Neil Hyman

University of Vermont, Burlington, VT, United States

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Publications (137)778.3 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: A large proportion of patients with a colostomy or an ileostomy develop parastomal hernias. The placement of a reinforcing material at the stoma site may reduce parastomal hernia incidence. We aimed to assess the safety and efficacy of stoma reinforcement with sublay placement of non-cross-linked porcine-derived acellular dermal matrix at the time of stoma construction. This is a randomized, patient- and third-party assessor-blind, controlled trial. This study took place in colorectal/general surgery institutions. Patients were prospectively randomly assigned to undergo standard end-stoma construction with or without porcine-derived acellular dermal matrix reinforcement. Patients undergoing construction of a permanent stoma were eligible. A total of 113 patients (59 men, 54 women; mean age, 60 years; mean BMI, 25.4 kg/m) participated: 58 controls and 55 with reinforcement. The incidence of parastomal hernia, safety, and stoma-related quality of life were assessed. Intraoperative complications and blood loss were similar between groups. Quality-of-life scores were similar through 24 months of follow-up. At 24 months of follow-up, the incidence of parastomal hernias was similar for both groups (12.2% of the porcine-derived acellular dermal matrix group and 13.2% of controls). Study limitations include the inclusion of ileostomy and colostomy patients, open and laparoscopic techniques, and small numbers of patients at follow-up. Safety and quality-of-life data from this randomized control trial show similar outcomes in both groups. Prosthetic reinforcement of stomas was safe, but it did not significantly reduce the incidence of parastomal hernia formation. Identification no. NCT00771407.
    Diseases of the Colon & Rectum 05/2014; 57(5):623-31. · 3.34 Impact Factor
  • Larson Erb, Neil H. Hyman, Turner Osler
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    ABSTRACT: Background Anastomotic leak is a serious complication of gastrointestinal surgery. Abnormal vital signs are often cited in retrospective peer review and medicolegal settings as evidence of negligence in the failure to make an early diagnosis. We aimed to profile the postoperative course of patients who undergo intestinal anastomosis and determine how reliably abnormal vital signs predict anastomotic leaks. Study Design Consecutive patients undergoing bowel resection with anastomosis at an academic medical center between July 2009 through July 2011 were identified from a prospective complication database. The electronic medical record was queried for postoperative vital signs and laboratory studies which were digitally abstracted. Abnormal values were defined as temperature >38°C, white blood cell count ≤4000 or ≥12,000 cells/uL, systolic blood pressure ≤80 mmHg or diastolic blood pressure ≤50 mmHg, pulse ≥100 beats per minute and respiratory rate ≥20 breaths per minute. Patients who developed an anastomotic leak were compared to those with an uncomplicated postoperative course. Results Of the 452 patients, 141 (31.2%) suffered a total of 271 complications, including 19 anastomotic leaks. Even in “uncomplicated” recoveries, tachycardia and tachypnea were almost routine, occurring in more than half of the patients frequently throughout the postoperative period. Hypotension, fever and leukocytosis were also remarkably common. The positive predictive value of any aberrant vital sign or white blood cell count ranged between 4-11%. Conclusions Abnormal vital signs are extremely common after bowel resection with anastomosis. Even sustained aberrant vital signs and/or leukocytosis is not necessarily suggestive of a leak or other postoperative complication.
    Journal of the American College of Surgeons 01/2014; · 4.50 Impact Factor
  • Source
    Mohammad S. Jafferji, Neil Hyman
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    ABSTRACT: Background The “best’ operation in the setting of acute complicated diverticulitis has been debated for decades. Multiple studies, including a recent prospective randomized trial, have reported improved outcomes with primary anastomosis. The aim of this study was to determine whether surgeon or patient specific factors drive the choice of operative procedure. Study Design Consecutive adult patients with sigmoid diverticulitis requiring emergent operative treatment for acute complicated diverticulitis from 1997-2012 at an academic medical center were identified from a prospectively maintained complications database. Patient characteristics, surgeon, choice of operation and outcomes including postoperative complications and stoma reversal were noted. The use of primary anastomosis and associated outcomes between colorectal and noncolorectal surgeons were compared. Results 151 patients underwent urgent resection during the study period and 136 met inclusion criteria. 82 resections (65.1%) were performed by noncolorectal surgeons and 44 by colorectal surgeons (34.9%). Noncolorectal surgeons performed more HP (68.3% vs 40.9%, p=0.01) despite similar demographics, ASA classification and Hinchey stage. Length of stay, time to stoma reversal, ICU days and postop complications were lower in the colorectal group (43.2% vs 16.7, p=0.02). Conclusions Although patient specific factors are important, surgeon is a potent predictor of operation performed in the setting of severe acute diverticulitis. A more aggressive approach to primary anastomosis may lower the complication rate after surgical treatment for severe acute diverticulitis.
