Using more frequent haemodialysis to manage volume overload in dialysis patients with heart failure, obesity or pregnancy

The relative potential contribution of volume load and vascular mechanisms to hypertension in non-dialysis and dialysis chronic kidney disease patients

Background

Hypertension is highly prevalent and particularly difficult to treat adequately in patients with chronic kidney disease (CKD). The relative contribution of volume overload and vascular mechanisms to blood pressure measures in CKD and whether these effects differ in non-dialysis compared to dialysis patients is unknown.

Methods

We determined the potential impact of volume load (stroke volume) and vascular mechanisms (inverse of total arterial compliance (inv TAC) and systemic vascular resistance (SVR)) on mean and brachial and aortic systolic blood pressures in 67 non-dialysis and 48 dialysis chronic kidney disease (CKD) patients. Relationships were determined in confounder adjusted regression models.

Results

Stroke volume (p value = 0.003) was more strongly associated with mean arterial pressure than SVR (p value = 0.9) (p value for difference = 0.03). When stroke volume and SVR were entered in the same regression model (model R2 = 0.324), they contributed equally to the variation in mean arterial pressure (p value for difference = 0.5). Stroke volume (p value ≤ 0.002) and inv TAC (p value ≤ 0.001) contributed equally to the variation in systolic pressures (p value for difference ≥ 0.9). When stroke volume and inv TAC were entered in the same regression model (model R2 = 0.752 to 0.765), they contributed equally to the variation in systolic blood pressures (p value for difference = 0.7). Stroke volume, TAC and SVR were similar (p value ≥ 0.5) and associated to the same extent with blood pressure measures in non-dialysis and dialysis CKD patients (p value for difference ≥ 0.1). In receiver operator characteristic curve analysis, elevated systolic blood pressure was determined by stroke volume (p value = 0.005) and inv TAC (p value = 0.03) but not SVR (p value = 0.8). The calculated power of the study was 0.999 based on α = 0.05.

Conclusions

The present investigation suggests that both volume load and vascular mechanisms should be considered in the management of hypertension among patients with CKD. The extent and relative potential impact of volume load and vascular mechanisms on blood pressure measures are as large in non-dialysis compared to dialysis CKD patients.

Cardiorenal syndrome in the pediatric population: A systematic review

The concept of cardiorenal syndrome (CRS) is derived from the crosstalk between the heart and kidneys in pathological conditions. Despite the rising importance of CRS, there is a paucity of information on the understanding of its pathophysiology and management, increasing both morbidity and mortality for patients. This review summarizes the existing conceptual pathophysiology of different types of CRS and delves into the associated therapeutic modalities with a focus on pediatric cases. Prospective or retrospective observational studies, comparative studies, case reports, case-control, and cross-sectional studies that include pediatric patients with CRS were included in this review. Literature was searched using PubMed, EMBASE, and Google Scholar with keywords including "cardio-renal syndrome, type," "reno-cardio syndrome," "children," "acute kidney injury," and "acute decompensated heart failure" from January 2000 to January 2021. A total of 14 pediatric studies were ultimately included and analyzed, comprising a combined population of 3608 children of which 32% had CRS. Of the 14 studies, 57% were based on type 1 CRS, 14% on types 2 and 3 CRS, and 7% were on types 4 and 5 CRS. The majority of included studies were prospective cohort, although a wide spectrum was observed in terms of patient age, comorbidities, etiologies, and treatment strategies. Commonly observed comorbidities in CRS type 1 were hematologic, oncologic, cardiology-related side effects, muscular dystrophy, and pneumonia/bronchiolitis. CRS, particularly type 1, is prevalent in children and has a significant risk of mortality. The current treatment regimen primarily involves diuretics, extracorporeal fluid removal, and treatment of underlying etiologies and comorbidities.

Sodium First Approach, to Reset Our Mind for Improving Management of Sodium, Water, Volume and Pressure in Hemodialysis Patients, and to Reduce Cardiovascular Burden and Improve Outcomes

New physiologic findings related to sodium homeostasis and pathophysiologic associations require a new vision for sodium, fluid and blood pressure management in dialysis-dependent chronic kidney disease patients. The traditional dry weight probing approach that has prevailed for many years must be reviewed in light of these findings and enriched by availability of new tools for monitoring and handling sodium and water imbalances. A comprehensive and integrated approach is needed to improve further cardiac health in hemodialysis (HD) patients. Adequate management of sodium, water, volume and hemodynamic control of HD patients relies on a stepwise approach: the first entails assessment and monitoring of fluid status and relies on clinical judgement supported by specific tools that are online embedded in the HD machine or devices used offline; the second consists of acting on correcting fluid imbalance mainly through dialysis prescription (treatment time, active tools embedded on HD machine) but also on guidance related to diet and thirst management; the third consist of fine tuning treatment prescription to patient responses and tolerance with the support of innovative tools such as artificial intelligence and remote pervasive health trackers. It is time to come back to sodium and water imbalance as the root cause of the problem and not to act primarily on their consequences (fluid overload, hypertension) or organ damage (heart; atherosclerosis, brain). We know the problem and have the tools to assess and manage in a more precise way sodium and fluid in HD patients. We strongly call for a sodium first approach to reduce disease burden and improve cardiac health in dialysis-dependent chronic kidney disease patients.

Managing heart failure in dialysis patients

The heart and the kidney are intimately connected. They communicate in a bidirectional manner through a variety of pathways, forming an interdependent relationship. Recognition of this co-dependency is crucial in managing patients with cardiorenal syndrome, as we begin to realise the inevitability of disease progression to both organs; and an approach that focuses treatment on one organ may result in worsening outcome on the other organ. When faced with patients with deteriorating cardiac disease, nephrologists tend to focus on stabilisation of cardiac function and accept the heart disease to be unmodifiable. Likewise, cardiac patients with persistent kidney failure are presented with a poor renal prognosis and prepared for kidney transplantation. Adopting a cardio-protective approach in combination with dialysis optimisation raises hope for a more positive outcome with evidence of cardiac and renal recovery in some patients.