Behind the pattern: General surgery residsent autonomy in robotic surgery.

Objective: Robotic surgery is increasingly utilized and common in general surgery training programs. This study sought to better understand the factors that influence resident operative autonomy in robotic surgery. We hypothesized that resident seniority, surgeon work experience, surgeon robotic-assisted surgery (RAS) case volume, and procedure type influence general surgery residents' opportunities for autonomy in RAS as measured by percentage of resident individual console time (ICT). Methods: General surgery resident ICT data for robotic cholecystectomy (RC), inguinal hernia (RIH), and ventral hernia (RVH) operations performed on the dual-console Da Vinci surgical robotic system between July 2019 and June 2021 were extracted. Cases with postgraduate year (PGY) 2-5 residents participating as a console surgeon were included. A sequential explanatory mixed-methods approach was undertaken to explore the ICT results and we conducted secondary qualitative interviews with surgeons. Descriptive statistics and thematic analysis were applied. Results: Resident ICT data from 420 robotic cases (IH 200, RC 121, and VH 99) performed by 20 junior residents (PGY2-3), 18 senior residents (PGY4-5), and 9 attending surgeons were extracted. The average ICT per case was 26.8 % for junior residents and 42.4 % for senior residents. Compared to early-career surgeons, surgeons with over 10 years' work experience gave less ICT to junior (18.2 % vs. 32.0 %) and senior residents (33.9 % vs. 56.6 %) respectively. Surgeons' RAS case volume had no correlation with resident ICT (r = 0.003, p = 0.0003). On average, residents had the most ICT in RC (45.8 %), followed by RIH (36.7 %) and RVH (28.6 %). Interviews with surgeons revealed two potential reasons for these resident ICT patterns: 1) Surgeon assessment of resident training year/experience influenced decisions to grant ICT; 2) Surgeons' perceived operative time pressure inversely affected resident ICT. Conclusions: This study suggests resident ICT/autonomy in RC, RIH, and RVH are influenced by resident seniority level, surgeon work experience, and procedure type, but not related to surgeon RAS case volume. Design and implementation of an effective robotic training program must consider the external pressures at conflict with increased resident operative autonomy and seek to mitigate them.

Clinical characteristics and outcomes of adrenal hemorrhage.

BACKGROUND: Although uncommon, adrenal hemorrhage has multiple etiologies. Because clinical characteristics, management, and outcomes of patients with adrenal hemorrhage are inadequately described, we examined the underlying etiology, need for intervention, evolution of imaging characteristics, and adequacy of subsequent evaluation. METHODS: We performed a retrospective review of patients diagnosed with adrenal hemorrhage (radiologist-confirmed density consistent with hemorrhage on computed tomography) from 2005 to 2021 at a university-based institution. Demographic characteristics, hemorrhage etiology, and subsequent follow-up were analyzed. RESULTS: Of 193 adrenal hemorrhage patients, the mean age was 49.2 ± 18.3 years, and 35% were female. Clinical presentations included trauma (47%), abdominal or flank pain (28%), incidental findings on imaging acquired for other reasons (12%), postoperative complication (8%), or shock (3%). Hemorrhage outside of the gland was present in 62% of patients. Unilateral hemorrhage was more frequent (93%) than bilateral (7%). A total of 12% of patients had nodules, but only 70% of these were identified on initial imaging, and only 43% had hormonal evaluation. Of 7 patients who had adrenalectomy or biopsy, pathology was either benign (57%) or nonadrenal malignancy (43%). No adrenocortical carcinomas were identified. Follow-up imaging was performed in 56% of patients and revealed decreased, stable, resolved, or increased adrenal hemorrhage size in 39%, 19%, 30%, and 12% of patients, respectively. CONCLUSION: Adrenal hemorrhage is secondary to multiple etiologies, most commonly trauma. In the setting of adrenal hemorrhage, many adrenal nodules were not identified on initial imaging. Only a minority of patients with nodules underwent "complete" biochemical evaluation. Follow-up imaging may improve the identification of underlying nodules needing hormonal evaluation.

Endoscopic impedance planimetry versus high-resolution manometry (HRM) for pre-operative motility evaluation in anti-reflux surgery.

