ABSTRACT
Peritoneal dialysis (PD) enables people to have a home-based therapy, permitting greater autonomy for individuals along with enhanced treatment satisfaction compared with in-center dialysis care. The burden of treatment on PD, however, remains considerable and underpins the need for person-centered care. This reflects the need to address the patient as a person with needs and preferences beyond just the medical perspective. Shared decision making is central to the recent International Society for Peritoneal Dialysis recommendations for prescribing PD, balancing the potential benefits of PD on patient well-being with the burden associated with treatment. This review considers the role of high-quality goal-directed prescribing, incremental dialysis, and remote patient monitoring in reducing the burden of dialysis, including an approach to implementing incremental PD. Although patient-related outcomes are important in assessing the response to treatment and, particularly life participation, the corollary of dialysis burden, there are no clear routes to the clinical implementation of patient-related outcome measures. Delivering person-centered care is dependent on treating people both as individuals and as equal partners in their care.
Subject(s)
Peritoneal Dialysis , Humans , Renal Dialysis , Outcome Assessment, Health Care , PatientsABSTRACT
Home dialysis therapies offer a significant benefit to patients in respect of quality of life and autonomy, as compared with in-centre haemodialysis. There is significant unwarranted variation across the world in the availability of both peritoneal dialysis (PD) and home haemodialysis, which has led in the UK to a recommendation of a minimum 20% prevalent rate of dialysis patients at home. Key advances in PD have included changes in the approach to prescribing PD and the use of assisted dialysis. Peritonitis remains a significant complication which may present to general physicians and needs prompt recognition and treatment. The development of novel small dialysis machines has led to a resurgence of interest in home haemodialysis.
Subject(s)
Kidney Failure, Chronic , Peritoneal Dialysis , Humans , Hemodialysis, Home/adverse effects , Hemodialysis, Home/methods , Renal Dialysis , Quality of Life , Kidney Failure, Chronic/therapy , Peritoneal Dialysis/adverse effects , Peritoneal Dialysis/methodsABSTRACT
We have developed a supportive two-exchange assisted continuous ambulatory peritoneal dialysis (asCAPD) programme for the older frail person who cannot do autonomous PD and do not want or are considered to be too high risk for haemodialysis (HD). Evaluation of the programme was determined by data collected retrospectively from patient records. Primary outcome was comparison of symptoms at start of dialysis and 3 months following dialysis start. Secondary outcomes were survival and peritonitis rate. Over a 4-year period (2016-2020), 49 patients with mean age 79.6 years (range 47-90) enrolled in the programme with eGFR 7.7 ± 2.6 ml/min (mean ± SD) at dialysis start. Forty-one patients had been on asCAPD for >3 months. There was an improvement in all symptoms at 3 months compared to baseline: anorexia (46% to 15%), fatigue (46% to 15%), shortness of breath (27% to 2%) and oedema (51% to 32%). One-year survival was 55%. Peritonitis rate was 0.52 episodes per patient year. The novel supportive two-exchange asCAPD programme shows potential improvement of symptoms after 3 months and may provide an acceptable dialysis modality for the frail co-morbid person with established kidney failure. More detailed study and evaluation are needed.
Subject(s)
Kidney Failure, Chronic , Peritoneal Dialysis, Continuous Ambulatory , Peritonitis , Aged , Aged, 80 and over , Humans , Middle Aged , Frail Elderly , Kidney Failure, Chronic/diagnosis , Kidney Failure, Chronic/therapy , Peritoneal Dialysis, Continuous Ambulatory/adverse effects , Peritonitis/epidemiology , Peritonitis/etiology , Retrospective StudiesABSTRACT
BACKGROUND AND OBJECTIVES: Patients receiving hemodialysis are at high risk from coronavirus disease 2019 (COVID-19) and demonstrate impaired immune responses to vaccines. There have been several descriptions of their immunologic responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, but few studies have described the clinical efficacy of vaccination in patients on hemodialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In a multicenter observational study of the London hemodialysis population undergoing surveillance PCR testing during the period of vaccine rollout with BNT162b2 and AZD1222, all of those positive for SARS-CoV-2 were identified. Clinical outcomes were analyzed according to predictor variables, including vaccination status, using a mixed effects logistic regression model. Risk of infection was analyzed in a subgroup of the base population using a Cox proportional hazards model with vaccination status as a time-varying covariate. RESULTS: SARS-CoV-2 infection was identified in 1323 patients of different ethnicities (Asian/other, 30%; Black, 38%; and White, 32%), including 1047 (79%) unvaccinated, 86 (7%) after first-dose vaccination, and 190 (14%) after second-dose vaccination. The majority of patients had a mild course; however, 515 (39%) were hospitalized, and 172 (13%) died. Older age, diabetes, and immune suppression were associated with greater illness severity. In regression models adjusted for age, comorbidity, and time period, prior two-dose vaccination was associated with a 75% (95% confidence interval, 56 to 86) lower risk of admission and 88% (95% confidence interval, 70 to 95) fewer deaths compared with unvaccinated patients. No loss of protection was seen in patients over 65 years or with increasing time since vaccination, and no difference was seen between vaccine types. CONCLUSIONS: These data demonstrate a substantially lower risk of severe COVID-19 after vaccination in patients on dialysis who become infected with SARS-CoV-2.
