How can we prevent intradialytic hypotension?:

Intradialytic Hypotension Pathophysiology and Therapy Update: Review and Update

BackgroundIntradialytic hypotension (IDH) is the most prevalent complication during hemodialysis (HD) sessions, affecting 10% to 12% of patients. It is linked with temporary ischemic stress in vital organs, increasing patient mortality. Various definitions of IDH have been proposed, and a strong correlation has been found between patient outcomes and the absolute lowest systolic blood pressure. The most probable underlying pathophysiology of IDH involves a reduced effective blood volume and decreased plasma tonicity. Optimizing the dialysis prescription and interventions during and after the dialysis session is sometimes effective for reducing IDH risk.Aim and MethodThis review discusses the pathophysiology, prevention, and therapy of IDH updates. To achieve this aim, Scopus, EMBASE, PubMed, Google, and Google Scholar were searched for articles published in the last two decades using phrases and keywords.ConclusionIntradialytic pathophysiology is ambiguous and unclear. The evidence for the effectiveness of the known therapies and maneuvers is limited. Ideally, IDH prevention should be the target; however, IDH management is sometimes needed. Different obstacles require further clinical research.

Visual Indicator for Intradialytic Hypotension Prediction Using Variation and Compensation of Heart Rate

BACKGROUND

To date, most intradialytic hypotension (IDH) studies have proposed technologies to comprehensively predict the occurrence of IDH using the patient's baseline information and ultrafiltration (UF) information, but it is difficult to apply the technologies while identifying the patient's condition in real time.

METHODS

In this study, we propose an IDH indicator that uses heart rate (HR) change information to identify the patient's condition in real time and visually shows whether IDH has occurred. The data used were collected from 40 dialysis patients in a clinical trial conducted in the Artificial Kidney Unit at Yeungnam University Medical Center, Korea, from 18 July to 29 November 2023.

RESULTS

The IDH indicator infers changes in the patient's blood pressure during dialysis by analyzing the upper and lower maximum HRs based on the real-time average HR. Medical staff can respond to IDH in real time by looking at the IDH indicator, which visually expresses changes in the patient's HR. In addition, we propose a multilayer perceptron structure that inputs upper and lower maximum HR information based on the average HR for the time interval accumulated in real time. In learning using 40 min of data up to 5 min before IDH occurred, models using two and five layers showed excellent performance, with accuracy of 88.6% and 85.2%, respectively.

CONCLUSIONS

By combining IDH visual indicators and the multi-layer perceptron method, medical staff can effectively respond to IDH in real time.

Effect of Pre- and Post-Dialysis Exercise on Functional Capacity Using Portable Ergometer in Chronic Kidney Disease Patients

OBJECTIVE

To assess whether performing exercises during hemodialysis reduces the risk of developing intradialytic hypotension and enhances exercise capacity in patients with chronic kidney disease.

METHODS

This study included patients aged ≥18 years undergoing hemodialysis. Participants performed exercises using a portable lower extremity ergometer during hemodialysis sessions for 3 weeks. Data regarding walking distance, knee strength, quality of life, fat-free mass, arterial pressure, blood pressure, heart rate, frequency of intradialytic hypotension, fatigue, and duration of hemodialysis were collected and analyzed.

RESULTS

Significant improvements in walking distance and knee strength were observed following the implementation of exercise training during hemodialysis. Although there was no significant reduction in the frequency of intradialytic hypotension, a decreasing trend was noted. Other parameters such as quality of life and fatigue did not show significant changes.

CONCLUSION

Using a portable ergometer during hemodialysis improved exercise capacity and knee strength in patients with chronic kidney disease. There was a trend toward reduced intradialytic hypotension, suggesting potential cardiovascular benefits. Further research with larger sample sizes is needed to confirm these findings.

Screening and Management of Coronary Artery Disease in Kidney Transplant Candidates

Cardiovascular disease (CVD) is a major cause of morbidity and mortality in patients with chronic kidney disease (CKD), especially in end-stage renal disease (ESRD) patients and during the first year after transplantation. For these reasons, and due to the shortage of organs available for transplant, it is of utmost importance to identify patients with a good life expectancy after transplant and minimize the transplant peri-operative risk. Various conditions, such as severe pulmonary diseases, recent myocardial infarction or stroke, and severe aorto-iliac atherosclerosis, need to be ruled out before adding a patient to the transplant waiting list. The effectiveness of systematic coronary artery disease (CAD) treatment before kidney transplant is still debated, and there is no universal screening protocol, not to mention that a nontailored screening could lead to unnecessary invasive procedures and delay or exclude some patients from transplantation. Despite the different clinical guidelines on CAD screening in kidney transplant candidates that exist, up to today, there is no worldwide universal protocol. This review summarizes the key points of cardiovascular risk assessment in renal transplant candidates and faces the role of noninvasive cardiovascular imaging tools and the impact of coronary revascularization versus best medical therapy before kidney transplant on a patient's cardiovascular outcome.

Dynamics of Plasma Refill Rate and Intradialytic Hypotension During Hemodialysis: Retrospective Cohort Study With Causal Methodology

Key Points

Directly studying plasma refill rate (PRR) during hemodialysis (HD) can offer insight into physiologic mechanisms that change throughout HD. PRR at the start and during HD is associated with intradialytic hypotension, independent of ultrafiltration rate. A rising PRR during HD may be an early indicator of compensatory mechanisms for impending circulatory instability.

Background

Attaining the optimal balance between achieving adequate volume removal while preserving organ perfusion is a challenge for patients receiving maintenance hemodialysis (HD). Current strategies to guide ultrafiltration are inadequate.

Methods

We developed an approach to calculate the plasma refill rate (PRR) throughout HD using hematocrit and ultrafiltration data in a retrospective cohort of patients receiving maintenance HD at 17 dialysis units from January 2017 to October 2019. We studied whether (1 ) PRR is associated with traditional risk factors for hemodynamic instability using logistic regression, (2 ) low starting PRR is associated with intradialytic hypotension (IDH) using Cox proportional hazard regression, and (3 ) time-varying PRR throughout HD is associated with hypotension using marginal structural modeling.

Results

During 180,319 HD sessions among 2554 patients, PRR had high within-patient and between-patient variability. Female sex and hypoalbuminemia were associated with low PRR at multiple time points during the first hour of HD. Low starting PRR has a higher hazard of IDH, whereas high starting PRR was protective (hazard ratio [HR], 1.26, 95% confidence interval [CI], 1.18 to 1.35 versus HR, 0.79, 95% CI, 0.73 to 0.85, respectively). However, when accounting for time-varying PRR and time-varying confounders, compared with a moderate PRR, while a consistently low PRR was associated with increased risk of hypotension (odds ratio [OR], 1.09, 95% CI, 1.02 to 1.16), a consistently high PRR had a stronger association with hypotension within the next 15 minutes (OR, 1.38, 95% CI, 1.30 to 1.45).

Conclusions

We present a straightforward technique to quantify plasma refill that could easily integrate with devices that monitor hematocrit during HD. Our study highlights how examining patterns of plasma refill may enhance our understanding of circulatory changes during HD, an important step to understand how current technology might be used to improve hemodynamic instability.

