Stanley W Ashley

Harvard Medical School, Boston, Massachusetts, United States

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Publications (284)1323.8 Total impact

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    ABSTRACT: The latest studies on surgical and cost-analysis outcomes after laparoscopic distal pancreatectomy (LDP) highlight mixed and insufficient results. Whereas several investigators have compared surgical outcomes of LDP vs. open distal pancreatectomy (ODP) for adenocarcinomas, few similar studies have focused on pancreatic neuroendocrine tumors (PNETs). We reviewed the medical records of PNET patients undergoing distal pancreatectomy between 2004 and 2014. Patients were divided into LDP vs. ODP groups. Demographics, relevant comorbidities, oncologic variables, and cost-analysis data were assessed. Survival and Cox proportional hazards analyses were used to evaluate outcomes. Of the 171 distal pancreatectomies for PNETs, 73 were laparoscopic, whereas 98 were open. Patients undergoing LDP demonstrated significantly lower rates of postoperative complications (P = 0.028) and had significantly shorter hospital stays (P = 0.008). On multivariable analysis, positive resection margins (P = 0.046), G3 grade (P = 0.036), advanced WHO classification (P = 0.016), TNM stage (P = 0.018), and readmission (P = 0.019) were significantly associated with poor survival; however, method of resection (LDP vs. ODP) was not (P = 0.254). The median total direct costs of LDP vs. ODP did not differ significantly. In response to the recent considerable controversy surrounding the costs and surgical outcomes of LDP vs. ODP, our results show that LDP for PNETs is cost-neutral and significantly reduces postoperative morbidity without compromising oncologic outcomes and survival.
    Journal of Gastrointestinal Surgery 03/2015; 19(5). DOI:10.1007/s11605-015-2788-1 · 2.80 Impact Factor
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    ABSTRACT: Although surveillance guidelines for resected invasive mucinous neoplastic cysts are well-established, those for noninvasive cysts are not defined. We used our experience with resected noninvasive mucinous neoplastic cysts to define recurrence rates and the optimal frequency of postoperative imaging follow-up. We reviewed the medical records of 134 patients with resected, pathologically confirmed noninvasive mucinous neoplasms between 2002 and 2012. Demographics, comorbidities, cyst characteristics, and recurrence were evaluated. Survival analysis was used to estimate the distribution of time to recurrence and regression models were used to investigate factors associated with recurrence. Eighty-seven patients with intraductal papillary mucinous neoplasms (IPMNs) were compared with 47 patients with mucinous cystic neoplasms (MCNs). Those with MCNs were more often females (P = .001), significantly younger (P = .001), more symptomatic (P = .009), and had cysts more often located in the tail (P < .001). Median follow-up was 42 months. Recurrence rates for IPMNs were 0%, 5%, and 10% versus 0% for MCNs respectively at postoperative years 1, 2, and 3 (P = .014). On multivariable analysis, size >3 cm (P = .027), higher grade dysplasia (P = .043), and positive resection margins (P < .001) were significantly associated with recurrence. Resected noninvasive IPMNs with moderate- or high-grade dysplasia and negative resection margins require imaging follow-up every 2 years, given the 16% overall recurrence rate. Although the follow-up interval for noninvasive, low-grade, dysplastic IPMNs with negative margins could be lengthened, all noninvasive IPMNs having positive margins require yearly follow-up at the minimum. Resected noninvasive MCNs--irrespective of grade and margin status--do not require surveillance, although the development of branch duct-IPMNs in the remnant pancreas can be investigated in the long term at the discretion of the provider. Copyright © 2014 Elsevier Inc. All rights reserved.
