Cooling dialysate during in-center hemodialysis: Beneficial and deleterious effects

Evaluation of effect of cooled haemodialysis on cognition in patients with end-stage kidney disease (ECHECKED) feasibility randomised controlled trial results

BACKGROUND

Cognitive impairment is common in haemodialysis patients with no known beneficial interventions. Cooler dialysate slows brain white-matter changes, but its effect on cognition is unknown. This feasibility trial was performed to inform a fully-powered, randomised trial to assess this.

METHODS

We aimed to randomise (1:1) 90 haemodialysis patients to this double-blinded, randomised controlled feasibility trial to standard care (dialysate-temperature 36.5 °C) or intervention (35 °C). Eligible patients were adult chronic haemodialysis recipients with no established diagnosis of dementia or psychiatric disease. The primary outcome was change in Montreal Cognitive Assessment (MoCA) score at 12-months. Secondary outcomes included recruitment and attrition rates, reasons for non-recruitment, intradialytic hypotension, depression, patient burden, computerised cognition test battery, and quality of life.

FINDINGS

Of 334 patients screened, 160 were eligible. 99 declined mainly for the extra non-dialysis day study visits. Sixty-one patients consented, 43 randomised - 20 in standard care, 23 in intervention arms; 13 withdrew for non-dialysis day visits and 5 without reason before randomisation. 27 patients (12 standard care, 15 intervention) completed the trial - 5 died, 1 transplanted, 4 withdrew consent, and 6 could not attend due to the pandemic. Low temperature dialysis was well tolerated. There was no difference in change in MoCA from baseline to 12 months between the standard and intervention arms; 1.0 (-2.8-3.0, p = 0.755) and - 2.0 (-1.0 - -4.0, p = 0.047) respectively. There were no differences between groups on any secondary measures. There were no significant adverse events reported.

DISCUSSION

The trial was significantly affected by the COVID-19 pandemic contributing to an attrition rate of 27%. The non-dialysis day research visits were mainly responsible for low recruitment and consent withdrawal. There are several learning points, described in the article, which will inform design of definitive trials in this area in the future.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT03645733. Registration date 24/08/2018.

The Acute, Combined, and Separate Effects of Cold Hemodialysis and Intradialytic Exercise in Insulin Sensitivity and Glucose Disposal

Hemodialysis (HD) patients suffer from multiple health problems, including severe insulin resistance. Both cold dialysis and intradialytic exercise training could elicit health benefits; however, it is still unknown whether the combination of those two approaches could enhance overall health. The current study aimed to evaluate the separate and combined acute effects of a single session of cold dialysis and intradialytic exercise in parameters related to insulin sensitivity and glucose disposal. Ten HD patients (57.2 ± 14.9 years) participated in the study. Each patient participated in four different scenarios during HD: a) typical dialysis with dialysate temperature at 37°C (TD), b) cold dialysis with dialysate temperature at 35°C, c) typical HD combined with a single exercise bout, d) cold dialysis combined with a single exercise bout. Glucose disposal and insulin resistance were assessed immediately after the end of the HD session. None of the examined parameters significantly differed between the four scenarios ( p > 0.05). However, slight numerical changes and moderate to high effect size ( d : 0.50-0.85) were observed between TD versus cold dialysis and TD versus TD + exercise in glucose and insulin disposal rates. A single session of cold and TD with intradialytic exercise may provide an "acute" time-efficient stimulus for consecutively improving glucose disposal and insulin sensitivity.

Does cooled dialysate still have a role in reducing intradialytic stress? Implications of the MyTEMP trial

PURPOSE OF REVIEW

There is an excess of cardiovascular morbidity and mortality in the maintenance haemodialysis population. Targeting traditional risk factors (e.g. hypercholesterolaemia) do not improve cardiovascular outcomes. Repeated myocardial stunning during haemodialysis is an important nontraditional risk, resulting in pathological cardiac remodelling and fibrosis. This review explores dialysate cooling as a management strategy to promote haemodynamic stability, reduce myocardial injury, and improve cardiovascular disease outcomes for individuals receiving maintenance haemodialysis.