    Journal of the American College of Surgeons 01/2014; · 4.50 Impact Factor
  • Article: Mentorship.
    Joseph Platz, Neil Hyman
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    ABSTRACT: The world of medicine is in a state of flux with major and substantive changes in its educational model. Students, residents, and junior attendings can no longer rely entirely on experiential development through clinical immersion. Instead, to attain similar levels of knowledge, technique, and situational comfort, there must be innovations in medical education that take advantage of the experience of mentors. Mentoring has been a part of medicine and surgery since the days of apprenticeship. Mentors must now teach more basic medicine than ever before and adapt to changes in the structure of medical education such as the use of simulation, yet still continue to foster career development among trainees and junior colleagues. For mentoring to succeed and benefit mentees, it must be supported. This patronage starts with each local university or hospital system but eventually must permeate the greater medical culture.
    Clinics in Colon and Rectal Surgery 12/2013; 26(4):218-223.
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    ABSTRACT: Background: Patients with Crohn's disease typically undergo computed tomography (CT) scans periodically over the course of their chronic disorder, requiring only modest doses of ionizing radiation. However, previous studies have suggested there is a subgroup of patients with Crohn's disease who undergo frequent CT scans with an associated increase in health care expenditures and possible overexposure to radiation, potentially placing such patients at increased risk for cancer. The aim of our study was to characterize and define this potentially vulnerable cohort using a relatively homogeneous surgical population. Methods: Consecutive patients who underwent ileocolic resection for Crohn's disease from January 2000 to September 2010 at an academic medical center were identified from a prospectively maintained database. Only patient CT scans remote from surgery or hospitalization were considered in the analysis. The number of outpatient CT scans, physician visits, and coexisting psychiatric and functional diagnoses were recorded from retrospective chart review. Patients who were considered high CT scan utilizers were compared with patients who were low utilizers. Results: Sixty-three patients underwent 126 CT scans during the study period, however, 4 of the patients accounted for 52 (41%) of the studies. Compared with the overall study population, the subset of 4 patients (high utilizers) had a median of 66 clinic visits (P < 0.001) and 40 emergency department visits (P < 0.001). All 4 patients were on chronic narcotic medication, and only 1 did not have a concomitant functional disorder. Missed appointments and the absence of prescribed antidepressants were common among patients with high CT use. Conclusions: Although use of CT appears moderate in surgical patients with Crohn's disease overall, there is a subset of patients with chronic pain and psychiatric diagnoses, who frequently miss appointments, and account for a markedly disproportionate number of scans performed. Interestingly, use of antidepressants in patients with Crohn's disease was strongly associated with fewer scans, suggesting an opportunity for therapeutic intervention.
    Postgraduate Medicine 11/2013; 125(6):94-9. · 1.97 Impact Factor
  • Ari Garber, Neil Hyman, Turner Osler
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    ABSTRACT: Primary anastomosis with or without proximal diversion is increasingly applied to patients requiring urgent colectomy for complicated disease of the left colon. As such, the Hartmann procedure is now often restricted to patients who are unstable or otherwise poor candidates for primary anastomosis. We sought to define the complication rate of Hartmann takedown in a contemporary setting. Consecutive adult patients undergoing colostomy takedown with colorectal anastomosis at an academic teaching hospital from January 1, 2001, to December 31, 2010, were included in the study. Complications were captured prospectively by a single trained nurse practitioner. Demographics, body mass index, American Society of Anesthesiologists (ASA) classification, interval between Hartmann procedure and subsequent takedown, surgical indication, duration of surgery, surgeon volume and specialty, length of stay, and complications were recorded. One hundred three patients underwent Hartmann reversal by 16 different surgeons; 7 of these surgeons performed 4 or fewer procedures during the study period. During the same time period, 334 patients underwent a Hartmann procedure at our institution. Seventy-seven of 104 patients (74%) had their index resection for complicated diverticulitis; an anastomotic leak was the second most common indication. The median age was 61 years (range 31 to 84 years), and the interval from Hartmann procedure to reversal ranged from 87 to 1,489 days. Only 8 patients (7.7%) had an ASA of 1. Thirty patients (29.1%) had postoperative complications, and 12 (11%) had 2 or more complications. There were 2 deaths and 4 anastomotic leaks, and 7 patients had inadvertent enterotomies. Only ASA status predicted postoperative complications (P = .01). Hartmann takedown is a morbid operation with a substantial risk of inadvertent enterotomy and serious complications. Excluding cases referred from elsewhere, there were more than 5-fold the number of Hartmann procedures than takedowns performed during the study period. This suggests that Hartmann procedures are typically restricted to patients who are also poor candidates for takedown and that their colostomy is likely to be permanent.
