Publication details
Feedback-Feedforward model of cold face test response
| Authors | |
|---|---|
| Year of publication | 2009 |
| Type | Article in Proceedings |
| Conference | IFMBE Proc. World Congress on Medical Physics and Biomedical Engineering |
| MU Faculty or unit | |
| Citation | |
| Field | Medical equipment |
| Keywords | Cardiovascular Control Cold Face Test Feedback-Feedforward Control Sympathetic and Parasympathetic Response Thermoregulation |
| Description | This study deals with the development of a new model of the Cold Face Test (CFT). In humans, activation of the diving reflex by a cold stimulus to the face results in bradycardia and peripheral vasoconstriction. This study was undertaken to quantify the effect of cold face stimulation on the cardiovascular system. Our purpose was to develop mathematical models and fit measurement data obtained via heart rate, body temperature, and skin vascular resistance monitoring in order to quantify the level of parasympathetic and sympathetic discharge of the subjects. Responses of 14 healthy human subjects to CFT were analyzed and evaluated during application of a cold stimulus (around 0 degC) to the forehead for approx. 60 s. A feedback model of simplified thermoregulation in humans was developed. The model was augmented with a feed forward control component driven by the diving reflex. We used an adapted nonlinear least square algorithm and successfully demonstrated that our model can predict data obtained during CFT. The model reveals parameter estimates to quantify the level of sympathetic nerve activity on the vasculature and the level of parasympathetic nerve activity on the sinoatrial (SA) node in the heart. Additionally our model demonstrates that sympathetic nerve discharge on the sinoatrial node is negligible on the overall response to CFT. Finally the model shows that body core temperature is conserved during CFT. |