The interdialytic weight gain: a simple marker of left ventricular hypertrophy in children on chronic haemodialysis

Machine learning models to predict post-dialysis blood pressure in children and young adults on maintenance hemodialysis

Hypertension is associated with significant cardiovascular morbidity. Blood pressure (BP) control on maintenance hemodialysis (HD) is strongly impacted by volume status. The objective of this study was to assess whether machine learning (ML) is effective in predicting post-HD BP in children and young adults on HD. We collected data on BP, IDWG, pulse, and weights for patients on maintenance HD (> 3 months). Input features included DW, pre-post weight difference, IDWG and pre-HD BP. Seven models were trained and tuned using open-source libraries. Model performance was evaluated using time-series cross-validation on a rolling basis (3-12 month training, 1-day testing). Various regression scores were compared between models. Data for 35 patients (14,375 HD sessions) were analyzed. Extreme gradient boosting (XGB) and vector autoregression with exogenous regressors (VARX) achieved better accuracy in predicting post-dialysis systolic BP than K-nearest neighbor, support vector regression (SVR) with radial basis function kernel and random forest (p < 0.001 for each). The differences in accuracy between XGB, VARX, SVR with linear kernel, random forest and linear regression were not significant. Using clinical parameters, ML models may be useful in predicting post-HD BP, which may help guide DW adjustment and optimizing BP control for maintenance HD patients.

Developing a trigger tool to monitor adverse events during haemodialysis in children: a pilot project

BACKGROUND

We developed a paediatric haemodialysis trigger tool (pHTT) for application per haemodialysis (HD) session in children receiving intermittent in-centre HD and systematically monitored adverse events.

METHODS

Single-centre quality improvement study performed over two 8-week cycles. Data collected prospectively using a 'per-dialysis session' pHTT tool including 54 triggers across six domains, adapted from a recently described haemodialysis trigger tool (HTT) for adults. Each trigger was evaluated for level of harm following assessment by two authors. Following a period of training, HD nurses completed the HTT at the end of each dialysis session.

RESULTS

There were 241 triggers over 182 dialysis sessions, with 139 triggers in 91 HD sessions for 15 children, age range 28-205 months, over an 8-week period (first cycle) and 102 triggers in 91 HD sessions for 13 children, age range 28-205 months, over a further 8-week period (second cycle). After interventions informed by the pHTT, the harm rate per session was significantly reduced from 1.03 (94/91) to 0.32 (29/91), P < 0.001. There was a significant difference between the distribution of triggers by harm category (P < 0.001) and between the proportion of triggers across the various domains of the pHTT (P = 0.004) between the two cycles. No triggers were evaluated as causing permanent harm.

CONCLUSIONS

This pilot study demonstrates potential benefits of a bedside tool to monitor adverse events during haemodialysis in children. Thus, following interventions informed by the pHTT, the harm rate per session was significantly reduced. Under standard patient safety systems, the vast majority of triggers identified by the pHTT would remain unreported and perhaps lead to missed opportunities to improve patient safety. We propose the use of a paediatric HTT as part of standard care by centres providing HD to children in the future. A higher resolution version of the Graphical abstract is available as Supplementary information.

Chronic haemodialysis in infants and children less than 15 kg

BACKGROUND

Peritoneal dialysis (PD) is the most commonly used kidney replacement therapy in infants and young children with chronic kidney disease (CKD) stage 5. Chronic haemodialysis (cHD) is the alternative treatment when PD is not possible for technical reasons; however, the difficulties that may be encountered are challenging and require clinicians with specialist training and experience. This study aims to describe the clinical history, complications and outcomes in children < 15 kg on cHD.

METHODS

A retrospective, descriptive study of the clinical records of patients weighing < 15 kg on cHD for more than 3 months. The reasons for CKD stage 5, age at start of treatment, duration of haemodialysis, anthropometric and metabolic variables, as well as vascular access, complications and clinical outcome were recorded.

RESULTS

Fifteen patients were included between 2006 and 2018 with a median age at start of cHD of 30 (interquartile range (IQR) 13, 39) months and median duration of 15 (IQR 7.5, 25.3) months. Five patients were younger than 2 years. The median weight at start of treatment was 11.2 (IQR 6.4, 12.8) kg. Forty-five tunneled catheters with a median survival of 106 days were used. The main cause of loss of vascular access was obstruction or displacement dysfunction (39%). The catheter-associated infection rate was 0.76 per 1000 catheter days. Ten patients received a successful kidney transplant, 4 were transferred to PD and one died from complications during abdominal surgery.

CONCLUSIONS

cHD can be successfully performed in children < 15 kg by addressing specific clinical and technical issues.

