A Video-Based Procedure-Specific Competency Assessment Tool for Minimally Invasive Esophagectomy

Importance

Minimally invasive esophagectomy (MIE) is a complex procedure with substantial learning curves. In other complex minimally invasive procedures, suboptimal surgical performance has convincingly been associated with less favorable patient outcomes as assessed by peer review of the surgical procedure.

Objective

To develop and validate a procedure-specific competency assessment tool (CAT) for MIE.

Design, Setting, and Participants

In this international quality improvement study, a procedure-specific MIE-CAT was developed and validated. The MIE-CAT contains 8 procedural phases, and 4 quality components per phase are scored with a Likert scale ranging from 1 to 4. For evaluation of the MIE-CAT, intraoperative MIE videos performed by a single surgical team in the Esophageal Center East Netherlands were peer reviewed by 18 independent international MIE experts (with more than 120 MIEs performed). Each video was assessed by 2 or 3 blinded experts to evaluate feasibility, content validity, reliability, and construct validity. MIE-CAT version 2 was composed with refined content aimed at improving interrater reliability. A total of 32 full-length MIE videos from patients who underwent MIE between 2011 and 2020 were analyzed. Data were analyzed from January 2021 to January 2023.

Exposure

Performance assessment of transthoracic MIE with an intrathoracic anastomosis.

Main Outcomes and Measures

Feasibility, content validity, interrater and intrarater reliability, and construct validity, including correlations with both experience of the surgical team and clinical parameters, of the developed MIE-CAT.

Results

Experts found the MIE-CAT easy to understand and easy to use to grade surgical performance. The MIE-CAT demonstrated good intrarater reliability (range of intraclass correlation coefficients [ICCs], 0.807 [95% CI, 0.656 to 0.892] for quality component score to 0.898 [95% CI, 0.846 to 0.932] for phase score). Interrater reliability was moderate (range of ICCs, 0.536 [95% CI, -0.220 to 0.994] for total MIE-CAT score to 0.705 [95% CI, 0.473 to 0.846] for quality component score), and most discrepancies originated in the lymphadenectomy phases. Hypothesis testing for construct validity showed more than 75% of hypotheses correct: MIE-CAT performance scores correlated with experience of the surgical team (r = 0.288 to 0.622), blood loss (r = -0.034 to -0.545), operative time (r = -0.309 to -0.611), intraoperative complications (r = -0.052 to -0.319), and severe postoperative complications (r = -0.207 to -0.395). MIE-CAT version 2 increased usability. Interrater reliability improved but remained moderate (range of ICCs, 0.666 to 0.743), and most discrepancies between raters remained in the lymphadenectomy phases.

Conclusions and Relevance

The MIE-CAT was developed and its feasibility, content validity, reliability, and construct validity were demonstrated. By providing insight into surgical performance of MIE, the MIE-CAT might be used for clinical, training, and research purposes.

Remoteness from urban centre does not affect gastric cancer outcomes with established care pathway to specialist centre

BACKGROUND

Patients living in rural communities experience difficulty accessing specialized medical care. Rural patients with cancer present with more advanced disease, have reduced access to treatment and have poorer overall survival than urban patients. This study's aim was to evaluate outcomes of patients with gastric cancer living in rural and remote areas versus urban and suburban communities in the context of an established care corridor to a tertiary care centre.

METHODS

All patients treated for gastric cancer at the McGill University Health Centre during 2010-2018 were included. Travel, lodging and cancer care coordination were provided for patients from remote and rural areas and coordinated centrally by dedicated nurse navigators servicing these regions. Statistics Canada's remoteness index was used to categorize patients into a rural and remote group and an urban and suburban group.

RESULTS

A total of 274 patients were included. Compared with patients from urban and suburban areas, patients from rural and remote areas were younger and their clinical tumour stage was higher at presentation. The number of curative resections and palliative surgeries and rate of nonresection were comparable (p = 0.96). Overall, disease-free and progression-free survival were comparable between the groups, and having locally advanced cancer correlated with poorer survival (p < 0.001).

CONCLUSION

Although patients with gastric cancer from rural and remote areas had more advanced disease at presentation, their treatment patterns and survival were comparable to those of patients from urbanized areas in the context of a publicly funded care corridor to a multidisciplinary specialist cancer centre. Equitable access to health care is necessary to diminish any preexisting disparities among patients with gastric cancer.

Docetaxel-based triplet neoadjuvant therapy for esophageal adenocarcinoma: A comprehensive analysis of outcomes spanning over a decade

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Background: Docetaxel-based therapy is currently the most effective neoadjuvant regimen for locally advanced gastroesophageal adenocarcinoma. However, prior trials were primarily designed to target gastric cancer. As survival associated with taxane-based chemotherapy in esophageal adenocarcinoma (EAC) is less well described, we sought to review our experience with docetaxel based therapy as a neoadjuvant approach for EAC. Methods: A single centre retrospective review of a prospectively maintained upper GI cancer surgical database was performed (2008-2021). Patients with EAC undergoing curative intent neoadjuvant therapy with two similar docetaxel-based regimens (DCF - Docetaxel/Cisplatin/5FU or FLOT - 5FU, Leucovorin, Oxaliplatin, and Docetaxel) followed by en-bloc resection were included. Gastric/EGJ type III tumors were excluded. Clinicopathological data and overall survival (OS) were recorded and stratified by chemotherapy type (DCF vs FLOT). Data are presented as median (+/-SD). Mann-Whitney U tests for continuous or Fischer exact test for categorical variables determined significance. Kaplan-Meier curves compared OS. Results: 225 EAC patients were identified: Age 64.2 (±10.3) and tumor location was Esophageal/EGJ I/EGJ II (106/33/86). Clinical stage was cT3-4 in 201/225 (89.3%) and most were cN+ (200/225: 88.9%). There were 121 (53.7%) treated with neoadjuvant DCF whilst 104 (46.3%) received FLOT. All pre-op cycles were completed in 181 (80.4%) and did not differ between DCF and FLOT (81.8% vs 78.8% - NS). Operative procedure included Ivor Lewis in 188 (83.5%), left thoraco-abdominal esophagectomy in 20 (8.8%), and McKeown in 17 (7.5%) and also did not differ between DCF and FLOT. In terms of pathologic outcomes, the median lymph node yield was 35 (±16) of which 3.6±5.8 were positive). There was no difference when comparing between regimens. There were 134 (59.6%) patients ypN1-3 (DCF=76(62.8%) vs FLOT=58(55.8%)- NS). An R0 resection was achieved in 210 (93%) patients (DCF=92.6% vs FLOT=94.2%- NS). Complete pathological response (no residual cancer) was found in 21 patients (9.3%) (DCF=14(11.6%) vs FLOT=7(6.7%) – NS). At follow up of 41(±36) months (DCF= 52±41 vs FLOT=27±23 - p<0.001) OS (KM curve Fig 1) at 1, 3 and 5 years for the entire cohort was 91.4%, 62.8%, and 55.7%, with no difference between DCF (92.3%/68.8%/59.5%) and FLOT (89.8%/54.5%/51.7% - NS). Conclusions: This retrospective review, the largest yet reported, demonstrates that these similar docetaxel-based neoadjuvant chemotherapy regimens are highly effective for patients with locally advanced esophageal adenocarcinoma.