Subject(s)
BNT162 Vaccine , COVID-19 , ChAdOx1 nCoV-19 , Renal Dialysis , BNT162 Vaccine/administration & dosage , COVID-19/epidemiology , COVID-19/prevention & control , ChAdOx1 nCoV-19/administration & dosage , Humans , London , Prospective Studies , Severity of Illness Index , VaccinationABSTRACT
BACKGROUND: Hemodialysis patients are at high risk of Covid-19, though vaccination has significant efficacy in preventing and reducing the severity of infection. Little information is available on disease severity and vaccine efficacy since the dissemination of the Omicron variant. METHODS: In a multi-center study, during a period of the epidemic driven by the Omicron variant, all hemodialysis patients positive for SARS-CoV-2 were identified. Outcomes were analyzed according to predictor variables including vaccination status. Risk of infection was analyzed using a Cox proportional hazards model. RESULTS: SARS-CoV-2 infection was identified in 1126 patients including 200 (18%) unvaccinated, 56 (5%) post first dose, 433 (38%) post second dose, and 437 (39%) at least 7 days beyond their third dose. The majority of patients had a mild course but 160 (14%) were hospitalized and 28 (2%) died. In regression models adjusted for age and comorbidity, two-dose vaccination was associated with a 39% (95%CI: 2%-62%) reduction in admissions, but third doses provided additional protection, with a 51% (95%CI: 25%-69%) further reduction in admissions. Among 1265 patients at risk at the start of the observation period, SARS-CoV-2 infection was observed in 211 (17%). Two-dose vaccination was associated with a 41% (95%CI: 3%-64%) reduction in the incidence of infection, with no clear additional effect provided by third doses. CONCLUSIONS: These data demonstrate lower incidence of SARS-CoV-2 infection after vaccination in dialysis patients during an Omicron dominant period of the epidemic. Among those developing infection, severe illness was less common with prior vaccination, particularly after third vaccine doses.
Subject(s)
COVID-19 , COVID-19/epidemiology , COVID-19/prevention & control , Cohort Studies , Humans , Renal Dialysis/adverse effects , SARS-CoV-2 , VaccinationABSTRACT
INTRODUCTION: Pericardial effusions and uremic pericarditis have been described in patients with kidney disease since 1836 [1] when they were considered a pre-terminal sign [2]. Fortunately today this pathology is less frequently encountered [3]; however, this has resulted in highly variable management. AIMS: This report aims to describe the case of a 61-year-old female presenting with a large pericardial effusion prior to kidney transplantation, and how local activity was reviewed to guide management. MATERIALS AND METHODS: We performed a retrospective service evaluation project, where 44 cases of pericardial effusion encountered at a tertiary renal center over 8 years were reviewed. Clinical data, investigation results, and outcomes were collected to identify the common clinical categories encountered and the role pericardial intervention may have had in those cases. RESULTS: A total of 44 cases of pericardial effusion were encountered, grouped into the following clinical categories; procedural (8), classical (3), uremic (15), and other etiology (18). Pericardial intervention occurred in 50% of cases due to current or impending hemodynamic compromise. Aspiration was of limited diagnostic use, providing a clinically relevant culture result in only one of the cases reviewed. No deaths were observed in the classical group, and 1-year survival was 86%, 67% and 43% in the uremic, other, and procedural groups, respectively. CONCLUSION: Our findings suggest that in patients with advanced kidney disease requiring renal replacement therapy and pericardial effusions, aspiration should largely be reserved for cases with hemodynamic compromise only, as in this series aspiration did not significantly improve diagnosis or guide subsequent treatment.
