Venous Access: National Guideline and Registry Development (VANGUARD): Advancing Patient-Centered Venous Access Care Through the Development of a National Coordinated Registry Network.

There are over 8 million central venous access devices inserted each year, many in patients with chronic conditions who rely on central access for life-preserving therapies. Central venous access device-related complications can be life-threatening and add tens of billions of dollars to health care costs, while their incidence is most likely grossly mis- or underreported by medical institutions. In this communication, we review the challenges that impair retention, exchange, and analysis of data necessary for a meaningful understanding of critical events and outcomes in this clinical domain. The difficulty is not only with data extraction and harmonization from electronic health records, national surveillance systems, or other health information repositories where data might be stored. The problem is that reliable and appropriate data are not recorded, or falsely recorded, at least in part because policy, payment, penalties, proprietary concerns, and workflow burdens discourage completeness and accuracy. We provide a roadmap for the development of health care information systems and infrastructure that address these challenges, framed within the context of research studies that build a framework of standardized terminology, decision support, data capture, and information exchange necessary for the task. This roadmap is embedded in a broader Coordinated Registry Network Learning Community, and facilitated by the Medical Device Epidemiology Network, a Public-Private Partnership sponsored by the US Food and Drug Administration, with the scope of advancing methods, national and international infrastructure, and partnerships needed for the evaluation of medical devices throughout their total life cycle.

Stimulating Patient Engagement in Medical Device Development in Kidney Disease: A Report of a Kidney Health Initiative Workshop.

New technologies challenge current dialysis treatment paradigms as devices become smaller, more portable, and increasingly used outside the dialysis clinic. It is unclear how patients will view this care transition, and it will be important to consider patient and care partner perspectives during all aspects of development for novel dialysis therapies, from design and clinical trials to regulatory approval. To gain insight into this area, the Kidney Health Initiative, a public-private partnership between the American Society of Nephrology, the US Food and Drug Administration, and nearly 80 member organizations and companies dedicated to enhancing patient safety and fostering innovation in kidney disease, convened a workshop of patients, care partners, and other kidney community stakeholders. The workshop included background presentations followed by focused small group discussions in 3 areas (device design, clinical trials, and regulatory approval). Participants explored how to involve patients throughout the life cycle of a medical device, including discussions of how patients can influence device design, assist in the planning and implementation of clinical trials, and provide input to affect regulatory decisions. Patients were engaged in the workshop discussion and interested in sharing their perspectives, but they recommended additional efforts around education, communication, and outreach in these areas.

Impact of Poverty and Health Care Insurance on Arteriovenous Fistula Use among Incident Hemodialysis Patients.

BACKGROUND: The impact of socioeconomic factors on arteriovenous fistula (AVF) creation in hemodialysis (HD) patients is not well understood. We assessed the association of area and individual-level indicators of poverty and health care insurance on AVF use among incident end-stage renal disease (ESRD) patients initiated on HD. METHODS: In this retrospective cohort study using the United States Renal Data System database, we identified 669,206 patients initiated on maintenance HD from January 1, 2007 through December 31, 2012. We assessed the Medicare-Medicaid dual-eligibility status as an indicator of individual-level poverty and ZIP code-level median household income (MHI) data obtained from the 2010 United States Census. We conducted logistic regression of AVF use at start of dialysis as the outcome variable. RESULTS: The proportions of dual-eligible and non-dual-eligible patients who initiated HD with an AVF were 12.53 and 16.17%, respectively (p<0.001). Dual eligibility was associated with significantly lower likelihood of AVF use upon initiation of HD (adjusted odds ratio (aOR) 0.91; 95% CI 0.90-0.93). Patients in the lowest area-level MHI quintile had an aOR of 0.97 (95% CI 0.95-0.99) compared to those in higher quintile levels. However, dual eligibility and area-level MHI were not significant in patients with Veterans Affairs (VA) coverage. CONCLUSIONS: Individual- and area-level measures of poverty were independently associated with a lower likelihood of AVF use at the start of HD, the only exception being patients with VA health care benefits. Efforts to improve incident AVF use may require focusing on pre-ESRD care to be successful.

