Remote surveillance technology of dialysis arteriovenous access. Retrospective evaluation in a UK renal centre

BACKGROUND

Early identification of dysfunctional arteriovenous hemodialysis (HD) vascular access (VA) is important for timely referral and intervention.

METHOD

We retrospectively calculated the VA risk score using Vasc-Alert surveillance software technology from HD treatment sessions in 2 satellite HD units over 18 months. We included in the analysis HD patients dialyzing with arteriovenous fistula or graft (AVF/G) with available Vasc-Alert data for≥ 2 months. For group one (eventful) which included patients who developed vascular access thrombosis or stenosis over the study period, we collected Vasc-Alert risk score 2 months prior to the event, and for group two (uneventful) over 5 consecutive months. Vasc-Alert technology utilizes routinely collected data during HD to calculate the VA risk score and triggers an alert if the score is ≥7 in 3 consecutive dialysis sessions. Patients with> 2 alerts (vascular access score ≥ 7) per month were considered to have positive alerts.

RESULTS

From 140 HD patients, 81 patients dialyzed via AVF/G. 77/81 had available Vasc-Alert data and were included in the final analysis. Out of 17 eventful patients, 11 (64.7%) had positive alerts 2 months prior to the vascular event. Out of the 60 patients without vascular events, 20 patients (33.3%) had positive alerts. Vasc-Alert's sensitivity and specificity for vascular events were 64.7% and 66.6% respectively. Within the 6 patients with thrombosed access, 2 patients (33.3%) detected by Vasc-Alert were not detected with clinical monitoring.

CONCLUSION

Vascular access risk score can be a useful non-invasive vascular access surveillance method to assist clinical decision-making.

The epidemiology of primary FSGS including cluster analysis over a 20-year period

INTRODUCTION

Focal segmental glomerulosclerosis (FSGS) is one of the leading causes of nephrotic syndrome in adults. This epidemiological study describes a renal centre's 20-year experience of primary FSGS.

METHODS

Patients were identified with a diagnosis of primary FSGS after exclusion of known secondary causes. In this retrospective observational study, data was collected for baseline demographics, immunosuppression and outcomes. A two-step cluster analysis was used to identify natural groupings within the dataset.

RESULTS

The total cohort was made up of 87 patients. Those who received immunosuppression had lower median serum albumin than those who did not- 23g/L vs 40g/L (p<0.001) and higher median urine protein creatinine ratios (uPCR)- 795mg/mmol vs 318mg/mmol (p <0.001). They were more likely to achieve complete remission (62% vs 40%, p=0.041), but relapsed more 48.6% vs 22% (p=0.027). Overall 5 year mortality was 10.3% and 5 year progression to RRT was seen in 17.2%. Complete remission was observed in 49.4%. The 2-step cluster analysis separated the cohort into 3 clusters: cluster 1 (n=26) with 'nephrotic-range proteinuria'; cluster 2 (n=43) with 'non-nephrotic-range proteinuria'; and cluster 3 (n=18) with nephrotic syndrome. Immunosuppression use was comparable in clusters 1 and 3, but lower in cluster 2 (77.8% and 69.2% vs 11.6%, p<0.001). Rates of complete remission were greatest in clusters 1 and 3 vs cluster 2: 57.7% and 66.7% vs 37.2%.

CONCLUSION

People who received immunosuppression had lower serum albumin and achieved remission more frequently, but were also prone to relapse. Our cluster analysis highlighted 3 FSGS phenotypes: a nephrotic cluster that clearly require immunosuppression; a cohort with preserved serum albumin and non-nephrotic range proteinuria who will benefit from supportive care; and lastly a cluster with heavy proteinuria but serum albumin > 30g/L. This group may still have immune mediated disease and thus could potentially benefit from immunosuppression.

TRIAL REGISTRATION

This study protocol was reviewed and approved by the 'Research and Innovation committee of the Northern Care Alliance NHS Group', study approval number (Ref: ID 22HIP54).

Delivering Personalized, Goal-Directed Care to Older Patients Receiving Peritoneal Dialysis

Background

An aging population living with chronic kidney disease and progressing to kidney failure, subsequently receiving peritoneal dialysis (PD) is growing. A significant proportion of these patients are also living with multi-morbidities and some degree of frailty. Recent practice recommendations from the International Society of Peritoneal Dialysis advocate for high-quality, goal-directed PD prescription, and the Standardized Outcomes of Nephrology-PD initiative emphasized the need for an individualized, goal-based care approach in all patients receiving PD treatment. In older patients, this approach to PD care is even more important. A frailty screening assessment, followed by a comprehensive geriatric assessment (CGA) prior to PD initiation and when dictated by change in relevant circumstances is paramount in tailoring PD care and prescription according to the needs, life goals, as well as clinical status of older patients with kidney failure.

Summary

Our review aimed to summarize the different dimensions to be taken into account when delivering PD care to the older patient - from frailty screening and CGA in older patients receiving PD to employing a personalized, goal-directed PD prescription strategy, to preserving residual kidney function, optimizing blood pressure (BP) control, and managing anemia, to addressing symptom burden, to managing nutritional intake and promoting physical exercise, and to explore telehealth opportunities for the older PD population.

Key Messages

What matters most to older PD patients may not be simply extending survival, but more importantly, to be living comfortably on PD treatment with minimal symptom burden in a home environment and to minimize treatment complications.

Improving outpatient clinic experience: the future of chronic kidney disease care and associated multimorbidity

BACKGROUND

Chronic kidney disease (CKD) is estimated to affect more than 2.5 million adults in England, and this is expected to rise to 4.2 million by 2036 (1). Population-level digital healthcare systems have the potential to enable earlier detection of CKD providing an opportunity to introduce interventions that attenuate progression and reduce the risk of end-stage kidney disease (ESKD) and cardiovascular diseases (CVD). Services that can support patients with CKD, CVD, and diabetes mellitus (DM) have the potential to reduce fragmented clinical care and optimise pharmaceutical management.