    Surgery 01/2015; 157(3). DOI:10.1016/j.surg.2014.09.028 · 3.38 Impact Factor
  • Elliot Wakeam · Joseph A. Hyder · Stanley W. Ashley · Joel S. Weissman
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    ABSTRACT: Organizational factors influencing failure-to-rescue (FTR)-or death after postoperative complications-are poorly understood. Case studies were conducted to generate hypotheses that could inform future FTR research and improvement strategies. Publicly reported 2009-2011 data were used to identify 144 outlier hospitals with statistically better or worse FTR performance than the national average. Of these 144 hospitals, 7 were selected for case studies in a purposive sample. Outliers enabled a focus on the organizational factors and processes at the extremes of performance. Semi-structured interviews were conducted in 2013 with key informants at each hospital, and transcripts were analyzed using the constant comparative method to identify emergent organizational behavioral themes. The 7 hospitals-4 high- and 3 low-performing-yielded 106 interviews. Critical barriers to effective rescue were ineffective communication, lack of psychological safety, staffing discontinuity, imbalance of shared ownership and individual responsibility, lack of appropriate training and education, and difficulty using current metrics. Participants also identified strategies to overcome these barriers-rapid response teams, flattening the hierarchy, escalation strategies, health information technology, structured communication tools, constant team structures, standardized care pathways, and organizational learning. FTR is a complex process that is viewed, defined, and acted on differently across and within organizations. Early recognition of patients deviating from normal recovery was enhanced in high-performing hospitals through the use of standardized postoperative recovery pathways and automated escalation protocols. Current FTR measures may be less actionable for the purposes of quality improvement.
    Joint Commission journal on quality and patient safety / Joint Commission Resources 11/2014; 40(11). DOI:10.1016/j.jamcollsurg.2014.07.218
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    ABSTRACT: Introduction: Studies suggest that improvements in type 2 diabetes (T2D) post-RYGB surgery are due to decreased intestinal glucose absorption capacity mediated by exclusion of sweet taste sensing pathways in isolated proximal bowel. We probed these pathways in rat models that had undergone RYGB with catheter placement in the biliopancreatic (BP) limb to permit post-RYGB exposure of isolated bowel to sweet taste stimulants. Methods: Lean Sprague Dawley (SD) (n=13) and obese Zucker Diabetic Fatty (ZDF) rats (n=15) underwent RYGB with BP catheter placement. On post-operative day 11 rats received catheter infusions of saccharin (sweet taste receptor (T1R2/3) agonist) or saline (control). Jejunum was analyzed for changes in glucose transporter/ sensor mRNA expression and functional SGLT1-mediated glucose uptake. Results: Saccharin infusion did not alter glucose uptake in the Roux limb of RYGB rats. Intestinal expression of glucose sensors (T1R2, SGLT3) and transporters (SGLT1, GLUT2) was similar in saccharin- vs. saline-infused rats of both strains. However, the abundance of SGLT3b mRNA, a putative glucose sensor, was higher in the common limb vs. BP/ Roux limb in both strains of bypassed rats and was significantly decreased in the Roux limb after saccharin infusion. Conclusions: Failure of BP limb exposure to saccharin to increase Roux limb glucose uptake suggests that isolation of T1R2/3 is unlikely to be involved in metabolic benefits of RYGB as re-stimulation failed to reverse changes in intestinal glucose absorption capacity. The altered expression pattern of SGLT3 after RYGB warrants further investigation of its potential involvement in resolution of T2D after RYGB.
    AJP Gastrointestinal and Liver Physiology 07/2014; 307(5). DOI:10.1152/ajpgi.00405.2013 · 3.80 Impact Factor
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    ABSTRACT: Purpose: Critical care is often an integral part of rescue for patients with surgical complications. We sought to understand critical care characteristics predictive of failure-to-rescue (FTR) performance at the hospital level. Methods: Using 2009 to 2011 FTR data from Hospital Compare, we identified 144 outlier hospitals with significantly better/worse performance than the national average. We surveyed intensive care unit (ICU) directors and nurse managers regarding physical structures, patient composition, staffing, care protocols, and rapid response teams (RRTs). Hospitals were compared using descriptive statistics and logistic regression. Results: Of 67 hospitals completing the survey, 56.1% were low performing, and 43.9% were high performing. Responders were more likely to be teaching hospitals (40.9% vs 25.0%; P=.05) but were similar to nonresponders in terms of size, region, ownership, and FTR performance. Poor performers were more likely to serve higher proportions of Medicaid patients (68.4% vs 20.7%; P<.0001) and be level 1 trauma centers (55.9% vs 25.9%; P=.02). After controlling for these 2 characteristics, an intensivist on the RRT (adjusted odds ratio, 4.27; confidence interval, 1.45-23.02; P=.005) and an internist on staff in the ICU (adjusted odds ratio, 2.13; P=.04) were predictors of high performance. Conclusions: Intensivists on the RRT and internists in the ICU may represent discrete organizational strategies for improving patient rescue. Hospitals with high Medicaid burden fare poorly on the FTR metric.
