47.17 An Analysis of Factors Resulting in Thyroid Reoperations

Posted on January 31, 2019

T. Longoria Dubocq1, M. Serpa1, A. Lugo1, E. Santiago1, A. Gonzalez1, W. Mendez-Latalladi1  1University Of Puerto Rico School Of Medicine,Endocrine Surgery Section. Department Of Surgery,San Juan, Puerto Rico, USA

Introduction: Thyroid surgery has been practiced for many years by General Surgeons to treat benign and malignant disease. However, the development of new surgical sub-specialties have demonstrated that treating thyroid disease at a high volume center (HVC) improves outcomes in this kind of patients. Many studies have showed that thyroid reoperations have a higher complication rate when compared to single thyroid surgery. We studied the incidence of causes for surgery reoperation and if whether the initial surgery was performed at a low volume center (LVC) or HVC.

Methods: This is a retrospective study were we analyzed all thyroid reoperations from 2013 to 2018 at a HVC institution. HVC was defined as hospital that performed more than 100 thyroid surgeries per year and surgeons with more than 25 thyroid surgeries per year. Data from previous surgeries, and reasons for reoperation was gathered and evaluated statistically. Reoperation was defined as a patient who had thyroid surgery with previous history of thyroid surgery. Patients were also divided into two groups depending on where their first surgery took place: LVC (Group 1) or HVC (Group 2). SPSS statistical software and Pearson’s Chi-Square test used for analysis and comparison. To establish statistical significance a p-value ≤ 0.05 was utilized.

Results: We examined 786 records of which 105 (7.49%) had undergone a previous thyroid surgery. Five were excluded due to lack of information. There were 86% (86/100) females and 14% (14/100) male in our study. The most common overall reason for re-operation was completion thyroidectomy due to previous lobectomy pathology positive for cancer 35% (35/100); followed by recurrence of malignant disease 34% (34/100) overall. Reoperation for benign disease was 23% (23/100) overall. Group 1 consisted of 40% (40/100) of patients while Group 2 had 60% (60/100) of patients. In Group 1, the most common reason for reoperation was malignant disease recurrence with 47.5% (19/40). In Group 2, the incidence of malignant disease recurrence occupied 25% (15/60) of the cases which was significant when compared between the two groups (p=0.001). Group 2 most common reason for reoperation was a malignant lesion requiring completion thyroidectomy with 53.33% (32/60).

Conclusion: The most common reason for reoperative thyroid surgery was a previous lobectomy with incidental malignancy and indications for a completion thyroidectomy. When the first surgery was performed in a LVC, the most common reason for reoperation was recurrence of malignancy.

47.16 Does thyromegaly with tracheal deviation or substernal extension pose high risk of acute airway compromise?

Posted on January 31, 2019

Y. Qudah1, J. Crystal1, J. Wade1, T. Davidov1  1Robert Wood Johnson – UMDNJ,General Surgery,New Brunswick, NJ, USA

Introduction:   Thyromegaly with tracheal deviation and substernal extension is an indication for surgery in part because of concerns over airway compromise.  However, the exact risk is unclear.

Methods:   CT scans of the neck or chest from 2009-2017 performed at a single hospital were queried for findings of thyromegaly with substernal extension, tracheal deviation, or tracheal compression. The charts of these patients were retrospectively reviewed to determine whether acute airway compromise with sudden intubation or urgent surgical intervention was required.

Results: A total of 682 scans were queried, revealing 209 patients whose scans demonstrated  substernal extension or tracheal deviation or compression. Of 209 patients, 125 patients (60%) were asymptomatic with CT findings incidentally discovered.  Eighty-four patients (40%) presented with symptoms including dyspnea, dysphagia, chest pain, neck pain, or visible neck mass.  Nineteen patients that had these CT findings required intubation during their hospital stay, of which 18 intubations were emergent.  Of these 19 patients, 18 had confounding cardiopulmonary problems. No patients required cricothyroidotomy or urgent tracheostomy. There were no mortalities related to sudden airway compromise.  Five patients progressed to surgery, one of whom required sternotomy.

Conclusion: While thyromegaly with substernal extension or tracheal deviation may an indication for thyroidectomy in part to prevent sudden airway compromise, the majority of patients with these CT findings are asymptomatic and only rarely do these patients sustain an airway emergency requiring an intervention.

 

47.15 Si vs. Xi Robot for Adrenalectomy: A 10-year experience

Posted on January 31, 2019

A. Lucy1, E. Malone1, J. Richman1, J. Owen1, J. R. Porterfield1  1University Of Alabama at Birmingham,Surgery,Birmingham, Alabama, USA

Introduction: Over the last decade, robotic adrenalectomy has been increasingly used for surgical management of adrenal masses. The da Vinci Xi robot was introduced in 2014 as a more versatile upgrade to their Si robot with the goal of promoting OR efficiency and multi-quadrant access. The specific benefits of the Xi robot have only been addressed in a limited number of specialties and procedures. The aim of this study was to compare the outcomes of the Xi vs. the Si system for robotic adrenalectomy in a high-volume center.                                                         

Methods: All patients at a single institution undergoing adrenalectomy between June 2008 and May 2018 were captured prospectively (n=515). We excluded patients who had an adrenalectomy by a non-robotic approach and who were <18 years old (n=212). Demographic, clinical, pathological, and operative variables were collected from electronic medical records. An adjusted negative binomial regression model was used to examine the change in total operating room time by robot type adjusting for all covariates significantly associated with room time in bivariate tests. These included diabetes, facility (main hospital vs. outpatient surgery center), robot type, and final pathology. Chi-square or Fisher's Exact Tests and t-tests were used to examine differences in categorical and continuous variables by robot type.

Results: Robot type was documented for 99% of 212 cases (n=209). There were no significant differences in patient demographics or preoperative comorbidities by the robot type. Median total room time using the Xi was 215 minutes (IQR: 190-254) vs. 235 (IQR 203-279) for the Si system (p=0.03). Other perioperative and pathological variables were similar. In adjusted models, total room time was 11% longer for diabetic patients vs. non-diabetics (IRR 1.11, 95% CI: 1.03-1.20), procedures done at our outpatient surgery center were 22% shorter vs. our main facility (IRR 0.78, 95% CI 0.68-0.89), and Xi robot procedures were 9% shorter than those done with the Si robot (IRR 0.91, 95% CI 0.83-0.99).

