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111.
The process of collecting and analyzing transplant data is complex. Familiarity with how these data are collected is crucial to a thorough understanding of the information. This article focuses on available OPTN-SRTR data and the continuing evolution of data collection mechanisms; how that data collection system is improving the data quality and reducing the data collection burden; how additional ascertainment of outcomes both completes and validates existing data; and caveats that remain for researchers. This year's article focuses further on research considerations related to cohort choice, timing of data submission, and potential biases in follow-up data. Ongoing improvements in data collection timeliness and scope are covered. The impact of extra ascertainment of outcomes, particularly for post-transplant kidney graft failure from Medicare data, are also examined. A section on graft failure reporting among different sources traces the steps by which the SRTR reconciles different data sources in its analyses. It is important that those reading and conducting transplant research understand the origin, structure, and scope of the available data. All of these issues should be carefully considered when choosing cohorts and data sources for analysis.  相似文献   
112.
Transilluminated powered phlebectomy (TIPP) is a promising alternative to traditional ambulatory phlebectomy procedures. This retrospective review of 339 patients represents the senior author's first consecutive series of 400 cases performed using TIPP for the treatment of varicose veins in a 6-year period. Patients were followed for 12 weeks postoperatively. Data analyzed included operative time, intraoperative complications, stab incision ranges, postoperative complications, and patient satisfaction. The mean operative time was 19.7 minutes, and 246 (61.5%) cases involved 10 to 20 incisions. Postoperative complications included an episode of symptomatic deep vein thrombosis in one (0.3%) patient, excessive or hypertrophic scarring in two (0.6%) patients, discoloration of the lower extremity skin due to hemosiderin staining in eight (2.3%) patients, and cellulitis in one (0.3%) patient. No recurrences were observed at a follow-up of 12 weeks. Three hundred thirty-eight (99.7%) patients reported good outcomes and were satisfied with the procedure. This review by an individual surgeon is beneficial in analyzing the outcomes and complications associated with TIPP, as a standard protocol was followed and an adequate volume was performed to advance past the learning curve associated with the technique. When concomitant saphenous vein incompetence is present, staged treatment of varicosities with TIPP after endovenous laser ablation is recommended. With proper training and experience, utilization of TIPP with a lower oscillation frequency and secondary tumescence results in good outcome and high patient satisfaction.  相似文献   
113.
Although relatively uncommon, upper extremity arterial injuries are serious and may significantly impact the outcome of the trauma patient. Management of upper extremity arterial injuries at an urban level I trauma center was reviewed to determine incidence, assess the current management strategy, and evaluate hospital outcome. Upper extremity trauma patients with arterial injury who presented between January 2005 and December 2006 were included in this retrospective review. Data collected included age, gender, race, mechanism of injury, type of injury, associated upper extremity injuries, concomitant injuries, injury severity score (ISS), diagnostic modalities employed, surgical procedures and interventions, mortality, length of stay, and discharge disposition. Statistical analysis between blunt and penetrating arterial injuries as well as between proximal and distal arterial injuries also was conducted. During a 2-year period, 28 patients with 30 upper extremity arterial injuries were admitted, yielding an incidence of 0.48%. The study population was comprised primarily of young Caucasian males, with a mean ISS of 9.0. The majority (89.3%) of patients suffered concomitant upper extremity injuries. Twenty-two nerve injuries were identified in 16 (57.1%) patients. The most common injury mechanism was cut by glass (39.3%). Arterial injuries were categorized into 18 (60.0%) penetrating and 12 (40.0%) blunt injuries. Involved artery distribution was as follows: 12 (40.0%) brachial, eight (26.7%) ulnar, seven (23.3%) radial, and three (10.0%) axillary. Over half (56.7%) of the injuries resulted from lacerations. Injuries were managed as follows: 14 (46.7%) primary repairs, eight (26.7%) ligations, six (20.0%) saphenous vein graft bypasses, and two (6.7%) endovascular procedures. Eleven (39.3%) patients required intensive care unit (ICU) admission. The overall mean length of hospitalization for these patients was 7.4 days compared to a mean length of hospitalization of 2.0 days for the 17 (44.7%) patients who did not require ICU admission. The overall limb salvage rate was 96.4% as arterial injuries were successfully repaired in 27 of 28 patients. No patients expired and all were discharged home. Equivalent demographics, mechanisms of injury, surgical management approaches, and successful hospital outcomes were demonstrated between penetrating and blunt injuries as well as between proximal and distal arterial injuries. The current management approach, including use of angiography and prompt surgical management, results in successful outcomes after upper extremity arterial injuries and will continue to be utilized.  相似文献   
114.
