Scientific Abstract Presentations: Research & Technology 8 Sunday, October 29 Sun, Oct 29 2:30-3:30 p.m. CDT

Purpose

Muscle viability remains the primary focus of ex vivo limb preservation. We hypothesized that genes associated with the pathophysiology of tissue injury are differentially expressed during Ex Vivo Normothermic Limb Perfusion (EVNLP) compared to static cold storage (SCS), the current gold standard for limb preservation.

Methods

Bilateral forelimbs were procured from Yorkshire pigs and randomly allocated to EVNLP (n=4) or static sold storage groups (SCS, n=4). EVNLP was carried out for up to 24 hours or until one of the termination criteria (perfusate pressure >110mmHg, weight gain ≥5%, or decrease in tissue oxygen saturation >20%) were encountered. The perfusate consisted of a colloid solution with HBOC-201 (HbO2 Therapeutics LLC, Cambridge, MA) as an oxygen carrier to generate a hematocrit of 10% -15%. Limb weight, contractility, hemodynamic parameters, perfusate electrolytes, metabolites, and gases were recorded. Skeletal muscle specimens were taken from both groups before limb procurement and at 0, 12, and 24 hours and preserved in RNAlater. Biopsies collected before limb procurement were used as controls to represent gene expression in physiologic conditions. All muscle samples were used for RNA sequencing.

Analysis of differential gene expression was performed with reverse transcriptase PCR to obtain fold changes. Samples were multiplexed and sequenced on an Illumina NovaSeq 6000 system. Gene-level counts were merged and summarized as length-scaled counts per million (CPM) with R package tximport (version 1.22.0). Graphs were made using log-transformed normalized CPM mapped reads, normalized units of gene expression were plotted, and summary statistics (mean ± standard deviation) were calculated for each gene of interest.

Alignment to the porcine genome was performed using Salmon 1.9.0. Transcripts were summarized as gene-level transcripts per million abundances with tximport. Differential expression analysis was performed using DESEQ2. Pathway enrichment by significant genes (adj-p<.05) was performed using Panther Classification System and Gene Set Enrichment Analysis.

Results

A total of 2,283 genes were differentially expressed in EVNLP (p<0.01) compared to SCS. The top enriched pathway in both EVNLP and SCS limbs was TNF-α signaling via NF-kB.

Compared to baseline, perfused limbs exhibited enrichment of pathways involved in wound healing, inflammatory response, regulation of cellular stress, negative regulation of T-cell proliferation, negative regulation of apoptotic pathways and response to fluid shear stress (adj-p <0.05). SCS limbs exhibited a different transcriptome signature, primarily enriching for positive regulation of chemotaxis and anabolic metabolism pathways.

At 6 hours, both perfused and SCS limbs expressed 62 genes differentially, as compared to time point 0. However, when comparing samples from >16 hours and 0 hours, EVNLP showed 419 differentially expressed genes, while SCS had 37 differentially expressed genes (adj-p <0.05).

Conclusion

Divergent gene expression was identified during EVNLP compared to SCS. Increased genetic transcription in the setting of EVNLP is consistent with increased metabolic activity and reactive inflammation. Identification of these evoked pathways is a necessary precursor to development of a genetic test for real-time muscle viability assessment in reconstruction and transplantation. Ongoing analyses relate the transcriptome signature with physiologic outcome parameters and markers of limb viability.

Objective Plastic surgery, specifically aesthetics, is a field where a majority of procedures are performed on female patients by a predominantly male surgical workforce. Notably, 2021 was the first cycle where more females matched into a plastic surgery residency than males according to Whisonant et al.1 As such, it is essential to minimize the gender bias of content regarding plastic surgery educational topics. We sought to identify bias in YouTube videos describing common plastic surgery search terms based on narrator gender, channel type, and language patterns.

Methods Terms were searched on YouTube using a cache-cleared browser to identify the top 30 videos for the search terms gynecomastia, hair implantation, blepharoplasty, rhinoplasty, mastopexy, and augmentation mammoplasty. These search terms were chosen to represent two male-dominated, two female-dominated, and two more gender-neutral plastic surgery procedures. Using the Linguistic Inquiry and Word Count program (LIWC) softwares, video transcripts were analyzed for 20 word categories. Video characteristics were subsequently compared by narrator gender and plastic surgery topic using Fisher's exact test, chi-square test, Student's t-test, and Welch's ANOVA. The threshold for significance was set at p < 0.05.

