Risk Factors for Peritoneal Dialysis-Related Infections

Objective

To identify factors associated with peritoneal dialysis-related infections at one center.

Design

The study was a retrospective study of a 3 year time period with relatively stable treatment patterns.

Setting

A single center experienced academic peritoneal dialysis program.

Patients

Patients (N = 163) receiving peritoneal dialysis (PD) from January 1989 to December 1991 who had received treatment at home for at least one month.

Interventions

None.

Main Outcome Measures

Catheter-related infection and peritonitis were the main outcome measures. Variables affecting infection rates that were assessed included age, time on PD, prior end-stage renal disease (ESRD) therapy, diabetic status, catheter type, exchange device, nasal carriage of S. aureus, and prophylactic rifampin therapy. Data were analyzed with univariate as well as with a fixed-effects and a mixed-effects gamma Poisson multiple regression model.

Results

Variables associated with an increased risk of new peritonitis included age under 20 years (p < 0.009; rate ratio 4.54) and nasal carriage of S. aureus (p < 0.04; rate ratio 1.75). Decreased new peritonitis risk was associated with the ULTRA Set exchange system (p < 0.008; risk ratio 0.38) and intermittent prophylactic rifampin therapy (p < 0.001; rate ratio 0.99 for each 1% time on therapy). Catheter-related infections were increased in patients who had double-cuff catheters (p < 0.003) and nasal carriage of S. aureus (p < 0.04; rate ratio 1.82). Decreased catheter-related infections were noted in older patients (p < 0.02; rate ratio 0.983/year) and increasing months of study follow - up (p < 0.03; rate ratio 0.97/month).

Conclusion

In our program nasal carriage of S. aureus increased the risk of peritonitis and catheter-related infection. Prophylactic rifampin significantly decreased peritonitis, as did use of the UL TRA Set. Single-cuff opaque catheters had the lowest catheter infection rate. Analysis of the relationships between clinical and demo graphic variables and peritoneal dialysis-related infection rate can identify significant contributing or protective variables and allow peritoneal dialysis programs to develop preventive strategies to minimize the risk of infection.

Comparison of Intraperitoneal and Subcutaneous Epoetin Alfa in Peritoneal Dialysis Patients

Objective

To compare the efficacy of intraperitoneal (IP) and subcutaneous (SC) administration of epoetin alfa in patients receiving peritoneal dialysis (PD).

Design

A 32-week prospective, randomized, cross-over experimental design.

Setting

Two university-based outpatient PD centers.

Patients

Twenty adult PD patients receiving stable doses of SC epoetin alfa enrolled in the study. Thirteen patients completed 32 weeks of follow-up.

Intervention

Patients were randomly assigned to receive either SC or IP epoetin alfa at the start of the study. Dose adjustments were made to maintain baseline hematocrit ± 3 percentage points. Following 16 weeks of treatment, patients crossed over to the other route of administration for an additional 16 weeks. Intraperitoneal epoetin alfa was administered into an empty peritoneal cavity for approximately 8 hours before resuming dialysis. End-of-study IP epoetin alfa doses required to maintain target hematocrit were given twice weekly ( n = 1), once weekly ( n = 11), or once every other week ( n = 1). All patients received iron supplements to maintain or exceed prestudy iron parameters.

Main Outcome Measure

Prior to the study, the primary outcome measure was defined as the difference in epoetin alfa dose between IP and SC administration.

Results

Thirteen patients completed the study. The area under the dosing-requirement curve for IP epoetin alfa was larger than for SC administration ( p = 0.0029), and the slope of the 16-week dose-requirement curve was greater for IP administration ( p = 0.017), suggesting greater dose stability for SC administration. Paired analysis indicated greater IP intrapatient dose requirements ( p < 0.0001). The mean difference in SC versus IP doses was 5000 ± 1510 units per week. Some patients required escalating IP doses to maintain target hematocrit values. Iron administration and iron stores were similar in both groups.

Conclusion

Intraperitoneal epoetin alfa may be a suitable alternative for some patients for whom SC dosing is undesirable. Large IP versus SC dosing differences noted in a few patients are unexplained, but may result from interpatient variability in IP epoetin alfa absorption. Intraperitoneal dosing into an empty peritoneum can be done safely and effectively.

