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141.
We evaluated changes in serum zinc (Zn) and copper (Cu) levels in two groups of children with chronic renal failure (CRF) – children with CRF who were on regular hemodialysis (Group 1, n=40) and children with CRF who were on conservative management (Group 2, n=31) – and in one group of healthy children (Group 3, n=30). All of the participants in the study were between 5–18 years old, and the composition of the three groups was almost identical with respect to age and sex. The length of time the children in Group 1 had been on hemodialysis varied between 3 and 52 months (mean: 20.97±14.8 months). To evaluate the impact of the duration of dialysis on serum levels of Zn, we further sub-divided Group 1 patients into two subgroups: Subgroup A patients (n=20) had been on hemodialysis therapy for less than 18 months (mean: 8.85±4.83 months); Subgroup B patients (n=20) had been on hemodialysis therapy for longer than 18 months (mean: 33.1±10.86 months). The PIXE (proton-induced X-ray emission) was used for measuring the trace elements. Results: The mean serum level of Zn was lower in the Group 1 (hemodialysis group) children than in the children of Group 2 (on conservative management) and group 3 (healthy children) (p<0.001), but the difference was not significant between Groups 2 and 3. No significant differences in serum levels of Cu were found among the three groups. The serum level of Zn was lower in Subgroup B than in Subgroup A (p<0.001). The correlation test showed that there was an inverse linear relation between the length of time the child was on the hemodialysis regimen and serum Zn levels. Conclusion: Chronic hemodialysis may lead to abnormalities in the serum levels of some trace elements in children with CRF that increase in severity with increasing duration of hemodialysis. Deficiencies of these trace elements – zinc in particular – may contribute to various conditions and symptoms in children undergoing chronic hemodialysis.  相似文献   
142.

Introduction

To evaluate temporal trends in the delivery and extent of lymphadenectomy (LND) in radical nephroureterectomy (RNU) performed in upper tract urothelial carcinoma (UTUC) patients.

Methods

We evaluated a multi institutional collaborative database composed by 1512 consecutive patients diagnosed with UTUC treated with RNU between 1990 and 2016. Year of surgery were grouped in five periods: 1990–1996, 1997–2002, 2003–2007, 2008–2012 and 2013–2016. Data about LND were available for all patients and numbers of nodes removed and positive were reported by dedicate uropathologists. The Mann–Whitney and Chi square tests were used to compare the statistical significance of differences in medians and proportions, respectively.

Results

Five hundred forty-five patients (36.0%) received a concomitant LND while 967 (64.0%) did not; 41.9% of open RNU patients received a concomitant LND compared to 24.4% of laparoscopic RNU patients. The rate of concomitant LND increased with time in the overall, laparoscopic and open RNU patients (all p?<?0.03). Patients treated with open RNU also had an increasing likelihood to receive an adequate concomitant LND (p?<?0.001) while those undergoing a laparoscopic approach did not (p?=?0.1). Patients treated with concomitant LND had a median longer operative time of 20 min (p?=?0.01). There were no differences in perioperative outcomes and complications between patients who received a concomitant LND and those who did not (p?>?0.1).

Conclusion

Although an increased trend was observed, most patients treated with RNU did not receive LND. Surgeons using a laparoscopic RNU were less likely to perform a concomitant LND, and when done, they remove less nodes.
  相似文献   
143.

Objective

To evaluate incidence and predictors of local failure (LF) after radical cystectomy (RC) due to bladder cancer.

Methods

We focused on 1,112 patients treated with RC, between 1990 and 2012, at a single center. LF was defined as imaging evidence of recurrence in the pelvic soft tissues or nodes below the aortic bifurcation at least 3 months before the detection of distant metastases. Competing risk analyses tested the relationship between clinical and pathological factors and the risk to develop LF. Regression tree analysis stratified patients into risk-groups based on their characteristics and the corresponding LF rate.

Results

Overall, 50 (4.5%) patients developed LF during a median follow-up period of 62 (35–92) months. On univariable competing risk regression analyses, pathological T stage (pT4 vs. pT3; hazard ratio [HR] = 2.55, P = 0.003), soft tissue surgical margin (STSM; HR = 2.95, P = 0.005), and variant histology (HR = 1.79, P = 0.03) were associated with an increased risk of developing LF. The cohort was stratified into 4 risk groups: very low (≤pT3a disease and pure urothelial histology), low (≤pT3a disease and variant histology), intermediate (pT4 disease), and high (positive STSM).

Conclusions

LF is an important event in RC patients. We developed a new risk model based on bladder cancer characteristics. Our findings could help with the identification of the best candidate for consideration of adjuvant radiotherapy.  相似文献   
144.