Acute intermittent hemodialysis management in childhood: A single center experience

INTRODUCTION

The objective of this study was to determine the common indications of acute intermittent hemodialysis (IHD) treatment in childhood and to assess the characteristics of the procedure, complications, and prognosis.

METHODS

The study included 102 patients aged between 0 and 18 years, who had been acute dialysis indication and treated with IHD.

RESULTS

In terms of acute kidney injury (AKI) etiology, glomerular diseases were prominent in 56% of the patients, and 8.6% of surviving patients progressed to end-stage renal disease. Regarding the cause of AKI, having the glomerular disease was determined to be directly associated (p = 0.01) with the risk of progression to chronic kidney disease (CKD) regardless of age, gender, onset time of renal replacement therapy.

CONCLUSION

Glomerular diseases were the most common in AKI etiology and were associated with the progression to CKD, independent of age, gender and the time of IHD onset in our study.

Management of intradialytic hypertension: current evidence and future perspectives

Intradialytic hypertension (IDH), that is, a paradoxical rise in blood pressure (BP) during or immediately after a hemodialysis session, affects approximately 10-15% of the hemodialysis population. It is currently recognized as a phenomenon of major clinical significance as recent studies have shown that BP elevation extends to the whole interdialytic interval and associates with increased cardiovascular and all-cause mortality. The pathophysiology of IDH is complex involving volume and sodium overload, endothelial dysfunction, excess renin-angiotensin-aldosterone system and sympathetic nervous system activation, and other mechanisms. For several years, there was a scarcity of studies regarding IDH treatment; recently, however, several attempts to examine the effect of nonpharmacological and pharmacological measures on BP levels in IDH are made. This review attempts to summarize this latest evidence in the field of management of IDH and discuss areas for future research.

Multilayer Perceptron-Based Real-Time Intradialytic Hypotension Prediction Using Patient Baseline Information and Heart-Rate Variation

Intradialytic hypotension (IDH) is a common side effect that occurs during hemodialysis and poses a great risk for dialysis patients. Many studies have been conducted so far to predict IDH, but most of these could not be applied in real-time because they used only underlying patient information or static patient disease information. In this study, we propose a multilayer perceptron (MP)-based IDH prediction model using heart rate (HR) information corresponding to time-series information and static data of patients. This study aimed to validate whether HR differences and HR slope information affect real-time IDH prediction in patients undergoing hemodialysis. Clinical data were collected from 80 hemodialysis patients from 9 September to 17 October 2020, in the artificial kidney room at Yeungnam University Medical Center (YUMC), Daegu, South Korea. The patients typically underwent hemodialysis 12 times during this period, 1 to 2 h per session. Therefore, the HR difference and HR slope information within up to 1 h before IDH occurrence were used as time-series input data for the MP model. Among the MP models using the number and data length of different hidden layers, the model using 60 min of data before the occurrence of two layers and IDH showed maximum performance, with an accuracy of 81.5%, a true positive rate of 73.8%, and positive predictive value of 87.3%. This study aimed to predict IDH in real-time by continuously supplying HR information to MP models along with static data such as age, diabetes, hypertension, and ultrafiltration. The current MP model was implemented using relatively limited parameters; however, its performance may be further improved by adding additional parameters in the future, further enabling real-time IDH prediction to play a supporting role for medical staff.

The importance of muscle mass in predicting intradialytic hypotension in patients undergoing maintenance hemodialysis

Background

Patients undergoing hemodialysis are susceptible to sarcopenia. As intracellular reservoirs of water, skeletal muscles are important contributors to intradialytic hypotension. This study was designed to determine the role of skeletal muscle mass in intradialytic hypotension.

Methods

In a cross-sectional study, the body composition of 177 patients was measured immediately after hemodialysis using bioelectrical impedance analysis. The parameters measured were skeletal muscle mass, intracellular and extracellular water contents, total body water, and cell-membrane functionality (in phase angle at 50 kHz). Data from laboratory tests, chest radiography, measurements of handgrip strength and mid-arm circumference, and questionnaires were collected. The main outcome was intradialytic hypotension, defined as more than two episodes of hypotension (systolic blood pressure of <90 mmHg) with intervention over the 3 months following enrollment. Logistic regression models including each parameter related to sarcopenia were compared with a clinical model.

Results

Patients with a low ratio of skeletal muscle mass to dry body weight (SMM/WT) had a higher rate of intradialytic hypotension (41%). Most low-SMM/WT patients were female, obese, diabetic, and had a lower handgrip strength compared with the other patients. In the high-SMM/WT group, the risk of intradialytic hypotension was lower, with an odds ratio of 0.08 (95% confidence interval [CI], 0.02-0.28) and adjusted odds ratio of 0.06 (95% CI, 0.01-0.29).

Conclusion

Measurement and maintenance of skeletal muscle can help prevent intradialytic hypotension in frail patients undergoing hemodialysis.

Efficacy and safety of furosemide for prevention of intradialytic hypotension in haemodialysis patients: protocol for a multicentre randomised controlled trial

INTRODUCTION

Intradialytic hypotension (IDH) is a frequent and serious complication of maintaining haemodialysis (HD) patients and associated with subsequent cardiovascular events and higher mortality. Furosemide is commonly used in non-dialysis chronic kidney disease patients and can effectively manage the volume and blood pressure. However, these agents are often discontinued on initiation of dialysis. Two large observational studies have demonstrated that furosemide can lower the rate of IDH episodes. However, there is still no randomised controlled trial (RCT) to investigate the efficacy and safety of furosemide for prevention of IDH in HD patients. The purpose of this study was to assess the efficacy of furosemide in reducing IDH in HD patients with residual renal function.

METHODS AND ANALYSIS

A two-arm, parallel, multicente RCT will be conducted at 12 hospitals in China. An estimated sample of 560 HD patients will be recruited. Eligible patients will be randomly assigned to treatment group (patients receive oral furosemide 80 mg/day; after a 2-week treatment, if their urine volume is less than 400 mL/day, the dose of furosemide is adjusted to 160 mg/day) and blank control group via a central randomisation system using 1:1 ratio. The primary outcome is the occurrence of IDH. Outcome assessors and data analysts will be blinded and participants will be asked not to reveal their allocation to assessors. The outcome analyses will be performed both on the intention-to-treat, which includes all patients randomised, and per-protocol population, which includes eligible patients who adhere to the planned treatment and follow-ups.

ETHICS AND DISSEMINATION

The trial protocol has been approved by the Biomedical Research Ethics Committee of West China Hospital of Sichuan University (2019.385)Results will be presented at national and international conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR2000039724.