RECENT FINDINGS

Observational data and small interventional studies demonstrate dialysate cooling has the potential to reduce end-organ damage and provide cardioprotection, renal protection and neuroprotection compared with standard care. These data are limited by the small sample sizes, short follow-up times and lack of long-term patient important outcomes. The MyTEMP study, a multicentre pragmatic randomized controlled trial, demonstrated cooled dialysate (0.5°C below body temperature) vs. standard care did not improve cardiovascular outcomes for prevalent haemodialysis patients.

SUMMARY

Dialysate cooling has been widely adopted into routine clinical practice; the MyTEMP study challenges the unit-level approach to implementing dialysate cooling. Due to methodological limitations, the absence of other important patient outcome measures, and lack of granularity of patient-level data, dialysate cooling should not be hastily removed from all dialysis care and warrants further research.

Could cooling dialysate improve inflammatory and nutritional status of hemodialysis patients?

BACKGROUND

It has been shown that dialysate cooling (lowering the dialysate temperature to 0.5 °C below central body temperature) reduces the incidence of intradialytic hypotension. Other influences on hemodialysis patients, however, have not been adequately investigated. The purpose of this study was to determine the impact of individualized dialysate cooling on nutritional and inflammatory parameters in chronic hemodialysis (HD) patients.

METHODS

Seventy HD patients were separated into two groups: group A: (control group) standard dialysate temperature was 37 °C, and group B: (intervention group) dialysate temperature was 0.5 °C below core body temperature. In addition to routine laboratory tests, blood pressure, anthropometric measurements, inflammatory markers, and the malnutrition inflammation score (MIS) were calculated.

RESULTS

After six months of dialysate cooling, intradialytic hypotension episodes were much less prevalent in the intervention group (p = 0.001). Serum ferritin, transferrin saturation (TSAT), high sensitive C-reactive protein (HS-CRP), and Interleukin-6 (IL-6) reduced following dialysate cooling, whereas serum albumin rose. In the control group, IL-6 dropped but serum ferritin, TSAT, albumin, and HS-CRP rose. In both groups, hemoglobin levels dropped, and erythrocyte sedimentation rate (ESR) rose, both groups' midarm muscle circumference and MIS worsened.

CONCLUSION

Cold dialysate decreased intradialytic hypotension with no significant improvement of the nutritional and inflammatory surrogates. However, more studies including larger number of patients with longer duration of follow up are required to adequately assess its effect on inflammation and nutrition in chronic hemodialysis patients.

Cognitive impairment in different hemodialysis techniques

Background

Cognitive impairment is one of the most common, often untreated, comorbidities affecting patients with chronic kidney disease treated with hemodialysis. Increased mortality, poor compliance, depression, and poor quality of life were all linked to cognitive impairment in the hemodialysis population. The intradialytic exercise proved to be beneficial in improving patients’ quality of life, among other positive effects. Cooling dialysate has various positive effects, including improved patients’ mood and decreased hypotensive episodes during hemodialysis. The study aims to assess the effect of intradialytic exercise and cool hemodialysis on cognitive function in patients on hemodialysis.

Results

The study showed no significant effect of both interventions on the patient’s cognitive functions. However, cooling dialysate showed an improvement in the severity of depressive symptoms by Beck’s Depression Inventory II (p = 0.02). On the other hand, Mini-International Neuropsychiatric Interview showed an increase of patients diagnosed with depression in the intradialytic exercise group.

Conclusions

Both interventions had no significant effect on the mean scores of the Montreal Cognitive Assessment, which are lower in our sample than in the general population (23.9–25). Potential implications include the importance of managing psychiatric comorbidities in patients on hemodialysis. Cooling dialysate can be adopted to alleviate depressive symptoms in patients on hemodialysis.

Effects of hemodialysis with cooled dialysate on high-sensitivity cardiac troponin I and brain natriuretic peptide

BACKGROUND

Hemodialysis (HD) triggers recurrent and cumulative ischemic insults to the brain and the heart. Cooled dialysate may have a protective effect on major organs and improve hemodynamic tolerability of dialysis. The aim of the study was to compare HD with cooled dialysate with routine dialysis in terms of hemodynamic stability and levels of high-sensitivity Troponin I (hs-TnI) and N-terminal pro b-type natriuretic peptide (NTproBNP) pre and postdialysis.