METHODS AND RESULTS

The Salford renal service has established an outpatient improvement programme which aims to address these issues via two projects. Firstly, the development of a CKD dashboard that can stratify patients by their kidney failure risk equation (KFRE) risk. High-risk patients would be invited to attend an outpatient clinic if appropriate. Specialist advice and guidance would be offered to primary care providers looking after patients with medium risk. Patients with lower risk would continue with standard care via their primary care provider unless there was another indication for a nephrology referral. The CKD dashboard identified 11546 patients (4.4% of the total adult population in Salford) with T2DM and CKD. The second project is the establishment of the Metabolic CardioRenal (MRC) clinic. It provided care for 209 patients in the first 8 months of its establishment with a total of 450 patient visits. Initial analysis showed clustering of cardiorenal metabolic diseases with 85% having CKD stages 3 and 4 and 73.2% having DM. In addition, patients had a significant burden of CVD with 50.2% having hypertension and 47.8% having heart failure.

CONCLUSION

There is a pressing need to create new outpatient models of care to tackle the rising epidemic of cardio-renal metabolic diseases. This model of service has potential benefits at both organisational and patient levels including improving patient management via risk stratification, increased care capacity and reduction of variation of care. Patients will benefit from earlier intervention, appropriate referral for care, reduction in CKD-related complications, and reduction in hospital visits and cardiovascular events. In addition, this combined digital and patient-facing model of care will allow rapid translation of advances in cardio-renal metabolic diseases into clinical practice.

Peritoneal dialysis-associated peritonitis presenting with Ralstonia pickettii infection: A novel series of three cases during the COVID-19 pandemic

Peritoneal dialysis (PD)-associated peritonitis secondary to Ralstonia infection is very rare. Ralstonia pickettii is an organism that can grow in contaminated saline, water, chlorhexidine, and other medical products used in laboratories and the clinical setting. Infective endocarditis, prosthetic joint, and severe chest infections are previously reported with R. pickettii infection. We report a novel series of three cases diagnosed with PD-associated peritonitis caused by R. pickettii, where the cases appeared consecutively to our unit during a span of 4 weeks. During the COVID-19 pandemic, there were increased uses of non-sterile gloves by clinical staff as a form of personal protective equipment throughout patient interaction and PD exchange, as recommended by local hospital policy for all staff attending to patient care. A multidisciplinary team root cause analysis of our cases suggested non-sterile gloves being the likely source of environmental contamination, leading to PD-associated peritonitis caused by R. pickettii in this scenario.

A low rate of end-stage kidney disease in membranous nephropathy: A single centre study over 2 decades

INTRODUCTION

Membranous nephropathy is the commonest cause of nephrotic syndrome in non-diabetic Caucasian adults over the age of 40 years. Primary membranous nephropathy is limited to the kidneys. Clinical management aims to induce remission, either spontaneously with supportive care, or with immunosuppression. Here, we describe the natural history of this condition in a large tertiary centre in the UK.

METHODS

178 patients with primary membranous nephropathy were identified over 2 decades. We collected data on demographics, baseline laboratory values, treatment received and outcomes including progression to renal replacement therapy and death. Analysis was performed on the whole cohort and specific subgroups. Univariate and multivariate Cox regression was also performed.

RESULTS

Median age was 58.3 years with 63.5% male. Median baseline creatinine was 90μmol/L and urine protein-creatinine ratio 664g/mol. Remission (partial or complete) was achieved in 134 (75.3%), either spontaneous in 60 (33.7%) or after treatment with immunosuppression in 74 (41.6%), and of these 57 (42.5%) relapsed. Progression to renal replacement therapy was seen in 10.1% (much lower than classically reported) with mortality in 29.8%. Amongst the whole cohort, those who went into remission had improved outcomes compared to those who did not go into remission (less progression to renal replacement therapy [4.5% vs 28%] and death [20.1% vs 67%]. Those classified as high-risk (based on parameters including eGFR, proteinuria, serum albumin, PLA2R antibody level, rate of renal function decline) also had worse outcomes than those at low-risk (mortality seen in 52.6% vs 10.8%, p<0.001). The median follow-up period was 59.5 months.

CONCLUSION

We provide a comprehensive epidemiologic analysis of primary membranous nephropathy at a large tertiary UK centre. Only 10.1% progressed to renal replacement therapy. For novelty, the KDIGO risk classification was linked to outcomes, highlighting the utility of this classification system for identifying patients most likely to progress.

Increasing Uptake of COVID-19 Vaccination and Reducing Health Inequalities in Patients on Renal Replacement Therapy-Experience from a Single Tertiary Centre

BACKGROUND

COVID-19 vaccination has changed the landscape of the COVID-19 pandemic; however, decreased uptake due to vaccine hesitancy has been observed, particularly in patients from minority ethnic backgrounds and socially deprived areas. These patient characteristics are common in patients on Renal Replacement Therapy (RRT), a population at extremely high risk of developing serious illness from COVID-19 and who would thus benefit the most from the vaccination programme. We designed a bespoke COVID-19 vaccination programme for our RRT population with the aim of decreasing health inequalities and increasing vaccination uptake.

METHODS

Key interventions included addressing vaccine hesitancy by deploying the respective clinical teams as trusted messengers, prompt eligible patient identification and notification, the deployment of resources to optimise vaccine administration in a manner convenient to patients, and the timely collection and analysis of local safety and efficacy data. First, COVID-19 vaccination data in relation to ethnicity and social deprivation in our RRT population, measured by the multiple deprivation index, were analysed and compared to uptake data in the total regional adult clinically extremely vulnerable (CEV) population in Greater Manchester (GM). Univariate logistic regression analysis was used to explore the factors associated with not receiving a vaccine.

