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711.

Background  

Melanoma is the most aggressive form of skin cancer and the most rapidly expanding cancer in terms of worldwide incidence. Chemotherapeutic approaches to treat melanoma have had only marginal success. Previous studies in mice demonstrated that a high diluted complex derived from Calcarea carbonica (M8) stimulated the tumoricidal response of activated lymphocytes against B16F10 melanoma cells in vitro.  相似文献   
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OBJECTIVE: Large databases composed of well-designed prospectively collected cohort data provide an opportunity to examine and compare healthcare treatments in actual clinical practice settings. Because the analysis of these data often leads to a retrospective cohort design, it is essential to adequately adjust for lack of balance in patient characteristics when making treatment comparisons. We used matched propensity scoring in a cohort of patients undergoing elective aneurysm repair as an illustrative example of this important statistical method that adjusts for baseline characteristics and selection bias by matching covariables. METHODS: By using prospectively collected clinical data from the National Surgical Quality Improvement Program of the Department of Veterans Affairs, we studied 30-day mortality, 1-year survival, and postoperative complications in 1904 patients who underwent elective AAA repair (endovascular aneurysm repair [EVAR], n=717 (37.7%); open aneurysm repair, n=1187 [62.3%]) at 123 Veterans Health Administration's hospitals between May 1, 2001, and September 30, 2003. In bivariate analysis, patient characteristics and operative and hospital variables were associated with both type of surgery and outcomes of surgery. Therefore, the predicted probability of receiving EVAR was tabulated for all patients by using multiple logistic regression to control for 32 independent demographic and clinical characteristics and then stratified into 5 groups. Patients were matched within strata based on similar levels of the independent measures (a propensity score technique), creating a pseudo-randomized control design. The proportion of patients with the morbidity and mortality outcomes was then compared between the EVAR and open procedures within strata to control for selection. RESULTS: Patients undergoing EVAR had significantly lower unadjusted 30-day (3.1% versus 5.6%, P=.01) and 1-year mortality (8.7% versus 12.1%, P=.018) than patients undergoing open repair. By using propensity scoring, the proportions of EVAR patients experiencing 30-day mortality were equal or less than patients undergoing open procedures for all levels of probability and decreased as the probability of EVAR increased. Furthermore, propensity scoring also showed that patients having EVAR had lower 1-year mortality and experienced fewer perioperative complications. CONCLUSIONS: We used a propensity score approach to examine outcomes after elective AAA repair to statistically control for many factors affecting both treatment selection and outcome. Patients who underwent elective EVAR had substantially lower perioperative mortality and morbidity rates compared with patients having open repair, which was not explained solely by patient selection in an observational dataset.  相似文献   
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OBJECTIVE: The purpose of this study was to determine the relationship between the American Society of Anesthesiologists' Physical Status (ASA PS) classifications and the other National Surgical Quality Improvement Program (NSQIP) preoperative risk factors. BACKGROUND: The ASA PS has been shown to predict morbidity and mortality in surgical patients but is inconsistently applied and clinically imprecise. It is desirable to have a method for validating ASA PS classification levels. METHODS: The NSQIP preoperative risk factors, including ASA PS, were recorded from a random sample of 5878 surgical patients on 6 services between October 1, 2001 and September 30, 2003 at the University of Kentucky Medical Center. Mortality, morbidity, costs, and length of stay were obtained and compared across ASA PS levels. The ability of 1) ASA PS alone, 2) the other NSQIP risk factors, and, 3) all factors combined to predict outcomes was analyzed. A model using the other NSQIP risk factors was developed to predict ASA PS. RESULTS: ASA PS alone was a strong predictor of outcomes (P < 0.01). However, the other NSQIP risk factors were better predictors as a group. There was significant interdependence between the ASA PS and the other NSQIP risk factors. Predictions of ASA PS using the other factors showed strong agreement with the anesthesiologists' assignments. CONCLUSIONS: The NSQIP risk factors other than ASA PS can and should be used to validate ASA PS classifications.  相似文献   
715.
