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31.
In a context of growing control of health-care expenditures,it is important to assess cardiac surgical results as preciselyas possible. However, as patient population may differ significantlybetween institutions and geographic areas, comparison of absolutenumbers, such as mortality rates, is inappropriate for cost-benefitanalysis and comparison of results between institutions.1,2 Therefore, various risk stratification models have been developedto correct for differences between populations and to allowcomparison of actual outcome with predicted outcome.3 Thosemodels are increasingly used to investigate patient outcomesin relation to pre-operative patient and disease characteristics.Such models estimate coefficients for each risk factor of mortality,which are translated to risk scores. Then, the scores assignedto each risk factor are added to calculate the overall riskscore of mortality for a patient and to construct clinical riskgroups. Reference to these groups  相似文献   
32.
BACKGROUND: Of patients who have undergone gastric banding, 11-25% will require a major reoperation with band removal and conversion to another bariatric procedure after they have failed to lose sufficient weight or have developed dysphagia or reflux. The aim of this study was to evaluate the respective benefits of Roux-en-Y gastric band (RYGB) or biliopancreatic diversion with duodenal switch (BPD-DS) after failed gastric banding and whether 1 of the 2 procedures might be a better procedure for such cases. METHODS: RYGB or BPD-DS was performed according to the institutional protocols with synchronous band removal, irrespective of the reason for failure. RESULTS: Of the 53 patients, 32 underwent laparoscopic RYGB for a body mass index (BMI) of 43.1 +/- 6.4 kg/m(2) (BMI 45.8 +/- 6.4 kg/m(2) before laparoscopic adjustable gastric banding) and 21 underwent BPD-DS for a BMI of 46.0 +/- 5.5 kg/m(2) (BMI 49.6 +/- 5.2 kg/m(2) before laparoscopic adjustable gastric banding). BPD-DS required significantly longer operative times (239.7 +/- 55.8 versus 135 +/- 26.7 minutes) and resulted in more complications (62% versus 12.5%; P <.002). No patients died postoperatively. The 2 groups of patients had a similar BMI at 12 and 18 months after revision (BMI 33.4 +/- 5.6 kg/m(2) and 31.4 +/- 3.5 kg/m(2)). The weight loss was greater after BPD-DS than after RYGB compared with the prerevision weight loss (66.2% versus 58.8% excess weight loss) or initial weight (73% versus 61.8%), although this was not significant. CONCLUSION: Despite an excessive rate of complications that were, in part, related to the learning curve in this series, BPD-DS resulted in greater weight loss compared with RYGB. However, both procedures were successful after failed gastric banding. A more accurate definition of failure could help to determine the respective indications for revisional surgery.  相似文献   
33.
OBJECTIVES: To characterize remaining coronary artery motion of beating pig hearts after stabilization with an 'Octopus' using an optical remote analysis technique. METHODS: Three pigs (40, 60 and 65 kg) underwent full sternotomy after receiving general anesthesia. An 8-bit high speed black and white video camera (50 frames/s) coupled with a laser sensor (60 microm resolution) were used to capture heart wall motion in all three dimensions. Dopamine infusion was used to deliberately modulate cardiac contractility. Synchronized ECG, blood pressure, airway pressure and video data of the region around the first branching point of the left anterior descending (LAD) coronary artery after Octopus stabilization were captured for stretches of 8 s each. Several sequences of the same region were captured over a period of several minutes. Computerized off-line analysis allowed us to perform minute characterization of the heart wall motion. RESULTS: The movement of the points of interest on the LAD ranged from 0.22 to 0.81 mm in the lateral plane (x/y-axis) and 0.5-2.6 mm out of the plane (z-axis). Fast excursions (>50 microm/s in the lateral plane) occurred corresponding to the QRS complex and the T wave; while slow excursion phases (<50 microm/s in the lateral plane) were observed during the P wave and the ST segment. The trajectories of the points of interest during consecutive cardiac cycles as well as during cardiac cycles minutes apart remained comparable (the differences were negligible), provided the hemodynamics remained stable. Inotrope-induced changes in cardiac contractility influenced not only the maximum excursion, but also the shape of the trajectory. Normal positive pressure ventilation displacing the heart in the thoracic cage was evident by the displacement of the reference point of the trajectory. CONCLUSIONS: The movement of the coronary artery after stabilization appears to be still significant. Minute characterization of the trajectory of motion could provide the substrate for achieving motion cancellation for existing robotic systems. Velocity plots could also help improve gated cardiac imaging.  相似文献   
34.