Characteristics of Long Term Peritoneal Dialysis Survivors: 18 Years Experience in One Center

Objectives

Long-term experience of patients on peritoneal dialysis (PD) in general, and in diabetic patients specifically, is limited. Few patients have been followed on PD for over 8 years. Our aim was to evaluate and characterize long-term survivors (L TS) on PD for more than 100 months. A retrospective analysis of 20 patients who survived on PD for more than 100 months was performed. Data on long-term survivors was compared to data of 103 patients who died or switched to hemodialysis (HD) in less than 100 months.

Design

The study included all patients starting PD prior to 1 January 1986. Demographic, biochemical, dialysis prescription, and morbidity data were obtained on these patients. Characteristics of long-term survivors on PD (more than 100 months), was compared with those who died or switched to HD in less than 100 months, using Student t-test.

Setting

An experienced single center, university-based dialysis program.

Patients

165 patients started PD at the University of Wisconsin prior to 1 January 1986. Forty three had type I diabetes mellitus and 24 had type II diabetes mellitus as the cause of their renal failure.

Results

Twenty patients survived on PD more than 100 months (L TS). Long-term survival of type I diabetic patients was seen in 7 of 43 patients at risk. Seventeen type I diabetics received renal transplants and ten died. 103 patients either died or switched to HD in less than 100 months. Long-term survivors were significantly younger, weighed less, had fewer episodes of peritonitis, fewer hospital days, and were prescribed more dialysis per kg body weight, than those who died or switched to HD prior to 100 months.

Conclusions

Long-term survival on CAPD for longer than 100 months is possible with survival periods up to 18 years in both males and females and in nondiabetics as well as patients with type I diabetes mellitus. No patient with type II diabetes mellitus survived longer than 100 months on CAPD. In comparison to short-term survivors, long-term survivors were characterized by being younger, weighing less, having fewer episodes of peritonitis, fewer hospital days, and were prescribed more dialysis/kg body weight.

Opportunities to Improve Shared Decision Making in Dialysis Decisions for Older Adults with Life-Limiting Kidney Disease: A Pilot Study

Background: Lack of awareness about the life-limiting nature of renal failure is a significant barrier to palliative care for older adults with end-stage renal disease. Objective: To train nephrologists to use the best case/worst case (BC/WC) communication tool to improve shared decision making about dialysis initiation for older patients with limited life expectancy. Design: This is a pre-/postinterventional pilot study. Setting/Subjects: There were 16 nephrologists and 30 patients of age 70 years and older with estimated glomerular filtration rate (eGFR) <20 mL/min per 1.73 m² in outpatient nephrology clinics, in Madison, WI. Measurements: Performance of tool elements, content of communication about dialysis, shared decision making, acceptability of the intervention, decisions to pursue dialysis, and palliative care referrals were measured. Results: Fifteen of 16 nephrologists achieved competence performing the BC/WC tool with standardized patients, executing at least 14 of 19 items. Nine nephrologists met with 30 patients who consented to audio record their clinic visit. Before training, clinic visits focused on laboratory results and preparation for dialysis. After training, nephrologists noted that declining kidney function was "bad news," presented dialysis and "no dialysis" as treatment options, and elicited patient preferences. Observer-measured shared decision-making (OPTION 5) scores improved from a median of 20/100 (interquartile range [IQR] 15-35) before training to 58/100 (IQR 55-65). Patients whose nephrologist used the BC/WC tool were less likely to make a decision to initiate dialysis and were more likely to be referred to palliative care. Conclusions: Nephrologists can learn to use the BC/WC tool with older patients to improve shared decision making about dialysis, which may increase access to palliative care.

Initial vascular access type in patients with a failed renal transplant

BACKGROUND AND OBJECTIVES

Permanent hemodialysis vascular access is crucial for RRT in ESRD patients and patients with failed renal transplants, because central venous catheters are associated with greater risk of infection and mortality than arteriovenous fistulae or arteriovenous grafts. The objective of this study was to determine the types of vascular access used by patients initiating hemodialysis after a failed renal transplant.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from the US Renal Data System database on 16,728 patients with a failed renal transplant and 509,643 patients with native kidney failure who initiated dialysis between January 1, 2006, and September 30, 2011 were examined.