METHODS

The 45 patients were randomized into two groups. The first group received a 35.5°C dialysate first (hypothermic dialysis) and the second group a 36.5°C dialysate first (routine dialysis). Then groups crossed over, so each group received the alternate dialysate (self-controls) For each patient, the first sample was collected at the beginning of dialysis, and a second sample was taken at the end of dialysis.

RESULTS AND CONCLUSION

hs-TnI and NTproBNP increased after routine HD by 10.7 ng\ml (p < 0.001) and (12.0 pg/μl) (p < 0.001), respectively, and by -3.1 ng\ml (p = 0.25) and (4.3 pg/μl) (p < 0.001), respectively after hypothermic HD. Our study results showed a tendency towards less rise in hsTnI and NTproBNP during hypothermic HD (35.5°C) as compared to routine HD (36.5°C). Neither arm experienced statistically significant changes in blood pressure. Further studies in larger cohorts and long follow up are warranted in order to confirm that lower rise in (hs-TnI) and NTproBNP actually translate into lower clinical risk for cardiovascular events.

Application and Feasibility Study of Integrated Nursing Information Construction in Nephrology Nursing

With the continuous deepening of medical reforms and the continuous attempts and explorations of various management models, the traditional health care model is undergoing tremendous changes, and patients' needs for medical institutions are becoming more and more comprehensive. Medical institutions are meeting the needs of providing medical services to patients at the same time. It is even more necessary to change our thinking and enhance the service concept. This article is based on case-based deep learning hospital nursing business process reengineering and the application and feasibility study of integrated nursing information construction in nephrology nursing. This article uses the literature analysis method, the social survey method, and other methods to discuss the construction of integrated nursing information. On the one hand, the content of this article uses the concept of process reengineering to analyze the current development status and existing problems of the hospital care industry and find countermeasures to solve problems. On the other hand, the main research content of this article is the construction of integrated nursing information and its analysis of the application and feasibility of nursing in the nephrology department. At the same time, under the background of the rapid development of the mobile Internet, we will carry out extended thinking on the continuous transformation of the construction of nursing information. According to the survey results, 87.5% of patients in the nephrology department are dissatisfied with the current hospital's work efficiency, and 85.7% of the nursing staff in the nephrology department are generally satisfied with the information management of the current department. After the implementation of the hospital information integration system, patient satisfaction is as high as 98.2%, and the satisfaction of medical staff reached 94.2%. The construction of integrated nursing information has played a great role in the application of nephrology nursing.

The Effects of Cool Dialysate on Vital Signs, Adequacy and Complications during Hemodialysis

BACKGROUND

Cooling the dialysate is an important factor that contributes to the hemodynamic stability in patients during hemodialysis. The aim of this study was to determine the effect of cool dialysate on vital signs, and the adequacy and common complications of hemodialysis.

MATERIALS AND METHODS

The present crossover, triple-blind, clinical trial was performed on 62 dialysis patients, who were selected through stratified block randomization. First, one group underwent hemodialysis using a cool dialysate (35°C), and the other received routine hemodialysis (36.5°C). Each patient received a total of eight hemodialysis sessions. Then, treatment methods were swapped, and each group received the other group's method. The patients' blood pressure, pulse rate, and temperature were measured before dialysis, and in the first, second, third, and fourth hours of dialysis. The frequency of common complications of hemodialysis and dialysis efficacy were measured. The marginal model and Generalized Estimating Equations (GEE) were used to analyze the data.

RESULTS

The participants' systolic (p = 0.01) and diastolic blood pressures significantly increased with a decrease in temperature (p = 0.005). The patients' pulse rate (p = 0.143), adequacy of dialysis (p = 0.922), and common complications of hemodialysis did not significantly differ between the two temperatures (p > 0.05).

CONCLUSIONS

Reducing dialysate temperature from 36.5 to 35°C led to hemodynamic stability; the blood pressure of the patients undergoing hemodialysis was more stable with the cool dialysate method and the number of drops in the blood pressure during the hemodialysis was reduced.