Treatment selection and outcomes of locally advanced esophageal cancer in octo- and nonagenarians: Is a curative intent multimodal approach feasible?

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Background: Neoadjuvant therapy followed by en bloc surgical resection affords the highest rates of survival from locally advanced esophageal cancer (LAEC) and represents the standard of care. However, patients of advanced age may not be offered this approach due to concerns over toxicity/tolerability. The outcomes of different treatment modalities for patients aged 80 and above with LAEC are not well described. Methods: A retrospective, single center, cohort analysis was performed on a prospectively maintained comprehensive esophageal cancer database. Between 2010-20, all patients ≥80yrs with locally advanced esophageal/GEJ cancer (cT2-4a, Nany, M0) were identified and outcomes stratified according to the following treatment categories: Neoadjuvant chemotherapy (nCT) or chemoradiotherapy (nCRT) followed by surgery; definitive CRT (dCRT); upfront surgery; palliative CT or RT; or best supportive care (BSC). Data presented as median(range). Univariate analysis used for clinicopathological data (*p<0.05). Survival was compared with log rank analysis (Mantel Cox). Results: 79 patients ≥80 yrs with LAEC were identified. Median age was 83yr (80-97) and Charlson comorbidity index=7 (6-10). Most were cT3 (73%), cN- (56%) and adenocarcinoma (62%). Treatment approaches included: neoadjuvant (nCT(n=11)/nCRT(N=5)) + surgery (16/79(20%)); surgery alone (19/79 (24%)); dCRT (12/29(15%)); palliative RT or CT (24 + 3/79(34%)); BSC (5/79(6%)). Neoadjuvant consisted of nCT (FLOT=4; carbo-taxol =4; FOLFOX=2; CP+pembro=1) and nCRT (CROSS=5) and most received the intended full treatment/cycles (10/16:63%). Surgery was performed in 35 (age=82(80-96)), with major complications (grade 3-5) in 13/35 (37%) and 90-day mortality in 3/35(8.5%). Overall Survival for the entire cohort was 58% (1yr) and 19% (3yr), but highest with nCT/nCRT+surgery (94%/46%)*, followed by surgery alone (68%/39%), dCRT (58%/8%), palliative treatment (40%/4%), and BSC (0%/0%). Curative intent treatment (nCT/nCRT/surgery/dCRT) had significantly increased 1 and 3-yr survival compare to palliative treatment (76%/31% vs 34%/3.3%)*. Conclusions: Multimodal standard of care treatment, including surgical resection, of locally advanced esophageal cancer in octo/nonagenarians is feasible and safe in a subset of this high-risk population and associated with improved outcomes compared to other approaches. Age alone should not bias against curative-intent treatment in elderly patients with esophageal cancer.

Treatment of anastomotic leak after esophagectomy: insights of an international case vignette survey and expert discussions

Anastomotic leak (AL) is a severe complication after esophagectomy. Clinical presentation of AL is diverse and there is large practice variation regarding treatment of AL. This study aimed to explore different AL treatment strategies and their underlying rationale. This mixed-methods study consisted of an international survey among upper gastro-intestinal (GI) surgeons and focus groups with expert upper GI surgeons. The survey included 10 case vignettes and data sources were integrated after separate analysis. The survey was completed by 188 respondents (completion rate 69%) and 6 focus groups were conducted with 20 international experts. Prevention of mortality was the most important goal of primary treatment. Goals of secondary treatment were to promote tissue healing, return to oral feeding and safe hospital discharge. There was substantial variation in the preferred treatment principles (e.g. drainage or defect closure) and modalities (e.g. stent or endoVAC) within different presentations of AL. Patients with local symptoms were treated by supportive means only or by non-surgical drainage and/or defect closure. Drainage was routinely performed in patients with intrathoracic collections and often combined with defect closure. Patients with conduit necrosis were predominantly treated by resection and reconstruction of the anastomosis or by esophageal diversion. This mixed-methods study shows that overall treatment strategies for AL are determined by vitality of the conduit and presence of intrathoracic collections. There is large variation in preferred treatment principles and modalities. Future research may investigate optimal treatment for specific AL presentations and aim to develop consensus-based treatment guidelines for AL after esophagectomy.

Development of a formative feedback tool for transanal total mesorectal excision

INTRODUCTION

Transanal total mesorectal excision (TaTME) is a novel procedure in the treatment of rectal cancer. Current training models for TaTME suggest a period of proctored cases, but no structured feedback tool exists to guide operators during the learning phase. The objective of this study therefore was to develop a formative feedback tool for the critical steps of the transanal portion of TaTME.

METHODS

A two-round Delphi study by TaTME experts was conducted to determine the items to be included in the formative feedback tool. Participants rated each step from a prepared list using a Likert scale from 1 (Not relevant) to 5 (Very relevant) with the option to suggest additional steps. Responses to the first round were presented in the second round, where participants rated the revised list of steps. Consensus was defined as > 80% of participants rating the step as 4 or 5 (out of 5). Items were combined when appropriate to avoid redundancy. Rating anchors describing performance (on a 5-point scale) were then developed for each step. The final tool was recirculated and participants rated the finished product on its feasibility and usefulness.

RESULTS

Twenty-six TaTME experts were contacted for participation. Fifteen experts (58%) participated in the first round of the study, and eleven (42%) participated in the second round. The majority (14, 93%) had completed fellowship training in colorectal surgery. The first round of the Delphi study contained 34 items, and 32 items met inclusion criteria after the second round. Redundant items were combined into 15 items that comprised the final tool. Out of eight respondents to the feasibility survey, all believed the feedback tool enhances the feedback of learners and would use it for training purposes if available.

CONCLUSION

This work describes the development of a novel consensus-based formative feedback tool specific to TaTME.

Changes in Perioperative Platelet Lymphocyte Ratio Predict Survival in Oesophago-Gastric Adenocarcinoma

BACKGROUND

Platelet to lymphocyte ratio (PLR) is associated with survival in oesophageal cancer. We explored whether PLR changes during different stages of treatment correlate with survival outcomes.

METHODS

A retrospective single-centre study was performed. Consecutive patients who received neoadjuvant chemotherapy followed by surgery for oesophageal adenocarcinoma were identified. Changes in PLR were calculated during two time periods: the first spanning the neoadjuvant period (T1); the second the perioperative period (T2). Differences in PLR were calculated for clinicopathological variables during both T1 and T2 and for variables with regards to their association with median overall survival (OS). Variables found to be significant on univariate analysis were included in a multivariate Cox regression model. Using ROC analysis, optimal cut-offs for PLR changes were identified and plotted on a Kaplan-Meir curve.

RESULTS

Of the 370 patients identified, 110 (29.7%) were included in the analysis. During T1 a positive correlation was noted between higher positive lymph node ratio and PLR change. During T2, PLR change was positively higher in patients who suffered major postoperative complications. Median survival for the cohort as a whole was 42.3 months and 5-year OS was 57.3%. Survival at 5 years was associated with lower PLR changes during T2. On univaraite analysis, median OS was significantly less for patients with a tumour size > 3 cm, poor differentiation and change in PLR ≥ 43.4 during T2. The latter two variables remained significant on multivariate analysis. Using the same PLR threshold, the survival curve comparing changes in PLR during T2 remained statistically significant.