RESULTS

Out of 1156 RRT patients included in this analysis, 96.7% received the first dose of the vaccination compared to 93% in the cohort of CEV patients in the GM. Age, gender, ethnicity, and a lower index of multiple deprivation were not identified as significant risk factors for poor first dose vaccine uptake in our cohort. Vaccine uptake in Asian and Black RRT patients was 94.9% and 92.3%, respectively, compared to 93% and 76.2% for the same ethnic groups in the reference CEV GM. Vaccine uptake was 96.1% for RRT patients in the lowest quartile of the multiple deprivation index, compared to 90.5% in the GM reference population.

CONCLUSION

Bespoke COVID-19 vaccination programmes based on local clinical teams as trusted messengers can improve negative attitudes towards vaccination and reduce health inequalities.

MO699: Investigating Longer Term Antibody Response Following Covid-19 Vaccination in Patients Receiving Peritoneal Dialysis—a Single-Center Observational Study

BACKGROUND AND AIMS

Individuals with end-stage kidney disease (ESKD) have a greater susceptibility towards coronavirus disease 2019 (COVID-19) infection compared to those without chronic kidney disease or ESKD, and these patients are more vulnerable to poor clinical outcomes. The introduction of COVID-19 vaccination programs displayed efficacy to improving clinical outcomes. A study based in the UK reported excellent humoral responses to the Pfizer BNT162b2 vaccine, but suboptimal responses to the Oxford AstraZeneca ChAdOx1-nCoV-19(AZD1222) vaccine amongst hemodialysis patients. High rate of humoral responses to two doses of the COVID-19 vaccination has been reported within small cohorts of peritoneal dialysis (PD) patients 3 to 8 weeks post vaccination, whilst one study confirmed maintenance of significant humoral responses 6 months post vaccination with the Pfizer BNT162b2 vaccine. Our study aimed at evaluating longer-term antibody responses—6 months after a two-dose regimen of the Pfizer BNT162b2 and Oxford AstraZeneca ChAdOx1-nCoV-19 (AZD1222) vaccines in patients receiving PD.

METHOD

This is a single-center observational study conducted for PD patients who were offered both doses of the COVID-19 vaccine [either Pfizer BNT162b2 or Oxford AstraZeneca ChAdOx1-nCoV-19(AZD1222)] since universal introduction of the vaccination program in our local area in December 2020. COVID-19 antibody testing was performed using the Siemens’ immunoassay targeting the spike protein S1 RBD (an index ≥ 1.0 was deemed as a positive result) between October and November 2021. Demographic and baseline clinical data were collected for each patient, and analysis focused on comparing the characteristics between PD patients with positive and negative COVID-19 antibody statuses. Statistical analysis was performed using SPSS version 24.

RESULTS

Eighty-six patients were included in this study. The median age was 62 years (47–71) with a predominance of males (61.6%) and Caucasian ethnicity (75.6%). The majority of patients have hypertension (84.8%) with 38% having a history of cardiovascular disease and 34% being diabetic. Ten patients (11.6%) previously received a kidney transplant with 7 patients (8.2%) currently on immunosuppressive treatment, and 15 patients (17.4%) previously receiving such treatments. A total of 81 patients received both doses of the COVID-19 vaccine, of which 57 (70.4%) received Pfizer BNT162b2, 16 (19.7%) received Oxford AstraZeneca ChAdOx1-nCoV-19 (AZD1222) and the type of vaccine was unknown in 8 patients (9.9%). A total of 72 patients were COVID-19 antibody tested between October and November 2021 in which 68 (94.4%) had a positive antibody and 4 (5.6%) had a negative antibody test. The median time between first dose of the COVID-19 vaccination and antibody testing was 9 (8.6–9.5) months and the median time between second dose of the COVID-19 vaccination and antibody testing was 6.3 (5.8–6.7) months. Comparing the demographic and clinical characteristics between patients with positive and negative antibodies, a higher proportion of patients with history of receiving immunosuppression (currently or previously; P = 0.004) had a negative antibody status despite receiving two doses of COVID-19 vaccination. There were no further significant differences observed. Full study results are presented in Tables 1 and 2.

CONCLUSION

In our cohort of PD patients, detectable humoral response to COVID-19 vaccination was sustained 6 months following vaccination irrespective of the type of vaccination received. A higher proportion of patients with a history of receiving immunosuppression (current or past) had a poor antibody response following COVID-19 vaccinations, highlighting the importance of considering focused COVID-19 vaccination strategies in the context of immunosuppression.

Evaluating the antibody response to SARS-COV-2 vaccination amongst kidney transplant recipients at a single nephrology centre

Background and objectives

Kidney transplant recipients are highly vulnerable to the serious complications of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infections and thus stand to benefit from vaccination. Therefore, it is necessary to establish the effectiveness of available vaccines as this group of patients was not represented in the randomized trials.

Design, setting, participants, & measurements

A total of 707 consecutive adult kidney transplant recipients in a single center in the United Kingdom were evaluated. 373 were confirmed to have received two doses of either the BNT162b2 (Pfizer-BioNTech) or AZD1222 (Oxford-AstraZeneca) and subsequently had SARS-COV-2 antibody testing were included in the final analysis. Participants were excluded from the analysis if they had a previous history of SARS-COV-2 infection or were seropositive for SARS-COV-2 antibody pre-vaccination. Multivariate and propensity score analyses were performed to identify the predictors of antibody response to SARS-COV-2 vaccines. The primary outcome was seroconversion rates following two vaccine doses.

Results

Antibody responders were 56.8% (212/373) and non-responders 43.2% (161/373). Antibody response was associated with greater estimated glomerular filtration (eGFR) rate [odds ratio (OR), for every 10 ml/min/1.73m² = 1.40 (1.19–1.66), P<0.001] whereas, non-response was associated with mycophenolic acid immunosuppression [OR, 0.02(0.01–0.11), p<0.001] and increasing age [OR per 10year increase, 0.61(0.48–0.78), p<0.001]. In the propensity-score analysis of four treatment variables (vaccine type, mycophenolic acid, corticosteroid, and triple immunosuppression), only mycophenolic acid was significantly associated with vaccine response [adjusted OR by PSA 0.17 (0.07–0.41): p<0.001]. 22 SARS-COV-2 infections were recorded in our cohort following vaccination. 17(77%) infections, with 3 deaths, occurred in the non-responder group. No death occurred in the responder group.

