Peritoneal dialysis for acute kidney injury

Lower-Dosage Acute Peritoneal Dialysis versus Acute Intermittent Hemodialysis in Acute Kidney Injury: A Randomized Controlled Trial

Key Points

The efficacy of acute peritoneal dialysis is still controversial. There was no significant difference in 28-day mortality between acute peritoneal dialysis and intermittent hemodialysis.

Background

Lower delivered dose of acute peritoneal dialysis (PD) in AKI requires less resources but raises concerns regarding adequate solute and water clearance. The relative merits of lower-dose PD versus intermittent hemodialysis remain uncertain.

Methods

A multicenter randomized controlled trial compared the outcomes between acute lower-dosage PD (18–24 L per day) and intermittent hemodialysis (three times per week) from May 2018 to January 2021 in patients with AKI. The primary outcome was 28-day mortality rate. Secondary outcomes included 28-day dialysis-free survival and kidney recovery, metabolic profile, and procedure-related complications. Noninferiority of PD to hemodialysis would be demonstrated if the upper bound of the 95% confidence interval ( CI) on risk difference (PD-hemodialysis) in 28-day mortality rates between the two groups was <20%.

Results

We included 157 patients (80 allocated to PD and 77 to intermittent hemodialysis). Before KRT initiation, baseline clinical characteristics between groups were comparable. The overall mean age was 57±15 years. The most frequent cause of AKI was sepsis (68%). There was no difference in 28-day mortality between acute PD and intermittent hemodialysis (50% versus 49%, risk difference 0.6 [95% CI, −15.0 to 16.3]), and 28-day dialysis-free survival (42% versus 37%, risk difference 4.6 [95% CI, −11.1 to 20.3]). Mean weekly Kt/V urea was 2.11±1.14 and 2.55±1.11 in the PD and intermittent hemodialysis groups, respectively. The 7-day fluid balance of PD and intermittent hemodialysis patients was not significantly different. There was more frequent intradialytic hypotension in the intermittent hemodialysis group and more frequent hypokalemia in the PD group.

Conclusions

In this study of patients with AKI, there was no significant difference in 28-day mortality between acute PD and intermittent hemodialysis.

Acute Kidney Injury Receiving Dialysis and Dialysis Care after Hospital Discharge

The number of patients with AKI receiving outpatient hemodialysis (AKI-D) is increasing. At present, on the basis of limited data, approximately one third of patients with AKI-D who receive outpatient dialysis after hospital discharge survive and regain sufficient kidney function to discontinue dialysis. Data to inform dialysis management strategies that promote kidney function recovery and processes of care among patients with AKI-D receiving outpatient dialysis are lacking. In this article, we detail current trends in the incidence, risk factors, clinical outcomes, proposed management, and health policy landscape for patients with AKI-D receiving outpatient dialysis and identify areas for further research.

Is It Time to Give Peritoneal Dialysis Its Due Place in Managing Acute Kidney Injury: Lessons Learnt from COVID-19 Pandemic

Despite comparable outcomes with the extracorporeal dialysis modalities, peritoneal dialysis (PD) is seldom considered a viable option for managing acute kidney injury (AKI) in developed and resource-rich countries, where continuous renal replacement therapies (CRRTs) are the mainstay of treating AKI. PD has fewer infrastructure requirements and has been shown to save lives during conflicts, natural disasters, and pandemics. During the ongoing COVID-19 pandemic, the developed world was confronted with a sudden surge in critically ill AKI patients requiring renal replacement therapy. There were acute shortages of CRRT machines and the trained staff to deliver those treatments. Some centres developed acute PD programmes to circumvent these issues with good results. This experience re-emphasised the suitability of PD for managing AKI. It also highlighted the need to review the current management strategies for AKI in developed countries and consider incorporating PD as a viable tool for suitable patients. This article reviews the current evidence of using PD in AKI, attempts to clarify some misconceptions about PD in AKI, and argues in favour of developing acute PD programmes.

Peritoneal Dialysis in Critically Ill Patients: Time for a Critical Reevaluation?