Effect of Cool Dialysate on Depression in Patients with Chronic Renal Failure Treated with Hemodialysis: A Randomized Clinical Trial

Background: Depression is one of the most common psychiatric problems in hemodialysis patients. Objectives: This study aimed to evaluate the effect of cool dialysate on depression in patients with chronic renal failure treated with hemodialysis. Methods: This randomized clinical trial was performed on 66 hemodialysis patients suffering from depression. Patients were selected by a convenience sampling method and divided equally into intervention and control groups randomly by permuted block allocation, each group containing 33 patients. Data were acquired with the Beck Depression inventory-I. The intervention and control groups underwent one month of treatment with cool dialysate at 35.5 and 37°C, respectively. The severity of depression for each group was measured at the end of each treatment stage and two weeks after the intervention. Data were analyzed using R version 25 software with a confidence level of 95%. Results: There was no statistically significant difference between the control and intervention groups before and after the intervention (P-values more than 0.05). While the mean of depression severity for the control group decreased from 26.15 ± 1.46 to 22.24 ± 2.00 (P-values < 0.01), the mean of depression severity for the intervention group decreased from 25.56 ± 1.28 to 22.41 ± 1.65 by the intervention (P-value > 0.05). Conclusions: The application of cool dialysate as a non-pharmacological method did not significantly reduce the severity of depression in patients undergoing hemodialysis. Therefore, it is advised to perform further studies that include more research units from different geographical locations, considering a longer intervening duration.

Exploring the Link Between Hepatic Perfusion and Endotoxemia in Hemodialysis

Introduction

The liver receives gut-derived endotoxin via the portal vein, clearing it before it enters systemic circulation. Hemodialysis negatively impacts the perfusion and function of multiple organs systems. Dialysate cooling reduces hemodialysis-induced circulatory stress and protects organs from ischemic injury. This study examined how hemodialysis disrupts liver hemodynamics and function, its effect on endotoxemia, and the potential protective effect of dialysate cooling.

Methods

Fifteen patients were randomized to receive either standard (36.5°C dialysate temperature) or cooled (35.0°C) hemodialysis first in a two-visit crossover trial. We applied computed tomography (CT) liver perfusion imaging to patients before, 3 hours into and after each hemodialysis session. We measured hepatic perfusion and perfusion heterogeneity. Hepatic function was measured by indocyanine green (ICG) clearance. Endotoxin levels in blood throughout dialysis were also measured.

Results

During hemodialysis, overall liver perfusion did not significantly change, but portal vein perfusion trended towards increasing (P = 0.14) and perfusion heterogeneity significantly increased (P = 0.038). In addition, ICG clearance decreased significantly during hemodialysis (P = 0.016), and endotoxin levels trended towards increasing during hemodialysis (P = 0.15) and increased significantly after hemodialysis (P = 0.037). Applying dialysate cooling trended towards abrogating these changes but did not reach statistical significance compared to standard hemodialysis.

Conclusion

Hemodialysis redistributes liver perfusion, attenuates hepatic function, and results in endotoxemia. Higher endotoxin levels in end-stage renal disease (ESRD) patients may result from the combination of decreased hepatic clearance function and increasing fraction of liver perfusion coming from toxin-laden portal vein during hemodialysis. The protective potential of dialysate cooling should be explored further in future research studies.

Evaluation of the effect of Cooled HaEmodialysis on Cognitive function in patients suffering with end-stage KidnEy Disease (E-CHECKED): feasibility randomised control trial protocol

BACKGROUND

Cognitive impairment is common in haemodialysis (HD) patients and is associated independently with depression and mortality. This association is poorly understood, and no intervention is proven to slow cognitive decline. There is evidence that cooler dialysis fluid (dialysate) may slow white matter changes in the brain, but no study has investigated the effect of cooler dialysate on cognition. This study addresses whether cooler dialysate can prevent the decline in cognition and improve quality of life (QOL) in HD patients.

METHODS

This is a multi-site prospective randomised, double-blinded feasibility trial.

SETTING

Four HD units in the UK.

PARTICIPANTS AND INTERVENTIONS

Ninety HD patients randomised (1:1) to standard care (dialysate temperature 36.5 °C) or intervention (dialysate temperature 35 °C) for 12 months.

PRIMARY OUTCOME MEASURE

Change in cognition using the Montreal Cognitive Assessment (MoCA).

SECONDARY OUTCOME MEASURES

Recruitment and attrition rates, reasons for non-recruitment, frequency of intradialytic hypotension, depressive symptom scores, patient and carers burden, a detailed computerised cognitive test and QOL assessments.

