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Impaired baroreflex sensitivity (BRS) is partially responsible for erratic blood pressure fluctuations in End-Stage Renal Disease (ESRD) patients on chronic hemodialysis (HD), which is related to autonomic nervous dysfunction. The sequence method with delayed signals allows for the measurement of BRS in a non-invasive fashion and the investigation of alterations in this physiological feedback system that maintains BP within healthy limits. Our objective was to evaluate the modified delayed signals in the sequence method for BRS assessment in ESRD patients without pharmacological antihypertensive treatment and compare them with those of healthy subjects. We recruited 22 healthy volunteers and 18 patients with ESRD. We recorded continuous BP to obtain a 15-min time series of systolic blood pressure and interbeat intervals during the supine position (SP) and active standing (AS) position. The time series with delays from 0 to 5 heartbeats were used to calculate the BRS, number of data points, number of sequences, and estimation error. The BRS from the ESRD patients was smaller than in healthy subjects (p < 0.05). The BRS estimation with the delayed sequences also increased the number of data points and sequences and decreased the estimation error compared to the original time series. The modified sequence method with delayed signals may be useful for the measurement of baroreflex sensitivity in ESRD patients with a shorter recording time and maintaining an estimation error below 0.01 in both the supine and active standing positions. With this framework, it was corroborated that baroreflex sensitivity in ESRD is decreased when compared with healthy subjects.

Exploring the presence of nonlinearity through surrogate data testing provides insights into the nature of physical and biological systems like those obtained from heart rate variability (HRV). Short-term HRV time series are of great clinical interest to study autonomic impairments manifested in chronic diseases such as the end stage renal disease (ESRD) and the response of patients to treatment with hemodialysis (HD). In contrast to Iterative Amplitude Adjusted Fourier Transform (IAAFT), the Pinned Wavelet Iterative Amplitude Adjusted Fourier Transform (PWIAAFT) surrogates preserve nonstationary behavior in time series, a common characteristic of HRV. We aimed to test synthetic data and HRV time series for the existence of nonlinearity. Recurrence Quantitative Analysis (RQA) indices were used as discriminative statistics in IAAFT and PWIAAFT surrogates of linear stationary and nonstationary processes. HRV time series of healthy subjects and 29 ESRD patients before and after HD were tested in this setting during an active standing test. Contrary to PWIAAFT, linear nonstationary time series may be erroneously regarded as nonlinear according to the IAAFT surrogates. Here, a lower proportion of HRV time series was classified as nonlinear with PWIAAFT, compared to IAAFT, confirming that the nonstationarity condition influences the testing of nonlinear behavior in HRV. A contribution of nonlinearity was found in the HRV data of healthy individuals. A lower proportion of nonlinear time series was also found in ESRD patients, but statistical significance was not found. Although this proportion tends to be lower in ESRD patients, as much as 60% of time series proved to be nonlinear in healthy subjects. Given the important contribution of nonlinearity in HRV data, a nonlinear point of view is required to achieve a broader understanding of cardiovascular physiology.

Simple Summary An increase in intraocular pressure during chronic hemodialysis is linked to ocular complications, such as glaucoma. The behavior of intraocular pressure during hemodiafiltration is unknown. Changes in intraocular pressure with a sodium dialysate concentration fixed at 138 mmol/L and an individualized concentration were studied in 13 patients with end-stage renal disease treated with hemodiafiltration. Up to 31% patients presented an episode of intraocular hypertension without differences between sodium profiles. A large variability in intraocular pressure within patients and a high prevalence of transient intraocular hypertension were found. Abstract Ocular complications are common among end-stage renal disease patients and some complications had been linked to increments of intraocular pressure (IOP) during hemodialysis. The changes of IOP during hemodiafiltration (HDF) have been scarcely investigated and the potential influence of the sodium dialysate concentration is unknown. The aim of this study was to compare the IOP changes during HDF with sodium dialysate concentration, either fixed or individualized. Thirteen end-stage renal disease patients participated in the study; they were treated with HDF using a dialysate sodium profile fixed at 138 mmol and another session with an individualized sodium profile. The intraocular pressure was measured before and after each session and every 30 min during HDF. Both groups had a similar HDF prescription, blood pressure, and biochemical parameters. At the end of hemodiafiltration, sodium concentration decreased only in the fixed sodium profile group. The number of patients with at least an episode of intraocular hypertension during HDF ranged from 5 (19%) to 8 (31%) without significant differences between right and left eye nor between dialysate sodium concentration. During HDF, there is a large variability of IOP; transient events of intraocular hypertension are highly prevalent in this sample, and they are not related to the sodium dialysate concentration.

Depression and anxiety are highly prevalent psychological disorders in end-stage renal disease (ESRD) that have a negative clinical impact. The purpose of our study was to identify factors associated with the presence of depression and anxiety, in a sample of ESRD patients treated with hemodialysis. We included 187 patients from two dialysis facilities, age 18–65 years. Beck’s depression and anxiety inventories, KDQOL36 questionnaire, the cognitive distortion scale and the Mexican scale of resilience were used. Socio-demographic and clinical information was obtained from medical records. Depression was present in 143 (76.4%) patients. Patient with depression were older (33 (26–52) years vs. 30 (24.43) years, p = 0.025), had a lower education level (36% vs. 9%, p = 0.001), used more medications (67% vs. 36%, p = 0.001), had a comorbidity (75% vs. 41%, p = 0.001), and a higher proportion were waiting for a kidney transplant. Anxiety was present in 112 (59.8%) cases. By multivariate analysis, depression was independently associated with lower education, absence of previous kidney transplant, anxiety, higher cognitive distortion, lower psychological resilience, and lower quality of life scores. In conclusion, lower psychological resilience, lower education level, and higher cognitive distortions are factors associated with depression and anxiety in ESRD patients.