CONCLUSION

Perioperative PLR changes are highly prognostic of survival outcomes in patients treated for oesophageal adenocarcinoma.

Reciprocal peer coaching for practice improvement in surgery: a pilot study

BACKGROUND

Peer coaching has been associated with much higher rates of practice changes and new skill implementation compared to common used modalities but bilateral peer coaching structures where seniority is not a requirement to coach have not been studied. The purpose of this study was to implement and evaluate a reciprocal peer coaching pilot program for practicing surgeons to inform future coaching program design.

METHODS

A multicenter reciprocal peer surgical coaching program was designed according to the framework developed from previous studies by our group. The coach-coachee matching process was voluntary and autonomous. All participants received basic coaching skills training. Pairs were instructed to complete two coaching sessions, alternating between the coach or coachee role for each session. Data were collected through questionnaires and structured interviews.

RESULTS

Twenty-two participants enrolled in the pilot study and completed the coach training (88% enrollment rate). During the first wave of COVID-19, 12 participants withdrew. Of the five pairs that completed the program, three pairs were composed of general surgeons, one of orthopedic surgeons, and one ophthalmologic surgeon. Three sessions were conducted live in the OR, five virtually, and one involved an in-person discussion. Overall satisfaction with the program was high and all participants expectations were met. Participants were significantly more likely to predict "routinely" asking for feedback from their partner after study completion (6, 66%) compared to pre-intervention (p = 0.02).

CONCLUSION

This pilot study supports the feasibility of a peer coaching model for surgeons in practice that emphasized reciprocity and participant autonomy. These key elements should be considered when designing future coaching programs.

Phase II trial of perioperative chemotherapy + avelumab in locally advanced gastroesophageal adenocarcinoma: Preliminary results

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Background: Perioperative chemotherapy improves cure rate in locally advanced gastroesophageal adenocarcinoma (GEA), and immune checkpoint inhibitors are active at the metastatic stage. This trial tests the hypothesis that the addition of avelumab to perioperative chemotherapy will increase the major pathologic response (MPR) rate in comparison with historical controls. Methods: Phase II study of avelumab + chemotherapy (docetaxel, cisplatin and 5-FU or mDCF) given every 2 weeks for 4 cycles before and after surgery. Main inclusion criteria: GEA, cT3 and/or cN+, M0, WHO PS 0-1. Main exclusion criteria: use of immunosuppressants, serious autoimmune disease, daily intake >10 mg prednisone. Staging studies: CT, PET-CT, endoscopic ultrasound, diagnostic laparoscopy. Surgical resection: D2 lymphadenectomy, en-bloc esophagectomy for type I/II gastroesophageal junction (GEJ) tumors. Aim of the study: MPR as defined as tumor regression grades 0-1 (modified Ryan scheme); as per hypothesis, this experimental regimen will result in a 20% rate of MPR, compared with 7% with chemotherapy alone. Simon 2-stage design: if less than 2 MPR are seen in the first 16 patients, the study will be closed. The study hypothesis cannot be rejected if at least 6 MPR are seen in the first 50 patients. All adverse effects are prospectively recorded per CTCAE guidelines in patients who have received at least one treatment cycle. Survival rates are calculated with Kaplan-Meier method. Preliminary results are presented since the study has met its primary endpoint. Results: Feb 2018-Feb 2020: 28 patients enrolled (25 M/3 F, age 45-78). Location: GEJ (23), stomach (5). Staging: cT3 (25), cT4 (1), cN+ (20). Biomarkers expression: mismatch repair (MMR) protein loss (3/28); PD-L1(clone 73-10) expression in 1% (TPS) or more of tumor cells seen in 12/28 samples, and >10% in 6 patients. Grade 3 toxicity: stomatitis (2/28); nausea (2/28); vomiting (1/28); diarrhea (1/28); hypothyroidism (1/28); arthralgia (3/28); neutropenia (1/28). Grade 4 toxicity: pneumonia (1/28); neutropenia (2/28). Postoperative 30-day mortality: 0%. One patient was excluded from efficacy analyses for M1 staging; 27 patients underwent surgery, 26 with R0 (96%). Six cases (22%) show MPR: 3 grade 0 (11%) and 3 grade 1 (11%) tumor regressions. No correlation was seen between MMR proteins or PD-L1 expression and tumor regression. With a median follow-up of 1.5 years (range 0.4-2.5), the disease-free survival rate is projected to be 0.92 (95% CI 0.83-1.00) at 12 months and 0.77 (95% CI 0.58-1.00) at 24 months. Conclusions: The combination of mDCF chemotherapy with Avelumab demonstrates a promising safety and activity profile. Ongoing laboratory investigations are underway to correlate our findings with tumor molecular features before exposure to treatment. Clinical trial information: NCT03288350.

The Effect of Preoperative Anemia and Perioperative Transfusion on Surgical Outcomes After Gastrectomy for Gastric Cancer

BACKGROUND

The aim of this study is to examine the interaction between preoperative anemia and perioperative transfusions with postoperative morbidity and mortality among patients undergoing gastrectomy for cancer.

MATERIALS AND METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was queried from 2005 to 2016. Restricted cubic splines modeled the nonlinear relationship between preoperative hematocrit (Hct) and 30-day overall morbidity, sepsis, and mortality. Preoperative Hct was categorized based on cut points for the three models. Multiple regression modeling examined the interactive effect of preoperative anemia and postoperative transfusion on surgical outcomes.

RESULTS

Among 9936 included patients, complication incidence was 38.9% (sepsis 12.7%; mortality 6.0%). Preoperative Hct cut points were identified at 29 and 42. Hct <29 was associated with higher risk of morbidity (OR 2.47, 95%CI 2.10-2.93). Postoperative transfusion was associated with lower risk of morbidity for Hct <29 (OR 0.56, 95%CI 0.43-0.73) but increased risk between 29 and 42 (OR 1.59, 95%CI 1.21-2.08). Similar relationships were found for sepsis and mortality.

CONCLUSIONS

Preoperative Hct <29 is associated with an increased risk of surgical complications after gastrectomy for cancer and perioperative transfusions appear to be beneficial for Hct <29 only. There may be a role for better optimization of red cell mass among high-risk patients before gastrectomy for cancer.

Identifying optimal program structure, motivations for and barriers to peer coaching participation for surgeons in practice: a qualitative synthesis

BACKGROUND

Continuous advancement of surgical skills is of utmost importance to surgeons in practice, but traditional learning activities without personalized feedback often do not translate into practice changes in the operating room. Peer coaching has been shown to lead to very high rates of practice changes and utilization of new skills. The purpose of this study was to explore the opinions of practicing surgeons regarding the characteristics of peer coaching programs, in order to better inform future peer coaching program design.

METHODS

Using a convenience sample, practicing general surgeons were invited to participate in focus group interviews. Allocation into groups was according to years in practice. The interviews were conducted using open-ended questions by trained facilitators. Audio recordings were transcribed and coded into themes by two independent reviewers using a grounded theory approach.

