Organ donors with positive viral serology or malignancy: risk of disease transmission by transplantation.
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Biomedical subjects
Publications and source records attributed to David Roth.
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Several studies have documented the effectiveness of bupropion for smoking cessation, yet little is known about the mechanisms by which it facilitates abstinence. In this placebo-controlled randomized trial. We examined whether bupropion's effects on cessation were mediated by changes in withdrawal and/or negative or positive affect (PA). Two hundred and fifty-one smokers received 10-week treatment with bupropion or placebo, plus behavioral counseling. Changes in affect and withdrawal symptoms from pre-quit to 1 week post quit were examined as mediating variables in structural equation models. Cotinine-verified 7-day point prevalence cessation rates at the end of treatment (8-weeks post quit date) were 48% for bupropion and 29% for placebo (P=0.001). There were significant treatment effects on withdrawal and negative affect (NA); however, only change in NA predicted cessation. In a path model, change in NA was a significant mediator of bupropion's effects on cessation. However, the proportion of variance accounted for by this mediator was small, suggesting that other unmeasured factors play an important role. Laboratory-based paradigms may be useful to identify other mediators of bupropion's effects, thereby pointing to mechanisms of effect that can be bolstered in future treatment studies.
BACKGROUND: Recent reports have demonstrated the efficacy of interleukin-2-receptor blockers in lowering the incidence of early acute rejection in cyclosporine-treated kidney recipients when compared to patients not induced with an antibody product. The addition of daclizumab to a tacrolimus-mycophenolate mofetil-based immunosuppressive protocol was tested to evaluate whether there might be an additional reduction of the risk of rejection after renal transplantation. METHODS: Since March 1998, we studied the effect of daclizumab in a nonrandomized, prospective study of 233 sequential recipients of first renal transplant. They were retrospective compared with a control group of 225 renal transplant recipients receiving a 10-day course of OKT3 induction, and tacrolimus, mycophenolate mofetil, and methylprednisolone maintenance. The study group received the same immunosuppressive regimen with the addition of daclizumab at 1 mg/kg for five doses over 10 weeks in the place of OKT3 therapy. There was at least 1HLA DR antigen compatibility match present between all donors and recipients. Patients were followed for 1 year after renal transplantation for the incidence of biopsy-proven acute rejection, patient and graft survival, and adverse events. RESULTS: At 12 months, patient and graft survival for the daclizumab was 98 and 96 vs. 96 and 94% for the OKT3 group, respectively, and were not statistically different. Acute rejection rates (<6 months) were lower in the daclizumab group as compared with the OKT3 group, i.e., 5 (2.1%) vs. 16 (7.1%) (P=0.011) respectively. The incidence of infection requiring hospitalization appeared to be lower with daclizumab (7.3 vs. 16%, P<0.0036) with a similar trend with cyclomegalovirus infection, i.e., 1.6 vs. 4%, respectively (P=0.14). CONCLUSIONS: The combination of daclizumab, tacrolimus, mycophenolate mofetil, and steroids is safe and effective for kidney transplant recipients in lowering the incidence of early acute rejection and without any increase in morbidity when compared to our previous protocol, which may have an eventual impact in long-term graft survival.
Jeune's syndrome is a rare inherited cause of kidney failure associated with skeletal dysplasia in children. We report the case of a 20-year-old girl who had Jeune's syndrome type 2 and underwent a second kidney transplant after failure of the first allograft. The patient had 16 years of good allograft function with the first transplant and successfully received a second cadaveric graft.
