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71.

Background

There is increased awareness that, to minimize variation in clinician practice and improve quality, performance reporting should be implemented at the provider level. This optimizes physician engagement and creates a sense of professional responsibility for quality and performance measurement at the individual and organizational levels.

Methods

Individual provider level reporting was implemented within a provincial health region involving 56 clinicians (general surgeons, surgical oncologists, urologists and pathologists). The 2 surgical pathology indicators chosen were colorectal cancer (CRC) lymph node retrieval rate and pT2 prostate cancer margin positivity rate. Surgical resections for all prostate and colorectal cancer performed between Jan. 1, 2011, and Mar. 30, 2012, were included. We used a pre- and postsurvey design to obtain physician perceptions and focus groups with program leadership to determine organizational impact.

Results

Survey results showed that respondents felt the data provided in the reports were valid (67%), consistent with expectations (70%), maintained confidentiality (80%) and were not used in a punitive manner (77%). During the study period the pT2 prostate margin positivity rate decreased from 57.1% to 27.5%. For the CRC lymph node retrieval rate indicator, high baseline performance was maintained.

Conclusion

We developed a robust process for providing physicians with confidential, individualized surgical and pathology quality indicator reports. Our results reinforce the importance of individual physician feedback as a strategy for improving and sustaining quality in surgical and diagnostic oncology.  相似文献   
72.
BACKGROUND: The aim of this experimental study was to investigate the effect of mycophenolate mofetil (MMF) during the three phases of colonic anastomosis healing and specifically to check the effect of MMF on the expression of transforming growth factor-beta1 (TGF-beta1), one of the most important growth factors contributing to mechanical stability of colonic anastomosis. MATERIALS AND METHODS: Sixty male Wistar rats underwent colonic resection and end-to-end anastomosis. The animals were divided into two groups, a study group given MMF 40 mg/kg, intraduodenally and a control group given vehicle. The rats were sacrificed at 3, 7, and 14 days (10 animals in each group). The anastomoses were tested by measuring bursting pressure and hydroxyproline content. Histological examination and immunohistochemical expression of TGF-beta1 also were assessed. RESULTS: The mean bursting pressure in the study group was significantly lower on day 3 and 7, but there was no statistical significance on day 14. The mean hydroxyproline content was lower in the study group on days 3, 7, and 14. Histology showed decreased number of macrophages and fibroblasts on days 3 and 7 but no difference on day 14. The expression of TGF-beta1 was significantly reduced in the study group, with the difference being more pronounced on days 3 and 7. CONCLUSION: MMF weakens the integrity of colonic anastomosis, and this effect is more significant during the inflammatory phase of healing. MMF has a negative effect on macrophages and TGF-beta1 expression, resulting in decreased collagen accumulation at the anastomosis.  相似文献   
73.
74.
Chronic corrosive strictures of the upper cervical esophagus and hypopharynx resulting from ingestion of caustic substances are a challenging surgical entity when repeated endoscopic dilatations fail to yield satisfactory results. Restoring the continuity of the upper digestive tract by esophageal substitution at healthy tissue margins not only compromises the integrity of the swallowing mechanism, but also often requires the performance of a tracheostomy in order to ensure avoidance of recurrent aspirations. We describe three cases of corrosive upper cervical esophageal strictures treated with intraoperative dilatation of the proximal hypopharyngeal stump and concurrent ‘stenting’ of the pharyngeal anastomosis with the conduit replacing the esophagus. All patients tolerated the procedure well. Avoidance of both impairment of deglutition and respiratory complications, as well as restoration of normal esophageal function, was successfully accomplished.  相似文献   
75.
Renal cell carcinoma produces neoplasmatic thrombus that usually invades and progressively grows into the endorenal veins. The thrombus may extend into the ipsilateral renal vein or the inferior vena cava in 15-20% and 8-15% of cases, respectively. These tumors are classified into four categories (I, II, III, and IV) according to the level of cephalad extension of thrombus into the inferior vena cava. The purpose of this study was to assess the surgical strategy for cases of renal tumor thrombus invading the vena cava. We retrospectively reviewed the records of 10 patients with renal cell carcinoma, who underwent in our institution radical nephrectomy and resection of vena cava thrombus between January 1997 and December 2004. Four patients were classified as level I, four were level II, and two were level III. In all cases, the thrombus was removed through a small cavotomy without cardiopulmonary bypass and the cavotomy was closed primarily. Pringle’s maneuver was performed in the two level III cases. There were no perioperative pulmonary embolisms or deaths, and the mean hospital stay was 8 ± 1.1 days. The mean survival was 21.8 ± 8 months, and the vena cava remained patent for this period. Tumor thrombectomy improves the prognosis and the quality of life of these patients, and in most of cases the surgical technique, although challenging, carries a low morbidity and mortality rate.  相似文献   
76.