RESULTS

Of 52 invitations, 27 surgeons participated: 74% male; years in practice: < 5 years: 33%; 5-15 years: 26%; > 15 years: 41%. Three main themes emerged during coding: ideal program structure, motivations for participation, and barriers to implementation. For the ideal structure of a peer coaching program all groups agreed coaching programs should be voluntary, involve bidirectional learning, and provide CME credits. Live, in situ coaching was preferred. Motivations for coaching participation included: desire to learn new techniques (48%), remaining up to date with the evolution of surgical practice (30%) and improvement of patient outcomes (18%). Barriers to program implementation were categorized as: surgical culture (42%), perceived lack of need (26%), logistical constraints (23%) and issues of coach-coachee dynamics (9%).

CONCLUSION

Peer coaching to refine or acquire new skills addresses many shortcomings of traditional, didactic learning modalities. This study revealed key aspects of optimal program structure, motivations and barriers to coaching which can be used to inform the design of successful peer coaching programs in the future.

Implementation and Effectiveness of Coaching for Surgeons in Practice - A Mixed Studies Systematic Review

INTRODUCTION

Despite recent changes to medical education, surgical training remains largely based on the apprenticeship model. However, after completing training, there are few structured learning opportunities available for surgeons in practice to refine their skills or acquire new skills. Personalized observation with feedback is rarely a feature of traditional continuing medical education learning. Coaching has recently been proposed as a modality to meet these educational gaps; however, data are limited, and few coaching programs presently exist. The purpose of this study is to summarize the characteristics of coaching programs for surgeons in practice including participant satisfaction, program outcomes, and barriers to implementation, in the published literature.

METHODS

A mixed studies systematic review was conducted according to PRISMA guidelines to identify all original studies describing or investigating coaching for practicing surgeons up to 06/2019. Quantitative analysis was used to summarize numerical data, and qualitative analysis using grounded theory methodology for descriptive data was used to summarize the results into themes across studies.

RESULTS

After identification of articles, 27 were included in the final synthesis. Twenty-six articles described execution of a coaching program. Programs varied widely with 18/26 focusing on teaching new skills, and the remainder on refinement of skills. Thematic analysis identified 2 major data categories that guided deeper analysis: outcomes of and barriers to coaching. Of the 16 (62%) programs that reported outcomes of coaching, 42% to 100% of participants reported changes in clinical practice directly associated with coaching. Positive satisfaction after completion of a program was reported by 82% to 100% of participants. Reported barriers to participating in a coaching program emerged along 3 main themes: logistical constraints, surgical culture, and perceived lack of need.

CONCLUSIONS

Coaching for surgeons in practice is highly rated by participants and often results in clinical practice changes, while cultural and logistical issues were identified as barriers to implementation. A better understanding of these factors is required to guide coaching program development and implementation.

Synchronous pulmonary and esophageal cancers: Is combined esophagectomy and anatomic lung resection appropriate?

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Background: Resection is the best treatment for both esophagus and lung cancer, however, concerns that a combined resection of synchronous lung/esophagus tumors might be associated with higher morbidity may preclude surgical therapy. We sought to review a multi-institutional experience on combined esophagus/lung cancer resections. Methods: Patients undergoing esophagectomy and those with concurrent anatomic resection for bronchogenic carcinoma between 1997-2018 at three high-volume North American centers were identified from prospectively collected databases. Combined resection cases (E+L) were matched in a 1:3 ratio to patients who underwent esophagectomy alone (E), based on age, sex, stage, neoadjuvant therapy, procedure (2/3hole), and approach (MIE/open). Patient demographics, tumour characteristics, and post-operative outcomes were compared. Statistical analysis was performed using unpaired t-test or Wilcoxon sum-rank test for continuous variables and Fisher’s exact test for categorical data. Statistical significance was defined as p < 0.05. Results: Of over 2500 patients undergoing esophagectomy, synchronous anatomic lung resection was performed in 20; 4 were excluded due to incomplete data (n = 16). Matching yielded 48 patients and 4 duplicates were removed (n = 44); there were no significant differences in patient demographics, neoadjuvant therapy, clinical stage, or procedure. Anatomic resection consisted of lobectomy (16/20), segmentectomy (3/20) and pneumonectomy (1/20), combined with 2-hole (14/20), 3-hole (4/20), or left thoraco-abdominal (2/20) esophagectomy. The proportion of patients with any complication in E+L was 50%, and 66% in E (p = 0.42). Pulmonary complications were 19% and 27% in the respective groups (p = 0.74). Mortality did not differ (E+L = 0/16:E = 1/44)NS. The median length of stay for both groups was similar (E+L = 10.5 days(IQR 5.7): E = 10.0 days (IQR 8.7))NS. Conclusions: Patients with synchronous localized lung and esophageal cancer, although rare, should not be biased towards non-surgery therapy, as the morbidity associated with combined esophagectomy and anatomic lung resection does not differ significantly from esophagectomy alone.

Comparison of Dor and Nissen fundoplication after laparoscopic paraesophageal hernia repair

BACKGROUND

Fundoplication is performed routinely during laparoscopic repairs of a paraesophageal hernia, but the degree of fundoplication remains controversial. The purpose of this study is to assess postoperative dysphagia and reflux after a Dor versus a Nissen fundoplication in patients undergoing laparoscopic repair of giant paraesophageal hernias.

METHODS

We performed a retrospective cohort study of all patients undergoing laparoscopic repair of giant paraesophageal hernias with Nissen or Dor fundoplication between January 2012 and December 2017 at a high-volume center, excluding revisional and emergency cases. Primary outcomes were reflux and dysphagia at 1 and 6 months. Severe dysphagia was defined as intolerance to liquids. Balanced cohorts were created using coarsened exact matching.

RESULTS

A total of 106 patients were included, and 87 were matched (Dor = 48, Nissen = 58). Baseline characteristics were well balanced between matched groups. Mean follow-up duration was 17.7 months (standard deviation 16.4). The incidence of severe dysphagia at 1 month was less in the Dor group (0 of 48 vs 8 of 58, P = .02) with similar reflux symptoms. There was no difference in severe dysphagia and reflux symptoms at 6 months and at the latest visit.

CONCLUSION

Dor fundoplication is associated with less severe, early postoperative dysphagia. Future studies assessing the relative importance of dysphagia and reflux on quality of life should be conducted to tailor the operative technique and optimize patient satisfaction.

Sentinel Lymph Node Sampling for Early Gastric Cancer-Preliminary Results of A North American Prospective Study

INTRODUCTION

Although endoscopic resection for early gastric cancer is well established, anatomical resection with regional lymphadenectomy is recommended for lesions at high risk for occult lymph node metastasis (e.g., lymphovascular invasion, poor grade, and deep submucosal invasion). However, 75-95% high-risk early gastric cancer (HR-EGC) patients ultimately have node-negative disease and could potentially have undergone organ-sparing resection. Due to the inadequacy of standard modalities to reliably rule out nodal metastases in HR-EGC patients, sentinel lymph node (SLN) sampling was developed in Asia with promising results. However, the applicability of this technique in the West has been brought into question due to potential differences in tumor histology and body habitus. This prospective study aimed to test SLN sampling for North American EGC patients.