Subject(s)
Pericardial Effusion , Pericarditis , Uremia , Female , Humans , Middle Aged , Pericardial Effusion/diagnosis , Pericardial Effusion/etiology , Pericardial Effusion/surgery , Pericarditis/complications , Renal Dialysis/adverse effects , Retrospective Studies , Uremia/complications , Uremia/diagnosis , Uremia/therapyABSTRACT
BACKGROUND: In Europe, the number of elderly end-stage kidney disease patients is increasing. Few of those patients receive peritoneal dialysis (PD), as many cannot perform PD autonomously. Assisted PD programmes are available in most European countries, but the percentage of patients receiving assisted PD varies considerably. Hence, we assessed which factors are associated with the availability of an assisted PD programme at a centre level and whether the availability of this programme is associated with proportion of home dialysis patients. METHODS: An online survey was sent to healthcare professionals of European nephrology units. After selecting one respondent per centre, the associations were explored by χ2 tests and (ordinal) logistic regression. RESULTS: In total, 609 respondents completed the survey. Subsequently, 288 respondents from individual centres were identified; 58% worked in a centre with an assisted PD programme. Factors associated with availability of an assisted PD programme were Western European and Scandinavian countries (OR: 5.73; 95% CI: 3.07-10.68), non-academic centres (OR: 2.01; 95% CI: 1.09-3.72) and centres with a dedicated team for education (OR: 2.87; 95% CI: 1.35-6.11). Most Eastern & Central European respondents reported that the proportion of incident and prevalent home dialysis patients was <10% (72% and 63%), while 27% of Scandinavian respondents reported a proportion of >30% for both incident and prevalent home dialysis patients. Availability of an assisted PD programme was associated with a higher incidence (cumulative OR: 1.91; 95% CI: 1.21-3.01) and prevalence (cumulative OR: 2.81; 95% CI: 1.76-4.47) of patients on home dialysis. CONCLUSIONS: Assisted PD was more commonly offered among non-academic centres with a dedicated team for education across Europe, especially among Western European and Scandinavian countries where higher incidence and prevalence of home dialysis patients was reported.
Subject(s)
Kidney Failure, Chronic , Nephrology , Peritoneal Dialysis , Aged , Europe , Hemodialysis, Home , Humans , Kidney Failure, Chronic/epidemiology , Kidney Failure, Chronic/therapyABSTRACT
INTRODUCTION: Peritoneal dialysis (PD) remains underutilised and unplanned start of dialysis further diminishes the likelihood of patients starting on PD, although outcomes are equal to haemodialysis (HD). METHODS: A survey was sent to members of EuroPD and regional societies presenting a case vignette of a 48-year-old woman not previously known to the nephrology department and who arrives at the emergency department with established end-stage kidney disease (unplanned start), asking which dialysis modality would most likely be chosen at their respective centre. We assessed associations between the modality choices for this case vignette and centre characteristics and PD-related practices. RESULTS: Of 575 respondents, 32.8%, 32.2% and 35.0% indicated they would start unplanned PD, unplanned HD or unplanned HD with intention to educate patient on PD later, respectively. Likelihood for unplanned start of PD was only associated with quality of structure of the pre-dialysis program. Structure of pre-dialysis education program, PD program in general, likelihood to provide education on PD to unplanned starters, good collaboration with the PD access team and taking initiatives to enhance home-based therapies increased the likelihood unplanned patients would end up on PD. CONCLUSIONS: Well-structured pre-dialysis education on PD as a modality, good connections to dedicated PD catheter placement teams and additional initiatives to enhance home-based therapies are key to grow PD programs. Centres motivated to grow their PD programs seem to find solutions to do so.