Introduction Neuronal inhibitory reflex mechanisms contribute to postoperative ileus after abdominal surgery. During this condition, sensory neurons in the brainstem are activated. We aimed to determine the contribution of capsaicin-sensitive afferents to central vagal sensitivity in mice during postoperative ileus. Materials and methods Under enflurane anesthesia, C57BL/6 mice were laparotomized and the small bowel was manipulated to induce ileus or was left untouched as a sham-treatment group. A subgroup of ileus animals was pre-treated with Capsaicin (1 μm/kg, i.p.) 48 h before small bowel manipulation. The animals were killed 24 h later and the brainstem was removed for Fos immunohistochemistry, which was quantified in the nucleus of the solitary tract (nTS). Spontaneous jejunal motility was recorded in vitro. Leukocyte infiltration in the intestinal muscularis was studied by myeloperoxidase staining as an index of postoperative inflammation. Results There were 30±9 Fos-positive neurons counted in the nTS after ileus and 6±2 in sham controls (Bregma −7.70 mm, P=0.01). A reduction to 8±3 was observed after Capsaicin pre-treatment in ileus animals (P<0.05). Peak amplitudes of spontaneous jejunal motility were 2±0.3 cmH2O during postoperative ileus, 3±0.6 cmH2O after ileus with capsaicin pre-treatment, and 10±2 cmH2O in control animals (N=6, both P<0.05). The number of leukocytes infiltrating the muscularis was 39±9/mm2 during ileus and 1.8±1/mm2 in controls (mean±SEM, P<0.01, N=6). After capsaicin, this number increased to 72±28/mm2 in ileus animals (P<0.05 vs control animals, N=7). Conclusion The inhibition of capsaicin-sensitive vagal afferent pathways appears to boost rather than to attenuate the inflammatory response during postoperative ileus, while intestinal motility remained unchanged. This suggests a protective role of the capsaicin-sensitive afferent innervation for the inflammatory phase of postoperative ileus. Best of Forum Papers presented at the Annual Meeting of the German Society of Surgery, 2–5 May 2006, Berlin, Germany  相似文献   
77.
Objectives:To investigate root resorption after 6 months of active orthodontic treatment and its relation to possible risk factors.Materials and Methods:Ninety-seven patients (10–18 years) with a Class I malocclusion and crowding treated with fixed appliance and premolar extractions were examined with cone beam computed tomography before and after 6 months of active treatment. The exposure covered all teeth from first molar to first molar in both jaws. The Malmgren index was used to evaluate the degree of root resorption. Irregular root contour (score 1) was seen in most teeth already before active treatment, and therefore resorptions were registered only as score 2 (<2 mm, minor resorption) or higher.Results:Minor root resorption was noted in 10% of the patients and severe root resorption, >2 mm (score 3) was found in four patients. Root resorption was more frequently seen in the upper jaw, especially the incisors. There was no statistically significant correlation of root resorption with any of the selected risk factors.Conclusions:After 6 months of treatment, clinically significant resorption was diagnosed in 4% of the patients, ie, in 96% of the patients the radiographic examination did not reveal any significant information. The selected risk factors did not have any impact on the amount of resorption after 6 months of active treatment.  相似文献   
78.
Long-term results of thin corneas after refractive laser surgery   总被引:1,自引:0,他引:1  
PURPOSE: To report the long-term refractive results of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) in patients with thin corneas. DESIGN: A long-term, retrospective, non-randomized follow-up study. METHODS: Sixty-three patients (124 eyes) (28 males and 35 females), who had a preoperative central corneal thickness (CCT) of less than 500 microns and completed at least one year of follow-up examinations after surgery. Thirty-five patients (68 eyes) underwent PRK and 28 patients (56 eyes) underwent LASIK. RESULTS: Mean preoperative corneal pachymetry was 484.95 +/- 6.65 microm (range, 470 to 498 microm) and 482.38 +/- 10.73 microm (range, 453 to 499 microm) for LASIK and PRK, respectively. No intraoperative complications were found in both groups. None of the included eyes developed postrefractive corneal ectasia. The mean predictability for the PRK group was 0.08 diopters (D) with a standard deviation of 0.40 D (range, -1.38 to 1.00 D), and the mean predictability for the LASIK group was 0.14 D with a standard deviation of 0.55 D (range, -1.25 to 1.33 D). CONCLUSIONS: Refractive laser surgery with LASIK or PRK in patients with thin corneas (less than 500 microm) seems to be a safe and predictable technique for myopic refractive corrections.  相似文献   
79.
Oxidized organic aerosol (OOA) is a major component of ambient particulate matter, substantially impacting climate, human health, and ecosystems. OOA is readily produced in the presence of sunlight, and requires days of photooxidation to reach the levels observed in the atmosphere. High concentrations of OOA are thus expected in the summer; however, our current mechanistic understanding fails to explain elevated OOA during wintertime periods of low photochemical activity that coincide with periods of intense biomass burning. As a result, atmospheric models underpredict OOA concentrations by a factor of 3 to 5. Here we show that fresh emissions from biomass burning exposed to NO2 and O3 (precursors to the NO3 radical) rapidly form OOA in the laboratory over a few hours and without any sunlight. The extent of oxidation is sensitive to relative humidity. The resulting OOA chemical composition is consistent with the observed OOA in field studies in major urban areas. Additionally, this dark chemical processing leads to significant enhancements in secondary nitrate aerosol, of which 50 to 60% is estimated to be organic. Simulations that include this understanding of dark chemical processing show that over 70% of organic aerosol from biomass burning is substantially influenced by dark oxidation. This rapid and extensive dark oxidation elevates the importance of nocturnal chemistry and biomass burning as a global source of OOA.

