Association of intradialytic hypotension and convective volume in hemodiafiltration: results from a retrospective cohort study

Prevention of Intradialytic Hypotension in Hemodialysis Patients: Current Challenges and Future Prospects

Intradialytic hypotension, defined as rapid decrease in systolic blood pressure of greater than or equal to 20 mmHg or in mean arterial pressure of greater than or equal to 10 mmHg that results in end-organ ischemia and requires countermeasures such as ultrafiltration reduction or saline infusion to increase blood pressure to improve patient's symptoms, is a known complication of hemodialysis and is associated with several potential adverse outcomes. Its pathogenesis is complex and involves both patient-related factors such as age and comorbidities, as well as factors related to the dialysis prescription itself. Key factors include the need for volume removal during hemodialysis and a suboptimal vascular response which compromises the ability to compensate for acute intravascular volume loss. Inadequate vascular refill, incorrect assessment or unaccounted changes of target weight, acute illnesses and medication interference are further potential contributors. Intradialytic hypotension can lead to compromised tissue perfusion and end-organ damage, both acutely and over time, resulting in repetitive injuries. To address these problems, a careful assessment of subjective symptoms, minimizing interdialytic weight gains, individualizing dialysis prescription and adjusting the dialysis procedure based on patients' risk factors can mitigate negative outcomes.

The clinical efficacy of Shenmai injection in the prophylaxis and treatment of intradialytic hypotension: A protocol for systematic review and meta-analysis

BACKGROUND

Intradialytic hypotension (IDH) is a common complication in hemodialysis. IDH can induce vomiting, chest tightness and syncope, and hemodialysis shall be discontinued in patients with severe IDH. As is revealed in related studies, Shenmai injection (SMI) can be used in the prophylaxis and treatment of IDH. However, there is still a lack of consensus about the efficacy among reported studies, which cannot provide compelling evidence. Therefore, a meta-analysis was conducted in this study to further investigate the efficacy and safety of SMI in the prophylaxis and treatment of IDH.

METHODS

PubMed, Web of Science, Scopus, Cochrane Library, Embase, China Scientific Journal Database, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and Wanfang Data were systematically retrieved from their establishment to June 2022. Subsequently, literature screening, data extraction, quality evaluation and cross-checking of results were performed according to the Cochrane Handbook. Besides, a meta-analysis was performed with the assistance of Revman 5.3 software.

RESULTS

This study will evaluate whether SMI is effective in the prophylaxis and treatment of IDH.

CONCLUSIONS

The latest evidence for the efficacy and safety of SMI in the prevention and treatment of IDH can be provided through this study.

Comparison of the Impact of Conventional Hemodialysis and Hemodiafiltration Techniques on the Evolution of Certain Mineral Bone Parameters in Chronic Hemodialysis Patients

Objective: The aim of this study was to compare the impact of conventional hemodialysis (HDC) and hemodiafiltration (HDF) techniques on the evolution of the parameters of phosphocalcic metabolism in chronic hemodialysis patients. Methods: This is a retrospective, descriptive and analytical study carried out in the hemodialysis center of Agadir medico-surgical center during 2015. The total number of patients is 34, 18 were treated by HDC ie 52.9% of cases. Also, 16 patients underwent HDF, ie 47.1% of cases. With each of the 2 techniques, the following parameters were measured: To assess the PTH level, we performed 3 measurements. To evaluate calcium, phosphorus, albumine and CRP levels, 7 measurements were taken. The data were entered via Excel and analyzed through Jamovi 1.6.9 software. We used the Wilcoxon or the Mann-Whitney test for the means. The factors associated with the variation of the studied parameters were analyzed in univariate and multivariate analyzes using the binary logistic regression model. Results: Our population was made up of 41.2% women and 58.8% men. Their average age was 55 ± 11 years. Also, 82.3% of cases had a normal build, 11.7% were overweight and 6% were moderately obese. The distribution of patients according to the causal nephropathy of chronic renal insufficiency presented a predominance of diabetic nephropathy (32.3%) followed by vascular pathology in 10 patients (29.4%). There was no statistically significant difference in the evolution of the levels of the parameters studied (PTH, calcium, phosphorus, albumin and CRP levels) over time. Univariate analysis showed that only the initial nephropathy factors: other nephropathy-vascular nephropathy (p= 0.028; OR=0.060; IC95% [0.004-0.734]) and diabetic nephropathy-vascular nephropathy (p= 0.011; OR=0.050; IC95% [0.004-0.508]) were associated with the variation of the studied parameters. The same factors also emerge in the multivariate analysis: other nephropathy-vascular nephropathy (p= 0.034; OR=0.044; IC95% [0.002-0.791]) and diabetic nephropathy-vascular nephropathy (p= 0.009; OR=0.032; IC95% [0.002-0.429]).   Conclusion: According to our results, it seems that there are no significant differences in the evolution of some mineral bone parameters studied with the HDC and HDF techniques.