Subject(s)
Kidney Failure, Chronic , Peritoneal Dialysis , Female , Humans , Incidence , Kidney Failure, Chronic/diagnosis , Kidney Failure, Chronic/epidemiology , Kidney Failure, Chronic/therapy , Middle Aged , Renal Dialysis , Surveys and QuestionnairesABSTRACT
BACKGROUND: Patient burnout is a major cause of technique failure on peritoneal dialysis (PD). Reducing the PD prescription on an individual basis, dependent upon residual kidney function (RKF), may have a role in prolonging time on PD by reducing dialysis burden. This retrospective study aimed to determine the safety and impact of flexible PD prescribing on technique and patient survival. METHODS: All patients (186) from our centre starting PD from 1st January 2012 to 31st December 2016 were included. Data on dialysis prescription were collected for each patient from the time they had started PD, and dialysis adequacy measured regularly (3-6 monthly) using PD Adequest. RESULTS: Median age at start of dialysis was 61 years. Only 49% started on PD 7 days a week and this dropped to 27% at 3 months following the first clearance test. Over 90% achieved creatinine clearance > 50 L/week/1.73 m2 up to 2 years of follow-up, with 87% achieving this standard at 3 years. Patient and technique survival at 1, 2 and 3 years were 91%, 81%, and 72%, and 89%, 87% and 78% respectively. Factors on univariate analysis affecting technique survival included increasing age (HR 0.98, p = 0.04, 95% CI (0.96-0.999)), two or more episodes of PD-associated peritonitis (HR 4.52, p = 0.00, 95% CI (1.87-10.91)) and increasing PD intensity (HR 3.30, p = 0.02, 95% CI (1.22-8.93)). After multivariate adjustment which included baseline kidney function, low PD intensity continued to be associated with better technique survival (HR 0.17, p = 0.03, 95% CI (0.03-0.85)). CONCLUSION: Tailoring the PD prescription to RKF enables days off dialysis while still maintaining recommended levels of small solute clearance. This approach reduces dialysis burden and is associated with higher technique survival.
Subject(s)
Peritoneal Dialysis , Peritonitis , Humans , Peritoneal Dialysis/adverse effects , Peritonitis/epidemiology , Peritonitis/etiology , Prescriptions , Renal Dialysis , Retrospective StudiesABSTRACT
Haemodialysis remains the most widely used treatment for patients with end-stage renal disease. Despite the progress that has occurred in the treatment of end-stage renal disease over the last six decades, there has been a failure to translate this into the desired clinical benefits, with morbidity and mortality rates among patients on haemodialysis remaining unacceptably high. Recently, however, there have been expectations that the significant advances that took place over the last few years may result in improved outcomes. New medications for the treatment of anaemia and secondary hyperparathyroidism, as well as novel trends in the areas of iron therapy, diabetes management and physical exercise are among the most important advances which, taken together, are changing the standards of care for patients on haemodialysis. The latest advances, of relevance not only to specialists in Renal Medicine but also to general practitioners caring for these patients, are reviewed in this collaborative paper.
Subject(s)
Disease Management , Kidney Failure, Chronic/therapy , Renal Dialysis/adverse effects , Anemia/drug therapy , Anemia/etiology , Diabetes Mellitus/therapy , Exercise , Humans , Hyperparathyroidism/drug therapy , Hyperparathyroidism/etiology , Iron/therapeutic useABSTRACT
The effect of percutaneous kidney biopsy on glomerular filtration rate has never been identified, though it is frequently a concern raised by patients. Following a clinical interaction with an inquisitive patient undergoing her fifth biopsy, we attempted to estimate the effect using retrospective data. In a cohort of patients with stable kidney function undergoing transplant biopsy without clinical indication (as part of a surveillance programme) the effect of biopsy was observed as a step change in glomerular filtration rate. Reassuringly, the loss of glomerular filtration rate resulting from a biopsy, has a 1-sided 95% confidence interval of <1.4 mL/min.
