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William C Nugent

Publications and source records attributed to William C Nugent.

14 recordsLinked to original sources
PubMed2006

Comparison of three measurements of cardiac surgery mortality for the Northern New England Cardiovascular Disease Study Group.

BACKGROUND: There is no consensus on the optimal period during which to assess death after coronary artery bypass graft (CABG) surgery. Three measures are commonly used: in-hospital, 30-day, and procedural (either in-hospital or 30-day) mortality. We used a regional database to calculate the CABG mortality rate using each of these mortality measures. METHODS: Data were collected prospectively on 31,592 consecutive isolated CABG surgeries in northern New England between January 1992 and December 2001. These data were linked to the National Death Index to obtain vital status through December 2001, and used to calculate 30-day and procedural mortality rates. Procedural mortality was defined as death occurring either within the hospital setting or within 30 days of the index procedure. Regional registry data were used to calculate in-hospital mortality rates. RESULTS: Mortality rates and their 95% confidence intervals were calculated. In all but one medical center, the in-hospital mortality was the lowest rate, while in all centers the procedural mortality rate was the highest. There were 1,082 deaths captured by the procedural mortality measure. Of these, 927 were included in the in-hospital mortality measure; 956 occurred within 30 days of surgery. CONCLUSIONS: Each of the measures studied has its advantages and may be used to assess the mortality outcomes of cardiac surgery. The more important issue other than the specific measure used is our ability to measure and validate it conveniently and accurately in actual practice.

Coronary Artery Bypass↗
PubMed2005

The preoperative intraaortic balloon pump in coronary bypass surgery: a lack of evidence of effectiveness.

BACKGROUND: There is limited evidence demonstrating the effectiveness of preoperative intraaortic balloon pump (IABP) use in isolated coronary artery bypass graft (CABG) surgery. A single-center randomized trial demonstrated its benefit. We undertook a multicenter observational study to verify this finding. METHODS: In 29,950 consecutive patients undergoing isolated CABG between 1995 and 2000 at 10 centers, we compared patients with and without a preoperative IABP. We also compared the effect of preoperative IABP use within 7 high-risk clinical subgroups. To validate the previous randomized trial, patients with any 2 of the following were also analyzed: left main > 70%, ejection fraction < 40%, redo CABG, or preoperative intravenous nitroglycerin. RESULTS: Preoperative IABPs were used in 1896 patients (6.3%). These patients had more comorbid conditions and a higher crude mortality than those who did not have preoperative IABPs (9.5% vs 2.3%, P < .0001). Preoperative IABP patients were caliper matched to non-preoperative IABP patients using a propensity score. Excess mortality associated with preoperative IABP persisted (9.2% vs 5.8%, P = .0004). In 7 high-risk subgroups, mortality was significantly higher with preoperative IABP. We used propensity caliper matching to compare preoperative IABP with non-preoperative IABP patients who met trial criteria (n = 4332). Preoperative IABP was associated with higher mortality (11.0% vs 6.5%, P = .0009). Removing emergency patients did not alter results. CONCLUSIONS: Use of preoperative IABPs was consistently associated with higher mortality. Despite detailed statistical analysis, we were unable to show benefit from preoperative IABP use or confirm the results of a single-center trial that demonstrated its benefit. Assessment of preoperative IABP efficacy will require a randomized trial.

Aged↗
PubMed2005

Building and supporting sustainable improvement in cardiac surgery: the Northern New England experience.

The Northern New England Cardiovascular Disease Study Group (NNECDSG) was formed as a regional clinical database that would allow clinicians to track outcomes after cardiac interventions. The purpose of the NNECDSG would be to use its database and organizational structure to seek best practices and disseminate information aimed at improving results for patients undergoing cardiovascular interventions. Since 1987, this voluntary regional collaborative of clinicians, hospital administrators, and health care research personnel has tracked consecutive cardiovascular interventions performed throughout Northern New England and reported its findings to the clinicians. Collaboration between NNECDSG institutions has led to progressive refinements in the clinical database, institutional site visits, efforts to understand and standardize ideal processes of care, risk-stratification tools to aid in decision making, and most recently, tools to track and report on appropriateness of interventions based on national criteria. As a result of these efforts, mortality rates after coronary bypass graft surgery have steadily declined and the variation in mortality rates between institutions has disappeared.