Gender and sex differences affect women with kidney failure (KF) negatively at all stages of the disease. This study assessed gender differences in self-care, hemodialysis symptoms, and quality of life in a sample of 102 adult KF patients treated with hemodialysis, from two clinical centers in Mexico. Self-care agency, quality of life, and the symptoms related to hemodialysis were evaluated through questionnaires, and sociodemographic and laboratory variables were obtained from the clinical records. Compared to male patients, female patients reported similar self-care, lower quality of life subscales (symptoms, physical functioning, pain, and overall health), and higher prevalence and intensity of hemodialysis symptoms. There were gender differences regarding the correlation between self-care and quality of life, symptoms intensity, and symptoms prevalence. In conclusion, women with KF treated with hemodialysis perceived a higher impact of hemodialysis and reported a lower quality of life than men. Despite having a similar self-care agency, the self-care correlations with quality of life and hemodialysis symptoms appeared different between men and women treated with chronic hemodialysis. Such differences may be important in future nursing interventions to improve self-care and quality of life among KF patients.

espanolLa resiliencia consiste en una serie de habilidades personalizadas que sirven para afrontar situaciones adversas y superarlas, e incluso salir fortalecido. La resiliencia en pacientes con insuficiencia renal cronica (IRC) tratados con hemodialisis (HD) se ha evaluado con cuestionarios generales, no especificos para esta poblacion. Objetivo Evaluar las propiedades psicometricas de un cuestionario de resiliencia en pacientes tratados con HD cronica. Metodo Se incluyeron 280 pacientes con IRC (edad 18 a 85 anos, 44% mujeres) tratados con HD al menos dos meses en seis unidades de hemodialisis en Mexico, que respondieron los inventarios de depresion y ansiedad de Beck, un inventario de distorsiones cognitivas y la escala de medicion de resiliencia con mexicanos (RESI-M). Resultados Por duplicidad en mas de un factor, se eliminaron dos de 43 reactivos en el analisis factorial exploratorio. Se confirmaron cinco factores que explicaron 63.4% de la varianza total, con alfa de Cronbach de .96 (el alfa en los cinco factores va de .85 a .95). El analisis confirmatorio mostro un modelo estructural teorico que se ajusta aceptable, equilibrada y parsimoniosamente a los datos empiricos. Los cinco factores se correlacionan positivamente entre ellos y negativamente con los sintomas de ansiedad, depresion y los pensamientos distorsionados. Discusion y conclusion La escala RESI-M es valida y confiable para evaluar resiliencia en pacientes tratados con HD cronica. Los factores de resiliencia evaluados con la RESI-M son un blanco terapeutico potencial para disminuir los sintomas depresivos y ansiosos en estos pacientes. EnglishIntroduction: resilience consists of a series personalized skills to cope with adverse situations and overcome them, and even emerge strengthened. Resilience in patients with chronic renal insufficiency (CRI) treated with hemodialysis (HD) has been evaluated with general questionnaires that are not specific for this population. Objective: to evaluate the psychometric properties of a resilience questionnaire in patients treated with chronic HD. Method: the study included 280 patients with CRI (aged 18 to 85, 44% women) treated with HD for at least two months in six hemodialysis units in Mexico, who completed Beck’s depression and anxiety inventories, an inventory of cognitive distortions, and the Mexican Resilience Measurement Scale (RESI-M). Results: owing to the duplication of more than one factor, two of the 43 items were eliminated in the exploratory factor analysis. We confirmed five factors that explained 63.4% of the total variance, with a Cronbach’s alpha of .96 (the alpha ranges in the five factors from .85 to .95). The confirmatory analysis showed a theoretical structural model that fits the empirical data in an acceptable, balanced, and parsimonious way. The five factors correlate positively with each other and negatively with anxiety and depression symptoms and distorted thoughts. Discussion and conclusion: the RESI-M scale is valid and reliable for assessing resilience in patients treated with chronic HD. Resilience factors evaluated with RESI-M are a potential therapeutic target to reduce depression and anxiety symptoms in these patients.

Se trata de hombre de 28 años de edad conocido previamente sano. Inició su cuadro con presencia de náuseas, vómitos y ataque al estado general. Durante la valoración se documentó nitrógeno ureico en sangre (BUN) 142 mg/dl y creatinina 12.8 mg/dl. Por recursos económicos limitados no fue posible inicio inmediato de terapia dialítica y solo se inició manejo médico. Tras progresión de la sintomatología, se inició terapia dialítica 10 meses después, recibiendo solamente dos sesiones por semana.

Cardiovascular regulatory mechanisms that fail to compensate for ultrafiltration and cause hypovolemia during hemodialysis (HD) are not completely understood. This includes the interaction between the autonomic nervous system and the biochemistry that regulates blood pressure and modulates cardiac activity and vascular tone in response to hypovolemia in patients treated with HD. The objective was to evaluate the association of spectral indices of heart rate variability (HRV) with serum levels of angiotensin II, angiotensin 1–7, nitric oxide and total antioxidant capacity during HD. Electrocardiographic records were obtained from 20 patients during HD (3 h), from which HRV data and spectral power data in the very-low-frequency (VLF), low-frequency (LF) and high-frequency (HF) bands were generated. Three blood samples per patient were collected during HD (0.0, 1.5, 3.0 h) to determine the levels of biomarkers involved in the pressor response during HD. Angiotensin II had a positive correlation with VLF (r = 0.390) and with LF/HF (r = 0.359) and a negative correlation with LF (r = −0.262) and HF (r = −0.383). There were no significant correlations between HRV and the other biomarkers. These results suggest that during HD, VLF could reflect the serum levels of angiotensin II, which may be associated with the autonomic response to HD.

Intradialytic hypotension occurs in 10&ndash, 30% of hemodialysis (HD) sessions. This phenomenon affects the cardiovascular system&rsquo, s functions, which are reflected in the activity of the autonomic nervous system (ANS). To indirectly assess the ANS during HD, we analyzed the mean R&ndash, R intervals and the spectral power of heart rate variability (HRV) from 20 end-stage renal disease patients divided into hypotensive and non-hypotensive groups. The spectrotemporal analysis was accomplished using short-time Fourier transform with 10 min epochs of HRV overlapping by 40%. The spectral power was divided into three segments according to high frequency, low frequency, and very low frequency bandwidths and averaged to fit quadratic regression models. The analysis of the mean R&ndash, R intervals showed significant differences between the groups (p = 0.029). The power variation over time was significant in each spectral band (p ≪ 0.05). The average power, maximum power, and time when the peak was reached differed for each band and between groups, showing the ability to correctly identify the decompensation of the ANS and discriminate between hypotensive and non-hypotensive patients. Additionally, the changes in the sympathovagal ratio were not significant and very scattered for the hypotensive group (p = 0.23) compared to the non-hypotensive group, where the changes were significant (p ≪ 0.05) and much less scattered.