    American journal of surgery 09/2013; · 2.36 Impact Factor
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    ABSTRACT: Stage-specific survival for colon cancer improves when more lymph nodes are reported in the surgical specimen. This has led to a minimum standard of identifying 12 lymph nodes as a quality indicator. The aim of this study was to determine whether the addition of Schwartz solution increases node yield and impacts pathologic staging. This is a prospective cohort study. The study was conducted in an academic medical center. Included were 104 consecutive patients with colorectal cancer. Lymph node counts before and after specimen treatment with Schwartz solution and incidence of upstaging were measured. An additional 20 minutes (interquartile range, 15-40 minutes) was spent searching for lymph nodes, increasing the median number of nodes from 22.5 to 29.0 nodes. However, only 1 patient was upstaged. Schwartz solution decreased the number of specimens with less than 12 lymph nodes from 15 to 6. The following factors were associated with Schwartz solution leading to the detection of additional nodes: number of nodes detected initially with formalin only (p < 0.000), mesenteric fat volume (p < 0.000), mesenteric fat weight (p < 0.000), length of specimen (p < 0.016), tumor greatest dimension (p < 0.016), patient body surface area (p < 0.034), and patient age (p < 0.003). Clinical data for this study were obtained retrospectively and were not available for all of the patients. Although Schwartz solution increased the number of nodes detected in 95% of patients and improved compliance with the 12-node standard for colon resection, there was minimal impact on cancer staging. Upstaging is unlikely to explain the increase in overall survival in patients with higher lymph node counts, casting doubt on the validity of this process measure as a meaningful quality indicator. Rather, the lymph node count may be a reflection of inherent tumor biology or host-related factors.
    Diseases of the Colon & Rectum 09/2013; 56(9):1028-35. · 3.34 Impact Factor
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    ABSTRACT: AIM: Reservoir ileitis (pouchitis) is the most common complication after pelvic pouch surgery for ulcerative colitis and the aetiology remains largely unknown. The anal transition zone contains the only remaining colonic epithelium after ileal pouch-anal anastomosis and may provide important clues as to whether ulcerative colitis and pouchitis share a common pathogenesis. The aim of this study was to evaluate longitudinally the long term histologic changes in the anal transition zone and its relationship to the incidence of pouchitis. METHOD: Patients with a double-stapled ileal pouch anal anastomosis for ulcerative colitis at an academic medical centre with at least 10 years of clinical and histologic followup were identified from a prospective database. Annual anal transition zone (ATZ) and pouch biopsies were taken and interpreted by two expert GI pathologists. Anal transition zone histologic variability score, the incidence of pouchitis, and function were correlated over time. ATZ biopsies were scored from one to three based on the extent of inflammation. Results Sixteen of the 114 patients having IPAA fulfilled the ctiteria criteria for admission to the study.There were 179 biopsies of the ATZ. All exhbitedexhibited variability in ATZ histology over time and 81% had a 2 unit change in their inflammatory score. There was no correlation between pouchitis and histologic severity score of the ATZ. Similarly, function over time did not vary with the intensity of ATZ inflammation. CONCLUSION: ATZ inflammation varies substantially over time in most patients. But these changes from year to year did not correlate with function or the occurrence of pouchitis. This article is protected by copyright. All rights reserved.