Quality of Life and Hemodynamic Effects of Switching From Hemodialysis to Hemodiafiltration: A Canadian Controlled Cohort Study

Background:

Recent randomized clinical trials have demonstrated beneficial effects of hemodiafiltration (HDF) compared with hemodialysis (HD) on mortality and hemodynamic stability. Data on quality of life in HDF compared with HD is limited.

Objective:

This study aimed to determine whether patients receiving HD experience improvements in quality of life, hemodynamic and laboratory parameters after switching to HDF.

Design:

Observational controlled cohort study.

Setting & Patients:

Adult patients receiving maintenance dialysis were followed for 3 months both before and after transfer to a new unit, where they received HDF. Prior to transfer, control patients were already treated by HDF.

Methods:

Quality of life at baseline and follow-up was measured using the validated minutes to recovery (MR) question. Dialysis data were collected for 3 consecutive sessions monthly; laboratory values were collected monthly. Wilcoxon signed rank test and repeated measures analysis of covariance were used to evaluate pre/post transfer changes and quantile regression to identify predictors of change in recovery time.

Results:

Of 227 patients, 82 died, were transplanted, were hospitalized or did not transfer, leaving 123 subjects and 22 controls for analysis. MR did not improve with switching to HDF, although patients with MR > 60 min before transfer experienced a significant decrease in their MR, compared with controls. There was no improvement in intradialytic hypotension with HDF. There were no differences in laboratory values before vs after switch.

Limitations:

Nonrandomized single-center study, including only small numbers of patients and covering a short follow-up period; hemodynamic values only evaluated over 1 week per month; residual kidney function not recorded.

Conclusions:

In this Canadian experience of HDF, patients remained stable with respect to several laboratory and dialysis related parameters. Switch to HDF was associated with substantially reduced recovery time in patients with MR > 60 minutes at baseline.

Online hemodiafilteration use in children: a single center experience with a twist

Background

Haemodiafilteration (HDF) is a promising new modality of renal replacement therapy (RRT). It is an improvement in the quality of hemodialysis (HD) and thus in the quality of patients’lives. The main obstacle to using HDF is the cost, especially in developing countries. The purpose of this study was to evaluate the benefits of incorporating HDF with different regimens in the treatment of children with end stage renal disease (ESRD).

Methods

Thirty-four children with ESRD on regular HD in Pediatric Dialysis Unit, Children’s Hospital, Ain Shams University were followed up in 2 phases: initial phase (all patients: HD thrice weekly for 3 months) and second phase, patients were randomized into 2 groups, HDF group and HD group, the former was subdivided into once and twice weekly HDF subgroups. Evaluation using history, clinical and laboratory parameters at 0, 3, 9 and 18 months was carried out.

Results

On short term, we found that the HDF group was significantly superior to HD group regarding all clinical and laboratory parameters. Also, twice HDF subgroup was significantly superior to once HDF subgroup. This was confirmed on long term follow up, but the once HDF proved comparable to twice subgroup.

Conclusions

Incorporating online hemodiafilteration (OL-HDF) in the RRT of children was beneficial in most of the clinical and laboratory parameters measured. It’s not all or non; OL-HDF, even once a week, can improve outcomes of HD without significantly affecting the cost.

Blood pressure and volume management in dialysis: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Blood pressure (BP) and volume control are critical components of dialysis care and have substantial impacts on patient symptoms, quality of life, and cardiovascular complications. Yet, developing consensus best practices for BP and volume control have been challenging, given the absence of objective measures of extracellular volume status and the lack of high-quality evidence for many therapeutic interventions. In February of 2019, Kidney Disease: Improving Global Outcomes (KDIGO) held a Controversies Conference titled Blood Pressure and Volume Management in Dialysis to assess the current state of knowledge related to BP and volume management and identify opportunities to improve clinical and patient-reported outcomes among individuals receiving maintenance dialysis. Four major topics were addressed: BP measurement, BP targets, and pharmacologic management of suboptimal BP; dialysis prescriptions as they relate to BP and volume; extracellular volume assessment and management with a focus on technology-based solutions; and volume-related patient symptoms and experiences. The overarching theme resulting from presentations and discussions was that managing BP and volume in dialysis involves weighing multiple clinical factors and risk considerations as well as patient lifestyle and preferences, all within a narrow therapeutic window for avoiding acute or chronic volume-related complications. Striking this challenging balance requires individualizing the dialysis prescription by incorporating comorbid health conditions, treatment hemodynamic patterns, clinical judgment, and patient preferences into decision-making, all within local resource constraints.