Peritoneal dialysis (PD) as an AKI treatment in adults was widely accepted in critical care settings well into the 1980s. The advent of extracorporeal continuous KRT led to widespread decline in the use of PD for AKI across high-income countries. The lack of familiarity and comfort with the use of PD in critical care settings has also led to lack of use even among those receiving maintenance PD. Many critical care units reflexively convert patients receiving maintenance PD to alternative dialysis therapies at admission. Renewed interest in the use of PD for AKI therapy has emerged due to its increasing use in low- and middle-income countries. In high-income countries, the coronavirus disease 2019 (COVID-19) pandemic, saw PD for AKI used early on, where many critical care units were in crisis and relied on PD use when resources for other AKI therapy modalities were limited. In this review, we highlight advantages and disadvantages of PD in critical care settings and indications and contraindications for its use. We provide an overview of literature to support both PD treatment during AKI and its continuation as a maintenance therapy during critical illness. For AKI therapy, we further discuss establishment of PD access, PD prescription management, and complication monitoring and treatment. Finally, we discuss expansion in the use of PD for AKI therapy extending beyond its role during times of resource constraints.

Innovationen in der Peritonealdialyse

Die Peritonealdialyse (PD) war früher eine geläufige Behandlung beim akuten dialysepflichtigen Nierenversagen. Zugunsten kontinuierlicher, extrakorporaler Nierenersatzverfahren verschwand sie von der Bildfläche der westlichen Welt, wohingegen sie in strukturarmen Ländern aufgrund ihrer Simplizität und geringen Ressourcenintensität weiter eingesetzt wird. Die Engpässe in der medizinischen Versorgung im Rahmen der COVID-19(„coronavirus disease 2019“)-Pandemie führten kürzlich zu erneuter weltweiter Beachtung der PD als sichere Option beim akuten dialysepflichtigen Nierenversagen. Von der Einführung biokompatibler Lösungen vor 20 Jahren war eine Reduktion von Mortalität oder technischem Versagen erwartet worden. Leider konnten Studien dieses bisher allenfalls andeuten, nicht aber beweisen. Eine innovative Option stellen immunmodulatorische Adjuvanzien dar, die die lokale Immunkompetenz verbessern und den Verlust der Funktion des Peritoneums verhindern sollen. Derzeit rückt die Vision einer tragbaren künstlichen Niere immer näher. Auch eine Intensivierung der Dialysedosis erscheint mit minimaler Dialysatmenge erreichbar. In Zeiten der globalen Erderwärmung könnten durch die Regeneration von Dialysat nicht nur relevante Mengen an Wasser eingespart, sondern auch die CO₂-Bilanz günstig beeinflusst werden. Zusammenfassend erlebt die PD derzeit einen zweiten Frühling. Dieser Artikel beschreibt die derzeitigen und zukünftigen Entwicklungen dieses Verfahrens.

Renal replacement therapy for critically ill patients with COVID-19-associated acute kidney injury: A review of current knowledge

The outbreak of coronavirus disease 2019 (COVID-19) has rapidly evolved into a global pandemic. A significant proportion of COVID-19 patients develops severe symptoms, which may include acute respiratory distress syndrome and acute kidney injury as manifestations of multi-organ failure. Acute kidney injury (AKI) necessitating renal replacement therapy (RRT) is increasingly prevalent among critically ill patients with COVID-19. However, few studies have focused on AKI treated with RRT. Many questions are awaiting answers as regards AKI in the setting of COVID-19; whether patients with COVID-19 commonly develop AKI, what are the underlying pathophysiologic mechanisms? What is the best evidence regarding treatment approaches? Identification of the potential indications and the preferred modalities of RRT in this context, is based mainly on clinical experience. Here, we review the current approaches of RRT, required for management of critically ill patients with COVID-19 complicated by severe AKI as well as the precautions that should be adopted by health care providers in dealing with these cases. Electronic search was conducted in MEDLINE, PubMed, ISI Web of Science, and Scopus scientific databases. We searched the terms relevant to this review to identify the relevant studies. We also searched the conference proceedings and ClinicalTrials.gov database.

Serum Uric Acid and Cardiovascular or All-Cause Mortality in Peritoneal Dialysis Patients: A Systematic Review and Meta-Analysis

Background: Studies have shown inconsistent associations between serum uric acid (SUA) levels and mortality in peritoneal dialysis (PD) patients. We conducted this meta-analysis to determine whether SUA levels were associated with cardiovascular or all-cause mortality in PD patients.

Methods: PubMed, Embase, Web of Science, the Cochrane Library, CNKI, VIP, Wanfang Database, and trial registry databases were systematically searched up to April 11, 2021. Cohort studies of SUA levels and cardiovascular or all-cause mortality in PD patients were obtained. Random effect models were used to calculate the pooled adjusted hazard ratio (HR) and corresponding 95% confidence interval (CI). Sensitivity analyses were conducted to assess the robustness of the pooled results. Subgroup analyses and meta-regression analyses were performed to explore the sources of heterogeneity. Funnel plots, Begg's tests, and Egger's tests were conducted to evaluate potential publication bias. The GRADE approach was used to rate the certainty of evidence. This study was registered with PROSPERO, CRD42021268739.