INTRODUCTION: Pre-operative evaluation of patients with gastroesophageal reflux disease (GERD) includes assessment of esophageal motility. High-resolution manometry (HRM) is the gold standard; endoscopic impedance planimetry (IP) with Endoflip 2.0 is increasingly utilized in esophageal disorders of motility. We hypothesized that normal IP motility would correlate with normal HRM motility and tested this in a prospective cohort study. METHODS: Patients presenting for surgical evaluation of GERD between 9/2020 and 10/2021 were prospectively enrolled under an IRB-approved protocol. Patients with prior esophageal/gastric surgery, known motility disorders, or large paraesophageal hernias were excluded. All underwent HRM and IP, with normal motility defined by Chicago 3.0 classification for HRM and the presence of repetitive antegrade contractions for IP. Logistic regression and t test were used to analyze the data; p value < 0.05 was considered significant. RESULTS: Of 63 patients enrolled, 48 completed both IP and HRM testing. The cohort was 50% male with a median age of 52.5 [42.0, 66.0] years, mostly ASA class 1-2 (75.1%, n = 36) and had an average BMI of 31.4 ± 6.3 kg/m2. Normal motility tracings were in 62.5% of IP and 75% of HRM tests. Using HRM as the gold standard, IP detected normal motility with a sensitivity of 65.8% and a specificity of 50% (positive predictive value 83.3%, negative predictive value 27.8%). Normal IP was not statistically significant in predicting normal HRM (OR 3.182, 95% CI 0.826-12.262, p = 0.0926). Tolerability of IP was significantly better than HRM with lower rates of discomfort (10.9% vs. 93.4%, p < 0.0001) and higher willingness to repeat testing (100% vs. 47.8%, p < 0.0001). CONCLUSION: Esophageal motility testing with Endoflip 2.0 is well tolerated by patients. The low specificity (50%), poor negative predictive value (27.8%), and lack of statistically significant concordance between IP and HRM raises concern for the reliability of this test as a stand-alone replacement for HRM in the pre-operative evaluation for GERD.

The impact of procedural activities on musculoskeletal pain experienced by pregnant surgeons.

BACKGROUND: Two-thirds of surgeons report work-related musculoskeletal disorders (WRMD). There is limited data on WRMD symptoms experienced by pregnant surgeons. METHODS: We distributed an electronic survey via personal contacts to attending and trainee surgeons across six academic institutions to assess the impact of procedural activities and surgical ergonomics (SE) on WRMD symptoms during pregnancy. RESULTS: Fifty-three respondents were currently or had been pregnant while clinically active, representing 93 total pregnancies. 94.7% reported that symptoms were exacerbated by workplace activities during pregnancy and 13.2% took unplanned time off work as a result. Beyond 24 weeks of pregnancy, 89.2% of respondents continued to operate/perform procedures, 81.7% worked >24-h shifts and 69.9% performed repetitive lifting >50 pounds. No respondents were aware of any institutional pregnancy-specific SE policies. CONCLUSIONS: Procedural activities can exacerbate pain symptoms for the pregnant surgeon. SE best practices during pregnancy warrant further attention.

Optimal Timing of Fundamentals of Endoscopic Surgery (FES) Testing in General Surgery Residency: Early Is Better.

BACKGROUND: Fundamentals of endoscopic surgery (FES) completion is mandatory for certification by the American Board of Surgery (ABS). As early simulation and competency assessment can bolster development of trainee proficiency, we sought to determine the optimal timing for FES examination by evaluating pass rates based on training level and previous endoscopic experience. METHODS: PGY2-5 residents at a university-based medical center who were novice to FES were assigned to complete FES training and testing. Training year, prior endoscopic experience, and FES exam scores were recorded with pre- and post-test surveys. RESULTS: Most residents in the program (88%) were able to complete FES training and testing within a single academic year. Most required only a single faculty-led session (88%) to feel confident to take the exam, augmented by varying numbers of independent practice sessions (50% 1-2, 19% 3-5, 27% > 5). After training, most (84%) felt confident that they would pass the exam, and 93% did so on their first attempt. While higher written exam scores were noted in the PGY5 group, there were no other statistically significant differences in overall pass rates or technical exam scores based on PGY level (p = 0.24). A number of previously completed endoscopic cases did not correlate with exam scores (p = 0.24 written, p = 0.91 technical). CONCLUSION: Fundamentals of endoscopic surgery (FES) certification can be successfully completed by junior level general surgery residents regardless of previous endoscopic experience. Moving this exam to earlier training years can benefit resident development and preparedness in the clinical setting without negatively impacting pass rates.