Nutritional status and volume control in adolescents on chronic hemodialysis

BACKGROUND

Pediatric patients on maintenance hemodialysis (HD) are at risk of both malnutrition and fluid overload. This pilot study aimed to assess correlates of normalized protein catabolic rate (nPCR) in adolescents on chronic HD, in particular fluid status markers.

METHODS

All patients aged 10-18 years on chronic HD in our center between 2017 and 2019 were enrolled. For each patient, mean nPCR was calculated and correlations with the following parameters investigated: dry body weight change in subsequent 3 months in kg (∆BW) and percentage of BW (∆BW%), change in body mass index (∆BMI), preHD systolic and diastolic blood pressure (SBP, DBP), residual urine output, biochemistry, and blood volume monitoring-derived first hour refill index (RI), calculated as ratio between ultrafiltration rate and reduction in relative blood volume in first hour of dialysis.

RESULTS

Seventy-nine nPCR determinations were collected in 23 patients, median age 14.8 years. nPCR significantly correlated with ∆BW, ∆BW%, ∆BMI, spKT/V, and preHD serum creatinine, and negatively correlated with age, DBP SDS (r=-0.466, p=0.025) and RI (r=-0.435, p=0.043). RI was significantly higher in patients with nPCR <1 than those with nPCR above this threshold: 3.2 (1.9-4.7) vs. 1.4 (0.7-1.8) ml/kg/h/% (p=0.021). At multivariable analysis, nPCR remained positively correlated with creatinine and spKt/V, and inversely correlated with RI.

CONCLUSIONS

nPCR is a significant predictor of weight change in adolescents on maintenance HD, and seems associated with creatinine and dialysis adequacy. Inverse correlation with RI suggests possible associations between malnutrition and fluid overload, but larger prospective studies are needed to confirm this. A higher resolution version of the Graphical abstract is available as Supplementary information.

Nutritional Assessment and Management in Paediatric Chronic Kidney Disease

Nutrition in paediatrics has always been one of the most important factors for optimal growth. Children with chronic kidney disease (CKD) need special consideration for better long-term outcomes, including nutritional status, optimal height, and cognitive function. Nonetheless, there are many obstacles to overcome to attain optimal linear growth and nutritional status in children with CKD. This review highlights the need for tools to assess the growth parameters in CKD. In addition, recommendations for dietary intake play a major role in controlling electrolyte disturbances in patients with CKD. For example, it is still unclear whether it is better to restrict phosphate sources in inorganic, organic, or food additives. The review also summarises different factors such as fluid intake, route of feeding, and essential nutrients that require particular attention in paediatric patients with CKD. In summary, a multidisciplinary team is needed to devise individual nutritional plans to achieve the best outcome and improve the quality of life of patients.

Bedside sonographic assessments for predicting predialysis fluid overload in children with end-stage kidney disease

Although the number of studies evaluating methods to predict fluid overload is increasing, the assessment of fluid status in children on dialysis is still fraught with inaccuracies. We aimed to evaluate the predictive capability of lung ultrasounds and the inferior vena cava collapsibility index (cIVC) in predialysis overhydration in children with end-stage kidney disease. Ten children with end-stage kidney disease who were on an intermittent hemodialysis program were included. The hydration status of the patients was clinically evaluated. Moreover, 30 predialysis and 30 postdialysis lung ultrasound, cIVC, and bioimpedance spectroscopy (BIS) measurements were performed. The median age of the participants was 14 (IQR, 13-15) years, and two (20%) were male. There was a strong positive correlation between the predialysis total number of B-lines and predialysis fluid overload (r=0.764, p<0.001). Additionally, there was a moderate negative correlation between predialysis cIVC and predialysis fluid overload (r=-0.599, p=0.002). Although the moderate correlation was determined between the postdialysis fluid overload and total number of B-lines, no correlation was determined using cIVC. Receiver operating characteristic curves demonstrated that the total number of B-lines and cIVC could successfully predict the predialysis fluid overload (relative hydration >7% derived from the BIS; AUROC 0.82 and 0.80, respectively). When both evaluations were combined, if either the total number of B-lines or the cIVC was outside the corresponding cutoff range (>10.5 and ≤23.5, respectively), it was detected in 16 out of 17 sessions (sensitivity 94%). If either one was outside the corresponding cutoff range (total number of B-lines >10.5 and cIVC ≤18.2), the severe predialysis fluid overload was predicted successfully in all eight (100%) sessions. Conclusion: Randomized controlled studies are needed to prove the reliability of the combined use of lung ultrasounds and cIVC in the assessment of predialysis fluid overload. What is Known: • The association of chronic fluid overload with increased morbidity and mortality raises the need for optimal determination of fluid overload in pediatric patients who are dialysis-dependent at a young age. • The linear correlation between the total number of B-lines on lung ultrasound images and fluid overload by weight has been shown. What is New: • This study evaluates the lung ultrasound and inferior vena cava collapsibility index combined in predicting fluid overload in dialytic children. • If either the total number of B-lines or the cIVC was outside the corresponding cutoff range (>10.5 and cIVC ≤18.2, respectively), the severe predialysis fluid overload was predicted successfully in all eight (100%) sessions.