Conclusion

Vaccine response in allograft recipients after two doses of SARS-COV-2 vaccine is poor compared to the general population. Maintenance with mycophenolic acid appears to have the strongest negative impact on vaccine response.

A Quality Improvement Project to Minimize COVID-19 Infections in Patients Receiving Haemodialysis and the Role of Routine Surveillance Using Nose and Throat Swabs for SARS-CoV-2 rRT-PCR and Serum Antibody Testing

Background

Patients receiving in-centre haemodialysis (ICHD) are highly vulnerable to COVID-19.

Objective

We created a quality improvement (QI) project aimed to eliminate outbreaks of COVID-19 in haemodialysis units and evaluated the utility of surveillance rRT-PCR test and SARS-CoV-2 serum antibodies for prompt identification of patients infected with COVID-19.

Methods

A multifaceted QI programme including a bundle of infection prevention control (IPC) measures was implemented across 5 ICHD units following the first wave of the pandemic in June 2020. Primary outcomes evaluated before and after QI implementation were incidence of outbreaks and severe COVID-19 illness defined as COVID-19-related death or hospitalization. Secondary outcomes included the proportion of patients identified in the pre-symptomatic/asymptomatic phase on surveillance rRT-PCR screening and the incidence and longevity of SARS-CoV-2 antibody response.

Results

Following the implementation of the QI project, there were no further outbreaks. Pre- and post-implementation comparison showed a significant reduction in COVID-19-related mortality and hospitalization (26 vs. 13 events, respectively, p < 0.001). Surveillance rRT-PCR screening identified 39 asymptomatic or pre-symptomatic cases out of a total of 59 rRT-PCR-positive patients (39/59, 66%). SARS-CoV-2 antibody levels were detected in 72/74 (97%) rRT-PCR-positive patients. Amongst rRT-PCR-positive patients diagnosed before August 2020, 96% had detectable antibodies until January 2021 (days from the rRT-PCR test to last antibody testing, 245–280).

Conclusions

Systematic implementation of a bundle of IPC measures using QI methodology and surveillance rRT-PCR eliminated outbreaks in HD facilities. Most HD patients mount and sustain antibody response to COVID-19 for over 8 months.

Occupational exposure of healthcare workers to COVID-19 and infection prevention control measures in haemodialysis facilities in North West of England

COVID-19 infection rates in haemodialysis (HD) facilities are extremely high and are attributed to the high burden of comorbidities of HD patients coupled with inability to self-isolate needing thrice weekly attendance for HD treatment. Healthcare workers (HCW) in HD facilities are at risk of occupational exposure to COVID-19. Infection prevention control (IPC) measures were introduced during the pandemic aiming at reducing transmission and occupational exposure risk of COVID-19. Here we describe the results of our baseline and follow up occupational exposure audit in a renal centre in the North West of England following the implementation of a multifaceted IPC bundle.

A pilot project evaluating a fixed drainage system (U-Drain) for automated peritoneal dialysis

U-Drain is a fixed drainage system for automated peritoneal dialysis (APD) connecting the dialysis effluent outflow directly to the household drainage system thus avoiding the need for drain bags, with considerable potential advantages for patient convenience and reduction of plastic clinical waste. Here we present a pilot project reporting on U-Drain patient and staff experience based on questionnaires and on the safety of the technology derived from analysis of characteristics of peritonitis episodes. Overall, 15 patients were included in the pilot project and were followed up over 3 years; 11 patients completed a questionnaire exploring their experiences of APD and U-Drain. A family member 55%, carer 10%, healthcare assistant 10% and patient themselves 25% would normally carry the full drainage bags for disposal. Following the installation of U-Drain, 90% of patients reported that the system saved them time setting up and clearing the machine after dialysis, 80% noted a reduction in storage space required for consumables and all patients noted a reduction in non-recyclable waste requiring disposal. All patients who completed the questionnaire were very satisfied with the installation. All staff members who completed the questionnaire reported that their role was easier and the system was time saving. In total, there were 8 peritonitis episodes, including 2 recurrent infections due to biofilm, over 313 patient months follow up. There was no increase in incidence of peritonitis infection (0.3 episodes per year at risk) compared to that in the unit's population (0.64, 0.42 and 0.5 episodes per year at risk for the years 2017, 2018 and 2019, respectively) or delays in diagnosis. Approximately 0.8 kg of non-recyclable clinical waste was saved per treatment day from domestic waste by avoiding the use of PD drain bags. This pilot demonstrates increased patient satisfaction and acceptable safety profile of U-Drain technology.

Investigating the utility of COVID-19 antibody testing in end-stage renal disease patients receiving haemodialysis: a cohort study in the United Kingdom

Background

End-stage renal disease (ESRD) patients receiving haemodialysis (HD) are a vulnerable group of patients with increased mortality from COVID-19. Despite improved understanding, the duration of host immunity following COVID-19 infection and role of serological testing alone or in addition to real-time reverse transcription polymerase chain reaction (rRT-PCR) testing in the HD population is not fully understood, which this study aimed to investigate.

Methods

There were two parts to this study. Between 15th March 2020 to 15th July 2020, patients receiving HD who tested positive on rRT-PCR for SARS-CoV-2 were recruited into the COVID-19 arm, whilst asymptomatic patients without a previous diagnosis of COVID-19 were recruited to the epidemiological arm of the Salford Kidney Study (SKS). All patients underwent monthly testing for anti-SARS-CoV-2 antibodies as per routine clinical practice since August 2020. The aims were twofold: firstly, to determine seroprevalence and COVID-19 exposure in the epidemiological arm; secondly, to assess duration of the antibody response in the COVID-19 arm. Baseline characteristics were reviewed between groups. Statistical analysis was performed using SPSS. Mann-Whitney U and Chi-squared tests were used for testing significance of difference between groups.