Background contextPatients with back dominant pain generally have a worse prognosis after spine surgery when compared with patients with leg dominant pain. Despite the importance of determining whether patients with lumbar spine pain have back or leg dominant pain as a predictor for success after decompression surgery, there are limited data on the reliability of methods for doing so.PurposeTo assess the test-retest reliability of a patient's ability to describe whether their lumbar spine pain is leg or back dominant using standardized questions.Study design/settingProspective, blinded, test-retest cohort study performed in an academic spinal surgery clinic.Patient sampleConsecutive patients presenting for consultation to one of three spinal surgeons for lumbar spine pain were enrolled.Outcome measuresEight questions to ascertain a patient's dominant location of pain, either back dominant or leg dominant, were identified from the literature and local experts.MethodsThese eight questions were administered in a test-retest format over two weeks. The test-retest reliability of these questions were assessed in a self-administered questionnaire format for one group of patients and by a trained interviewer in a second group.ResultsThe test-retest reliability of each question ranged from substantial (eg, interviewer-administered percent question, weighted kappa=0.77) to slight (eg, self-administered pain diagram, weighted kappa=0.09). The Percent question was the most reliable in both groups (self-administered, interviewer). All questions in the interviewer-administered group were significantly (p<.001) more reliable than the self-administered group. Depending on the question, between 0% and 32% of patients provided a completely opposite response on test-retest. There was variability in prevalence of leg dominant pain, depending on which question was asked and there was no single question that identified all patients with leg dominant pain.ConclusionA patient's ability to identify whether his or her lumbar spine pain is leg or back dominant may be unreliable and depends on which questions are asked, and also how they are asked. The Percent question is the most reliable method to determine the dominant location of pain. However, given the variability of responses and the generally poorer reliability of many specific questions, it is recommended that multiple methods be used to assess a patient's dominant location of pain.  相似文献   
115.
The production of inflammatory mediators by abdominal adipose tissue may link obesity and insulin resistance. We determined the influence of systemic levels of interleukin-6 and C-reactive protein on insulin sensitivity after weight loss via Roux-en-Y gastric bypass surgery. Severely obese individuals (n 5 15) were evaluated at baseline and at 6 months after surgery. Insulin sensitivity was determined by frequently sampled intravenous glucose tolerance testing at the same time points. Visceral and subcutaneous adipose tissue volumes were quantified by computed tomography. Interleukin-6 and C-reactive protein were measured by enzyme-linked immunoassay in plasma and in adipose tissue biopsies. Correlation analysis was used to determine associations between insulin sensitivity and other outcome variables. Significance was set at P < 0.05. Plasma interleukin-6 concentrations were significantly correlated to the IL-6 content of subcutaneous adipose tissue (r = 0.71). At 6 months postsurgery, subcutaneous and visceral adipose tissue volumes were significantly reduced (34.7% and 44.1%, respectively) and insulin sensitivity had improved by 160.9%. Significant longitudinal correlations were found between insulin sensitivity and plasma C-reactive protein (r = 20.61), but not plasma interleukin-6 at 6 months. These findings offer insights that link obesity and insulin resistance via the activity of inflammatory mediators. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation). Supported by National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases 1R03 DK067167-01A1 (N.G.), the Emory University Research Committee Grant (N.G.), and the National Institutes of Health/National Center for Research Resources General Clinical Research Center Grant M01 RR00039 (N.G., E.L.).  相似文献   
116.