The aim of this study was to evaluate the intraocular pressure during hemodialysis and hemodiafiltration. Fifteen patients were enrolled (seven treated with hemodialysis therapy and eight with hemodiafiltration). The intraocular pressure was measured before and after dialysis and every 30 min during dialysis. Before dialysis, both groups had similar dialysis prescription, blood pressure, and biochemical parameters. At the end of dialysis, potassium, and osmolarity decreased in both groups, while systolic blood pressure and sodium decreased in the hemodialysis group, and glucose decreased in the hemodiafiltration group. Mean intraocular pressure was similar between groups at all measured times and had no significant changes during hemodialysis. During minute 120 of hemodiafiltration, mean intraocular pressure in the left eye decreased significantly compared to minute 90. This suggests a high intra-individual variability of intraocular pressure during both types of dialysis, which could be relevant particularly among those with the risk of glaucoma.

The aim of this work was to evaluate the short-term fractal index (α1 ) of heart rate variability (HRV) in chronic renal failure (CRF) patients by identifying the effects of orthostatism and hemodialysis (HD), and by evaluating the correlation between α1 and the mean RR interval from sinus beats (meanNN). HRV time series were derived from ECG data of 19 CRF patients and 20 age-matched healthy subjects obtained at supine and orthostatic positions (lasting 5 min each). Data from CRF patients were collected before and after HD. α1 was calculated from each time series and compared by analysis of variance. Pearson's correlations between meanNN and α1 were calculated using the data from both positions by considering three groups: healthy subjects, CRF before HD and CRF after HD. At supine position, α1 of CRF patients after HD (1.17 ± 0.30) was larger (P

The assessment of spontaneous variability of blood pressure and heart rate is based on specific physiological hypotheses about dynamic features, for example, the baroreflex modulation of heart rate over time in daily life. Usually, arterial baroreflex control of heart rate is explored without delays between blood pressure and heart rate data points, within a narrow range of values, excluding the analysis of saturation regions or low-threshold changes. In this work, we examine the dynamic interactions between systolic blood pressure (SBP) and interbeat interval (IBI), in 15-min length time series and for the first time using the analysis of diagonals derived from a cross-recurrence plots in healthy persons and end-stage renal disease (ESRD) patients. We found that ESRD patients have stronger intermittent dynamical interactions between IBI and SBP, but they lose most of the dynamical interactions. Although healthy subjects exhibit a continuously changing order of precedence between IBI and SBP at different lags, ESRD patients preserve this changing order of precedence only for lags >0 beats. NEW & NOTEWORTHY This study is the first to compare the time-variant pattern of systolic blood pressure (SBP) and interbeat interval (IBI) coupling between ESRD patients and healthy volunteers through the analysis of diagonal in cross-recurrence plots, and in the face of an orthostatic challenge. Our results demonstrated alternant interactions on the order of precedence (IBI → SBP or SBP→ IBI) at different time delays. This pattern is different in resting position and during active standing for the two groups studied, and interestingly, some association patterns are lost in ESRD patients. These patterns of alternant interactions on the order of precedence could be related to autonomic neural activities and cardiovascular synchronization at different scales both in time and space. This could reflect physiological adaptive flexibility of cardiovascular regulation. Losing some association patterns in ESRD may be the result of chronic adjustments of many physiological mechanisms (including chronic sympathetic hyperactivity), which could increase cardiovascular vulnerability to hemodynamic challenges.

Heart rate variability (HRV) has been used to indirectly assess and study the autonomic nervous system (ANS). For the analysis of HRV, two different time windows are recommended.

Introduction: Patients in hemodiafiltration (HDF) eliminate volume overload by ultrafiltration. Vascular volume loss is among the main mechanisms contributing to adverse events such as intradialytic hypotension. Here, we hypothesize that the intradialytic exercise (IDEX) is an intervention that could improve the acute response of physiological mechanisms involved during vascular volume loss. To test this hypothesis, we evaluated the hemodynamic response to mild aerobic exercise during HDF. Methods: Nineteen end-stage renal disease (ESRD) patients (11 women: 40 ± 10.8 years old, and 8 men: 42 ± 21 years old) receiving HDF thrice a week, with 6 months of previous physical conditioning, participated in this study. Three HDF sessions were scheduled for each patient: 1 resting in supine position, 1 resting in sitting position, and 1 doing aerobic exercise. The first 2 sessions were taken as control. The ultrafiltration rate was set to 800 mL/h in each session. The hemodynamic response was monitored through the relative blood volume (RBV), and cardiovascular variables measured noninvasively by photoplethysmography. Adequacy variables such as Kt/V and percentage reduction of urate, urea, creatinine (Cr), and phosphate were also monitored. Findings: The decrease rate of the RBV was smaller in the session with IDEX compared to the sessions with no exercise. No differences were found neither in the cardiovascular variables nor in the adequacy variables among the 3 sessions. There were no hypotension events during the session with exercise, and 8 events during the sessions without exercise (p = 0.002). Discussion: Mild exercise during HDF decreased the RBV drop and was associated with less hypotension events. The lack of differences in the hemodynamic variables suggests an adequate acute response of cardiovascular compensation variables to intradialytic hypovolemia.