Results

In our total HD population of 411 patients, 32 were PCR-positive for COVID-19. Of the remaining patients, 237 were recruited into the SKS study, of whom 12 (5.1%) had detectable anti-SARS-CoV-2 antibodies. Of the 32 PCR-positive patients, 27 (84.4%) were symptomatic and 25 patients admitted to hospital due to their symptoms. Of the 22 patients in COVID-19 arm that underwent testing for anti-SARS-CoV-2 IgG antibodies beyond 7 months, all had detectable antibodies.

A higher proportion of the patients with COVID-19 were frail compared to patients without a diagnosis of COVID-19 (64.3% vs 34.1%, p = 0.003). Other characteristics were similar between the groups. Over a median follow up of 7 months, a higher number of deaths were recorded in patients with a diagnosis of COVID-19 compared to those without (18.7% vs 5.9%, p = 0.003).

Conclusions

Serological testing in the HD population is a valuable tool to determine seroprevalence, monitor exposure, and guide improvements for infection prevention and control (IPC) measures to help prevent local outbreaks. This study revealed HD patients mount a humoral response detectable until at least 7 months after COVID-19 infection and provides hope of similar protection with the vaccines recently approved.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02366-2.

Safely reducing haemodialysis frequency during the COVID-19 pandemic

BACKGROUND

Patients undergoing haemodialysis (HD) are at higher risk of developing worse outcomes if they contract COVID-19. In our renal service we reduced HD frequency from thrice to twice-weekly in selected patients with the primary aim of reducing COVID 19 exposure and transmission between HD patients.

METHODS

Dialysis unit nephrologists identified 166 suitable patients (38.4% of our HD population) to temporarily convert to twice-weekly haemodialysis immediately prior to the peak of the COVID-19 pandemic in our area. Changes in pre-dialysis weight, systolic blood pressure (SBP) and biochemistry were recorded weekly throughout the 4-week project. Hyperkalaemic patients (serum potassium > 6.0 mmol/L) were treated with a potassium binder, sodium bicarbonate and received responsive dietary advice.

RESULTS

There were 12 deaths (5 due to COVID-19) in the HD population, 6 of which were in the twice weekly HD group; no deaths were definitively associated with change of dialysis protocol. A further 19 patients were either hospitalised and/or developed COVID-19 and thus transferred back to thrice weekly dialysis as per protocol. 113 (68.1%) were still receiving twice-weekly HD by the end of the 4-week project. Indications for transfer back to thrice weekly were; fluid overload (19), persistent hyperkalaemia (4), patient request (4) and compliance (1). There were statistically significant increases in SBP and pre-dialysis potassium during the project.

CONCLUSIONS

Short term conversion of a large but selected HD population to twice-weekly dialysis sessions was possible and safe. This approach could help mitigate COVID-19 transmission amongst dialysis patients in centres with similar organisational pressures.

P0619POINT OF CARE CREATININE FOR EARLY DIAGNOSIS OF COMMUNITY ACQUIRED ACUTE KIDNEY INJURY IN NIGERIA. TECHNOLOGY EVALUATION AND DESIGN OF QUALITY IMPROVEMENT PROJECT

Background and Aims

Acute Kidney Injury (AKI) in low- and middle-income countries is mostly a community-acquired potentially reversible syndrome and has high morbidity and mortality. Due to limited laboratory infrastructure diagnosis of AKI is often delayed until life threatening complications have developed and dialysis treatment is largely unavailable. Decisions for hospital referral from primary health care centers and triage decisions for hospital admission are not based on laboratory results in Port Harcourt Nigeria. To address the need for early diagnosis and treatment of AKI we established a collaboration between the Renal Unit of the University of Port Harcourt Teaching Hospital, Primary Health Care Board Rivers State and the Renal Department of Salford Royal NHS Foundation Trust, aiming at the evaluation of the use of point of care (POC) Creatinine (Cr) for early detection and management of community acquired AKI.

Method

The first stage of the project evaluated the accuracy of POC Cr technology. Following informed consent patients underwent concurrent measurement of Cr using the central laboratory (Lab) assay (Jaffe) from a venous sample and a point of care Cr measurement using a capillary sample (fingerstick) with the NOVA Stasensor Xpress Cr analyser. Pearson Correlation and Bland-Altman plots were used to assess correlation and agreement between the two methods. During the second stage, the results were discussed at a focused AKI workshop and guidance for the use of POC Cr was developed.

Results

During the first phase 96 concurrent POC Cr capillary and venous Lab Cr samples were analysed. Mean age was 49±14 years and 66 subjects were females. POC Cr values were 127±122 umol/l and Lab Cr values were 100 ±85 umol/L, mean positive bias of 27.2±47.94 umol/L. Overall, correlation between POC Cr and Lab Cr was very good, with Pearson correlation r=0.956) Figure 1A. All 4 out of 96 values that were outside the limits of agreement (set at mean ±2 standard deviations) were for Lab Cr values &gt;200 umol/L. A Bland-Altman Plot is presented for paired samples with Lab Cr values &lt;200 umol/L (Figure 1B).