Highly oxidized organic aerosol (OOA) is a dominant component of particulate matter air pollution globally (13); however, sources of OOA remain uncertain, limiting the ability of models to accurately represent OOA and thus predict the associated climate, ecosystem, and health implications (4, 5). The current conceptual model of OOA formation suggests that anthropogenic OOA predominantly originates from the oxidation of volatile (VOCs), intermediate volatility (IVOCs), and semivolatile (SVOCs) organic compounds by the OH radical, resulting in lower-volatility products that condense to the particle phase (6). As the OH radical is formed through photolysis and has a very short atmospheric lifetime [less than a second (7)], this oxidation mechanism only occurs in the presence of sunlight. Further, the time scale for OOA formation through oxidation with OH in models is on the order of a few days (8). While this understanding is sufficient in explaining OOA concentrations in summer or periods with high solar radiation, atmospheric models fail to reproduce the observed concentration of OOA in the ambient atmosphere during winter and low-light conditions (9, 10). Fountoukis et al. (9) found simulated OOA concentrations significantly underestimated in wintertime Paris. Tsimpidi et al. (10) also reported an underprediction of simulated OOA globally in winter, suggesting missing sources of both primary OA (POA) and secondary formation pathways. This underproduction suggests a possible overlooked conversion pathway of organic vapors or particles to OOA that is not accounted for in current chemical transport and climate models.As stricter controls on fossil fuel combustion are implemented, residential biomass burning (BB) as a source of heating or cooking is becoming an increasingly important source of OA in urban environments (1, 11, 12). Further, increasing rates of wildfires from climate change are increasing the frequency of smoke-impacted days in urban areas (1214). BB emissions include high concentrations of POA, SVOCs, IVOCs, and VOCs (15, 16), thus making BB a key source of OOA. Previous research has focused on quantifying the concentration of OOA formed through photochemical oxidation reactions (i.e., OH) with BB emissions (17, 18). However, oxidation of BB emissions in low or no sunlight is less well understood and is not included in chemical transport models. As opposed to OH, the NO3 radical is formed through reactions with NO2 and O3 and is rapidly lost in the presence of sunlight (19). Thus, the NO3 radical is only available in significant concentrations at night or other low-light conditions (20, 21). Previous research has established that biogenic VOCs may undergo oxidation at night when mixed with anthropogenic emissions containing NO2 and O3 (19, 2227). There have been only a few studies that consider that nighttime oxidation of residential wood combustion may proceed through similar pathways (2831); however, the magnitude and relevance to observed OOA in the ambient atmosphere has not yet been established. By combining laboratory experiments and ambient observations to inform a chemical transport model, we present strong evidence that nighttime oxidation of BB plumes (proceeding through reactions with O3 and the NO3 radical) is an important source of OOA.  相似文献   
80.
BACKGROUND: Controversy exists regarding inhibition of ischemic preconditioning in hyperlipidemic animals. In this study, we tested the hypothesis that hyperlipidemia inhibits the normal reduction of myocardial ischemia on repeated balloon inflations (BIs) during angioplasty. METHODS: We studied 33 patients undergoing coronary angioplasty. All underwent a minimum of three BIs. Patients were grouped according to the following plasma cholesterol levels: 13 patients had total cholesterol levels < 200 mg/dL (the normal cholesterol group); and 20 patients had total cholesterol levels > or = 200 mg/dL (the elevated cholesterol group). Surface ST-segment elevations were recorded at the end of each BI. RESULTS: In the normal cholesterol group, the mean (+/- SD) ST-segment elevation decreased from 0.21 +/- 0.15 mV during the first BI to 0.11 +/- 0.11 mV during the third BI (p < 0.05). In the elevated cholesterol group, the respective decrease was from 0.18 +/- 0.16 to 0.14 +/- 0.15 mV (p = not significant) [between-group comparisons: F = 3.97; p = 0.02]. The decrease in ST-segment elevation was correlated with the total cholesterol levels (r = -0.48; p = 0.005), the low-density lipoprotein (LDL) cholesterol levels (r = -0.50; p = 0.003), and the high-density lipoprotein/LDL levels (r = 0.44; p = 0.01). CONCLUSION: Hyperlipidemia prevents the normal reduction of myocardial ischemia on repeated BIs during angioplasty. This leads to the clinical implication that reduction of cholesterol plasma levels, apart from its other known benefits, could also have a beneficial effect on cardioprotection.  相似文献   
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