Pierre Antoine Brown

Complications and catheter survival with prolonged embedding of peritoneal dialysis catheters

BACKGROUND Our centre uses a modification of the Moncrief technique of embedding peritoneal dialysis (PD) catheters. We undertook this study to test the hypothesis that catheter survival on PD is a function of the time a catheter is left embedded prior to use. METHODS Data were retrospectively abstracted from review of patient records of those who received a first PD catheter over a 5-year period. Patients were divided into tertiles based on the number of days between insertion of the catheter and exteriorization to create three equal groups representing early (group 1, 11-47 days), mid (group 2, 48-133 days) and late (group 3, 134-2041 days) exteriorization strategies. RESULTS 435 embedded PD catheters were inserted, 349 were exteriorized and total observation period was 5624 patient-months. Time to catheter loss was shortest in group 1 and longest in group 2 (P = 0.04). The overall rate of primary catheter failure was 6% and was significantly different in the three groups (6.9% in group 1, 1.7% in group 2 and 9.4% in group 3, P = 0.04). The time to first episode of peritonitis was longest in group 3 and shortest in group 1 (group 1 versus group 3, P = 0.009; group 2 versus group 3, P = 0.03). Adjusted peritonitis rates, however, were not different between the three groups. CONCLUSIONS Mechanical complications and catheter loss are associated with the length of time a catheter is embedded. We recommend insertion 6 weeks to 5 months ahead of the need for PD to maximize catheter survival.

Granulocyte-macrophage colony-stimulating factor as an immune-based therapy in HIV infection.

The HIV/AIDS epidemic continues to spread despite more than 20 years of significant research and major advances in its treatment. The introduction of highly active antiretroviral therapy in recent years has significantly improved disease treatment with a dramatic impact in HIV/AIDS associated morbidity and mortality in countries which have access to this therapy. Despite these advances, such therapies are imperfect and other therapeutic modalities, including immune-based therapies, are being actively sought. Potential benefits of immune-based therapies include: 1) the improvement of HIV-specific immunity to enhance control of viral replication, 2) the improvement of other aspects of host immunity in order to prevent or delay the development of opportunistic infections and 3) the potential to purge virus from cellular reservoirs which are sustained despite the effects of potent antiretroviral therapy. Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been studied as one of these immune-based therapies. Several randomized, controlled trials have demonstrated benefits of using GM-CSF as an adjunct to conventional anti-retroviral therapy, although such benefits have not been universally observed. Individual studies have shown that GM-CSF increases CD4+ T cells counts and may be associated with decreased plasma HIV RNA levels. There is limited evidence that GM-CSF may help prevent the emergence of antiretroviral drug resistant viruses and that it may decrease the risk of infection in advanced HIV disease. Despite its high costs and the need to be administered subcutaneously, encouraging results continue to emerge from further studies, suggesting that GM-CSF has the potential to become an effective agent in the treatment of HIV infection.

Factors Associated with Unplanned Dialysis Starts in Patients followed by Nephrologists: A Retropective Cohort Study

The number of patients starting dialysis is increasing world wide. Unplanned dialysis starts (patients urgently starting dialysis in hospital) is associated with increased costs and high morbidity and mortality. Risk factors for starting dialysis urgently in hospital have not been well studied. The primary objective of this study was to identify risk factors for unplanned dialysis starts in patients followed in a multidisciplinary chronic kidney disease (CKD) clinic. We performed a retrospective cohort study of 649 advanced CKD patients followed in a multidisciplinary CKD clinic at a tertiary care hospital from January 01, 2010 to April 30, 2013. Patients were classified as unplanned start (in hospital) or elective start. Multivariable logistic regression was used to identify variables associated with unplanned dialysis initiation. 184 patients (28.4%) initiated dialysis, of which 76 patients (41.3%) initiated dialysis in an unplanned fashion and 108 (58.7%) starting electively. Unplanned start patients were more likely to have diabetes (68.4% versus 51.9%; p = 0.04), CAD (42.1% versus 24.1%; p = 0.02), congestive heart failure (36.8% versus 17.6%; p = 0.01), and were less likely to receive modality education (64.5% vs 89.8%; p < 0.01) or be assessed by a surgeon for access creation (40.8% vesrus78.7% p < 0.01). On multivariable analysis, higher body mass index (OR 1.07, 95% CI 1.02, 1.13), and a history of congestive heart failure (OR 2.41, 95% CI 1.09, 5.41) were independently associated with an unplanned start. Unplanned dialysis initiation is common among advanced CKD patients, even if they are followed in a multidisciplinary chronic kidney disease clinic. Timely education and access creation in patients at risk may lead to lower costs and less morbidity and mortality.