RESULTS

At initiation of dialysis, of patients with a failed transplant, 27.7% (n=4636) used an arteriovenous fistula, 6.9% (n=1146) used an arteriovenous graft, and 65.4% (n=10,946) used a central venous catheter. Conversely, 80.8% (n=411,997) of patients with native kidney failure initiated dialysis with a central venous catheter (P<0.001). Among patients with a failed transplant, predictors of central venous catheter use included women (adjusted odds ratio, 1.75; 95% confidence interval, 1.63 to 1.87), lack of referral to a nephrologist (odds ratio, 2.00; 95% confidence interval, 1.72 to 2.33), diabetes (odds ratio, 1.14; 95% confidence interval, 1.06 to 1.22), peripheral vascular disease (odds ratio, 1.31; 95% confidence interval, 1.16 to 1.48), and being institutionalized (odds ratio, 1.53; 95% confidence interval, 1.23 to 1.89). Factors associated with lower odds of central venous catheter use included older age (odds ratio, 0.85 per 10 years; 95% confidence interval, 0.83 to 0.87), public insurance (odds ratio, 0.74; 95% confidence interval, 0.68 to 0.80), and current employment (odds ratio, 0.87; 95% confidence interval, 0.80 to 0.95).

CONCLUSIONS

Central venous catheters are used in nearly two thirds of failed renal transplant patients. These patients are usually followed closely by transplant physicians before developing ESRD after a failed transplant, but the relatively low prevalence of arteriovenous fistulae/arteriovenous grafts in this group at initiation of dialysis needs to be investigated more thoroughly.

The effect of buttonhole cannulation vs. rope-ladder technique on hemodialysis access patency

The rope-ladder (RL) technique is the most common technique used for cannulation of arteriovenous fistulae (AVF). Buttonhole cannulation (BHC), or constant-site technique, is recommended by the National Kidney Foundation's Kidney Disease Outcome Quality Initiative (NKF/KDOQI) vascular access guidelines. We compared outcomes of primary patency, episodes of bacteremia, access blood flow (Qa), and quality of life (QoL) scores between RL and BHC patients. Using a prospectively collected, vascular access database, a total of 45 prevalent dialysis patients using BHC were compared with 38 patients using the RL technique over a median of 12 months (inter-quartile range: 4-27 months). The two groups did not differ significantly in demographics except that diabetes was more common in those using BHC as compared to rope-ladder (69% vs. 34%; p = 0.002). Risk factors associated with lack of primary patency were age (hazards ratio [HR] = 1.02 per decade; 95% CI: 1.00-1.03; p = 0.04) and female gender (HR = 1.92; 95% CI: 1.08-3.40; p = 0.03). Use of the buttonhole technique was not associated with improved primary patency (HR = 1.22, 95% CI: 0.65-2.28; p = 0.53). Episodes of bacteremia and mean scores from KDQOL-36 did not differ significantly between the groups. This study demonstrates for the first time that BHC use is not associated with improved access patency.

Concentrated Heparin Lock Is Associated with Major Bleeding Complications after Tunneled Hemodialysis Catheter Placement

Vascular access complications, including thrombosis, are associated with significant patient morbidity and mortality. Currently, up to 60% of new patients and 30% of prevalent patients are using a catheter for dialysis. To prevent interdialytic catheter thrombosis, these devices are routinely locked with concentrated heparin solutions. Several recent studies have elucidated the potential for abnormal coagulation markers (aPTT) that may arise from this practice. This abnormal elevation in aPTT may be explained by significant early and late leakage from the catheter that occurs after performing a catheter lock. To date no study has evaluated the impact of this practice, or the elevation in aPTT that may result from it, on bleeding complication rates. We conducted a retrospective analysis comparing bleeding rates in subjects who received concentrated heparin catheter lock (5000 u/cc) [group 1, n = 52] to those who received citrate or dilute heparin catheter lock (1000 u/cc) [group 2, n = 91] immediately after tunneled hemodialysis catheter insertion. Baseline characteristics did not differ between the groups except for the preprocedure INR, which was higher in the postpolicy group compared with the prepolicy group (1.29 vs. 1.21, p = 0.04). Results from logistic regression analyses revealed that the likelihood of a composite bleeding event in group 1 was 11.9 times that of a composite bleeding event in group 2, p = 0.04. Concentrated heparin (5000 u/ml) is associated with increased major bleeding complications posttunneled catheter placement compared with low-dose heparin (1000 u/ml) or citrate catheter lock solution, p = 0.02. Given the findings of this study, a randomized controlled trial comparing the safety and efficacy of common anticoagulation lock solutions is warranted.