The effect of frailty and age on outcomes in elective paraesophageal hernia repair.

INTRODUCTION: Paraesophageal hernia repair (PEHR) is a safe and effective operation. Previous studies have described risk factors for poor peri-operative outcomes such as emergent operations or advanced patient age, and pre-operative frailty is a known risk factor in other major surgery. The goal of this retrospective cohort study was to determine if markers of frailty were predictive of poor peri-operative outcomes in elective paraesophageal hernia repair. METHODS: Patients who underwent elective PEHR between 1/2011 and 6/2022 at a single university-based institution were identified. Patient demographics, modified frailty index (mFI), and post-operative outcomes were recorded. A composite peri-operative morbidity outcome indicating the incidence of any of the following: prolonged length of stay (≥ 3 days), increased discharge level of care, and 30-day complications or readmissions was utilized for statistical analysis. Descriptive statistics and logistic regression were used to analyze the data. RESULTS: Of 547 patients who underwent elective PEHR, the mean age was 66.0 ± 12.3, and 77.1% (n = 422) were female. Median length of stay was 1 [IQR 1, 2]. ASA was 3-4 in 65.8% (n = 360) of patients. The composite outcome occurred in 32.4% (n = 177) of patients. On multivariate analysis, increasing age (OR 1.021, p = 0.02), high frailty (OR 2.02, p < 0.01), ASA 3-4 (OR 1.544, p = 0.05), and redo-PEHR (OR 1.72, p = 0.02) were each independently associated with the incidence of the composite outcome. On a regression of age for the composite outcome, a cutoff point of increased risk is identified at age 72 years old (OR 2.25, p < 0.01). CONCLUSION: High frailty and age over 72 years old each independently confer double the odds of a composite morbidity outcome that includes prolonged post-operative stay, peri-operative complications, the need for a higher level of care after elective paraesophageal hernia repair, and 30-day readmission. This provides additional information to counsel patients pre-operatively, as well as a potential opportunity for targeted pre-habilitation.

Early postoperative telehealth visit protocol implementation reduces emergency department utilization following benign foregut procedures.

INTRODUCTION: Emergency department (ED) visits and readmissions following benign foregut surgery (BFS) represent a burden on patients and the health care system. The objective of this study was to identify differences in ED visits and readmissions before and after implementation of an early postoperative telehealth visit protocol for BFS. We hypothesized that utilization of telehealth visits would be associated with reduced post-operative ED and hospital utilization. METHODS: An early postoperative telehealth protocol was initiated in 2020 at an academic medical center to provide a video conference within the first postoperative week. Consecutive elective BFS including fundoplication, Linx, paraesophageal hernia repair, and Heller myotomy performed between 2018 and 2022 were included. Outcomes included ED visits and 30-day readmission. Bivariate analyses were performed using Chi-squared testing for categorical variables. The association between telehealth visits and outcomes were evaluated using multivariable logistic regression. RESULTS: 616 patients underwent BFS during the study period. 310 (50.3%) were performed prior to the implementation of telehealth visits and 306 (49.7%) were after. 241 patients in the telehealth visit group (78.8%) completed their telehealth visit. A total of 34 patients (5.5%) had ED visits without readmission while 38 patients (6.2%) were readmitted within the first 30 days. The most common cause of ED visits and readmissions included pain (n = 18, 25%) and nausea/vomiting (n = 12, 16%). There was a significant reduction in ED visits without admission following telehealth visit implementation (7.4% vs 3.6%; OR 2.20, 95% CI 1.04-4.65, p = 0.04). There was no difference in readmission rates (6.1% versus 6.5%; OR 0.89, 95% CI 0.46-1.73, p = 0.73). The telehealth cohort had significantly lower ED visits for pain (31% vs 16.7%, p = 0.04) and nausea/vomiting (23.8% vs 6.7%, p = 0.02). DISCUSSION: Early telehealth follow-up was associated with a significant decrease in ED visits following BFS. The majority of this was attributable to a reduction in ED visits for pain, nausea, and vomiting. These results provide a possible avenue for improving quality and cost-effectiveness within this patient population.