Utilizing Estimated Creatinine Excretion to Improve the Performance of Spot Urine Samples for the Determination of Proteinuria in Kidney Transplant Recipients.

Background Agreement between spot and 24-hour urine protein measurements is poor in kidney transplant recipients. We investigated whether using formulae to estimate creatinine excretion rate (eCER), rather than assuming a standard creatinine excretion rate, would improve the estimation of proteinuria from spot urine samples in kidney transplant recipients. Methods We measured 24 hour urine protein and albumin and spot albumin:creatinine (ACR) and spot protein:creatinine (PCR) in 181 Kidney transplant recipients.” We utilized 6 different published formulae (Fotheringham, CKD-EPI, Cockcroft-Gault, Walser, Goldwasser and Rule) to estimate eCER and from it calculated estimated albumin and protein excretion rate (eAER and ePER). Bias, precision and accuracy (within 15%, 30% and 50%) of ACR, PCR, eAER, ePER were compared to 24-hour urine protein and albumin. Results ACR and PCR significantly underestimated 24-hour albumin and protein excretion (ACR Bias (IQR), -5.9 mg/day; p< 0.01; PCR Bias, (IQR), -35.2 mg/day; p<0.01). None of the formulae used to calculate eAER or ePER had a bias that was significantly different from the 24-hour collection (eAER and ePER bias: Fotheringham -0.3 and 7.2, CKD-EPI 0.3 and 13.5, Cockcroft-Gault -3.2 and -13.9, Walser -1.7 and 3.1, Goldwasser -1.3 and -0.5, Rule -0.6 and 4.2 mg/day respectively. The accuracy for ACR and PCR were lower (within 30% being 38% and 43% respectively) than the corresponding values estimated by utilizing eCER (for eAER 46% to 49% and ePER 46–54%). Conclusion Utilizing estimated creatinine excretion to calculate eAER and ePER improves the estimation of 24-hour albuminuria/proteinuria with spot urine samples in kidney transplant recipients.

Individual patient variability with the application of the kidney failure risk equation in advanced chronic kidney disease.

The Kidney Failure Risk Equation (KFRE) predicts the need for dialysis or transplantation using age, sex, estimated glomerular filtration rate (eGFR), and urine albumin to creatinine ratio (ACR). The eGFR and ACR have known biological and analytical variability. We examined the effect of biological and analytical variability of eGFR and ACR on the 2-year KFRE predicted kidney failure probabilities using single measure and the average of repeat measures of simulated eGFR and ACR. Previously reported values for coefficient of variation (CV) for ACR and eGFR were used to calculate day to day variability. Variation was also examined with outpatient laboratory data from patients with an eGFR between 15 and 50 mL/min/1.72 m2. A web application was developed to calculate and model day to day variation in risk. The biological and analytical variability related to ACR and eGFR lead to variation in the predicted probability of kidney failure. A male patient age 50, ACR 30 mg/mmol and eGFR 25, had a day to day variation in risk of 7% (KFRE point estimate: 17%, variability range 14% to 21%). The addition of inter laboratory variation due to different instrumentation increased the variability to 9% (KFRE point estimate 17%, variability range 13% to 22%). Averaging of repeated measures of eGFR and ACR significantly decreased the variability (KFRE point estimate 17%, variability range 15% to 19%). These findings were consistent when using outpatient laboratory data which showed that most patients had a KFRE 2-year risk variability of ≤ 5% (79% of patients). Approximately 13% of patients had variability from 5–10% and 8% had variability > 10%. The mean age (SD) of this cohort was 64 (15) years, 36% were females, the mean (SD) eGFR was 32 (10) ml/min/1.73m2 and median (IQR) ACR was 22.7 (110). Biological and analytical variation intrinsic to the eGFR and ACR may lead to a substantial degree of variability that decreases with repeat measures. Use of a web application may help physicians and patients understand individual patient’s risk variability and communicate risk (https://mccudden.shinyapps.io/kfre_app/). The web application allows the user to alter age, gender, eGFR, ACR, CV (for both eGFR and ACR) as well as units of measurements for ACR (g/mol versus mg/g).