Despite having good intentions, hemodialysis (HD) clinics often fail to sustain exercise programs that they initiate. There are many reasons for this, including a lack of funding, inadequate training of the clinic staff, a lack of exercise professionals to manage the program or train the staff, and the many challenges inherent to exercising a patient population with multiple comorbid diseases. Despite these barriers, there are several outstanding examples of successful exercise programs in HD clinics throughout the world. The aim of this manuscript is to review the characteristics of four successfully sustained HD exercise programs in Portugal, Canada, Mexico, and Germany. We describe the unique approaches they have used to fund and manage their programs, the varied exercise prescriptions they incorporate, the unique challenges they face, and discuss the benefits they have seen. While the programs differ in many regards, a consistent theme is that they each have substantial and committed support from the entire clinic staff, including the nephrologists, administration, nurses, dietitians, and technicians. This suggests that exercise programs in HD clinics can be successfully implemented and sustained provided significant effort is made to foster a culture of physical activity throughout the clinic. info:eu-repo/semantics/publishedVersion

Power spectral analysis of heart rate variability (HRV) offers a possibility to non-invasively quantify autonomic cardiac regulation. The technique splits the spectrum of the HRV into high frequency (HF), low frequency (LF) and very-low frequency (VLF) bands, and relates their power content to parasympathetic outflow, sympathetic outflow, and hormonal factors as well as thermoregulation, respectively. In this work, we applied this technique on HRV data from 20 end-stage renal disease (ESRD) patients to estimate power distribution in these three bands as well as their changes respect to time during hemodiafiltration (HDF) therapy; as an indirect way to assess the modulatory activity over the cardiac system. HRV data was processed using the continuous wavelet transform (CWT), power was estimated using 5-min as well as 10-min epochs for comparison purposes, and the results were normalized to unity before linear regression analysis. For 5-min epochs, the LF power increased (p = 0.035), while there were no significant changes in the HF power (p = 0.2). In contrast, for 10-min epochs, both the LF (p = 0.002) and HF (p = 0.043) power decreased, while the VLF power increased (p

The aim of this study was to evaluate the intraocular pressure during hemodialysis and hemodiafiltration. Fifteen patients were enrolled (seven treated with hemodialysis therapy and eight with hemodiafiltration). The intraocular pressure was measured before and after dialysis and every 30 min during dialysis. Before dialysis, both groups had similar dialysis prescription, blood pressure, and biochemical parameters. At the end of dialysis, potassium, and osmolarity decreased in both groups, while systolic blood pressure and sodium decreased in the hemodialysis group, and glucose decreased in the hemodiafiltration group. Mean intraocular pressure was similar between groups at all measured times and had no significant changes during hemodialysis. During minute 120 of hemodiafiltration, mean intraocular pressure in the left eye decreased significantly compared to minute 90. This suggests a high intra-individual variability of intraocular pressure during both types of dialysis, which could be relevant particularly among those with the risk of glaucoma.

Hemodialysis (HD) is usually performed with the gradually decreasing ultrafiltration rate (UFR) profile (dUFR). The aim of the present study was to compare the hemodynamic response to HD with the dUFR to that of HD with the gradually increasing UFR profile (iUFR). The study population included 10 patients (three women, mean age: 28 ± 8 years) undergoing maintenance HD who had reached dry weight without taking antihypertensive medications. Each patient received (in random order) one HD session with the dUFR and another with the iUFR (both with 3 h total UFR = 2200 mL). Hemodynamic response was evaluated with a brachial blood pressure (BP) monitor, echocardiogram and Portapres to measure digital BP, heart rate, cardiac output, stroke volume, and peripheral resistance. Mean values were compared at each HD hour during the first 3 h of a 4-h HD session. The HD characteristics, including Kt/V, were similar for both UFR profiles. Relative blood volume decreased more gradually and linearly with the iUFR. Hemodynamic variables were not significantly different between the two profiles, but brachial BP was more stable with the iUFR. Digital diastolic BP increased with both profiles. Peripheral resistance increased with both profiles, and tended to increase more with the iUFR. Echocardiographic variables changed similarly during the HD session with both profiles. In conclusion, these two UFR profiles are similar in most hemodynamic variables. The statistical equivalence of both profiles suggests that either could be prescribed based on the clinical characteristics of the patient.

The scaling properties of heart rate variability data are reliable dynamical features to predict mortality and for the assessment of cardiovascular risk. The aim of this manuscript was to determine if the scaling properties, as provided by the sign and magnitude analysis, can be used to differentiate between pathological changes and those adaptations basically introduced by modifications of the mean heart rate in distinct manoeuvres (active standing or hemodialysis treatment, HD), as well as clinical conditions (end stage renal disease, ESRD). We found that in response to active standing, the short-term scaling index (α1) increased in healthy subjects and in ESRD patients only after HD. The sign short-term scaling exponent (α1sign) increased in healthy subjects and ESRD patients, showing a less anticorrelated behavior in active standing. Both α1 and α1sign did show covariance with the mean heart rate in healthy subjects, while in ESRD patients, this covariance was observed only after HD. A reliable estimation of the magnitude short-term scaling exponent (α1magn) required the analysis of time series with a large number of samples (>3000 data points). This exponent was similar for both groups and conditions and did not show covariance with the mean heart rate. A surrogate analysis confirmed the presence of multifractal properties (α1magn > 0.5) in the time series of healthy subjects and ESDR patients. In conclusion, α1 and α1sign provided insights into the physiological adaptations during active standing, which revealed a transitory impairment before HD in ESRD patients. The presence of multifractal properties indicated that a reduced short-term variability does not necessarily imply a declined regulatory complexity in these patients.

Linear heart rate variability (HRV) indices are dependent on the mean heart rate, which has been demonstrated in different models (from sinoatrial cells to humans). The association between nonlinear HRV indices, including those provided by recurrence plot quantitative analysis (RQA), and the mean heart rate (or the mean cardiac period, also called meanNN) has been scarcely studied. For this purpose, we analyzed RQA indices of five minute-long HRV time series obtained in the supine position and during active standing from 30 healthy subjects and 29 end-stage renal disease (ESRD) patients (before and after hemodialysis). In the supine position, ESRD patients showed shorter meanNN (i.e., faster heart rate) and decreased variability compared to healthy subjects. The healthy subjects responded to active standing by shortening the meanNN and decreasing HRV indices to reach similar values of ESRD patients. Bivariate correlations between all RQA indices and meanNN were significant in healthy subjects and ESRD after hemodialysis and for most RQA indices in ESRD patients before hemodialysis. Multiple linear regression analyses showed that RQA indices were also dependent on the position and the ESRD condition. Then, future studies should consider the association among RQA indices, meanNN, and these other factors for a correct interpretation of HRV.