BACKGROUND: Metabolic alkalosis (MA) is common after orthotopic liver transplantation (OLT). METHODS: The study was conducted to identify factors associated with MA after 285 OLTs. MA, defined as total carbon dioxide content of 30 mEq/L or greater, developed in 115 patients (40%) within the first 3 postoperative days. RESULTS: By univariate analysis, patients with MA had a greater preoperative carbon dioxide content (24.4 +/- 3 versus 22.9 +/- 2.9 mEq/L; P < 0.0001) and hematocrit (35% +/- 5% versus 33% +/- 6%; P < 0.02), but lower creatinine (0.9 +/- 0.5 versus 1.2 +/- 1.2 mg/dL; P < 0.001) and blood urea nitrogen levels (15 +/- 12 versus 19 +/- 17 mg/dL; P < 0.001) compared with controls. Patients with MA were administered more citrate intraoperatively compared with controls (6.2 +/- 5.2 versus 4.5 +/- 3.6 mEq/kg of body weight; P < 0.02). Patients with MA had a lower postoperative potassium level (3.7 +/- 0.4 versus 4 +/- 0.5 mEq/L; P < 0.0001) and cumulative fluid balance (-0.66 +/- 1.87 versus +0.003 +/- 3.9 L; P < 0.007) compared with controls. By multivariate analysis, preoperative carbon dioxide content (odds ratio, 1.19; 95% confidence interval [CI], 1.08 to 1.31 per mEq/L), creatinine level (odds ratio, 0.61; 95% CI, 0.39 to 0.96 per mg/dL), intraoperative administered citrate (odds ratio, 3.35; 95% CI, 1.71 to 6.53 per 10 mEq/kg body weight), and postoperative potassium level (odds ratio, 0.32; 95% CI, 0.18 to 0.57 per mEq/L) were independently associated with MA. MA was not associated with increased hospital mortality (7.8% versus 8.2%, MA versus controls). However, patients with MA spent more time on mechanical ventilation than controls (5 +/- 0.8 versus 3 +/- 0.6 days; P < or = 0.03). CONCLUSION: Preoperative total carbon dioxide content, renal function, intraoperative administered citrate, and postoperative potassium level are independently associated with MA after primary OLT.
The preoperative impairment of renal function is associated with the need for postoperative renal replacement therapy (RRT) in patients undergoing liver transplantation. The principal goal of this investigation was to identify other factors apparent before or during transplant that were independently associated with the need for RRT in the early posttransplant period. A total of 260 consecutive adult patients who received a primary liver transplant were studied. Twenty-eight patients required early RRT (RRT initiated within 1 wk of transplant); 23 for control of volume overload. Preoperative blood urea nitrogen (odds ratio [95% CI], 1.52 [1.15 to 2.01] per 10 mg/dl), serum creatinine (1.91 [1.06 to 3.44] per 1 mg/dl), and urine output (0.12 [0.03 to 0.44] L/d) were independently predictive of the need for early RRT and in combination formed a parsimonious model that discriminated well (area under the receiver operating characteristic curve, 0.877) and had excellent fit (P = 0.699 to reject model fit). No other potential predictors meaningfully improved predictions of which patients would require early RRT. Patients requiring early RRT consumed more healthcare resources than patients who did not require early RRT, spending more time in intensive care (15 +/- 13 d versus 7 +/- 11 d; P < 0.001) and in the hospital (34 +/- 27 d versus 19 +/- 20 d; P < 0.001). The need for early RRT was strongly associated with death before hospital discharge (29% mortality versus 4% mortality among all others; P < 0.001). The data demonstrate that dependency on RRT in the first week after orthotopic liver transplantation stems almost entirely from preoperative renal dysfunction.
The Clinical Practice Guidelines Committee of the American Society of Transplantation developed a survey to review the policies of kidney transplant programs in the United States with respect to the management of the steadily expanding waiting list for cadaveric kidneys. The survey was sent to 287 centers, and 192 (67%) responded. The survey indicated that regular follow-up monitoring, most frequently on an annual basis, is required by the majority (71%) of programs. Patients considered to be at high risk and candidates for combined kidney-pancreas transplantation may be monitored more frequently. Annual screening for coronary artery disease is typically required for asymptomatic patients considered to be at high risk for covert disease. Noninvasive techniques are typically used, and a designated cardiologist is usually available to the transplant program. The dialysis nephrologist or the potential transplant recipient is expected to inform the transplant program of intercurrent events that may affect transplant candidacy. Standard health maintenance screening is required, together with the routine updating of serologic and other blood tests that may be relevant to the posttransplant course. Smaller transplant programs (<100 patients on the waiting list) are more likely to maintain closer contact with the wait-listed patients and to attempt to influence their treatment during dialysis and are less likely to cancel transplants because of unanticipated pretransplant medical problems. The work load necessitated by the follow-up monitoring of wait-listed patients was assessed and, in the absence of specific evidence-based information, a series of recommendations were developed to reflect current standards of practice and to suggest future research initiatives.