Comparison of intraperitoneal and subcutaneous epoetin alfa in peritoneal dialysis patients

OBJECTIVE

To compare the efficacy of intraperitoneal (i.p.) and subcutaneous (s.c.) administration of epoetin alfa in patients receiving peritoneal dialysis (PD).

DESIGN

A 32-week prospective, randomized, cross-over experimental design.

SETTING

Two university-based outpatient PD centers.

PATIENTS

Twenty adult PD patients receiving stable doses of s.c. epoetin alfa enrolled in the study. Thirteen patients completed 32 weeks of follow-up.

INTERVENTION

Patients were randomly assigned to receive either s.c. or i.p. epoetin alfa at the start of the study. Dose adjustments were made to maintain baseline hematocrit +/- 3 percentage points. Following 16 weeks of treatment, patients crossed over to the other route of administration for an additional 16 weeks. Intraperitoneal epoetin alfa was administered into an empty peritoneal cavity for approximately 8 hours before resuming dialysis. End-of-study i.p. epoetin alfa doses required to maintain target hematocrit were given twice weekly (n = 1), once weekly (n = 11), or once every other week (n = 1). All patients received iron supplements to maintain or exceed prestudy iron parameters.

MAIN OUTCOME MEASURE

Prior to the study, the primary outcome measure was defined as the difference in epoetin alfa dose between i.p. and s.c. administration.

RESULTS

Thirteen patients completed the study. The area under the dosing-requirement curve for i.p. epoetin alfa was larger than for s.c. administration (p = 0.0029), and the slope of the 16-week dose-requirement curve was greater for i.p. administration (p = 0.017), suggesting greater dose stability for s.c. administration. Paired analysis indicated greater i.p. intrapatient dose requirements (p < 0.0001). The mean difference in s.c. versus i.p. doses was 5000 +/- 1510 units per week. Some patients required escalating i.p. doses to maintain target hematocrit values. Iron administration and iron stores were similar in both groups.

CONCLUSION

Intraperitoneal epoetin alfa may be a suitable alternative for some patients for whom s.c. dosing is undesirable. Large i.p. versus s.c. dosing differences noted in a few patients are unexplained, but may result from interpatient variability in i.p. epoetin alfa absorption. Intraperitoneal dosing into an empty peritoneum can be done safely and effectively.

Association between human recombinant EPO and peripheral vascular disease in diabetic patients receiving peritoneal dialysis

Peripheral vascular disease is a serious and frequent problem in diabetic patients. Since the beginning of the widespread use of erythropoietin (EPO), we have noted an increase in peripheral vascular disease in diabetic patients receiving peritoneal dialysis and erythropoietin. This prompted us to study the effects of erythropoietin on peripheral vascular disease in patients receiving peritoneal dialysis. We retrospectively reviewed medical records of all diabetic patients in our program who received peritoneal dialysis from 1990 to 1996. Demographic and laboratory data as well as EPO use data were collected. Hospital days and occurrence of vascular events (defined as peripheral vascular surgery, amputation, or recommendation of vascular surgery or amputation by a vascular surgeon) were determined for diabetic patients receiving peritoneal dialysis. Comparisons were made between those who received EPO and those who did not received EPO, as well as comparing vascular events in 28 patients who received peritoneal dialysis before and after beginning EPO. Patients who received erythropoietin were found to have a significantly shorter time to a first vascular event, a greater number of vascular events, and more hospital days associated with vascular disease than diabetic patients who did not receive erythropoietin. With multivariate analysis, significant risk factors for the development of peripheral vascular disease in these patients were erythropoietin use, erythropoietin dose, and smoking. Twenty-eight patients who initially performed peritoneal dialysis without receiving EPO, and later received EPO, had a significant increase in vascular events, including amputations only while receiving EPO. We found the use of erythropoietin to be associated with peripheral vascular events in diabetic patients who receive peritoneal dialysis. Further investigation is warranted.

Characteristics of long-term peritoneal dialysis survivors: 18 years experience in one center

OBJECTIVES

Long-term experience of patients on peritoneal dialysis (PD) in general, and in diabetic patients specifically, is limited. Few patients have been followed on PD for over 8 years. Our aim was to evaluate and characterize long-term survivors (LTS) on PD for more than 100 months. A retrospective analysis of 20 patients who survived on PD for more than 100 months was performed. Data on long-term survivors was compared to data of 103 patients who died or switched to hemodialysis (HD) in less than 100 months.

