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Dive into the research topics where Amy L. Halverson is active.

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Featured researches published by Amy L. Halverson.


Journal of The American College of Surgeons | 2013

Validation of new readmission data in the American College of Surgeons National Surgical Quality Improvement Program.

Morgan M. Sellers; Ryan P. Merkow; Amy L. Halverson; Keiki Hinami; Rachel R. Kelz; David J. Bentrem; Karl Y. Bilimoria

BACKGROUND Hospital readmissions are gathering increasing attention as a measure of health care quality and as a cost-saving target. The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) recently began collecting data related to 30-day postoperative readmissions. Our objectives were to assess the accuracy of the ACS NSQIP readmission variable by comparison with the medical record, and to evaluate the readmission variable against administrative data. STUDY DESIGN Readmission data captured in ACS NSQIP at a single academic institution between January and December 2011 were compared with data abstracted from the medical record and administrative data. RESULTS Of 1,748 cases captured in ACS NSQIP, 119 (6.8%) had an all-cause readmission event identified, and ACS NSQIP had very high agreement with chart review for identifying all-cause readmission events (κ = 0.98). For 1,110 inpatient cases successfully matched with administrative data, agreement with chart review for identifying all-cause readmissions was also very high (κ = 0.97). For identifying unplanned readmission events, ACS NSQIP had good agreement with chart review (κ = 0.67). Overall, agreement with chart review on cause of readmission was higher for ACS NSQIP (κ = 0.75) than for administrative data (κ = 0.46). CONCLUSIONS The ACS NSQIP accurately captured all-cause and unplanned readmission events and had good agreement with the medical record with respect to cause of readmission. Administrative data accurately captured all-cause readmissions, but could not identify unplanned readmissions and less consistently agreed with chart review on cause. The granularity of clinically collected data offers tremendous advantages for directing future quality efforts targeting surgical readmission.


Blood | 2010

Autologous nonmyeloablative hematopoietic stem cell transplantation in patients with severe anti-TNF refractory Crohn disease: long-term follow-up

Richard K. Burt; Robert M. Craig; Francesca Milanetti; Kathleen Quigley; Paula Gozdziak; Jurate Bucha; Alessandro Testori; Amy L. Halverson; Larissa Verda; Willem J. de Villiers; Borko Jovanovic; Yu Oyama

We evaluated the safety and clinical outcome of autologous nonmyeloablative hematopoietic stem cell transplantation (HSCT) in patients with severe Crohn disease (CD) defined as a Crohn Disease Activity Index (CDAI) greater than 250, and/or Crohn Severity Index greater than 16 despite anti-tumor necrosis factor therapy. Stem cells were mobilized from the peripheral blood using cyclophosphamide (2.0 g/m(2)) and G-CSF (10 μg/kg/day), enriched ex vivo by CD34(+) selection, and reinfused after immune suppressive conditioning with cyclophosphamide (200 mg/kg) and either equine antithymocyte globulin (ATG, 90 mg/kg) or rabbit ATG (6 mg/kg). Eighteen of 24 patients are 5 or more years after transplantation. All patients went into remission with a CDAI less than 150. The percentage of clinical relapse-free survival defined as the percent free of restarting CD medical therapy after transplantation is 91% at 1 year, 63% at 2 years, 57% at 3 years, 39% at 4 years, and 19% at 5 years. The percentage of patients in remission (CDAI < 150), steroid-free, or medication-free at any posttransplantation evaluation interval more than 5 years after transplantation has remained at or greater than 70%, 80%, and 60%, respectively. This trial was registered at www.clinicaltrials.gov as NCT0027853.


Proceedings of the National Academy of Sciences of the United States of America | 2010

In colorectal cancer mast cells contribute to systemic regulatory T-cell dysfunction.

Nichole R. Blatner; Andreas Bonertz; Eric C. Cheon; Seth B. Krantz; Matthew J. Strouch; Juergen Weitz; Moritz Koch; Amy L. Halverson; David J. Bentrem; Khashayarsha Khazaie

T-regulatory cells (Treg) and mast cells (MC) are abundant in colorectal cancer (CRC) tumors. Interaction between the two is known to promote immune suppression or loss of Treg functions and autoimmunity. Here, we demonstrate that in both human CRC and murine polyposis the outcome of this interaction is the generation of potently immune suppressive but proinflammatory Treg (ΔTreg). These Treg shut down IL10, gain potential to express IL17, and switch from suppressing to promoting MC expansion and degranulation. This change is also brought about by direct coculture of MC and Treg, or culture of Treg in medium containing IL6 and IL2. IL6 deficiency in the bone marrow of mice susceptible to polyposis eliminated IL17 production by the polyp infiltrating Treg, but did not significantly affect the growth of polyps or the generation of proinflammatory Treg. IL6-deficient MC could generate proinflammatory Treg. Thus, MC induce Treg to switch function and escalate inflammation in CRC without losing T-cell–suppressive properties. IL6 and IL17 are not needed in this process.


