[Assessment by logistic model of hemodynamic changes during general anesthesia]

The anesthesia induction with strong anesthetic agents generally reduces blood pressure. Cardiovascular agents used during anesthesia induce hemodynamic changes. The time courses of systolic (sBP) and diastolic blood pressure (dBP) and heart rate (HR) are expressed as sigmoidal curve. We have found that the hemodynamic changes can be precisely curve-fitted with a logistic function giving non-linear curve. The four parameters of the logistic function present the first asymptote, the last asymptote, the slope at the inflection point, and the time to the inflection point. Moreover, each logistic parameter is used for the effects of drug dose, age and sex differences of subjects on the hemodynamic change. In this review, we introduce the analyses with the logistic function for the changes in sBP, and dBP during preintubation period and HR, sBP, and dBP during infusion of landiolol hydrochloride, an ultra-short-acting beta1-adrenergic receptor blocking agent, which is used for subjects with tachycardia during general anesthesia. The logistic parameters are useful for assessing the hemodynamic response during general anesthesia. The assessment method of the hemodynamic change using the logistic model contributes much to the management of anesthesia.