ANALYSIS

mixed method approach, utilising measurement of cognition, questionnaires, physiological measurements and semi-structured interviews.

DISCUSSION

The results of this feasibility trial will inform the design of a future adequately powered substantive trial investigating the effect of dialysate cooling on prevention and/or slowing in cognitive decline in patients undergoing haemodialysis using a computerised battery of neuro-cognitive tests. The main hypothesis that would be tested in this future trial is that patients treated with regular conventional haemodialysis will have a lesser decline in cognitive function and a better quality of life over 1 year by using cooler dialysis fluid at 35 °C, versus a standard dialysis fluid temperature of 36.5 °C. This also should reflect in improvements in their abilities for activities of daily living and therefore reduce carers' burden. If successful, the treatment could be universally applied at no extra cost.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03645733 . Registered retrospectively on 24 August 2018.

An update review of intradialytic hypotension: concept, risk factors, clinical implications and management

Intradialytic hypotension (IDH) is a frequent and serious complication of chronic haemodialysis, linked to adverse long-term outcomes including increased cardiovascular and all-cause mortality. IDH is the end result of the interaction between ultrafiltration rate (UFR), cardiac output and arteriolar tone. Thus excessive ultrafiltration may decrease the cardiac output, especially when compensatory mechanisms (heart rate, myocardial contractility, vascular tone and splanchnic flow shifts) fail to be optimally recruited. The repeated disruption of end-organ perfusion in IDH may lead to various adverse clinical outcomes affecting the heart, central nervous system, kidney and gastrointestinal system. Potential interventions to decrease the incidence or severity of IDH include optimization of the dialysis prescription (cool dialysate, UFR, sodium profiling and high-flux haemofiltration), interventions during the dialysis session (midodrine, mannitol, food intake, intradialytic exercise and intermittent pneumatic compression of the lower limbs) and interventions in the interdialysis period (lower interdialytic weight gain and blood pressure–lowering drugs). However, the evidence base for many of these interventions is thin and optimal prevention and management of IDH awaits further clinical investigation. Developing a consensus definition of IDH will facilitate clinical research. We review the most recent findings on risk factors, pathophysiology and management of IDH and, based on this, we call for a new consensus definition of IDH based on clinical outcomes and define a roadmap for IDH research.

Cardiac stunning during haemodialysis: the therapeutic effect of intra-dialytic exercise

Background

Cardiovascular risk is elevated in end-stage renal disease. Left ventricular (LV) dysfunction is linked to repetitive transient ischaemia occurring during haemodialysis (HD). Cardiomyocyte ischaemia results in ‘cardiac stunning’, evidenced by regional wall motion abnormalities (RWMAs). Ischaemic RWMA have been documented during HD resulting in maladaptive cardiac remodelling and increased risk of heart failure. Intra-dialytic exercise is well tolerated and can improve quality of life and functional capacity. It may also attenuate HD-induced cardiac stunning.

Methods

This exploratory study aimed to assess the effect of intra-dialytic cycle ergometry on cardiac stunning. Twenty exercise-naïve participants on maintenance HD (mean ± SD, 59 ± 11 years) underwent resting echocardiography and maximal cardiopulmonary exercise testing. Subsequently, cardiac stunning was assessed with myocardial strain-derived RWMAs at four time points during (i) standard HD and (ii) HD with 30 min of sub-maximal intra-dialytic cycle ergometry at a workload equivalent to 90% oxygen uptake at the anaerobic threshold (VO₂AT). Central haemodynamics and cardiac troponin I were also assessed.

Results

Compared with HD alone, HD with intra-dialytic exercise significantly reduced RWMAs after 2.5 h of HD (total 110 ± 4, mean 7 ± 4 segments versus total 77 ± 3, mean 5 ± 3, respectively; P = 0.008). Global cardiac function, intra-dialytic haemodynamics and LV volumetric parameters were not significantly altered with exercise.

Conclusions

Intra-dialytic exercise reduced cardiac stunning. Thirty minutes of sub-maximal exercise at 90% VO₂AT was sufficient to elicit acute cardio-protection. These data potentially demonstrate a novel therapeutic effect of intra-dialytic exercise.