Bitumen surface microstructure evolution in subzero environments

Bitumen is a widely used material employed as a binder in pavement engineering and as a surface sealant in construction. Its surface microstructure and microscale properties have been shown to be temperature-dependent, with effects manifesting themselves on surface composition and texture, including the formation of the visually striking catana 'bee'-like structures. Despite the importance of a good performance of bitumen in subzero environments (<0°C), the behaviour of bitumen surface texture and composition at cold temperatures, affecting cracking, degradation and road icing, has received practically no attention. In particular, such knowledge is relevant to world regions experiencing long periods of subzero temperatures during the year. Employing advanced atomic force microscopy combined with infrared spectroscopy (AFM-IR) and an environmental chamber, we demonstrate the ability to characterise surface structure and composition with nanoscale precision for a broad range of temperatures. We show that cooling bitumen to subzero temperatures can have several interesting effects on its surface microtexture, nanotexture and composition, especially on its three surface domains, catana, peri and para. We found that the para domain coarsens and extends to form an interfacial transition domain (characterised by increasing surface roughness with peri domain composition) between the para and peri domains. We show that the catana and peri domains have a similar composition, but have different mechanical and chemical properties compared to the para domain. The essential findings of this work improve our understanding of the behaviour of bitumen in subzero environments, aiding us in our quest towards attaining better road and sealant performance.

The potential of electrocardiography for cardiac risk prediction in chronic and end-stage kidney disease

Cardiovascular mortality is very high in chronic and end-stage kidney disease (ESKD). However, risk stratification data are lacking. Sudden cardiac deaths are among the most common cardiovascular causes of death in these populations. As a result, many studies have assessed the prognostic potential of various electrocardiographic parameters in the renal population. Recent data from studies of implantable loop recordings in haemodialysis patients from five different countries have shed light on a pre-eminent bradyarrhythmic risk of mortality. Importantly, heart block addressed by permanent pacing system was detected in a proportion of patients during the prolonged recording periods. Standard electrocardiogram is inexpensive, non-invasive and easily accessible. Hence, risk prediction models using this simple investigation tool could easily translate into clinical practice. We believe that electrocardiographic assessment is currently under-valued in renal populations. For this review, we identified studies from the preceding 10 years that assessed the use of conventional and novel electrocardiographic biomarkers as risk predictors in chronic and ESKD. The review indicates that conventional electrocardiographic markers are not reliable for risk stratification in the renal populations. Novel parameters have shown promising results in smaller studies, but further validation in larger populations is required.

The importance of acute kidney injury in suspected community acquired infection

Background

Most sepsis and acute kidney injury (AKI) cases are community acquired (CA). The aim of this study was to evaluate the characteristics of suspected community acquired infection (sCA-I) and CA-AKI and their impact upon patient outcomes.

Methods

All adult creatinine blood tests from non-elective, non-dialysis attendances to a single centre over a 29-month period were analysed retrospectively. We defined sCA-I and CA-AKI cases as antibiotic prescription and AKI alert within 48 hours of attendance respectively. Binary logistic regression models were created to determine associations with 30-day mortality, intensive care unit (ICU) admission and length of stay (LOS) dichotomised at median.

Results

Of 61,471 attendances 28.1% and 5.7% suffered sCA-I or CA-AKI in isolation respectively, 3.4% suffered both. sCA-I was present in 58.8% of CA-AKI cases and CA-AKI was present in 11.9% of CA-I cases. The combination of sCA-I and CA-AKI was associated with a higher risk for all outcomes compared to sCA-I or CA-AKI in isolation. The 30-day mortality was 8.1%, 11.8% and 26.2% in patients with sCA-I, CA-AKI and when sCA-I and CA-AKI occurred in combination respectively. The adjusted odds ratios (OR) and 95% confidence intervals (CI) for 30-day mortality, ICU admission and LOS for sCA-I combined with CA-AKI stage 1 were OR 6.09:CI: 5.21–7.12, OR 12.52 CI: 10.54–14.88 and OR 8.97 CI: 7.62–10.56, respectively, and for combined sCA-I and CA-AKI stage 3 were OR 9.23 CI: 6.91–12.33, OR 29.26 CI: 22.46–38.18 and OR 9.48 CI: 6.82–13.18 respectively.

Conclusion

The combination of sCA-I and CA-AKI is associated with worse outcomes.

The effect of level of injury and physical activity on heart rate variability following spinal cord injury

OBJECTIVE/BACKGROUND

To assess frequency domain heart rate variability (HRV) parameters at rest and in response to postural autonomic provocations in individuals with spinal cord injury (SCI) and investigate the autonomic influences on the heart of different physical activities.

DESIGN

Cross-sectional study.

METHODS

Ten subjects with complete cervical SCI and fourteen subjects with complete low thoracic SCI were prospectively recruited from the community and further divided in sedentary and physically active groups, the latter defined as regular weekly 4 hour physical activity for the preceding 3 months. Sixteen healthy individuals matched for sex and age were recruited to participate in the control group. The Low Frequency (LF), High Frequency (HF) powers and the LF/HF ratio of HRV were measured from continuous electrocardiogram (ECG) recordings at rest and after sitting using a fast Fourier transformation.

OUTCOME MEASURES

The LF,HF, and the LF/HF ratio at rest and after sitting.

RESULTS

A significant decrease in all HRV parameters in patients with SCI was found compared to controls. The change in HF, LF and LF/HF following sitting maneuver was significantly greater in controls as compared with the SCI group and greater in subjects with paraplegia as compared to subjects with tetraplegia. Better HRV values and enhanced vagal activity appears to be related to the type of physical activity in active subjects with paraplegia.

CONCLUSION

In this cohort of subjects spectral parameters of HRV were associated with the level of the injury. Passive standing was associated with higher HRV values in subjects with paraplegia.

