The effect of osmolarity on optical blood volume sensors for hemodialysis applications

Optical sensors are commonly used in hemodialysis (HD) for the continuous estimation of relative blood volume (RBV) during the session. Recently, the reliability of these devices was put into question due to the possible influence of osmolarity on this type of measurements. In this work, we investigated this issue with an experimental setup which expands on traditional optical sensor designs for HD. With the new setup, we were able to confirm the presence of the osmolarity artifact, and to collect data in an extended domain, compared to traditional sensors. However, the extended measurements only gave hints about possible solutions for the osmolarity issue.