Practice patterns in evaluation of living kidney donors in United Network for Organ Sharing-approved kidney transplant centers.

INTRODUCTION: The current pattern of evaluation for living kidney donors was investigated. METHODS: We designed a 37-question electronic survey to collect information about living kidney donor evaluation. Of the 181 United Network for Organ Sharing (UNOS)-approved centers, 72 responded. Survey responses were coded and downloaded into SPSS. Data was expressed as means and standard deviations or the percentage of centers with specific responses. RESULTS: 66% of the centers used a cut-off of <80 ml/min for exclusion of living kidney donors. 24-hour urine measuring creatinine clearance (CrCl) was the most common screening method for glomerular filtration rate (GFR) assessment in potential living donors. 56% of the centers excluded donors with blood pressure (BP) >140/90, whereas 22.7 and 7.1% excluded patients with pre-hypertension with a cut-off BP of 130/85 and 120/80, respectively. 66% of the centers used 24-hour urine creatinine to assess for proteinuria. 20% of the centers accepted living kidney donors with microalbuminuria and 84% accepted patients with a history of nephrolithiasis. 24% of the centers reported use of formal cognitive testing of potential living donors. DISCUSSION: There were significant variations in exclusion criteria based on GFR, history of kidney stones, body mass index, BP and donors with urinary abnormalities. The definitions for hematuria and proteinuria were variable. There is a need for uniformity in selection and for a living donor registry. We also recommend raising the cut-off for estimated GFR to 90 ml/min to account for 10-15% overestimation when CrCl is used.

Development of a Patient Preference Survey for Wearable Kidney Replacement Therapy Devices.

Background: Recent innovations have the potential to disrupt the current paradigm for kidney failure treatment. The US Food and Drug Administration is committed to incorporating valid scientific evidence about how patients weigh the benefits and risks of new devices into their decision making, but to date, premarket submission of patient preference information (PPI) has been limited for kidney devices. With input from stakeholders, we developed a survey intended to yield valid PPI, capturing how patients trade off the potential benefits and risks of wearable dialysis devices and in-center hemodialysis. Methods: We conducted concept elicitation interviews with individuals receiving dialysis to inform instrument content. After instrument drafting, we conducted two rounds of pretest interviews to evaluate survey face validity, comprehensibility, and perceived relevance. We pilot tested the survey with in-center hemodialysis patients to assess comprehensibility and usability further. Throughout, we used participant input to guide survey refinements. Results: Thirty-six individuals receiving in-center or home dialysis participated in concept elicitation (N=20) and pretest (N=16) interviews. Participants identified reduced fatigue, lower treatment burden, and enhanced freedom as important benefits of a wearable device, and many expressed concerns about risks related to device disconnection-specifically bleeding and infection. We drafted a survey that included descriptions of the risks of serious bleeding and serious infection and an assessment of respondent willingness to wait for a safer device. Input from pretest interviewees led to various instrument modifications, including treatment descriptions, item wording, and risk-level explanations. Pilot testing of the updated survey among 24 in-center hemodialysis patients demonstrated acceptable survey comprehensibility and usability, although 50% of patients required some assistance. Conclusions: The final survey is a 54-item web-based instrument that will yield estimates of the maximal acceptable risk for the described wearable device and willingness to wait for wearable devices with lower risk.

Poor outcomes in elderly kidney transplant recipients receiving alemtuzumab induction.