Purpose

To evaluate the effect of preoperative anemia (PA) on oncological outcomes in a multicenter cohort of patients with non–muscle-invasive bladder cancer (NMIBC) treated with transurethral resection of the bladder (TURB) and adjuvant intravesical therapies. We hypothesize that PA represents a marker of disease aggressiveness and could be used to improve the discrimination of prognostic tools for the prediction of disease recurrence and progression.

Methods

This multicenter retrospective study included 1,117 patients from 4 different centers. The presence of PA was assessed according to the World Health Organization classification as a preoperative hemoglobin level of≤13 g/dl in men and≤12 g/dl in women. PA evaluation was done at each institution, generally 1 to 3 days before surgery. Multivariable Cox regression models were performed to evaluate the prognostic effect of PA on survival outcomes.

Results

Overall, 381 (34%) patients with NMIBC treated with TURB, had PA. Median follow-up for patients alive at last follow-up was 62.7 months (interquartile range: 25–110.7). On multivariable Cox regression analyses that accounted for the effect of standard clinicopathologic prognosticators, PA was independently associated with recurrence-free survival (P = 0.045) and progression-free survival (P = 0.01). Adding PA to a model for the prediction of disease recurrence and progression improved the discrimination of the prognostic models marginally from 69.8% to 70.3% and from 71.6% to 73.1%, respectively.

Conclusions

PA was found in more than one-third of patients with NMIBC treated with TURB. PA was associated with poor oncological outcomes and was an independent predictor of intravesical disease recurrence and progression. However, the additional prognostic information provided by PA remains limited.  相似文献   
145.

Background Context

Metastatic spine tumor surgery (MSTS) is associated with substantial blood loss, therefore leading to high morbidity and mortality. Although intraoperative cell salvage with leukocyte depletion filter (IOCS-LDF) has been studied as an effective means of reducing blood loss in other surgical settings, including the spine, no study has yet analyzed the efficacy of reinfusion of salvaged blood in reducing the need for allogenic blood transfusion in patients who have had surgery for MSTS.

Purpose

This study aimed to analyze the efficacy, safety, and cost-effectiveness of using IOCS-LDF in MSTS.

Study Design

This is a retrospective controlled study.

Patient Sample

A total of 176 patients undergoing MSTS were included in the study.

Methods

All patients undergoing MSTS at a single center between February 2010 and December 2014 were included in the study. The primary outcome measure was the use of autologous blood transfusion. Secondary outcome measures included hospital stay, survival time, complications, and procedural costs. The key predictor variable was whether IOCS-LDF was used during surgery. Logistic and linear regression analyses were conducted by controlling variables such as tumor type, number of diseased vertebrae, approach, number and site of stabilized segments, operation time, preoperative anemia, American Society of Anesthesiologists (ASA) grade, age, gender, and body mass index (BMI). No funding was obtained and there are no conflicts of interest to be declared.

Results

Data included 63 cases (IOCS-LDF) and 113 controls (non–IOCS-LDF). Intraoperative cell salvage with LDF utilization was substantively and significantly associated with a lower likelihood of allogenic blood transfusion (OR=0.407, p=.03). Intraoperative cell salvage with LDF was cost neutral (p=.88). Average hospital stay was 3.76 days shorter among IOCS-LDF patients (p=.03). Patient survival and complication rates were comparable in both groups.

Conclusions

We have demonstrated that the use of IOCS-LDF in MSTS reduces the need for postoperative allogenic blood transfusion while maintaining satisfactory postoperative hemoglobin. We recommend routine use of IOCS-LDF in MSTS for its safety, efficacy, and potential cost benefit.  相似文献   
146.

Objective

Patients with end-stage renal disease have multiple comorbidities and are at increased risk for postoperative complications and resource utilization. Our goal was to determine the rate and causes of 30-day and 90-day hospital readmissions after the creation of outpatient hemodialysis access.

Methods

We retrospectively reviewed all outpatient upper extremity hemodialysis access creations performed at our medical center from 2008 to 2015. Readmission was defined as any inpatient status admission ≤30 and 90 days. Reasons for such admissions were analyzed, and multivariate analyses assessed risk factors.