Conclusion: In adjusted analyses, the Xi robot has shorter adrenalectomy times compared to the Si robot. We attribute this decrease in operative time to the improved instrumentation, ease and efficiency in docking and patient positioning. More multi-institutional studies with larger groups of patients are needed to document the effect of advancing technology and carefully track and publish outcomes.

 

47.09 Epidural anesthesia is safe in open resection of pheochromocytoma and abdominal paraganglioma

Posted on January 31, 2019

D. Wiseman1, J. McDonald1, D. Patel1, E. Kebebew3, K. Pacak2, N. Nilubol1  1National Cancer Institute,Bethesda, MD, USA 2National Institute of Child Health and Human Development,Bethesda, MD, USA 3Stanford University,Surgery,Palo Alto, CA, USA

Introduction:

The most common side effect of epidural anesthesia (EA) is hypotension. Because hypotension frequently occurs after a removal of pheochromocytoma-paraganglioma (PPGLs) from the alpha-adrenergic blockade and the abrupt reduction of catecholamine production, we aimed to determine if EA is associated with an increased risk of postoperative hypotension and complications from postoperative fluid overload.

Methods:

We performed a retrospective review of a prospectively collected cohort of patients who underwent open resections of PPGLs from 2009-2018.  The EA infusion started before patient transfer to ICU. Clinical characteristics, tumor burden, and perioperative parameters were analyzed by the use of EA. The primary endpoint was postoperative hypotension.

Results:

Of 66 patients who underwent open resections of PPGLs, 52 (78.8%%) received EA. No differences in patient demographics and clinical characteristics were found by the use of EA except the significantly lower rate of EA used in patients with von Hippel-Lindau disease due to the presence of spinal hemangioblastoma (0% vs. 82.5%, p=0.008) and a higher rate of EA use in patients undergoing reoperation (85.7% vs. 58.8%, p=0.035). We found that postoperative hypotension was common following open resections of abdominal PPGLs (56.9%). However, there was no difference in the rates of postoperative hypotension by the use of EA (58.8% in EA group vs. 50.0% in non-EA group, p=0.561), the need for postoperative vasopressor (p=1.00) or diuretics (p=0.111), postoperative weight gain (p=0.436), hypoxia (p=0.703), or the volume of IV fluid in the first 24 hours postoperatively (p=0.903). EA was stopped because of postoperative hypotension in 13.6% of patients.

Conclusion:

Although postoperative hypotension is common after open resection of PPGLs, EA is safe as it was not associated with increased risk of postoperative hypotension or fluid overload.
 

46.10 A Microfluidic Study of Non-Glycemic Effects of Metformin on Hyperglycemia-stress exposed endothelium

Posted on January 31, 2019

J. V. Martin1, D. M. Liberati1, L. N. Diebel1  1Wayne State University,Surgery/School Of Medicine,Detroit, MI, USA

Introduction: Stress related hyperglycemia is associated with poor outcomes in trauma and critically ill patients. Correction of hyperglycemia may improve clinical outcomes; however tight glycemic control with insulin may lead to hypoglycemic episodes and resultant glucose variability. Metformin has demonstrated efficiency in hyperglycemia treatment in burn and non-diabetic coronary bypass surgery patients. These effects may be partly due to non-glycemic effects including a beneficial effect on endothelial function. We have shown that acute hyperglycemia exacerbates trauma induced endothelial and glycocalyx injury in an in vitro model. We therefore studied the effect of metformin on endothelial injury in a biomimetic model of hemorrhagic shock using a microfluidic device.

Methods: Human umbilical vein endothelial cell (HUVEC) monolayers were established and perfused in a microfluidic device. Perfusion conditions included media alone (control), media + 80 or 200 mg/dl glucose with or without hypoxia-reoxygenation (H/R) + epinephrine (Epi) to mimic the microcirculation following hemorrhagic shock (HS). Metformin (50µM) was added after glucose exposure. Markers of endothelial glycocalyx degradation were syndecan-1 (syn-1) and hyaluronic acid (HLA) shedding. Endothelial cell activation markers included soluble thrombomodulin (sTM), and angiopoietin-1 and 2 concentrations in the perfusate. Reactive oxygen species (ROS) and inducible nitric oxidase synthase (iNOS) generation were measured using fluorescent imaging.

Results: See Table.

Conclusion: Metformin ameliorated stress hyperglycemia effects on glycocalyx and vascular barriers in a biomimetic model of the microcirculation following HS. These effects may be related to decreased ROS and iNOS generation. Microfluidics may be useful to study the endotheliopathy of trauma and HS. 

 

45.20 Heat Shock Protein 70 modulates Dendritic Cell Function in Tumor Microenvironment

Posted on January 31, 2019

B. Giri1, A. Ferrantella1, P. Sharma1, V. Sethi1, S. Modi1, Z. Malchiodi1, B. Garg1, S. Ramakrishnan1, S. Lavania1, S. Banerjee1, A. Saluja1, V. Dudeja1  1University Of Miami,Surgery,Miami, FL, USA

Introduction: Dendritic cells (DCs) are an up and coming technique for immune cell vaccination in tumor control strategies. We evaluated whether absence of heat shock protein 70 in dendritic cells altered their antitumor properties.

 

Methods: Dendritic cells from tumor bearing mice from either WT or HSP70-/- mice were selected by pan dendritic cell isolation kit. Then they were inoculated in mice with WT or HSP70-/- background and then given a tumor challenge of pancreatic cancer with KPC cells. In another experiment, WT or HSP70-/- dendritic cells were exposed to tumor cell lysates derived from the mouse pancreatic cancer cell line, KPC, in vitro.

 

Results: Tumors that were formed in WT mice receiving HSP70-/- DC were smaller than those receiving WT Dendritic cells. Overall vaccination with DC decreased tumor formation rate in both WT and KO mice but the decrease in tumor size was greater when HSP70-/- DC were implanted. Similarly, HSP70-/- dendritic cells had greater expression of anti-tumorigenic MHCII peptide on their surface when they were exposed to tumor lysates from KPC cells suggesting that HSP70 deficient DCs were more adept at mounting an anti-tumor immune effect. 

 

Conclusion: HSP70 modulates dendritic cell function in the immune response against cancer.