Results Videos regarding gynecomastia had the fewest views, likes, comments, and subscribers, whereas nose reshaping had the most views, likes, comments, and subscribers. There was a significant difference in the proportion of male speakers among channel types (p = 0.001), with medical professional personal channels having the highest relative proportion of male speakers (48 male vs. 7 female). Similarly, a significant difference in the proportion of male speakers was identified between search topics (p = 0.001), with gynecomastia (23 male vs. 2 female), hair implantation (19 male vs. 4 female), and mastopexy (20 male vs. 7 female) having fewer female speakers. Conversely, greater parity in the gender of speakers was noted for videos concerning rhinoplasty (11 male vs. 7 female) and blepharoplasty (14 male vs. 12 female). Linguistic pattern analysis through the LIWC tool demonstrated that female speakers were more likely to use language that was more authentic (p = 0.01) and express greater feeling (p = 0.012), and was less analytic (p = 0.006) and certain (p = 0.001).

Conclusion The number of male speakers outweighed female speakers, reflecting the overall male to female plastic surgeon ratio. These findings demonstrate the need for adequate female representation in both the operating room and on educational platforms, like YouTube. Patient preferences regarding surgeon choice are not well characterized and are difficult to generalize. The linguistic pattern analysis results indicate that female surgeons use more authentic and emotional language, potentially enabling them to relate more to female patients than male colleagues. Both male and female surgeons alike should be aware of the quality and characteristics of publicly-accessible patient education resources on platforms such as YouTube, particularly as social media trends may reflect patient interests and may correlate with in-person office visit discussions and procedures.

References Whisonant CT, Shahriari SR, Harrison J, et al. Evaluating the integrated plastic surgery residency match during the novel coronavirus pandemic. Cureus. 2021;13:e16988

Introduction: Diversity in medicine is crucial to ensure that important demographic characteristics of physicians reflect those of the populations they serve and increase healthcare access. The socioeconomic diversity of residents, fellows, and faculty members in any medical or surgical specialty is currently unknown making it difficult to understand socioeconomic status (SES) disparities and create programs to improve diversity. Additionally, the career trajectories of residents and faculty members who come from different SES backgrounds have not been explored. We have performed a survey-based research study to understand the SES composition and career trajectories of residents and faculty members within U.S. Plastic and Reconstructive Surgery (PRS) residency programs.

Methods: An anonymous online survey was administered to 754 recipients of U.S. PRS programs. Self-reported SES information such as household family income prior to age 18 and parental education-occupation level was collected. Career trajectory data was obtained through questions about away rotations and research productivity.

Results: Overall, 195 residents, fellows, and faculty members participated in the study, with an estimated survey respondent rate of 10.2%. Only 9.9% (10/101) of residents and fellows reported a household family income less than $40,000; however, in 2010, more than 40% of U.S. households had an annual income less than $40,000. When analyzing parental education and occupation (EO-status), 42.6% (43/101) of residents and fellows had at least one parent in an executive, managerial, or professional position with a doctorate/professional degree. Low-income and low EO-status were associated with increased utilization of federal and state assistance programs (p=0.0001) and approval for AAMC's Fee Assistance Program (FAP) (p=0.0001). Residents and fellows who identified as White were not as likely to be from low EO-status households as those who identified as Asian (OR 0.3 and p=0.015 vs. OR 2.9 and p=0.038). Residents and fellows from low EO-status backgrounds were more likely to take a gap in education (87% vs. 65.4%, p = 0.047) compared to their high EO-status peers. Notably, more current residents and fellows performed away rotations and had first-author publications during or before medical school compared to full professors (p=0.0001).

Conclusion: Understanding the backgrounds and career trajectories of trainees and faculty in medicine is essential, yet it has not been performed at the resident or faculty level. Despite its low response rate, this survey demonstrates the lack of SES diversity in PRS residency programs and identifies variation in career trajectories among those from different SES backgrounds. Incoming trainees into PRS programs continue to arise from wealthier backgrounds, of whom a significant percentage identify as White. Individuals in plastic surgery are publishing at an earlier timeline, having earlier first clinical experiences, and taking a greater number of away rotations. Large-scale research efforts are necessary to study current SES diversity and learn about the barriers encountered by trainees and educators from low-SES backgrounds in all medical and surgical specialties.