Results

We identified 537 patients (60% male). Average age was 59 years. Access type included radiocephalic (4.5%), brachiocephalic (50.7%), brachiobasilic (22.5%), and prosthetic (20%) arteriovenous fistulas. The 90-day mortality rate was 0.7%. Postoperative hospital readmission rates were 25.5% at 30 days and 47.7% at 90 days. Reasons for admission were access related in 10.9% and dialysis catheter related in 6.9%. Other reasons for admission included shortness of breath/volume overload (15.8%), gastrointestinal (11.9%), cardiac/chest pain (10.9%), unrelated infectious causes (11.9%), failure to thrive (5%), altered mental status (4%), electrolyte abnormalities (3%), and musculoskeletal (2.5%). Preoperative predictors of all cause 30-day readmission included dementia (odds ratio [OR], 5.76; 95% confidence interval [CI], 1.34-24.8; P = .018), hypertension (OR, 3.92; 95% CI, 1.07-14.4; P = .039), chronic obstructive pulmonary disease (OR, 2.19; 95% CI, 1.01-4.76; P = .046), and current smoking (OR, 2.14; 95% CI, 1.32-3.47; P = .002). Predictors of all cause 90-day readmission were hepatic insufficiency (OR, 6.08; 95% CI, 1.2-30.8; P = .029), hypertension (OR, 3.43; 95% CI, 1.36-8.65; P = .009), black race (OR, 2.47; 95% CI, 1.48-4.14; P = .001), Hispanic ethnicity (OR, 2.04; 95% CI, 1.01-4.11; P = .046), and obesity (OR, 1.5; 95% CI, 1.02-2.19; P = .039). Predictors of 90-day access-related readmission included chronic obstructive pulmonary disease (OR, 5.27; 95% CI, 1.38-20.0; P = .015), previous stroke (OR, 3.76; 95% CI, 1.5-9.4; P = .005), being on dialysis at time of the operation (OR, 2.8; 95% CI, 1.17-6.84; P = .022), and prosthetic graft placement (OR, 2.86; 95% CI, 1.07-7.6; P = .036). An additional 9.7% had at least one emergency department presentation ≤90 days but were not admitted.

Conclusions

Patients undergoing placement of hemodialysis access are at high risk for readmission mostly from causes unrelated to their operation. This has an effect for global care for these patients as well as care of these patients in accountable care organizations.  相似文献   
147.
Pulmonary arterial embolic disease of donor lungs is a known entity. Its implications on the technicality, the perioperative management, and the outcome of lung transplantation depend on the extent of the embolic disease and the indicators of lung function at the time of procurement. We report a case of lung transplantation from a donor who was known to have significant acute pulmonary embolic disease and the perioperative management used to optimize the outcome.  相似文献   
148.
149.
BACKGROUND AND OBJECTIVES: Successful laser treatment of cutaneous hyper-vascular lesions requires appropriate laser irradiation parameters for selective photothermolysis of ectatic dermal blood vessels as well as appropriate cooling parameters for epidermal protection based on an individual patient basis. Using the rabbit ear as an in vivo model for dermal vasculature, we investigated the influences of laser wavelength (585 nm vs. 595 nm) and cryogen spray cooling with various spurt durations on the laser-induced thermal injury to dermal blood vessels. Wound healing response was also evaluated in 2 hours and 4 days. STUDY DESIGN/MATERIALS AND METHODS: Flashlamp-pumped pulsed dye laser ScleroPlus (operated at the wavelength of 585 or 595 nm) was used for the comparison between the influences of two wavelengths (585 nm vs. 595 nm). R134-a cryogen spurts with the durations from 50 to 300 milliseconds were sprayed onto the sites to be irradiated and terminated 20 milliseconds before the onset of the laser pulses. In vivo rabbit ear was used as the model for cutaneous hyper-vascular lesions. Totally 10 New Zealand Albino white rabbits were experimented and in each rabbit ear six to seven sites were irradiated. Five animals were sacrificed 2 hours after the irradiation, and the remaining five sacrificed 4 days after the irradiation. Thermal injury to the blood vessel was assessed by hematoxylin and eosin stained histological sections and confirmed by an apoptosis assay. RESULTS: When the radiant exposures were above 10 J/cm2, 595 nm wavelength induced equivalent or more severe thermal injury to dermal blood vessels than 585 nm. Cryogen spray cooling with the spurt durations above 100 milliseconds resulted in increased depth of the most superficial thermal injury to dermal blood vessels than without cooling, indicating that superficial blood vessels were non-specifically cooled by the cryogen spurts applied at these parameters. Laser-induced thermal injury was significantly healed in the rabbit ear vasculature at 4 days post irradiation. CONCLUSIONS: Given sufficient radiant exposure, 595 nm wavelength can induce equivalent or more severe vascular injury compared with 585 nm. Cryogen spray cooling with the spurt durations above 100 ms may impair the photocoagulation of superficial blood vessels. Irreversible thermal injury to blood vessel can be achieved only when the basement membrane of blood vessel wall is irreversibly damaged.  相似文献   
150.
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