    Colorectal Disease 06/2013; · 2.08 Impact Factor
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    ABSTRACT: BACKGROUND: Multimodality fast-track protocols have been shown to enhance recovery after bowel resection. However, it remains unclear which of the components impact outcomes and whether processes actually occur as intended. METHODS: Consecutive patients who underwent elective bowel resection at a university teaching hospital under a standardized fast-track recovery protocol were compared with patients who underwent similar procedures before protocol initiation. Compliance was measured with the 7 major elements of the protocol: administration of nonopioid analgesia, perioperative lidocaine, nasogastric tube removal, early feeding, early ambulation, and fluid restriction. RESULTS: Eighty pathway patients were compared with 87 conventional patients. Only 3 of the 7 major components were successfully implemented. Fluid restriction was achieved in only 2 patients. Pain scores and ileus-related morbidities were comparable with the exception of nasogastric tube reinsertion, which was required twice as often in pathway patients (17 vs 8, P = .02). Thirteen pathway patients were readmitted compared with 7 control patients (P = .11). CONCLUSIONS: The delivery of expected care cannot be assumed. There was no discernible benefit in patient outcomes.
    American journal of surgery 06/2013; · 2.36 Impact Factor
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    ABSTRACT: BACKGROUND: Computed tomography (CT) scans often identify postoperative fluid collections of uncertain clinical relevance. METHODS: Consecutive adult patients undergoing colorectal resection and postoperative CT scan from January 1, 2000 to December 31, 2008, at a university teaching hospital were identified from a prospective database. A host of clinical and CT findings were recorded. Fisher's exact test and logistic regression with univariate and multivariate analysis were used to assess the predictive value of clinical and radiologic variables. RESULTS: Nine hundred six patients had a colon resection during the study period. Fifty-four patients had a postoperative fluid collection, of which 36 were found to be abscesses. Only high clinical suspicion of an abscess predicted the presence of an abscess (P = .009); of the radiologic criteria, only proximity to the anastomosis was predictive (P = .05). CONCLUSIONS: Clinical judgment is superior to radiologic and individual clinical parameters. This finding has the potential to prevent many unnecessary procedures.
    American journal of surgery 06/2013; · 2.36 Impact Factor
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    ABSTRACT: IMPORTANCE Total proctocolectomy with ileal pouch-anal anastomosis is considered the procedure of choice for patients requiring elective surgery for ulcerative colitis, but some patients undergoing subtotal colectomy with end ileostomy are satisfied with an ileostomy and do not choose to undergo later pelvic pouch surgery. The need and timing for completion proctectomy in this setting are uncertain. OBJECTIVE To assess the long-term fate of the retained rectum compared with the morbidity associated with completion proctectomy in patients who underwent subtotal colectomy for ulcerative colitis. DESIGN AND SETTING Retrospective review of a prospective database in an academic medical center. PARTICIPANTS Patients who underwent subtotal colectomy with ileostomy for ulcerative colitis from July 1, 1990, to December 31, 2010. MAIN OUTCOMES AND MEASURES Proctectomy, surgical complications, and symptoms from the retained rectum. RESULTS One hundred eight patients underwent subtotal colectomy for ulcerative colitis during the study period: 73 for acute disease, 18 for advanced age and/or comorbidities, and 17 to avoid the risk of sexual dysfunction or infertility. Of these patients, 71 (65.7%) underwent subsequent ileal pouch-anal anastomosis, 2 died of other causes, and 3 were lost to follow-up. Of the remaining 32 patients, 20 chose rectal stump surveillance and 12 underwent elective proctectomy. Median follow-up was 13.8 years. No difference was noted in age, sex, surgical complications, pad use, or urinary dysfunction between the 2 groups. Only 8 of 20 patients in the surveillance group were compliant with follow-up endoscopy, and 13 were able to maintain their rectum; 2 required proctectomy at 11 and 16 years, respectively, for rectal cancer; neither has developed recurrent disease. One patient in each group reported erectile dysfunction. CONCLUSIONS AND RELEVANCE Management of the retained rectum after subtotal colectomy remains an important issue even in the era of ileal pouch-anal anastomosis. Considering the risk of rectal cancer, the low success rate of long-term rectal preservation, and the safety of surgery, a more aggressive approach to early completion proctectomy seems justified in this situation.
    JAMA surgery. 05/2013; 148(5):408-11.