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OBJECTIVE: Although the benefits of coronary stenting have been demonstrated in several large clinical trials, controversy remains as to whether stenting results in long-term cost savings compared to percutaneous transluminal coronary angioplasty (PTCA). The objective of this study was to evaluate the resource use and cost (Medicare payment) of PTCA versus bare stent in actual practice over a 2-year period. METHODS: The data for this study came from the 1996 through 1998 Standard Analytic Files that contain 5% of Medicare claims. The rates of repeat revascularization procedures and hospitalizations were reported at 1 and 2 years. Costs associated with inpatient admission, outpatient procedures, physician services, skilled nursing facility admissions, and home health-care services were included to perform a comprehensive assessment. Regression analysis was performed to test for cost differences controlling for case-mix variation between the patient groups. RESULTS: The selection process yielded 3782 PTCA patients and 2690 stent patients for analysis. The rate of revascularization was 26.7% for the PTCA group and 22.2% for the stent group at 2 years. The mean total cost for the initial procedure was 13,724 dollars for PTCA and 15,021 dollars for stenting. At 2 years, the total cumulative cost was 32,654 dollars for the PTCA group and 32,102 dollars for the stent group, a difference that was not statistically significant. CONCLUSION: Although the difference in the rate of repeat revascularization procedures between PTCA and stenting is not as large as those reported in clinical trials, bare stents are cost-neutral when compared to PTCA for the Medicare population.
Peritoneal dialysis (PD) is an underutilized form of renal replacement therapy. Recent data have emphasized that only 12% of end-stage renal disease (ESRD) patients are initiated on this form of therapy in the United States. Patients requiring PD have most often been referred to general surgeons for catheter placement. This has incurred additional delays in starting treatment and loss of decision-making control by the referring nephrologist. To address this issue, we developed and incorporated our own PD access placement program into the preexisting chronic kidney disease (CKD) education program. To date, 46 patients have undergone 71 procedures. These included 51 (72%) PD catheter insertions, 14 (20%) removals, and 6 (8%) repositioning procedures for poor drainage. PD catheter insertion was performed peritoneoscopically under local anesthesia and a Fogarty catheter was used to reposition a migrated catheter. All of the procedures were performed by nephrologists in a dedicated interventional nephrology (IN) laboratory. All six repositioning procedures failed to restore optimal drainage. Five of these patients had the catheter removed and a new catheter placed during the same procedure. Of these five patients, one had recurrence of poor drainage and opted for hemodialysis (HD). The sixth patient declined reinsertion and chose HD. Of the remaining seven removal procedures, three were due to fungal peritonitis, one due to bowel perforation, one due to severe depression, one due to transplant, and one catheter was removed at the request of the primary physician in a terminally ill patient. Eight of the 51 catheter insertions were during the initial admission of a catastrophic dialysis start. Two of these patients started acute PD and avoided catheter placement for HD. Thirty-seven of 46 patients have a functional PD catheter with a follow-up of 8.6 +/- 0.8 (mean +/- SE) months. During an 18-month period our PD population has increased from 43 to 80 patients. We conclude that a dedicated PD access placement program coupled with a CKD education program can have a dramatic impact on patient choice and PD growth.
The fragmented care of nephrology patients that results from referral to a radiologist for renal ultrasound (US) and biopsy, a surgeon for dialysis access placement, and an interventional radiologist for dialysis catheter placement and vascular access procedures often leads to delays in the treatment of these patients. Many specialists perform and interpret sonograms particular to their specialty rather than relying on technicians for performance and radiologists for interpretation, and nephrologists recently have begun to embrace this technology as an aid in the diagnosis and treatment of their patients. By combining an understanding of the pathophysiology of renal disease with the ability to perform clinical correlation and apply the laboratory data, the nephrologist is ideally suited to perform and interpret renal US and US guidance for percutaneous renal biopsies. Additionally, patients requiring peritoneal dialysis (PD) access have traditionally been referred to a general surgeon for catheter placement, which incurs additional delay in therapy and loss of decision-making control by the referring nephrologist. Recent data has emphasized that the peritoneal dialysis access procedure can be performed safely and effectively by a nephrologist trained in PD access procedures. Nephrologists also successfully perform tunneled hemodialysis catheter placement and vascular access procedures on an outpatient basis. The medical needs of patients with renal disease can be safely and efficiently delivered by a nephrologist trained in interventional nephrology (IN). This growing area of expertise will minimize delays, reduce cost, and allow physicians with training in the management of end-stage renal disease (ESRD) patients to be involved in the procedural aspects of their patients' care. An aggressive approach to the development of IN training programs at academic centers is warranted.