Sudden Cardiac Death in Dialysis: Arrhythmic Mechanisms and the Value of Non-invasive Electrophysiology

Sudden Cardiac Death (SCD) is the leading cause of cardiovascular death in dialysis patients. This review discusses potential underlying arrhythmic mechanisms of SCD in the dialysis population. It examines recent evidence from studies using implantable loop recorders and from electrophysiological studies in experimental animal models of chronic kidney disease. The review summarizes advances in the field of non-invasive electrophysiology for risk prediction in dialysis patients focusing on the predictive value of the QRS-T angle and of the assessments of autonomic imbalance by means of heart rate variability analysis. Future research directions in non-invasive electrophysiology are identified to advance the understanding of the arrhythmic mechanisms. A suggestion is made of incorporation of non-invasive electrophysiology procedures into clinical practice. Key Concepts: - Large prospective studies in dialysis patients with continuous ECG monitoring are required to clarify the underlying arrhythmic mechanisms of SCD in dialysis patients. - Obstructive sleep apnoea may be associated with brady-arrhythmias in dialysis patients. Studies are needed to elucidate the burden and impact of sleeping disorders on arrhythmic complications in dialysis patients. - The QRS-T angle has the potential to be used as a descriptor of uremic cardiomyopathy. - The QRS-T angle can be calculated from routine collected surface ECGs. Multicenter collaboration is required to establish best methodological approach and normal values. - Heart Rate Variability provides indirect assessment of cardiac modulation that may be relevant for cardiac risk prediction in dialysis patients. Short-term recordings with autonomic provocations are likely to overcome the limitations of out of hospital 24-h recordings and should be prospectively assessed.

QRS-T Angle Predicts Cardiac Risk and Correlates With Global Longitudinal Strain in Prevalent Hemodialysis Patients

Background: Cardiovascular disease is the commonest cause of death in hemodialysis (HD) patients but accurate risk prediction is lacking. The spatial QRS – T angle is a promising electrophysiological marker for sudden cardiac death risk stratification. The aim of this study was to assess the prognostic value of spatial QRS-T angle derived from standard 12 lead electrocardiograms (ECG) and its association with echocardiographic parameters in HD patients.

Methods: This prospective study of 178 prevalent HD patients (aged 67 ± 14 years, 72% men) collected ECG and echocardiographic data on an annual basis. Baseline echocardiograms at study entry were used for cross-sectional comparisons with ECGs. Study endpoints were all-cause mortality, cardiovascular mortality, and major adverse cardiac events (MACE). The QRS – T angle was calculated from standard 10-s ECG as the total cosine R to T (TCRT) using singular value decomposition and expressed in degrees. TCRT above 100° was defined as abnormal.

Results: During a follow-up period of 36 ± 19 months, 74 patients died, including 17 cardiac deaths, and 54 suffered from MACE. In multivariate Cox regression analysis, QRS-T angle by TCRT at baseline was associated with increased cardiovascular mortality both as a continuous value and dichotomized below or above 100° (HR 1.016, p = 0.029, CI: 1.002–1.030 and HR 3.506, CI: 1.118–10.995, p = 0.031 respectively) and with MACE dichotomized at 100° (HR 1.902, CI: 1.046–3.459; p = 0.035). In multivariate regression analysis including baseline parameters, echocardiographic global longitudinal strain (GLS) was significantly correlated with TCRT (F 9.648, r² = 0.192, standardized β = 0.331, unstandardized β = 3.567, t = 4.4429, CI: 1.976–5.157, p < 0.001).

Conclusion: TCRT correlates with GLS and is independently associated with cardiac deaths and MACE in HD patients.

Improved management of acute kidney injury in primary care using e-alerts and an educational outreach programme

PURPOSE

Acute kidney injury (AKI) detected in primary care is associated with increased morbidity and mortality. AKI electronic alerts (e-alerts) and educational programmes have recently been implemented but their contribution to improve AKI care is unknown. This project aimed to improve response to AKI detected in primary care and used a factorial design to evaluate the impact of the UK National Health Service (NHS) AKI e-alert and AKI educational outreach sessions on time to response to primary care AKI stages 2 and 3 between April and August 2016.

METHODS

A total of 46 primary care practices were randomized into four groups. A 2 × 2 factorial design exposed each group to different combinations of two interventions. The primary outcome was 'time to repeat test' or hospitalization following AKI e-alert for stages 2 and 3. Yates algorithm was used to evaluate the impact of each intervention. Time to response and mortality pre- and post-intervention were analysed using Mann-Whitney U test and chi-square test respectively. The factorial design included two interventions: an AKI educational outreach programme and the NHS AKI e-alerts.

RESULTS

1807 (0.8%) primary care blood tests demonstrated AKI 1-3 (78.3% stage 1, 14.8% stage 2, 6.9% stage 3). There were 391 stage 2 and 3 events from 251 patients. E-alerts demonstrated a reduction in mean response time (-29 hours). Educational outreach had a smaller effect (-3 hours). Median response time to AKI 2 and 3 pre- and post-interventions was 27 hours versus 16 hours respectively (P = 0.037). Stage 2 and 3 event-related 30-day all-cause mortality decreased following the interventions (15.6% versus 3.9% P = 0.036).

CONCLUSION

AKI e-alerts in primary care hasten response to AKI 2 and 3 and reduce all-cause mortality. Educational outreach sessions further improve response time.

Reducing acute kidney injury incidence and progression in a large teaching hospital

Acute kidney injury (AKI) is a common syndrome that is associated with significant mortality and cost. The Quality Improvement AKI Collaborative at Salford Royal Foundation Trust was established to review and improve both the recognition and management of AKI. This was a whole-system intervention to tackle AKI implemented as an alternative to employing separate AKI nurses. Our aims were to reduce the overall incidence of AKI by 10%, to reduce hospital-acquired AKI by 25% and to reduce the progression of AKI from stage 1 to stage 2 or 3 by 50%. From 2014 to 2016, several multifaceted changes were introduced. These included system changes, such as inserting an e-alert for AKI into the electronic patient record, an online educational package and face-to-face teaching for AKI, and AKI addition to daily safety huddles. On 10 Collaborative wards, development of an AKI care bundle via multidisciplinary team (MDT) plan, do, study, act testing occurred. Results showed a 15.6% reduction in hospital-wide-acquired AKI, with a 22.3% reduction on the collaborative wards. Trust-wide rates of progression of AKI 1 to AKI 2 or 3 showed normal variation, whereas there was a 48.5% reduction in AKI progression on the Collaborative wards. This implies that e-alerts were ineffective in isolation. The Collaborative wards' results were a product of the educational support, bundle and heightened awareness of AKI. A number of acute hospitals have demonstrated impactful successes in AKI reduction centred on a dedicated AKI nurse model plus e-alerting with supporting changes. This project adds value by highlighting another approach that does not require a new post with attendant rolling costs and risks. We believe that our approach increased our efficacy in acute care in our front-line teams by concentrating on embedding improved recognition and actions across the MDT.