Sudden Cardiac Death in End-Stage Renal Disease

The challenge presented by sudden cardiac death in dialysis patients is to better define risk factors and delineate multiple etiologies. Only then can therapy be tailored to the highest risk patients and the incidence of sudden cardiac death be reduced. This article details the many possible etiologies and presents a brief overview of more recent research that may in the future prove of great benefit in improving the mortality of our patients with end-stage renal disease.

Dialysate temperature reduction for intradialytic hypotension for people with chronic kidney disease requiring haemodialysis

BACKGROUND

Intradialytic hypotension (IDH) is a common complication of haemodialysis (HD), and a risk factor of cardiovascular morbidity and death. Several clinical studies suggested that reduction of dialysate temperature, such as fixed reduction of dialysate temperature or isothermal dialysate using a biofeedback system, might improve the IDH rate.

OBJECTIVES

This review aimed to evaluate the benefits and harms of dialysate temperature reduction for IDH among patients with chronic kidney disease requiring HD, compared with standard dialysate temperature.

SEARCH METHODS

We searched Cochrane Kidney and Transplant's Specialised Register up to 14 May 2019 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs), cross-over RCTs, cluster RCTs and quasi-RCTs were included in the review.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted information including participants, interventions, outcomes, methods of the study, and risks of bias. We used a random-effects model to perform quantitative synthesis of the evidence. We assessed the risks of bias for each study using the Cochrane 'Risk of bias' tool. We assessed the certainty of evidence using Grades of Recommendation, Assessment, Development and Evaluation (GRADE).

MAIN RESULTS

We included 25 studies (712 participants). Three studies were parallel RCTs and the others were cross-over RCTs. Nineteen studies compared fixed reduction of dialysate temperature (below 36°C) and standard dialysate temperature (37°C to 37.5°C). Most studies were of unclear or high risk of bias. Compared with standard dialysate, it is uncertain whether fixed reduction of dialysate temperature improves IDH rate (8 studies, 153 participants: rate ratio 0.52, 95% CI 0.34 to 0.80; very low certainty evidence); however, it might increase the discomfort rate compared with standard dialysate (4 studies, 161 participants: rate ratio 8.31, 95% CI 1.86 to 37.12; very low certainty evidence). There were no reported dropouts due to adverse events. No study reported death, acute coronary syndrome or stroke.Three studies compared isothermal dialysate and thermoneutral dialysate. Isothermal dialysate might improve the IDH rate compared with thermoneutral dialysate (2 studies, 133 participants: rate ratio 0.68, 95% CI 0.60 to 0.76; I² = 0%; very low certainty evidence). There were no reports of discomfort rate (1 study) or dropouts due to adverse events (2 studies). No study reported death, acute coronary syndrome or stroke.

AUTHORS' CONCLUSIONS

Reduction of dialysate temperature may prevent IDH, but the conclusion is uncertain. Larger studies that measure important outcomes for HD patients are required to assess the effect of reduction of dialysate temperature. Six ongoing studies may provide much-needed high quality evidence in the future.

Renal Perfusion during Hemodialysis: Intradialytic Blood Flow Decline and Effects of Dialysate Cooling

BACKGROUND

Residual renal function (RRF) confers survival in patients with ESRD but declines after initiating hemodialysis. Previous research shows that dialysate cooling reduces hemodialysis-induced circulatory stress and protects the brain and heart from ischemic injury. Whether hemodialysis-induced circulatory stress affects renal perfusion, and if it can be ameliorated with dialysate cooling to potentially reduce RRF loss, is unknown.

METHODS

We used renal computed tomography perfusion imaging to scan 29 patients undergoing continuous dialysis under standard (36.5°C dialysate temperature) conditions; we also scanned another 15 patients under both standard and cooled (35.0°C) conditions. Imaging was performed immediately before, 3 hours into, and 15 minutes after hemodialysis sessions. We used perfusion maps to quantify renal perfusion. To provide a reference to another organ vulnerable to hemodialysis-induced ischemic injury, we also used echocardiography to assess intradialytic myocardial stunning.