Assessing the effects of smoking status on outcomes of elective minimally invasive paraesophageal hernia repair.

BACKGROUND: Patients are often advised on smoking cessation prior to elective surgical interventions, but the impact of active smoking on paraesophageal hernia repair (PEHR) outcomes is unclear. The objective of this cohort study was to evaluate the impact of active smoking on short-term outcomes following PEHR. METHODS: Patients who underwent elective PEHR at an academic institution between 2011 and 2022 were retrospectively reviewed. The National Surgical Quality Improvement Program (NSQIP) database from 2010 to 2021 was queried for PEHR. Patient demographics, comorbidities, and 30-day post-operative data were collected and maintained in an IRB-approved database. Cohorts were stratified by active smoking status. Primary outcomes included rates of death or serious morbidity (DSM) and radiographically identified recurrence. Bivariate and multivariable regressions were performed, and p value < 0.05 was considered statistically significant. RESULTS: 538 patients underwent elective PEHR in the single-institution cohort, of whom 5.8% (n = 31) were smokers. 77.7% (n = 394) were female, median age was 67 [IQR 59, 74] years, and median follow-up was 25.3 [IQR 3.2, 53.6] months. Rates of DSM (non-smoker 4.5% vs smoker 6.5%, p = 0.62) and hernia recurrence (33.3% vs 48.4%, p = 0.09) did not differ significantly. On multivariable analysis, smoking status was not associated with any outcome (p > 0.2). On NSQIP analysis, 38,284 PEHRs were identified, of whom 8.6% (n = 3584) were smokers. Increased DSM was observed among smokers (non-smoker 5.1%, smoker 6.2%, p = 0.004). Smoking status was independently associated with increased risk of DSM (OR 1.36, p < 0.001), respiratory complications (OR 1.94, p < 0.001), 30-day readmission (OR 1.21, p = 0.01), and discharge to higher level of care (OR 1.59, p = 0.01). No difference was seen in 30-day mortality or wound complications. CONCLUSION: Smoking status confers a small increased risk of short-term morbidity following elective PEHR without increased risk of mortality or hernia recurrence. While smoking cessation should be encouraged for all active smokers, minimally invasive PEHR in symptomatic patients should not be delayed on account of patient smoking status.

What influences general surgery residents' prospective entrustment and operative time in robotic inguinal hernia repairs.

INTRODUCTION: Teaching residents robotic-assisted inguinal hernia repair (RIHR) is an increasingly common extension of contemporary surgical training. This study sought to investigate what variables would influence operative time (OT) and resident prospective entrustment in RIHR cases. METHODS: We prospectively collected 68 resident RIHR operative performance evaluations with a validated instrument. Outpatient RIHR cases performed by 11 general surgery residents during 2020-2022 were included. The overall OT of matched cases was extracted from hospital billing; matched procedural step-specific OT was obtained from Intuitive Data Recorder (IDR). Statistical analysis was performed using Pearson correlation and one-way ANOVA. RESULTS: The evaluation instrument reliably assessed residents' RIHR performance (Cronbach's α = 0.93); residents' prospective entrustment strongly correlated with overall guidance provided by attending surgeon (r = 0.86, p < 0.0001) and operative plan and judgment (r = 0.85, p < 0.0001). The overall OT was significantly associated with resident's team management (r = - 0.35, p = 0.011). Procedural step-specific OT was significantly associated with residents' step-specific skill (r = - 0.32, p = 0.014). On average, RIHR cases with the highest level of prospective entrustment (Resident can teach junior) showed the shortest step-specific OT. Entrustment level 3 (Reactive guidance needed) was the turning point of all four RIHR procedural step-specific OT. CONCLUSIONS: Our findings suggest that in RIHR, attending guidance, resident operative plan and judgment, and resident technical skill contribute to resident prospective entrustment; resident team management, technical skill, and attending guidance influence operative time, which in turn impacts attendings' determination of resident prospective entrustment. Future studies with a larger sample size are needed to further validate the findings.

