The Association of Intra-Abdominal Adhesions with Peritoneal Dialysis Catheter-Related Complications

BACKGROUND

This study investigated the association of intra-abdominal adhesions with the risk of peritoneal dialysis (PD) catheter complications.

METHODS

Individuals undergoing laparoscopic PD catheter insertion were prospectively enrolled from eight centers in Canada and the United States. Patients were grouped based on the presence of adhesions observed during catheter insertion. The primary outcome was the composite of PD never starting, termination of PD, or the need for an invasive procedure caused by flow restriction or abdominal pain.

RESULTS

Seven hundred and fifty-eight individuals were enrolled, of whom 201 (27%) had adhesions during laparoscopic PD catheter insertion. The risk of the primary outcome occurred in 35 (17%) in the adhesion group compared with 58 (10%) in the no adhesion group (adjusted HR, 1.64; 95% confidence interval [CI], 1.05 to 2.55) within 6 months of insertion. Lower abdominal or pelvic adhesions had an adjusted HR of 1.80 (95% CI, 1.09 to 2.98) compared with the no adhesion group. Invasive procedures were required in 26 (13%) and 47 (8%) of the adhesion and no adhesion groups, respectively (unadjusted HR, 1.60: 95% CI, 1.04 to 2.47) within 6 months of insertion. The adjusted odds ratio for adhesions for women was 1.65 (95% CI, 1.12 to 2.41), for body mass index per 5 kg/m 2 was 1.16 (95% CI, 1.003 to 1.34), and for prior abdominal surgery was 8.34 (95% CI, 5.5 to 12.34). Common abnormalities found during invasive procedures included PD catheter tip migration, occlusion of the lumen with fibrin, omental wrapping, adherence to the bowel, and the development of new adhesions.

CONCLUSIONS

People with intra-abdominal adhesions undergoing PD catheter insertion were at higher risk for abdominal pain or flow restriction preventing PD from starting, PD termination, or requiring an invasive procedure. However, most patients, with or without adhesions, did not experience complications, and most complications did not lead to the termination of PD therapy.

Impact of Prior Abdominal Procedures on Peritoneal Dialysis Catheter Outcomes: Findings From the North American Peritoneal Dialysis Catheter Registry

RATIONALE & OBJECTIVE

A history of prior abdominal procedures may influence the likelihood of referral for peritoneal dialysis (PD) catheter insertion. To guide clinical decision making in this population, this study examined the association between prior abdominal procedures and outcomes in patients undergoing PD catheter insertion.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Adults undergoing their first PD catheter insertion between November 1, 2011 and November 1, 2020, at 11 institutions in Canada and the US participating in the International Society for Peritoneal Dialysis (ISPD) North American Catheter Registry.

EXPOSURE

Prior abdominal procedure(s), defined as any procedure that enters the peritoneal cavity.

OUTCOMES

Primary outcome: time to the first of abandonment of the PD catheter, or interruption/termination of PD.

SECONDARY OUTCOMES

rates of emergency room visits, hospitalizations, and procedures.

ANALYTICAL APPROACH

Cumulative incidence curves were used to describe the risk over time and an adjusted Cox proportional hazards model was used to estimate the association between the exposure and primary outcome. Models for count data were used to estimate the associations between the exposure and secondary outcomes.

RESULTS

A total of 855 patients met the inclusion criteria. Thirty-one percent had a history of a prior abdominal procedure and 20% experienced at least one PD catheter-related complication that led to the primary outcome. Prior abdominal procedures were not associated with an increased risk of the primary outcome [Adjusted HR 1.12 (95% CI 0.68-1.84)]. Upper abdominal procedures were associated with a higher adjusted hazard of the primary outcome, but there was no dose-response relationship concerning the number of procedures. There was no association between prior abdominal procedures and other secondary outcomes.

LIMITATIONS

Observational study and cohort limited to sample of patients felt to be potential candidates for PD catheter insertion.

CONCLUSION

A history of prior abdominal procedure(s) does not appear to influence catheter outcomes following PD catheter insertion. Such a history should not be a contraindication to peritoneal dialysis.

Patient Training and Patient Safety in Home Hemodialysis

The success of a home hemodialysis program depends largely on a patient safety framework and the risk tolerance of a home dialysis program. Dialysis treatments require operators to perform dozens of steps repeatedly and reliably in a complex procedure. For home hemodialysis, those operators are patients themselves or their care partners, so attention to safety and risk mitigation is front of mind. While newer, smaller, and more user-friendly dialysis machines designed explicitly for home use are slowly entering the marketplace, teaching patients to perform their own treatments in an unsupervised setting hundreds of times remains a foundational programmatic obligation regardless of machine. Just how safe is home hemodialysis? How does patient training affect this safety? There is a surprising lack of literature surrounding these questions. No consensus exists among home hemodialysis programs regarding optimized training schedules or methods, with each program adopting its own approach on the basis of local experience. Furthermore, there are little available data on the safety of home hemodialysis as compared with conventional in-center hemodialysis. This review will outline considerations for training patients on home hemodialysis, discuss the safety of home hemodialysis with an emphasis on the risk of serious and life-threatening adverse effects, and address the methods by which adverse events are monitored and prevented.

Predictors of Care Gaps in Home Dialysis: The Home Dialysis Virtual Ward Study

BACKGROUND

Home dialysis patients may be at an increased risk of adverse events after transitional states. The home dialysis virtual ward (HDVW) trial was conducted in Canadian dialysis centers and aimed to evaluate potential care gaps and patient satisfaction during the HDVW.

METHODS

The HDVW was a multicenter single-arm trial including peritoneal dialysis and home hemodialysis patients after 4 different events (hospital discharge, medical procedure, antibiotics, completion of training). Telephone-led interviews using a standardized assessment tool were performed over a 2-week period to assess a patient's care and adjust treatment as required. Upon completion, patients were surveyed to evaluate their perceived impact on domains of care using a rating scale; 1 not satisfied to 10 completely satisfied.