Children on chronic hemodialysis before the first year of age in Brazil: A 3-year survival analysis

INTRODUCTION

The limited data on survival rates of small children undergoing hemodialysis preclude comparison with other countries. The goal of this study was to determine the mortality rate and its risk factors in children starting hemodialysis during their first year of life.

METHODS

We performed a retrospective cohort study, based on data from a reference dialysis center in São Paulo city. Data from 47 (8 females) children who underwent chronic hemodialysis before the first year of age were analyzed. Survival was characterized using Kaplan-Meier methods and log-rank tests, followed by a multivariable Cox regression model.

RESULTS

The survival rates were 93%, 75%, and 64% at 1, 2, and 3 years, respectively. Only cardiovascular comorbidity was significantly associated with the mortality outcome (HR = 5.7, 95% CI = 1.7-19.6, p = 0.006).

CONCLUSION

The survival rate among children who started hemodialysis in their first year of life was reasonable, similar to international standards.

Hemodiafiltration maintains a sustained improvement in blood pressure compared to conventional hemodialysis in children-the HDF, heart and height (3H) study

BACKGROUND

Hypertension is prevalent in children on dialysis and associated with cardiovascular disease. We studied the blood pressure (BP) trends and the evolution of BP over 1 year in children on conventional hemodialysis (HD) vs. hemodiafiltration (HDF).

METHODS

This is a post hoc analysis of the "3H - HDF-Hearts-Height" dataset, a multicenter, parallel-arm observational study. Seventy-eight children on HD and 55 on HDF who had three 24-h ambulatory BP monitoring (ABPM) measures over 1 year were included. Mean arterial pressure (MAP) was calculated and hypertension defined as 24-h MAP standard deviation score (SDS) ≥95th percentile.

RESULTS

Poor agreement between pre-dialysis systolic BP-SDS and 24-h MAP was found (mean difference - 0.6; 95% limits of agreement -4.9-3.8). At baseline, 82% on HD and 44% on HDF were hypertensive, with uncontrolled hypertension in 88% vs. 25% respectively; p < 0.001. At 12 months, children on HDF had consistently lower MAP-SDS compared to those on HD (p < 0.001). Over 1-year follow-up, the HD group had mean MAP-SDS increase of +0.98 (95%CI 0.77-1.20; p < 0.0001), whereas the HDF group had a non-significant increase of +0.15 (95%CI -0.10-0.40; p = 0.23). Significant predictors of MAP-SDS were dialysis modality (β = +0.83 [95%CI +0.51 - +1.15] HD vs. HDF, p < 0.0001) and higher inter-dialytic-weight-gain (IDWG)% (β = 0.13 [95%CI 0.06-0.19]; p = 0.0003).

CONCLUSIONS

Children on HD had a significant and sustained increase in BP over 1 year compared to a stable BP in those on HDF, despite an equivalent dialysis dose. Higher IDWG% was associated with higher 24-h MAP-SDS in both groups.

Hemodialysis (HD) dose and ultrafiltration rate are associated with survival in pediatric and adolescent patients on chronic HD-a large observational study with follow-up to young adult age

BACKGROUND

Hemodialysis (HD) dose targets and ultrafiltration rate (UFR) limits for pediatric patients on chronic HD are not known and are derived from adults (spKt/V>1.4 and <13 ml/kg/h). We aimed to characterize how delivered HD dose and UFR are associated with survival in a large cohort of patients who started HD in childhood.

METHODS

Retrospective analysis on a cohort of patients <30 years, on chronic HD since childhood (<19 years), having received thrice-weekly HD 2004-2016 in outpatient DaVita centers.

OUTCOME

Survival while remaining on HD.

PREDICTORS

(I) primary analysis: mean delivered dialysis dose stratified as spKt/V ≤1.4/1.4-1.6/>1.6 (Kaplan-Meier analysis), (II) secondary analyses: UFR and alternative dialysis adequacy measures [eKt/V, body-surface normalized Kt/BSA] on continuous scale (Weibull regression model).