45.07 Role Of Epigenetic Alteration In CD8+ T-cells Associated With Hepatocellular Carcinoma

Posted on January 31, 2019

T. M. Dawud1, E. Kimchi1,2, J. Kaifi1,2, G. Li1,2, D. Avella1,2, K. Staveley-O’Carroll1,2  1Department of Surgery, University Of Missouri Columbia,Columbia, MO, USA 2Ellis Fischel Cancer Center,Columbia, MO, USA

Introduction:

Background: Hepatocellular cancer (HCC) is the second leading cause of cancer-related mortality worldwide. The majority of patients are diagnosed at late-stage. For these patients, curative approaches such as surgical resection, orthotopic liver transplantation and local, percutaneous tumor ablation are unavailable. Therefore, palliative treatment options play an important role in the management of patients with HCC. Recently, immunotherapy has been approved by the US FDA to treat the patients who are resistant to sorafenib, the only FDA-approved chemotherapeutic treatment. However, objective therapeutic response is only seen in about 14% patients. Elucidating the underlying mechanisms is helpful to improve and develop effective now immunotherapy. 

Hypothesis: We hypothesize that epigenetic regulation is showing as one of mechanisms to mediate exhaustion of CD8+ T-cells in HCC by inducing genomic DNA methylation in cytokine genes. 

Methods: In terms of our established strategy, we made a clinically relevant HCC murine model by combining injection of carbon tetrachloride with splenic injection of oncogenic hepatocytes from SV40 T antigen transgenic mice. We immunized these large tumor-bearing mice and wild type mice with tumor-specific antigens. The tumor-infiltrating leukocytes were isolated from these mice with large tumors. Some cells were used to measure cytokine production in CD8+ T cells. Other cells were used to purify PD1+ CD8+ T cells and PD1– CD8+ T cells by sorting with flow cytometry. The mRNAs and genomic DNAs was extracted from these purified cells for detecting mRNA expression of IFN-γ and TNF-α as well as whole genome sequencing after bisulfite conversion. Syngeneic wild-type C57BL/6J mice were used as controls.

Results: The decreased production of IFN-γ and TNF-α was detected in CD8+ T cells from HCC-bearing mice compared to cells from wild-type mice. Whole genome bisulfite sequencing showed significant methylation difference in PD1+ CD8+ T cells between HCC-bearing mice and wild-type mice. In addition, the methylation difference was detected in PD1+ CD8+ T cell and the PD1– CD8+ T cell population isolated from HCC-bearing mice.

Conclusions And Future Directions: Tumor growth results in epigenetic modification and alteration in the genome of CD8+ T cells, suggesting the possible mechanism of epigenetic regulation in tumor-induced exhaustion of CD8+ T cells. We will treat HCC-bearing mice with demethylation agents to explore its therapeutic effect. In addition, we will evaluate if combination of demethylation will be helpful to improve other immune-based therapeutic strategies in HCC control.

43.07 Correlation between Altmetric Score and Citations in Pediatric Surgery

Posted on January 31, 2019

J. Chang1, N. Desai1, A. Gosain1,2  1University of Tennessee Health Science Center,Division Of Pediatric Surgery, Department Of Surgery,Memphis, TN, USA 2Children’s Foundation Research Institute, Le Bonheur Children’s Hospital,Division Of Pediatric Surgery,Memphis, TN, USA

Introduction:  The impact of a scientific manuscript has traditionally been measured by the impact factor of the journal it is published in and the number of times it is cited. However, citations have a lag period before the true impact of a manuscript can be determined. The Altmetric score has emerged as a measure of the digital dissemination of a scientific manuscript across multiple platforms, including Tweets, Facebook likes, and other social & popular media mentions. We hypothesized that Altmetric score would correlate with citations and journal impact factor in Pediatric Surgery.

Methods:  Using the previously identified the fourteen core journals of Pediatric Surgery, the top ten most-cited articles from each of these journals were identified for the year 2012, allowing for 5+ years of follow-up. For each article, we determined the number of times cited and the Altmetric score. For each journal, the 2012 impact factor and year in which the journal’s Twitter account was established was determined. Descriptive statistics and Pearson’s correlation coefficients were determined using GraphPad PRISM software.

Results: Citation information for n=140 articles was obtained. Articles were cited 56159 times (Median 192, IQR 83-403). Median Altmetric score was 8 (IQR 2-58). Citations correlated strongly with journal impact factor (r=0.82, p<0.0001). Altmetric score did not correlate with journal impact factor (r=0.08, p=0.32). Altmetric score weakly correlated with citations (r=0.189, p=0.03) with wide variability amongst journals (range -0.21 to 0.96). When analyzed on an individual journal basis, decreasing age of a journal’s Twitter account resulted in decreasing correlation between Altmetric score and citations (r=-0.299, p=0.0003).

Conclusion: This study is the first to link traditional bibliometric measures with newer measures of digital dissemination for publications in Pediatric Surgery. While the Altmetric score of the top cited manuscripts did not correlate with journal impact factor, it did weakly correlate with citations. Interestingly, this correlation was strongest for journals with well-established Twitter accounts, indicating that, over time, the Altmetric score may emerge as a tool to predict future citations. Currently, the Altmetric and traditional bibliometric measures appear to have distinct, but complementary roles in measuring dissemination and impact of scientific manuscripts in Pediatric Surgery.

43.03 Timing of Surgery and Internal Medicine Clerkships and Surgery Shelf Exam Scores

Posted on January 31, 2019

A. Phares1, C. Sauder1, E. Salcedo1, D. Leshikar1, C. Irwin1, G. Middleton2, H. Phan1  1University Of California – Davis,Department Of Surgery,Sacramento, CA, USA 2University Of California – Davis,Office Of Medical Education,Sacramento, CA, USA

Introduction:
The third-year of medical school is a stressful time for students as they transition from the classroom to the clinics and wards. Students strive to perform well clinically with their patients and teams as well as academically on their assignments and exams. Many students believe that rotation sequence effects their success. At UC Davis, students interested in surgery believe that completing the internal medicine (IM) clerkship before the surgery clerkship will help improve their surgery shelf exam scores. We hypothesized, despite our students’ impressions, that students who completed the IM clerkship prior to the surgery clerkship did not receive higher surgery shelf examination scores than the students who did not.

