Control parameters of the blood-pressure regulatory system - Part 2-Open-loop gain, reference pressure and basal heartrate

The open-loop gain G₀ reference pressure P₀ and basal heartrate R₀ of the blood-pressure regulatory system have been estimated under four different experimental conditions by employing an aortic balloon and assuming a theoretical approach based on a 1st-order linear model. Mean values of 1·7-3·7, 75-130 mmHg, and 95-130 beats/min were obtained for G₀, P₀ and R₀, respectively. Significant variations in these parameters were observed when the anaesthetic conditions were changed. It is suggested that G₀, P₀ and R₀ may have useful clinical applications both in characterising hypotensive and hypertensive syndromes and also in assessing the effect of anaesthetic agents.