METHODS

All patients with biopsy-confirmed T0-2 N0-1 M0 gastric adenocarcinoma at the Montreal General Hospital-McGill University Health Centre were eligible for enrollment. Esophageal and GEJ cancers were excluded due to the high rate of intrathoracic lymph node involvement. Peritumoral submucosal injection with T⁹⁹ radiocolloid was performed endoscopically 24-30 h prior to surgery. Methylene blue dye injection was performed after induction of anesthesia. SLN basins were identified as those having > 10% of baseline tumor radiation signal or blue color, or both. After basins were individually removed, standard laparoscopic anatomical resection was then performed with D2 lymphadenectomy. ( ClinicalTrials.gov identifier: NCT03049345). Data are presented as median (interquartile range).

RESULTS

From July 2016-April 2018, 253 patients with esophagogastric adenocarcinoma were evaluated. Of these, 10 met inclusion criteria (90% male, age 66(30) years). Subtotal gastrectomy was performed in nine patients (90%) and length of stay was 4 (2) days. At least one SLN basin was identified in nine cases (90%). The median #SLN basins identified was 2(2) with a median of 5(5) total SLNs retrieved per patient. In the one case for which no SLN basins were identified, only blue dye injection was used, whereas SLNs were identified in all cases using the dual tracer method. Final T-stage was pT1b/T2 in four (40%), pT1a in two (20%), and Tx in four (40%). Two patients (20%) had lymph node metastases on final pathological analysis, both of which were identified by SLN sampling (accuracy 100%; false negative rate 0%). No adverse events related to SLN retrieval were identified.

CONCLUSIONS

This study represents the first prospective feasibility evaluation of sentinel lymph node sampling for early gastric cancer in North America with promising preliminary results. The dual tracer method was superior to single agent blue dye in identifying sentinel nodal basins. Considerable further study is necessary to verify the safety and utility of SLN mapping in North American patients with early gastric adenocarcinoma.

Multivisceral Resection for Locally Advanced Gastric and Gastroesophageal Junction Cancers-11-Year Experience at a High-Volume North American Center

INTRODUCTION

The oncologic benefit of multivisceral en bloc resections for T4 gastroesophageal tumors has been questioned, given the increased morbidity associated. We thus sought to investigate the surgical and oncologic outcomes of curative-intent en bloc multivisceral resections for T4 gastroesophageal carcinomas.

METHODS

Between 2005 and 2016, 35 of the 525 patients who had gastric or EGJ carcinomas underwent curative-intent multivisceral resections for direct invasion or adhesion to adjacent organs.

RESULTS

Postoperative complications occurred in 16(46%), 10 of which were Clavien-Dindo ≥ 3 (29%). Ninety-day mortality was 3%. The R0 resection rate was 94% (33). Direct organ invasion (pT4b) was confirmed on pathological analysis in 14 (40%) and did not affect survival. The majority (28, 80%) had lymph node involvement with a high nodal disease burden and was associated with decreased survival. Overall 5-year survival rate was 34%, and the vast majority of recurrences were distant/peritoneal (81%). On multivariate analysis, positive lymph nodes (H.R. 21.2; 95%CI 2.34-192) and R1 resection (H.R. 5.6; 95%CI 1.02-30.9) were predictors of survival.

CONCLUSION

Multivisceral resections for T4 gastric and GEJ adenocarcinomas, in combination with effective systemic therapy, result in prolonged long-term survival with acceptable morbidity. Complete resection to negative margins should remain a mainstay of curative-intent treatment in carefully selected patients.

The prognostic role of neutrophil-to-lymphocyte ratio trends during therapy in esophageal cancer

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Background: Neutrophil-to-lymphocyte ratio (NLR) has been identified as a biomarker for a number of malignancies, with higher ratios being associated with poorer oncologic outcomes. Rather than purely an indicator of advanced disease there is emerging evidence that neutrophils are directly implicated in facilitating cancer progression, and thus alterations and trends of neutrophil counts and NLR during different phases of treatment may reflect a change in oncologic outcome that is as important, or more so, as the absolute count or NLR at baseline. The aim of this study is to investigate the prognostic role of neutrophil-to-lymphocyte ratio trends during the treatment trajectory of patients with esophageal adenocarcinoma. Methods: This is a retrospective study of patients who underwent esophagectomy for esophageal adenocarcinoma between 2005-2016. NLR was measured at three time points: baseline, during neoadjuvant chemotherapy (NAC), and in the late postoperative period. Primary outcomes were overall (OS) and disease-free survival (DFS). Results: 333 patients met our inclusion criteria. Mean age was 65.6 years and 82% of patients were males. The majority of patients had locally advanced disease; 75% had clinical T3 disease and 59% had clinical N-positive disease. NAC was administered in 65.6% of patients. Increasing NLR trends between baseline and late postoperative periods was associated with worse OS (3-year OS 56.1% vs. 71.9%, p=0.045). Patients in the high NLR group before and after treatment did worse than those who moved from high to low groups (3-year OS 42.8% vs. 69.2%, p=<0.0001, 3-year DFS 32.3% vs. 61.8%, p=0.0001). High NLR at baseline and in the postoperative stage is associated with worse OS (3-year OS: 57% vs. 75.7% for baseline and 44.1% vs. 74.9% for postoperative NLR; p=0.0038 and <0.0001, respectively) and DFS (3-year DFS: 52.4% vs. 60.9% for baseline and 34.9% vs. 59.9% for postoperative NLR; p=0.03 and <0.0001, respectively). Patients with complete pathological response to NAC had lower mean baseline NLR (3.2 vs. 4.9 p=0.009). Conclusions: Changes in NLR during treatment may provide a clearer picture about survival outcomes and the role of neutrophils in cancer progression.

Enrollment of esophago-gastric cancer patients in a clinical fast-track program and it’s affect on time to treatment and quality of life

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Background: Esophago-gastric cancers are aggressive malignancies requiring numerous investigations to plan complex multi-modal therapy. The path from initial diagnosis to treatment can be associated with a long delay. This delay and complex patient trajectory may impact quality of life. Given the poor prognosis and highly symptomatic nature of upper GI cancer, a clear and timely access to treatment of crucial importance. We sought to determine the impact of a newly implemented streamlined and structure interdisciplinary pathway for newly diagnosed esophageal and gastric cancer on access times to treatment and quality of life (QoL). Methods: A streamlined pathway for patients referred to a high volume Upper GI Cancer clinic was generated with input from physicians, nutritionists, specialized nurses, and social workers. New diagnosis of esophageal or gastric cancer from 2014-16 were enrolled in this program and consenting patients completed serial QoL questionnaires (ESAS) at baseline, pre-treatment, 1 month post treatment. Dysphagia (DS) was quantified on a 5 point scale. Time intervals (days) were evaluated at various points between diagnosis and start of treatment (diagnosis, CT imaging, first visit with upper GI program, start of treatment). Data presented as median(IQR), * p < 0.05. Results: Of the 251 patients with Upper GI cancer, 153 (61%) consented to participate including 140 esophageal/EGJ and 13 gastric cancer patients. Clinical stage distribution was 17.9% I, 30.7% II, 42.6% III, 8.7% IV. Of the 82 Esoph/EGJ patients with completed QoL questionnaires, 15 (18.3%) patients had severe dysphagia (DS = 3-4) and were prioritized for treatment. Patients with severe dysphagia had reduced time from index endoscopy to treatment (29 (16.3-39.3) vs 43 (32.8-68.0)days)* and first Upper GI clinic to treatment (15 (8.0-23.0) vs 25 (21.0-36.0)*. ESAS surveys showed increased QoL for both patients with and without dysphagia from baseline to pre-treatment indicating that simply entry into the streamlined program improved QoL. Conclusions: Structured interdisciplinary investigative and treatment programs for upper GI cancers can expedite time to treatment and improve QoL.