Methods:
Deidentified academic data for all third-year UC Davis School of Medicine medical students from 2012-2017 were collected. Data included undergraduate GPA, MCAT scores, USMLE Step 1 scores, and NBME shelf exam scores for surgery. Students who did not complete all six core clerkships during the standard third-year time frame were excluded. The average shelf exam scores were analyzed using a 2-tailed t-tests both in aggregate and by individual rotation slot. Z-scores were also calculated for the average shelf exam scores by rotation slot.

Results:
Data from 424 students were included in the study. 214 students completed the IM clerkship before the surgery clerkship and 206 did not. Average undergraduate GPA, MCAT scores, and USMLE Step 1 scores were compared between the two groups, and no significant differences were found. In aggregate, average shelf exam scores of students who completed the IM clerkship prior to the surgery clerkship were significantly higher than those of students who did not (77.0% vs 73.8%, p value < 0.001). Additionally, average shelf exam scores for all students increased over the academic year. When the average shelf exam scores for the two groups were analyzed by rotation slot, no significant difference was found between the two groups (Table 1).

Conclusion:
When the shelf exam scores were analyzed in aggregate, students who completed the IM clerkship before the surgery clerkship scored higher on their surgery shelf exams. However, the surgery shelf scores were higher as the academic year progressed. Students who completed the surgery clerkship later in the academic year were more likely to have completed the IM clerkship already. When examining the two groups by rotation slot, we found no difference between the students who had already completed the IM clerkship and those who had not. These data suggest that students' scores on the surgery shelf exam are related to experience gained and are independent of the timing of the IM rotation in relation to the surgery rotation.
 

38.10 Opioid Prescribing Practices in Pediatric Surgeons: Changing in Response to the Opioid Epidemic?

Posted on January 31, 2019

K. T. Anderson1,7, M. A. Bartz-Kurycki1,7, D. M. Ferguson1,7, M. Raval5,7, D. Wakeman4,7, D. Rothstein6,7, E. Huang2,7, K. Lally1,7, K. Tsao1,7  6University of Buffalo,Pediatric Surgery,Buffalo, NY, USA 1McGovern Medical School at UTHealth and Children’s Memorial Hermann Hospital,Pediatric Surgery,Houston, TX, USA 2University of Tennessee Health Sciences Center, Le Bonheur Children’s Hospital,Pediatric Surgery,Memphis, TN, USA 4University of Rochester School of Medicine and Dentistry,Surgery,Rochester, NY, USA 5Northwestern University, Feinberg School of Medicine,Pediatric Surgery,Chicago, IL, USA 7Pediatric Surgical Research Collaborative,USA, USA, USA

Introduction: The crisis of opioid misuse in the United States has led healthcare providers to re-evaluate their prescribing practices and pain management strategies. This study aimed to describe the perception of pediatric surgeons and their self-reported prescription practices for common general pediatric surgical procedures.

Methods: Pediatric surgeons in the Pediatric Surgical Research Collaborative and one non-member group were surveyed. Respondents were asked about their usual (>50% of the time) practices for pain management perioperatively (during or immediately after surgery) and at discharge in four common pediatric surgery operations: an infant after inguinal hernia repair, a young child after umbilical hernia repair, a school-aged child after laparoscopic appendectomy, and a teenager after laparoscopic cholecystectomy. Descriptive statistics and logistic regression were used for analysis.

Results: There were 171 respondents (61% response rate) with a median of 10 years in practice (IQR 4.5-20). The majority of pediatric surgeons responded that the opioid epidemic is an issue in pediatric surgery (61%), their prescribing practices matter (79%) and that they have changed their opioid prescribing patterns (80%). Almost ¼ of surgeons had witnessed opioid abuse problems in their practice, with 17% reporting treating pediatric patients with opioid abuse problems. Most surgeons prescribed opioids in the treatment of surgical pain perioperatively and at discharge for school age children undergoing a laparoscopic appendectomy or a teenager undergoing laparoscopic cholecystectomy (Table). Opioid prescribing was less common in younger children. Presence or use of a hospital or state prescription monitoring system was not associated with opioid prescribing. Increasing years in practice, however, was associated with greater odds of opioid prescribing at discharge in infants (OR 1.07, 95% CI 1.02-1.12).

Conclusions: Most pediatric surgeons believe that opioid misuse is an important issue and have changed their practices to address it. Nevertheless, a majority of surgeons prescribe opioids to school age and older children after common surgical procedures. 
 

33.06 Adrenal Venous Sampling vs. Imaging for Surgical Decision Making in Primary Hyperaldosteronism

Posted on January 31, 2019

J. Shank1, N. Nagarajan1, B. Holly2, A. Mathur1, J. Canner1, J. D. Prescott1  1Johns Hopkins University School Of Medicine,Department Of Surgery,Baltimore, MD, USA 2Johns Hopkins University School Of Medicine,Department Of Radiology And Radiological Sciences,Baltimore, MD, USA

Introduction:
Adrenal venous sampling (AVS) is the gold standard test for lateralizing aldosterone hypersecretion/identifying bilateral disease in cases of primary hyperaldosteronism. Though efficacious, AVS is expensive, invasive, requires significant technical expertise and is not universally available. The utility of less expensive, less morbid imaging techniques for disease lateralization has been limited by relatively poor associated sensitivity and specificity. Nonetheless, medical imaging technology is continually improving, making periodic reassessment of imaging lateralization accuracy, relative to AVS, necessary.

Methods:
A retrospective review was performed to identify patients who underwent AVS between July 1st 2003 and April 30th 2015 at our academic tertiary care center. Patients were excluded if AVS was not performed for hyperaldosteronism, if CT and/or MRI adrenal imaging was not done and if disease management was unknown. Data were extracted for demographic, clinical, biochemical and treatment variables. Continuous variables were summarized using medians and interquartile range (IQR). Binary/categorical variables were summarized as proportions.

Results:
A total of 204 AVS patients were identified, of whom 112 met inclusion criteria. Overall, 71 patients underwent unilateral adrenalectomy. Among the 53 patients in this group having concordant AVS and imaging findings, postoperative serum aldosterone values were available for 34, with biochemical cure achieved in 32 (94.1%). When AVS and imaging were discordant (n=14), AVS lead to surgical cure in 77.8 % of patients, none of whom would have been referred for surgery on the basis imaging findings alone (bilateral adrenal nodules). When discordant, 4 patients underwent surgery based on imaging postoperative aldosterone was only available for 1 patient who showed biochemical cure. Among the 41 patients treated medically, concordance was 48.8%, with discordance resulting primarily from unilateral imaging findings in the context of bilateral AVS results. Overall, an imaging only-based management plan was, or would have been, incorrect in 28.6% of the cohort (inappropriate surgery or inappropriate medical management).