Science Translational Medicine | 2012

Expression of RORγt Marks a Pathogenic Regulatory T Cell Subset in Human Colon Cancer

Nichole R. Blatner; Mary F. Mulcahy; Kristen L. Dennis; Denise M. Scholtens; David J. Bentrem; Joseph D. Phillips; Soo Ham; Barry P. Sandall; Mohammad W. Khan; David M. Mahvi; Amy L. Halverson; Steven J. Stryker; Anne Marie Boller; Ashima Singal; Rebekka K. Sneed; Bara Sarraj; Mohammed Javeed Ansari; Martin Oft; Yoichiro Iwakura; Liang Zhou; Andreas Bonertz; Fotini Gounari; Khashayarsha Khazaie

Tregs that expand in human colon cancer have proinflammatory properties and contribute to tumor progression. A Treg Melting Pot Some things are not what they seem. Like the allegorical wolf in sheep’s clothing, cell populations that may seem homogeneous may actually contain subsets with different functions. Indeed, such hidden subpopulations may result in contradictory findings in different systems. Blatner et al. now find a subset of regulatory T cells (Tregs) in human colon cancer that may explain disparate clinical outcomes between studies. The authors found preferential expansion in human colon cancer of Tregs that can suppress T cells but are not anti-inflammatory like more classic Tregs. They then looked in a mouse model of hereditary polyposis and found that these cells, which express Foxp3 and RORγt, express the proinflammatory cytokine IL-17 and are directly associated with inflammation and disease progression. The balance between anti-inflammatory Tregs and these “pathogenic” proinflammatory Tregs may play a role in regulating cancer inflammation. Targeting these RORγt+ Tregs may influence disease outcome in colon cancer. The role of regulatory T cells (Tregs) in human colon cancer (CC) remains controversial: high densities of tumor-infiltrating Tregs can correlate with better or worse clinical outcomes depending on the study. In mouse models of cancer, Tregs have been reported to suppress inflammation and protect the host, suppress T cells and protect the tumor, or even have direct cancer-promoting attributes. These different effects may result from the presence of different Treg subsets. We report the preferential expansion of a Treg subset in human CC with potent T cell–suppressive, but compromised anti-inflammatory, properties; these cells are distinguished from Tregs present in healthy donors by their coexpression of Foxp3 and RORγt. Tregs with similar attributes were found to be expanded in mouse models of hereditary polyposis. Indeed, ablation of the RORγt gene in Foxp3+ cells in polyp-prone mice stabilized Treg anti-inflammatory functions, suppressed inflammation, improved polyp-specific immune surveillance, and severely attenuated polyposis. Ablation of interleukin-6 (IL-6), IL-23, IL-17, or tumor necrosis factor–α in polyp-prone mice reduced polyp number but not to the same extent as loss of RORγt. Surprisingly, loss of IL-17A had a dual effect: IL-17A–deficient mice had fewer polyps but continued to have RORγt+ Tregs and developed invasive cancer. Thus, we conclude that RORγt has a central role in determining the balance between protective and pathogenic Tregs in CC and that Treg subtype regulates inflammation, potency of immune surveillance, and severity of disease outcome.


Surgery | 2011

Communication failure in the operating room

Amy L. Halverson; Jessica T. Casey; Jennifer L. Andersson; Karen Anderson; Christine S. Park; Alfred Rademaker; Don W. Moorman

BACKGROUND Communication errors contribute to the occurrence of adverse events in various domains of health care. Recent studies surveying perceptions of communication in the operating room have found disparities in the perceived quality of communication among members of the operating room team. Our aim was to characterize the nature of communication failures observed in the operating room and to assess whether a Team Training curriculum had any impact on observed communication errors. METHODS Intraoperative observation was performed and communication errors were identified according to predetermined criteria. Observed errors were classified according to the type of error, subject matter, and observed effect. RESULTS Seventy-six communication failures were observed over 150 hours of observation. Overall, communication errors relating to equipment and keeping team members informed of the progress of an operation comprised 36% and 24% of all observed communication errors, respectively. Prior to the introduction of a Team Training curriculum, 56 errors were observed over 76 hours (rate,737 errors per hour; standard error, 0.098). After Team Training, 20 errors over 74 hours were observed (rate .270 errors per hour; standard error, 0.060; P < .001). CONCLUSION Communication failures related most frequently to equipment and keeping team members updated as to the progress of an operation. These failures can lead to procedural delay and inefficiencies. A program that teaches teamwork and communication skills is one strategy that may improve communication among members of the operating room team.