Purpose: Surgical simulation provides resident surgeons with high-fidelity operative experience to master complex procedures outside the operating room1. The osteocutaneous fibula free flap is a microsurgical procedure for mandibular defects among patients with tumors in the region. It is taught to surgical residents, but the procedure is challenging in terms of understanding and execution. This study describes an innovative approach to microsurgical education using virtual surgical planning (VSP) and free fibula cadaveric dissection for mandibular reconstruction. We also aim to review the literature for applications of VSP in a simulated environment for resident education.

Materials and Methods: A systematic review was conducted using the following databases: PubMed, Scopus, Embase, Web of Science, and Cochrane. Search terms included "virtual surgical planning", "education", curriculum", "residency", "surgical training", and "surgical simulation". An index class of junior plastic surgery residents participated in a two-day simulation experience on VSP and free fibula harvest. The first day included a didactic lecture on VSP, followed by plating of model mandibles as with VSP guides. The second day of the experience involved a fresh tissue dissection and plating of the free fibula flap in a cadaver per the VSP guide.

Results: Our search criteria identified 1869 articles, 23 of which met the inclusion criteria. Simulation model topics included free fibula flap (8.7%), orbital fracture (4.3%), and a range of procedures related to various surgical fields. Three (13.0%) models discussed procedures related to plastic surgery. Only one article applied VSP to a cadaveric model on ​​temporal bone dissection. Regarding the cadaveric free fibula model, all residents thought that their surgical technique, anatomical knowledge, and perceived confidence improved due to the simulation. All residents believed that the VSP experience with a free fibula dissection was better than standard preparation methods.

Conclusion: VSP has continued to evolve patient care in plastic surgery, but there is a unique opportunity to apply it to resident training. We demonstrated successful completion of a VSP-guided mandibular reconstruction simulation. The simulation improved resident confidence and technical skill. Early adoption of such education strategies may prove beneficial when introducing complex reconstructive procedures to early trainees.

Introduction: Recent calls for enhancing racial and ethnic diversity in the field of plastic and reconstructive surgery (PRS) have yet to achieve the desired representation of individuals who identify as underrepresented in medicine (URiMs). Defined by the AAMC as coming from Black, Hispanic, or Indigenous backgrounds, PRS has amongst the lowest percentages of URiMs compared with all other medical specialties. This study aims to reveal the racial distribution of authorship within PRS research, but also evaluate the impact that URiM mentorship has on increasing racial representation of URiM trainees contributing to PRS publications.

Methods: A cross-sectional study was performed to evaluate racial diversity among authorship in seven high-impact PRS journals over the last 12 years (2010-2022). Our team downloaded every single PRS publication in the Web of Science in the last 12 years. The data recollection provided ~25,000 publications from which ~8250 were from the U.S.A. A ~10% random sample was identified for a total of 778 publications. We analyzed distribution of first and senior author race by publication year, total distribution of race by first and senior authorship for the 7 journals, and distribution of citations by author race.

Results: The study found that across all journals, 64.48% of senior authors were white, 29.86% were Asian, 4.63% were Hispanic, and 1.03% were Black. In contrast, 59.46% of first authors were white, 32.82% were Asian, 5.15% were Hispanic, and 2.57% were Black (p=<0.0001). The study also found that the presence of minority senior authors increased the likelihood of a first author being a minority. The likelihood of a first author being Hispanic was 10.8 times more likely if there was a Hispanic senior author (p=<0.0001) , and the likelihood of a first author being Black was 26.5 times more likely if there was a Black senior author (p=<0.0001). There was no statistically significant difference in the total citation count with regards to authorship race. The Aesthetic Surgery Journal had the highest percentage of white senior authors at 73.61%, while Microsurgery had the highest percentage of Black senior authors at 8.7%. Across all journals, the percentages of white senior authors ranged from 47.83% to 73.61%, while the percentages of Asian senior authors ranged from 20.41% to 40.91%. The percentages of Hispanic and Black senior authors ranged from 0% to 8.7%. The percentages of white first authors ranged from 54.55% to 71.43%, while the percentages of Asian first authors ranged from 20.41% to 38.98%. Lastly, the percentages of Hispanic and Black first authors were lower, ranging from 0% to 8.87%.