Safety Lapses Prior to Initiation of Hemodialysis for Acute Kidney Injury in Hospitalized Patients: A Patient Safety Initiative

Background: Safety lapses in hospitalized patients with acute kidney injury (AKI) may lead to hemodialysis (HD) being required before renal recovery might have otherwise occurred. We sought to identify safety lapses that, if prevented, could reduce the need for unnecessary HD after AKI; Methods: We conducted a retrospective observational study that included consecutive patients treated with HD for AKI at a large, tertiary academic center between 1 September 2015 and 31 August 2016. Exposures of interest were pre-specified iatrogenic processes that could contribute to the need for HD after AKI, such as nephrotoxic medication or potassium supplement administration. Other outcomes included time from AKI diagnosis to initial management steps, including Nephrology referral; Results: After screening 344 charts, 80 patients were included for full chart review, and 264 were excluded because they required HD within 72 h of admission, were deemed to have progression to end-stage kidney disease (ESKD), or required other renal replacement therapy (RRT) modalities in critical care settings such as continuous renal replacement therapy (CRRT) or sustained low efficiency dialysis (SLED). Multiple safety lapses were identified. Sixteen patients (20%) received an angiotensin converting enzyme inhibitor or angiotensin receptor blocker after AKI onset. Of 35 patients with an eventual diagnosis of pre-renal AKI due to hypovolemia, only 29 (83%) received a fluid bolus within 24 h. For 28 patients with hyperkalemia as an indication for starting HD, six (21%) had received a medication associated with hyperkalemia and 13 (46%) did not have a low potassium diet ordered. Nephrology consultation occurred after a median (IQR) time after AKI onset of 3.0 (1.0–5.7) days; Conclusions: Although the majority of patients had multiple indications for the initiation of HD for AKI, we identified many safety lapses related to the diagnosis and management of patients with AKI. We cannot conclude that HD initiation was avoidable, but, improving safety lapses may delay the need for HD initiation, thereby allowing more time for renal recovery. Thus, development of automated processes not only to identify AKI at an early stage but also to guide appropriate AKI management may improve renal recovery rates.

Implementation and evaluation of structured nephrology morbidity and mortality conferences: a quality education report

AbstractBackgroundMorbidity and Mortality Conferences (M&MCs) have for generations been part of the education of physicians, yet their effectiveness remains questionable. The Ottawa M&M Model (OM3) was developed to provide a structured approach to M&MCs in order to maximize the quality improvement impact of such rounds.Study designWe conducted a retrospective assessment of the impact of implementing nephrology-specific M&MCs using the OM3. Setting and participantsAll physicians, residents and fellows from the division of nephrology at a large academic medical center were invited to participate.Quality improvement planStructured M&MCs were implemented to identify preventable errors and generate actions to improve quality of care and patient safety.OutcomesNumber and nature of cases reviewed, number and nature of recommendations generated through identification of preventable health system and/or cognitive factors.MeasurementsMorbidity and/or mortality in each case were identified. A determination of the underlying factors and preventability of these events was made. A qualitative review of resulting recommendations was performed.ResultsOver the course of sixteen 1-h long conferences, 52 cases were presented. For all cases presented, discussion, action items and information dissemination followed the OM3. As a result of the M&MCs, 29 recommendations (emanating from 27 cases) lead to improve care delivery.LimitationsLimitations of this study include its retrospective nature and single-center design.ConclusionsThe implementation of regularly scheduled M&MCs at an academic nephrology program, using a structured model, identified preventable health-systems issues and cognitive errors. Approximately one-half of the cases reviewed generated actions for health care delivery improvement.

The Risk of Adverse Events in Patients With Polycystic Kidney Disease With Advanced Chronic Kidney Disease

