Figure 3. Plots of the potency of negative inotropic effects of anesthetics on human atrial tissue with data from animal experiments. IC sub 50 values from this study on the x-axis are plotted against comparable data from animal studies on the y-axis. Most data are from in vitro studies of isolated heart preparations and some from other forms of isolated heart experiments. Data are from various studies using different experimental conditions. The nature of the data is provided in symbols. Circle = contractility studies of isolated ventricular tissue; square = contractility studies of isolated atrial muscle; diamond = other studies of contractility in models of isolated heart preparations. Species are depicted in the symbols and abbreviated as follows: R = rabbit; G = guinea pig; F = ferret; D = dog. Data are from the following studies: propofol, references 5, 6, 8, and 11; thiopental, [5,9-11,12,28]; midazolam, [32]; etomidate, [13,14,35]; and ketamine, [15-17].