The aim of this work was to measure the impact of active orthostatism and hemodialysis (HD) upon heart rate variability (HRV) in chronic renal failure (CRF) patients before and after HD. Nineteen healthy subjects (age 27 ± 8 years old, 13 were female) and 19 unmedicated CRF patients with HD thrice per week (average HD vintage = 12 months, age 32 ± 9 years old, 11 were female) were included. Five-minute length HRV time series were obtained during supine position and orthostatism. Recordings from CRF patients were obtained before and after HD. Time domain and frequency domain HRV indexes were compared by analysis of variance. The correlation between each HRV index and change in sympathetic weighting induced by different maneuvers was tested by Kendall’s Tau correlation. A p value

The aim of this study was to evaluate the factors that prevent dry weight achievement in patients with end-stage renal disease (ESRD) in renal replacement therapy through the change in their body weight after kidney transplant (KT) compared with 1 week before KT. The study included 188 ESRD patients of diverse etiology who received living kidney transplantation with normal immediate graft function, 62.2% were male, age 29 ± 11 years old. All patients were on renal replacement therapy for at least 1 month before KT with either hemodiafiltration (N = 106), hemodialysis (N = 25), or peritoneal dialysis (N = 57). Based on body weight difference (after transplant-before transplant), patients with body weight difference ≤2 kg were considered as being close to their dry weight (Group 1, N = 112), whereas patients with body weight difference >2 kg were considered as being overhydrated (Group 2, N = 76). Clinical and biochemical characteristics were obtained from the medical records at three periods of time: time of ESRD initiation (baseline), 1 week before undergoing KT, and 1 week after KT. The mean time (± standard deviation) from renal replacement therapy initiation to the week before KT was 9.2 ± 5 months. Group 2 had a higher proportion of men, antihypertensive use, peritoneal dialysis, and higher urine output during all periods. Before KT, Group 2 had higher systolic and diastolic blood pressures than Group 1. After KT, both systolic and diastolic blood pressures decreased in Group 2, whereas no change occurred in Group 1. Before KT, Group 2 had higher levels of blood urea nitrogen, creatinine, uric acid, and phosphorous compared with Group 1. Compared with baseline, Group 1 had more optimal blood urea nitrogen, creatinine, and uric acid parameters before KT than Group 2. After KT, all parameters improved with respect to baseline in both groups. Hemoglobin, albumin, and sodium were similar between groups, except for higher hemoglobin in Group 2 than Group 1 after KT. Multivariate regression analysis showed that male sex, peritoneal dialysis, and systolic blood pressure before KT were independent risk factors for overhydration. In conclusion, high systolic blood pressure and peritoneal dialysis were two independent modifiable variables associated with overhydration before KT. Assessment of the body weight change after KT is a useful tool to evaluate dry weight, in addition to identifying variables associated with poor volume control. This could allow adjustment of clinical and dialysis parameters in future patients.

The aim of this work was to evaluate the short-term fractal index (α

This study evaluated the usefulness of the three-dimensional representation of electrocardiogram traces (3DECG) to reveal acute and gradual changes during a full session of hemodiafiltration (HDF) in end-stage renal disease (ESRD) patients. Fifteen ESRD patients were included (six men, nine women, age 46 ± 19 years old). Serum electrolytes, blood pressure, heart rate, and blood urea nitrogen (BUN) were measured before and after HDF. Continuous electrocardiograms (ECGs) obtained by Holter monitoring during HDF were used to produce the 3DECG. Several major disturbances were identified by 3DECG images: increase in QRS amplitude (47%), decrease in T-wave amplitude (33%), increase in heart rate (33%), and occurrence of arrhythmia (53%). Different arrhythmia types were often concurrent and included isolated supraventricular premature beats (N = 5), atrial fibrillation or atrial bigeminy (N = 2), and isolated premature ventricular beats (N = 6). Patients with decrease in T-wave amplitude had higher potassium and BUN (both before HDF and total removal) than those without decrease in T-wave amplitude (P

Hemodialysis (HD) is usually performed with the gradually decreasing ultrafiltration rate (UFR) profile (dUFR). The aim of the present study was to compare the hemodynamic response to HD with the dUFR to that of HD with the gradually increasing UFR profile (iUFR). The study population included 10 patients (three women, mean age: 28 ± 8 years) undergoing maintenance HD who had reached dry weight without taking antihypertensive medications. Each patient received (in random order) one HD session with the dUFR and another with the iUFR (both with 3 h total UFR = 2200 mL). Hemodynamic response was evaluated with a brachial blood pressure (BP) monitor, echocardiogram and Portapres to measure digital BP, heart rate, cardiac output, stroke volume, and peripheral resistance. Mean values were compared at each HD hour during the first 3 h of a 4-h HD session. The HD characteristics, including Kt/V, were similar for both UFR profiles. Relative blood volume decreased more gradually and linearly with the iUFR. Hemodynamic variables were not significantly different between the two profiles, but brachial BP was more stable with the iUFR. Digital diastolic BP increased with both profiles. Peripheral resistance increased with both profiles, and tended to increase more with the iUFR. Echocardiographic variables changed similarly during the HD session with both profiles. In conclusion, these two UFR profiles are similar in most hemodynamic variables. The statistical equivalence of both profiles suggests that either could be prescribed based on the clinical characteristics of the patient.

The aim of this study was to analyze the behavior of the autonomous nervous system (ANS) using heart rate variability in a hemodynamic stable patients group, during hemodialysis (HD), two different ultrafiltration profiles, the first gradual increasing ultrafiltration rate (UF1) and the other gradually decreasing ultrafiltration rate (UF2). In nine patients haemodinamically stables (28 ± 8 years), we take EKG in lead II simultaneously HD, during three hours, the signal was process to obtain the tachogram and using the Welch method for spectral analysis. Results showed that all cases presented greater power in the Low frequencies (LF) band compared to the power in High frequencies (HF) band, this result was consistent with the activation of Sympathetic Nervous System (SNS) in response to the proper function of the baroreceptor regulation. Using a power spectral density to analyses, no differences was found between average values of LF/HF balance, using a UF1 (4.19 ± 1.7553) or UF2 (4.92 ± 2.9953) (p = 0.5407) in this group. Ultrafiltration profile was indifferent for this haemodinamically stable patients group.