    Journal of Critical Care 06/2014; 29(6). DOI:10.1016/j.jcrc.2014.06.010 · 2.00 Impact Factor
  • Journal of the American College of Surgeons 04/2014; 218(4):703-706. · 5.12 Impact Factor
  • A.D. Smith · M.S. De Vos · D.S. Smink · L.L. Nguyen · S.W. Ashley
    Journal of Surgical Research 02/2014; 186(2):497. DOI:10.1016/j.jss.2013.11.079 · 1.94 Impact Factor
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    ABSTRACT: IMPORTANCE Failure to rescue (FTR), the mortality rate among surgical patients with complications, is an emerging quality indicator. Hospitals with a high safety-net burden, defined as the proportion of patients covered by Medicaid or uninsured, provide a disproportionate share of medical care to vulnerable populations. Given the financial strains on hospitals with a high safety-net burden, availability of clinical resources may have a role in outcome disparities. OBJECTIVES To assess the association between safety-net burden and FTR and to evaluate the effect of clinical resources on this relationship. DESIGN, SETTING, AND PARTICIPANTS A retrospective cohort of 46 519 patients who underwent high-risk inpatient surgery between January 1, 2007, and December 31, 2010, was assembled using the Nationwide Inpatient Sample. Hospitals were divided into the following 3 safety-net categories: high-burden hospitals (HBHs), moderate-burden hospitals (MBHs), and low-burden hospitals (LBHs). Bivariate and multivariate analyses controlling for patient, procedural, and hospital characteristics, as well as clinical resources, were used to evaluate the relationship between safety-net burden and FTR. MAIN OUTCOMES AND MEASURES FTR. RESULTS Patients in HBHs were younger (mean age, 65.2 vs 68.2 years; P = .001), more likely to be of black race (11.3% vs 4.2%, P < .001), and less likely to undergo an elective procedure (39.3% vs 48.6%, P = .002) compared with patients in LBHs. The HBHs were more likely to be large, major teaching facilities and to have high levels of technology (8.6% vs 4.0%, P = .02), sophisticated internal medicine (7.7% vs 4.3%, P = .10), and high ratios of respiratory therapists to beds (39.7% vs 21.1%, P < .001). However, HBHs had lower proportions of registered nurses (27.9% vs 38.8%, P = .02) and were less likely to have a positron emission tomographic scanner (15.4% vs 22.0%, P = .03) and a fully implemented electronic medical record (12.6% vs 17.8%, P = .03). Multivariate analyses showed that HBHs (adjusted odds ratio, 1.35; 95% CI, 1.19-1.53; P < .001) and MBHs (adjusted odds ratio, 1.15; 95% CI, 1.05-1.27; P = .005) were associated with higher odds of FTR compared with LBHs, even after adjustment for clinical resources. CONCLUSIONS AND RELEVANCE Despite access to resources that can improve patient rescue rates, HBHs had higher odds of FTR, suggesting that availability of hospital clinical resources alone does not explain increased FTR rates.
    JAMA SURGERY 01/2014; 149(3). DOI:10.1001/jamasurg.2013.3566 · 3.94 Impact Factor
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    ABSTRACT: Little is known about ghrelin's effects on intestinal epithelial cells even though it is known to be a mitogen for a variety of other cell types. Because ghrelin is released in close proximity to the proliferative compartment of the intestinal tract, we hypothesized that ghrelin may have potent pro-proliferative effect on intestinal epithelial cells as well. To test this hypothesis, we characterized the effects of ghrelin on FHs74Int and Caco-2 intestinal epithelial cell lines in vitro. We found that ghrelin has potent dose dependent proliferative effects in both cell lines through a yet to be characterized G protein coupled growth hormone secretagogue receptor (GHS-R) subtype. Consistent with above findings, cell cycle flowcytometric analyses demonstrated that ghrelin shifts cells from the G1 to S phase and thereby promotes cell cycle progression. Further characterization of subcellular events, suggested that ghrelin mediates its pro-proliferative effect through Adenylate cyclase (AC)-independent epidermal growth factor receptor (EGFR) trans-activation and PI3K-Akt phosphorylation. Both these pathways converge to stimulate MAPK, ERK 1/2 downstream. The role of ghrelin in states where intestinal mucosal injury and rapid mucosal repair occur warrants further investigation.