Journal of The National Comprehensive Cancer Network | 2010

Colorectal Cancer Screening

Randall W. Burt; Jamie A. Cannon; Donald David; Dayna S. Early; James M. Ford; Francis M. Giardiello; Amy L. Halverson; Stanley R. Hamilton; Heather Hampel; Mohammad K. Ismail; Kory Jasperson; Jason B. Klapman; Audrey J. Lazenby; Patrick M. Lynch; Robert J. Mayer; Reid M. Ness; Dawn Provenzale; M. Sambasiva Rao; Moshe Shike; Gideon Steinbach; Jonathan P. Terdiman; David S. Weinberg; Mary A. Dwyer; Deborah A. Freedman-Cass

During the past decade we have seen dramatic advances in colon cancer screening. Reduction in mortality in average risk screening for colorectal cancer has now been shown in multiple trials. Efforts to increase public awareness and compliance with evidence-based screening guidelines are underway. Recent guidelines have incorporated family history, as it has been identified as a common risk factor. The genes responsible for the inherited syndromes of colon cancer have been identified and genetic testing is available. Currently, screening the average risk population over the age of 50 would reduce mortality from colon cancer by 50%. Future advances will likely include improved screening tests, and the development of familial genetic testing.


Diseases of The Colon & Rectum | 2009

Outcomes and Prognostic Factors for Squamous-Cell Carcinoma of the Anal Canal : Analysis of Patients From the National Cancer Data Base

Karl Y. Bilimoria; David J. Bentrem; Colin E. Rock; Andrew K. Stewart; Clifford Y. Ko; Amy L. Halverson

PURPOSE: The objective of this study was to assess survival and prognostic factors for anal carcinoma in the population. METHODS: Patients with squamous-cell carcinoma of the anal canal were identified from the National Cancer Data Base (1985-2000). Univariate and multivariable methods were used to assess factors associated with survival. Concordance was calculated to assess agreement between American Joint Committee on Cancer stage and actual outcome. RESULTS: Nineteen thousand one hundred ninety-nine patients with anal carcinoma were identified (Stage I, 25.3 percent; Stage II, 51.8 percent; Stage III, 17.1 percent; Stage IV, 5.7 percent). Overall five-year survival was 58.0 percent. The American Joint Committee on Cancer (6th edition) staging system provided good survival discrimination by stage: I, 69.5 percent; II, 59.0 percent; III, 40.6 percent; and IV, 18.7 percent (concordance index, 0.663). On multivariable analysis, patients with anal carcinoma had a higher risk of death if they were male, ≥65 years old, black, living in lower median incomes areas, and had more advanced T stage tumors, nodal or distant metastases, or poorly differentiated cancers (P < 0.0001). There was not a significant difference in survival by hospital type or year of diagnosis. CONCLUSION: Although tumor characteristics and staging affect prognosis, patient factors, such as gender, race, and socioeconomic status, are also important prognostic factors for squamous-cell carcinoma of the anal canal.


Diseases of The Colon & Rectum | 2009

Ten-year outcome after anal sphincter repair for fecal incontinence.

Massarat Zutshi; Tracy L. Hull; Jane Bast; Amy L. Halverson; Jeanie Na

PURPOSE: This study aimed to report at ten years on the results of the same cohort that had been studied at five years who had undergone an anal sphincter repair for fecal incontinence. METHODS: Patients studied at five years were contacted after ten years and asked to fill out the Fecal Incontinence Quality of Life Scale, the Fecal Incontinence Severity Index, and the Bristol Stool Form Scale. RESULTS: Thirty-one of 44 (71 percent) patients were contacted. Median follow-up time was 129 (range, 113 to 208) months. Median age at surgery was 44 (range, 22 to 80) years. No patients were fully continent at 129 months. Fecal Incontinence Severity Index and Fecal Incontinence Quality of Life scores were correlated with the age at surgery. Older patients had lower Fecal Incontinence Quality of Life scores (P = 0.001), reflecting a lower quality of life, and a higher patient-rated Fecal Incontinence Severity Index score (P = 0.01) and a higher surgeon-rated Fecal Incontinence Severity Index score (P = 0.005), denoting more severe fecal incontinence. The Bristol Stool Form Scale, not utilized at 77 months, showed a correlation to patient-rated Fecal Incontinence Severity Index (P = 0.04) and surgeon-rated Fecal Incontinence Severity Index (P = 0.02). Fecal Incontinence Severity Index scores were significantly higher in women who had more than two vaginal births. CONCLUSION: Continence after overlapping sphincter repair deteriorates in the long term. Long-term outcome was worse for patients who were older at the time of surgery or those with two or more vaginal births. The Bristol Stool Form Scale score correlates with the severity of incontinence, and may be used to guide the management of the patients symptoms.