RESULTS

A total of 1780 patients were included (age at the start of HD: 0-12y: n=321, >12-18y: n=1459; median spKt/V=1.55, eKt/V=1.31, Kt/BSA=31.2 L/m², UFR=10.6 mL/kg/h). (I) spKt/V<1.4 was associated with lower survival compared to spKt/V>1.4-1.6 (P<0.001, log-rank test), and spKt/V>1.6 (P<0.001), with 10-year survival of 69.3% (59.4-80.9%) versus 83.0% (76.8-89.8%) and 84.0% (79.6-88.5%), respectively. (II) Kt/BSA was a better predictor of survival than spKt/V or eKt/V. UFR was additionally associated with survival (P<0.001), with increased mortality <10/>18 mL/kg/h. Associations did not alter significantly following adjustment for demographic characteristics (age, etiology of kidney disease, and ethnicity).

CONCLUSIONS

Our results suggest usefulness of targeting Kt/BSA>30 L/m² for best long-term outcomes, corresponding to spKt/V>1.4 (>12 years) and >1.6 (<12 years). In contrast to adults, higher UFR of 10-18 ml/kg/h was not associated with greater mortality in this population.

Canadian Association of Paediatric Nephrologists COVID-19 Rapid Response: Home and In-Center Dialysis Guidance

PURPOSE OF THE PROGRAM

This article provides guidance on optimizing the management of pediatric patients with end-stage kidney disease (ESKD) who will be or are being treated with any form of home or in-center dialysis during the COVID-19 pandemic. The goals are to provide the best possible care for pediatric patients with ESKD during the pandemic and ensure the health care team's safety.

SOURCES OF INFORMATION

The core of these rapid guidelines is derived from the Canadian Society of Nephrology (CSN) consensus recommendations for adult patients recently published in the Canadian Journal of Kidney Health and Disease (CJKHD). We also consulted specific documents from other national and international agencies focused on pediatric kidney health. Additional information was obtained by formal review of the published academic literature relevant to pediatric home or in-center hemodialysis.

METHODS

The Leadership of the Canadian Association of Paediatric Nephrologists (CAPN), which is affiliated with the CSN, solicited a team of clinicians and researchers with expertise in pediatric home and in-center dialysis. The goal was to adapt the guidelines recently adopted for Canadian adult dialysis patients for pediatric-specific settings. These included specific COVID-19-related themes that apply to dialysis in a Canadian environment, as determined by a group of senior renal leaders. Expert clinicians and nurses with deep expertise in pediatric home and in-center dialysis reviewed the revised pediatric guidelines.

KEY FINDINGS

We identified 7 broad areas of home dialysis practice management that may be affected by the COVID-19 pandemic: (1) peritoneal dialysis catheter placement, (2) home dialysis training, (3) home dialysis management, (4) personal protective equipment, (5) product delivery, (6) minimizing direct health care providers and patient contact, and (7) caregivers support in the community. In addition, we identified 8 broad areas of in-center dialysis practice management that may be affected by the COVID-19 pandemic: (1) identification of patients with COVID-19, (2) hemodialysis of patients with confirmed COVID-19, (3) hemodialysis of patients not yet known to have COVID-19, (4) management of visitors to the dialysis unit, (5) handling COVID-19 testing of patients and staff, (6) safe practices during resuscitation procedures in a pandemic, (7) routine hemodialysis care, and (8) hemodialysis care under fixed dialysis resources. We make specific suggestions and recommendations for each of these areas.

LIMITATIONS

At the time when we started this work, we knew that evidence on the topic of pediatric dialysis and COVID-19 would be severely limited, and our resources were also limited. We did not, therefore, do formal systematic review or meta-analysis. We did not evaluate our specific suggestions in the clinical environment. Thus, this article's advice and recommendations are primarily expert opinions and subject to the biases associated with this level of evidence. To expedite the publication of this work, we created a parallel review process that may not be as robust as standard arms' length peer-review processes.

IMPLICATIONS

We intend these recommendations to help provide the best care possible for pediatric patients prescribed in-center or home dialysis during the COVID-19 pandemic, a time of altered priorities and reduced resources.