    Peptides 12/2013; 52. DOI:10.1016/j.peptides.2013.11.021 · 2.62 Impact Factor
  • Journal of the American College of Surgeons 09/2013; 217(3):S106. DOI:10.1016/j.jamcollsurg.2013.07.243 · 5.12 Impact Factor
  • Hina Y Bhutta · Stanley W Ashley
    Critical care medicine 08/2013; 41(8):2048-9. DOI:10.1097/CCM.0b013e31829133aa · 6.31 Impact Factor
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    ABSTRACT: IMPORTANCE There is a scarcity of research on immunocompromised patients with necrotizing soft-tissue infection (NSTI). OBJECTIVE To evaluate the effect of immunocompromised status in patients with NSTI. DESIGN AND SETTING Single-institution retrospective cohort study at a tertiary academic teaching hospital affiliated with a major cancer center. PARTICIPANTS Patients with NSTI. EXPOSURE Treatment at Brigham and Women's Hospital and Dana-Farber Cancer Institute between November 25, 1995, and April 25, 2011. MAIN OUTCOME AND MEASURE Necrotizing soft-tissue infection-associated in-hospital mortality. RESULTS Two hundred one patients were diagnosed as having NSTI. Forty-six were immunocompromised (as defined by corticosteroid use, active malignancy, receipt of chemotherapy or radiation therapy, diagnosis of human immunodeficiency virus or AIDS, or prior solid organ or bone marrow transplantation with receipt of chronic immunosuppression). At presentation, immunocompromised patients had lower systolic blood pressure (105 vs 112 mm Hg, P = .02), glucose level (124 vs 134 mg/dL, P = .03), and white blood cell count (6600/μL vs 17 200/μL, P < .001) compared with immunocompetent patients. Immunocompromised patients were less likely to have been transferred from another institution (26.1% vs 52.9%, P = .001), admitted to a surgical service (45.7% vs 83.2%, P < .001), or undergone surgical debridement on admission (4.3% vs 61.3%, P = .001). Time to diagnosis and time to first surgical procedure were delayed in immunocompromised patients (P < .001 and P = .001, respectively). Immunocompromised patients had higher NSTI-associated in-hospital mortality (39.1% vs 19.4%, P = .01). CONCLUSIONS AND RELEVANCE Immunocompromised status in patients with NSTI in this study is associated with delays in diagnosis and surgical treatment and with higher NSTI-associated in-hospital mortality. At presentation, immunocompromised patients may fail to exhibit typical clinical and laboratory signs of NSTI. Physicians caring for similar patient populations should maintain a heightened level of suspicion for NSTI and consider early surgical evaluation and treatment.
    JAMA SURGERY 05/2013; 148(5):419-26. DOI:10.1001/jamasurg.2013.173 · 3.94 Impact Factor
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    ABSTRACT: IMPORTANCE With duty hour debates, specialization, and sex distribution changes in the applicant pool, the relative competitiveness for general surgery residency (GSR) is undefined. OBJECTIVE To determine the modern attributes of top-ranked applicants to GSR. DESIGN Validation cohort, survey. SETTING National sample of university and community-based GSR programs. PARTICIPANTS Data were abstracted from Electronic Residency Application Service files of the top 20-ranked applicants to 22 GSR programs. We ranked program competitiveness and blinded review of personal statements. MAIN OUTCOMES AND MEASURES Characteristics associated with applicant ranking by the GSR program (top 5 vs 6-20) and ranking by highly competitive programs were identified using t and χ2 tests and modified Poisson regression. RESULTS There were 333 unique applicants among the 440 Electronic Residency Application Service files. Most applicants had research experience (93.0%) and publications (76.8%), and 28.4% had Alpha Omega Alpha membership. Nearly half were women (45.2%), with wide variation by program (20.0%-75.0%) and a trend toward fewer women at programs in the South and West (38.0% and 37.5%, respectively). Men had higher United States Medical Licensing Examination Step 1 scores (238.0 vs 230.1; P < .001) but similar Step 2 scores (245.3 vs 244.5; P = .54). Using bivariate analysis, highly competitive programs were more likely to rank applicants with publications, research experience, Alpha Omega Alpha membership, higher Step 1 scores, and excellent personal statements and those who were male or Asian. However, the only significant predictors were Step 1 scores (relative risk [RR], 1.36 for every 10-U increase), publications (RR, 2.20), personal statements (RR, 1.62), and Asian race (RR, 1.70 vs white). Alpha Omega Alpha membership (RR, 1.62) and Step 1 scores (RR, 1.01) were the only variables predictive of ranking in the top 5. CONCLUSIONS AND RELEVANCE This national sample shows GSR is a highly competitive, sex-neutral discipline in which academic performance is the most important factor for ranking, especially in the most competitive programs. This study will inform applicants and program directors about applicants to the GSR program.