Results: Seven studies covering 18,113 PD patients were included. Compared with the middle SUA levels, high SUA levels increased the risk of all-cause mortality (HR = 1.74, 95%CI: 1.26–2.40, I² = 34.8%, τ² = 0.03), low SUA levels were not statistically significant with the risk of all-cause or cardiovascular mortality (HR = 1.04, 95%CI: 0.84–1.29, I² = 43.8%, τ² = 0.03; HR = 0.89, 95%CI: 0.65–1.23, I² = 36.3%, τ² = 0.04; respectively). Compared with the low SUA levels, high SUA levels were not statistically associated with an increased risk of all-cause or cardiovascular mortality (HR = 1.19, 95%CI: 0.59–2.40, I² = 88.2%, τ² = 0.44; HR = 1.22, 95%CI: 0.39–3.85, I² = 89.3%, τ² = 0.92; respectively).

Conclusion: Compared with middle SUA levels, high SUA levels are associated with an increased risk of all-cause mortality in PD patients. SUA levels may not be associated with cardiovascular mortality. More high-level studies, especially randomized controlled trials, are needed to determine the association between SUA levels and cardiovascular or all-cause mortality in PD patients.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021268739, identifier: CRD42021268739.

Polymeric membranes for biomedical applications

The rapid development of nanotechnology paved the way for further expansion of polymer chemistry and the fabrication of advanced polymeric membranes. Such modifications allowed enhancing or adding some unique properties, including mechanical strength, excellent biocompatibility, easily controlled degradability, and biological activity. This chapter discusses various applications of polymeric membranes in three significant areas of biomedicine, including tissue engineering, drug delivery systems, and diagnostics. It is intended to highlight here possible ways of improvement the properties of polymeric membranes, by modifying with other polymers, functional groups, compounds, drugs, bioactive components, and nanomaterials.

Determinants of Outcomes of Acute Kidney Injury: Clinical Predictors and Beyond

Acute kidney injury (AKI) is a common clinical syndrome characterized by rapid impairment of kidney function. The incidence of AKI and its severe form AKI requiring dialysis (AKI-D) has been increasing over the years. AKI etiology may be multifactorial and is substantially associated with increased morbidity and mortality. The outcome of AKI-D can vary from partial or complete recovery to transitioning to chronic kidney disease, end stage kidney disease, or even death. Predicting outcomes of patients with AKI is crucial as it may allow clinicians to guide policy regarding adequate management of this problem and offer the best long-term options to their patients in advance. In this manuscript, we will review the current evidence regarding the determinants of AKI outcomes, focusing on AKI-D.

Acute Peritoneal Dialysis During the COVID-19 Pandemic at Bellevue Hospital in New York City

Background

The COVID-19 pandemic strained hospital resources in New York City, including those for providing dialysis. New York University Medical Center and affiliations, including New York City Health and Hospitals/Bellevue, developed a plan to offset the increased needs for KRT. We established acute peritoneal dialysis (PD) capability, as usual dialysis modalities were overwhelmed by COVID-19 AKI.

Methods

Observational study of patients requiring KRT admitted to Bellevue Hospital during the COVID surge. Bellevue Hospital is one of the largest public hospitals in the United States, providing medical care to an underserved population. There were substantial staff, supplies, and equipment shortages. Adult patients admitted with AKI who required KRT were considered for PD. We rapidly established an acute PD program. A surgery team placed catheters at the bedside in the intensive care unit; a nephrology team delivered treatment. We provided an alternative to hemodialysis and continuous venovenous hemofiltration for treating patients in the intensive-care unit, demonstrating efficacy with outcomes comparable to standard care.

Results

From April 8, 2020 to May 8, 2020, 39 catheters were placed into ten women and 29 men. By June 10, 39% of the patients started on PD recovered kidney function (average ages 56 years for men and 59.5 years for women); men and women who expired were an average 71.8 and 66.2 years old. No episodes of peritonitis were observed; there were nine incidents of minor leaking. Some patients were treated while ventilated in the prone position.

Conclusions

Demand compelled us to utilize acute PD during the COVID-19 pandemic. Our experience is one of the largest recently reported in the United States of which we are aware. Acute PD provided lifesaving care to acutely ill patients when expanding current resources was impossible. Our experience may help other programs to avoid rationing dialysis treatments in health crises.