ABSTRACT
BACKGROUND: During the coronavirus disease 2019 (COVID-19) epidemic, many countries have instituted population-wide measures for social distancing. The requirement of patients on dialysis for regular treatment in settings typically not conducive to social distancing may increase their vulnerability to COVID-19. METHODS: Over a 6-week period, we recorded new COVID-19 infections and outcomes for all adult patients receiving dialysis in a large dialysis center. Rapidly introduced control measures included a two-stage routine screening process at dialysis entry (temperature and symptom check, with possible cases segregated within the unit and tested for SARS-CoV-2), isolated dialysis in a separate unit for patients with infection, and universal precautions that included masks for dialysis nursing staff. RESULTS: Of 1530 patients (median age 66 years; 58.2% men) receiving dialysis, 300 (19.6%) developed COVID-19 infection, creating a large demand for isolated outpatient dialysis and inpatient beds. An analysis that included 1219 patients attending satellite dialysis clinics found that older age was a risk factor for infection. COVID-19 infection was substantially more likely to occur among patients on in-center dialysis compared with those dialyzing at home. We observed clustering in specific units and on specific shifts, with possible implications for aspects of service design, and high rates of nursing staff illness. A predictive epidemic model estimated a reproduction number of 2.2; cumulative cases deviated favorably from the model from the fourth week, suggesting that the implemented measures controlled transmission. CONCLUSIONS: The COVID-19 epidemic affected a large proportion of patients at this dialysis center, creating service pressures exacerbated by nursing staff illness. Details of the control strategy and characteristics of this epidemic may be useful for dialysis providers and other institutions providing patient care.
Subject(s)
Coronavirus Infections/complications , Coronavirus Infections/epidemiology , Infection Control/methods , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/therapy , Pneumonia, Viral/complications , Pneumonia, Viral/epidemiology , Aged , Betacoronavirus , COVID-19 , Electronic Health Records , Female , Fever/complications , Humans , London , Male , Middle Aged , Pandemics , Patient Isolation , Proportional Hazards Models , Quarantine , Renal Dialysis/adverse effects , Risk Factors , SARS-CoV-2 , Urban Health Services/organization & administrationABSTRACT
The 2019 International Society for Peritoneal Dialysis (ISPD) Practice Recommendations were prepared by a committee invited by the ISPD to develop new practice recommendations for prescribing high-quality, goal-directed peritoneal dialysis (PD). Further input was sought at the stage of the first draft of the proposed recommendations by circulating drafts of the recommendations and articles to an international selection of people who were either actively doing PD or who were previously treated with PD, as well as caregivers, to ask for their feedback. A diverse group of 22 people from 8 countries across 5 continents provided their feedback covering the main recommendations as well as the accompanying articles. Much of the feedback has been acted upon at the revision stages, however, the responses are published here in summary form to underscore the commitment to hearing the voice of those doing PD or caring for them. A key change that arose from the feedback has been the shift of language from "patient-centred" to "person-centered," reflecting the desire of these recommendations to address the patient as a person with needs and preferences beyond just the medical perspective, along with the need for the person doing PD to be central to the process of shared decision-making. Notwithstanding the challenges of an international, multi-lingual population, with people doing PD in highly diverse geographic and economic environments, the next iteration of ISPD guidelines should consider the role of people doing PD and their carers in evidence-based coproduced guidelines, from the inception of the guidelines.
Subject(s)
Peritoneal Dialysis , Aged , Caregivers , Frail Elderly , HumansABSTRACT
Background:The most common complication of peritoneal dialysis (PD) is infection. Despite this, there are no clear guidelines for the management of repeat exit-site infection (ESI), and best practice is not known. We describe our unit's experience of repeat ESI and clinical outcomes in this cohort.Methods:Retrospective case note review of all PD patients with positive ESI swabs at our center between 1 January 2012 and 1 January 2018. Patients were included in the study if they had 2 or more ESI with the same organism within a 12-month period and an initial positive response to antibiotic therapy.Results:Overall, 31 of 248 patients had repeat ESI. The 2 most common causative organisms were Staphylococcus aureus (n = 16, 52%) and Pseudomonas aeruginosa (n = 10, 32%). Twenty (65%) patients developed subsequent peritonitis. The infection resolved with further antibiotics alone in 10 (32%) patients and in 6 patients after PD catheter exchange. The PD catheter was removed in 16 (52%) patients (including 5 after an initial catheter exchange) requiring transfer to hemodialysis (HD). Six (19%) patients died within 12 months of repeat ESI. Both repeat Pseudomonas aeruginosa and Staphylococcus aureus infections were associated with high rates of dialysis modality change (70% and 50%, respectively).Conclusion:We have developed the first definition for repeat ESI. Repeat ESI is clinically important and results in significant morbidity and mortality. Following repeat ESI, peritonitis rates are high and a significant number of patients switch dialysis modality. Studies are needed to determine whether interventions such as early catheter exchange would improve outcomes.