  • Kevin Kuruvilla, Turner Osler, Neil H Hyman
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    ABSTRACT: : Total proctocolectomy with IPAA is frequently considered the procedure of choice for surgical patients with ulcerative colitis, presumably owing to an expectation of improved quality of life in comparison with an ileostomy. : The goal of our study was to determine whether long-term quality of life among patients with a pelvic pouch is better than those who chose a permanent stoma. : This investigation is a cross-sectional observational study using a prospective database. : This study was conducted at an academic medical center. : Consecutive patients who had undergone IPAA or a permanent ileostomy for ulcerative colitis by a single surgeon, presenting for their annual follow-up visit from July through September 2011, were offered participation in the study. A randomly chosen group of subjects who did not have scheduled appointments during the study period were sent a letter inviting them to participate in the study. : The primary outcome measures used were EQ-5D-3L, the Short Quality of Life in Inflammatory Bowel Disease questionnaire, the Cleveland Global Quality of Life instrument, the Fecal Incontinence Quality of Life scale, and the Stoma Quality of Life scale. : Thirty-five patients with a pelvic pouch and 24 ostomates were accrued and comprehensively studied. Global quality-of-life scores were virtually identical for the 2 groups. Patients with a pelvic pouch had better subscores in current quality of health and energy level, Fazio score, sexuality/body image, and work/social function. : This study was limited by its small sample size, and some of our patients were enrolled through mailed surveys and, hence, nonresponse bias may be present. The follow-up time since surgery was longer in the pelvic pouch group than in the ileostomy group. : Informed patients with ulcerative colitis choosing an ileostomy have a health-related global quality of life very similar to patients with a pelvic pouch. Better outcomes in patients with an ileal pouch were most evident in the areas of sexuality/body image and work/social function.
    Diseases of the Colon & Rectum 11/2012; 55(11):1131-7. · 3.34 Impact Factor
  • Joseph Platz, Neil Hyman
    Gastroenterology and Hepatology 10/2012; 8(10):700-702.
  • Joseph Platz, Neil Hyman
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    ABSTRACT: Relatively little is known or understood about the nature of complications that occur during a surgical procedure. Definitions, classification, and documentation are substantive challenges to comprehensive event capture. We hypothesized that our prospective complication database (ie, Surgical Activity Tracking System) would supplement traditional sources of intraoperative complication reporting. Consecutive patients undergoing surgery on a single general surgical service from June 2005 through May 2010 were selected for analysis. All cases had been entered into the Surgical Activity Tracking System, a prospective complication database that identifies and captures complications in real time, using a specially trained nurse practitioner. Intraoperative complications were grouped into 1 of 9 categories. Operative reports and discharge summaries were analyzed by an independent reviewer to determine if the complication(s) had been documented by a traditional data source. Eight thousand eight hundred and ninety-six operations were performed on 7,729 patients during the study period. One hundred and thirty-seven patients (1.5%) experienced an intraoperative complication. Nonintestinal organ lacerations, inadvertent enterotomies, and hemorrhage were the most common adverse events. The operative reports failed to mention 20 of the 151 complications (13%), and discharge summaries failed to report 22 complications (14%). Some complications, such as inadvertent enterotomy, were almost always reported, but others such as arrhythmia, were only occasionally described (25%). Our prospective complication tracking system identified a considerable number of complications that were not available in either the operative report or discharge summary. The number of unreported adverse events varied greatly by category, suggesting opportunities for improvement in both complication identification and tracking.