Conclusion:
Our findings identify high discordance rates between AVS and contemporary abdominal imaging techniques when assessing disease laterality among patients diagnosed with primary hyperaldosteronism. AVS thus remains critical to accurate clinical decision-making for these patients.
 

33.05 Specific Growth Rate as a Predictor of Survival in Pancreatic Neuroendocrine Tumors

Posted on January 31, 2019

J. J. Baechle1, P. M. Smith2, M. Tan2, C. Bailey2, C. Solorzano2, A. G. Lopez-Aguiar3, M. Dillhoff4, E. W. Beal4, G. Poultsides5, E. Makris5, F. G. Rocha6, A. Crown6, C. Cho7, M. Beems7, E. R. Winslow8, V. R. Rendell8, B. A. Krasnick9, R. Fields9, S. K. Maithel3, K. Idrees2  1Meharry Medical College,School Of Medicine,Nashville, TN, USA 2Vanderbilt University Medical Center,Department Of Surgery,Nashville, TN, USA 3Emory University,Department Of Surgery,Atlanta, GA, USA 4Ohio State University,Comprehensive Cancer Center,Columbus, OH, USA 5Stanford University Medical Center,Palo Alto, CA, USA 6Virginia Mason Medical Center,Seattle, WA, USA 7University Of Michigan,Hepatopancreatobiliary And Advanced Gastrointestinal Surgery,Ann Arbor, MI, USA 8University Of Wisconsin,School Of Medicine And Public Health,Madison, WI, USA 9Washington University,School Of Medicine,St. Louis, MO, USA

Introduction:  Pancreatic neuroendocrine tumors (PNETs) are often indolent, but rapidly progressing variants have been reported. To better inform prognosis and treatment decisions, improved understanding of patients at-risk for rapidly progressing PNETs is critical, particularly for patients with small PNETs who may be candidates for expectant management under current treatment guidelines. Specific growth rate (SGR) has been demonstrated in multiple malignancies to be predictive of overall and disease-free survival, but SGR has not been examined in PNETs. The aim of this study is to determine the predictive value of SGR on oncological outcomes in patients with PNETs.

Methods:  A retrospective cohort study of adult patients who underwent surgical resection of PNET from 2000-2016 was performed utilizing the multi-institutional U.S. Neuroendocrine Study Group database. Patients with PNET and more than one pre-operative cross-sectional imaging study at least thirty days apart were included in our analysis. The tumor SGR (% growth/day) was calculated using the tumor diameters measured on initial (Di) and final (Df) pre-operative imaging utilizing the previously published equation: SGR = 3ln(Di-Df)/ΔT. Patients with a SGR above the ninetieth percentile were termed “high SGR” and the remaining patients were termed “low SGR”. Overall survival (OS) was analyzed by Kaplan-Meier method and log-rank test. Cox proportional hazard models were used to assess the impact of SGR on OS after adjusting for patient and tumor characteristics. 

Results: Of the 1,247 PNET patients who underwent resection, 288 (23%) had two or more pre-operative cross-sectional imaging studies at least 30 days apart. High SGR was associated with higher T Stage at resection (p=0.01), shorter doubling time (p<0.01), and elevated HbA1c (p=0.01). Patients with high SGR also had significantly decreased 5-year OS and disease-specific survival (DSS) compared to those with low SGR (63 vs 80%, p=0.01, Figure 1a; 72 vs 86%, p=0.03, Figure 1b). In patients with small (≤2cm) tumors, high SGR predicted lower 5-year OS (85 vs 91%, p=0.01, Figure 1c). When examining all patients by multivariate analysis controlling for T, N, M stage and HbA1c, high SGR was independently associated with worse OS (Hazard Ratio 2.67, 95% Confidence Interval 1.05 – 6.84, p=0.04).

Conclusion: High SGR in PNETs, including small tumors (<2cm), is associated with worse survival. High SGR can potentially be utilized as a useful marker in the clinical decision process particularly when weighing close observation versus surgical resection in patients with small PNETs.

 

30.03 Effect of Portable, In-Hospital ECMO on Clinical Outcomes

Posted on January 31, 2019

N. Wall1, J. E. Tonna1, A. Koliopoulou1, K. Stoddard1, S. G. Drakos2, C. H. Selzman1, S. H. McKellar1  1University of Utah,Cardiothoracic Surgery,Salt Lake City, UT, USA 2University Of Utah,Cardiovascular Medicine,Salt Lake City, UT, USA

Introduction:
The time between the onset of cardiogenic shock and initiation of mechanical circulatory support is inversely related to patient survival. The delays inherent to transporting a patient to the operating room (OR) for initiation of extracorporeal membrane oxygenator (ECMO) could prove fatal. A primed and portable VA ECMO system would allow initiation of ECMO in various locations within the hospital, including the emergency department for patients with out of hospital cardiac arrest (OHCA). We hypothesized that an in-hospital, portable VA ECMO program would improve outcomes for patients in cardiogenic shock.

Methods:
We retrospectively reviewed our institutional experience with VA ECMO based on two periods: the first was from the beginning of our VA ECMO program (2009), and the second from initiation of our primed and portable in-hospital ECMO system (April 2015). The primary end point was patient survival to discharge.

Results:
A total of 137 patients were placed on VA ECMO during the study period; n= 66 (48%) and n=71 (52%) before and after program initiation, respectively. The average age was 55 years old, with 69% being male. Non-ischemic cardiomyopathy was the etiology of heart failure in 55% of patients. There were no significant differences in demographics between the two groups. In the second era, the proportion of OR ECMO initiation decreased significantly (from 92% to 49%, P<0.01) as more patients received ECMO in other hospital units, including the emergency department for OHCA (P<0.01). Additionally, while the proportion of patients receiving central vs peripheral cannulation did not change, peripherally cannulated patients in the second era received smaller arterial cannulae (21 +/- 3.6 vs 17 +/- 3.1 French, P<0.01), and a greater proportion of these patients received distal limb perfusion cannulae (21% vs 45%, P=0.02). Survival to ECMO removal was similar for both groups (53% and 52%), while survival to hospital discharge was numerically higher for the current era (30% vs 42%, P=0.1). Finally, we observed a significant increase in clinical volume since initiation of the in-hospital, portable ECMO system from an average of 10 patients/year to 26 patients/year (P<0.01).