INTRODUCTION: Alemtuzumab and rabbit antithymocyte globulin (rATG) are being used with increasing frequency as induction agents in kidney transplantation. Using the US Renal Data Base System, we analyzed the safety profile of these agents in the elderly. METHODS: In a cohort of patients transplanted from January 2000 to July 2009 and followed through 2009, we assessed the effect of induction on allograft loss and death among elderly recipients. Recipients were censored at dates of allograft loss, death or the end of study. Independent associations between induction agents and allograft loss or death were examined using multivariate analysis with forward stepwise Cox regression. RESULTS: Among 130,402 patients with first transplants, 14,907 were age 65 years or older. 4,466 (30%), 3,049 (20.5%), 1,501 (10.1%), and 999 (6.7%) were induced with thymoglobulin, basiliximab, daclizumab, and alemtuzumab, respectively. After adjusting for baseline differences, induction with alemtuzumab was associated with an increased risk of graft loss and death, with an adjusted hazard ratio (AHR) of 1.26 (95% CI 1.08-1.48). Risk was also present at other age cutoffs [age >60 (AHR 1.16; 95% CI 1.03-1.31; p = 0.014), age >70 (AHR 1.43; 95% CI 1.13-1.81; p = 0.003) and age >75 (AHR 1.68; 95% CI 1.07-2.63; p = 0.024)]. CONCLUSIONS: In the elderly, alemtuzumab is associated with an escalating risk of death and graft loss in recipients of kidney transplantations.

Arteriovenous fistulas among incident hemodialysis patients in Department of Defense and Veterans Affairs facilities.

A higher proportion of patients initiate hemodialysis (HD) with an arteriovenous fistula (AVF) in countries with universal health care systems compared with the United States. Because federally sponsored national health care organizations in the United States, such as the Department of Veterans Affairs (DVA) and the Department of Defense (DoD), are similar to a universal health care model, we studied AVF use within these organizations. We used the US Renal Data System database to perform a cross-sectional analysis of patients who initiated HD between 2005 and 2006. Patients who received predialysis nephrology care had 10-fold greater odds of initiating dialysis with an AVF (adjusted odds ratio [aOR] 10.3; 95% confidence interval [CI] 9.6 to 11.1). DVA/DoD insurance also independently associated with initiating HD with an AVF (aOR 1.4; 95% CI 1.2 to 1.5). Fewer patients initiated HD at a DoD facility, but these patients were also approximately twice as likely to use an AVF (aOR 2.3; 95% CI 1.2 to 4.6). In conclusion, patients in DVA/DoD systems are significantly more likely to use an AVF at initiation of HD than patients with other insurance types, including Medicare. Further study of these federal systems may identify practices that could improve processes of care across health care systems to increase the number of patients who initiate HD with an AVF.

Cardiovascular risk assessment among potential kidney transplant candidates: approaches and controversies.

Cardiovascular disease is the most common cause of death after kidney transplantation. However, uncertainties regarding the optimal assessment of cardiovascular risk in potential transplant candidates have produced controversy and inconsistency in pretransplantation cardiac evaluation practices. In this review, we consider the evidence supporting cardiac evaluation in kidney transplant candidates, generally focused on coronary artery disease, according to the World Health Organization principles for screening. The importance of pretransplant cardiac evaluation is supported by the high prevalence of coronary artery disease and the incidence and adverse consequences of acute coronary syndromes in this population. Testing for coronary artery disease may be performed noninvasively by using modalities that include nuclear myocardial perfusion studies and dobutamine stress echocardiography. These tests have prognostic value for mortality, but imperfect sensitivity and specificity for detecting angiographically defined coronary artery disease in patients with end-stage renal disease. Associations of angiographically-defined coronary artery disease with subsequent survival also are inconsistent, likely because plaque instability is more critical for infarction risk than angiographic stenosis. The efficacy and best methods of myocardial revascularization have not been examined in large contemporary clinical trials in patients with end-stage renal disease. Biomarkers, such as cardiac troponin, have prognostic value in end-stage renal disease, but require further study to determine clinical applications in directing more expensive and invasive cardiac evaluation.

New-onset diabetes after hemodialysis initiation: impact on survival.