Objectives Psychological treatment of depression in end-stage renal disease (ESRD) has focused on severely depressed patients. We designed and tested a brief (5 weeks) cognitive behavioural intervention (CBI) to reduce mild and moderate depression and anxiety symptoms in patients with ESRD. Design For the purpose of this study, a single-blind, randomized controlled design was used to compare patients with ESRD under haemodialysis treatment with and without the CBI. Methods Depression and anxiety symptoms were screened in 152 subjects (18–60 years old, 84 male). Sixty participants (age 41.8 ± 14.7, 29 males) with mild or moderate scores of depression (Beck Depression Inventory) and anxiety (Beck Anxiety Inventory) were randomly assigned to CBI or the control group. CBI techniques consisted of positive self-reinforcement, deep breathing, muscle relaxation, and cognitive restructuring. Depression, anxiety, quality of life (QoL), and cognitive distortion scores were evaluated at baseline, after 5 weeks (end of treatment) and after 4-week follow-up. All scores were compared by ANOVA for repeated measures with post-hoc tests adjusted by Bonferroni's method (p

Kidney transplant (KT) resolves many of the cardiac abnormalities associated with chronic kidney failure (CKF). This study analyzed cardiac alterations of kidney failure and their modification with transplant. Thirteen patients in CKF underwent conventional echocardiograms, dobutamine stress echocardiograms, and injection of contrast to examine perfusion before KT and 3 months after transplant. Nine patients had evidence of left ventricular hypertrophy and six had evidence of diastolic dysfunction. Wall thickness, left ventricular mass, and mass index diminished after KT; only two patients continued to manifest hypertrophy. Left ventricular systolic diameters and volumes diminished at 3 months, and diastolic diameters after 4 months. Left ventricular fractional shortening and ejection fraction increased 3 months after transplant. At the end of the study, only two patients continued to show diastolic dysfunction. Dobutamine echocardiograms showed no segmental wall-movement abnormalities. Myocardial perfusion was normal before and after transplant. The results suggest that KT diminishes hypertrophy and improves left ventricular systolic and diastolic function. Echocardiography provides valuable information for detection and follow-up of cardiac abnormalities in patients with kidney disease. Evaluation of segmental wall movement and myocardial perfusion aid in demonstrating that our studied patients with CKF had no indirect signs of coronary artery disease.

The aim of the study was to analyze the behavior of the autonomous nervous system (ANS) during hemodialysis (HD) treatment with two ultrafiltration (UF) profiles: gradually decreasing UF rate and gradually decreasing UF rate. Spectral analysis of heart rate variability (HRV) was used to estimate the mean power in the low frequency (LF) band and the high frequency (HF) band indexes. LF was larger than HF in all patients, which is consistent with a sympathetic nervous system activation response during HD. Although each patient responded differently to each UF profile, the mean values of all indexes from the whole group were similar between the two UF profiles.

The aim of this study was to evaluate the factors that prevent dry weight achievement in patients with end-stage renal disease (ESRD) in renal replacement therapy through the change in their body weight after kidney transplant (KT) compared with 1 week before KT. The study included 188 ESRD patients of diverse etiology who received living kidney transplantation with normal immediate graft function, 62.2% were male, age 29 ± 11 years old. All patients were on renal replacement therapy for at least 1 month before KT with either hemodiafiltration (N = 106), hemodialysis (N = 25), or peritoneal dialysis (N = 57). Based on body weight difference (after transplant-before transplant), patients with body weight difference ≤2 kg were considered as being close to their dry weight (Group 1, N = 112), whereas patients with body weight difference2 kg were considered as being overhydrated (Group 2, N = 76). Clinical and biochemical characteristics were obtained from the medical records at three periods of time: time of ESRD initiation (baseline), 1 week before undergoing KT, and 1 week after KT. The mean time (± standard deviation) from renal replacement therapy initiation to the week before KT was 9.2 ± 5 months. Group 2 had a higher proportion of men, antihypertensive use, peritoneal dialysis, and higher urine output during all periods. Before KT, Group 2 had higher systolic and diastolic blood pressures than Group 1. After KT, both systolic and diastolic blood pressures decreased in Group 2, whereas no change occurred in Group 1. Before KT, Group 2 had higher levels of blood urea nitrogen, creatinine, uric acid, and phosphorous compared with Group 1. Compared with baseline, Group 1 had more optimal blood urea nitrogen, creatinine, and uric acid parameters before KT than Group 2. After KT, all parameters improved with respect to baseline in both groups. Hemoglobin, albumin, and sodium were similar between groups, except for higher hemoglobin in Group 2 than Group 1 after KT. Multivariate regression analysis showed that male sex, peritoneal dialysis, and systolic blood pressure before KT were independent risk factors for overhydration. In conclusion, high systolic blood pressure and peritoneal dialysis were two independent modifiable variables associated with overhydration before KT. Assessment of the body weight change after KT is a useful tool to evaluate dry weight, in addition to identifying variables associated with poor volume control. This could allow adjustment of clinical and dialysis parameters in future patients.

Background Hemodiafiltration (HDF), as a convective blood purification technique, has been associated with favorable outcomes improved phosphate control, removal of middle-molecules such as Beta2-microglobulin and the occurrence of intradialytic hypotension (IDH) as compared to diffusive techniques. The aim of this retrospective cohort study in dialysis patients receiving HDF in one urban dialysis facility in Mexico City was to investigate the occurrence of IDH during HDF treatments with varying convective volume prescriptions. Methods Subjects were stratified into equal groups of percentiles of convective volume prescription: Group 1 of 0 to 7.53 liters, group 2 of 7.54 to 14.8 liters, group 3 of 14.9 to 16.96 liters, group 4 of 16.97 to 18.9 liters, group 5 of 21 to 19.9 liters and group 6 of 21.1 to 30 liters. Logistic Regression with and without adjustment for confounding factors was used to evaluate factors associated with the occurrence of IDH. Results 2276 treatments of 154 patients were analyzed. IDH occurred during 239 HDF treatments (10.5% of all treatments). Group 1 showed 31 treatments (8.2%) with IDH whereas group 6 showed IDH in only 15 sessions (4% of all treatments). Odds Ratio of IDH for Group 6 was 0.47 (95% CI 0.25 to 0.88) as compared to Group 1 after adjustment. Conclusions In summary the data of this retrospective cohort study shows an inverse correlation between the occurrence of IDH and convective volume prescription. Further research in prospective settings is needed to confirm these findings.

