Drug delivery system for general anesthesia: Where are we?

This paper provides an up-to-date review from the intersecting point of both clinical and engineering frameworks. The text interwoves available measures, models and control algorithms for general anesthesia. The three main parts of general anesthesia: neuromuscular blockade (NMB), hypnosis and analgesia are critically observed and perused from a global objective perspective. The outcome of this review is that quantifying and controlling depth of anesthesia is a challenging process and that current bottlenecks are singularly due to lack of direct measurement of analgesia during general anesthesia. Some ongoing efforts are recognized towards the development of a pain transmission model, possibly leading to the breakthrough required for analgesia sensor availability.