Is Robotic Console Time a Surrogate for Resident Operative Autonomy?

OBJECTIVE: Robotic-assisted surgery is an increasing part of general surgery training, but resident autonomy on the robotic platform can be hard to quantify. Robotic console time (RCT), the percentage of time the resident controls the console, may be an appropriate measure of resident operative autonomy. This study aims to characterize the correlation between objective resident RCT and subjectively scored operative autonomy. METHODS: Using a validated resident performance evaluation instrument, we collected resident operative autonomy ratings from residents and attendings performing robotic cholecystectomy (RC) and robotic inguinal hernia repair (IH) at a university-based general surgery program between 9/2020-6/2021. We then extracted RCT data from the Intuitive surgical system. Descriptive statistics, t-tests and ANOVA were performed. RESULTS: A total of 31 robotic operations (13 RC, 18 IH) performed by 4 attending surgeons and 8 residents (4 junior, 4 senior) were matched and included. 83.9% of cases were scored by both attending and resident. The average RCT per case was 35.6%(95% CI 13.0%,58.3%) for junior residents (PGY 2-3) and 59.7%(CI 51.1%,68.3%) for senior residents (PGY 4-5). The mean autonomy evaluated by residents was 3.29(CI 2.85,3.73) out of a maximum score of 5, while the mean autonomy evaluated by attendings was 4.12(CI 3.68,4.55). RCT significantly correlated with subjective evaluations of resident autonomy (r=0.61, p=0.0003). RCT also moderately correlated with resident training level (r=0.5306, p<0.0001). Neither attending robotic experience nor operation type significantly correlated with RCT or autonomy evaluation scores. CONCLUSIONS: Our study suggests that resident console time is a valid surrogate for resident operative autonomy in robotic cholecystectomy and inguinal hernia repair. RCT may be a valuable measure in objective assessment of residents' operative autonomy and training efficiency. Future investigation into how RCT correlates with subjective and objective autonomy metrics such as verbal guidance or distinguishing critical operative steps is needed to validate the study findings further.

Distortions in the Balance Between Teaching and Efficiency in the Operating Room.

INTRODUCTION: The balance between teaching and operative efficiency (i.e., continuing operative case progression) is difficult for even the most experienced master surgeon educators. The purpose of this study was to explore influencing factors behind attending surgeons' decisions to break the balance between operative efficiency and teaching in the operating room. METHODS: Semistructured interviews were conducted with surgeons across the United States via Web-based video conferencing. The interviews were audio-recorded and transcribed. Qualitative analysis using the framework method was utilized, and emergent themes were identified. RESULTS: Twenty-three attending surgeons from 8 academic institutions and 11 surgical specialties completed interviews (14 men and 9 women). Attending surgeons consider a variety of factors associated with their dual roles (surgeon versus teacher) when balancing operative efficiency and providing appropriate independence for residents with oversight to promote autonomy. These were divided into surgeon-role-related factors (patient safety, financial factors, scheduling factors, preservation of faculty reputation for efficiency, and mode of operation) as well as teacher-role-related factors (preparation, level, and technical skill of the resident). These factors then informed attending surgeons' determinations about how the case was progressing, which prompted them to intervene and reduce resident autonomy or allow the resident to continue. CONCLUSIONS: Surgeons consider numerous factors when deciding how to balance resident teaching and autonomy while preserving operative efficiency. These findings provide helpful insights for surgical departments to consider inclusion in faculty-development programs, resident education, and systematic improvements.

Somatic inactivation of breast cancer predisposition genes in tumors associated with pathogenic germline variants.