Cardiac Output, Low↗
PubMed2005

Improving outcomes of cardiac surgery through cooperative efforts: the northern new England experience.

Coronary artery bypass graft (CABG) surgery is an effective procedure for relieving angina. In 1987, the Health Care Financing Administration published surgeon-specific mortality rates, prompting the formation of the Northern New England Cardiovascular Disease Study Group (NNECDSG). This regional collaborative of all medical centers performing cardiovascular procedures in northern New England began collecting data concerning patient and disease characteristics and adverse outcomes in an effort to improve the care provided to their patients. An initial quality improvement effort resulted in a 24% reduction in in-hospital mortality. Subsequent efforts have involved the development and implementation of quality improvement initiatives to redesign care to reduce further a patient's risk of mortality and other morbidities. More recently, we have adopted this model to reduce a patient's risk of neurologic injury. In this study, we are intensively monitoring patients intraoperatively with transcranial Doppler and near infrared spectroscopy as well as collecting hemodynamic data, and are synchronizing this data with a video of the surgical site. The goal of the study is to identify the association between clinical strategies and the development of the precursors of neurologic injury and use a quality improvement approach to redesign care to reduce occurrence of these precursors.

Cardiac Surgical Procedures↗
PubMed2004

Epidermal growth factor receptor tyrosine kinase inhibition represses cyclin D1 in aerodigestive tract cancers.

PURPOSE: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are active in cancer therapy. Mechanisms engaged during these clinical responses need to be determined. We reported previously that epidermal growth factor stimulation markedly increased cyclin D1 protein expression in human bronchial epithelial (HBE) cells, and this was opposed by chemoprevention with all-trans-retinoic acid. The current study sought to determine whether the EGFR TKI erlotinib repressed cyclin D1 protein expression in immortalized HBE cells, lung cancer cell lines, and clinical aerodigestive tract cancers. EXPERIMENTAL DESIGN: The BEAS-2B immortalized HBE cell line was exposed to varying concentrations of erlotinib, and effects on proliferation, cell cycle distribution, G1 cyclin expression, and cyclin D1 reporter activity were measured. Non-small-cell lung cancer cell lines were also evaluated for changes in proliferation and cyclin protein expression after erlotinib treatments. A proof of principle clinical trial was conducted. During this study, patients underwent a 9-day course of erlotinib treatment. Pretreatment and posttreatment tumor biopsies were obtained, and changes in candidate biomarkers were determined by immunostaining. Plasma pharmacokinetics and tumor tissue erlotinib concentrations were measured. RESULTS: Erlotinib, at clinically achievable dosages, repressed BEAS-2B cell growth, triggered G1 arrest, and preferentially reduced cyclin D1 protein expression and transcriptional activation. Erlotinib also preferentially repressed proliferation and cyclin D1 protein expression in responsive, but not resistant, non-small-cell lung cancer cell lines. This occurred in the presence of wild-type EGFR sequence at exons 18, 19, and 21. Five patients were enrolled onto an erlotinib proof of principle clinical trial, and four cases were evaluable. Pharmacokinetic studies established therapeutic erlotinib plasma levels in all patients, but tissue levels exceeding 2 micromol/L were detected in only two cases. Notably, these cases had pathological evidence of response (necrosis) in posttreatment biopsies as compared with pretreatment biopsies. In these cases, marked repression of cyclin D1 and the proliferation marker Ki-67 was detected by immunohistochemical assays. Cases without pathological response to erlotinib did not exhibit changes in cyclin D1 or Ki-67 immunohistochemical expression and had much lower erlotinib tissue levels than did responding cases. CONCLUSIONS: Taken together, these in vitro and in vivo findings provide direct evidence for repression of cyclin D1 protein as a surrogate marker of response in aerodigestive tract cancers to erlotinib treatment. These findings also provide a rationale for combining an EGFR TKI with an agent that would cooperatively repress cyclin D1 expression in clinical trials for aerodigestive tract cancer therapy or chemoprevention.

Biomarkers, Tumor↗
PubMed2004

Effect of diabetes and associated conditions on long-term survival after coronary artery bypass graft surgery.