Acute Peritoneal Dialysis With Percutaneous Catheter Insertion for COVID-19-Associated Acute Kidney Injury in Intensive Care: Experience From a UK Tertiary Center

Introduction

During the coronavirus disease 2019 (COVID-19) pandemic in 2020, high rates of acute kidney injury (AKI) in critically unwell patients are being reported, leading to an increased demand for renal replacement therapy (RRT). Providing RRT for this large number of patients is proving challenging, and so alternatives to continuous renal replacement therapies (CRRT) in the intensive care unit (ICU) are needed. Peritoneal dialysis (PD) can be initiated immediately after percutaneous insertion of the catheter, but there are concerns about impact on ventilation and RRT efficacy. We sought to describe our recent experience with percutaneous catheter insertion and peritoneal dialysis in patients in the ICU with COVID-19 infection.

Method

Patients were selected according to local protocol, and catheters were inserted percutaneously by experienced operators using a Seldinger technique. Sequential Organ Failure Assessment (SOFA) score and ventilation requirements were recorded at the time of insertion and 24 hours later. Procedural complications, proportion of RRT provided by PD, renal recovery, and RRT parameters (serum potassium and maximum base excess) during PD were assessed.

Results

Percutaneous PD catheters were successfully inserted in 37 of 44 patients (84.1%) after a median of 13.5 days (interquartile range [IQR] = 10.0, 20.3 days) in the ICU. No adverse events were reported; SOFA scores and ventilation requirements were comparable before and after insertion; and adequate RRT parameters were achieved. The median proportion of RRT provided by PD following catheter insertion was 94.6% (IQR = 75.0, 100%).

Conclusion

Peritoneal dialysis provides a safe and effective alternative to CRRT in selected patients with AKI and COVID-19 infection requiring ventilation on intensive care.

COVID-19-associated acute kidney injury: consensus report of the 25th Acute Disease Quality Initiative (ADQI) Workgroup

Kidney involvement in patients with coronavirus disease 2019 (COVID-19) is common, and can range from the presence of proteinuria and haematuria to acute kidney injury (AKI) requiring renal replacement therapy (RRT; also known as kidney replacement therapy). COVID-19-associated AKI (COVID-19 AKI) is associated with high mortality and serves as an independent risk factor for all-cause in-hospital death in patients with COVID-19. The pathophysiology and mechanisms of AKI in patients with COVID-19 have not been fully elucidated and seem to be multifactorial, in keeping with the pathophysiology of AKI in other patients who are critically ill. Little is known about the prevention and management of COVID-19 AKI. The emergence of regional 'surges' in COVID-19 cases can limit hospital resources, including dialysis availability and supplies; thus, careful daily assessment of available resources is needed. In this Consensus Statement, the Acute Disease Quality Initiative provides recommendations for the diagnosis, prevention and management of COVID-19 AKI based on current literature. We also make recommendations for areas of future research, which are aimed at improving understanding of the underlying processes and improving outcomes for patients with COVID-19 AKI.

COVID-19-associated acute kidney injury: consensus report of the 25th Acute Disease Quality Initiative (ADQI) Workgroup

Kidney involvement in patients with coronavirus disease 2019 (COVID-19) is common, and can range from the presence of proteinuria and haematuria to acute kidney injury (AKI) requiring renal replacement therapy (RRT; also known as kidney replacement therapy). COVID-19-associated AKI (COVID-19 AKI) is associated with high mortality and serves as an independent risk factor for all-cause in-hospital death in patients with COVID-19. The pathophysiology and mechanisms of AKI in patients with COVID-19 have not been fully elucidated and seem to be multifactorial, in keeping with the pathophysiology of AKI in other patients who are critically ill. Little is known about the prevention and management of COVID-19 AKI. The emergence of regional 'surges' in COVID-19 cases can limit hospital resources, including dialysis availability and supplies; thus, careful daily assessment of available resources is needed. In this Consensus Statement, the Acute Disease Quality Initiative provides recommendations for the diagnosis, prevention and management of COVID-19 AKI based on current literature. We also make recommendations for areas of future research, which are aimed at improving understanding of the underlying processes and improving outcomes for patients with COVID-19 AKI.