BACKGROUND: Breast cancers (BCs) that arise in individuals heterozygous for a germline pathogenic variant in a susceptibility gene, such as BRCA1 and BRCA2, PALB2, and RAD51C, have been shown to exhibit biallelic loss in the respective genes and be associated with triple-negative breast cancer (TNBC) and distinctive somatic mutational signatures. Tumor sequencing thus presents an orthogonal approach to assess the role of candidate genes in BC development. METHODS: Exome sequencing was performed on paired normal-breast tumor DNA from 124 carriers of germline loss-of-function (LoF) or missense variant carriers in 15 known and candidate BC predisposition genes identified in the BEACCON case-control study. Biallelic inactivation and association with tumor genome features including mutational signatures and homologous recombination deficiency (HRD) score were investigated. RESULTS: BARD1-carrying TNBC (4 of 5) displayed biallelic loss and associated high HRD scores and mutational signature 3, as did a RAD51D-carrying TNBC and ovarian cancer. Biallelic loss was less frequent in BRIP1 BCs (4 of 13) and had low HRD scores. In contrast to other established BC genes, BCs from carriers of CHEK2 LoF (6 of 17) or missense (2 of 20) variant had low rates of biallelic loss. Exploratory analysis of BC from carriers of LoF variants in candidate genes such as BLM, FANCM, PARP2, and RAD50 found little evidence of biallelic inactivation. CONCLUSIONS: BARD1 and RAD51D behave as classic BRCA-like predisposition genes with biallelic inactivation, but this was not observed for any of the candidate genes. However, as demonstrated for CHEK2, the absence of biallelic inactivation does not provide definitive evidence against the gene's involvement in BC predisposition.

Repeat Laparoscopic Cholecystectomy for Duplicated Gallbladder After 16-Year Interval.

Background: Gallbladder duplication can present a diagnostic challenge, particularly in patients who have had prior cholecystectomy with a missed duplicated gallbladder. Case Presentation: Presented is the case of a man with 16 years of recurrent, persistent right upper quadrant pain after cholecystectomy who was found to have a duplicated gallbladder. Conclusions: Gallbladder duplication can be difficult to diagnose and frequently evades preoperative visualization. In particular, patients who have had prior operations or infections that may lead to epigastric adhesions are at higher risk for a missed gallbladder duplication at time of operation. An intraoperative cholangiogram should be routinely performed when the inferior liver margin is poorly visualized due to scarring or patient habitus. Gallbladder anomalies should be considered in the differential preoperatively for all patients undergoing hepatobiliary procedures and for postoperative patients with persistent biliary symptoms.

Milk-Derived Proteins and Peptides in Head and Neck Carcinoma Treatment.

Research investigating milk-derived proteins has brought to light the potential for their use as novel anticancer agents. This paper aims to systematically review studies examining the effectiveness of milk-derived proteins in the treatment of head and neck cancer. A systematic literature search of Medline, Evidence-Based Medicine, and Web of Science databases including papers published from all dates was completed. Inter-rater reliability was high during the title, abstract, and full-text screening phases. Inclusion criteria, exclusion criteria, and data extraction were based on the PICOS tool and research questions. Reporting followed the Preferred Reporting Items for Systematic Review and Meta-Analysis criteria. Eligible in vitro and in vivo studies (n = 8/658) evaluated lactoferrin, α-lactalbumin, and its complexes, such as HAMLET, BAMLET and lactalbumin-oleic acid complexes, as well as lactoperoxidase, whey, and casein. Their effectiveness in the treatment of head and neck cancer cells lines found that these compounds can inhibit tumour growth modulate cancer gene expression, and have cytotoxic effects on cancer cells. However, the exact mechanisms by which these effects are achieved are not well understood. Systematically designed, large, optimally controlled, collaborative studies, both in vitro and in vivo, will be required to gain a better understanding of their potential role in the treatment of head and neck cancer.

Predictors of mortality, limb loss, and discharge disposition at admission among patients with necrotizing skin and soft tissue infections.