OBJECTIVE: Three main types of anesthesia are used for infrainguinal bypass: general endotracheal anesthesia (GETA), spinal anesthesia (SA), and epidural anesthesia (EA). We analyzed a large clinical database to determine whether the type of anesthesia had any effect on clinical outcomes in lower extremity bypass. METHODS: This study is an analysis of a prospectively collected database by the National Surgical Quality Improvement Program (NSQIP) of the Veterans Affairs Medical Centers. All patients from 1995 to 2003 in the NSQIP database who underwent infrainguinal arterial bypass were identified via Current Procedural Terminology codes. The 30-day morbidity and mortality outcomes for various types of anesthesia were compared by using univariate analysis and multivariate logistic regression to control for confounders. RESULTS: The NSQIP database identified 14,788 patients (GETA, 9757 patients; SA, 2848 patients; EA, 2183 patients) who underwent a lower extremity infrainguinal arterial bypass during the study period. Almost all patients (99%) were men, and the mean age was 65.8 years. The type of anesthesia significantly affected graft failure at 30 days. Compared with SA, the odds of graft failure were higher for GETA (odds ratio, 1.43; 95% confidence interval [CI], 1.16-1.77; P = .001). There was no statistically significant difference in 30-day graft failure between EA and SA. Regarding cardiac events, defined as postoperative myocardial infarction or cardiac arrest, patients with normal functional status (activities of daily living independence) and no history of congestive heart failure or stroke did worse with GETA than with SA (odds ratio, 1.8; 95% CI, 1.32-2.48; P < .0001). There was no statistically significant difference between EA and SA in the incidence of cardiac events. GETA, when compared with SA and EA, was associated with more cases of postoperative pneumonia (odds ratio: 2.2 [95% CI, 1.1-4.4; P = .034]. There was no significant difference between EA and SA with regard to postoperative pneumonia. Compared with SA, GETA was associated with an increased odds of returning to the operating room (odds ratio, 1.40; 95% CI, 1.20-1.64; P < .001), as was EA (odds ratio, 1.17; 95% CI, 1.05-1.31; P = .005). GETA was associated with a longer surgical length of stay on univariate analysis, but not after controlling for confounders. There was no significant difference in 30-day mortality among the three groups with univariate or multivariate analyses. CONCLUSIONS: Although GETA is the most common type of anesthesia used in infrainguinal bypasses, our results suggest that it is not the best strategy, because it is associated with significantly worse morbidity than regional techniques.  相似文献   
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OBJECTIVE: The objective of this study was to identify the determinants of 30-day postoperative mortality and long-term survival after major surgery as exemplified by 8 common operations. SUMMARY BACKGROUND DATA: The National Surgical Quality Improvement Program (NSQIP) database contains pre-, intra-, and 30-day postoperative data, prospectively collected in a standardized fashion by a dedicated nurse reviewer, on major surgery in the Veterans Administration (VA). The Beneficiary Identification and Records Locator Subsystem (BIRLS) is a VA file that depicts the vital status of U.S. veterans with 87% to 95% accuracy. METHODS: NSQIP data were merged with BIRLS to determine the vital status of 105,951 patients who underwent 8 types of operations performed between 1991 and 1999, providing an average follow up of 8 years. Logistic and Cox regression analyses were performed to identify the predictors of 30-day mortality and long-term survival, respectively. RESULTS: The most important determinant of decreased postoperative survival was the occurrence, within 30 days postoperatively, of any one of 22 types of complications collected in the NSQIP. Independent of preoperative patient risk, the occurrence of a 30-day complication in the total patient group reduced median patient survival by 69%. The adverse effect of a complication on patient survival was also influenced by the operation type and was sustained even when patients who did not survive for 30 days were excluded from the analyses. CONCLUSIONS: The occurrence of a 30-day postoperative complication is more important than preoperative patient risk and intraoperative factors in determining the survival after major surgery in the VA. Quality and process improvement in surgery should be directed toward the prevention of postoperative complications.  相似文献   
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The findings presented in this discussion seek to make a contribution to quality of life (QOL) research, by highlighting the import of factors affecting the communication of primary stage head and neck cancer patient's experiences of suffering after treatments by their clinicians. Qualitative research methodology based on open-ended interviews with 18 survivors of American Joint Committee on Cancer (AJCC) Stage I and Stage II, squamous cell carcinoma of the head and neck (SCCHN) were used. The interviews were transcribed verbatim and thematically analysed. In this preliminary analysis, three important themes emerged: (1) a self diminished by cancer; (2) the fear of addiction to pain medications; and (3) hopelessness and the loss of meaning in life after SCCHN. Our present findings indicate that SCCHN patients understand their experiences of cancer and under-report their experiences of suffering mainly because of fear. These include fears of: being further diminished by SCCHN, fears of addiction, and an inability to cope with the additional losses associated with SCCHN. As a consequence, and perhaps, because of a failure the part of clinicians and patients to adequately address these fears, SCCHN patients may also experience greater psychological morbidity, becoming fatalistic about biomedicine's ability to restore them to health after cancer, or related symptoms, including pain, despite being 'cured.' This study provides a perspective on why this under-reporting occurs, thereby potentially enhancing clinician-patient communication and the QOL of SCCHN patients who present with curable disease.  相似文献   
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