We studied the response of heart rate variability to hemodialysis and orthostatism using traditional linear indexes and 9 recurrence quantification analysis indexes to reveal changes in the heart rate dynamics. Twenty healthy subjects and 19 chronic renal failure patients treated with hemodialysis thrice a week were included. Five-minute heart rate variability time series were obtained during supine position (clinostatism) and orthostatism from each participant; recordings in renal patients were repeated after hemodialysis. Linear indexes were consistent with sympathetic predominance in response to orthostatism in the control group. Renal patients before hemodialysis showed increased sympathetic predominance in clinostatism, with further increase in orthostatism and hemodialysis. In response to orthostatism, 4 recurrence indexes changed in the control group, while in renal patients any of them changed before hemodialysis and 1 changed after hemodialysis. In clinostatism, renal patients (both before and after hemodialysis) had higher laminarity, trapping time, and recurrence time than the control group. Recurrence indexes showed that the heart rate dynamics in renal patients are different from healthy subjects, suggesting loss of access to some regulatory conditions. These findings are consistent with reports of sympathetic stimulation induced by hemodialysis and active standing.

Late referral of patients with chronic kidney disease (CKD) to specialized care by the nephrologist is associated with worse patient outcomes while on dialysis.To determine the prevalence, risk factors, and consequences of late nephrology referral at a Mexican tertiary care hospital.Retrospective chart review of all adult patients who began chronic hemodialysis between 2002 and 2006 at the National Institute of Cardiology "Ignacio Chavez" (NICICh), Mexico City. Timing of referral to Nephrology Department was classified as early, late or very late if the time elapsed between referral and initiation of dialysis was1 month, between 1-6 months oror = 6 months, respectively. Socio-demographic, clinical, laboratory and echocardiographic characteristics were compared according to timing of referral.Eighty four out of 150 patients were included in the analysis. Of these, 56% were referred1 month, and an additional 15% between 1-6 months prior to the initiation of chronic hemodialysis. In univariate analysis, being referred by a relative or friend was associated with a higher risk (p = 0.04), and being employed with a lower risk of late referral (p = 0.05). Late referred patients were more likely to require emergency dialysis and hospitalization, and of not having a permanent vascular access for their first dialysis. They also had a higher prevalence of severe anemia (hematocrit28%) and of residual kidney function (estimated glomerular filtration rate5 mL/min/1.73 m2), as well as increased left ventricular mass.Late nephrology referral is highly prevalent in our population and is associated with markers of suboptimal predialysis care at the onset of chronic dialysis.

Background In hemodialysis, extracorporeal blood flow (Qb) recommendation is 300–500 mL/min. To achieve the best Qb, we based our prescription on dynamic arterial line pressure (DALP). Methods This prospective study included 72 patients with catheter Group 1 (G1), 1877 treatments and 35 arterio-venous (AV) fistulae Group 2 (G2), 1868 treatments. The dialysis staff was trained to prescribe Qb sufficient to obtain DALP between -200 to -250 mmHg. We measured ionic clearance (IK: mL/min), access recirculation, DALP (mmHg) and Qb (mL/min). Six prescription zones were identified: from an optimal A zone (Qb > 400, DALP -200 to -250) to zones with lower Qb E (Qb < 300, DALP -200 to -250) and F (Qb < 300, DALP > -199). Results Treatments distribution in A was 695 (37%) in G1 vs. 704 (37.7%) in G2 (P = 0.7). In B 150 (8%) in G1 vs. 458 (24.5%) in G2 (P < 0.0001). Recirculation in A was 10.0% (Inter quartile rank, IQR 6.5, 14.2) in G1 vs. 9.8% (IQR 7.5, 14.1) in G2 (P = 0.62). IK in A was 214 ± 34 (G1) vs. 213 ± 35 (G2) (P = 0.65). IK Anova between G2 zones was: A vs. C and D (P < 0.000001). Staff prescription adherence was 81.3% (G1) vs. 84.1% (G2) (P = 0.02). Conclusion In conclusion, an optimal Qb can de prescribed with DALP of -200 mmHg. Staff adherence to DLAP treatment prescription could be reached up to 81.3% in catheters and 84.1% in AV fistulae.

Cardiovascular disease is a major cause of morbidity and mortality in end-stage renal disease (ESRD). Renal transplant is known to improve left ventricle hypertrophy and systolic dysfunction in selected groups of patients.We assessed myocardial perfusion, wall motion and functional parameters by single photon emission computed tomography (SPECT) and Gated-SPECT in 30 consecutive ESRD patients with normal coronary angiograms before and after renal transplantation.Uremic cardiomyopathy improved significantly after the transplant. The proportion of patients with angina decreased from 26 to 0%; the frequency of cardiomegaly decreased from 57 to 20% (p0.01); the frequency of segments with perfusion defects decreased from 42.7 to 10.2% (p0.001); the proportion of patients with low left ventricular ejection fraction (LVEF) dropped from 53.3 to 20% (p0.001); and mean LVEF increased from (48.0 +/- 9.7% to 58.2 +/- 8.2%). Similarly, the proportion of segments showing systolic wall thickening, hypokinesia and dyskinesia also decreased significantly after renal transplant (p0.01).Uremic cardiomyopathy may be potentially reversible in patients with normal angiographic coronary arteries after renal transplant in a relatively short period of time. SPECT and Gated-SPECT are objective gateway methods to determine myocardial perfusion, hypokinesia, dyskinesia, and functional parameters (left ventricular ejection fraction and systolic wall thickening) and may be useful to establish diagnostic, coronariographic, prognostic, and therapeutic indications.