BACKGROUND: The effects of diabetes on short-term results of coronary artery bypass graft (CABG) surgery are known, but less is known about the long-term effects of diabetes and diabetic-related sequelae for patients undergoing this surgery. We studied the 10-year survival of nondiabetic and diabetic patients undergoing CABG surgery. METHODS AND RESULTS: A prospective regional cohort study was conducted of 36,641 consecutive isolated CABG patients in northern New England from 1992 through 2001. Patient records were linked to the National Death Index to assess mortality. There were 154,140 person-years of follow-up and 5779 deaths. Kaplan-Meier techniques were used. Survival was stratified into three categories: no diabetes, diabetes without peripheral vascular disease and renal failure, and diabetes with peripheral vascular disease and/or renal failure. The overall annual incidence rate of death was 3.7 deaths per 100 person-years. Annual incidence rates for nondiabetic subjects and diabetic subjects were similar: 3.1 deaths per 100 person-years and 4.4 deaths per 100 person-years, respectively. The annual incidence rate for diabetic subjects with renal failure, peripheral vascular disease, or both was 9.4 deaths per 100 person-years. The log-rank test showed that the survival curves were significantly different (P<0.001). CONCLUSIONS: Patients that have diabetes without the sequelae of renal failure and/or peripheral vascular disease have long-term survival similar to but slightly less than patients without diabetes who undergo CABG surgery. Survival of CABG surgery patients with diabetes is greatly affected by associated comorbidities of peripheral vascular disease and renal failure. This knowledge may help guide the patient as well as the cardiologist and cardiac surgeon in making appropriate decisions in these critically ill patients.

Cause of Death↗
PubMed2004

The Society of Thoracic Surgeons practice guideline series: transmyocardial laser revascularization.

BACKGROUND: Patients with chronic severe angina refractory to medical therapy who cannot be completely revascularized with either percutaneous catheter intervention or coronary artery bypass graft surgery present clinical challenges. Transmyocardial laser revascularization, either as sole therapy or as an adjunct to coronary artery bypass graft surgery, may be appropriate for some of these patients. Although transmyocardial revascularization has consistently been demonstrated as an efficacious means of relieving angina, the mechanism of its effects are still debated, and criteria for the selection of patients for this novel therapy have not been adequately defined. METHODS: We reviewed the available evidence to allow us to make recommendations for the appropriate therapeutic applications of transmyocardial revascularization following the format of the American Heart Association and the American College of Cardiology guidelines for diagnostic and therapeutic procedures. Our recommendations were classified as class I, IIA, IIB, or III. For each recommendation we defined the level of supporting evidence as A, B, or C. RESULTS: We identified class I indications for transmyocardial revascularization as sole therapy and class IIA indications for transmyocardial revascularization as an adjunct to coronary artery bypass graft surgery with levels of evidence A and B, respectively. CONCLUSIONS: Transmyocardial laser revascularization may be an acceptable form of therapy for selected patients: as sole therapy for a subset of patients with refractory angina and as an adjunct to coronary artery bypass graft surgery for a subset of patients with angina who cannot be completely revascularized surgically.

Angina Pectoris↗
PubMed2004

Cardiac surgery risk models: a position article.

Differences in medical outcomes may result from disease severity, treatment effectiveness, or chance. Because most outcome studies are observational rather than randomized, risk adjustment is necessary to account for case mix. This has usually been accomplished through the use of standard logistic regression models, although Bayesian models, hierarchical linear models, and machine-learning techniques such as neural networks have also been used. Many factors are essential to insuring the accuracy and usefulness of such models, including selection of an appropriate clinical database, inclusion of critical core variables, precise definitions for predictor variables and endpoints, proper model development, validation, and audit. Risk models may be used to assess the impact of specific predictors on outcome, to aid in patient counseling and treatment selection, to profile provider quality, and to serve as the basis of continuous quality improvement activities.

Bayes Theorem↗
PubMed2003

Patient characteristics can predict improvement in functional health after elective coronary artery bypass grafting.