The Steinberg Centre for Simulation and Interactive Learning at McGill University

Simulation allows for learner-centered health professions training by providing a safe environment to practice and make mistakes without jeopardizing patient care. It was with this goal in mind that the McGill Medical Simulation Center was officially opened on September 14, 2006, as a partnership between McGill University, the Faculty of Medicine and its affiliated hospitals. Its mandate is to provide state-of-the-art facilities to support simulation-based medical and allied health education initiatives. Since its inception, the center, recently renamed the Steinberg Center for Simulation and Interactive Learning (SCSIL), has undergone a major expansion and logged more than 130,000 learner visits. Educational activities are offered at all levels of medical and allied health care training, and include standardized patient encounters, partial task trainers, multidisciplinary courses, and high-fidelity trainers, among many others. In addition to its educational mandate, the center also supports an active research program, programs to enhance collaboration with disciplines outside of health care to spur innovation, and community outreach initiatives.

Same day discharge for benign laparoscopic hiatal surgery: a feasibility analysis

BACKGROUND

Advances in minimally invasive surgery and the development of enhanced recovery pathways have favored the spread of day-surgery programs. Despite laparoscopic approaches being accepted as the standard of care for benign hiatal diseases, safety and feasibility of same day discharges for laparoscopic hiatal surgeries other than fundoplication has yet to be established.

OBJECTIVE

This study aimed to assess the feasibility of same day discharge for primary and revisional laparoscopic hiatal surgeries including paraesophageal hernia repairs (PEHR), fundoplication for reflux, and Heller myotomy (±diverticulectomy).

METHODS

A retrospective cohort study including all patients undergoing elective laparoscopic hiatal procedures in the division of Thoracic surgery between 2011 and 2016 at McGill University Health Centre was performed. Planned day-surgery (DAYCASE) was compared to planned inpatient (INPATIENT) cohorts with respect to operative and postoperative outcomes, length of stay, readmission, and emergency room visits.

RESULTS

A total of 261 patients were identified, 161 female (62%); median age 62 (20). The case distribution was: PEHR (123; 47.1%), Heller myotomy (94;36%, 7 diverticulectomy), and fundoplication (44; 16.9%). Twenty patients had revisional procedures (7.7%). Same day discharge was planned in 98 cases (38%) and was successful in 80 (81.6%). Proportion of DAYCASE increased form 12% prior to 2013 to 67% in 2016. INPATIENTs were older (median 66 vs. 60 years), and had a higher proportion of PEHR (55 vs. 34%), p < 0.05. Both cohorts were comparable in gender proportion, ASA classification, and length of surgery. Complications, readmission, and emergency visits did not differ between the two cohorts. On multivariate analysis, female gender (OR 37, 95% CI 1.46-936, p = 0.028), surgery beginning after noon (OR 5.4, 95% CI 1.1-26.9, p = 0.038), intraoperative complications (OR 20.4 95% CI 1.5-286, p = 0.025), and postoperative complications (OR 52.1, 95% CI 4.5-602, p = 0.002) were independently associated with unplanned admission.

CONCLUSIONS

Day-case surgery for complex laparoscopic hiatal procedures is feasible and can be achieved in a significant number of patients without compromising safety.

Small optic suspensions for Advanced LIGO input optics and other precision optical experiments

We report on the design and performance of small optic suspensions developed to suppress seismic motion of out-of-cavity optics in the input optics subsystem of the Advanced Laser Interferometer Gravitational Wave Observatory. These compact single stage suspensions provide isolation in all six degrees of freedom of the optic, local sensing and actuation in three of them, and passive damping for the other three.

Application of an individualized operative strategy for wedge resection of gastric gastrointestinal stromal tumors: Effectiveness for tumors in difficult locations

BACKGROUND

There is some concern that wedge resection of gastric gastrointestinal stromal tumors is not feasible in certain anatomic locations, such as the cardia or antrum. We sought to review our experience with treatment of gastric gastrointestinal stromal tumors with a particular focus on nonanatomic wedge resections in these challenging locations.

METHODS

Patients undergoing resection of gastrointestinal stromal tumors from 2000-2014 at the Montreal General Hospital were identified from a prospectively collected database, and outcomes were tabulated. An individualized operative strategy was used to guide resection based on tumor location, size, and characteristics. Disease-free survival and overall survival analyzed using the Kaplan-Meier method. Data are presented as median (range).

RESULTS

We identified 59 patients who underwent operative resection for gastric gastrointestinal stromal tumors. Tumor location was fundus/body/greater curvature in 35 (59%) patients, lesser curvature in 8 (14%) patients, antrum in 8 (14%) patients, and cardia in 8 (14%) patients. Median tumor size was 4.5 cm (1.4-25 cm). The majority of cardia and antral lesions were removed with wedge resections (14/16, 87%). For cardial and antral tumors, on-table gastroscopy was used to guide the operative approach and prevent narrowing of the Gastroesophageal junction or pylorus in all patients undergoing wedge resection. Negative pathologic margins were achieved in all patients. The 5-year disease-free survival was 91% and 5-year overall survival was 95%.

CONCLUSION

When selected appropriately, and under the guidance of on-table gastroscopy, laparoscopic nonanatomic wedge resection can be performed successfully in the majority of cases, even for gastrointestinal stromal tumors near the GEJ or pylorus, with excellent oncologic outcomes.

Characterization of transient noise in Advanced LIGO relevant to gravitational wave signal GW150914

On September 14, 2015, a gravitational wave signal from a coalescing black hole binary system was observed by the Advanced LIGO detectors. This paper describes the transient noise backgrounds used to determine the significance of the event (designated GW150914) and presents the results of investigations into potential correlated or uncorrelated sources of transient noise in the detectors around the time of the event. The detectors were operating nominally at the time of GW150914. We have ruled out environmental influences and non-Gaussian instrument noise at either LIGO detector as the cause of the observed gravitational wave signal.

Properties of the Binary Black Hole Merger GW150914

On September 14, 2015, the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected a gravitational-wave transient (GW150914); we characterize the properties of the source and its parameters. The data around the time of the event were analyzed coherently across the LIGO network using a suite of accurate waveform models that describe gravitational waves from a compact binary system in general relativity. GW150914 was produced by a nearly equal mass binary black hole of masses 36_{-4}^{+5}M_{⊙} and 29_{-4}^{+4}M_{⊙}; for each parameter we report the median value and the range of the 90% credible interval. The dimensionless spin magnitude of the more massive black hole is bound to be <0.7 (at 90% probability). The luminosity distance to the source is 410_{-180}^{+160}  Mpc, corresponding to a redshift 0.09_{-0.04}^{+0.03} assuming standard cosmology. The source location is constrained to an annulus section of 610  deg^{2}, primarily in the southern hemisphere. The binary merges into a black hole of mass 62_{-4}^{+4}M_{⊙} and spin 0.67_{-0.07}^{+0.05}. This black hole is significantly more massive than any other inferred from electromagnetic observations in the stellar-mass regime.