Amniotic membrane (AM), the most internal placental membrane, has unique properties including antiadhesive effects, bacteriostatic, wound protection and pain-reduction properties, as well as epithelialization initialization capacities. Furthermore, AM is widely available and less costly than other bioengineered skin substitutes. In a prospective pilot study, we evaluated the safety, feasibility, and the effects on healing of AM graft in 15 patients with chronic venous leg ulcers. AM grafts were prepared from placentas harvested during cesarean section. All grafted AM had adhered to the wound bed 7 days after being applied with a 100% engraftment rate. The percentage of granulation tissue increased significantly (from 17% on day 0 to 69% on day 14, p<0.0001), along with a significant decrease of fibrinous slough (from 36% at day 0 to 16% at day 14, p<0.001). A significant clinical response occurred in 12 patients (80%) including complete healing (20%) in three during the 3-month follow-up period. The ulcer surface area decreased significantly from a mean value (+/- standard deviation) of 4.59 +/- 2.49 cm(2) at baseline to 2.91+/-2.01 cm(2) on day 30 (p<0.001). All patients experienced a significant reduction of ulcer-related pain rapidly after AM transplantation. No adverse events were recorded. AM transplantation seems to function as a safe substrate, promoting proper epithelialization while suppressing excessive fibrosis. Further advantages of biotherapy with AM are its easy and low-cost production, and that it can be applied as an ambulatory treatment without immobilization. AM transplantation may thus be considered to be an alternative method for treating chronic leg ulcers.  相似文献   
35.
OBJECTIVE: Sleeve lobectomy is a widely accepted procedure for central tumors for which the alternative is pneumonectomy. The purpose of this study is to assess operative mortality, morbidity, and long-term results of sleeve lobectomies performed for non-small cell lung carcinoma (NSCLC). METHODS: A retrospective review of 218 patients who underwent sleeve lobectomy for NSCLC between 1981 and 2005 was undertaken. There were 186 (85%) men and 32 women with a mean age of 61.9 years (range, 19-82 years). Eighty patients (36.6%) had a preoperative contraindication to pneumonectomy. Right upper lobectomy was the most common operation (45.4%). Vascular sleeve resection was performed in 28 patients (12.8%) and was commonly associated with left upper lobectomy (n=20; 9.1%; p=0.0001). The histologic type was predominantly squamous cell carcinoma (n=164; 75%), followed by adenocarcinoma (n=46; 21%). Resection was incomplete in nine (4.1%) patients. RESULTS: There were nine operative deaths; the operative mortality and the morbidity rates were 4.1% and 22.9%, respectively. A total of 14 (6.4%) patients presented with bronchial anastomotic complications: two were fatal postoperatively, seven patients required reoperation, three required a stent insertion, and two were managed conservatively. Multivariate analysis showed that compromised patients (p=0.001), current smoking (p=0.01), right sided resections (p=0.003), bilobectomy (p=0.03), squamous cell carcinoma (p=0.03), and presence of N1 or N2 disease (p=0.01) were risk factors for mortality and morbidity. Follow-up was complete in 208 patients (95.4%). Overall 5-year and 10-year survival rates were 53% and 28.6%, respectively. After complete resection, recurrence was local in 10 patients, mediastinal in 20, and distant in 25. By multivariate analysis, two factors significantly and independently influenced survival: nodal status (N0-N1 vs N2; p=0.01) and the stage of the lung cancer (stage I-II vs III, p=0.02). CONCLUSIONS: For patients with NSCLC, sleeve lobectomy achieves local tumor control, even in patients with preoperative contraindication to pneumonectomy and is associated with low mortality and bronchial anastomotic complication rates. Postoperative complications are higher in compromised patients, smokers, N disease, right sided resections, bilobectomies, and squamous cell cancers. The presence of N2 disease and stage III significantly worsen the prognosis.  相似文献   
36.

Background  

Hip dislocation in children with cerebral palsy (CP) is a common and severe problem. The dislocation can be avoided, by screening and preventive treatment of children with hips at risk. The aim of this study was to analyse the characteristics of children with CP who develop hip displacement, in order to optimise a hip surveillance programme.  相似文献   
37.