Intravenous Albumin for Mitigating Hypotension and Augmenting Ultrafiltration during Kidney Replacement Therapy

Among its many functions, owing to its oversized effect on colloid oncotic pressure, intravascular albumin helps preserve the effective circulatory volume. Hypoalbuminemia is common in hospitalized patients and is found especially frequently in patients who require KRT either for AKI or as maintenance hemodialysis. In such patients, hypoalbuminemia is strongly associated with morbidity, intradialytic hypotension, and mortality. Intravenous albumin may be administered in an effort to prevent or treat hypotension or to augment fluid removal, but this practice is controversial. Theoretically, intravenous albumin administration might prevent or treat hypotension by promoting plasma refilling in response to ultrafiltration. However, clinical trials have demonstrated that albumin administration is not nearly as effective a volume expander as might be assumed according to its oncotic properties. Although intravenous albumin is generally considered to be safe, it is also very expensive. In addition, there are potential risks to using it to prevent or treat intradialytic hypotension. Some recent studies have suggested that hyperoncotic albumin solutions may precipitate or worsen AKI in patients with sepsis or shock; however, the overall evidence supporting this effect is weak. In this review, we explore the theoretical benefits and risks of using intravenous albumin to mitigate intradialytic hypotension and/or enhance ultrafiltration and summarize the current evidence relating to this practice. This includes studies relevant to its use in patients on maintenance hemodialysis and critically ill patients with AKI who require KRT in the intensive care unit. Despite evidence of its frequent use and high costs, at present, there are minimal data that support the routine use of intravenous albumin during KRT. As such, adequately powered trials to evaluate the efficacy of intravenous albumin in this setting are clearly needed.

Relationship of a food intake during hemodialysis and symptomatic intradialytic hypotension

INTRODUCTION

Intradialytic hypotension is the most common complication during hemodialysis and is associated with increased cardiovascular disease, mortality, and overall hospital admissions. We analyzed the influence of food intake during hemodialysis on intradialytic hypotension.

METHODS

A total of 105 patients treated with chronic hemodialysis were observed for 8 weeks-4 weeks with a meal during hemodialysis and 4 weeks without a meal.

FINDINGS

A statistically significant decrease of hypotensive events (p < 0.001) and cramping episodes (p = 0.035) was observed during a 4-week period without a meal. Patients who were particularly susceptible to intradialytic hypotension were those who were diabetic, had low urinary excretion, and were treated with hemodialysis for a long time. On a follow up, there was a significant increase in serum albumin after 3 months (p = 0.01) and 6 months (p = 0.036) despite meal withdrawal during hemodialysis.

DISCUSSION

Fasting during hemodialysis may cause a significantly lower frequency of intradialytic hypotension and cramping episodes without affecting the nutritional status.

Effects of diuretics on intradialytic hypotension in maintenance dialysis patients: a systematic review and meta-analysis

PURPOSE

Intradialytic hypotension (IDH) is a serious complication in dialysis patients. Diuretics might reduce the incidence of IDH by decreasing ultrafiltration. However, the effect of diuretics on IDH in maintenance dialysis patients is still unclear.

METHODS

We searched Medline, Embase, the Cochrane Library, China National Knowledge Infrastructure and clinical trials registries from 1945 to May 2019. Randomized controlled trials (RCTs) or observational studies about IDH in maintenance dialysis with diuretics were included.

RESULTS

Seven studies including 28,226 patients were included, of which 4 were RCTs involving mineralocorticoid receptor antagonists (MRAs) and 3 were observational studies involving loop diuretics. There was a trend that a lower incidence rate of IDH in maintenance dialysis patients who used loop diuretics than control, although the result was not statistically significant (OR 0.65, 95% CI 0.34-1.22, P = 0.18). Similarly, lower incidence rate of all-cause mortality (OR 0.92, 95% CI 0.87-0.99; P = 0.02) and cardiovascular (CV) mortality (OR 0.86, 95% CI 0.75-0.99, P = 0.03) in dialysis patients who used loop diuretics than control. On the contrary, there were no significant difference in the incidence of IDH (OR 1.35, 95% CI 0.78-2.34, P = 0.29) and all-cause mortality (OR 0.73, 95% CI 0.26-2.01; P = 0.54) and CV mortality (OR 0.57, 95% CI 0.14-2.25; P = 0.42) in maintenance dialysis patients who used MRAs compared with control.

CONCLUSION

Loop diuretics, but not MRAs, might have a potential benefit to reduce the incidence rate of IDH, all-cause mortality and CV mortality. More high-quality studies are needed to strengthen the arguments.

Serum Phosphorus Levels are Associated with Intradialytic Hypotension in Hemodialysis Patients

BACKGROUND

Intradialytic hypotension (IDH) is a common serious complication in hemodialysis (HD) patients. Hyperphosphatemia is also common in HD patients and promotes vascular calcification. Given the association between vascular calcification and IDH, we investigated the association between IDH and serum phosphorus in HD patients.

METHODS

We enrolled 173 patients who received HD for 3 months or more. IDH was defined as a nadir systolic blood pressure (SBP) <90 mm Hg or as a decrease in SBP ≥20 mm Hg or a decrease in mean arterial pressure by 10 mm Hg with the occurrence of hypotension-related symptoms requiring intervention. Serum phosphorus levels were analyzed both as a continuous variable and as a categorical variable.

RESULTS

IDH occurred in 40 (23.1%) of the 173 patients. The mean phosphorus level was 4.9 mg/dL. A 1 mg/dL higher serum phosphorus resulted in a 2.1-fold greater odds of IDH. The fully adjusted odds ratio (OR) and 95% confidence interval (CI) were 2.11 (1.48-3.01). High categorized phosphorus levels were also associated with IDH. The highest tertile of serum phosphorus was associated with 6.5-fold greater odds of developing IDH compared to the referent group (the middle tertile of serum phosphorus, 4.0-<5.3 mg/dL); the fully adjusted OR (95% CIs) were 6.53 (2.23-19.09). In subgroup analyses, diabetes and pre-dialysis SBP modified the association between IDH and phosphorus levels, with a more pronounced association in diabetic patients and pre-dialysis SBP ≥140 mm Hg.

CONCLUSION

In HD patients, higher phosphorus levels were associated with an increased occurrence of IDH.

Hemodialysis crossover study using a relative blood volume change-guided ultrafiltration control compared with standard hemodialysis: the BV-UFC study

Background

It has been difficult to sufficiently achieve body-fluid management using blood volume (BV) monitor during hemodialysis (HD) with constant ultrafiltration (UF) rate. Recently, a relative BV change-guided UF control (BV-UFC) system was developed by combining the concepts of an automatic feedback system that could control the UF rate and profile with real- time monitoring of relative changes in BV (%ΔBV). However, this system has limited application in the clinical setting. Therefore, in this study, we aimed to perform the crossover study on HD with BV-UFC compared to standard HD in terms of hemodynamic stability during HD.

Methods

Forty-eight patients entered an 8-week crossover period of standard HD or HD with BV-UFC. Prevalence of intradialytic hypotension (IDH) as a primary outcome and changes in blood pressure (BP), differences in %ΔBV, and achievement of the target ultrafiltration volume as secondary outcomes were compared. IDH was defined as a reduction in systolic BP ≥20 mmHg from the baseline value at 10 min after HD initiation.

Results

No significant differences were found in the prevalence of IDH, frequency of intervention for symptomatic IDH, and achievement of the target ultrafiltration volume between the groups. The %ΔBV was significantly fewer (-12.1 ± 4.8% vs. -14.4 ± 5.2%, p <0.001) in the HD with BV-UFC than that in the standard HD.