Background: Polycystic kidney disease (PKD) leads to progressive chronic kidney disease (CKD) with a subsequent risk of adverse events such as cardiac disease, infections, end-stage kidney disease (ESKD), and mortality. Objectives: To determine the risks of CKD-related adverse outcomes in patients with PKD compared with patients without PKD. Setting: Canadian study of prediction of death, dialysis and interim cardiovascular events (CanPREDDICT) was a prospective pan-Canadian cohort study from 2008-2013 involving 28 facilities with adjudicated outcomes. Patients: Adult CKD patients (estimated glomerular filtration rate [eGFR] = 15-45 mL/min/1.73 m2) under the care of a nephrologist. Measurements: Polycystic kidney disease as identified by the treating physician. Methods: Patients with PKD (PKD) and non-PKD were propensity score (PS) matched (1:4) using demographics, comorbidities, and laboratory values. We used conditional Cox proportional hazards models to examine the risk of cardiac disease (defined as coronary artery disease or congestive heart failure), infection, ESKD, or all-cause mortality in patients with PKD compared with no PKD. Results: Among a total of 2370 patients, 105 with PKD were matched with 416 without PKD with a baseline mean age and eGFR of 62.6 years and 27.8 mL/min, respectively. During 1680 person-years of follow time (median follow-up: 3.8 years), there were a total of 43 cardiac, 83 ESKD, 117 infectious, and 39 all-cause mortality events. PKD was associated with a higher risk of cardiac events (9.5% vs 7.9%, hazard ratio [HR] = 1.46, 95% confidence interval [CI] = 1.04-2.04) and ESKD (25.7% vs 13.5%, HR = 2.00, 95% CI = 1.33-3.01), and with similar risks for infection (21.9% vs 22.6%, HR = 1.16, 95% CI = 0.75-1.82) or all-cause mortality (6.7% vs 7.7%, HR = 0.87, 95% CI = 0.40-1.91) compared with non-PKD. There were no differences in the types of infections (urinary, respiratory, hematologic, or other) between the 2 groups (P = .585). Conclusions: Patients with PKD with advanced CKD are at a potentially higher risk of ESKD and cardiac events compared with patients without PKD. These findings, if confirmed in larger cohorts, suggest that monitoring and treatment for adverse outcomes in patients with PKD, especially related to cardiac disease, may be beneficial.

Hemodialysis Access Choice: Impact of Health Literacy

Background: Hemodialysis patients need to make decisions about vascular access and diet that they may not fully understand. In this study, we hypothesized that patients with low health literacy are likely to choose a central venous catheter (CVC) and have higher serum potassium (K), serum phosphate (P), and inter-dialysis weight gains (IDWG). Objective: Primarily, the study sought to describe the health literacy of patients treated with hemodialysis in a Canadian tertiary care center. The secondary objective was to describe the association between health literacy and permanent vascular access choice, hyperkalemia, hyperphosphatemia, and IDWG. Methods: Adult patients receiving hemodialysis for more than 6 months were included. Health literacy was assessed with the Newest Vital Sign (NVS) test. Vascular access type and reasons for CVC use were determined. Serum K, P, and IDWG were collected retrospectively for 6 months. Students t test and logistic regression were used to determine the association between health literacy (NVS score < 4 versus ≥ 4) and CVC choice, hyperkalemia, hyperphosphatemia, and high IDWG. Key Results: Fifty-six patients were involved. The average NVS score was 2.9. Overall, 66% of the patients had a CVC; one-third had chosen this access themselves. Poor control of K, P, and IDWG was experienced by 27%, 55%, and 36% of patients, respectively. The average NVS score was lower for patients choosing a CVC (p = .001), but not different for those with higher K, P, or IDWG. None of the patients who chose a CVC had adequate health literacy (NVS ≥ 4). Conclusions: Patients with low health literacy, who are eligible for both surgically created vascular access (fistula or graft) and CVC, are more likely to refuse fistula/graft creation compared to patients with adequate health literacy. Different educational strategies for such patients may help in appropriate decision-making. [Health Literacy Research and Practice. 2017;1(3):e136–e144.] Plain Language Summary: This study suggests that more than one-half of patients who receive hemodialysis may not understand all the information provided by their health care team. Despite a higher risk of complications with a central venous catheter, patients with lower health literacy prefer the catheter over fistula as their blood access for hemodialysis. We need to explore patient education to ensure that information is easy to understand.

Are There Any Solutions to the Problem of Declining Nephrology Enrolment? A Dialogue Between Two Practicing Nephrologists

Nephrology, the study of kidney diseases, took its birth as a separate specialty many decades ago, and has gradually more in importance, especially with the advent of renal replacement therapy and kidney transplantation. Nephrology also has a strong physiology foundation; indeed an understanding of renal physiology is crucial for dealing with electrolyte and acid-base problems that a physician commonly faces in day-to-day practice. Perhaps this is why it comes as a surprise that the interest in nephrology fellowships is declining - at least in North America. In this article, we present a dialogue between two practicing nephrologists, working at a tertiary care academic Canadian centre, on some potential solutions to this problem.