RESULTS

The HDVW trial included 193 patients with a median number of potential care gaps/interventions of 1 (0-2) per patient. Patients admitted to the HDVW after hospital discharge were at a higher risk of potential gaps in care (OR 2.16, 95% CI 1.29-3.62), while longer dialysis vintage was -associated with a lower number of gaps/interventions (OR 0.97 per year, 95% CI 0.95-0.98). A total of 105/193 (54%) patients completed satisfaction surveys. Patients were highly satisfied with the HDVW (median rating scale score 8, IQR 2) and felt it had a positive impact (rating scale score ≥7) on their overall health, understanding of treatment and access to a nephrologist.

CONCLUSION

The HDVW was effective at identifying several potential care gaps, and patients were satisfied across several domains of care. This intervention may be valuable in supporting home dialysis patients during care transitions.

Impact of Ramadan fasting on kidney function and related outcomes in patients with chronic kidney disease: a systematic review protocol

INTRODUCTION

Fasting during the month of Ramadan is a significant Islamic religious practice that involves abstinence from food, drink and medication from dawn to dusk. As just under a quarter of the world's population identifies as Muslim, the effect of fasting on chronic conditions, such as chronic kidney disease (CKD) is a topic of broad relevance. To date, the information in this area has been mixed, with many limitations of previous studies. This study aims to synthesise the evidence of the effect of Ramadan fasting on changes on kidney function, risk factors, episodes of acute kidney injury and impact on the quality of life in patients with CKD or kidney transplant.

METHODS AND ANALYSIS

A systematic review of the literature will be conducted, using electronic databases such as MEDLINE, Embase, Global Health, CINAHL and Scopus. Original research and grey literature on the effect of Ramadan fasting in adult patients with CKD or renal transplantation will be included. Two reviewers will independently screen articles for inclusion in the review and independently assess the methodology of included studies using a customised checklist. Mean difference or risk ratio will be reported for continuous or dichotomous outcomes and results will be pooled using a random-effects model where heterogeneity is reasonable. If possible, subgroups (CKD status, setting, season and risk of bias) will be analysed for effect modification with fasting and the outcomes of interest. Risk of bias will be assessed using the Downs and Black checklist.

ETHICS AND DISSEMINATION

The results will be disseminated using a multifaceted approach to engage all stakeholders (patients, practitioners and community leaders). Research ethics board approval is not required as this is a systematic review of previously published research.

PROSPERO REGISTRATION NUMBER

CRD42018088973.

Acute Kidney Injury in Pregnant Patient With Pancreas-Kidney Transplant Caused by Abdominal Compartment Syndrome: A Case Presentation, Review of Literature, and Proposal of Diagnostic Approach

Rationale:

With increasing number of complex medical patients with renal transplant who get pregnant, clinicians need to be aware of abdominal compartment syndrome which may masquerade as acute renal allograft injury in pregnancy.

Presenting concerns of the patient:

A 34-year-old nulliparous Caucasian female with end-stage renal disease (ESRD) due to type 1 diabetes mellitus who received a simultaneous pancreas-kidney transplant (SPK) in 2006 and then after rejection of renal allograft another, kidney-only allograft from a donation after circulatory death became pregnant in May 2013 with dichorionic, diamniotic twins without reproductive technology, and during pregnancy, she developed two episodes of acute injury to the renal allograft.

Diagnoses:

End-stage renal disease secondary to type I diabetes, acute renal allograft injury, tacrolimus toxicity, abdominal pain.

Interventions (including prevention and lifestyle):

She received intravenous hydration, medications contributing to renal failure were held, and pain and nauseas were controlled appropriately. Abdominal compartment syndrome was managed by maintaining intravascular pressure and optimizing regional and systemic vascular perfusion by appropriate fluid balance, evacuating intraluminal contents by decompressing gastrointestinal system, and improving abdominal wall compliance by using appropriate analgesics, sedation, and patient positioning.

Outcomes:

With advancing pregnancy, the patient developed progressive abdominal pain, nausea, leg edema, and rising creatinine that were not responsive to ongoing therapies and required delivery via Cesarean section at 31 weeks of gestational age.

Lessons learned:

In the era of increasing number of pregnant renal transplant patients with multiple medical issues, we need organized approach to diagnosis of acute renal allograft injury in pregnancy and we need to consider abdominal compartment syndrome as one of the causes.

Prospective monitoring of after-hours nursing and technologist support calls to a regional Canadian home hemodialysis program

INTRODUCTION

Increasing renal care providers offer home hemodialysis (HD) as a modality choice. There is considerable variation in the provision of after-hours on-call support for self-dialyzing patients and no literature describing the utility of this service. In this prospective, observational study we sought to monitor and classify the number and nature of interactions between home patients and our on-call nurses and technologists, and enumerate the number of adverse events averted by the availability of on-call staff.

METHODS

Our home HD unit provided 24-hour on-call patient support and during a 4-month period in 2012, we prospectively monitored all patient calls to this service. The nature of the calls was logged as nursing-related vs. technical. Call outcomes were classified according to whether patients were able to initiate/resume their treatments or whether additional interventions were required.

FINDINGS

During this period, our program cared for 58 home HD patients. Nurses fielded 172 calls and dealt with 239 issues. One hundred nine (46%) were clinical issues including 5 (2%) of a serious nature involving potential harm; 67 (28%) related to machine setup or alarms, 36 (15%) required a technologist to resolve, and 27 (11%) were deemed non-urgent. One hundred six issues were directed to technologists in 99 calls. Issues pertained to machine malfunction (45 calls-43%), machine set-up and alarms (25 calls-24%), or the water system (24 calls-23%). Only 12 calls (11.3%) were not of a technical nature. Nursing and technologist support allowed patients to initiate or continue their treatment 75% and 71% of the time, respectively.

DISCUSSION

Home HD on-call services provide patients support to successfully continue their dialysis treatments by troubleshooting clinical and technical aspects of dialysis and by averting potential adverse events.

Quality Assurance Audit of Technique Failure and 90-Day Mortality after Program Discharge in a Canadian Home Hemodialysis Program

BACKGROUND AND OBJECTIVES

Little is known about patients exiting home hemodialysis. We sought to characterize the reasons, clinical characteristics, and pre-exit health care team interactions of patients on home hemodialysis who died or underwent modality conversion (negative disposition) compared with prevalent patients and those who were transplanted (positive disposition).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted an audit of all consecutive patients incident to home hemodialysis from January of 2010 to December of 2014 as part of ongoing quality assurance. Records were reviewed for the 6 months before exit, and vital statistics were assessed up to 90 days postexit.