Clinical Relevance of Fluid Volume Status Assessment by Bioimpedance Spectroscopy in Children Receiving Maintenance Hemodialysis or Peritoneal Dialysis

Bioimpedance spectroscopy (BIS) is a noninvasive method used to evaluate body fluid volume status in dialysis patients, but reports on its effectiveness in pediatrics are scarce. We investigated the correlation between BIS and clinical characteristics and identified the changes in patients whose dialysis prescription was modified based on BIS. The medical records of children on maintenance dialysis who had undergone BIS between 2017 and 2019 were reviewed. Of the 49 patients, 14 were overhydrated, based on the >15% proportion of overhydration relative to extracellular water (OH/ECW) measured by BIS. Intake of ≥two antihypertensive medications was noted in the majority (85.7%) of children with fluid overload and only in 48.6% of those without fluid overload (p = 0.017). Elevated blood pressure despite medication use was significantly more common in patients with fluid overload than in those without fluid overload (78.6% vs. 45.7%, p = 0.037). Of the 14 overhydrated children, 13 (92.9%) had significant changes in body weight, OH/ECW, the number of antihypertensive drugs, left ventricular end-diastolic diameter, and cardiothoracic ratio after the change in dialysis prescription. BIS is a useful and noninvasive method to assess fluid status in dialysis children. Long-term follow-up and correlation with a more objective clinical indicator of fluid overload is necessary to verify the clinical effectiveness of BIS.

Tracking hydration status changes by bioimpedance spectroscopy in children on peritoneal dialysis

BACKGROUND

This 6-month prospective longitudinal study investigates the association between hydration status changes using bioimpedance spectroscopy (BIS) and systolic blood pressure (SBP), pulse pressure (PP), and serum albumin (sAlb) changes in children on peritoneal dialysis (PD).

METHODS

Thirteen patients (median age: 12.58 years) were enrolled. Normal hydration, moderate hydration, severe overhydration, and dehydration were defined as -7% ≤ relative overhydration (Re-OH) < +7%, +7% ≤ Re-OH < +15%, Re-OH ≥ +15%, and Re-OH < -7%, respectively. Automated office blood pressure z-score, sAlb, and weight z-score were recorded.

RESULTS

Fifty-two Re-OH measurements were recorded: three in five, four in five, five in two, and seven in one patient, respectively. SBP was higher and sAlb lower in cases with severe overhydration (9 readings) (p < 0.001, p < 0.001), but distribution of these parameters did not differ between normal hydration/dehydration (28 readings) and moderate overhydration (15 readings) cases. In patients with hydration status change, SBP and PP were higher while sAlb lower in cases with higher hydration status level (p = 0.026, p = 0.05, and p = 0.109, respectively). In all patients, visit-to-visit SBP, PP, and sAlb changes were correlated to Re-OH changes (rs = 0.693, p < 0.001; rs = 0.643, p < 0.001; rs = -0.444, p = 0.008, respectively) but not to weight changes (rs = 0.052, p = 0.754; rs = 0.034, p = 0.838; rs = -0.156, p = 0.378, respectively). Visit-to-visit Re-OH changes, which were >+4% or <-4%, were linearly correlated to SBP (r = 0.858, p < 0.001), PP (r = 0.757, p < 0.001), and sAlb (r = -0.699, p = 0.002) changes.

CONCLUSION

In children on PD, longitudinal Re-OH changes are superior to weight changes in assessing volume-dependent variations of SBP, PP, and sAlb. Routine BIS application, rather than single BIS measurements, seems useful in the intra-patient monitoring of hydration status.

Improved blood pressure and left ventricular remodelling in children on chronic intermittent haemodialysis: a longitudinal study

OBJECTIVES

We aimed to examine longitudinal changes in left ventricular (LV) structure and function and evaluate factors associated with LV remodelling in children on chronic haemodialysis.

METHODS

Retrospective longitudinal study including all children from the start of chronic haemodialysis with two or more m-mode 2D echocardiograms and tissue Doppler studies. Left ventricular mass (LVM) in g/m^2.7, geometry and LV function were compared at baseline (dialysis start) with follow-up studies at least 6 months following commencement. Left ventricular hypertrophy (LVH) was defined if greater than 95th percentile as per age-specific centiles. We also defined LVH as indexed LV mass index (LVMI) > 51 g/m^2.7 and using LV mass-for-height z-scores greater than the 95th percentile. Biochemical data, interdialytic weight change and blood pressure level were assessed for their association with change in indexed LVM.

RESULTS

Twenty-three of the 32 children < 18 years were included (n = 5, < 5 years) with last follow-up study performed following dialysis after a median (IQR) of 21 (10-34) months. The prevalence of LVH reduced significantly (69.6%, (n = 16/23) vs. 39.1% (n = 9/23), P = 0.002); LV geometry improved (13% concentric and 56.5% eccentric vs. 8.7% and 17.4% respectively) with mean ± SD reduction in indexed LVM (50.8 ± 23.1 g/m^2.7 vs. 38.6 ± 14.7 g/m^2.7, P = 0.002) and LV mass-for-height z-scores (0.67 ± 1.66 vs. - 0.46 ± 1.88, P = 0.002) from baseline to last follow-up respectively. There was no change in systolic function (LV fractional shortening, 37% vs. 38%, P = 0.39) and diastolic function (mean E/E' 10.8 vs. 9.0, P = 0.09). Multiple regression analysis identified improved systolic BP control (β = 0.41, P = 0.04) as an independent predictor for change in indexed LVM.