BACKGROUND: Necrotizing soft tissue infections (NSTI) represent a heterogeneous group of rapidly progressive skin and soft tissue infections associated with significant morbidity and mortality. Efforts to identify factors associated with death have produced mixed results, and little or no data is available for other adverse outcomes. We sought to determine whether admission variables were associated with mortality, limb loss, and discharge disposition in patients with NSTI. METHODS: We analyzed prospectively collected data of adult patients with surgically confirmed NSTI from an NSTI registry maintained at a quaternary referral center. Factors independently associated with mortality, amputation, and skilled nursing facility discharge were identified using logistic regression. RESULTS: Between 2015 and 2018, 446 patients were identified. The median age was 55 years (interquartile range, 43-62). The majority of patients were male (65%), white (77%), and transferred from another facility (90%). The perineum was most commonly involved (37%), followed by the lower extremity (34%). The median number of operative debridements was 3 (interquartile range, 2-4). Overall mortality was 15%, and 21% of extremity NSTI patients required amputation. Age greater than 60 years; creatinine greater than 2 mg/dL; white blood cell count greater than 30 x 10^ /µl, platelets less than 150 × 10/µL, and clostridial involvement were independently associated with greater odds of death; perineal involvement was associated with lower odds of death. Age greater than 60 years; sex, male; nonwhite race; diabetes; chronic wound as etiology; leg involvement; transfer status; and sodium, less than 130 mEq/L were independently associated with amputation. Age greater than 60 years; sex, female; nonwhite race; perineal involvement; and amputation were associated with skilled care facility discharge. CONCLUSION: Necrotizing soft tissue infections are a heterogeneous group of infections involving significantly different patient populations with different outcomes; efforts to differentiate and predict adverse outcomes in NSTI should include laboratory data, comorbidities, infection site, and/or etiology to improve predictions and better account for this heterogeneity. LEVEL OF EVIDENCE: Prognostic, Level III.

The Role of Implant-Tooth Distance on Marginal Bone Levels and Esthetics.

PURPOSE: The peri-implant bone and mucosa architecture contribute to the health and esthetics of single-tooth dental implants. The implant-tooth distance (ITD) has been regarded as a key determinant of their outcomes. This study was conducted to determine the relationship between ITD and peri-implant bone, mucosa, and pink esthetic scores (PES) for anterior single-tooth implants. MATERIALS AND METHODS: For 44 dental implants with a microthread conical abutment interface design placed in 38 participants, periapical radiographs and photographs were evaluated at 1 and 4 years to assess interproximal bone levels and PES. RESULTS: Mean mesial and distal marginal bone level change over 4 years was 0.20 ± 1.00 mm and 0.20 ± 0.74 mm, respectively. In this cohort there was no relationship between ITD and interproximal bone changes or papilla fill at 4 years; however, marginal bone changes influenced PES score-the smaller the ITD, the lower the PES (P < .001). Alone, ITD did not influence marginal bone levels or papilla in this cohort. CONCLUSION: These results imply a complex relationship between ITD, marginal bone levels, and PES scores for single-tooth implants.

Scent matters: differential contribution of scent to insect response in flowers with insect vs. wind pollination traits.

Background and Aims: Growing experimental evidence that floral scent is a key contributor to pollinator attraction supports its investigation as a component of the suite of floral traits that result from pollinator-mediated selection. Yet, the fate of floral scent during the transition out of biotic into abiotic pollination has rarely been tested. In the case of wind pollination, this is due not only to its rarer incidence among flowering plants compared with insect pollination, but also to the scarcity of systems amenable to genus-level comparisons. Thalictrum (Ranunculaceae), with its multiple transitions from insect to wind pollination, offers a unique opportunity to test interspecific changes in floral fragrance and their potential impact on pollinator attraction. Methods: First, the Thalictrum phylogeny was revised and the ancestral character state of pollination mode was reconstructed. Then, volatile organic compounds (VOCs) that comprise the scent bouquets of flowers from 11 phylogenetically representative wind- and insect-pollinated species were characterized and compared. Finally, to test the hypothesis that scent from insect-pollinated flowers elicits a significantly greater response from potential pollinators than that from wind-pollinated flowers, electroantennograms (EAGs) were performed on Bombus impatiens using whole flower extracts. Key Results: Phylogenetic reconstruction of the pollination mode recovered 8-10 transitions to wind pollination from an ancestral insect pollination state and two reversals to insect pollination. Biochemical and multivariate analysis showed that compounds are distinct by species and only partially segregate with pollination mode, with no significant phylogenetic signal on scent composition. Floral VOCs from insect-pollinated Thalictrum elicited a larger antennal response from potential insect pollinators than those from wind-pollinated congeners. Conclusions: An evolutionary scenario is proposed where an ancestral ability of floral fragrance to elicit an insect response through the presence of specific compounds was independently lost during the multiple evolutionary transitions to wind pollination in Thalictrum.

