysis using Weight-Bearing Computed Tomography Imaging

Category: Midfoot/Forefoot; Trauma Introduction/Purpose: Untreated Lisfranc injuries can lead to chronic pain, midfoot arthritis, and functional disability 1,2,5. Approximately 20% of Lisfranc injuries are misdiagnosed or completely missed on initial evaluation, which can be attributed to a lack of parameters of what is within normal limits for subjects without injury in the Lisfranc complex3,4. The purpose of this study is to identify anatomic variations of unidimensional, bidimensional, and tridimensional (1D, 2D, 3D) measurements of the Lisfranc complex of normal individuals using weight-bearing computed tomography (WBCT) imaging. Our hypothesis is that there is some variation among individuals with a difference between right and left of the same individual of less than 10%. Methods: A total of 191 subjects with bilateral WBCT scans of the foot were collected from three tertiary medical centers from 2019-2022. Exclusion criteria included: history of Lisfranc injury, first to fourth metatarsal base fractures, Charcot arthropathy, midfoot arthritis, cuneiform fractures, and forefoot surgery proximal to the metatarsal neck region. The following Lisfranc joint measurements were collected6 bilaterally: joint volume (3D), area of the joint on a consistent axial slice (2D), and distance between the second metatarsal and medial cuneiform (1D). Foot alignment was assessed using lateral talar-first metatarsal angle (Meary’s Angle). Patient demographics (age, sex, weight, height, BMI) were also collected. Descriptive statistics were calculated for quantitative variables. Percent difference was used to assess volume, area, and distance variation between sides.7 Correlation between demographic data and Lisfranc measurements was assessed using Pearson Correlation tests. A T-test was used for categorical variables. A p-value < 0.05 was considered statistically significant. Results: The cohort included 61% female and 39% male with an average age of 45.2±17.3 years. The mean volume, area, and distance measurements of the Lisfranc joint for both left and right sides are shown in Figure 1. Overall, the mean percent difference between left and right sides were 11.9%, 14.9% and 13.9% for volume, area and diastasis, respectively (Figure 1). No association was found between age, BMI, or weight and the volume, area or distance measurements. A correlation (r=0.48, p= < 0.001) was found between height and left Lisfranc joint volume, but no other measurements. Significant difference between sex in volume (p < 0.001) and area (p < 0.001) measurements were found. Foot alignment did not have a correlation with a variation of the Lisfranc complex measurements. Conclusion: This study provides an objective characterizing of the anatomic variations of the Lisfranc joint amongst healthy individuals. Differences in the measurements and the large standard deviation in absolute measurements of volume, area, and distance suggests that percent difference with the contralateral side may be a better metric to use to diagnose Lisfranc instability. Our results showed that the difference between bilateral sides in a patient is less than 15% for volume, area, and diastasis. The results of this study can set the foundation for future studies to determine the cut-off value for the diagnosis of Lisfranc instability using WBCT imaging

Chevron vs Oblique Medial Displacement Calcaneal Osteotomy - Which Is More Stable? Results From a Finite Element Analysis Study

Category: Hindfoot; Ankle Introduction/Purpose: The medial displacement calcaneal osteotomy is used to correct hindfoot valgus in adult-acquired flatfoot disease(AAFD). This is done by means of an oblique cut, which is then translated medially. The chevron variant of the MDCO has gained popularity in recent times. This osteotomy involves a V-cut, with the apex of the V placed anteriorly. This is thought to be inherently more stable than the conventional MDCO owing to its geometrical design and higher contact area, especially with higher magnitudes of translation of the osteotomized fragment. However, it is technically more demanding, and many surgeons may not be familiar with the technique. Moreover, there is no literature comparing the stability of the chevron and oblique MDCO. Hence, we conducted this study to address this knowledge gap. Methods: Computed Tomography (CT) scan of the foot of a patient diagnosed with Johnson stage 2 AAFD was segmented and converted into a 3D computational model. Subsequently, oblique and chevron (160o V-angle) calcaneal osteotomies were performed virtually. For each variant, the osteotomized fragment was translated medially by 8-, 10- and 12-mm and then fixed virtually with two 6.5 mm screws. The six models were imported into a Finite Element Software (ANSYS v19) and subjected to 500 N axial loading through the tibia to simulate a single-leg stance. The von Mises stresses at the osteotomy interfaces and the screws, and the total displacement of the posterior fragment was recorded for each model. Results: The compiled simulation results are presented in Table 1. For both osteotomies, the overall stresses at the osteotomy contact site and the screws increased incrementally with increasing medial translation. Similarly, sagittal plane displacement of the anterior fragment was noted to follow a similar trend. Across all translation levels, the stresses were recorded to be lower for chevron MDCO when compared to the oblique variants. Relative fragment displacement was also noted to be lower for the chevron MDCO. Conclusion: The chevron osteotomy results in lower contact stresses and osteotomy fragment displacement and may prove to be a more stable alternative to the oblique MDCO. However, these results need to be replicated in a larger cohort of patients, as well as in cadaveric studies to determine if surgeons can permit early weight-bearing with the chevron MDCO