BACKGROUND: The incidence of new-onset diabetes after initiation of hemodialysis (NODAD) and its impact on survival is not known. METHODS: We used data from the United States Renal Data System (USRDS) from January 2000 to December 2001, with at least 3 years of follow-up for this study. Patients aged 18-80 years were included. NODAD was defined as two Medicare institutional claims for diabetes in patients with no history of diabetes prior to starting hemodialysis (HD). Incidence (per 1,000 patient-years), prevalence (%) and hazard ratios for mortality in patients with NODAD were calculated. RESULTS: There were 59,340 incident patients with no history of diabetes prior to starting HD, of which 3,853 met criteria for NODAD. The overall incidence and prevalence of NODAD were 20 per 1,000 patient-years and 7.6%, respectively. In a cohort of 444 patients without diabetes and documented glycosylated hemoglobin A1c, <6% prior to starting HD (from January 2005 and March 2006), at a mean follow-up of 4.7 +/- 2.6 months, 6.8% developed NODAD defined by two Medicare claims for diabetes after initiation of HD. NODAD was associated with a significantly increased risk of death as compared to non-diabetes patients (hazard ratio 1.20, 95% confidence interval 1.14-1.25). CONCLUSION: The USRDS showed a high incidence of NODAD, associated with significantly higher mortality compared to those who did not develop NODAD. The mechanism of NODAD needs to be explored further in experimental and clinical studies.

Toward Patient-Centered Innovation: A Conceptual Framework for Patient-Reported Outcome Measures for Transformative Kidney Replacement Devices.

Individuals with dialysis-dependent kidney failure experience considerable disease- and treatment-related decline in functional status and overall well-being. Despite these experiences, there have been few substantive technological advances in KRT in decades. As such, new federal initiatives seek to accelerate innovation. Historically, integration of patient perspectives into KRT product development has been limited. However, the US Food and Drug Administration recognizes the importance of incorporating patient perspectives into the total product life cycle (i.e., from product conception to postmarket surveillance) and encourages the consideration of patient-reported outcomes in regulatory-focused clinical trials when appropriate. Recognizing the significance of identifying patient-reported outcome measures (PROMs) that capture contemporary patient priorities, the Kidney Health Initiative, a public-private partnership between the American Society of Nephrology and US Food and Drug Administration, convened a workgroup to (1) develop a conceptual framework for a health-related quality of life PROM; (2) identify and map existing PROMs to the conceptual framework, prioritizing them on the basis of their supporting evidence for use in the regulatory environment; and (3) describe next steps for identifying PROMs for use in regulatory clinical trials of transformative KRT devices. This paper summarizes the proposed health-related quality-of-life PROM conceptual framework, maps and prioritizes PROMs, and identifies gaps and future needs to advance the development of rigorous, meaningful PROMS for use in clinical trials of transformative KRT devices.

Acute phosphate nephropathy.

PURPOSE OF REVIEW: Acute phosphate nephropathy (APN) has been identified in renal biopsy specimens of patients exposed to oral sodium phosphate (OSP) bowel purgatives. Biopsy confirmed cases presented with bland urinary sediment, low-grade proteinuria, and varying degrees of creatinine elevation. Prospective identification of APN is difficult in that definitive diagnosis requires renal biopsy, and biopsy is rarely performed for patients with this clinical presentation. RECENT FINDINGS: Observational studies evaluating acute kidney injury after OSP exposure using interval changes in creatinine as a surrogate for APN have reported conflicting results. Although these studies have produced estimates of disease occurrence, they have been unable to definitively quantify the overall risk of APN with OSP as compared with alternative bowel-cleansing agents. SUMMARY: On the basis of association of APN and OSP, the US Food and Drug Administration issued a boxed warning and manufacturers have ceased production and distribution of some OSP products. As this is a temporary solution, more studies are needed to delineate the pathophysiology of this disease and to better identify the subset of the population at risk for APN.

Incidence, predictors and outcomes of transplant renal artery stenosis after kidney transplantation: analysis of USRDS.