RESULTS

Ninety-four patients completed training; 25 (27%) received a transplant, 11 (12%) died, and 23 (25%) were transferred to in-center hemodialysis. Compared with the positive disposition group, patients in the negative disposition group had a longer mean dialysis vintage (3.15 [SD=4.98] versus 1.06 [SD=1.16] years; P=0.003) and were performing conventional versus a more intensive hemodialysis prescription (23 of 34 versus 23 of 60; P<0.01). In the 6 months before exit, the negative disposition group had significantly more in-center respite dialysis sessions, had more and longer hospitalizations, and required more on-call care team support in terms of phone calls and drop-in visits (each P<0.05). The most common reason for modality conversion was medical instability in 15 of 23 (65%) followed by caregiver or care partner burnout in three of 23 (13%) each. The 90-day mortality among patients undergoing modality conversion was 26%.

CONCLUSIONS

Over a 6-year period, approximately one third of patients exited the program due to death or modality conversion. Patients who die or transfer to another modality have significantly higher health care resource utilization (e.g., hospitalization, respite treatments, nursing time, etc.).

Clinical safety and performance of VIVIA: a novel home hemodialysis system

Background

The VIVIA Hemodialysis System (Baxter Healthcare Corporation, Deerfield, IL, USA) was designed for patient use at home to reduce the burden of treatment and improve patient safety. It has unique features including extended use of the dialyzer and blood set through in situ hot-water disinfection between treatments; generation of on-line infusible-quality dialysate for automated priming, rinseback and hemodynamic support during hypotension and a fully integrated access disconnect sensor.

Methods

The safety and performance of VIVIA were assessed in two clinical studies. A first-in-man study was a prospective, single-arm study that involved 22 prevalent hemodialysis (HD) patients who were treated for ∼4 h, four times a week, for 10 weeks. A second clinical study was a prospective, single-arm study (6-8 h of dialysis treatment at night three times a week) that involved 17 prevalent patients treated for 6 weeks.

Results

There were 1114 treatments from the two studies (first-in-man study, 816; extended duration study, 298). Adverse events (AEs) were similar in the two studies to those expected for prevalent HD patients. No deaths and no device-related serious AEs occurred. Adequacy of dialysis ( Kt / V ) urea in both clinical trials was well above the clinical guidelines. VIVIA performed ultrafiltration accurately as prescribed in the two studies. The majority of patients achieved 10 or more uses of the dialyzer. Endotoxin levels and bacterial dialysate sampling met infusible-quality dialysate standards.

Conclusion

These results confirm the safety and expected performance of VIVIA.

In-Center Nocturnal Hemodialysis Versus Conventional Hemodialysis: A Systematic Review of the Evidence

BACKGROUND

Owing to its longer treatment duration-up to 8 hours per dialysis treatment-in-center thrice-weekly nocturnal hemodialysis (HD) is receiving greater attention. To better understand the evidence for in-center nocturnal HD, we sought to systematically review the literature to determine the effects of in-center nocturnal HD versus conventional HD on clinically relevant outcomes.

STUDY DESIGN

We searched MEDLINE, Embase, Evidence-Based Medicine Reviews (EBMR), Web of Science, and Scopus from the earliest date in the database to November 2016.

SETTING & POPULATION

Adults receiving in-center nocturnal HD compared with those receiving conventional HD.

SELECTION CRITERIA FOR STUDIES

All quasi-experimental and observational studies were considered; randomized trials were sought but not found.

PREDICTOR

Nocturnal vs conventional in-center HD.

OUTCOMES

Indexes of blood pressure and left ventricular hypertrophy, markers of anemia, measures of bone mineral metabolism, nutrition, quality of life, sleep quality, episodes of intradialytic hypotension, hospitalization, and mortality.

RESULTS

Of 2,086 identified citations, 21 met the inclusion criteria, comprising a total of 1,165 in-center nocturnal HD patients and 15,865 conventional HD patients. Although there was substantial heterogeneity in reporting of outcomes, we pooled data for measures of blood pressure, anemia, and mineral metabolism. Though heterogeneity was generally high, in-center nocturnal HD was associated with improved systolic blood pressure (-3.18 [95% CI, -5.58 to -0.78) mm Hg, increased hemoglobin levels (0.53 [95% CI, 0.11-0.94] g/dL), and lower serum phosphate levels (-0.97 [95% CI, -1.48 to -0.46] mg/dL).

LIMITATIONS

No randomized trials have been conducted to address the clinical effects of in-center nocturnal HD. The quality of the observational literature contributing to the results of this review was generally poor to moderate. Confounded outcomes are a significant concern. Publication bias and outcome reporting bias remain possibilities.

CONCLUSIONS

Relative to conventional HD, in-center nocturnal HD was associated with improvements in several clinically relevant outcomes. Other benefits may not have been detected due to small sample sizes of included studies; no prespecified outcome was worse with in-center nocturnal HD.

Estimating patient-borne water and electricity costs in home hemodialysis: a simulation

BACKGROUND

Home hemodialysis is associated with lower costs to the health care system compared with conventional facility-based hemodialysis because of lower staffing and overhead costs, and by transferring the treatment cost of utilities (water and power) to the patient. The purpose of this study was to determine the utility costs of home hemodialysis and create a formula such that patients and renal programs can estimate the annual patient-borne costs involved with this type of treatment.

METHODS

Seven common combinations of treatment duration and dialysate flows were replicated 5 times using various combinations of home hemodialysis and reverse osmosis machines. Real-time utility (electricity and water) consumption was monitored during these simulations. A generic formula was developed to allow patients and programs to calculate a more precise estimate of utility costs based on individual combinations of dialysis intensity, frequency and utility costs unique to any patient.

RESULTS

Using typical 2014 utility costs for Edmonton, the most expensive prescription was for nocturnal home hemodialysis (8 h at 300 mL/min, 6 d/wk), which resulted in a utility cost of $1269 per year; the least expensive prescription was for conventional home hemodialysis (4 h at 500 mL/min, 3 d/wk), which cost $420 per year. Water consumption makes up most of this expense, with electricity accounting for only 12% of the cost.