Urgent Peritoneal Dialysis in Patients With COVID-19 and Acute Kidney Injury: A Single-Center Experience in a Time of Crisis in the United States

At Montefiore Medical Center in The Bronx, NY, the first case of coronavirus disease 2019 (COVID-19) was admitted on March 11, 2020. At the height of the pandemic, there were 855 patients with COVID-19 admitted on April 13, 2020. Due to high demand for dialysis and shortages of staff and supplies, we started an urgent peritoneal dialysis (PD) program. From April 1 to April 22, a total of 30 patients were started on PD. Of those 30 patients, 14 died during their hospitalization, 8 were discharged, and 8 were still hospitalized as of May 14, 2020. Although the PD program was successful in its ability to provide much-needed kidney replacement therapy when hemodialysis was not available, challenges to delivering adequate PD dosage included difficulties providing nurse training and availability of supplies. Providing adequate clearance and ultrafiltration for patients in intensive care units was especially difficult due to the high prevalence of a hypercatabolic state, volume overload, and prone positioning. PD was more easily performed in non–critically ill patients outside the intensive care unit. Despite these challenges, we demonstrate that urgent PD is a feasible alternative to hemodialysis in situations with critical resource shortages.

Peritoneal dialysis for acute kidney injury

BACKGROUND

Peritoneal dialysis (PD) has been suggested as an effective and safe dialysis modality in patients with acute kidney injury (AKI). However, whether PD is superior to extracorporeal therapy (e.g. haemodialysis) in terms of improving survival, recovery of kidney function, metabolic and clinical outcomes is still inconclusive.

OBJECTIVES

The aim of this review was to evaluate the benefits and harms of PD for patients with AKI compared with extracorporeal therapy or different PD modalities.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies to 29 May 2017 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov. We also searched the China Biological Medicine Database.

SELECTION CRITERIA

We included patients with AKI who were randomised to receive PD, extracorporeal therapy, or different PD modalities regardless of their age, sex, primary disease and clinical course.

DATA COLLECTION AND ANALYSIS

Screening, selection, data extraction and quality assessments for each retrieved article were carried out by two authors using standardised forms. Authors contacted when published data were incomplete. Statistical analyses were performed using the random effects model and results expressed as risk ratio (RR) with 95% confidence intervals (CI). Heterogeneity among studies was explored using the Cochran Q statistic and the I² test. Outcomes of interest included all-cause mortality, recovery of kidney function, weekly delivered Kt/V, correction of acidosis, fluid removal, duration of dialysis, and infectious complications. Confidence in the evidence was assessing using GRADE.

MAIN RESULTS

Six studies (484 participants) met our inclusion criteria. Five studies compared high volume PD with daily haemodialysis, extended daily haemodialysis, or continuous renal replacement therapy. One study focused on the intensity of PD. The overall risk of bias was low to unclear. Compared to extracorporeal therapy, PD probably made little or no difference to all-cause mortality (4 studies, 383 participants: RR 1.12, 95% CI 0.81 to 1.55; I² = 69%; moderate certainty evidence), or kidney function recovery (3 studies, 333 participants: RR 0.95, 95% CI 0.68 to 1.35; I² = 0%; moderate certainty evidence). PD probably slightly reduces the amount of fluid removal compared to extracorporeal therapy (3 studies, 313 participants: MD -0.59 L/d, 95% CI -1.19 to 0.01; I² = 89%; low certainty evidence), and probably made little or no difference to infectious complications (2 studies, 263 participants: RR 1.03, 95% CI 0.60 to 1.78; I² = 0%; low certainty evidence). It is uncertain whether PD compared to extracorporeal therapy has any effects on weekly delivered Kt/V (2 studies, 263 participants: MD -2.47, 95% CI -5.17 to 0.22; I² = 99%; very low certainty evidence), correction of acidosis (2 studies, 89 participants: RR 1.32, 95% CI 0.13 to 13.60; I² = 96%; very low certainty evidence), or duration of dialysis (2 studies, 170 participants: MD -1.01 hours, 95% CI -91.49 to 89.47; I² = 98%; very low certainty evidence). Heterogeneity was high and this may be due to the different extracorporeal therapies used.One study (61 participants) reported little or no difference to all-cause mortality, kidney function recovery, or infection between low and high and intensity PD. Weekly delivered Kt/V and fluid removal was lower with low compared to high intensity PD.

AUTHORS' CONCLUSIONS

Based on moderate (mortality, recovery of kidney function), low (infectious complications), or very low certainty evidence (correction of acidosis) there is probably little or no difference between PD and extracorporeal therapy for treating AKI. Fluid removal (low certainty) and weekly delivered Kt/V (very low certainty) may be higher with extracorporeal therapy.