CONCLUSIONS

LV structure and function can improve in children despite long-term chronic intermittent haemodialysis. Cardiovascular health in this population does not always deteriorate but can be stabilised and indeed improved with optimal blood pressure management.

Comparing the accuracy of cone-beam computed tomography and electronic apex locator for root canal length determination in primary teeth

AIMS

The aims of this study were to assess the accuracy of electronic apex locator (CanalPro™) and cone-beam computed tomography (CBCT) in determination of working length in primary teeth compared to direct visual length.

SUBJECTS AND METHODS

Ninety-nine primary teeth (207 root canals) were subjected to CBCT scan for assessment of working length. All root canals were then measured using CanalPro™ Apex Locator. Actual length of root canal was measured using direct visual method which was kept as control.

STATISTICAL ANALYSIS USED

One-way ANOVA and Tukey's honestly significant difference tests were performed using the Statistical Packages for the Social Sciences (SPSS) version 16.

RESULTS

Overall estimated mean values obtained using three methods show that CBCT method was more accurate than the apex locator in determining the working length in primary teeth. However, these values were statistically insignificant.

CONCLUSIONS

CanalPro™ Apex Locator can be used in primary teeth to accurately determine the working length. Nevertheless, a preexisting CBCT can always be used for determination of the working length in the primary teeth.

Assessment and management of fluid overload in children on dialysis

Dysregulation of intravascular fluid leads to chronic volume overload in children with end-stage kidney disease (ESKD). Sequelae include left ventricular hypertrophy and remodeling and impaired cardiac function. As a result, cardiovascular complications are the commonest cause of mortality in the pediatric dialysis population. The clinical need to optimize intravascular volume in children with ESKD is clear; however, its assessment and management is the most challenging aspect of the pediatric dialysis prescription. Minimizing chronic fluid overload is a key priority; however, excessive ultrafiltration is toxic to the myocardium and can precipitate intradialytic symptoms. This review outlines emerging objective techniques to enhance the assessment of fluid overload in children on dialysis and outlines evidence for current management strategies to address this clinical problem.

Interdialytic weight gain and vasculopathy in children on hemodialysis: a single center study

BACKGROUND

Increased interdialytic weight gain (IDWG) has been associated with poor outcomes in adults, but its impact on hemodialysis vasculopathy in children is unknown.

METHODS

Nineteen patients (age 9 to 19 years old) with a median hemodialysis duration of 10.4 months were enrolled. Cardiovascular evaluation included left ventricular mass index (LVMI), pulse wave velocity (PWV), and carotid intima-media thickness (cIMT) measurements. PWV and cIMT were expressed as z-scores based on reference values in healthy children. Blood pressure (BP) evaluation consisted in a 24-h ambulatory BP monitoring. Mean IDGW and residual urine output during the 6 months prior to cardiovascular examination were calculated.

RESULTS

Increased cIMT, LVMI, and PWV was observed in 11 (57.9%), 7 (36.8%), and 5 (26.3%) patients respectively, while BP was normal in all patients. Median IDWG was 3.5% (1.8-6.7). Residual urine output and BP status did not significantly differ between patients with IDWG ≥ or < 4%. After linear regression, IDWG was correlated to cIMT z-score (r² = 0.485, p = 0.001), but not to PWV z-score (r² = 0.04, p = 0.415) and LVMI (r² = 0.092, p = 0.206). After univariate logistic regression, IDWG ≥ 4% was significantly associated to increased cIMT (above 1.65 SDS) (odds ratio 12.25, 95% confidence interval 1.08-138.988). The trend toward an increased cIMT with IDWG ≥ 4% was observed in both patients with short and long dialysis vintage.

CONCLUSIONS

High IDWG is associated with increased cIMT in hemodialyzed children independently of BP control and dialysis vintage. This observation reinforces the importance of interventions to avoid IDWG in hemodialyzed children.

Artificial intelligence outperforms experienced nephrologists to assess dry weight in pediatric patients on chronic hemodialysis

BACKGROUND

Dry weight is the lowest weight patients on hemodialysis can tolerate; correct dry weight estimation is necessary to minimize morbi-mortality, but is difficult to achieve. Here, we used artificial intelligence to improve the accuracy of dry weight assessment in hemodialysis patients.