Conclusion: Our study is the first to enumerate the scarcity of racial representation within PRS literature. It is also one of the first to quantify the positive impact that URiM mentorship has on minority trainees successfully publishing in our field. The findings of this study should prompt a multifaceted response to enhance URiM trainees into plastic surgery via various efforts which emphasize mentorship, system-level changes, and diversity recruitment.

Purpose: The purpose of this project is to evaluate gender diversity in authorship among high-impact plastic surgery journals over the past 10 years using an accurate and validated platform, Gender-API, and to identify trends and disparities in female representation as first and senior authors. The study aims to shed light on the existing gender gap in plastic surgery literature and highlight the need for future efforts to address this gap and promote gender diversity in the field while ensuring optimal patient care. This is the first project to recollect this information and provide insights into the state of gender diversity amont high-impact plastic surgery journals authorship.

Methods: A cross-sectional study was performed to evaluate gender diversity among authorship in seven high-impact journals over the last 10 years. The prevalence of female, first and senior, authorship publications were examined using a platform, Gender-API, an accurate-validated-interface program that assigned binary genders to authors based on their first name, full name, and location.

Results: Among the journals analyzed,23.1% of all publications had female first authors, which was generally, one third to one fourth the frequency of male first authorship. Across journals the Aesthetic Surgery Journal had 20.6% female first authors; the Annals of Plastic Surgery and Plastic and Reconstructive Surgery, both were 22.9% female, the Journal of Craniofacial Surgery were 21.1% female. The Journal of Reconstructive Microsurgery had 20.5% female first authorship: while Microsurgery had 15.3%. Each journal had a significantly lower percentage of female first authors versus male first authors except the Cleft Palate-Craniofacial Journal which had near parity with a total of 49.8% female first authors. During the 10-year period there was significantly lower number of females, senior authors when compared to male senior authors; 15.1% of all senior authors were female. Female senior author groups comprised 13.4 % in the Annals of Plastic Surgery 14.3% authors in the Plastic and Reconstructive Journal, 14.6 % of the authorship in the Aesthetic Surgery Journal, and 15% of authors in the Journal of Craniofacial surgery. The frequency is somewhat less at 9.32% of all authors published in Microsurgery, and 10.6% of authors whose works were published in the Journal of Reconstructive Microsurgery. Between 2012 and 2021, overall, the percent of female first authors increased from 18.4% in 2012 to 29.5% in 2021. The percent of female senior authors increased from 12.5% in 2012 to 16.1% in 2021. Across all journals, there was an increase in the proportion of female first authors and female senior authors from 2012-2021.

Conclusion: Despite women comprising over half of medical students and PRS residents, their representation as authors in plastic surgery literature is lower than other specialties due to barriers such as lack of mentors, family responsibilities, and institutional bias. This research project is the first to provide a comprehensive analysis of gender diversity among authorship in seven high-impact PRS journals over the past decade, highlighting significant gender disparities and the urgent need for interventions to promote diversity for first and senior authors.

References:

1. Ysseldyk, R., et al., A Leak in the Academic Pipeline: Identity and Health Among Postdoctoral Women. Front Psychol, 2019. 10: p. 1297. 2.Sugrue, C.M., C.W. Joyce, and S.M. Carroll, Levels of Evidence in Plastic and Reconstructive Surgery Research: Have We Improved Over the Past 10 Years? Plast Reconstr Surg Glob Open, 2019. 7(9): p. e2408.
2. Silvestre, J., et al., Gender Authorship Trends of Plastic Surgery Research in the United States. Plast Reconstr Surg, 2016. 138(1): p. 136e-142e.
3. Llorens, A., et al., Gender bias in academia: A lifetime problem that needs solutions. Neuron, 2021. 109(13): p. 2047-2074.
4. Hart, K.L., et al., Trends in Female Authorship in High Impact Surgical Journals Between 2008 and 2018. Ann Surg, 2022. 275(1): p. e115-e123.