We integrated the US transplant registry with administrative records from an academic hospital consortium (97 centers, 2008–2012) to identify predonation comorbidity and perioperative complications captured in diagnostic, procedure, and registry sources. Correlates (adjusted odds ratio, aOR) of perioperative complications were examined with multivariate logistic regression. Among 14 964 living kidney donors, 11.6% were African American. Nephrectomies were predominantly laparoscopic (93.8%); 2.4% were robotic and 3.7% were planned open procedures. Overall, 16.8% of donors experienced a perioperative complication, most commonly gastrointestinal (4.4%), bleeding (3.0%), respiratory (2.5%), surgical/anesthesia‐related injuries (2.4%), and “other” complications (6.6%). Major Clavien Classification of Surgical Complications grade IV or higher affected 2.5% of donors. After adjustment for demographic, clinical (including comorbidities), procedure, and center factors, African Americans had increased risk of any complication (aOR 1.26, p = 0.001) and of Clavien grade II or higher (aOR 1.39, p = 0.0002), grade III or higher (aOR 1.56, p < 0.0001), and grade IV or higher (aOR 1.56, p = 0.004) events. Other significant correlates of Clavien grade IV or higher events included obesity (aOR 1.55, p = 0.0005), predonation hematologic (aOR 2.78, p = 0.0002) and psychiatric (aOR 1.45, p = 0.04) conditions, and robotic nephrectomy (aOR 2.07, p = 0.002), while annual center volume >50 (aOR 0.55, p < 0.0001) was associated with lower risk. Complications after live donor nephrectomy vary with baseline demographic, clinical, procedure, and center factors, but the most serious complications are infrequent. Future work should examine underlying mechanisms and approaches to minimizing the risk of perioperative complications in all donors.  相似文献   
117.
BACKGROUND: Recipients of hearts from donors with spontaneous intracerebral hemorrhage (ICH) are at increased risk of allograft vasculopathy compared with trauma donors. We have recently shown that the vitronectin receptor (integrin alpha(V)beta3) is upregulated in transplant vasculopathy. We hypothesized that donor ICH is associated with systemic activation of alpha(V)beta3 in the donor before transplantation. METHODS: We evaluated mRNA expressions of alpha(V)beta3 (TaqMan PCR) in endomyocardial biopsy samples at 1-week post-transplant in 20 recipients from ICH donors and 20 recipients from trauma donors. To investigate whether systemic activation of alpha(V)beta3 was present in the donor before transplantation, alpha(V)beta3 expression was also evaluated in the corresponding donor spleen lymphocytes. All patients underwent serial coronary intravascular ultrasound to evaluate for coronary vasculopathy. The baseline characteristics were similar except for increased donor age in the ICH Group. RESULTS: The ICH Group showed significant increased mRNA expression of alpha(V)beta3 in the heart biopsy samples (3.8-fold, p = 0.012) and in the corresponding donor spleen lymphocytes (3.5-fold, p = 0.014) compared with the Trauma Group. At 1 year, the ICH Group also showed increased progression of coronary vasculopathy. Multivariate regression analysis found that donor lymphocytic alpha(V)beta3 mRNA expression was independently associated with increased risk of vasculopathy (odds ratio, 1.9; 95% CI, 1.21-3.98, p = 0.03). CONCLUSIONS: Our report demonstrates the presence of systemic activation of alpha(V)beta3 in donors with spontaneous intracerebral hemorrhage and its association with the subsequent development of allograft vasculopathy in the recipient.  相似文献   
118.
BACKGROUND: Hypertension is a potential risk factor for allograft coronary vasculopathy. We evaluated the efficacy of angiotensin-converting enzyme (ACE) inhibitors and calcium antagonists, and their combined use, on the development of coronary vasculopathy in hypertensive heart transplant recipients. METHODS: Eighty-two heart transplant recipients underwent serial intravascular ultrasound (IVUS) analysis at baseline (within 1 month) and at 1 year after transplantation and were evaluated for the development of coronary vasculopathy. Patients were divided into 4 groups. Nineteen normotensive recipients received no treatment, control (Group A). Hypertensive patients were treated with either ACE inhibitors (Group B, n = 37), calcium antagonists (Group C, n = 16), or both (Group D, n = 10). RESULTS: We found a significant reduction in IVUS indices of coronary vasculopathy in heart transplant recipients who used a combination of an ACE inhibitor and a calcium antagonist compared with recipients who used either drug alone (p < 0.05). This synergistic efficacy was independent of the baseline indices evaluated in a multivariate regression analysis model and was noted despite comparable mean arterial pressure among the 3 hypertensive groups at 1 year, thus suggesting the presence of a synergistic anti-proliferative effect beyond the anti-hypertensive efficacy. CONCLUSIONS: The combined use of an ACE inhibitor and a calcium antagonist is more effective than the individual use of either drug alone on the development of coronary vasculopathy in cardiac transplant recipients. Large randomized clinical trials are warranted to evaluate such a synergistic efficacy.  相似文献   
119.