    Journal of the American College of Surgeons 06/2012; 215(4):519-23. · 4.50 Impact Factor
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    ABSTRACT: Angiogenesis is central to wound healing and tumor growth. Postoperative (postop) plasma from weeks 2 and 3 after minimally invasive colorectal resection (MICR) stimulates endothelial cell (EC) migration (MIG), invasion (INV), and proliferation (all vital to angiogenesis) compared with preoperative (preop) plasma results and may promote postop tumor growth. The purpose of this study was to determine whether plasma from open colorectal resection (OCR) patients has similar proangiogenic EC effects in vitro. OCR cancer patient plasma from institutional review board-approved banks was used; patients with preop and one postop sample from postoperative days (POD) 7-33 were eligible. Samples were bundled into 7- to 13-day periods and considered as single time points. In vitro cultures of human umbilical venous ECs were used for the EC proliferation (BPF, Branch Point Formation), INV, and MIG assays performed with preop, POD 7-13, POD 14-20, and POD 21-33 plasma. Data were analyzed by paired t test and were reported as mean ± standard deviation (significance, P < 0.05). Plasma from 53 cancer patients (25 rectal and 28 colon) was used. Because of limited postop samples, the number for each time point varies: POD 7-13, n = 30; POD 14-20, n = 26; and POD 21-33, n = 17. In vitro EC BPF was significantly greater at the POD 7-13 (P < 0.0001) and POD 14-20 (P < 0.0001) time points versus preop results. Significantly greater EC INV and MIG were noted on POD 7-13 and POD 14-20 versus the preop plasma results (P < 0.0001). In regards to POD 21-33, a significantly greater result was noted only for the INV assay versus preop. Plasma from weeks 2 and 3 after OCR stimulates in vitro EC BPF, INV, and MIG. A significant difference from preop baseline was noted only for the INV assay in week 4. The OCR and previous MICR results were largely similar. Tumor angiogenesis may be stimulated after OCR and MICR for 3 weeks. Further studies are warranted.
    Surgical Endoscopy 11/2011; 26(3):790-5. · 3.43 Impact Factor
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    ABSTRACT: Surgical site infections are a major source of expense and morbidity after colon resection. This study aimed to assess the effect of a targeted intervention to improve compliance with Surgical Care Improvement Project measures on the incidence of surgical site infection. A cohort of patients was prospectively monitored. The investigation was conducted at a university teaching hospital. Consecutive patients underwent open colon resection with anastomosis. A multidisciplinary committee consisting of a surgeon, anesthesiologist, nurses, and quality specialists was convened in late 2004 and a series of initiatives were designed, implemented, and tracked to improve performance on the 4 infection-related components of the Surgical Care Improvement Project program. Compliance with the 4 Surgical Care Improvement Project process measures and the rate of surgical site infection were documented. There was no improvement in the use of appropriate antibiotics (P = .66), administration within 1 hour of incision (P = .11), cessation within 24 hours (P = .36), or achievement of normothermia (P = .46). Similarly, there was no effect whatsoever on the incidence of surgical site infection over the study period (P = .84). The single-institution nature of the study limited its usefulness. A 5-year multidisciplinary program of targeted initiatives and interventions failed to improve compliance with Surgical Care Improvement Project measures or to decrease surgical site infection at our institution where colon resections are performed almost exclusively by high-volume specialists. These efforts consumed considerable resources and expenditures, but were of little or no value in our setting.
    Diseases of the Colon & Rectum 04/2011; 54(4):394-400. · 3.34 Impact Factor
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    ABSTRACT: Angiostatin and endostatin are endogenous inhibitors of angiogenesis with anticancer effects. After minimally invasive colorectal resection (MICR), blood levels of the proangiogenic factors vascular endothelial growth factor (VEGF) and angiopoetin 2 (Ang-2) are elevated for 2-4 weeks. Also, postoperative human plasma from weeks 2 and 3 after MICR has been shown to stimulate endothelial cell proliferation and migration, which are critical to angiogenesis. This proangiogenic state may stimulate tumor growth early after MICR. Surgery's impact on angiostatin and endostatin is unknown. This study's purpose is to determine perioperative plasma levels of these two proteins in colorectal cancer (CRC) patients undergoing MICR. Endostatin levels were assessed in 34 CRC patients and angiostatin levels in 30 CRC patients. Blood samples were taken preoperatively and on postoperative day (POD) 1 and 3 in all patients; in a subset, samples were taken between POD 7 and 20. The late samples were bundled into 7-day blocks (POD 7-13, POD 14-20) and considered as single time points. Angiostatin and endostatin plasma levels were determined via enzyme-linked immunosorbent assay (ELISA) in duplicate. Wilcoxon signed-rank test and Student's t test were used to analyze endostatin and angiostatin data, respectively. Significance was set at P<0.0125 (after Bonferroni correction). There was a significant decrease in median plasma endostatin levels on POD 1, which returned to the preoperative level by POD 3. There was no significant difference between pre- and postoperative plasma angiostatin levels. MICR has a very transient impact on plasma levels of endostatin and no impact on angiostatin during the first 21 days following surgery. Thus, angiostatin and endostatin do not likely contribute to or inhibit the persistent proangiogenic changes noted after MICR.