INTERPRETATION

We show that a substantial cost burden is transferred to the patient on home hemodialysis, which would otherwise be borne by the renal program.

Peritoneal Dialysis-Related Peritonitis Due to Abiotrophia defectiva: A Case Report

Background:

Abiotrophia defectiva is a fastidious aerobic gram-positive bacterium which is part of the normal flora of the human oral cavity. It is an unusual cause of peritoneal dialysis–related peritonitis.

Case Presentation:

We present a case of a man in his fifties with end-stage renal failure secondary to polycystic kidney disease who presented with a cloudy peritoneal fluid effluent and a cell count of 35 620 × 10⁶ cells/L with 90% polymorphonuclear cells. The fluid was cultured per unit protocol, and the organism was identified as Abiotrophia defectiva. Post–peritonitis dialysis technique review revealed frequent lapses in the use of facemask and hand washing during cycler connection and disconnection. The patient responded well to vancomycin; however, he subsequently developed ultrafiltration failure and symptoms of fluid overload and uremia and was transferred to home hemodialysis.

Conclusions:

Abiotrophia defectiva is an unusual cause of peritoneal dialysis–related peritonitis. The organism is a normal commensal of the oral cavity and may cause peritonitis in patients with nonadherence to dialysis technique. In our case, the infection was followed by peritoneal membrane failure and transfer to hemodialysis. It remains to be seen if peritonitis with Abiotrophia defectiva heralds a worse outcome.

Why take the chance? A qualitative grounded theory study of nocturnal haemodialysis recipients who decline kidney transplantation

OBJECTIVE

The objective of this study was to examine the factors that influence decision-making to forgo transplantation in favour of remaining on nocturnal haemodialysis (NHD).

DESIGN

A grounded theory approach using in-depth telephone interviewing was used.

SETTING

Participants were identified from 2 tertiary care renal programmes in Canada.

PARTICIPANTS

The study participants were otherwise eligible patients with end-stage renal disease who have opted to remain off of the transplant list. A total of 7 eligible participants were interviewed. 5 were male. The mean age was 46 years.

ANALYSIS

A constant comparative method of analysis was used to identify a core category and factors influencing the decision-making process.

RESULTS

In this grounded theory study of people receiving NHD who refused kidney transplantation, the core category of 'why take a chance when things are going well?' was identified, along with 4 factors that influenced the decision including 'negative past experience', 'feeling well on NHD', 'gaining autonomy' and 'responsibility'.

CONCLUSIONS

This study provides insight into patients' thought processes surrounding an important treatment decision. Such insights might help the renal team to better understand, and thereby respect, patient choice in a patient-centred care paradigm. Findings may also be useful in the development of education programmes addressing the specific concerns of this population of patients.

Patient safety in home hemodialysis: quality assurance and serious adverse events in the home setting

Interest in home hemodialysis (HD) is high because of the reported benefits and its excellent safety record. However, the potential for serious adverse events (AEs) exists when patients perform HD in their homes without supervision. We review the epidemiology of dialysis-related emergencies during home HD, and present a conceptual and practical framework for the prevention and management of serious AEs for those patients performing home HD. In addition, we describe a formal monitored and iterative quality assurance program, and make suggestions for the future development of safety strategies to mitigate the risk of AEs in home HD.

Left ventricular dysfunction in the haemodialysis population

Cardiovascular disease in the haemodialysis population continues to contribute to mortality and morbidity. Disorders of left ventricular geometry and function are highly prevalent and lead to increased mortality in this highly vulnerable population. Left ventricular dysfunction (LVDys), often as a result of hypertension, ischaemic cardiac disease or dilated cardiomyopathy, has not been uniformly defined in the literature making diagnosis and therapy problematic. Although routinely available, screening by echocardiography is critically volume dependent and prone to underestimation in left ventricular ejection fraction. Few randomized control trials are available to guide management with the majority of evidence requiring extrapolation from the non-dialysis population. Beyond medication, interventional cardiac procedures such as implantable cardiac defibrillator implantation and cardiac resynchronization therapy show promise. Conversion to alternative dialysis modalities such as peritoneal dialysis, short-daily or nocturnal dialysis have been attempted and are actively being explored.

Delivering home hemodialysis: is there still a role for real-time treatment monitoring?

Remote real-time treatment monitoring for home hemodialysis (HHD) was driven by concerns over patient safety in the early era of HHD. However, decades of clinical experience supported by objective data suggest that HHD is very safe and that remote monitoring is unlikely to avert serious adverse events. As a result, such remote monitoring is not routinely offered in the current era and is generally considered an unnecessary expense. However, a one-size-fits-all approach to abandon remote monitoring may overlook potential opportunities: to improve the clinical care of patients dialyzing at home; and to give patients the confidence to perform HHD in an unsupervised setting.

Cost analysis of in-centre nocturnal compared with conventional hemodialysis

Background

Provision of in-centre nocturnal hemodialysis (ICNHD; 6–8 hours thrice weekly) is associated with health benefits, but the economic implications of providing this treatment are unclear.

Objective

We conducted a health care costing study comparing ICNHD to in-centre thrice-weekly conventional hemodialysis (CvHD).

Design

Micro-costing of both ICNHD and CvHD as practiced at our centre.

Setting

Hemodialysis unit at a tertiary-care hospital in Edmonton.

Participants

An informal survey of 2 other Canadian ICNHD programs was conducted to inform practices that may deviate from ours to guide sensitivity analysis.

Measurements

Resources consumed for each strategy were determined, and the cost of each unit (CAN $2012) was used to calculate incremental costs of ICNHD and CvHD.

Methods

We focused on resources that differ between strategies (staffing, dialysis materials, and utilities). The reference case considered 1:3 staff to patient ratio; alternate scenarios explored nursing pay grade and ratio, full care vs. self-care dialysis (including training costs), and medication costs.