Conclusions

HD with BV-UFC did not reduce the prevalence of IDH compared with standard HD. The relief of a relative BV reduction at the end of HD may be beneficial in patients undergoing HD with BV-UFC.

Trial Registration

UMIN, UMIN000024670. Registered on December 1, 2016.

Monitoring for intradialytic hypotension: An audit of nursing practice

BACKGROUND

Intradialytic hypotension (IDH) is one of the most common complications associated with haemodialysis (HD), yet the frequency of patient assessment by nurses varies in practice. We sought to measure the frequency of nursing assessments before, during and after HD and to identify any predictors of IDH.

OBJECTIVES

To audit the frequency, nursing management and contributing factors of IDH.

DESIGN

A prospective clinical audit was undertaken over 4 weeks.

PARTICIPANTS

Nurses completed audit sheets on 132 patients at three chronic HD units.

MEASUREMENTS

The audit tool consisted of 34 questions related to demographics, HD prescription, frequency of monitoring and nursing interventions.

RESULTS

A total of 1584 sessions were performed with 876 (55.3%) audits returned, of which 452 were useable. There were 74 actual episodes of IDH, and a further 72 potential episodes may have been prevented due to nursing intervention. Most nurses reported assessing patients before starting HD and as required before an actual or potential IDH event (n = 85; 63%); few hourly assessments were performed. Predictors of IDH were systolic blood pressure ≤140 mmHg, having more than four comorbidities, dialysate temperature > 36°C, calcium < 1.3 mmol/L and a shorter dialysis session (3.0-4.5 h). These predictors explained 14.1% of the variance in hypotensive episodes during HD.

CONCLUSION

This clinical audit highlighted the importance of assessing blood pressure trends during HD to preemptively intervene before IDH developing. The audit has resulted in a practice change to hourly assessments. Follow-up audits of practice should occur.

Eating during the Hemodialysis Session: A Practice Improving Nutritional Status or a Risk Factor for Intradialytic Hypotension and Reduced Dialysis Adequacy?

Historically, eating during the hemodialysis treatment has been associated with increased risk for adverse intradialytic symptoms and events, risks that have resulted in the implementation of restrictive in-center nutrition policies. Recent studies, however, have recorded a shift in clinical practice with a higher proportion of physicians following the view that administration of intradialytic meals and supplements represents a simple and effective approach to enhance caloric intake and improve nutritional status among patients on hemodialysis. This shift towards less restrictive in-center nutrition practices is mainly supported by evidence from observational studies associating intradialytic nutritional supplementation with improvements in protein-energy wasting, inflammatory state, and health-related quality of life. In sharp contrast, earlier and recent interventional studies have documented that feeding during the hemodialysis treatment provokes a rapid postprandial decline in blood pressure and raises the incidence of symptomatic intradialytic hypotension. Furthermore, other studies have shown that postprandial redistribution in intravascular volume and enhanced blood supply to the gastrointestinal circulation may interfere with the adequacy of the delivered hemodialysis. Those who defend the position that intradialytic nutritional support is beneficial do not dispute the physiology of postprandial hemodynamic response, but they argue against its clinical significance. In this article, we provide an overview of studies that explored the effect of eating during the hemodialysis treatment on intradialytic hemodynamic stability and adequacy of the delivered hemodialysis. We reason that these risks have important clinical implications that are not counteracted by anticipated benefits of this strategy on caloric intake and nutritional status.

Dataset supporting blood pressure prediction for the management of chronic hemodialysis

Hemodialysis (HD) is a treatment given to patients with renal failure. Notable treatment-related complications include hypotension, cramps, insufficient blood flow, and arrhythmia. Most complications are associated with unstable blood pressure during HD. Physicians are devoted to seeking solutions to prevent or lower the incidence of possible complications. With advances in technology, big data have been obtained in various medical fields. The accumulated dialysis records in each HD session can be gathered to obtain big HD data with the potential to assist HD staff in increasing patient wellbeing. We generated a large stream of HD parameters collected from dialysis equipment associated with the Vital Info Portal gateway and correlated with the demographic data stored in the hospital information system from each HD session. We expect that the application of HD big data will greatly assist HD staff in treating intradialytic hypotension, setting optimal dialysate parameters, and even developing an intelligent early-warning system as well as providing individualized suggestions regarding dialysis settings in the future.

Feeding during dialysis-risks and uncertainties

Allowing dialysis patients to eat during the treatment is controversial. It is, therefore, no surprise that practices and policies with respect to intradialytic food consumption vary considerably from unit to unit and from country to country. Those who defend the position of feeding during dialysis reason that intradialytic meals offer a supervised and effective therapy for protein-energy wasting. Those who take the opposite view argue that intradialytic food intake should be avoided for the following three reasons. First, interventional studies show that eating during dialysis causes a clinically significant reduction in systemic blood pressure during the postprandial period and elevates the risk of symptomatic intradialytic hypotension; the latter is associated with increased mortality risk. Second, clinical studies have shown that eating during dialysis interferes with the adequacy of the delivered dialysis, whereas eating 2-3 h before the dialysis session has no impact on the efficiency of the subsequent dialysis treatment. And third, randomized studies show that eating during dialysis focus on the positive outcomes but do not adequately balance this potential benefit against the risk of intradialytic hemodynamic instability and poor quality of delivered dialysis. Even after half a century of providing long-term dialysis, definitive randomized trials that balance risks and benefits of eating during dialysis are missing. These knowledge gaps require randomized trials. Since there is a real possibility of harm with eating during dialysis, we caution that instead of encouraging the widespread use of intradialytic meals, practices and policies should focus on adequate nutrient intake during the interdialytic interval.

Saline versus albumin fluid for extracorporeal removal with slow low-efficiency dialysis (SAFER-SLED): study protocol for a pilot trial

Background

Critically ill patients frequently develop acute kidney injury that necessitates renal replacement therapy (RRT). At some centers, critically ill patients who are hemodynamically unstable and require RRT are treated with slow low-efficiency dialysis (SLED). Unfortunately, hypotension is a frequent complication that occurs during SLED treatments and may limit the recovery of kidney function. Hypotension may also limit the amount of fluid that can be removed by ultrafiltration with SLED. Fluid overload can be exacerbated as a consequence, and fluid overload is associated with increased mortality.

Occasionally, intravenous albumin fluid is given to prevent or treat low blood pressure during SLED. The intent of doing so is to increase the colloid oncotic pressure in the circulation to draw in extravascular fluid, increase the blood pressure, and enable more aggressive fluid removal with ultrafiltration. Nonetheless, there is little evidence to support this practice and theoretical reasons why it may not be especially effective at augmenting fluid removal in critically ill patients. At the same time, albumin fluid is expensive.

As such, we present a protocol for a study to assess the feasibility of a randomized controlled trial evaluating the use of albumin fluid versus saline in critically ill patients receiving SLED.

Methods

This study is a single-center, double-blind, and randomized controlled pilot trial with two parallel arms. It involves randomly assigning patients receiving SLED treatment in the ICU to receive either albumin (25%) boluses or normal saline fluid boluses (placebo) to prevent and treat low blood pressure.