RESULTS

During standard hemodialysis, renal perfusion decreased 18.4% (P<0.005) and correlated with myocardial injury (r=-0.33; P<0.05). During sessions with dialysis cooling, patients experienced a 10.6% decrease in perfusion (not significantly different from the decline with standard hemodialysis), and ten of the 15 patients showed improved or no effect on myocardial stunning.

CONCLUSIONS

This study shows an acute decrease in renal perfusion during hemodialysis, a first step toward pathophysiologic characterization of hemodialysis-mediated RRF decline. Dialysate cooling ameliorated this decline but this effect did not reach statistical significance. Further study is needed to explore the potential of dialysate cooling as a therapeutic approach to slow RRF decline.

The effects of cool dialysate on quality of sleep among patients undergoing hemodialysis: A randomized clinical trial

INTRODUCTION

Low quality of sleep is a common problem among hemodialysis patients. This study was conducted to evaluate the effect of a cold dialysis solution on the quality of sleep in patients undergoing hemodialysis.

METHODOLOGY

This double-blind clinical trial was performed on 26 hemodialysis patients with chronic renal failure and sleep disorders in the dialysis center of Sabzevar, Iran, in 2016-2017. Of the 26 patients, 13 each were allocated to the intervention and control groups. The patients in both groups received 4 weeks of hemodialysis (3 sessions per week) using a standard solution with a temperature of 37°C. In the next stage, the control group continued to receive the standard-temperature dialysis, while the intervention group received dialysis using a solution with a temperature of 35.5°C for 4 weeks (3 sessions per week). The Pittsburgh Sleep Quality Index was used to assess and compare the quality of sleep before and after the intervention in the two groups. Data were analyzed using R 1.2.3 software, at 95% confidence level.

RESULTS

Although the mean scores of sleep quality were not significantly different between the intervention (9.53 ± 3.12) and control (11.23 ± 3.37) groups at baseline, postintervention, significant differences were observed (intervention group: 4.7 ± 4.55; control group: 10.61 ± 2.69; P < 0.001).

CONCLUSION

This study showed that dialysis with cold solution is a simple, cost-effective, and nonpharmacological method that can be used to improve sleep quality in patients undergoing hemodialysis.

Existing capacity for renal replacement therapy and site-specific practices for managing acute kidney injury at centers participating in the BaSICS trial

OBJECTIVE

To investigate the existing capacity for renal replacement therapy and site-specific practices for managing acute kidney injury at centers participating in the BaSICS trial.

METHODS

A questionnaire was provided to the chairs of 61 intensive care units enrolled in a randomized clinical trial in Brazil. A total of 124 physicians completed the questionnaire.

RESULTS

Approximately 15% of the patients admitted to the analyzed intensive care units received renal replacement therapy at the time of data collection. At least one renal replacement method was available in all of the analyzed units. Continuous methods were available more frequently at the private units than at the public units. The time from indication to onset of treatment was longer at the public units than at private units. The main obstacles to treatment initiation at public intensive care units were related to the availability of equipment and personnel, while the main bottleneck at private units was the nephrologist assessment. A considerable proportion of the participants stated that they would change their approach to renal replacement therapy if there were no limitations on the availability of methods in their units.

CONCLUSION

There was wide variation in the availability of resources for renal replacement therapy and in the management of acute kidney injury in Brazilian intensive care units. This information should be taken into account when planning clinical trials focused on this topic in Brazil.

Hemodynamic Instability during Dialysis: The Potential Role of Intradialytic Exercise

Acute haemodynamic instability is a natural consequence of disordered cardiovascular physiology during haemodialysis (HD). Prevalence of intradialytic hypotension (IDH) can be as high as 20–30%, contributing to subclinical, transient myocardial ischemia. In the long term, this results in progressive, maladaptive cardiac remodeling and impairment of left ventricular function. This is thought to be a major contributor to increased cardiovascular mortality in end stage renal disease (ESRD). Medical strategies to acutely attenuate haemodynamic instability during HD are suboptimal. Whilst a programme of intradialytic exercise training appears to facilitate numerous chronic adaptations, little is known of the acute physiological response to this type of exercise. In particular, the potential for intradialytic exercise to acutely stabilise cardiovascular hemodynamics, thus preventing IDH and myocardial ischemia, has not been explored. This narrative review aims to summarise the characteristics and causes of acute haemodynamic instability during HD, with an overview of current medical therapies to treat IDH. Moreover, we discuss the acute physiological response to intradialytic exercise with a view to determining the potential for this nonmedical intervention to stabilise cardiovascular haemodynamics during HD, improve coronary perfusion, and reduce cardiovascular morbidity and mortality in ESRD.