Archives of Surgery | 2009

Surgical Team Training The Northwestern Memorial Hospital Experience

Amy L. Halverson; Jennifer L. Andersson; Karen Anderson; Justin Lombardo; Christine S. Park; Alfred Rademaker; Don W. Moorman

OBJECTIVES To develop and implement a team-training curriculum. We hypothesized that better interactions between personnel would lead to improved patient safety, increased efficiency, and better staff satisfaction. DESIGN Prospective assessment of a team-training program. SETTING University-affiliated hospital. PARTICIPANTS Operating room physicians, nurses, technicians, and other personnel. INTERVENTIONS Four-hour classroom curriculum, intraoperative coaching on team-related behaviors, and follow-up feedback sessions. MAIN OUTCOME MEASURES Baseline metrics and observational data were collected for 3 months before implementing the team-training program and 6 months after a designated implementation date. A questionnaire regarding perceptions of teamwork was completed at the beginning of and 6 weeks following the team-training classroom session. RESULTS Six months after implementation of team training, compliance with preoperative briefings was 66%. No changes in hospital metrics were observed. An improved perception of teamwork among the participants was demonstrated in pretraining and posttraining surveys. Perceptions of teamwork and the utility of a preoperative briefing differed among nurses, surgeons, and anesthesiologists. CONCLUSIONS Our team-training program resulted in moderate compliance with behaviors taught in the curriculum. Even with only moderate compliance, we demonstrated improved perceptions of teamwork.


Diseases of The Colon & Rectum | 2014

Systematic review of internet patient information on colorectal cancer surgery

Molly A. Wasserman; Nancy N. Baxter; B. Rosen; Marcus Burnstein; Amy L. Halverson

BACKGROUND: Patients diagnosed with colorectal cancer often seek information on the Internet to help them make treatment decisions. OBJECTIVE: The aim of this study is to evaluate the quality of Web-based patient information regarding surgery for colorectal cancer. DESIGN: This study is a cross-sectional survey of patient-directed Web sites. SETTINGS: The search engine Google (Mountain View, CA) and the search terms “colorectal cancer surgery,” “colon cancer surgery,” and “rectal cancer surgery” were used to identify Web sites. MAIN OUTCOME MEASURES: To assess quality, we used the DISCERN instrument, a validated questionnaire developed to analyze written consumer health information on treatment options to aid consumers in evaluating the quality of health-related information on treatment choices for a specific health problem. An additional colorectal cancer-specific questionnaire was used to evaluate Web site content for colorectal cancer surgical treatment. Two independent assessors reviewed each Web site. RESULTS: Searches revealed a total of 91 distinct Web sites, of which 37 met inclusion criteria. Web site affiliation was as follows: 32% open-access general information, 24% hospital/health care organization, and 19% professional medical society. Twelve (32.4%) Web sites had clear aims, 10 (27.0%) had identifiable references to their sources of information, and 9 (24.3%) noted the date of published information. Ten sites (27.0%) provided some description of the surgical procedure, 8 (21.6%) discussed either the risks or the benefits of surgery, and 4 (10.8%) addressed quality-of-life issues. Nineteen (51.4%) Web sites discussed postoperative complications, and 7 (18.9%) discussed stoma-related maintenance/care. LIMITATIONS: The small sample size and interrater reliability bias are limitations of this study. CONCLUSIONS: The quality of online patient information regarding colorectal cancer treatment is highly variable, often incomplete, and does not adequately convey the information necessary for patients to make well-informed medical decisions regarding treatment for colorectal cancer. An opportunity exists for professional medical societies to create more comprehensive online patient information materials that may serve as a resource to physicians and their patients (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A122).

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Patrick M. Lynch

University of Texas MD Anderson Cancer Center

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Robert J. Mayer

University of Texas MD Anderson Cancer Center

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Stanley R. Hamilton

University of Texas MD Anderson Cancer Center

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Audrey J. Lazenby

University of Nebraska Medical Center

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Moshe Shike

Memorial Sloan Kettering Cancer Center

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