The hypothesis that the Poincaré plot indexes of heart rate variability (HRV) detect dynamic changes after haemodialysis (HD) over the HRV in haemodynamically stable chronic renal failure (CRF) patients was examined. Minor axis (SD1), major axis (SD2) and the SD1/SD2 ratio were compared against standard HRV indexes in time and frequency domain, in a group of healthy subjects and in a group of CRF patients before and after HD. These indexes were estimated from Poincaré plots reconstructed with lags of one, two and four heartbeats. The surrogate data analysis technique was applied in order to discern if only random components or linear features of HRV contribute to its dynamics. None of the standard linear HRV indexes changed after HD. The Poincaré plot indexes measured from CRF patients were smaller than the ones measured from healthy subjects. In CRF patients the SD1/SD2 ratio decreased after HD, when a lag of four heartbeats was used (0.68 +/- 0.19 before HD versus 0.55 +/- 0.12 after HD, P0.05). The presence of deterministic components in HRV were confirmed for all measures of the SD1/SD2 ratio. Moreover, a loss of non-linear components after HD was detected by the surrogate analysis over the SD1/SD2 ratio with a lag of four heartbeats. In conclusion, the SD1/SD2 ratio measured at lag of 4 heartbeats capture dynamic changes after HD upon the HRV of CRF patients that are not solely related to linear autocorrelations of HRV. This suggests that the SD1/SD2 ratio reflects non-linear information of HRV.

It is now well recognised that the renin-angiotensin system plays a key role in the control of blood pressure not only through circulating angiotensin II but through its interaction with the autonomic and central nervous systems. Angiotensin-converting enzyme (ACE) inhibitors have proved to be effective in lowering blood pressure in different types of hypertension. This study evaluates the antihypertensive effects of enalapril, a new, potent, long acting ACE inhibitor. 50 patients with uncomplicated essential hypertension were included in 4 groups. Group I was used to compare the effects of enalapril and propranolol on blood pressure, renal function, plasma renin activity, aldosterone excretion and plasma lipids in 24 patients after 23 weeks. Group II was used to evaluate long term effects (48 weeks) of these drugs in 13 patients. Group III included 32 patients that received enalapril as monotherapy for 6 to 12 weeks. Group IV was studied to estimate the antihypertensive effect of low doses of hydrochlorothiazide in 18 patients receiving enalapril. The effect on mean blood pressure was similar with enalapril and propranolol (enalapril 117 versus 103 mm Hg and propranolol 115 versus 104 mm Hg); however, the glomerular filtration rate decreased with propranolol (105 versus 87 ml/min; p less than 0.05) and was unaltered with enalapril (102 versus 98 ml/min). Triglycerides rose with propranolol (179 versus 231 mg/dl; p less than 0.05) and did not change with enalapril (157 versus 121 mg/dl). In the long term, antihypertensive effects were similar and no significant side effects were observed. In 14/32 patients blood pressure became normal with enalapril alone. Low doses of hydrochlorothiazide (12.5 to 25 mg) decreased mean blood pressure by 10mm Hg when added to enalapril. The antihypertensive effect of enalapril was similar to that of propranolol; however, the lowering effect on glomerular filtration rate of propranolol did not occur with enalapril. A slight rise in triglycerides occurred only with propranolol. No significant side effects were observed with either propranolol or enalapril. Used as monotherapy, enalapril normalised blood pressure in 44% of cases. Addition of low doses of hydrochlorothiazide significantly increased the antihypertensive effect of enalapril.

Fosinopril prevents hyperfiltration and decreases proteinuria in post-transplant hypertensives. Hypertension and renal mass reduction induce glomerular hypertension (GH), hyperfiltration (HF) and renal injury. GH may contribute to allograft loss in post-transplant hypertensive patients (PT × HT). HF and GH may be evaluated by renal response to acute protein intake (API). Since ACE inhibition may prevent GH, the effects of fosinopril (Fos) were evaluated in 10PT × HT on azathioprine and prednisone. Patients received 5 to 40 mg/day of Fos during 12 months.Baseline MAP (111.1 ± 2.9mm Hg) was significantly reduced by 10 to 12mm Hg, rising to 114.7 ± 2.7mm Hg after Fos was administered. GFR (63.7 ± 5.9 ml/min) decreased after 4 (48.1 ± 4.6, P < 0.05) and 12 months (50.7 ± 4.6, P < 0.05), rising to 59.4 ± 5.6 after Fos was given. There was no GFR response to API before and after one month of Fos, however, a clear response became apparent at 4 (+ 27% P < 0.05), and 12 months (+ 18%, P < 0.05), disappearing after Fos discontinuation. Proteinuria (918.8 ± 710.6 mg/d) decreased after 4 (72.3 ± 21.6 mg/d, P < 0.05) and 12 months, rising to 297.8 ± 172.3 mg/day after therapy. GFR response to API in 22 controls and 17 uninephrectomized donors was 13 and 11%, respectively. Lack of response to API in PT × HT suggests HF and GH. Reduction of GFR, restoration of response to API and reduction of proteinuria, indicate that ACE inhibition with fosinopril ameliorates HF and GH. This effect may be beneficial in preventing hemodynamic-mediated allograft injury.

HD and HDF as hemodialytic therapies normally alter patient's haemodynamic stability, due to the inflammatory response to extracorporeal blood circuit, producing increment of the core temperature (+1.0 degrees C). However, such increase in temperature could be controlled by lowering dialysate's temperature using two main modalities techniques (isothermic and thermoneural) with different patient's thermal balance consequences, not yet well studied. In this work, energy expenditure (EE) was measured by indirect calorimetry in a group of 12 patients waiting kidney transplant. In each patient, EE was assessed (as a power generation) during isothermic and thermoneutral modalities as a manner of cross and prospective study (a) at before therapy, (b) during therapy and (c) at the end of the HDF therapy. Wheraeas, power extraction was measured by a BTM (Blood Temperature Monitor from Fresenius Inc) in order to determine power balance in a thermodynamic model of the extracorporeal circuit. The results showed significant differences in the power balance when EE at during therapy was subtracted from the EE at before therapy. Then, EE increments were 32 Kcal/4-hours during isothermic and 3.6 Kcal/4-hours during thermoneutral HDF sessions (p0.05). While, BTM totals power extraction was 91 and 16.1 Kcal/4-hours (p0.05), respectively. Additionally, it was estimated a 12% of EE/day increment during HDF-isothermic at during therapy stage compared with none significative EE increment during thermoneutral modality. The statistical evidence confirmed the expected hypothesis that both modalities affect in different manner the patient's EE. Also, we conclude there is no satisfactory data interpretation when the thermodynamic model was applied expecting null balance between EE increment and BTM power extraction. Therefore, these findings force to think there is need of different BTM design and measurement setting with ability to follow dynamic patient's EE changes with the purpose to achieve a better power balance.