The Effect of Cold Dialysis in Motor and Sensory Symptoms of RLS/WED Occurring During Hemodialysis: A Double-Blind Study

Restless legs syndrome/Willis-Ekbom disease (RLS/WED) is a common sensorimotory disorder affecting almost 30% of hemodialysis (HD) patients. RLS/WED induces discomfort during rest hours, and its symptoms have also been observed during HD sessions. Anecdotal reports suggest that cooling the dialysate solution during dialysis could help patients overcome those symptoms and improve restlessness. The aim of this double-blind study was to assess whether a reduction of the dialysate temperature by 1°C could reduce motor and sensory symptoms of RLS/WED occurring during HD. Thirty-two HD patients participated in the study. Patients were divided into two groups: the RLS (N=16) and the non-RLS groups (N=16). Patients were studied on two different scenarios for two consecutive HD sessions, 1 week apart: 1) standard temperature of the dialysate (37°C) and 2) low temperature of the dialysate (36°C cold dialysis scenario). In all sessions, motor (leg movement per hour of HD [LM/hHD]) and sensory symptoms were assessed. The reduction of dialysate temperature by 1°C was effective in reducing motor symptoms as they assessed the LM/hHD by 36% only in patients with RLS, while a significant interaction was found between "LM/hHD affected by temperature" and "RLS status" (p = 0.039). Sensory symptoms also reduced by 10% after the reduction of the dialysate temperature. The reduction of the dialysate temperature by 1°C reduced motor symptoms by 36-54% and sensory symptoms by 10% in HD patients with RLS/WED. Cold dialysis could be considered a safe nonpharmacological approach for the amelioration of RLS/WED symptoms occurring during HD.

Cold dialysis and its impact on renal patients’ health: An evidence-based mini review

Chronic renal disease is associated with advanced age, diabetes, hypertension, obesity, musculoskeletal problems and cardiovascular disease, the latter being the main cause of mortality in patients receiving haemodialysis (HD). Cooled dialysate (35 °C-36 °C) is recently employed to reduce the incidence of intradialytic hypotension in patients on chronic HD. The studies to date that have evaluated cooled dialysate are limited, however, data suggest that cooled dialysate improves hemodynamic tolerability of dialysis, minimizes hypotension and exerts a protective effect over major organs including the heart and brain. The current evidence-based review is dealing with the protective effect of cold dialysis and the benefits of it in aspects affecting patients’ quality of care and life. There is evidence to suggest that cold dialysis can reduce cardiovascular mortality. However, large multicentre randomized clinical trials are urgently needed to provide further supporting evidence in order to incorporate cold dialysis in routine clinical practice.

Sleep Disorders, Restless Legs Syndrome, and Uremic Pruritus: Diagnosis and Treatment of Common Symptoms in Dialysis Patients

Maintenance dialysis patients experience a high burden of physical and emotional symptoms that directly affect their quality of life and health care utilization. In this review, we specifically highlight common troublesome symptoms affecting dialysis patients: insomnia, restless legs syndrome, and uremic pruritus. Epidemiology, pathophysiology, and evidence-based current treatment are reviewed with the goal of providing a guide for diagnosis and treatment. Finally, we identify multiple additional areas of further study needed to improve symptom management in dialysis patients.

The Cerebrovascular-Chronic Kidney Disease Connection: Perspectives and Mechanisms

Chronic kidney disease (CKD) is an independent risk factor for the development of cerebrovascular disease, particularly small vessel disease which can manifest in a variety of phenotypes ranging from lacunes to microbleeds. Small vessel disease likely contributes to cognitive dysfunction in the CKD population. Non-traditional risk factors for vascular injury in uremia include loss of calcification inhibitors, hyperphosphatemia, increased blood pressure variability, elastinolysis, platelet dysfunction, and chronic inflammation. In this review, we discuss the putative pathways by which these mechanisms may promote cerebrovascular disease and thus increase risk of future stroke in CKD patients.