Arrhythmia in hemodialysis patients and its relation to sudden death

Sudden death in patients on hemodialysis is believed to be due to arrhythmia, but the evidence for this is surprisingly limited. Five studies involving implantable loop recorders in patients on hemodialysis have now been published, and 4 have shown that bradyarrhythmia rather than tachyarrhythmia are the pre-eminent arrhythmic associations of fatal events. The Monitoring in Dialysis study, reported in this issue, sheds new light on the relationships of arrhythmia to the conventional 3-session weekly hemodialysis cycle.

Association of QRS-T angle and heart rate variability with major cardiac events and mortality in hemodialysis patients

INTRODUCTION

Mortality in hemodialysis (HD) patients is high with significant proportion attributed to fatal arrhythmias. In a pilot study, we showed that intradialytic electrocardiographic (ECG) monitoring can yield stable profiles of selected repolarisation descriptors and heart rate variability (HRV) parameters. This study investigated the relationship of these ECG markers with major adverse cardiac events (MACE) and mortality.

METHODS

Continuous ECGs were obtained during HD and repeated five times at 2-week intervals. The QRS-T angle calculated as Total Cosine R to T (TCRT) and T-wave morphology dispersion (TMD) were calculated in overlapping 10 s ECG segments. High- (HF) and low (LF)-frequency components and the LF/HF ratio of HRV were calculated every 5 min. These indices were averaged during the first hour of dialysis and subsequently overall recordings in each subject.

RESULTS

All ECG parameters were available in 72 patients aged 61 ± 15, 23 (31.9%) females and 26 (36.1%) diabetics. After a median follow up of 54.8 months, 16 patients died, 20 were transplanted, and 9 suffered MACE. TCRT (in degrees) was higher and LF/HF was lower in patients who died compared to survivors (112 ± 30 vs. 73 ± 35, p = 0.000 and 0.222 ± 0.418 vs. 0.401 ± 0.274, p = 0.000, respectively) and in MACE positive compared to negative (117 ± 40 vs. 77 ± 34, p = 0.017 and 0.125 ± 0.333 vs.0.401 ± 0.274, p = 0.007 respectively). In multivariate Cox regression analysis of mortality risk adjusted for age, diabetes mellitus, and coronary artery disease, TCRT and LF/HF remained significant predictors (p < 0.05).

CONCLUSION

QRS-T angle and HRV may serve risk assessment in future prospective studies in HD patients.

The Evidence of Acute Kidney Injury in the Community and for Primary Care Interventions

BACKGROUND

Almost two-thirds of patients with acute kidney injury (AKI) damage their kidneys whilst in the community. This paper aims to review existing data on incidence, mortality, and morbidity of AKI within the community and explore the evidence base for primary care strategies aimed at reducing incidence and improving early detection and management of AKI.

METHODS

A literature search was carried out using PubMed; key words including AKI, primary care, community acquired, and electronic alerts (e-alerts) were used to capture relevant data.

RESULTS

Incidence of AKI developing in the community is variable between studies due to differences in AKI definition. Community-acquired AKI (CA-AKI) but identified in hospital (CAH-AKI) is more prevalent than hospital-acquired AKI and increases short- and long-term mortality and length of stay in hospital. CA-AKI identified in primary care is less severe than CAH-AKI but is associated with increased mortality. The use of e-alerts has good diagnostic accuracy for detecting AKI but their impact on outcomes in secondary care remains uncertain; it is likely that they should be complemented with other interventions to improve management. Evidence has not yet emerged regarding the effects of e-alerts on outcomes in primary care.

CONCLUSION

Given the significance of developing AKI in the community, strategies to aid early detection and promote prevention are warranted. A multifaceted approach combining e-alerts, educational programs, and care bundles across the interface between primary and secondary care has the potential to improve outcomes in the future.

CMV disease complicating induction immunosuppressive treatment for ANCA-associated vasculitis

We present a case of a 71-year-old woman who initially presented with renal-limited antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. Following standard therapy with cyclophosphamide, steroids and plasma exchange, her renal function began to improve. However, despite appropriate treatment, her renal function subsequently deteriorated and she suffered haemoptysis. Owing to diagnostic uncertainty, bronchoscopy and a repeat renal biopsy were performed. The bronchoscopy washings demonstrated positivity for cytomegalovirus (CMV) DNA, and in combination with a positive serum CMV PCR, immunosuppression was withheld. Treatment with ganciclovir was started. Repeat renal biopsy demonstrated active vasculitis and, following successful treatment of CMV disease, immunosuppression was re-started alongside prophylactic valganciclovir. This resulted in a successful outcome for the patient. Pulmonary CMV disease may mimic pulmonary disease associated with vasculitis, posing a diagnostic challenge to clinicians. We recommend a low threshold when testing for CMV in these patients.

Sub-micron lateral topography affects endothelial migration by modulation of focal adhesion dynamics

Through the interaction with topographical features, endothelial cells tune their ability to populate target substrates, both in vivo and in vitro. Basal textures interfere with the establishment and maturation of focal adhesions (FAs) thus inducing specific cell-polarization patterns and regulating a plethora of cell activities that govern the overall endothelial function. In this study, we analyze the effect of topographical features on FAs in primary human endothelial cells. Reported data demonstrate a functional link between FA dynamics and cell polarization and spreading on structured substrates presenting variable lateral feature size. Our results reveal that gratings with 2 µm lateral periodicity maximize contact guidance. The effect is linked to the dynamical state of FAs. We argue that these results are readily applicable to the rational design of active surfaces at the interface with the blood stream.