Discussion

The results of this pilot trial will help with planning a larger trial comparing the efficacy of the interventions in achieving fluid removal in critically ill patients with AKI on SLED. They will establish whether enough participants would participate in a larger study and accept the study procedures.

Trial registration

This trial is registered on ClinicalTrials.gov Identifier NCT03665311, registered on September 11, 2018.

Electronic supplementary material

The online version of this article (10.1186/s40814-019-0460-3) contains supplementary material, which is available to authorized users.

Nocturnal hemodialysis: improved quality of life and patient outcomes

Conventional hemodialysis is associated with high morbidity and mortality rates, as well as a reduced quality of life. There is a growing interest in the provision of more intensive hemodialysis, due to associated benefits in terms of reduced cardiovascular morbidity, better regulation of mineral metabolism, as well as its impact on quality of life measures, fertility, and sleep. Nocturnal hemodialysis, both in center and at home, allows the delivery of more intensive hemodialysis. This review discusses the benefits of nocturnal hemodialysis and evaluates the evidence based on available literature.

Predicting intradialytic hypotension using heart rate variability

This study aimed to identify whether a new method using heart rate variability (HRV) could predict intradialytic hypotension (IDH) for one month in advance for patients undergoing prevalent hemodialysis. A total 71 patients were enrolled, and baseline clinical characteristics and laboratory results were collected when HRV was measured, then, the frequency of IDH was collected during the observation period. HRV parameters included heart rate, R-R interval, the standard deviation of N-N interval, the square root of the mean squared differences of successive NN intervals, very low frequency, low frequency, high frequency, total power, and low frequency/high frequency ratio. During the one-month observation period, 28 patients experienced 85 cases of IDH (10.0% of a total 852 dialysis sessions). Among the clinical and laboratory parameters, ultrafiltration rate, prior history of diabetes, coronary artery disease, or congestive heart failure, age, intact parathyroid hormone level, and history of antihypertensive drug use were integrated into the multivariate model, referred to as a basic model, which showed significant ability to predict IDH (the area-under-curve [AUC], 0.726; p = 0.002). In HRV parameters, changes between the early and middle phases of hemodialysis (referred to Δ) were identified as significant independent variables. New models were built from the combination of Δ values with the basic model. Among them, a model with the highest AUC value (AUC, 804; p < 0.001) was compared to the basic model and demonstrated improved performance when HRV parameters were used (p = 0.049). Based on our results, it is possible that future IDH might be predicted more accurately using HRV.

The Effect of Mechanically-Generated Vibrations on the Efficacy of Hemodialysis; Assessment of Patients' Safety: Preliminary Reports

Muscle activity during a hemodialysis procedure improves its efficacy. We have formulated a hypothesis that vibrations generated by a specially-designed dialysis chair can, the same as physical exercise, affect the filtering of various fluids between fluid spaces during the hemodialysis procedure. This prospective and interventional study included 21 dialyzed patients. During a single dialysis session, each patient used a prototype device with the working name “vibrating chair”. The chair’s drive used a low-power cage induction motor, which, along with the worm gear motor, was a part of the low-frequency (3.14 Hz) vibration-generating assembly with an amplitude of 4 mm. Tests and measurements were performed before and after the vibration dialysis. After a single hemodialysis session including five 3-min cycles of vibrations, an increase in Kt/V in relation to non-vibration Kt/V (1.53±0.26 vs. 1.62±0.23) was seen. Urea reduction ratio increased significantly (0.73±0.03 vs. 0.75±0.03). A significant increase in systolic blood pressure was observed between the first and the third measurement (146±18 vs. 156±24). The use of a chair generating low-frequency vibrations increased dialysis adequacy; furthermore, it seems an acceptable and safe alternative to intradialytic exercise.

Prescribing Hemodialysis or Hemodiafiltration: When One Size Does Not Fit All the Proposal of a Personalized Approach Based on Comorbidity and Nutritional Status

There is no simple way to prescribe hemodialysis. Changes in the dialysis population, improvements in dialysis techniques, and different attitudes towards the initiation of dialysis have influenced treatment goals and, consequently, dialysis prescription. However, in clinical practice prescription of dialysis still often follows a "one size fits all" rule, and there is no agreed distinction between treatment goals for the younger, lower-risk population, and for older, high comorbidity patients. In the younger dialysis population, efficiency is our main goal, as assessed by the demonstrated close relationship between depuration (tested by kinetic adequacy) and survival. In the ageing dialysis population, tolerance is probably a better objective: "good dialysis" should allow the patient to attain a stable metabolic balance with minimal dialysis-related morbidity. We would like therefore to open the discussion on a personalized approach to dialysis prescription, focused on efficiency in younger patients and on tolerance in older ones, based on life expectancy, comorbidity, residual kidney function, and nutritional status, with particular attention placed on elderly, high-comorbidity populations, such as the ones presently treated in most European centers. Prescription of dialysis includes reaching decisions on the following elements: dialysis modality (hemodialysis (HD) or hemodiafiltration (HDF)); type of membrane (permeability, surface); and the frequency and duration of sessions. Blood and dialysate flow, anticoagulation, and reinfusion (in HDF) are also briefly discussed. The approach described in this concept paper was developed considering the following items: nutritional markers and integrated scores (albumin, pre-albumin, cholesterol; body size, Body Mass Index (BMI), Malnutrition Inflammation Score (MIS), and Subjective Global Assessment (SGA)); life expectancy (age, comorbidity (Charlson Index), and dialysis vintage); kinetic goals (Kt/V, normalized protein catabolic rate (n-PCR), calcium phosphate, parathyroid hormone (PTH), beta-2 microglobulin); technical aspects including vascular access (fistula versus catheter, degree of functionality); residual kidney function and weight gain; and dialysis tolerance (intradialytic hypotension, post-dialysis fatigue, and subjective evaluation of the effect of dialysis on quality of life). In the era of personalized medicine, we hope the approach described in this concept paper, which requires validation but has the merit of providing innovation, may be a first step towards raising attention on this issue and will be of help in guiding dialysis choices that exploit the extraordinary potential of the present dialysis "menu".

Does the plasma refilling coefficient change during hemodialysis sessions?

The filtration coefficient in the Starling equation is an important determinant of plasma refilling during hemodialysis. A method for calculating from clinical data an estimate of the filtration coefficient, called the refilling coefficient, was proposed in the past. The assumption behind this method was that the only drive for refilling is the increase in plasma oncotic pressure, and the remaining Starling forces have negligible effect. The refilling coefficient was observed to decrease during hemodialysis, and this was interpreted as a change in the filtration coefficient. The purpose of our study was providing an alternative explanation for the behavior of the refilling coefficient and, using clinical data and mathematical modeling, to predict the values of the immeasurable Starling forces and provide the theoretical basis for the interpretation of the refilling coefficient as the filtration coefficient. Blood volume and bioimpedance data from 23 patients undergoing hemodialysis were used to calculate the refilling coefficient according to the original formulation and to fit a two-compartment model of protein and fluid transport. The changes in the other Starling forces were non-negligible, ranging from 19% to 60% of plasma oncotic pressure. The results showed that the decrease observed in the refilling coefficient is likely caused by neglecting important changes in the Starling forces while deriving the equation for the refilling coefficient. When these Starling forces were taken into account, constant filtration coefficient and dynamic refilling coefficient provided an equivalent description of the data in most cases. However, this was not true for a subgroup of sessions, which suggests that additional factors may also be responsible for the observed decrease in the refilling coefficient.