Conclusion:
After developing an in-hospital, primed and portable VA ECMO system, we observed increased clinical volume with more ECMO being initiated in non-OR settings. We conclude that more rapid deployment of VA ECMO may extend the treatment eligibility to more patients and improve patient outcomes.
 

29.08 Shared Decision-making for Unilateral Breast Cancer Patients Choosing between CPM and UM

Posted on January 31, 2019

J. Huang1, A. Chagpar1  1Yale University School Of Medicine,New Haven, CT, USA

Introduction:

Choosing between contralateral prophylactic mastectomy (CPM) and unilateral mastectomy (UM) is a personal decision, but the patient’s surgeon may influence this. We sought to determine how different patient-doctor communication strategies play into the decision-making process.

Methods:

Female unilateral breast cancer patients who had a mastectomy at a large academic institution were approached to participate in a survey regarding patient-physician communication and their decision between CPM and UM. Patient satisfaction with decision was measured using the 5-point Satisfaction with Decision (SWD) scale (higher = more satisfied). Non-parametric statistics were performed using SPSS version 24.

Results:

100 (91.7%) of 109 patients approached completed the survey and were included in this cohort; the median age was 49.5 years (range 29-82). 54 patients chose to undergo CPM (54%). 33 patients (33%) reported being recommended UM, 6 patients (6%) reported being recommended CPM, and 61 patients (61%) reported that their doctors employed shared decision-making (SDM), i.e., made no strong recommendation either way. The majority of patients who stated their doctors recommended UM chose UM (78.8%); similarly, 83.3% of those who stated their doctors recommended CPM chose CPM. Of the 39 patients whose doctors recommended a surgery, 8 patients (20.5%) did not follow their doctor’s advice. These patients were equally as satisfied with their decision as those who did follow their doctor’s advice (p=0.441). Compared to patients that followed their doctor’s advice, patients who did not tended to use a 2nd physician’s opinion (38.7% vs. 0%, p=0.042) as well as photos of cosmetic results (37% vs. 6.5%, p=0.049) in their decision-making process. There was no difference in age, race, education, insurance type, or income between patients who followed their doctor’s advice versus those who did not (p>0.05). Patients who reported engaging in SDM tended to choose CPM (68.3% vs. 30.8%, p<0.001). The mean SWD score of the entire cohort was 4.80 out of 5.00 (range 3.17-5.00). Patients who did not engage in SDM were similarly satisfied with their decision as those who did engage in SDM (mean SWD score 4.77 vs. 4.83, p=0.286). In terms of patient reported preferences for patient-physician communication, 12 patients (12%) preferred the doctor to provide a recommendation, 7 (7%) preferred to make the decision on their own, and 81 (81%) preferred to engage in SDM. Race, education, insurance type, income, and age did not differ between types of preferred communication strategies (p>0.05).

Conclusion:

When the physician provides an initial recommendation between UM and CPM, patients tend to follow it, while patients who engaged in SDM tend to choose CPM. While most patients state that they prefer to have physicians engage in SDM, patients were equally as satisfied with their surgical decision whether they engaged in SDM or not.

29.07 Increased APOBEC3C-H Gene Expression is Associated with Improved Outcome in Breast Cancer

Posted on January 31, 2019

M. Asaoka1,2, S. K. Patnaik1, A. L. Butash1, E. Katsuta1, T. Ishikawa2, K. Takabe1,2  1Roswell Park Cancer Institute,Surgical Oncology,Buffalo, NY, USA 2Tokyo Medical University,Department Of Breast Surgery And Oncology,Shinjuku, Tokyo, Japan

Introduction:

APOBEC enzymes are known as strong mutagenic factors, particularly in breast cancer. APOBEC3B (A3B) gene expression is significantly increased in breast cancer and associated with tumor mutation load and intra-tumor heterogeneity. The relevance of the other APOBEC3s (A3A, C-H) is not yet clear in breast cancer. Therefore, we analyzed these genes, looking at their association with survival, mutations, and immune activity.

Methods:

We collected gene expression data for primary tumors (1091) and adjacent normal tissues (113) from The Cancer Genome Atlas (TCGA). Patients were divided into 3 equal groups by gene expression to compare high and low expressors. Tumor immune features like cytolytic activity and T cell receptor (TCR) diversity were quantified from gene expression data. Data for some of these features, mutation-related aspects, and survival were obtained from TCGA publications. Gene expression data for 55 breast cancer cell-lines was from Cancer Cell Line Encyclopedia. Cox regression and Spearman methods were used for survival and correlation analyses, resp. Welch t test was used for group comparison, with P <0.05 deemed significant. Hallmark gene-sets were used for enrichment analysis.

Results:

A3B and A3C represented 91% of A3 gene expression in breast cancer cell-lines. In patients, expression of A3B was higher in tumors compared to normal tissue (4.5x), while that of A3C was lower (0.5x). A3B or A3A levels had no effect on overall (OS) or disease-specific survival (DSS). But, higher expression for each of A3C-H was significantly associated with improved OS (HR, 0.45-0.66) or DSS (0.43-0.61). The prognostic value of high A3C-H expression was validated in two gene expression meta-datasets (KMPlot and SurvExpress). A3A and A3B expression levels correlated with both tumor mutation burden and neoantigen load (ρ = 0.28-0.34), which resp. were 2.0-2.9x more in high expressors. There was no association of tumor mutation burden or neoantigen load with A3C-H. A3C-H expression levels correlated positively with both total immune cell and lymphocyte populations in tumor (ρ = 0.29-0.70 & 0.20-0.50, resp.), whereas the correlations were poor for A3B (0.10 & -0.01, resp.). Expression of genes related to immune function like interferon response and complement activation was enriched in high A3C-H expressors, which also had significantly more CD4 and CD8 T cells, and TCR diversity (2.3-4.0x, 2.1-5.4x & 1.3-2.1x, resp.). Concordantly, for each of A3C-H, expression correlated with tumor immune cytolytic activity (ρ = 0.31-0.79), which was increased 3.1-7.9x in high expressors.

Conclusion:

APOBEC3s are DNA mutators. However, unlike A3B, whose expression is associated with poor survival, increased expression of A3C-H confers a survival benefit. Further studies are warranted to explore if the increased A3C-H expression reflects a heightened anti-cancer immune response, and if A3C-H can be used as prognostic biomarkers.