Results

In the reference case, ICNHD was $61 more costly per dialysis treatment compared with CvHD ($9,538 per patient per year). Incremental annual costs for staffing, dialysis materials, and utilities were $8,201, $1,193, and $144, respectively. If ICNHD reduces medication use (anti-hypertensives, bone mineral metabolism medications), the incremental cost of ICNHD decreases to $8,620 per patient per year. In a scenario of self-care ICNHD utilizing a staff-to-patient ratio of 1:10, ICNHD is more costly in year 1 ($15,196), but results in cost savings of $2,625 in subsequent years compared with CvHD.

Limitations

The findings of this cost analysis may not be generalizable to other health care systems, including other parts of Canada.

Conclusions

Compared to CvHD, provision of ICNHD is more expensive, largely driven by increased staffing costs as patients dialyze longer. Alternate staffing models, including self-care ICNHD with minimal staff, may lead to net cost savings. The incremental cost of treatment should be considered in the context of impact on patient health outcomes, staffing model, and pragmatic factors, such as current capacity for daytime CvHD and the capital costs of new dialysis stations.

Electronic supplementary material

The online version of this article (doi:10.1186/2054-3581-1-14) contains supplementary material, which is available to authorized users.

Programmatic variation in home hemodialysis in Canada: results from a nationwide survey of practice patterns

Background

Over 40% of patients with end stage renal disease in the United States were treated with home hemodialysis (HHD) in the early 1970’s. However, this number declined rapidly over the ensuing decades so that the overwhelming majority of patients were treated in-centre 3 times per week on a 3-4 hour schedule. Poor outcomes for patients treated in this fashion led to a renewed interest in home hemodialysis, with more intensive dialysis schedules including short daily (SDHD) and nocturnal (NHD). The relative infancy of these treatment schedules means that there is a paucity of data on ‘how to do it’.

Objective

We undertook a systematic survey of home hemodialysis programs in Canada to describe current practice patterns.

Design

Development and deployment of a qualitative survey instrument.

Setting

Community and academic HHD programs in Canada.

Participants

Physicians, nurses and technologists.

Measurements

Programmatic approaches to patient selection, delivery of dialysis, human resources available, and follow up.

Methods

We developed the survey instrument in three phases. A focus group of Canadian nephrologists with expertise in NHD or SDHD discussed the scope the study and wrote questions on 11 domains. Three nephrologists familiar with all aspects of HHD delivery reviewed this for content validity, followed by further feedback from the whole group. Multidisciplinary teams at three sites pretested the survey and further suggestions were incorporated. In July 2010 we distributed the survey electronically to all renal programs known to offer HHD according to the Canadian Organ Replacement Registry.

We compiled the survey results using qualitative and quantitative methods, as appropriate.

Results

Of the academic and community programs that were invited to participate, 80% and 63%, respectively, completed the survey. We observed wide variation in programmatic approaches to patient recruitment, human resources, equipment, water, vascular access, patient training, dialysis prescription, home requirements, patient follow up, medications, and the approach to non-adherent patients.

Limitations

Cross-sectional survey, unable to link variation to outcomes. Competition for patients between HHD and home peritoneal dialysis means that case mix for HHD may also vary between centres.

Conclusions

There is wide variation between programs in all domains of HHD delivery in Canada. We plan further study of the extent to which differences in approach are related to outcomes.

Electronic supplementary material

The online version of this article (doi:10.1186/2054-3581-1-11) contains supplementary material, which is available to authorized users.

Rationale for a home dialysis virtual ward: design and implementation

BACKGROUND

Home-based renal replacement therapy (RRT) [peritoneal dialysis (PD) and home hemodialysis (HHD)] offers independent quality of life and clinical advantages compared to conventional in-center hemodialysis. However, follow-up may be less complete for home dialysis patients following a change in care settings such as post hospitalization. We aim to implement a Home Dialysis Virtual Ward (HDVW) strategy, which is targeted to minimize gaps of care.

METHODS/DESIGN

The HDVW Pilot Study will enroll consecutive PD and HHD patients who fulfilled any one of our inclusion criteria: 1. following discharge from hospital, 2. after interventional procedure(s), 3. prescription of anti-microbial agents, or 4. following completion of home dialysis training. Clinician-led telephone interviews are performed weekly for 2 weeks until VW discharge. Case-mix (modified Charlson Comorbidity Index), symptoms (the modified Edmonton Symptom Assessment Scale) and patient satisfaction are assessed serially. The number of VW interventions relating to eight pre-specified domains will be measured. Adverse events such as re-hospitalization and health-services utilization will be ascertained through telephone follow-up after discharge from the VW at 2, 4, 12 weeks. The VW re-hospitalization rate will be compared with a contemporary cohort (matched for age, gender, renal replacement therapy and co-morbidities). Our protocol has been approved by research ethics board (UHN: 12-5397-AE). Written informed consent for participation in the study will be obtained from participants.

DISCUSSION

This report serves as a blueprint for the design and implementation of a novel health service delivery model for home dialysis patients. The major goal of the HDVW initiative is to provide appropriate and effective supports to medically complex patients in a targeted window of vulnerability.

TRIAL REGISTRATION

(NCT01912001).

Survival comparison between intensive hemodialysis and transplantation in the context of the existing literature surrounding nocturnal and short-daily hemodialysis

Our contemporary paradigms of nocturnal and short-daily hemodialysis (NHD and SDHD) have their origins in the earliest era of dialysis care for end-stage renal disease. However, these therapies have received considerably more attention in recent years owing to an increasing body of literature, suggesting a myriad of benefits attributable to these intensive dialysis regimens compared with conventional thrice-weekly hemodialysis. Analyses suggest a survival benefit for NHD and SDHD versus traditional hemodialysis prescriptions, and it is in this context that survival comparisons between intensive dialysis and transplantation must be considered. This literature and its limitations are reviewed here.

Dialysate calcium concentration and mineral metabolism in long and long-frequent hemodialysis: a systematic review and meta-analysis for a Canadian Society of Nephrology clinical practice guideline

BACKGROUND

Patients treated with conventional hemodialysis (HD) develop disorders of mineral metabolism that are associated with increased morbidity and mortality. More frequent and longer HD has been associated with improvement in hyperphosphatemia that may improve outcomes.

STUDY DESIGN

Systematic review and meta-analysis to inform the clinical practice guideline on intensive dialysis for the Canadian Society of Nephrology.