OBJECTIVE: The indications for aortic root replacement in acute type A dissection are unclear. We reviewed the immediate and long-term outcome of consecutive patients in a series in which a low-threshold policy of composite aortic root replacement had evolved. METHODS: From a prospectively compiled aortic surgery database, we identified 162 patients who had either supracoronary interposition grafting, Group A (n=89), or composite root replacement, Group B (n=73) for acute type A dissection. Patients receiving total arch replacements were excluded. Operative and clinical details were analyzed and patient survival was compared to an age and gender matched census cohort. Need for reoperation on the proximal or distal aorta was also noted. Follow-up totaled 795.5 patient-years. RESULTS: Hospital mortality rates were identical in both groups (12.3%: 11 deaths in group A; 9 in group B). Chronic pulmonary disease, diabetes, malperfusion, hemodynamic compromise and aortic root dilatation were independent risk factors for hospital death. Actuarial survival estimates at 1, 5 and 10 years were 79% (71-88%), 64% (53-75%), and 55% (41-68%) for group A, and 79% (70-86%), 73% (62-83%), and 65% (52-78%) for group B (P=0.48). Age and operative patency of the ascending false lumen were independent risk factors for death after hospital discharge. Proximal aortic reoperation was required for four patients in group A and none in group B (P=0.085). CONCLUSION: A strategy of replacement rather than repair of the dissected aortic root for specific indications in type A dissection yielded high survival and low proximal reoperation rates. These results support an aggressive policy of composite root replacement in acute type A dissection.  相似文献   
120.
BACKGROUND: Cutaneous cancers exhibit a much higher incidence in patients with chronic lymphocytic leukemia than in nonleukemic patients. Squamous and basal cell carcinomas also exhibit greater subclinical tumor extension in patients with chronic lymphocytic leukemia. OBJECTIVE: The purpose of this study was to estimate and compare the recurrence rates of squamous cell carcinoma after Mohs' surgery in patients with chronic lymphocytic leukemia compared with those in controls and to evaluate differences among squamous cell carcinoma size and histologic grade. METHODS: We retrospectively assessed the clinical histories, postoperative notes, and surgical photographs of patients with chronic lymphocytic leukemia and controls matched (2:1) for age, sex, and surgical year. Both patients and controls underwent Mohs' surgery for squamous cell carcinoma of the head and neck at the Mayo Clinic between March 1988 and April 1999. RESULTS: Twenty-eight patients who underwent Mohs' surgery for 57 squamous cell carcinomas had 7 recurrences. The cumulative incidence of recurrence on a per-tumor basis was 4.3% at 1 year, 14.8% at 3 years, and 19.0% at 5 years. Squamous cell carcinoma was seven times more likely to recur in patients with chronic lymphocytic leukemia than in controls (p = .003). The distribution of tumor histologic grade was not significantly different between patients and controls (p = .39). Maximum preoperative tumor diameters were clinically similar between patients and controls (median 15 mm vs 14 mm; p = .04). CONCLUSION: The recurrence rates of squamous cell carcinoma were significantly higher in patients with chronic lymphocytic leukemia. Squamous cell carcinomas in patients with chronic lymphocytic leukemia did not exhibit a significant difference in histologic grade or clinical difference in preoperative tumor size. Close surveillance for squamous cell carcinoma recurrence is warranted in patients with chronic lymphocytic leukemia.  相似文献   
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