20.14 The Readability of Surgical Consent Forms is Poor Across Three Countries

Posted on January 31, 2019

A. Chakrabarty1, E. Kaplan1, L. Wood1, I. Marques1, K. Kichler1, S. J. Baker1, J. W. Toh3, E. M. Muller2, G. D. Kennedy1, M. S. Morris1, J. S. Richman1, D. I. Chu1  1University Of Alabama at Birmingham,Birmingham, Alabama, USA 2University of Cape Town,General Surgery,Cape Town, WESTERN CAPE, South Africa 3University Of Sydney,Sydney, NSW, Australia

Introduction:
The American Medical Association (AMA) and the National Institutes of Health (NIH) recommend that education materials given to patients should not exceed a sixth-grade reading level. Consent forms are legal documents that patients are expected to read, understand and sign before any surgical procedure. It is unclear, however, how readable contemporary consent forms are and whether these levels vary internationally. We hypothesized that the readability of consent forms would be poor and exceed the recommended sixth grade reading level.

Methods:
Major surgery English-consent forms were collected from four tertiary-care referral-centers across three countries: USA, Australia, and South Africa. Consent forms were analyzed to assess readability using four instruments: Flesch-Kincaid Grade Level (FKGL) instrument, SMOG (Simple Measure of Gobbledygook), PEMAT (Patient Education Materials Assessment Tool), and PCR (Print Communication Rating). Three independent observers analyzed each form to assess readability. 

Results:
Seven consent forms were analyzed from three countries.  None of the materials were under sixth-grade reading level when analyzed with FKGL and SMOG with average grade-level scores of 12.0 ± 2.4 SD and 15.2 ± 2.0 SD, respectively. The range for FKGL was 9 to 15 while the range for SMOG was 13.5 to 17 where the higher scores indicate a higher reading level. While no significant differences existed between FKGL and SMOG scores by institutions, Australia had the best FKGL and SMOG scores, at 9 and 13.5 respectively. The average PEMAT scores were 70.8% ± 13.8 SD for understandability and 30.5% ± 25.8 SD for actionability, with scores closer to 100% being ideal. No significant differences in PEMAT scores were observed by institutions, but Australia had the highest PEMAT scores for both understandability and actionability, at 85.2% and 40%, respectively. The average PCR score was 40.1 ± 4.6 SD and all consent forms scored in the 24-47 score range, for which “augmented efforts to eliminate literacy-related barriers” are recommended. While no significant differences in PCR scores were observed by institution, Australia again had the highest score, at 43 ± 5.2 SD.

Conclusion:
The readability of major surgery consent forms from three countries varied but was overall poor and failed to meet the AMA/NIH recommended sixth-grade reading level. While consent forms are legal documents, considerations should be made to make consent forms more readable and understandable.
 

20.13 What Does the Average Person Know about Endocrine and Vascular Surgeons?

Posted on January 31, 2019

A. Aune1, A. Asban1, R. Mallick1, H. Chen1, B. Lindeman1  1University Of Alabama at Birmingham,Department Of Surgery,Birmingham, Alabama, USA

Introduction:
Surgical fields are becoming increasingly specialized. This can lead to misunderstanding or confusion about the scope of practice of different surgeons by the individual seeking specialized surgical care. To assess public understanding of sub-specialty surgeons, we sought to survey general knowledge of the specialty areas of Endocrine Surgery and Vascular Surgery. 

Methods:
A survey was conducted in three locations in Birmingham, Alabama: a local farmers market, a public park, and the University of Alabama at Birmingham Hospital (UAB). Fifty people were surveyed at random at each of the three locations, with hospital staff identified by wearing a hospital ID badges recruited at the UAB hospital location. Participants were asked to define both an endocrine surgeon and vascular surgeon, as well as identify aspects of their practice. Participant’s answers to the survey were recorded and coded by three evaluators (two MD, one PharmD candidate). Survey responses were assessed for correct definition of the specialty (Yes/No), recognition of being a surgeon (Yes/No), spectrum of practice (None, Partial or Complete), and presence of a common misconception (Yes/No). Inter-rater reliability (kappa) was calculated for each question. The Chi-square test was used to compare the difference in each answer between the two specialties. 

Results:
A total of 150 people participated in the study. The majority were female (58%) and approximately 50 years of age or less (65%). Inter-rater reliability from 0.32-0.84 was observed, and agreement from 40% to 98% between raters was achieved for all questions. Significantly more respondents recognized endocrine surgery as a surgical profession (21%) compared to vascular surgeons (18%) (p<0.001). However, significantly fewer could define what an endocrine surgeon does (14%) than could define what a vascular surgeon does (57%). Only 3% of respondents could identify the entire spectrum of practice of an endocrine surgeon, with 42% and 55% providing partially or completely incorrect responses, respectively. Significantly more respondents could identify all of a vascular surgeon’s spectrum of practice (11%), with 60% and 29% providing partial or completely incorrect responses, respectively (p<0.001). Endocrine surgeons were most often confused for endocrinologists (40%), while vascular surgeons were most often confused for cardiovascular surgeons (22%).  

Conclusion:
This study reveals an overall lack of understanding among the general public about what endocrine and vascular surgeons are and their spectrum of practice and shows that public understanding of the field of endocrine surgery is very low. More efforts need to be made to increase the visibility of these fields and communicate these surgeons’ specialized expertise. 

20.12 Improving Patient Education Material is Feasible at the VA

Posted on January 31, 2019

C. M. Rentas1, S. Baker1, E. Malone1, J. Richman1, G. Yang1, M. Morris1  1University Of Alabama at Birmingham,Birmingham, Alabama, USA

Introduction: Health literacy is a predictor of a patient’s health status. Despite variability of patient health literacy, patient education handouts remain the most widely used form of medical information. The American Medical Association (AMA) and National Institutes of Health (NIH) recommend that patient information be presented at 6th grade reading level or lower. Not only do patient education handouts need to be readable, the medical information presented should also be understandable to the general public. We hypothesized that patient education handouts at our local Veterans Affairs Medical Center general surgery clinic were written above a 6th grade reading level and contained information that was not understandable to the average patient.