OBJECTIVE: We analyzed the United States Renal Data System registry to study the risks, predictors, and outcomes of transplant renal artery stenosis (TRAS) in contemporary practice. METHODS: The study sampled comprised adults with Medicare primary insurance who received kidney transplants in 2000-2005. We examined associations of recipient, donor and transplant factors with time-to-TRAS by the Kaplan-Meier method and multivariate Cox regression. Survival analysis methods were employed to estimate graft survival after TRAS, and to model TRAS as a time-dependent outcome predictor. Kaplan-Meier analysis was used to estimate time to allograft loss in patients who did or did not have an angioplasty procedure for TRAS. RESULTS: There were 823 cases of TRAS among 41,867 transplant patients, with an incidence rate of 8.3 (95% CI 7.8-8.9) cases per 1,000 patient-years. Mean time to diagnosis of TRAS was 0.83 + or - 0.81 years after transplant. Factors associated with TRAS were older recipient and donor age, extended criteria donors, induction immunosuppression, delayed graft function, and ischemic heart disease. There was no association of TRAS with deceased donors, prolonged cold ischemia time, acute rejection or cytomegalovirus status. TRAS was associated with increased risk of graft loss (including death; adjusted hazard ratio 2.84, 95% CI 1.70-4.72). Among the 823 patients with TRAS, 145 (17.6%) underwent angioplasty. Graft survival after TRAS was not significantly different in patients treated with angioplasty compared to those without angioplasty. CONCLUSIONS: TRAS is an important complication that predicts adverse patient and graft outcomes. Treatment strategies for TRAS warrant prospective investigation in clinical trials.

Outcomes in African-Americans vs. Caucasians using thymoglobulin or interleukin-2 receptor inhibitor induction: analysis of USRDS database.

AIM: We used the USRDS database to test the hypothesis that graft survival was similar using either rabbit antithymocyte globulin (rATG) vs. interleukin-2 receptor inhibitor (IL2i) in the Prograf era. We further explored the variable of race in the two groups of patients. METHODS: We conducted a retrospective cohort study of kidney transplant patients in the USRDS from 2000 through 2005 to compare graft survival (including death) using rATG vs. IL2i with particular reference to outcomes between African-Americans vs. Caucasians. Kaplan-Meier analysis was performed to assess patient and graft survival after transplantation, stratified by recipient induction with rATG versus IL2i. Cox regression analysis was performed to assess adjusted survival after transplantation, assessing whether induction rATG (vs. IL2i) was significant as an interaction term (i.e. an effect modifier) with black race for graft survival. Propensity score analysis was used to address potential confounding by indication. RESULTS: In stratified Cox Regression analysis limited to IL2i, black race was significantly associated with graft loss (adjusted hazard ratio (AHR) 1.17, 95% CI, 1.09-1.26). In analysis limited to rATG induction, black race was not significant (AHR 1.00, 95% CI, 0.92-1.10). We detected a significant interaction between rATG and black race (in comparison with non-black race) for the development of graft loss (AHR, 0.86, 95% CI, 0.76-0.97). Analysis limited to black recipients showed that while use of rATG was not significantly different from IL2i (AHR 0.95, 95% CI 0.87-1.04), the direction of this association was in the opposite direction of non-blacks. CONCLUSIONS: Patient and graft survival were similar in African-American and Caucasian recipients of kidney transplantation using either rATG or IL2i. Limitations of the study are the retrospective nature of USRDS data, center-bias in using rATG vs. IL2i and lack of data on steroid dosage. Results of the present study call for a critical review of induction practices.

Incidence, predictors and associated outcomes of rhabdomyolysis after kidney transplantation.

BACKGROUND: There are several case reports of rhabdomyolysis (RM) in renal transplant recipients, but the actual incidence of this complication is not known. Most of the reported cases have been attributed to drug-drug interactions with calcineurin inhibitors, with the majority of interactions reported between cyclosporine and 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins). Pharmacokinetic studies have demonstrated that cyclosporine increases statin drug levels, presumably via competitive inhibition of cytochrome P450 3A4. METHODS: In a retrospective cohort of 20 366 adult Medicare primary renal transplant recipients in the USRDS database transplanted from 1 January 2003 to 31 July 2005 and followed through 31 December 2005, we assessed Medicare claims for RM and dyslipidaemia (HPL), which was used as a surrogate for statin use. RESULTS: The incidence rate of RM post-transplant for the study period was 1.4 (95% CI 1.1-1.8) per 1000 person-years. By Cox regression analysis, cyclosporine (versus tacrolimus) use [AHR 2.36 (95% CI 1.23-4.35); P = 0.006] and black race [AHR 2.33 (95% CI 1.30-4.17); P = 0.005] were associated with RM. By Cox non-proportional hazards regression, RM was associated with graft loss (including death) [AHR 2.84 (95% CI 1.70-4.72); P < 0.001]. CONCLUSIONS: RM is a rare complication after renal transplantation and is significantly associated with allograft loss (including death). RM is significantly more likely to occur with cyclosporine (versus tacrolimus)-based immunosuppression and possibly in persons of black race. Increased surveillance for RM is warranted in these at-risk patients.