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 impact of dialysis modality and membrane characteristics on intradialytic hypotension

The risk of intradialytic hypotension (IDH) is determined by various factors, among them dialysis modality and dialyzer membrane. We conducted a literature search in PubMed on November 1, 2016 and selected relevant randomized controlled and cross-over trials, and prospective and retrospective cohort studies published in English that investigated the association between IDH and dialysis modality and membrane, respectively. This literature search revealed 669 publications on dialysis modality, 64 on dialysis membrane, and 24 on acetate/bicarbonate dialysate. After omission of duplicate papers and publications outside the scope of this review, we selected 34 papers for inclusion, 19 on dialysis modality, 8 on dialyzer membrane, and 7 on acetate/bicarbonate dialysate. Several strands of evidence indicate that hemodiafiltration (HDF) is associated with lower IDH rates compared to hemodialysis (HD). Data do not show an unequivocal benefit of synthetic vs nonsynthetic dialyzer membranes with respect to IDH occurrence. Acetate-based vs bicarbonate-based dialysate appears to be associated with an increased IDH rate.

Treatment tolerance and patient-reported outcomes favor online hemodiafiltration compared to high-flux hemodialysis in the elderly

Large cohort studies suggest that high convective volumes associated with online hemodiafiltration may reduce the risk of mortality/morbidity compared to optimal high-flux hemodialysis. By contrast, intradialytic tolerance is not well studied. The aim of the FRENCHIE (French Convective versus Hemodialysis in Elderly) study was to compare high-flux hemodialysis and online hemodiafiltration in terms of intradialytic tolerance. In this prospective, open-label randomized controlled trial, 381 elderly chronic hemodialysis patients (over age 65) were randomly assigned in a one-to-one ratio to either high-flux hemodialysis or online hemodiafiltration. The primary outcome was intradialytic tolerance (day 30-day 120). Secondary outcomes included health-related quality of life, cardiovascular risk biomarkers, morbidity, and mortality. During the observational period for intradialytic tolerance, 85% and 84% of patients in high-flux hemodialysis and online hemodiafiltration arms, respectively, experienced at least one adverse event without significant difference between groups. As exploratory analysis, intradialytic tolerance was also studied, considering the sessions as a statistical unit according to treatment actually received. Over a total of 11,981 sessions, 2,935 were complicated by the occurrence of at least one adverse event, with a significantly lower occurrence in online hemodiafiltration with fewer episodes of intradialytic symptomatic hypotension and muscle cramps. By contrast, health-related quality of life, morbidity, and mortality were not different in both groups. An improvement in the control of metabolic bone disease biomarkers and β2-microglobulin level without change in serum albumin concentration was observed with online hemodiafiltration. Thus, overall outcomes favor online hemodiafiltration over high-flux hemodialysis in the elderly.

Online-haemodiafiltration vs. conventional haemodialysis: a cross-over study

BACKGROUND

The main short-term advantages of haemodiafiltration (HDF) are supposedly better removal of Beta2-microglobulin (ß2-m) and phosphate, and better haemodynamic stability. The main disadvantage is higher costs. The aim of the study was to compare the clinical and biological parameters associated with HDF and high-flux haemodialysis (HD), using a cross-over design, while maintaining the same dialysis parameters.

METHODS

All patients on a 3 × 4 hours schedule were observed during 3 identical 6-months periods: HDF1 - HD - HDF2. The mean values for the 2 last months of each period were compared.

RESULTS

A total of 51 patients (76 % males, 45 % diabetic) with a mean age of 74 ± 15 years, and who had been on dialysis for 49 ± 60 months were included. The mean blood flow (329 ± 27 ml/min), dialysate flow (500 ml/min), and convection volumes (21.6 ± 3.2 L) were recorded. Patient medications were not changed. Predialysis blood pressure, phosphataemia, calcaemia, iPTH, Kt/V, nPNA and intradialytic events were similar throughout the 3 periods. Only serum albumin (34. 4 ± 3.6, 35.9 ± 3.4, 34.1 ± 4 g/L, p < 0. 0001) and ß2-m serum levels (26.1 ± 5.4, 28 ± 6, 26.5 ± 5 mg/L, p < 0.001, values shown for HDF1, HD, HDF2, respectively) were significantly lower during the HDF periods. Factor associated with higher delta serum albumin levels between HD and HDF periods was mainly a lower convection volume.

CONCLUSION

Comparing HDF and HD, we did not observe any differences in haemodynamic stability or in serum phosphate levels. Only serum ß2-m (-6% vs. HD) and albumin (-5% vs. HD) levels changed. The long-term clinical consequences of these biochemical differences should be prospectively assessed.