Subject(s)
Catheter-Related Infections/diagnosis , Catheter-Related Infections/epidemiology , Kidney Failure, Chronic/therapy , Peritoneal Dialysis/adverse effects , Peritonitis/microbiology , Adult , Aged , Female , Humans , Incidence , Kidney Failure, Chronic/complications , Male , Middle Aged , Recurrence , Retrospective Studies , Time FactorsABSTRACT
OBJECTIVES: To investigate changes in renal status from exercise in the heat with acclimatisation and to evaluate surrogates markers of Acute Kidney Injury. DESIGN: Prospective observational cohort study. METHODS: 20 male volunteers performed 60 min standardised exercise in the heat, at baseline and on four subsequent occasions during a 23-day acclimatisation regimen. Blood was sampled before and after exercise for serum creatinine, copeptin, interleukin-6, normetanephrine and cortisol. Fractional excretion of sodium was calculated for corresponding urine samples. Ratings of Perceived Exertion were reported every 5 min during exercise. Acute Kidney Injury was defined as serum creatinine rise ≥26.5 µmol L-1 or fall in estimated glomerular filtration rate >25%. Predictive values of each candidate marker for developing Acute Kidney Injury were determined by ROC analysis. RESULTS: From baseline to Day 23, serum creatinine did not vary at rest, but showed a significant (P<0.05) reduction post-exercise (120 [102, 139] versus 102 [91, 112] µmol L-1). Acute Kidney Injury was common (26/100 exposures) and occurred most frequently in the unacclimatised state. Log-normalised fractional excretion of sodium showed a significant interaction (exercise by acclimatization day), with post-exercise values tending to rise with acclimatisation. Ratings of Perceived Exertion predicted AKI (AUC 0.76, 95% confidence interval 0.65-0.88), performing at least as well as biochemical markers. CONCLUSIONS: Heat acclimatization is associated with reduced markers of renal stress and AKI incidence, perhaps due to improved regional perfusion. Acclimatisation and monitoring Ratings of Perceived Exertion are practical, non-invasive measures that could help to reduce renal injury from exercise in the heat.
Subject(s)
Acclimatization , Acute Kidney Injury/diagnosis , Exercise , Hot Temperature , Kidney/physiology , Acute Kidney Injury/physiopathology , Adult , Biomarkers/blood , Creatinine/blood , Glomerular Filtration Rate , Glycopeptides/blood , Humans , Hydrocortisone/blood , Interleukin-6/blood , Kidney/physiopathology , Male , Military Personnel , Normetanephrine/blood , Prospective Studies , Stress, Physiological , Young AdultABSTRACT
There has been a dramatic, worldwide expansion in life expectancy across the last century. This has resulted in a progressively more elderly and comorbid population. It is increasingly recognized that healthcare in this group needs to move to the concept of "adding life to years". Recognition and assessment of frailty is vital in changing our approach in elderly patients. Current guidelines in dialysis have a limited evidence base across all age groups, but particularly the elderly and serve them poorly. Moreover, the burden of guidelines for each comorbidity of the multimorbid patient is increasing and can be conflicting. Finally, there is increasing evidence relating to the harm associated with the delivery of conventional dialysis. In dialysis patients, frailty is the overwhelming determinant in relation to patient-specific outcomes rather than modality of treatment; therefore, the focus should be on promoting quality of life. We need to focus on new priorities of care when we design guidelines "for people not diseases". Patient-centered goal-directed therapy, arising from shared decision making between physician and patient, should allow adaption of the dialysis regime to maximize opportunities while minimizing treatment-related morbidity and concentrating on alleviating symptoms.