Characterization of the meningococcal serogroup X capsule N-acetylglucosamine-1-phosphotransferase.

Neisseria meningitidis serogroups A, B, C, Y, W135 and X are responsible for most cases of meningococcal meningitis. Neisseria meningitidis serogroup X has recently emerged as a contributor to outbreaks of disease in Africa, but there is currently no vaccine against serogroup X. Understanding of the biosynthesis of the serogroup X capsular polysaccharide would provide useful tools for vaccine production. The serogroup X polysaccharide is a homopolymer of (α1→4)-linked N-acetylglucosamine (GlcNAc)-1-phosphate. It has been shown that the gene cluster xcbABC encodes synthesis of this polysaccharide. The xcbA gene product has significant homology with sacB, which is responsible for synthesis of the Neisseria serogroup A capsular polysaccharide, an (α1→6)-N-acetylmannosamine-1-phosphate homopolymer. The xcbA protein also shares homology with the catalytic domain of human N-acetylglucosamine-1-phosphoryltransferase, a key enzyme in the mannose-6-phosphate receptor pathway. In this study, we show that xcbA in the appropriate background is sufficient for the synthesis of N. meningitidis serogroup X polysaccharide. By ELISA we detected polysaccharide in fractions of Escherichia coli expressing the xcbA gene. We isolated polysaccharide from an E. coli strain expressing XcbA and demonstrated that this polysaccharide has a (13)C-NMR spectrum identical to that of polysaccharide isolated from N. meningitidis Group X. We also demonstrate that the purified XcbA protein is an N-acetylglucosamine-1-phosphotransferase that transfers N-acetylglucosamine-1-phosphate from UDP-GlcNAc to the 4-hydroxyl of an N-acetylglucosamine-1-phosphate oligosaccharide. Oligosaccharides fluorescently labeled at the aglycon are extended by XcbA only after the 4-phosphate occupying the non-reducing GlcNAc has been removed. The minimum size of fluorescent acceptors is a trisaccharide.

Damage control abdomen: single-stage reconstruction using a vicryl mesh buttress.

PURPOSE: Damage control laparotomy has become an accepted approach for patients with life-threatening abdominal conditions. This method compromises fascial integrity creating functionally and aesthetically debilitating hernias. The purpose of this study is to present our technique and outcomes with these complex abdominal wall reconstructions. METHODS: A retrospective review was conducted on 56 patients with previous damage control laparotomies who underwent elective single-stage abdominal wall reconstruction between 1999 and 2006. Mean age was 42 years. Reconstruction consisted of a double-layer, subfascial Vicryl mesh buttress, combined with components separation and rectus muscle turnover flaps. Hernia recurrence and function were evaluated by clinical examinations and telephone surveys. RESULTS: The major etiologies of abdominal hernias were gunshot wounds, motor vehicle accidents or blunt trauma, and sepsis or perforated bowel. The mean abdominal wall defect was 865 cm, and the average interval time to definitive repair was 17 months. The average length of follow-up was 29 months. Most patients (88%) had successful repair of their abdominal wall, with no hernia recurrence. There were 7 cases of hernia. Of these, 2 cases were from reopening of abdomen because of compartment syndrome that was not repaired, 3 were small asymptomatic hernias for which patients elected not to undergo further repair. Other complications include superficial skin dehiscence, all of which healed secondarily with daily wound care 12% (7 patients) and abdominal compartment syndrome 7.1% (4 patients), resulting in 2 postoperative mortalities in the initial part of the series. There were no mesh exposures, seromas, or fistulas. In all, 29% or 52% of patients were reached by telephone. Of those, 90% surveyed and who worked full-time prior to injury returned to their jobs, and 92% were functioning at premorbid activity levels. CONCLUSION: Massive abdominal hernia following damage control laparotomy poses a great challenge to the reconstructive surgeon. This patient population is at significant risk for mortality and morbidity. We believe the use of a Vicryl mesh buttress is an important adjunctive tool in complex abdominal wall reconstruction. Functional results are excellent with most returning to work and preinjury activity levels.