A Technology Roadmap for Innovative Approaches to Kidney Replacement Therapies: A Catalyst for Change.

The number of patients dialyzed for ESKD exceeds 500,000 in the United States and more than 2.6 million people worldwide, with the expectation that the worldwide number will double by 2030. The human cost of health and societal financial cost of ESKD is substantial. Dialytic therapy is associated with an unacceptably high morbidity and mortality rate and poor quality of life. Although innovation in many areas of science has been transformative, there has been little innovation in dialysis or alternatives for kidney replacement therapy (KRT) since its introduction approximately 70 years ago. Advances in kidney biology, stem cells and kidney cell differentiation protocols, biomaterials, sensors, nano/microtechnology, sorbents and engineering, and interdisciplinary approaches and collaborations can lead to disruptive innovation. The Kidney Health Initiative, a public-private partnership between the American Society of Nephrology and the US Food and Drug Administration, has convened a multidisciplinary group to create a technology roadmap for innovative approaches to KRT to address patients' needs. The Roadmap is a living document. It identifies the design criteria that must be considered to replace the myriad functions of the kidney, as well as scientific, technical, regulatory, and payor milestones required to commercialize and provide patient access to KRT alternatives. Various embodiments of potential solutions are discussed, but the Roadmap is agnostic to any particular solution set. System enablers are identified, including vascular access, biomaterial development, biologic and immunologic modulation, function, and safety monitoring. Important Roadmap supporting activities include regulatory alignment and innovative financial incentives and payment pathways. The Roadmap provides estimated timelines for replacement of specific kidney functions so that approaches can be conceptualized in ways that are actionable and attract talented innovators from multiple disciplines. The Roadmap has been used to guide the selection of KidneyX prizes for innovation in KRT.

Hyperkalemia after packed red blood cell transfusion in trauma patients.

BACKGROUND: Published analyses of clinical outcomes for patients requiring large-volume blood transfusion conflict with respect to the impact upon plasma potassium levels. We analyzed a cohort of trauma patients to ascertain the impact of component product transfusion upon plasma potassium values. METHODS: We performed an observational analysis of previously, prospectively collected clinical data on 131 noncrush trauma patients undergoing resuscitation during the initial 12 hours after admission to a combat support hospital. Comparisons were made between those who received packed red blood cell (PRBC) transfusion and those who did not. Primary outcome was hyperkalemia (plasma potassium level >5.5 mmol/L). RESULTS: Ninety-six of one hundred thirty-one patients (73.3%) received PRBCs (mean number of PRBC units 11.2, range, 0-55.0). For transfusion versus nontransfusion patients, baseline plasma potassium value (3.7 +/- 0.57 mmol/L vs. 3.6 +/- 0.36 mmol/L, p = 0.22) rose significantly after transfusion (5.3 +/- 1.2 mmol/L, vs. 4.0 +/- 0.78 mmol/L, p < 0.001). During the study period, 38.5% of transfusion patients developed hyperkalemia, versus 2.9% of those who did not (p = 0.003). In multivariate logistic regression analysis, transfusion of greater than 7 units of PRBCs was independently associated with the development of hyperkalemia (RR 4.72, 95% CI 1.01-21.97, p = 0.048). Transfusion of other cell-based products, baseline base deficits, and plasma bicarbonate levels were not. Spearman's rank correlation coefficient for the relationship of number of transfused PRBC units to the highest recorded potassium value was 0.554 (p < 0.001). The predictive accuracy of the logistic regression model for hyperkalemia was 0.824 (95% CI 0.747-0.901, p < 0.001). CONCLUSIONS: Hyperkalemia is common after PRBC transfusion, and often severe. PRBC transfusion is independently associated with the development of hyperkalemia. The findings suggest the need for interventional studies examining the impact of alternative resuscitative approaches after severe trauma.

