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Background

The use of partial nephrectomy (PN) to treat renal cell carcinoma has grown to include larger, more complex tumors. Such tumors are more likely to be up-staged to pT3a and generate controversy regarding the oncologic safety of PN. We aimed to estimate the proportion of patients up-staged to T3a disease after PN, stratified by clinical stage, and characterize their survival.

Methods

From 1998 to 2013, pT1-pT3aN0M0 kidney cancer patients undergoing PN or radical nephrectomy (RN) were identified from the Surveillance Epidemiology and End Results registries. Cox proportional hazards models compared cancer-specific (CSS) and overall survival (OS) for PN patients with pT1a, pT1b, and pT2 disease to stratified, up-staged pT3a patients undergoing PN. Also, we compared PN patients with up-staged pT3a disease to RN patients with pT3a disease.

Results

From the 28,854 patients undergoing PN, the estimated proportion up-staged to pT3a was 4.2%, 9.5%, and 19.5% for cT1a, cT1b, and cT2, respectively. OS was worse for tumors up-staged from cT1a to pT3a, but not for cT1b or cT2 tumors. Up-staged pT3a tumors across all stage strata demonstrated worse CSS, with worse survival for larger tumors. Analysis revealed no difference in OS or CSS for up-staged pT3a PN patients compared to pT3a RN patients.

Conclusions

A greater proportion of patients experience T3a up-staging after PN with increasing initial T stage. Up-staged pT3a patients have worse CSS across all clinical tumor stages after PN. However, our results do not demonstrate that patients up-staged after PN have compromised oncologic outcomes compared to all-comers with pT3a disease receiving RN.  相似文献   
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Background

As the vertical sleeve gastrectomy (VSG) becomes increasingly popular, its effect on postoperative micronutrient levels, such as thiamine, becomes more important. We previously found a 1.8% prevalence of thiamine deficiency in bariatric patients before surgery.

Objective

The aims of this study were to determine the prevalence of thiamine deficiency at our center after VSG and to explore possible predictors of postoperative thiamine levels.

Setting

University hospital, United States.

Methods

A retrospective chart review was performed on 147 bariatric patients between 18- and 65-years old who underwent VSG between April 2011 and February 2015. Demographic characteristics, preoperative body mass index (BMI), obesity-associated co-morbidities, alcohol intake, smoking habits, insurance type, calendar year of the procedure, occurrence of postoperative complications, and compliance with postoperative nutrition and follow-up appointment guidelines were extracted from clinical charts. We defined thiamine deficiency as<78 nM on any lab draw within 1 year after the VSG. The χ2, Fisher exact, and Mann-Whitney U tests, and multivariate logistic regression models were created to analyze the association of the above factors with thiamine deficiency after a VSG.

Results

Of 147 patients, 105 met inclusion criteria and were analyzed, of whom 27 (25.7%) had thiamine deficiency. Overall median age was 42 years (interquartile ratio: 36, 49). The majority of patients were either African Americans or Caucasian (47.6% and 44.8%, respectively), female (77.1%), and compliant with vitamins (81.0%). The overall mean preoperative BMI was 46.4 kg/m2. Patients with thiamine deficiency were more likely to be African American (66.7%, P = .024), have a larger preoperative BMI (P = .026), and to report repetitive episodes of nausea (59.3%, P = .002) and vomiting (44.4%, P = .001) at any of their postoperative appointments within 1 year after surgery. Compliance with vitamins did not differ between those with or without thiamine deficiency (70.4%, 84.6%, P = .10). After controlling for all factors, African American race (odds ratio [OR] 3.9, P = .019), higher preoperative BMI (OR 1.13, P = .001), nausea (OR 3.81, P = .02), and vomiting (OR 3.49, P = .032) were independent risk factors for the development of thiamine deficiency.

Conclusions

We found an alarmingly high prevalence of thiamine deficiency in postoperative SG patients. This disorder may have serious consequences including Wernicke encephalopathy; hence, it is important to identify predictive demographic, postoperative, and behavioral factors so that appropriate measures can be taken to prevent thiamine deficiency in VSG patients.  相似文献   
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Background

Peripheral nerve blockade is used to provide analgesia for patients undergoing total knee arthroplasty. This study compared a single-injection adductor canal block (SACB) with adjuvants to continuous adductor canal blockade (CACB). The hypothesis was that the 2 groups would have equivalent analgesia at 30 hours after neural blockade.

Methods

This was a double-blinded, randomized, controlled, equivalency trial. Sixty patients were randomized to either the SACB group (20 mL of 0.25% bupivacaine, 1.67 mcg/mL of clonidine, 2 mg of dexamethasone, 150 mcg of buprenorphine, and 2.5 mcg/mL of epinephrine) or the CACB group (20 mL 0.25% of bupivacaine injection with 2.5 mcg/mL of epinephrine followed by an 8 mL/h infusion of 0.125% bupivacaine continued through postoperative day 2). The primary outcome was movement pain scores at 30 hours using the numeric rating scale (NRS). The secondary outcomes included serial postoperative NRS pain scores (rest and movement every 6 hours), opioid consumption, time to first opioid administration, ability to straight leg raise, patient satisfaction, length of stay, and the incidence of nausea/vomiting.

Results

An intention-to-treat analysis included 59 patients. The NRS pain scores with movement were equivalent at 30 hours (SACB 5.5 ± 2.8 vs CACB 5.7 ± 2.9 [mean NRS ± standard deviation]; mean difference 0.2 [?1.5 to 1.0 {90% confidence interval}]). All NRS pain scores were equivalent until 42 hours (rest) and 48 hours (rest and movement) with the CACB group having lower pain scores. Other secondary outcomes were not statistically different.

Conclusion

An SACB provides equivalent analgesia for up to 36 hours after block placement when compared with a CACB for patients undergoing total knee arthroplasty, though a CACB was favored at 42 hours and beyond.  相似文献   
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Cystic Fibrosis (CF) patient registries are valuable data sources for researchers studying the natural history, treatment paradigms, and long‐term health outcomes of individuals with CF. In this review, we discuss the role of CF patient registries in facilitating comparative effectiveness research, particularly evaluating therapies and variation in health care delivery. We also discuss the limitations of registry‐based research, particularly indication bias, as well as statistical methods that can be used to address these issues.  相似文献   
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