Treatment of intradialytic hypotension with an herbal acupoint therapy in hemodialysis patients: A randomized pilot study

OBJECTIVE

Hypotension during hemodialysis (HD) is the most common complication that negatively affects the quality of life of patients. The objective of the current study was to evaluate the preliminary efficacy and safety of herbal acupoint therapy (HAT) for intradialytic hypotension (IDH).

METHODS

A randomized, placebo-controlled trial was performed in 32 HD patients to determine whether HAT was more effective than a sham treatment for the treatment of IDH. The outcomes were frequency of IDH episodes and number of nursing interventions during HD sessions, pre- and post-dialysis BP, subjective change in fatigue as measured by the Visual Analogue Scale (VAS), and recovery time from fatigue after dialysis at the 0th and 4th week. Data analyses were performed using per-protocol population.

RESULTS

In all, 27 patients (84%) completed the entire study. At the end of the intervention, the patients in the HAT group were found to have a significantly lower frequency of IDH episodes, fewer nursing interventions, a lower intervention failure rate, and earlier discontinuation of dialysis than those in the sham group (p < .05). The improvement in degree of fatigue (p = .001) was greater and recovery time from fatigue after dialysis (p = .03) was shorter in the group treated with HAT than in the sham group. HAT was safe, with 2 withdrawal cases due to local erythema caused by the patch.

CONCLUSIONS

HAT appears to be safe and efficacious for improving IDH-related symptoms and intervention in HD patients. Larger studies are needed to confirm the benefit of this technique for IDH.

Hemodialysis-induced cardiovascular disease

More than half of all deaths among end stage renal disease (ESRD) patients are due to cardiovascular disease (CVD). Cardiovascular changes secondary to renal dysfunction, including fluid overload, uremic cardiomyopathy, secondary hyperparathyroidism, anemia, altered lipid metabolism, and accumulation of gut microbiota-derived uremic toxins like trimethylamine N-oxidase, contribute to the high risk for CVD in the ESRD population. In addition, conventional hemodialysis (HD) itself poses myocardial stress and injury on the already compromised cardiovascular system in uremic patients. This review will provide an overview of cardiovascular changes in chronic kidney disease and ESRD, a description of reported mechanisms for HD-induced myocardial injury, comparison of HD with other treatment modalities in the context of CVD, and possible management strategies.

Prevalence and risk factors of intra-dialytic hypotension: a 5 year retrospective report from a single Nigerian Centre

INTRODUCTION

Intra-dialytic hypotension (IDH) is a common complication of haemodialysis that impacts negatively on the patient's quality of life and can induce serious cardiovascular events.

METHODS

Records of all adults who had haemodialysis treatments from Jan 2012-Jan 2016 were reviewed. Socio-demographic data, health status of patient, aetiology of renal disease, clinical and biochemical parameters such as systolic and diastolic blood pressures (SBP and DBP), packed cell volume, were collated using Microsoft Excel.

RESULTS

The overall prevalence of intra-dialytic hypotension was 8.6%. Of all haemodialysis patients, 45.7% experienced a drop in SBP > 20mmHg, 28.5% required nurses' intervention and 8.6% had symptoms. Diagnosis of obstructive nephropathy (OR: 3.1, CI:1.43-6.60, p = < 0.004) and sepsis (OR: 3.57, CI: 1.31- 9.75, P = 0.013) increased the odds of experiencing IDH. Only 5% of patients with predialysis SBP < 100mmHg developed IDH (OR: 0.12, CI: 0.02-0.93, P = 0.04).

CONCLUSION

IDH was common among the patients studied. It was more prevalent among patients with obstructive nephropathy and sepsis; however other traditional risk factors of IDH such as older age and anaemia, were not found to be significantly associated with IDH. Surprisingly, prevalence of IDH was significantly less among patients with pre-dialysis hypotension compared to those without.

Sodium modelling to reduce intradialytic hypotension during haemodialysis for acute kidney injury in the intensive care unit

AIM

Intradialytic hypotension often complicates haemodialysis for patients with acute kidney injury (AKI) and may impact renal recovery. Sodium modelling is sometimes used as prophylaxis against intradialytic hypotension in the chronic haemodialysis population, but there is little evidence for its use among critically ill patients with AKI.

METHODS

A retrospective cohort with AKI requiring intermittent haemodialysis in the intensive care unit from 2001 to 2008 was used to study the association of prophylactic sodium modelling and multiple outcomes. Outcomes included a composite of in-hospital death or dialysis dependence at hospital discharge, as well as intradialytic hypotension, ultrafiltration goal achievement and net ultrafiltration volume. Associations were estimated using logistic regression, mixed linear models and generalized estimating equations adjusting for demographic and clinical characteristics.

RESULTS

One hundred and ninety-one individuals who underwent 892 sessions were identified; sodium modelling was prescribed in 27.1% of the sessions. In adjusted analyses, sodium modelling was not significantly associated with intradialytic hypotension (P = 0.67) or with the ultrafiltration goal achievement (P = 0.06). Sodium modelling during the first dialysis session was numerically associated with lower risk for the composite of in-hospital death or dialysis dependence: adjusted odds ratio (95% confidence interval) 0.39 (0.15-1.02; P = 0.06); however, this association did not reach statistical significance.

CONCLUSION

We did not observe statistically significant associations between sodium modelling and improved outcomes among AKI patients receiving intermittent dialysis in the intensive care unit. However, suggestive findings warrant further study.

Diagnosis, Treatment, and Prevention of Hemodialysis Emergencies

Given the high comorbidity in patients on hemodialysis and the complexity of the dialysis treatment, it is remarkable how rarely a life-threatening complication occurs during dialysis. The low rate of dialysis emergencies can be attributed to numerous safety features in modern dialysis machines; meticulous treatment and testing of the dialysate solution to prevent exposure to trace elements, toxins, and pathogens; adherence to detailed treatment protocols; and extensive training of dialysis staff to handle medical emergencies. Most hemodialysis emergencies can be attributed to human error. A smaller number are due to rare idiosyncratic reactions. In this review, we highlight major emergencies that may occur during hemodialysis treatments, describe their pathogenesis, offer measures to minimize them, and provide specific interventions to prevent catastrophic consequences on the rare occasions when such emergencies arise. These emergencies include dialysis disequilibrium syndrome, venous air embolism, hemolysis, venous needle dislodgement, vascular access hemorrhage, major allergic reactions to the dialyzer or treatment medications, and disruption or contamination of the dialysis water system. Finally, we describe root cause analysis after a dialysis emergency has occurred to prevent a future recurrence.

Intra-dialytic blood oxygen saturation (SO2): association with dialysis hypotension (the SOGLIA Study)

BACKGROUND

Intradialytic hypotension (IDH) has a dramatic impact on the main outcomes of dialysis patients. Early warning of hemodynamic worsening during dialysis would enable preventive measures to be taken. Blood oxygen saturation (SO₂) is used for hemodynamic monitoring in the critical care setting and may provide useful information about IDH onset.