SETTING & POPULATION

Adult patients receiving outpatient long (≥5.5 hours/session; 3-4 times per week) or long-frequent (≥5.5 hours/session, ≥5 sessions per week) HD.

SELECTION CRITERIA FOR STUDIES

We included clinical trials, cohort studies, case series, case reports, and systematic reviews.

INTERVENTIONS

Dialysate calcium concentration ≥1.5 mmol/L and/or phosphate additive.

OUTCOMES

Fragility fracture, peripheral arterial and coronary artery disease, calcific uremic arteriolopathy, mortality, intradialytic hypotension, parathyroidectomy, extraosseous calcification, markers of mineral metabolism, diet liberalization, phosphate-binder use, and muscle mass.

RESULTS

21 studies were identified: 2 randomized controlled trials, 2 reanalyses of data from the randomized controlled trials, and 17 observational studies. Dialysate calcium concentration ≥1.5 mmol/L for patients treated with long and long-frequent HD prevents an increase in parathyroid hormone levels and a decline in bone mineral density without causing harm. Both long and long-frequent HD were associated with a reduction in serum phosphate level of 0.42-0.45 mmol/L and a reduction in phosphate-binder use. There was no direct evidence to support the use of a dialysate phosphate additive.

LIMITATIONS

Almost all the available information is related to changes in laboratory values and surrogate outcomes.

CONCLUSIONS

Dialysate calcium concentration ≥1.5 mmol/L for most patients treated with long and long-frequent dialysis prevents an increase in parathyroid hormone levels and decline in bone mineral density without increased risk of calcification. It seems prudent to add phosphate to the dialysate for patients with a low predialysis phosphate level or very low postdialysis phosphate level until more evidence becomes available.

A successful term pregnancy using in-center intensive quotidian hemodialysis

A 30-year-old woman with stage V chronic kidney disease presented at 7 weeks gestation. She had no uremic symptoms; however, blood urea nitrogen (BUN) was 33.6 mg/dL. Because of the well-established negative relationship between BUN and fetal outcomes, dialysis was initiated with a nocturnal home hemodialysis (NHD)-like prescription performed in-center for logistical reasons. She received 36 hours per week of dialysis. Following the initiation of renal replacement therapy, the predialysis BUN was within the normal physiologic range. The patient had an uncomplicated pregnancy with delivery of a healthy 3000 g infant at 39 weeks gestation. This case adds to the growing literature that supports more intensive dialysis in the pregnant women than was previously recommended. This dose of dialysis should be offered to women in an in-center setting if nocturnal home hemodialysis is not available or feasible.

Intensive hemodialysis associates with improved survival compared with conventional hemodialysis

Patients undergoing conventional maintenance hemodialysis typically receive three sessions per week, each lasting 2.5-5.5 hours. Recently, the use of more intensive hemodialysis (>5.5 hours, three to seven times per week) has increased, but the effects of these regimens on survival are uncertain. We conducted a retrospective cohort study to examine whether intensive hemodialysis associates with better survival than conventional hemodialysis. We identified 420 patients in the International Quotidian Dialysis Registry who received intensive home hemodialysis in France, the United States, and Canada between January 2000 and August 2010. We matched 338 of these patients to 1388 patients in the Dialysis Outcomes and Practice Patterns Study who received in-center conventional hemodialysis during the same time period by country, ESRD duration, and propensity score. The intensive hemodialysis group received a mean (SD) 4.8 (1.1) sessions per week with a mean treatment time of 7.4 (0.87) hours per session; the conventional group received three sessions per week with a mean treatment time of 3.9 (0.32) hours per session. During 3008 patient-years of follow-up, 45 (13%) of 338 patients receiving intensive hemodialysis died compared with 293 (21%) of 1388 patients receiving conventional hemodialysis (6.1 versus 10.5 deaths per 100 person-years; hazard ratio, 0.55 [95% confidence interval, 0.34-0.87]). The strength and direction of the observed association between intensive hemodialysis and improved survival were consistent across all prespecified subgroups and sensitivity analyses. In conclusion, there is a strong association between intensive home hemodialysis and improved survival, but whether this relationship is causal remains unknown.

Patient and technique survival among a Canadian multicenter nocturnal home hemodialysis cohort

BACKGROUND AND OBJECTIVES

As a result of improved clinical and quality-of-life outcomes compared with conventional hemodialysis, interest in nocturnal home hemodialysis (NHD) has steadily increased in the past decade; however, little is known about the flow of patients through NHD programs or about patient-specific predictors of mortality or technique failure associated with this modality. This study addressed this gap in knowledge.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This study included 247 NHD patients of the Canadian Slow Long nightly ExtEnded dialysis Programs (CAN-SLEEP) cohort from 1994 through 2006 inclusive. The association between program- and patient-specific variables and risk for adverse outcomes was determined using uni- and multivariable Cox regression.

RESULTS

A total of 14.6% of the cohort experienced death or technique failure. Unadjusted 1- and 5-year adverse event-free survival was 95.2 and 80.1%, respectively. Significant predictors of a composite of mortality and technique failure included advanced age (P < 0.001), diabetes (P < 0.001), central venous catheter use (P = 0.01), and inability to perform NHD independently (P = 0.009) and were adjusted for center effect. Weekly frequency of NHD was not predictive. Age and diabetes remained significant with multivariable analysis (hazard ratio 1.07 and 2.64, respectively). Unadjusted 1- and 5-year technique survival was 97.9 and 95.2%, respectively. Only age was a significant predictor of technique failure.

CONCLUSIONS

NHD is associated with excellent adverse event-free survival. This study underscores the importance of modality-specific predictors in the success of home hemodialysis, as well as favorable baseline characteristics such as younger age and the absence of diabetes.

Intensifying renal replacement therapy during pregnancy: the role for nocturnal home hemodialysis

Fertility among women receiving conventional hemodialysis or peritoneal dialysis is very low. For those able to conceive it appears that infant survival is poor, and prematurity and its related complications are still commonplace. Nocturnal hemodialysis (NHD) is a form of intensive, self-administered hemodialysis whereby patients receive 3-4 times the duration of conventional hemodialysis resulting in superior removal of uremic toxins compared to traditional dialysis modalities. NHD has been associated with increased fertility, infants with higher birth weights born at more advanced gestational ages, and fewer maternal and fetal complications. These encouraging results suggest a greater role for much more intensive dialysis in pregnancy.