    JAMA SURGERY 05/2013; 148(5):413-7. DOI:10.1001/jamasurg.2013.180 · 3.94 Impact Factor
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    ABSTRACT: Background: Intestinal absorptive capacity shows a circadian rhythm synchronized with eating patterns. Disrupting these coordinated rhythms, e.g., with shift work, may contribute to metabolic disease. Circadian expression of nutrient transporters has not been studied in metabolic disease. We studied the circadian rhythm of intestinal transporter sodium glucose co-transporter type 1 (SGLT1) in an obese diabetic rat. Methods: We compared obese Zucker diabetic fatty (ZDF) rats to lean ZDF littermates. Temporal feeding patterns were assessed, then rats were harvested at Zeitgeber (ZT, ZT0 = 7:00 a.m.) 3, 9, or 15 to measure insulin resistance, SGLT1 expression and intestinal glucose absorption capacity. Regulators of SGLT1 (sweet taste receptor T1R2/3; clock genes) were measured to elucidate underlying mechanisms. Results: Both groups exhibited altered circadian food intake. Obese ZDF rats lost circadian rhythmicity of SGLT1 mRNA expression and functional activity. Lean ZDF rats maintained rhythmicity of SGLT1 mRNA expression but that of functional glucose absorption was blunted. Circadian rhythms of intestinal clock genes were maintained in both groups. Neither group had discernible rhythms of intestinal GLUT2 (glucose transporter) or T1R2 (sweet taste receptor component) mRNA expression. In summary, lean and obese ZDF rats exhibited similar disruptions in circadian feeding. Glucose intolerance was evident in lean rats, but only obese rats further developed diabetes and exhibited disrupted circadian rhythmicity of both SGLT1 mRNA expression and function. Conclusions: Our findings suggest that disrupted circadian feeding rhythms contribute to glucose intolerance, but additional factors (genetics, changes in nutrient sensing/transport) are needed to lead to full diabetes.
    Digestive Diseases and Sciences 04/2013; 58(6). DOI:10.1007/s10620-013-2669-y · 2.61 Impact Factor
  • Emily Z Keung · Stanley W Ashley
    JAMA SURGERY 03/2013; 148(3):291. DOI:10.1001/jamasurg.2013.1025 · 3.94 Impact Factor
  • R.K. Sethi · A.J. Henry · E.M. Breen · S.W. Ashley · L.L. Nguyen
    Journal of Surgical Research 02/2013; 179(2):227. DOI:10.1016/j.jss.2012.10.414 · 1.94 Impact Factor
  • Journal of Surgical Education 11/2012; 69(6):687-92. DOI:10.1016/j.jsurg.2012.08.012 · 1.38 Impact Factor
  • Hina Y Bhutta · Stanley W Ashley
    Journal of Surgical Research 08/2012; 185(2). DOI:10.1016/j.jss.2012.08.009 · 1.94 Impact Factor
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    ABSTRACT: Practicing within the Halstedian model of surgical education, academic surgeons serve dual roles as physicians to their patients and educators of their trainees. Despite this significant responsibility, few surgeons receive formal training in educational theory to inform their practice. The goal of this work was to gain an understanding of how master surgeons approach teaching uncommon and highly complex operations and to determine the educational constructs that frame their teaching philosophies and approaches. Individuals included in the study were queried using electronically distributed open-ended, structured surveys. Responses to the surveys were analyzed and grouped using grounded theory and were examined for parallels to concepts of learning theory. Academic teaching hospital. Twenty-two individuals identified as master surgeons. Twenty-one (95.5%) individuals responded to the survey. Two primary thematic clusters were identified: global approach to teaching (90.5% of respondents) and approach to intraoperative teaching (76.2%). Many of the emergent themes paralleled principles of transfer learning theory outlined in the psychology and education literature. Key elements included: conferring graduated responsibility (57.1%), encouraging development of a mental set (47.6%), fostering or expecting deliberate practice (42.9%), deconstructing complex tasks (38.1%), vertical transfer of information (33.3%), and identifying general principles to structure knowledge (9.5%). Master surgeons employ many of the principles of learning theory when teaching uncommon and highly complex operations. The findings may hold significant implications for faculty development in surgical education.