Radiocontrast administration remains the third leading cause of hospital-acquired acute renal failure. Clinically, radiocontrast-induced nephropathy (RIN) is defined as a sudden decline in renal function after radiocontrast administration. Typically, the serum creatinine level begins to increase at 24 to 72 hours after the administration of contrast, peaks at 3 to 5 days, and requires another 3 to 5 days to return to baseline. RIN increases the incidence of life-threatening complications such as sepsis, bleeding, and respiratory failure and increases the cost of medical care by extending the hospital stay. The increased mortality associated with acute renal failure encountered in this scenario calls for a heightened awareness of the diagnosis and prevention of RIN. Whereas individuals with healthy renal function are not generally considered to be at particular risk for RIN, patients with preexisting renal insufficiency and diabetes mellitus are much more likely to experience acute renal failure after contrast administration. In the past, a variety of therapeutic interventions have been used to prevent or attenuate RIN, including saline hydration, diuretics, mannitol, calcium channel antagonists, theophylline, endothelin receptor antagonists, hemodialysis, and dopamine. More recently, studies demonstrate a positive impact of fenoldopam (dopamine-1 receptor, dopamine-1 agonist) and the antioxidant N-acetylcysteine in ameliorating RIN. This article discusses the pathophysiology, risk factors, and prevention of RIN.
A retrospective cohort study based on claims and medical chart data was conducted to compare healthcare use and costs in congestive heart failure patients with and without carvedilol. Adult patients with a minimum of two claims with a valid congestive heart failure diagnosis from 1997 to 1999 were included. Patients receiving continuous carvedilol treatment for at least 4 months were considered study case patients. Case patients were matched based on age, gender, race, and concomitant medication. Healthcare use and costs were compared between the case and control groups. A total of 128 case and 147 control patients were identified. There were no significant differences in demographic characteristics, concomitant medication, or New York Heart Association classification between these two groups. Analysis of variance and chi-square analyses were conducted for continuous and categorical variables, respectively. Statistical adjustments were made using a multivariate model. Carvedilol had a significant economic reduction in the overall expenditures by approximately $14,530. Facility expenditures were approximately $9,000 lower for the carvedilol group than for the control group. Carvedilol-treated patients had less frequent hospital admissions and shorter lengths of stay compared with patients not receiving carvedilol. Congestive heart failure patients receiving carvedilol have significantly less healthcare use and costs than patients not receiving carvedilol.
Radiocontrast administration is a common cause of hospital-acquired acute renal failure. It is associated with significant in-hospital and long-term morbidity and mortality and increases the costs of medical care by at least extending the hospital stay. A variety of therapeutic interventions, including saline hydration, diuretics, mannitol, calcium channel antagonists, theophylline, endothelin receptor antagonists, and dopamine, have been employed to prevent radiocontrast-induced acute renal failure. Recent advances have examined the impact of fenoldopam (dopamine-1 receptor agonist), N-acetylcysteine (antioxidant), iso-osmolar contrast agents, hemodialysis, and hemofiltration on ameliorating radiocontrast-induced acute renal failure. Although hydration with half-normal saline had remained the gold standard for the prevention of radiocontrast-induced nephropathy, recent data have revealed the superiority of hydration with normal saline over half-normal saline. This review focuses on the most recent studies of interventions to ameliorate radiocontrast-induced acute renal failure and provides a critical analysis of some of the recent studies conducted to prevent radiocontrast-induced nephropathy.
Bowel perforation is a well-recognized complication of peritoneal dialysis catheter insertion and is associated with increased morbidity and cost of medical care. In this article we describe our 2-year experience (August 2001-October 2003) with a modified peritoneoscopic technique of peritoneal dialysis catheter insertion to minimize the incidence of bowel perforation. Seventy patients underwent 82 consecutive peritoneal dialysis catheter insertions using the innovative technique. The modified technique is very similar to the traditional peritoneoscopic procedure except for the following differences. To gain access to the peritoneal cavity, a Veress insufflation needle (Ethicon Endo-Surgery Inc., Cincinnati, OH) is utilized instead of the trocar. In contrast to the sharp tip of the trocar, the Veress needle has a blunt, self-retracting end. In addition, the Veress needle is only 14 gauge as opposed to the 2.2 mm diameter of the trocar. Upon introduction of the Veress needle into the abdominal cavity, two "pops" are discerned similar to the trocar. After introduction, 400-500 cc of air are infused and the needle is removed. The infusion of air creates a space between the peritoneal surface of the anterior abdominal wall and the bowel loops. At this point, the cannula with trocar is inserted into the space created. The rest of the steps of the procedure are the same as the traditional peritoneoscopic technique. Utilizing the innovative technique, all 82 catheter insertions were performed successfully without a single bowel perforation. No other complications except for catheter migration (n = 2) were noted. The extra cost of the needle (35 USD) should be viewed in the context of the costs associated with management of a bowel perforation. Large-scale studies are needed to confirm the superiority of this innovative technique over the traditional peritoneoscopic insertion found in our case series. In the interim, however, the increased morbidity and cost associated with bowel perforation calls for logical measures to be taken to avoid this dreaded complication.