METHODS/RESULTS

We designed a neural network which used bio-impedancemetry, blood volume monitoring, and blood pressure values as inputs; output was artificial intelligence dry weight. Fourteen pediatric patients were switched from nephrologist to artificial intelligence dry weight. Artificial intelligence dry weight was higher (28.6%), lower (50%), or identical to nephrologist dry weight. Mean difference between artificial intelligence and nephrologist dry weights was 0.497 kg (- 1.33 to + 1.29 kg). In patients for whom artificial intelligence dry weight was lower than nephrologist dry weight, systolic blood pressure significantly decreased after dry weight decrease to artificial intelligence dry weight (77th to 60th percentile, p = 0.022); anti-hypertensive treatments were successfully decreased or discontinued in 28.7% of cases. In patients for whom artificial intelligence dry weight was higher than nephrologist dry weight, no hypertension was observed after dry weight increase to artificial intelligence dry weight; when present, symptoms of dry weight underestimation receded.

CONCLUSIONS

Neural network predictions outperformed those of experienced nephrologists in most cases, proving artificial intelligence is a powerful tool for predicting dry weight in hemodialysis patients.

Age- and weight-based differences in haemodialysis prescription and delivery in children, adolescents and young adults

Background

Limited systematic data are available on prescription and dosing of haemodialysis (HD) in children and adolescents compared with adults. We aimed to characterize age- and weight-based differences in HD delivery in children, adolescents and young adults.

Methods

This is a retrospective observational study including 1852 patients <30 years on chronic HD from childhood (53 903 HD sessions), receiving thrice weekly outpatient HD between 2004 and 2016 in the USA (6075 patient-years, of which 2535 were in patients aged 1-18 years; weight range 8.3-168 kg). Median individual prescriptions per year were calculated and overall 50% (IQR) and 90% distribution ranges over age and weight were derived. Repeated measurements analysis of variance assessed differences between age and weight groups.

Results

Prescriptions significantly differed among age and weight groups (P < 0.001). Lower weight patients (<75 kg) had higher (inter-quartile range, IQR) weight-normalized blood flow rate (highest in <25 kg: QB/kg = 6.5-9.1 mL/min/kg), urea dialytic clearance (KD/kg) and single pool Kt/V (spKt/V) (<25 kg: 1.43-1.78; 25-50 kg: 1.52-1.92; 50-75 kg: 1.43-1.74) than heavier patients (lowest in >100 kg: QB/kg = 3.1-4.0 mL/min/kg, spKt/V = 1.22-1.47, respectively). Adolescents had significantly lower QB/kg, KD/kg and spKt/V (1.34-1.71) compared with adults (1.45-1.79) and children <12 years (range of 25th percentiles: 1.37-1.44). Dialytic clearance derived from a mechanistic equation underpredicted KD in children but not in young adults. Significant growth retardation was observed, with the proportion of patients <3rd percentile (height for age) decreasing from 71% (1-2 years) to 15% (>18 years).

Conclusion

Delivered HD treatment varies with age and weight and is more intensified in children aged <12 years, compared with adolescents and overweight young adults, who appear to be at highest risk of receiving suboptimal treatment. Still, delivery of target or higher spKt/V values did not result in appropriate growth in these children, questioning the value of spKt/V as a measure of HD adequacy in children. Provided ranges of outpatient HD prescription can help clinicians and researchers in personalizing and optimizing delivery of dialysis treatment.

Short, frequent, 5-days-per-week, in-center hemodialysis versus 3-days-per week treatment: a randomized crossover pilot trial through the Midwest Pediatric Nephrology Consortium

BACKGROUND

No controlled trials in children with end-stage kidney disease have assessed the benefits of more frequently administered hemodialysis (HD).

METHODS

We conducted a multicenter, crossover pilot trial to determine if short, more frequent (5 days per week) in-center HD was feasible and associated with improvements in blood pressure compared with three conventional HD treatments per week. Because adult studies have not controlled for the weekly duration of dialysis, we fixed the total treatment time at 12 h a week of dialysis during two 3-month study periods; only frequency varied from 5 to 3 days per week between study periods.

RESULTS

Eight children (median age 16.7 years) consented at three children's hospitals. The prespecified primary composite outcome was a sustained 10% decrease in systolic blood pressure and/or a decrease in antihypertensive medications relative to each study period's baseline. Among the six patients completing both study periods, five (83.3%) experienced the primary outcome during HD performed 5 days per week but not 3 days per week; one of the six (16.7%) achieved that outcome during 3-day but not 5-day (p = 0.22) per week HD. During 5-day HD, all patients had significantly more treatments during which their pre-HD systolic (p = 0.01) or diastolic (p = 0.01) blood pressure was 10% lower than baseline.