    Journal of Surgical Education 07/2012; 69(4):493-8. DOI:10.1016/j.jsurg.2012.02.002 · 1.38 Impact Factor
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    Dimitrios Xourafas · Ali Ardestani · Stanley W Ashley · Ali Tavakkoli
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    ABSTRACT: Alanine aminotransferase (ALT) is used to detect non-alcoholic fatty liver disease and has been associated with increased risk of metabolic syndrome and type II diabetes mellitus (T2DM). Bariatric procedures result in significant weight loss and a rapid resolution of T2DM. We aimed to study the impact of bariatric interventions on ALT levels in patients with or without T2DM and compare this effect between different types of weight-loss procedures. We reviewed 756 patients undergoing bariatric surgery. Demographics, co-morbidities, baseline and post-operative ALT and HbA1C levels, weight-loss data, and diabetes status were recorded. ALT levels were compared between different procedures and between diabetic and non-diabetic patients. Chi-square test, ANOVA, and t test were used to evaluate outcomes. Males and diabetics had significantly higher ALT at baseline. Both Roux-en-Y gastric bypass surgery (RYGB) and laparoscopic adjustable gastric banding (LAGB) resulted in significant reduction in ALT levels beginning at the third post-operative month (20 and 17 %, respectively, compared to baseline, p < 0.001). ALT remained at the new low level up to year 3 after surgery. The degree of reduction was similar for both procedures and was independent of the degree of weight loss. In diabetics, ALT reduction was associated with improvement in disease; but in T2DM patients who remained on insulin, ALT remained elevated. RYGB and LAGB decrease ALT levels to the same degree and independent of weight loss. Our data confirm higher ALT in diabetics and demonstrate a rapid normalization after bariatric surgery with a simultaneous decrease in HbA1C. These results suggest that ALT may be used as a marker of metabolic improvement after bariatric surgery.
    Obesity Surgery 05/2012; 22(10):1540-7. DOI:10.1007/s11695-012-0677-1 · 3.75 Impact Factor

Publication Stats

6k Citations
1,323.80 Total Impact Points


  • 1998–2015
    • Harvard Medical School
      • Department of Surgery
      Boston, Massachusetts, United States
  • 2004–2014
    • Harvard University
      • Department of Health Policy and Management
      Cambridge, Massachusetts, United States
  • 1997–2014
    • Brigham and Women's Hospital
      • Department of Surgery
      Boston, Massachusetts, United States
  • 2009–2012
    • Beverly Hospital, Boston MA
      BVY, Massachusetts, United States
  • 2011
    • Cedars-Sinai Medical Center
      • Cedars Sinai Medical Center
      Los Ángeles, California, United States
  • 2007
    • University of Massachusetts Boston
      Boston, Massachusetts, United States
  • 2002
    • Vanderbilt University
      • Department of Surgery
      Нашвилл, Michigan, United States
  • 2001
    • Massachusetts General Hospital
      Boston, Massachusetts, United States
  • 1993–2000
    • University of California, Los Angeles
      • Department of Surgery
      Los Angeles, California, United States
  • 1992–1999
    • Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center
      Torrance, California, United States
  • 1995–1997
    • Harbor-UCLA Medical Center
      Torrance, California, United States
    • University of Cincinnati
      • Department of Surgery
      Cincinnati, Ohio, United States