    Surgical Endoscopy 12/2010; 25(6):1939-44. · 3.43 Impact Factor
  • N Hyman
    British Journal of Surgery 11/2010; 97(11):1741. · 4.84 Impact Factor
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    ABSTRACT: Profiling of hospitals using risk-adjusted mortality rates as a measure of quality is becoming increasingly frequent. We sought to determine the validity of this approach by comparing the risk-adjusted predicted mortality to the findings of concurrent peer review and retrospective chart review of deaths that occur on a general surgery service. Consecutive patients admitted to a busy general surgery service from January 2000 to January 2006 were prospectively entered into the Surgical Activity Tracking System. Rigorous, systematic peer review was performed concurrently by service members on all deaths. Adjudication was later validated by an independent senior surgeon. Three methodologies of risk adjustment (University Health Consortium, Physiological and Operative Severity Score for the enUmeration of Mortality, and the Charlson index) were used and compared the "excess mortality" predicted by each to the number of potentially preventable deaths determined by peer review. A total of 9623 patients were admitted and 75 died (0.7%). University Health Consortium and Physiological and Operative Severity Score predicted an excess mortality of 62 and 65 deaths, respectively; Charlson predicted that 73% of the cohort would be dead in 1 year. Concurrent and retrospective peer review found that death was potentially preventable in only 22 and 21 patients, respectively. Peer adjudication and extensive clinical review adds much to the analysis of an adverse outcome, similar to the "black box" in an airplane crash. Although methods of risk adjustment may be helpful in identifying patients for peer review, they should be used for internal process improvement and not published as metrics of hospital or provider performance.
    Annals of surgery 09/2010; 252(3):452-8; discussion 458-9. · 7.90 Impact Factor
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    ABSTRACT: Angiopoetin- (Ang-) 1 inhibits and Ang-2 promotes VEGF-mediated angiogenesis via binding to endothelial cell-bound Tie-2 receptor (Tie-2). After minimally invasive colorectal resection (MICR), Ang-1 levels decrease and Ang-2 levels increase, which may stimulate angiogenesis in wounds and residual tumor foci. Soluble Tie-2 (sTie-2) modulates the effects of free Ang-1 and Ang-2 by binding to them. This study assessed perioperative MICR plasma sTie-2 levels. Blood samples were taken preoperatively (PreOp) and on postoperative days (POD) 1 and 3 from 50 cancer and 53 benign disease MICR patients. In a subgroup, a fourth sample was taken between POD7 and POD13 and bundled as a single time point. sTie-2 levels (ng/ml) were determined via ELISA. The mean and SD were determined at each time point. The t test used for analysis. PreOp plasma sTie-2 levels were significantly higher in the benign group (27.6 ± 10.2) than in the cancer group (22.9 ± 7.9). A significant drop from PreOp occurred in sTie-2 levels in the cancer group on POD1 (20.0 ± 7.4) and POD3 (21.0 ± 6.6) and in the benign group on POD1 (24.8 ± 9.1). The benign group's POD3 and the cancer group's POD7-13 sTie-2 levels were statistically similar to the PreOp levels while the benign group's POD7-13 level was significantly higher. PreOp sTie-2 levels were significantly lower in cancer patients. MICR is associated with a significant short-lived decrease in plasma sTie-2 levels in cancer patients on POD1 and 3, which may briefly inhibit VEGF-mediated angiogenesis. The benign group's early results were similar.
    Surgical Endoscopy 03/2010; 24(10):2581-7. · 3.43 Impact Factor

Publication Stats

3k Citations
778.30 Total Impact Points

Institutions

  • 1993–2013
    • University of Vermont
      • Department of Surgery
      Burlington, VT, United States
  • 2010–2011
    • Aurora St. Luke's Medical Center
      Milwaukee, Wisconsin, United States
  • 2009
    • CUNY Graduate Center
      New York City, New York, United States
  • 2006–2009
    • Fletcher Allen Health Care
      Burlington, Vermont, United States
  • 2008
    • Massachusetts General Hospital
      • Department of Surgery
      Boston, MA, United States
  • 2004
    • Universität Regensburg
      Ratisbon, Bavaria, Germany
  • 1991–1996
    • Burlington College
      Burlington, Vermont, United States