Principles of effective consultation: an update for the 21st-century consultant.

BACKGROUND: Little information in the literature exists to guide consult interactions between different medical specialties. METHODS: A total of 323 general internists, family medicine physicians, general surgeons, orthopedic surgeons, and obstetricians/gynecologists (OB/GYNs) from 3 academic medical centers completed a survey addressing their ideal relationship with consultants. Differences between surgeons and nonsurgeons were calculated using logistic regression, adjusting for location and trainee status. Differences between different specialties of surgeons were calculated using analysis of variance with Scheffe post hoc analysis RESULTS: There was a 72% response rate. About half of respondents were surgeons and the rest were general internists and family medicine physicians. More nonsurgeons (69%) desired the consultant to focus on a narrow question than did surgeons (41%). Over half (59%) of family medicine physicians and internists preferred to retain order-writing authority on their patients compared with 37% of surgeons (P<.001). Of the surgeons preferring to retain authority, 70% believed it was appropriate for consultants to write orders after a verbal discussion. Orthopedic surgeons desired consultants to write orders and co-manage patients significantly more compared with general surgeons and OB/GYNs (P<.001). Only 29% of physicians thought literature references were useful in consultations. Most physicians (75%) desired direct verbal communication with the specialist providing the consultation. Most family physicians (78%) believed there was little need for general internal medicine input, preferring to consult medicine subspecialists directly. CONCLUSIONS: Specialty-dependent differences exist in consult preferences of physicians. These differences vary from the extremes of orthopedic surgeons desiring a comprehensive co-management approach with the consultant to general internists and family medicine physicians desiring to retain control over order writing and have a more focused consultant approach.

Association of oral sodium phosphate purgative use with acute kidney injury.

Oral sodium phosphate (OSP) is a commonly used purgative before colonoscopy. There have been numerous reports of acute phosphate nephropathy attributed to the use of OSP. This study evaluated the association between the use of OSP and acute kidney injury (AKI) in an observational, retrospective, cohort study. Of 9799 patients who underwent colonoscopy and had serum creatinine values recorded within 365 days before and after the procedure, AKI, defined as > or =50% increase in baseline serum creatinine, was identified in 114 (1.16%). After adjustment for significant covariates in a multiple logistic regression model, the use of OSP was associated with increased risk for AKI (odds ratio 2.35; 95% confidence interval 1.51 to 3.66; P < 0.001) with an adjusted number need to harm of 81. Age was also independently associated with AKI in this cohort; therefore, until larger, prospective studies define the population at risk for acute phosphate nephropathy, the use of polyethylene glycol-based purgatives should be considered for older patients and possibly for those with comorbid medical conditions.

FDA Regulatory Perspectives for Studies on Hemodialysis Vascular Access.

In an effort to foster innovation and new product development, the American Society of Nephrology and the US Food and Drug Administration partnered to form the Kidney Health Initiative in 2012. Part of the Kidney Health Initiative's mission is to foster development of therapies by creating a collaborative environment where the US Food and Drug Administration and the greater nephrology community can interact to optimize product evaluation. This particular Kidney Health Initiative project focused on products related to hemodialysis vascular access, with the goal of clarifying appropriate trial end points that could subsequently inform clinical, regulatory, and coverage decisions. Both the lack of common definitions and the lack of consensus on trial end points have been viewed as barriers to innovation in this area. Toward this end, the Kidney Health Initiative convened teams of expert stakeholders to address these issues for each major vascular access category (arteriovenous grafts, arteriovenous fistulas, and central venous catheters), and each team provided recommendations. This commentary provides an overview of the US Food and Drug Administration centers that regulate hemodialysis vascular access and certain laws and regulations that affect these products as well as our perspectives on some of the issues raised and end points proposed by the Kidney Health Initiative teams. The standardized definitions and clinical trial end points proposed by the teams represent an important step forward to improve innovation in this area.