AIM

To evaluate whether short- and medium-term variations in the SO₂ signal (ST-SO_2var, MT-SO_2var,) during dialysis are a predictor of IDH.

METHODS

In this 3-month observational cohort study, 51 hypotension-prone chronic hemodialysis (HD) patients, with vascular access by arteriovenous fistula (AVF) or central venous catheter (CVC), were enrolled. Continuous non-invasive blood SO₂ was monitored (fc = 0.2 Hz) by an optical sensor on the arterial line of the extracorporeal circulation; blood pressure (every 30 min), symptoms and their time of appearance were noted. Predictive power of IDH was expressed by the area under curve (AUC) sensitivity and specificity based on intradialytic variations in SO₂.

RESULTS

A total of 1290 HD sessions were analyzed. Overall, off-line ST-SO_2var analysis proved able to correctly predict IDH in 67 % of the sessions where IDH occurred. The best predictive performance was found in the presence of highly arterialized AVF (SO₂ > 95 %) (75 % sensitivity; AUC 0.825; p < 0.05). On the contrary, in sessions with CVC, IDH prediction proved more efficient by MT-SO_2var (AUC 0.575; p = 0.01).

CONCLUSIONS

Intradialytic SO₂ variability could be a valid parameter to detect in advance the hemodynamic worsening that precedes IDH. Appropriate timely intervention could help prevent IDH onset.

Study protocol for a single-blind, placebo-controlled randomised trial of Tianjiu effects in patients with intradialytic hypotension

INTRODUCTION

Intradialytic hypotension (IDH) is the most frequent complication of haemodialysis (HD) and may contribute to cardiovascular events and high mortality. The aetiology of IDH is multifactorial; therefore, it remains a challenging problem in the management of patients with HD. Since the application of Tianjiu at specific points can influence haemodynamics, we hypothesise that Tianjiu therapy at the traditionally used meridian points will reduce the severity of hypotension in patients who undergo HD.

METHODS/ANALYSIS

In this clinical trial, eligible patients with IDH will be divided randomly and equally into a Tianjiu group and a control group for 4 weeks. In the Tianjiu group, the patients will have Tianjiu applied at three points (conception vessel 4, and bilateral kidney 1) during each HD session. In the control group, patients will have clay patches applied in the same way as those in the Tianjiu treatment group. Both groups will be followed up for 2 weeks. The primary outcome measure will be the percentage of target ultrafiltration achieved, defined as the actual ultrafiltration volume divided by the target ultrafiltration volume. Secondary outcome measures, including frequency of IDH episodes and number of nursing interventions during HD sessions, predialysis and postdialysis blood pressure (BP), patient's participative assessment of the degree of fatigue after dialysis (scale from 0, not at all, to 10, extremely), and recovery time from fatigue after dialysis will be recorded at the 0th and 4th weeks.

ETHICS/DISSEMINATION

This trial has undergone ethical scrutiny and been approved by the ethics review board of Chang Gung Memorial Hospital (Permission number: 102-4749A3 and 104-3156C). The pre-results of this trial will help to determine whether Tianjiu is an effective and safe treatment for IDH, and, if so, whether it is a therapeutic effect rather than a placebo effect.

TRIAL REGISTRATION NUMBER

NCT02210377; Pre-results.

Risk of Nonarteritic Anterior Ischemic Optic Neuropathy Following End-Stage Renal Disease

To investigate the risk of nonarteritic anterior ischemic optic neuropathy (NAION) following end-stage renal disease (ESRD).A retrospective, nationwide, matched cohort study.ESRD patients identified by the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code 585.The study cohort included 93,804 ESRD patients registered with the Taiwan National Health Insurance Research Database between January 2000 and December 2009. An age- and sex-matched control group comprised 93,804 patients (case:control = 1:1) selected from the Taiwan Longitudinal Health Insurance Database 2000. Information for each patient was collected from the index date until December 2011. The incidence and risk of NAION were compared between the ESRD and control groups. The adjusted hazard ratio (HR) for NAION after adjustment for potential confounders was obtained by a Cox proportional hazard regression analysis. A Kaplan-Meier analysis was used to calculate the cumulative incidence rate of NAION.The incidence of NAION following ESRD.In total, 133 ESRD patients (0.14%) and 51 controls (0.05%) had NAION (P < 0.001) during the follow-up period, leading to a significantly elevated risk of NAION in the ESRD patients compared with the controls (incidence rate ratio = 3.14, 95% confidence interval [CI] = 2.11-4.67). After adjustment for potential confounders including diabetes mellitus, hypertension, hypotension, hyperlipidemia, and 2-way interaction terms between any 2 factors, ESRD patients were 3.12 times more likely to develop NAION than non-ESRD patients in the full cohort (adjusted HR = 3.12, 95% CI = 2.10-4.64). Additionally, patients with hypertension and hyperlipidemia showed higher incidence rates of NAION in the ESRD group compared with the controls: 2.31 (95% CI = 1.40-3.82) for hypertension and 2.72 (95% CI = 1.14-6.50) for hyperlipidemia.ESRD increased the risk of NAION, which is an interdisciplinary emergency. Close collaboration between nephrologists and ophthalmologists is important in NAION management following ESRD to prevent fellow eye involvement.

Prevalence of intradialytic hypotension, clinical symptoms and nursing interventions--a three-months, prospective study of 3818 haemodialysis sessions

Background

Intradialytic hypotension (IDH) is considered one of the most frequent complications of haemodialysis with an estimated prevalence of 20–50 %, but studies investigating its exact prevalence are scarce. A complicating factor is that several definitions of IDH are used. The goal of this study was, to assess the prevalence of IDH, primarily in reference to the European Best Practice Guideline (EBPG) on haemodynamic instability: A decrease in systolic blood pressure (SBP) ≥20 mmHg or in mean arterial pressure (MAP) ≥10 mmHg associated with a clinical event and the need for nursing intervention.

Methods

During 3 months we prospectively collected haemodynamic data, clinical events, and nursing interventions of 3818 haemodialysis sessions from 124 prevalent patients who dialyzed with constant ultrafiltration rate and dialysate conductivity. Patients were considered as having frequent IDH if it occurred in >20 % of dialysis sessions.

Results

Decreases in SBP ≥20 mmHg or MAP ≥10 mmHg occurred in 77.7 %, clinical symptoms occurred in 21.4 %, and nursing interventions were performed in 8.5 % of dialysis sessions. Dialysis hypotension according to the full EBPG definition occurred in only 6.7 % of dialysis sessions. Eight percent of patients had frequent IDH.

Conclusions

The prevalence of IDH according to the EBPG definition is low. The dominant determinant of the EBPG definition was nursing intervention since this was the component with the lowest prevalence. IDH seems to be less common than indicated in the literature but a proper comparison with previous studies is complicated by the lack of a uniform definition.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0231-9) contains supplementary material, which is available to authorized users.