Nocturnal home hemodialysis and short daily hemodialysis compared with kidney transplantation: emerging data in a new era

Nocturnal home hemodialysis (NHD) and short daily hemodialysis (SDHD) are novel forms of renal replacement therapies gaining increased attention because of the reversal of many end-stage renal disease (ESRD)-associated pathophysiological perturbations that are not correctable with conventional dialysis. New evidence suggests that such intensive dialysis is associated with improved survival compared with traditional 3-times-a-week hemodialysis and may have a survival advantage comparable to that seen with deceased donor transplantation. If confirmed, these new findings have significant implications for the delivery of care to the ESRD population and warrant further study.

The evaluation of a successful home hemodialysis program: establishing a prospective framework for quality

A mounting body of clinical data and purported quality of life benefits has been primarily responsible for a renewed interest in programs providing longer more frequent home hemodialysis. As novel forms of home hemodialysis (HHD) like nocturnal (nightly) home hemodialysis (NHD) move from strictly the academic "experimental" arenas to potentially the preferred renal replacement modality for patients, it will be necessary for programs to plan and evaluate standardized metrics for program quality. This will be essential for smaller, less experienced centers to gauge their outcomes against larger, more established programs. Driven by market forces primarily in the United States, conventional hemodialysis programs have begun to explore optimal strategies for reporting quality of care in their respective dialysis centers. Extrapolating this to home hemodialysis modalities the question remains which criteria do we use as measures of quality? The evidence is limited to small, observational studies and one small randomized controlled trial. Extrapolating existing quality indices from conventional hemodialysis seems reasonable however may miss many of the true clinically significant advantages of HHD as a modality. Although definitive evidence does not yet exist for intensive home hemodialysis strategies, clearly clinicians, payers and patients are convinced enough of this approach for programs to justify the expansion of these modalities. We have laid the groundwork for the CANadian Slow Long nightly ExtEnded dialysis Programs (CAN-SLEEP), a multicenter cohort aimed to investigate the clinical and programmatic outcomes of NHD. This will allow for the assessment of numerous outcomes on a global scale for this state-of-the art dialysis modality in the form of a multidimensional programmatic evaluation.

Methodological considerations for research in nocturnal home hemodialysis

Nocturnal hemodialysis (NHD) is a form of frequent, intensive renal replacement therapy, which has been suggested to offer multiple physiological benefits over conventional hemodialysis (CHD). Though the evidence supporting these advantages is steadily increasing, significant methodological challenges exist in conducting research in this area. Our review highlights these important considerations and potential biases within the present NHD literature and suggests future research opportunities.

Transplantation in the face of severe donor sepsis: pushing the boundaries?

Most current transplantation guidelines suggest that bacteremia or bacterial sepsis precludes organ donation. However, various investigators report good outcomes when donor bacteremia was discovered incidentally posttransplant or when bacteremia was cleared before organ retrieval. The authors present the case of a donor who underwent surgical repair of a congenital heart defect complicated by refractory septic shock with positive blood cultures for cloxacillin-sensitive Staphylococcus aureus until time of death. Hemorrhagic and necrotic foci were noted on the renal capsules at time of organ retrieval. The donor liver appeared grossly unremarkable. One year after transplantation, the 3 recipients continue to do well with no known sequelae of having received organs from a Staphylococcus aureus -septic donor. The authors conclude that with appropriate perioperative antibiotics targeted at an organism with known sensitivities and consideration of a modified immunosuppressive protocol, even organs from individuals with known severe sepsis at the time of retrieval may be appropriate for donation.

Resting energy expenditure and plasma leptin levels in anorexia nervosa during acute refeeding

OBJECTIVE

To examine changes in plasma leptin levels and resting energy expenditure (REE) during short-term refeeding of patients with anorexia nervosa (AN).

METHOD

This was a longitudinal study of 21 women meeting the DSM-IV criteria for AN who were admitted to the hospital for renutrition. Height, weight, percent body fat (assessed by skin fold thickness), REE (measured by indirect calorimetry), and circulating plasma leptin concentration were assessed at the time of admission and 7 days later.

RESULTS

Over the course of 1 week of refeeding, body mass index (BMI) increased 0.75 +/- 0.15 kg/m(2) (p <.0001), body fat increased 0.9 +/- 0.2% (p <.0001), and REE increased 107 +/- 33 kcal/24 hr (p =.0037). The change in mean leptin levels was not statistically significant (0.45 +/- 0.44 ng/ml; p =.32).

DISCUSSION

Leptin is unlikely responsible for the increase in REE observed with short-term refeeding.

Role of glucose in chronic desensitization of isolated rat islets and mouse insulinoma (betaTC-3) cells to glucose-dependent insulinotropic polypeptide

It is well documented that the release of insulin from isolated perifused islets attenuates over time, despite a continued glucose stimulation. In the current study we have shown that potentiation of insulin release by the intestinal hormone glucose-dependent insulinotropic polypeptide (GIP) is also attenuated after its continuous application. In less than 20 h of maintained stimulus with either hyperglycaemia (11.0 mM glucose) or GIP (10 nM) under hyperglycaemic conditions, insulin release returned to basal values. This was not due to loss of islet viability or reduction in the releasable pool of insulin granules, as 1 mM isobutylmethylxanthine was able to stimulate equivalent insulin release under both conditions. Further examination of chronic GIP desensitization was examined in cultured mouse insulinoma (betaTC-3) cells. GIP-stimulated cAMP production was not greatly affected by the prevailing glucose conditions, suggesting that the glucose dependence of GIP-stimulated insulin release occurs distally to the increase in intracellular cAMP in betaTC-3 cells. The GIP-stimulated cAMP response curve after desensitization was of similar magnitude at all glucose concentrations, but GIP pretreatment did not affect forskolin-stimulated cAMP production. Desensitization of the cAMP response in betaTC-3 cells was shown not to involve induction of dipeptidyl peptidase IV or pertussis toxin-sensitive G-proteins, activation of protein kinase C or protein kinase A, or modulation of phosphodiesterase activity. Homologous desensitization of the insulin-potentiating activity of GIP was found to affect both GIP-stimulated and forskolin-stimulated insulin release, indicating desensitization of distal steps in the stimulus-exocytosis cascade.