Subject(s)
Frailty/therapy , Kidney Failure, Chronic/therapy , Practice Guidelines as Topic , Renal Dialysis/methods , Aged , Humans , Renal Dialysis/adverse effectsABSTRACT
OBJECTIVE: Native arteriovenous fistulas (AVFs) for hemodialysis are susceptible to nonmaturation. Adverse features of local blood flow have been implicated in the formation of perianastomotic neointimal hyperplasia that may underpin nonmaturation. Whereas computational fluid dynamic simulations of idealized models highlight the importance of geometry on fluid and vessel wall interactions, little is known in vivo about AVF geometry and its role in adverse clinical outcomes. This study set out to examine the three-dimensional geometry of native AVFs and the geometric correlates of AVF failure. METHODS: As part of an observational study between 2013 and 2016, patients underwent creation of an upper limb AVF according to current surgical best practice. Phase-contrast magnetic resonance imaging was performed on the day of surgery to obtain luminal geometry along with ultrasound measurements of flow. Magnetic resonance imaging data sets were segmented and reconstructed for quantitative and qualitative analysis of local geometry. Clinical maturation was evaluated at 6 weeks. RESULTS: There were 60 patients who were successfully imaged on the day of surgery. Radiocephalic (n = 17), brachiocephalic (n = 40), and brachiobasilic (n = 3) fistulas were included in the study. Centerlines extracted from segmented vessel lumen exhibited significant heterogeneity in arterial nonplanarity and curvature. Furthermore, these features are more marked in brachiocephalic than in radiocephalic fistulas. Across the cohort, the projected bifurcation angle was 73 ± 16 degrees (mean ± standard deviation). Geometry was preserved at 2 weeks in 20 patients who underwent repeated imaging. A greater degree of arterial nonplanarity (log odds ratio [logOR], 0.95 per 0.1/vessel diameter; 95% confidence interval [CI], 0.22-1.90; P = .03) and a larger bifurcation angle (logOR, 0.05 per degree; 95% CI, 0.01-0.09; P = .02) are associated with a greater rate of maturation, as is fistula location (upper vs lower arm; logOR, -1.9; 95% CI, -3.2 to 0.7; P = .002). CONCLUSIONS: There is significant heterogeneity in the three-dimensional geometry of AVFs, in particular, arterial nonplanarity and curvature. In this largest cohort of AVF geometry to date, the effect of individual geometric correlates on maturation is uncertain but supports the premise that future modeling studies will need to acknowledge the complex geometry of AVFs.
Subject(s)
Arteriovenous Shunt, Surgical/methods , Brachial Artery/surgery , Radial Artery/surgery , Renal Dialysis , Upper Extremity/blood supply , Adult , Aged , Arteriovenous Shunt, Surgical/adverse effects , Blood Flow Velocity , Brachial Artery/diagnostic imaging , Brachial Artery/physiopathology , Female , Humans , Magnetic Resonance Angiography , Male , Middle Aged , Models, Cardiovascular , Patient-Specific Modeling , Prospective Studies , Radial Artery/diagnostic imaging , Radial Artery/physiopathology , Regional Blood Flow , Treatment Failure , Ultrasonography, DopplerABSTRACT
Five days following the 3rd cycle of nivolumab, a monoclonal antibody, which acts as immune checkpoint inhibitor against the programmed cell death protein-1, for metastatic lung adenocarcinoma, a 56-year-old woman presented at the hospital critically ill. On admission, she had severe diabetic ketoacidosis (DKA), as evidenced by venous glucose of 47 mmol/L, blood ketones of 7.5 mmol/L, pH of 6.95 and bicarbonate of 6.6 mmol/L. She has had no personal or family history of diabetes mellitus (DM), while random venous glucose, measured 1 week prior to hospitalisation, was 6.1 mmol/L. On admission, her HbA1c was 8.2% and anti-GAD antibodies were 12 kIU/L (0-5 kU/L), while islet cell antibodies and serum C-peptide were undetectable. Nivolumab was recommenced without the development of other immune-mediated phenomena until 6 months later, when she developed hypothyroidism with TSH 18 U/L and low free T4. She remains insulin dependent and has required levothyroxine replacement, while she has maintained good radiological and clinical response to immunotherapy. This case is notable for the rapidity of onset and profound nature of DKA at presentation, which occurred two months following commencement of immunotherapy. Despite the association of nivolumab with immune-mediated endocrinopathies, only a very small number of patients developing type 1 DM has been reported to date. Patients should be closely monitored for hyperglycaemia and thyroid dysfunction prior to and periodically during immunotherapy. LEARNING POINTS: Nivolumab can induce fulminant type 1 diabetes, resulting in DKA.Nivolumab is frequently associated with thyroid dysfunction, mostly hypothyroidism.Nivolumab-treated patients should be monitored regularly for hyperglycaemia and thyroid dysfunction.Clinicians should be aware and warn patients of potential signs and symptoms of severe hyperglycaemia.