Predictability failure in glucose-insulin system for ICU patients
Modern medicine implicitly assumes that physiological responses to intervention are predictably determined by administered treatments. However, physiological systems containing intrinsic delays between the detection of a stimulus and the biological response may violate this assumption. We investigate the human glucose-insulin system as described by the Ultradian model and mathematically…
The human glucose-insulin system, as described by the Ultradian model, may exhibit unpredictable responses to treatments due to intrinsic delays. Modern medicine often assumes a predictable relationship between administered interventions and physiological responses, but this assumption may be flawed. In the ICU setting, pulsatile insulin delivery and step-wise glucose infusion are common protocols.
However, these common methods can lead to temporal chaos if they are not properly accounted for. This phenomenon, called delay-induced uncertainty (DIU), occurs through the interaction of physiological delays, intrinsic shear near a limit cycle, and external forcing. By using the Ultradian glucose-insulin model, researchers calculated top Lyapunov exponents to measure predictability.
They found positive Lyapunov exponents in various pulsatile and step-wise forcing regimes, indicating sustained chaos. These findings suggest that delayed endocrine regulation may fundamentally limit the predictive value of models used in glycemic management strategies. This has implications for clinical protocols in the ICU, as it could create difficulties in achieving optimal dosing and timing when administering glucose and insulin to patients.
Written by urgent.news from bioRxiv's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