Body fat, caloric intake, and plasma leptin levels in women with anorexia nervosa

OBJECTIVE

To measure serum leptin concentrations in women with anorexia nervosa (AN) and to identify independent predictors of leptin levels, thereby allowing hormone levels to be modeled using regression analysis.

METHODS

A cross-sectional study of 15 AN inpatients and 16 healthy control subjects. Age, height, weight, percent body fat, total caloric intake, fat intake, and fasting plasma leptin levels were recorded. Stepwise forward regression analysis was carried out to identify predictors of leptin levels.

RESULTS

Circulating leptin concentrations in AN were 3.5+/-0.5 versus 7.6+/-1.2 ng/ml in control subjects. Percent body fat correlated best with leptin levels in anorexic and control subjects (r =.63; p =.0002), with caloric intake showing only a moderate correlation (r = .47; p = .008). Only percent body fat was a significant predictor of plasma leptin levels in our regression model.

DISCUSSION

Leptin levels are proportionately lower in AN as compared to healthy controls. It appears that physiological regulation of plasma levels with respect to percent body fat is maintained in individuals with little body fat.

Improved glucose tolerance in rats treated with the dipeptidyl peptidase IV (CD26) inhibitor Ile-thiazolidide

The incretins glucose-dependent insulinotropic polypeptide (GIP1-42) and truncated forms of glucagon-like peptide-1 (GLP-1) are hormones released from the gut in response to ingested nutrients, which act on the pancreas to potentiate glucose-induced insulin secretion. These hormones are rapidly inactivated by the circulating enzyme dipeptidyl peptidase IV ([DPIV] CD26). This study describes the effect on glucose tolerance and insulin secretion of inhibiting endogenous DPIV in the rat using Ile-thiazolidide, a specific DPIV inhibitor. High-performance liquid chromatography (HPLC) analysis of plasma following in vivo administration of 125I-labeled peptides showed that inhibition of DPIV by about 70% prevented the degradation of 90.0% of injected 125I-GLP-17-36 after 5 minutes, while only 13.4% remained unhydrolyzed in rats not treated with the DPIV-inhibiting agent after only 2 minutes. Ile-thiazolidide treatment also increased the circulating half-life of intact GLP-17-36 released in response to intraduodenal (ID) glucose (as measured by N-terminal specific radioimmunoassay [RIA]). In addition, inhibition of DPIV in vivo resulted in an earlier increase and peak of plasma insulin and a more rapid clearance of blood glucose in response to ID glucose challenge. When considered with the HPLC data, these results suggest that the altered insulin profile is an incretin-mediated response. DPIV inhibition resulting in improved glucose tolerance may have therapeutic potential for the management of type 2 diabetes mellitus.

Improved glucose tolerance in Zucker fatty rats by oral administration of the dipeptidyl peptidase IV inhibitor isoleucine thiazolidide

The hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide (GLP)-1 act on the pancreas to potentiate glucose-induced insulin secretion (enteroinsular axis). These hormones (incretins) are rapidly hydrolyzed by the circulating enzyme dipeptidyl peptidase IV (DP IV) into biologically inactive NH2-terminally truncated fragments. This study describes the effect of inhibiting endogenous DP IV with a specific DP IV inhibitor, isoleucine thiazolidide (Ile-thiazolidide), on glucose tolerance and insulin secretion in the obese Zucker rat. In initial studies, the specificity of Ile-thiazolidide as an inhibitor of incretin degradation was determined using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. These results showed that inhibiting DP IV activity with Ile-thiazolidide blocked the formation of NH2-terminally truncated GIP and GLP-1. Oral administration of Ile-thiazolidide resulted in rapid inhibition of circulating DP IV levels by 65% in obese and lean Zucker rats. Suppression of DP IV levels enhanced insulin secretion in both phenotypes with the most dramatic effect occurring in obese animals (150% increase in integrated insulin response vs. 27% increase in lean animals). Ile-thiazolidide treatment improved glucose tolerance in both phenotypes and restored glucose tolerance to near-normal levels in obese animals. This was attributed to the glucose-lowering actions of increasing the circulating half-lives of the endogenously released incretins GIP and, particularly, GLP-1. This study suggests that drug manipulation of plasma incretin activity by inhibiting the enzyme DP IV is a valid therapeutic approach for lowering glucose levels in NIDDM and other disorders involving glucose intolerance.

Investigation of glucose-dependent insulinotropic polypeptide-(1-42) and glucagon-like peptide-1-(7-36) degradation in vitro by dipeptidyl peptidase IV using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. A novel kinetic approach

The incretins glucose-dependent insulinotropic polypeptide (GIP1-42) and glucagon-like peptide-1-(7-36)-amide (GLP-17-36), hormones that potentiate glucose-induced insulin secretion from the endocrine pancreas, are substrates of the circulating exopeptidase dipeptidyl peptidase IV and are rendered biologically inactive upon cleavage of their N-terminal dipeptides. This study was designed to determine if matrix-assisted laser desorption/ionization-time of flight mass spectrometry is a useful analytical tool to study the hydrolysis of these hormones by dipeptidyl peptidase IV, including kinetic analysis. Spectra indicated that serum-incubated peptides were cleaved by this enzyme with only minor secondary degradation due to other serum protease activity. Quantification of the mass spectrometric signals allowed kinetic constants for both porcine kidney- and human serum dipeptidyl peptidase IV-catalyzed incretin hydrolysis to be calculated. The binding constants (Km) of these incretins to purified porcine kidney-derived enzyme were 1.8 +/- 0.3 and 3.8 +/- 0.3 microM, whereas the binding constants observed in human serum were 39 +/- 29 and 13 +/- 9 microM for glucose-dependent-insulinotropic polypeptide and glucagon-like peptide-1-(7-36)-amide respectively. The large range of Km values found in human serum suggests a heterogeneous pool of enzyme. The close correlation between the reported kinetic constants and those previously described validates this novel approach to kinetic analysis.