GW150914: First results from the search for binary black hole coalescence with Advanced LIGO

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) simultaneously observed the binary black hole merger GW150914. We report the results of a matched-filter search using relativistic models of compact-object binaries that recovered GW150914 as the most significant event during the coincident observations between the two LIGO detectors from September 12 to October 20, 2015. GW150914 was observed with a matched filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203000 years, equivalent to a significance greater than 5.1 σ.

GW150914: First results from the search for binary black hole coalescence with Advanced LIGO

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) simultaneously observed the binary black hole merger GW150914. We report the results of a matched-filter search using relativistic models of compact-object binaries that recovered GW150914 as the most significant event during the coincident observations between the two LIGO detectors from September 12 to October 20, 2015. GW150914 was observed with a matched filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203000 years, equivalent to a significance greater than 5.1 σ.

Tests of General Relativity with GW150914

The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant's mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 10^{13}  km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.

GW150914: Implications for the Stochastic Gravitational-Wave Background from Binary Black Holes

The LIGO detection of the gravitational wave transient GW150914, from the inspiral and merger of two black holes with masses ≳30M_{⊙}, suggests a population of binary black holes with relatively high mass. This observation implies that the stochastic gravitational-wave background from binary black holes, created from the incoherent superposition of all the merging binaries in the Universe, could be higher than previously expected. Using the properties of GW150914, we estimate the energy density of such a background from binary black holes. In the most sensitive part of the Advanced LIGO and Advanced Virgo band for stochastic backgrounds (near 25 Hz), we predict Ω_{GW}(f=25  Hz)=1.1_{-0.9}^{+2.7}×10^{-9} with 90% confidence. This prediction is robustly demonstrated for a variety of formation scenarios with different parameters. The differences between models are small compared to the statistical uncertainty arising from the currently poorly constrained local coalescence rate. We conclude that this background is potentially measurable by the Advanced LIGO and Advanced Virgo detectors operating at their projected final sensitivity.

GW150914: The Advanced LIGO Detectors in the Era of First Discoveries

Following a major upgrade, the two advanced detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) held their first observation run between September 2015 and January 2016. With a strain sensitivity of 10^{-23}/sqrt[Hz] at 100 Hz, the product of observable volume and measurement time exceeded that of all previous runs within the first 16 days of coincident observation. On September 14, 2015, the Advanced LIGO detectors observed a transient gravitational-wave signal determined to be the coalescence of two black holes [B. P. Abbott et al., Phys. Rev. Lett. 116, 061102 (2016)], launching the era of gravitational-wave astronomy. The event, GW150914, was observed with a combined signal-to-noise ratio of 24 in coincidence by the two detectors. Here, we present the main features of the detectors that enabled this observation. At full sensitivity, the Advanced LIGO detectors are designed to deliver another factor of 3 improvement in the signal-to-noise ratio for binary black hole systems similar in mass to GW150914.

Observation of Gravitational Waves from a Binary Black Hole Merger

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10(-21). It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410(-180)(+160)  Mpc corresponding to a redshift z=0.09(-0.04)(+0.03). In the source frame, the initial black hole masses are 36(-4)(+5)M⊙ and 29(-4)(+4)M⊙, and the final black hole mass is 62(-4)(+4)M⊙, with 3.0(-0.5)(+0.5)M⊙c(2) radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.

Validity evidence for a new portable, lower-cost platform for the fundamentals of endoscopic surgery skills test

BACKGROUND

The fundamentals of endoscopic surgery (FES) examination measures the knowledge and skills required to perform safe flexible endoscopy. A potential limitation of the FES skills test is the size and cost of the simulator on which it was developed (GI Mentor II virtual reality endoscopy simulator; Simbionix LTD, Israel). A more compact and lower-cost alternative (GI Mentor Express) was developed to address this issue. The purpose of this study was to obtain evidence for the validity of scores obtained on the Express platform, so that it can be used for testing.

STUDY DESIGN

General surgery residents at various levels of training and practicing endoscopists at five institutions participated. Each completed the five FES tasks on both simulator platforms in random order, with 3-14 days between tests. Scores were calculated using the same standardized computer-generated algorithm and compared using Pearson's correlation coefficient.

RESULTS

There were 58 participants (mean age 32; 76% male) with a broad range of endoscopic experience. The mean (95% confidence interval) FES scores were 72 (67:77) on the GI Mentor II and 66 (60:71) on the Express. The correlation between scores on the two platforms was 0.86 (0.77:0.91; p < 0.0001).

CONCLUSION

There is a high correlation between FES manual skills scores measured on the original platform and the new Express, providing evidence to support the use of the GI Mentor Express for FES testing.

Improved upper limits on the stochastic gravitational-wave background from 2009-2010 LIGO and Virgo data

Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of Ω_{GW}(f)=Ω_{α}(f/f_{ref})^{α}, we place 95% confidence level upper limits on the energy density of the background in each of four frequency bands spanning 41.5-1726 Hz. In the frequency band of 41.5-169.25 Hz for a spectral index of α=0, we constrain the energy density of the stochastic background to be Ω_{GW}(f)<5.6×10^{-6}. For the 600-1000 Hz band, Ω_{GW}(f)<0.14(f/900  Hz)^{3}, a factor of 2.5 lower than the best previously reported upper limits. We find Ω_{GW}(f)<1.8×10^{-4} using a spectral index of zero for 170-600 Hz and Ω_{GW}(f)<1.0(f/1300  Hz)^{3} for 1000-1726 Hz, bands in which no previous direct limits have been placed. The limits in these four bands are the lowest direct measurements to date on the stochastic background. We discuss the implications of these results in light of the recent claim by the BICEP2 experiment of the possible evidence for inflationary gravitational waves.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

Constraints on cosmic strings from the LIGO-Virgo gravitational-wave detectors

Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we present a search for GWs from cosmic string cusps in data collected by the LIGO and Virgo gravitational wave detectors between 2005 and 2010, with over 625 days of live time. We find no evidence of GW signals from cosmic strings. From this result, we derive new constraints on cosmic string parameters, which complement and improve existing limits from previous searches for a stochastic background of GWs from cosmic microwave background measurements and pulsar timing data. In particular, if the size of loops is given by the gravitational backreaction scale, we place upper limits on the string tension Gμ below 10(-8) in some regions of the cosmic string parameter space.

Linear-stapled gastrojejunostomy with transverse hand-sewn enterotomy closure significantly reduces strictures for laparoscopic Roux-en-Y gastric bypass

BACKGROUND

Gastrojejunostomy (GJ) stricture is a common complication after Roux-en-Y gastric bypass (RYGB) for morbid obesity, and the optimal anastomotic technique remains uncertain. The objective of this study was to use cumulative summation (CUSUM) analysis to compare rates of gastrojejunostomy strictures after linear stapling with longitudinal versus transverse enterotomy closure in gastric bypass patients.