CONCLUSIONS

We observed that more frequent HD sessions per week was feasible and associated with improved blood pressure control, but barriers to changing thrice-weekly standard of care include financial reimbursement and the time demands associated with more frequent treatments.

Relationship between Interdialytic Weight Gain and Blood Pressure in Pediatric Patients on Chronic Hemodialysis

Overhydration is reported to be the main cause of hypertension (HTN) as well as to have no association with HTN in hemodialysis (HD) population. This is the first report of the relationship between interdialytic weight gain (IDWG) and pre-HD blood pressure (BP) in pediatric patients in relation to residual urine output (RUO). We studied 170 HD sessions and interdialytic periods performed during a 12-week period in 5 patients [age 4–17 years, weight 20.8–66 kg, 3 anuric (102 HD sessions), and 2 nonanuric (68 HD sessions)]. BP is presented as systolic BP index (SBPI) and diastolic BP index (DBPI), calculated as systolic or diastolic BP/95th percentile for age, height, and gender. IDWG did not differ (P > 0.05) between anuric and nonanuric pts. There was a positive but not significant correlation between IDWG and both pre-HD SBPI (r = 0.833, P = 0.080) and pre-HD DBPI (r = 0.841, P = 0.074). Pre-HD SBPI (1.01 ± 0.12 versus 1.13 ± 0.18) and DBPI (0.92 ± 0.16 versus 1.01 ± 0.24) were higher in nonanuric patents (P < 0.001 and P < 0.01, resp.). Pre-HD HTN may not be solely related to IDWG and therapies beyond fluid removal may be needed. Individualized approach to HTN management is necessary in pediatric dialysis population.

Finding covert fluid: methods for detecting volume overload in children on dialysis

BACKGROUND

Lung ultrasound is a novel technique for detecting generalized fluid overload in children and adults with end-stage renal disease (ESRD). Echocardiography and bioimpedance spectroscopy are established methods, albeit variably adopted in clinical practice. We compared the practicality and accuracy of lung ultrasound with current objective techniques for detecting fluid overload in children with ESRD.

METHODS

A prospective observational study was performed to compare lung ultrasound B-lines, echocardiographic measurement of inferior vena cava parameters and bioimpedance spectroscopy in the assessment of fluid overload in children with ESRD on dialysis. The utility of each technique in predicting fluid overload, based on short-term weight gain, was assessed. Multiple linear regression models to predict fluid overload by weight were explored.

RESULTS

A total of 22 fluid assessments were performed in 13 children (8 on peritoneal dialysis, 5 on haemodialysis) with a median age of 4.0 (range 0.8-14.0) years. A significant linear correlation was observed between the number of B-lines detected by lung ultrasound and fluid overload by weight (r = 0.57, p = 0.005). A non-significant positive linear correlation was observed between fluid overload by weight and bioimpedance spectroscopy (r = 0.43, p = 0.2), systolic blood pressure (r = 0.19, p = 0.4) and physical examination measurements (r = 0.19, p = 0.4), while a non-significant negative linear relationship was found between the inferior vena cava collapsibility index and fluid overload by weight (r = -0.24, p = 0.3). In multiple linear regression models, a combination of three fluid parameters, namely lung ultrasound B-lines, clinical examination and systolic blood pressure, best predicted fluid overload (R ²  = 0.46, p = 0.05).

CONCLUSIONS

Lung ultrasound may be superior to echocardiographic methods and bioimpedance spectroscopy in detecting volume overload in children with ESRD. Given the practicality and sensitivity of this new technique, it can be adopted alongside clinical examination and blood pressure in the routine assessment of fluid status in children with ESRD.

Effect of the decrease in dialysate sodium in pediatric patients on chronic hemodialysis

Optimal dialysate sodium (dNa) is unknown, with both higher and lower values suggested in adult studies to improve outcomes. Similar studies in pediatric hemodialysis (HD) population are missing. This is the first report of the effect of two constant dNa concentrations in pediatric patients on chronic HD. 480 standard HD sessions and interdialytic periods were studied in 5 patients (age 4-17 years, weight 20.8-66 kg) during a period of 6-11 months per patient. dNa was 140 mEq/L during the first half, and 138 mEq/L during the second half of the study period for each patient. Lowering dNa was associated with improved preHD hypertension, decreased interdialytic weight gain, decreased need for ultrafiltration, lower sodium gradient and was well tolerated despite lack of concordance with predialysis sNa, that was variable. Further studies are needed to verify our findings and to investigate if an even lower dNa may be more beneficial in the pediatric HD population.