DESIGN

The study included all patients starting PD prior to 1 January 1986. Demographic, biochemical, dialysis prescription, and morbidity data were obtained on these patients. Characteristics of long-term survivors on PD (more than 100 months), was compared with those who died or switched to HD in less than 100 months, using Student t-test.

SETTING

An experienced single center, university-based dialysis program.

PATIENTS

165 patients started PD at the University of Wisconsin prior to 1 January 1986. Forty three had type I diabetes mellitus and 24 had type II diabetes mellitus as the cause of their renal failure.

RESULTS

Twenty patients survived on PD more than 100 months (LTS). Long-term survival of type I diabetic patients was seen in 7 of 43 patients at risk. Seventeen type I diabetics received renal transplants and ten died. 103 patients either died or switched to HD in less than 100 months. Long-term survivors were significantly younger, weighed less, had fewer episodes of peritonitis, fewer hospital days, and were prescribed more dialysis per kg body weight, than those who died or switched to HD prior to 100 months.

CONCLUSIONS

Long-term survival on CAPD for longer than 100 months is possible with survival periods up to 18 years in both males and females and in nondiabetics as well as patients with type I diabetes mellitus. No patient with type II diabetes mellitus survived longer than 100 months on CAPD. In comparison to short-term survivors, long-term survivors were characterized by being younger, weighing less, having fewer episodes of peritonitis, fewer hospital days, and were prescribed more dialysis/kg body weight.

Long-term outcome of diabetic patients receiving peritoneal dialysis

OBJECTIVE

Data from the United States Renal Data Systems (USRDS) suggest that older diabetic patients with end-stage renal disease will have improved survival if they receive hemodialysis versus peritoneal dialysis. Younger diabetic patients have equal survival on either treatment modality. To address more specifically the risk factors for long-term survival of diabetic patients receiving peritoneal dialysis, we analyzed the long-term outcome of 118 diabetics receiving peritoneal dialysis over a decade and compared them to 165 nondiabetic patients.

DESIGN

Retrospective analysis utilizing the Cox proportional hazards model to identify risk factors for survival of both diabetic and nondiabetic patients.

SETTING

An experienced, single-center, university-based dialysis program.

PATIENTS

All patients receiving home peritoneal dialysis for at least one month from 1 January 1981 to 31 December 1990. Diabetics were classified as type I or type II, in addition to age stratification. Most type I diabetic patients used insulin via the intraperitoneal route.

MAIN OUTCOME MEASURES

Patient survival and technique survival.

RESULTS

The most significant risk factor for diabetic patient survival was diabetes type (relative risk type I to type II 0.14, p < 0.0001). On treatment serum albumin, predialysis blood urea nitrogen and predialysis serum cholesterol were also significant risk factors (p < 0.01). For nondiabetic patients, age, on treatment serum albumin, and current smoking were significant survival risk factors. Survival of patients 55 years or less was not significantly different between diabetic and nondiabetic patients. Survival of patients greater than 55 years was better in nondiabetic patients.

CONCLUSION

These findings of a long-term follow-up period suggest a good survival for younger type I diabetic patients receiving peritoneal dialysis. Reasons other than age for the discrepancy in survival of young versus old diabetics receiving peritoneal dialysis should be sought.

Renal replacement therapy in diabetic nephropathy

The case of a patient with diabetes mellitus and renal failure is presented and discussed. This case represents the very successful course of a diabetic patient who received peritoneal dialysis for 14 years. Not all patients with end-stage renal disease (ESRD) from diabetic nephropathy are this fortunate. The success and complications of dialytic modalities are discussed by a nephrologist and nurse dialysis coordinator. Renal transplantation, the preferred treatment for most diabetic ESRD patients, is discussed by a nurse transplant coordinator. Simultaneous pancreas kidney transplantation, with its potential benefits in the future is discussed by an experienced transplant surgeon. In addition, the psychosocial issues of renal failure, dialysis, and transplantation in the diabetic patient are addressed by clinical social workers. Lastly, the very important issue of foot care and treatment, and prevention of vascular-related morbidity is discussed by a practicing podiatrist. With such a multidisciplinary approach, medical and psychosocial outcomes can be optimized for diabetic patients with renal failure.