METHODS

Charts of all consecutive patients with at least 60 days of post-operative follow-up after laparoscopic RYGB (LRYGB) at our tertiary care institution from Nov 2009 to Dec, 2011 were retrospectively reviewed. Gastrojejunostomy stricture was diagnosed by history and upper endoscopy. CUSUM method of quality control analysis was used to determine sequential improvement in stricture rates with the change in technique.

RESULTS

A total of 197 patients were included (97 longitudinal closure, median age 44 (21-67), median BMI 47 (35-80), 85.8 % female). Gastrojejunostomy strictures occurred in 16 % of longitudinal and 0 % of transverse patients (p = <0.0001). CUSUM analysis demonstrated sequential statistically significant improvement in stricture rates after the change in technique was applied. The longitudinal group had a statistically significant increased rate of surgery-related readmissions (15.5 vs 6.0 %, p = 0.038), with 43.7 % of those readmissions related to GJ strictures. There were no other significant outcome differences between groups.

CONCLUSIONS

Linear-stapled anastomosis with a transverse enterotomy closure significantly reduces the rate of gastrojejunostomy stricture for LRYGB, considerably reducing procedural morbidity.

Outcomes reported in high-impact surgical journals

Background

With advances in operative technique and perioperative care, traditional endpoints such as morbidity and mortality provide an incomplete description of surgical outcomes. There is increasing emphasis on the need for patient-reported outcomes (PROs) to evaluate fully the effectiveness and quality of surgical interventions. The objective of this study was to identify the outcomes reported in clinical studies published in high-impact surgical journals and the frequency with which PROs are used.

Methods

Electronic versions of material published between 2008 and 2012 in the four highest-impact non-subspecialty surgical journals (Annals of Surgery, British Journal of Surgery (BJS), Journal of the American College of Surgeons (JACS), Journal of the American Medical Association (JAMA) Surgery) were hand-searched. Clinical studies of adult patients undergoing planned abdominal, thoracic or vascular surgery were included. Reported outcomes were classified into five categories using Wilson and Cleary's conceptual model.

Results

A total of 893 articles were assessed, of which 770 were included in the analysis. Some 91·6 per cent of studies reported biological and physiological outcomes, 36·0 per cent symptoms, 13·4 per cent direct indicators of functional status, 10·6 per cent general health perception and 14·8 per cent overall quality of life (QoL). The proportion of studies with at least one PRO was 38·7 per cent overall and 73·4 per cent in BJS (P &lt; 0·001). The proportion of studies using a formal measure of health-related QoL ranged from 8·9 per cent (JAMA Surgery) to 33·8 per cent (BJS).

Conclusion

The predominant reporting of clinical endpoints and the inconsistent use of PROs underscore the need for further research and education to enhance the applicability of these measures in specific surgical settings.

Identification of essential operons with a rhamnose-inducible promoter in Burkholderia cenocepacia

Scanning of bacterial genomes to identify essential genes is of biological interest, for understanding the basic functions required for life, and of practical interest, for the identification of novel targets for new antimicrobial therapies. In particular, the lack of efficacious antimicrobial treatments for infections caused by the Burkholderia cepacia complex is causing high morbidity and mortality of cystic fibrosis patients and of patients with nosocomial infections. Here, we present a method based on delivery of the tightly regulated rhamnose-inducible promoter P(rhaB) for identifying essential genes and operons in Burkholderia cenocepacia. We demonstrate that different levels of gene expression can be achieved by using two vectors that deliver P(rhaB) at two different distances from the site of insertion. One of these vectors places P(rhaB) at the site of transposon insertion, while the other incorporates the enhanced green fluorescent protein gene (e-gfp) downstream from P(rhaB). This system allows us to identify essential genes and operons in B. cenocepacia and provides a new tool for systematically identifying and functionally characterizing essential genes at the genomic level.

Phenotypic analysis of Paf1/RNA polymerase II complex mutations reveals connections to cell cycle regulation, protein synthesis, and lipid and nucleic acid metabolism

Paf1 is an RNA polymerase II-associated protein in yeast, which defines a complex that is distinct from the Srb/Mediator holoenzyme. The Paf1 complex, which also contains Ctr9, Cdc73, Hpr1, Ccr4, Rtf1 and Leo1, is required for full expression of a subset of yeast genes, particularly those responsive to signals from the Pkc1/MAP kinase cascade. We have extensively characterized the pleiotropic phenotypes of deletion mutants for factors present in the Paf1 complex, identifying more than a dozen new phenotypes, and, in some cases, establishing possible molecular explanations for the growth defects. For example, paf1 Delta causes sensitivity to hydroxyurea; this phenotype correlates with a reduction in RNR1 transcript abundance and is suppressed by over-expression of RNR1. In contrast, the resistance of paf1 Delta cells to the transcription elongation inhibitors 6-azauracil and mycophenolic acid correlates with its ability to derepress the IMD2 transcript. We tested the hypothesis that Paf1 communicates with some promoters through the DNA-binding factors Swi4, Mbp1 or Rlm1. The phenotypes of mutations in Paf1 complex components are exacerbated in the swi4 Delta background, suggesting that the complex acts in a pathway parallel to that controlled by Swi4. Conversely, the fact that mbp1 Delta and rlm1 Delta mutations do not enhance the phenotypes suggests that the Paf1 complex may function in the same regulatory pathway(s) with Mbp1 and Rlm1.

A challenge for nursing education

Computer technology has the potential to help nursing programs to establish conditions that allow for academic success of special needs students without compromising the caliber of instruction or academic standards. As the capabilities of computers have increased in the last decade, a variety of exciting new tools have been created that have the potential to enhance the success of students with special needs. Effective instructional methods must be developed and implemented to make use of the power provided by these tools. Limited research is available in the nursing and education literature to support use of computer adaptations for students with special needs. There needs to be initiation of research based study of the tools and proposed adaptations. Educators, administrators, and researchers need to collaborate in this effort to transform the potential of technology into reality.

CREB-binding protein activates transcription through multiple domains

CREB-binding protein (CBP) functions as a coactivator molecule for a number of transcription factors including CREB, c-Fos, c-Jun, c-Myb, and several nuclear receptors. Although binding sites for these factors within CBP have been identified, the regions of CBP responsible for transcriptional activation are unknown. In this report, we show that the N-terminal half of CBP is sufficient for activation of CREB-mediated transcription and that this region contains a strong transcriptional activation domain (TAD). Both deletion of this TAD or sequestering of factors that the TAD binds using a squelching assay were found to greatly decrease the ability of CBP to activate CREB-mediated transcription. In vivo studies by others have shown that p300/CBP associates with TBP; using an in vitro approach, we show the N-terminal TAD binds TBP. We also examined the ability of the C terminus of CBP to activate transcription using GAL-CBP chimeras. With this approach, we identified two C-terminal TADs located adjacent to the c-Fos binding site. In previous studies, cAMP-dependent protein kinase A (PKA) increased the transcriptional activity of a GAL full-length CBP chimera in F9 cells, and of the C terminus in PC-12 cells. Here, we demonstrate that PKA also increased the ability of the N-terminal TADs of CBP to activate transcription in PC-12 but not F9 or COS-7 cells, suggesting that this PKA-responsiveness is cell type-specific.