Methods: Routine patient education materials were collected from the general surgery clinic. The Flesch-Kincaid Grade Level (FKGL) instrument was used to analyze the texts to generate a FKGL score without any correction of misspellings or grammatical errors. To assess understandability, we used the Patient Education Materials Assessment Tool (PEMAT) and recorded scores of “understandability” and “actionability” for each patient education handout. Then, patient education handouts were re-written using recommendations from the Centers for Disease Control and Prevention’s “Simply Put” guide for creating easy-to-understand materials and re-assessed using the FKGL and PEMAT tools.

Results: We collected 5 patient education handouts from the general surgery clinic covering various topics such as: colectomy, hernia repair, cholecystectomy. The overall average FKGL for the handouts was 7.94 (SD 0.49), exceeding the NIH/AMA standards sixth grade level by an average of 1.94 grade levels (95% CI=7.33-8.55; p <0.0002). The overall average PEMAT scores for both understandabilty and actionability were 40% (SD 6%). Handouts were then rewritten. The average time to rewrite a handout was 1 hour. Upon re-assessment the average FKGL for the rewritten handouts was 5.4 (SD 0.35, 95% CI=4.97-5.83) % below the grade level. The average PEMAT understandability and actionability scores for the rewritten material are 100% and 82%, respectively (SD 0, 2%), compared to 40% for both before.

Conclusion: The readability of patient education material in our VA general surgery clinic is poor and deviates significantly from AMA/NIH recommendations. With limited time and resources, the FKGL and PEMAT scores for the patient education handouts were improved using the “Simply Put” guidelines to ensure readability and understandability of medical information.

 

20.11 Medical Student Perceptions Following Participation in a Surgical Boot Camp – A Qualitative Analysis

Posted on January 31, 2019

E. Palmquist1, T. Feeney2, A. Chatterjee1, D. Nepomnayshy3, L. Chen1  1Tufts Medical Center,Department Of Surgery,Boston, MA, USA 2Boston University,Department Of Surgery,Boston, MA, USA 3Lahey Hospital & Medical Center,Department Of Surgery,Burlington, MA, USA

Introduction: There have been many changes to surgical education over the last few decades. With increased attention to patient safety, there is a push to better prepare our medical students prior to starting a surgical residency. We present our results from a pilot study of creating a senior medical student surgical boot camp including analysis of the learner’s perspectives of boot camps.

Methods: Graduating senior medical students entering a surgical residency underwent a voluntary three-day surgical boot camp. Pre-and post-surveys were used to evaluate confidence levels of common patient management issues as well as technical skills. Qualitative analysis of a focus group using a general inductive approach was used to develop themes surrounding students’ perceptions of boot camps.
 

 

Results: Ten medical students completed the boot camp. We found that most students were somewhat confident (3 on a 5-point Likert scale) in their abilities to manage common intern problems with increased variation among students for technical skills prior to the boot camp. Students all had improvements in confidence scores post boot camp for all measured tasks.

From our qualitative analysis we found that students prefer a voluntary, surgery specific boot camp at the end of medical school as oppose to the start of their residency. Being given the choice to partake in the intervention provided the participating students with more motivation during the boot camp, supporting adult learning theory. Some of the students’ major concerns include being the first point of contact for patient issues as well as being the first responder to patient emergencies. Students worry about their ability to multi-task and manage a large amount of information which differed from their experience as a medical student. In addition, students are realistic about their expectations from a preparatory boot camp and value it as an experience to help “jump start” their transition to residency.

 

Conclusion: Our pilot study suggests that surgical boot camps may successfully improve students’ confidence in patient management and technical skills prior to the start of their intern year. In addition, we found major themes surrounding students’ perceptions of boot camp which may assist with future development of these programs. Students prefer a voluntary boot camp and value the experience at a medical school level. In addition, they are realistic in that a preparatory course will not teach them all they need to know prior to residency but more as a tool to help their transition.  
 

20.07 Acquisition of Surgical Skills by Medical Students in State-Owned Medical Schools of Cameroon.

Posted on January 31, 2019

A. Chichom-Mefire1, G. N. Keith1, P. Fokam1, D. S. Nsagha1, M. Ngowe-Ngowe1  1Faculty of Health Sciences, University of Buea,Department Of Surgery,Buea, Cameroon

Introduction: Surgery plays an important role in provision and support of primary health care services. The World Health Organization recommends that basic surgical care be administered at the district level. Due to limited availability of qualified surgeons, general practitioners need to be competent in a number of practical surgical skills in order to reduce the number of referrals for emergency and selected elective surgical procedures. Curriculum of medical schools in low and middle-income countries must be designed accordingly. The aim of this study was to report the level of exposure of final year medical students to practical surgical skills.

Methods:

A descriptive cross-sectional study was carried out in the four state owned medical schools in Cameroon. The target population was final year medical students who have completed all clinical rotations. All final year medical students were approached.

A structured self-administered questionnaire was proposed to these students in order to assess their exposure to basic surgical skills and selected surgical procedures. Self-confidence in performing basic surgical skills (BSS) was assessed using a Likert scale. Adequate exposure for a given surgical procedure was defined as at least one of the following: (1) observing the procedure five or more times and participating as fist assistant at least four times and performing it at least once under supervision. (2) Observing the procedure five times and participating as first assistant at least five times. Data analysis was performed using EPI INFO version 7.2 and statistical significance was set at P < 0.05.

Results:
Of the 347 final year medical students approached, 304 returned filled questionnaires giving a response rate of 87.6%. Male to female ratio was 5:4 and females were significantly younger than males (P < 0.001). Their comfort in basic surgical skills ranged from 25% (manual surgical node tying) to 86% (surgical scrubbing). Adequate exposure to selected surgical procedures was 87% for perineal tear repair after vaginal delivery, 81% for caesarean section and incision and drainage of an abscess, 73% for cast immobilisation of a limb fracture, 55% for hernia repair and 53% for appendectomy. It was as low as 3% for bowel resection and anastomosis. The choice to perform extra-curricular activity for skills improvement was significantly associated with adequate exposure (P < 0.05).

Conclusion:
Overall, the performance rate of practical surgical skills by final year medical students in medical schools in Cameroon is poor. However, the majority of students are likely to be able to perform a sizeable number of surgical procedures by the end of their training. There is need to reinforce the training and assessment to ensure that medical students who do not master basic clinical skills and are not adequately exposed to common procedures are given an opportunity to be exposed before graduation.

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