Use of interstitial fluid in tight glycaemic control in ICU is not without risk.
Dr Mark O’Connell comments on a recent paper. Read full article
The inherent weakness in all systems that rely on measuring interstitial fluid glucose (e.g. under the skin devices) is that they need clever algorithms to try to predict blood glucose. However, the relationship between these two compartments, interstitial fluid and blood, is very complex and not simply a time-lag. This has been highlighted in a recent paper by Cobelli et al., (attached), an internationally respected authority on controlling physiological systems, which has major implications for the development of a closed-loop artificial pancreas. Control theory states that to produce a desired output from a dynamical system it needs to be monitored accurately. The imperfect monitoring of blood glucose using interstitial fluid represents a significant risk to the patient.