Increased Hepato-Splanchnic Vasoconstriction in Diabetics during Regular Hemodialysis

Background and Objectives

Ultrafiltration (UF) of excess fluid activates numerous compensatory mechanisms during hemodialysis (HD). The increase of both total peripheral and splanchnic vascular resistance is considered essential in maintaining hemodynamic stability. The aim of this study was to evaluate the extent of UF-induced changes in hepato-splanchnic blood flow and resistance in a group of maintenance HD patients during regular dialysis.

Design, Setting, Participants, & Measurements

Hepato-splanchnic flow resistance index (RI) and hepato-splanchnic perfusion index (QI) were measured in 12 chronic HD patients using a modified, non-invasive Indocyaningreen (ICG) dilution method. During a midweek dialysis session we determined RI, QI, ICG disappearance rate (k_ICG), plasma volume (V_p), hematocrit (Hct), mean arterial blood pressure (MAP) and heart rate (HR) at four times in hourly intervals (t₁ to t₄). Dialysis settings were standardized and all patient studies were done in duplicate.

Results

In the whole study group mean UF volume was 1.86 ± 0.46 L, V_p dropped from 3.65 ± 0.77L at t₁ to 3.40 ± 0.78L at t₄, and all patients remained hemodynamically stable. In all patients RI significantly increased from 12.40 ± 4.21 mmHg∙s∙m²/mL at t₁ to 14.94 ± 6.36 mmHg∙s∙m²/mL at t₄ while QI significantly decreased from 0.61 ± 0.22 at t₁ to 0.52 ± 0.20 L/min/m² at t₄, indicating active vasoconstriction. In diabetic subjects, however, RI was significantly larger than in non-diabetics at all time points. QI was lower in diabetic subjects.

Conclusions

In chronic HD-patients hepato-splanchnic blood flow substantially decreases during moderate UF as a result of an active splanchnic vasoconstriction. Our data indicate that diabetic HD-patients are particularly prone to splanchnic ischemia and might therefore have an increased risk for bacterial translocation, endotoxemia and systemic inflammation.

A randomized, placebo-controlled, phase 2 study of the efficacy and safety of droxidopa in patients with intradialytic hypotension

INTRODUCTION

Intradialytic hypotension (IDH) is the most common complication of hemodialysis (HD), and it plays a significant role in the morbidity and mortality associated with maintenance HD.

METHODS

This was a placebo-controlled, parallel-group study evaluating efficacy and safety of droxidopa in improving intradialytic blood pressure (BP) responses in 85 adults with end-stage renal disease (ESRD) and prone to IDH. Following screening and baseline periods, patients received 400 mg or 600 mg droxidopa, or placebo, orally 1 hour before HD for 4 weeks. Primary outcome endpoint was the change between baseline and last 2 treatment weeks in average mean arterial pressure (MAP) during HD. Also assessed were changes from baseline in systolic BP (SBP) and diastolic BP (DBP) during and after HD; number of hypotension-induced interventions and symptoms; and adverse events.

RESULTS

Increase in droxidopa intra-HD MAP were not significantly different from placebo, although droxidopa groups showed significant improvements in mean SBP after HD of +4.8 ± 11.6 mm Hg (600-mg) and +3.4 ± 13.1 (400-mg) compared with -4.4 ± 17.9 mm Hg in placebo, and the drop seen in mean nadir SBP pre- to intra-HD was also reduced. Changes in mean DBP pre- and post-HD, changes in mean nadir SBP post-HD, or intra-HD SBP were not significant over the treatment period. HD terminations decreased 5-fold in the 600-mg group and 2-fold in the 400-mg group, whereas the number of discontinuations stayed unchanged in the placebo group. Overall, treatment with 600-mg or 400-mg droxidopa was well tolerated in this population.

CONCLUSION

These data suggest that droxidopa may have a role in reducing IDH complications in patients with ESRD on chronic HD.

Promoting Kidney Function Recovery in Patients with AKI Requiring RRT

AKI requiring RRT is associated with high mortality, morbidity, and long-term consequences, including CKD and ESRD. Many patients never recover kidney function; in others, kidney function improves over a period of many weeks or months. Methodologic constraints of the available literature limit our understanding of the recovery process and hamper adequate intervention. Current management strategies have focused on acute care and short-term mortality, but new data indicate that long-term consequences of AKI requiring RRT are substantial. Promotion of kidney function recovery is a neglected focus of research and intervention. This lack of emphasis on recovery is illustrated by the relative paucity of research in this area and by the lack of demonstrated effective management strategies. In this article the epidemiologic implications of kidney recovery after AKI requiring RRT are discussed, the available literature and its methodologic constraints are reviewed, and strategies to improve the understanding of factors that affect kidney function recovery are proposed. Measures to promote kidney function recovery are a serious unmet need, with a great potential to improve short- and long-term patient outcomes.

Shenfu injection for intradialytic hypotension: a systematic review and meta-analysis

Objective. To evaluate the effectiveness and safety of Shenfu injection (SFI) for intradialytic hypotension (IDH). Methods. A systematic review of data sources published as of April 2014 was conducted. These included the Cochrane Central Register of Controlled Trials (2014 issue 4), Pubmed, Embase, CBM, CNKI, VIP, and Wangfang Data. Randomized controlled trials (RCTs) involving SFI for treatment and prevention of IDH were identified. Two researchers independently selected articles, extracted data, assessed quality, and cross checked the results. Revman 5.2 was used to analyze the results. Results. Eight RCTs were included. The meta-analysis indicated that compared with conventional therapies alone, SFI could elevate systolic blood pressure (SBP), increase the clinical effective rate, decrease the incidence of hypotension, increase serum albumin (ALB) levels, and reduce C-reactive protein (CRP) levels without serious adverse effects. GRADE Quality of Evidence. the quality of SBP, the effective rate, ALB, and CRP were low, and hypotension incidence and DBP were very low. Conclusions. SFI is more effective than conventional therapies for prevention and treatment of IDH. However, a clinical recommendation is not warranted due to the small number of studies included and low methodology quality. Multi-center and high-quality RCTs with large sample sizes are needed to provide stronger evidence.

The choice of dialysate sodium is influenced by hemodialysis frequency and duration: what should it be and for what modality?

Cardiovascular disease is the leading cause of mortality in hemodialysis patients. A chronic state of volume and pressure overload contributes, and central to this is the net sodium balance over the course of a hemodialysis. Of recent interest is the contribution of the dialysate sodium concentration (Dial-Na+) to clinical outcomes. Abundant evidence confirms that in thrice-weekly conventional hemodialysis, higher Dial-Na+ associates with increased intradialytic weight gain, blood pressure, and cardiovascular morbidity and mortality. On the other hand, low Dial-Na+ associates with intradialytic hypotension in the same patient population. However, the effect of Dial-Na+ in short hours daily hemodialysis (SHD; often referred to as "quotidian" dialysis), or nocturnal dialysis (FHND) is less well studied. Increased frequency and duration of exposure to a diffusive sodium gradient modulate the way in which DPNa+ alters interdialytic weight gain, predialysis blood pressure, and intradialytic change in blood pressure. Furthermore, increased dialysis frequency appears to decrease the predialysis plasma sodium setpoint (SP), which is considered stable in conventional thrice-weekly patients. This review discusses criteria to determine optimal Dial-Na+ in conventional, SHD and FHND patients, and identifies areas for future research.