BACKGROUND: Despite many patients undergoing coronary artery bypass grafting (CABG) to improve their functional status, literature in this area is limited. The purpose of this study is to determine the effect of CABG on the functional health of an elective population and to identify preoperative patient characteristics associated with improved functional health after surgery. METHODS: Physical and mental functional health was assessed before and 6 months after surgery with the Short-Form Health Survey (SF-36) in 1,061 consecutive patients undergoing elective, isolated CABG. Survey data were complete in 529 patients (49.9%). Preoperative information on patient demographics, severity of cardiovascular illness, and disease comorbidities was also prospectively collected. RESULTS: Six months post-CABG the mean summary score for physical function improved by 31.9% over baseline (45.1 versus 34.2, p < 0.0001). The mean summary score for mental function improved by 7.3% over baseline (51.3 versus 47.8, p < 0.0001). Overall 73.2% of patients showed improvement in physical function and 41.6% showed improvement in mental function. Multivariate logistic regression identified certain preoperative characteristics as negative correlates of a significant improvement in physical functioning: body mass index 35 kg/m2 or greater, diabetes with sequelae, chronic obstructive pulmonary disease, peripheral vascular disease, and baseline physical function. Baseline mental function and chronic obstructive pulmonary disease were identified as negative correlates and older age as a positive correlate of significant improvement in mental functioning. CONCLUSIONS: Patient characteristics exist that impact functional health after elective CABG. Knowledge of these characteristics may be helpful when counseling patients about expected improvement in functional health with CABG.

Activities of Daily Living↗
PubMed2003

A multicenter comparison of intraaortic balloon pump utilization in isolated coronary artery bypass graft surgery.

BACKGROUND: Single-center studies suggest substantial variation in intraaortic balloon pump (IABP) utilization. Our purpose is to examine IABP utilization over time and across medical centers. METHODS: This was a prospective cohort of 29,961 consecutive patients undergoing isolated coronary artery bypass graft surgery, between 1995 and 2000, at 10 centers (eight in northern New England and two in Canada). RESULTS: A total of 2,678 (8.9%) patients received an IABP. The rate of preoperative IABP insertion was 6.3%, and that of intra- or postoperative insertion was 2.6%. During the 6 years, IABP use increased from 7.0% to 10.3% (p(trend) <0.001). Preoperative IABP insertion increased from 5.4% to 7.8% (p(trend) < 0.001). There was no significant increase in intra-/postoperative IABP insertion 1.7% to 3.4% (p(trend) = 0.34). Adjustment for changes in patient and disease characteristics did not substantially alter these results. The rate of IABP use varied substantially by center, from 5.9% to 16.4% (p < 0.001). Adjustment for patient and disease characteristics resulted in variation from 4.8% to 12.8% across the 10 centers (p < 0.001). The adjusted rates of preoperative IABP insertion varied from 3.6% to 13.7% (p < 0.001), and the rates of intra-/postoperative IABP insertion ranged from 1.0% to 5.2% (p < 0.001). There was no significant correlation between the rates of preoperative and intra-/postoperative IABP use (r(s) = 0.085, p = 0.815). CONCLUSIONS: During the 6 years, there was a 47% increase in the rate of IABP utilization. Even after adjustment, there was almost threefold variation in IABP use across centers. This variation likely reflects lack of consensus on the appropriate use of the IABP in CABG patients.

Cohort Studies↗
PubMed2002

Thoracic surgery workforce: snapshot at the end of the twentieth century and implications for the new millennium.

BACKGROUND: An appropriately sized physician workforce is an essential component for healthcare planning. Contemporary economic forces and the impact of managed care have stimulated renewed interest in understanding and monitoring workforce issues. METHODS: Between August and December of 1999, the Workforce Committee of the American Association for Thoracic Surgery and The Society of Thoracic Surgeons conducted a survey detailing demographic, geographic, and socioeconomic practice characteristics of the membership. RESULTS: The 2,515 returned surveys represented a 62.6% return rate (+/- 1.6% margin of error), providing a highly statistically valid sample. Active thoracic surgeons are a mean of 50 years old, 98% men, with a high level of career satisfaction. Length of training and educational debt has been escalating. Adult cardiac surgical case volumes have increased (mean, 225 cases) and 52% of adult cardiac surgeons perform general thoracic procedures. Surgeons work 67 hours/week and 47 weeks/year. Most are organized in single specialty groups (50%) in urban areas (59%) as for-profit corporations (77%). Half of the respondents will be retired a mean of 13 years from now corresponding to a median calendar year of 2011. CONCLUSIONS: This survey highlights significant workforce retirement during the next 10 to 15 years. Currently, the workforce in thoracic surgery appears "right sized." These valuable data provide a profile of the specialty. The information enhances our ability to strategically plan.

Adult↗