38.
OBJECTIVE: The aim of this paper is to assess the accuracy of an algorithm implemented by PRAXIM in the SURGETICS navigation station for detection of the hip center. This study will assess the robustness and accuracy of the algorithm in various clinical situations such as those involving non-sphericity of the femoral head, motion of the pelvis during hip center detection, and restricted range of motion. MATERIALS AND METHODS: The localization of the hip center, based on kinematics, relies on the recording of n successive positions of the femoral rigid body in the localizer reference system during a passive circumduction motion of the hip joint. Therefore, the shape of the clouds of points acquired may vary from one acquisition to the next. To allow a comprehensive study of the consequences of these variations for hip center detection, we developed a simulator to generate numerous clouds of points. Results given subsequently for each test are the values of the difference between the femoral mechanical axis computed with C(c), the computed hip center, and the same axis computed with C(o), the reference hip center. RESULTS: Test 1: Sensitivity to noise. The errors ranged from 3.33 E - 12 (SD 3.29E - 12) for a noise of 0 mm to 8.18E - 1 (SD - 7.05E - 1) for a noise of 15 mm. Test 2: Sensitivity to the shape of the acquisition motion. All trajectories gave an error < 1 degrees . Test 3: Sensitivity to restricted range of motion. No value > 1 degrees was found during this test. Test 4: Sensitivity to the distance between two points of the cloud. No value > 0.5 degrees was found during this test. Test 5: Sensitivity to the number of points included in the cloud. No value > 1 degrees was found during this test. CONCLUSIONS: The Surgetics algorithm is robust to noise, can compensate for pelvic motion, and can be used even in the case of restricted range of motion.  相似文献   
39.
AIM: To evaluate in a prospective multicenter study the efficacy and safety of the suburethral support Uretex (Sofradim, Trevoux, France) delivered by a suprapubic approach in the treatment of female stress urinary incontinence. METHODS: Between March 2002 and March 2003, 57 patients were treated for stress urinary incontinence with Uretex. Preoperative evaluation included urodynamic examination and questionnaires (symptoms and quality of life, Contilife). Forty patients had pure stress urinary incontinence and 17 mixed urinary incontinence. No associated procedure was performed. The objective cure rate was evaluated by clinical examination and pad-test, and the subjective cure rate was assessed through questionnaires at 1, 3 and 12 months. RESULTS: The mean follow-up was 13 months (range 11-24 months). During follow up, chronic urinary retention requiring a tape section occurred in one patient, and in another patient a delay of vaginal healing was followed by a sling exposure and resection at 4 months. No infection or urethral erosion was reported. The objective cure rate was 96.2%, and the subjective cure rate was 79.2%; four patients reported low leakage on stress and nine patients complained of urge incontinence (four de novo and five persistent). CONCLUSION: The suprapubic Uretex Sup procedure is a safe and effective treatment for women with stress urinary incontinence.  相似文献   
40.
Work stress, burnout, and diminished empathy are prevalent issues for health‐care professionals. Mindfulness meditation (MM) is one commonly used strategy to manage stress. Measuring salivary cortisol allows for the assessment of serum cortisol level, a known stress level indicator. This study evaluated the association of subject‐reported stress symptoms and salivary cortisol in health‐care professionals, in an 8‐week MM program, with data collected prospectively at baseline and 8 weeks after program completion. Questionnaires [Profile of Mood States—Short Form (POMS‐SF), Maslach Burnout Inventory (MBI), and Interpersonal Reactivity Index (IRI)] measured mood, burnout and empathy. A paired t‐test between groups for pre/post‐salivary cortisol yielded no significant change. The POMS‐SF was most sensitive to change (mean increase 12.4; p = 0.020). Emotional exhaustion, measured in the MBI, was also affected by MM (mean decrease 4.54; p = 0.001). Changes in empathy may not have been captured due to either absence of effect of MM on empathy, subject number or scale sensitivity. Baseline and 8‐week correlations between salivary cortisol and survey results, and correlations between changes in these measures, were weak and not statistically significant. Nevertheless, psychometric results present a strong case for additional clinical trials of MM to reduce stress for health‐care professionals. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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