Traditionally hemodialysis vascular access-related procedures have been almost exclusively performed by surgeons and interventional radiologists. In recent years, nephrologists have taken the initiative of performing these procedures themselves. Because of their unique clinical perspective on dialysis access and better understanding of the intricacies of renal replacement therapy, nephrologists are ideally suited for this activity. This approach has minimized delays, decreased hospitalizations, and decreased the use of temporary catheters, thereby improving medical care, decreasing costs, and increasing patient convenience. Vascular access-related procedures commonly performed by nephrologists include percutaneous balloon angioplasty, thrombectomy, and tunneled hemodialysis catheter-related procedures. In addition, using vein obliteration and percutaneous balloon angioplasty techniques, nephrologists have recently documented successful salvage of arteriovenous fistulas that had failed to mature, whereas traditionally these fistulas have frequently been abandoned. While the performance of these procedures by nephrologists offers many advantages, appropriate training in order to develop the necessary procedural skills is critical. Recent data have emphasized that a nephrologist can be successfully trained to become a competent interventionalist. In addition to documenting excellent outcome data, multiple reports have demonstrated the safety and success of interventional nephrology. This review focuses on hemodialysis access-related procedures performed by nephrologists and calls for a proactive approach in optimizing this aspect of patient care.
National Kidney Foundation Dialysis Outcomes Quality Initiative (NKF-DOQI) guideline 29 suggests that a patient should be evaluated for a secondary arteriovenous fistula (AVF) following each episode of dialysis access failure. Regretfully, it does not appear that this approach is used, even though recent data have emphasized that veins suitable for the creation of a secondary AVF can be identified in dialysis patients who are receiving dialysis via a synthetic arteriovenous graft (AVG) or other type of potentially dysfunctional vascular access. In this study nine patients (five with an AVG and four with an AVF) with vascular access dysfunction undergoing percutaneous interventions were evaluated for secondary AVF creation. All were found to have suitable vascular anatomy and had the AVF created. The secondary fistula was successful in all nine patients with a mean follow-up of 4.8 +/- 1.4 months in post-AVG cases and 5.6 +/- 1.7 months in the post-AVF patients. In addition, it was possible to continue uninterrupted dialysis without the use of a tunneled dialysis catheter in three of the patients with AVGs. This experience demonstrates the validity and success of this approach to the management of dialysis access dysfunction. In the ongoing effort to optimize vascular health status, we suggest that during percutaneous interventions, patients should routinely have identification of vessels suitable for creation of a secondary AVF.
In contrast to hemodialysis (HD), peritoneal dialysis (PD) remains an underutilized form of renal replacement therapy in the United States. Although a variety of factors have been deemed responsible, timely insertion of a PD catheter may also be a contributory factor. We conducted a multicenter analysis to examine whether the establishment of a program for PD catheter insertion by nephrologists has a positive impact on the growth in the number of patients using PD. Data for catheter insertion performed by nephrologists were collected from three centers. Any change in the prevalent PD population at each respective center was compared to the number of PD patients during the period having the traditional surgical approach. Nephrologists at the three centers used the peritoneoscopic technique and performed catheter insertion under local anesthesia. In center 1, the PD population remained stable at between 38 and 45 patients (approximately 16% of the total end-stage renal disease [ESRD] population) from 1993 to 2001. Nephrologists initiated a program for PD catheter insertion in 2001. The number of PD patients has increased to 101 (32% of the ESRD population). In center 2, the PD population remained stable at between 70 and 78 patients (approximately 17%) between 1988 and 1990. Catheter insertion by interventional nephrologists began in 1991. The number of PD patients has increased to 125 (22%). In center 3, the PD population remained at 20-30 patients (approximately 18%) between 1988 and 1991. Catheter placement by nephrologists was initiated in 1991. The number of PD patients increased to 97 (27%). Catheter insertion by interventional nephrologists was suspended in 2001. The number of PD patients has gradually declined to 25 (6%). This study suggests that catheter insertion by the nephrologist can have a positive impact on the utilization of PD.