Can Bioimpedance Analysis Be Used to Estimate Absolute Blood Volume in Hemodialysis Patients?

Introduction: Under physiological conditions, blood volume and extracellular volume are in a ratio of 1-3, even in hemodialysis patients. The question therefore arises: can blood volume be inferred from the bioimpedance analysis data? The aim of the study was to compare the blood volumes calculated from extracellular volume determined by bioimpedance analysis data to the actually measured blood volumes.

Methods: Immediately before treatment, extracellular volume and volume overload were evaluated by bioimpedance spectroscopy.

Absolute blood volume and long-term survival in chronic hemodialysis patients.

Current online hemodiafiltration devices can be used to determine the absolute blood volume in clinical practice using the dialysate bolus method. Most of publications on this method have focused on preventing intradialytic complications. The influence of absolute blood volume on long-term prognosis has not been reported yet.

Vascular refilling in hemodialysis using feedback-controlled ultrafiltration profile.

Background: The rate and the duration of ultrafiltration (UF) are considered the most important factors to affect vascular refilling. The aim of the study was to investigate whether a UF profile could improve the vascular refilling.

Methods: Dialysis was delivered by a machine providing feedback control of ultrafiltration rates.

Vascular refilling depends on the ratio of blood volume to extracellular volume in hemodialysis patients.

The ratio of blood volume to extracellular volume is approximately one to three under physiological conditions and also in stable chronic hemodialysis patients. Recently, it was found that this ratio remains unchanged during hemodialysis despite ultrafiltration. This would signify that the higher the ratio, the lower the refilling and vice versa.

Marine macroinvertebrate ecosystem services under changing conditions of seagrasses and mangroves.

This study aimed to investigate the impact of changing environmental conditions on MMI ES in seagrasses and mangroves. We used data from satellite and biodiversity platforms combined with field data to explore the links between ecosystem pressures (habitat conversion, overexploitation, climate change), conditions (environmental quality, ecosystem attributes), and MMI ES (provisioning, regulation, cultural). Both seagrass and mangrove extents increased significantly since 2016.

Developing conceptual models that link multiple ecosystem services to ecological research to aid management and policy, the UK marine example.

Our understanding of ecological processes that lead to ecosystem services is still evolving but ecological research aims to understand the linkages between the ecosystem and services. These linkages can affect trade-offs between different ecosystem services. Understanding these linkages, by considering multiple ecosystem services simultaneously supports management of the environment and sustainable use of resources.

Valuing biodiversity and ecosystem services: a useful way to manage and conserve marine resources?

Valuation of biodiversity and ecosystem services (ES) is widely recognized as a useful, though often controversial, approach to conservation and management. However, its use in the marine environment, hence evidence of its efficacy, lags behind that in terrestrial ecosystems. This largely reflects key challenges to marine conservation and management such as the practical difficulties in studying the ocean, complex governance issues and the historically-rooted separation of biodiversity conservation and resource management.

Bioremediation of waste under ocean acidification: Reviewing the role of Mytilus edulis.

Waste bioremediation is a key regulating ecosystem service, removing wastes from ecosystems through storage, burial and recycling. The bivalve Mytilus edulis is an important contributor to this service, and is used in managing eutrophic waters. Studies show that they are affected by changes in pH due to ocean acidification, reducing their growth.