Fig. 3. (  Top ) Bar plot distribution of the difference ± SD between Vasotrac and directly measured blood pressure (BP) readings for systolic, diastolic, and mean BP measurements. Each difference between the Vasotrac and intraarterial BP measurements was categorized into a specific range spanning 5 mmHg. For each patient, the distribution was then computed as a percentage of the total number of measurements. All of these distributions were combined to produce an average distribution of Vasotrac − intraarterial BP (shown as mean ± SD). (  Bottom ) Bland–Altman Plots for systolic, diastolic, and mean BP showing level of agreement over the entire range of BP measurements between 17,468 simultaneous readings obtained by the Vasotrac and intraarterially. The horizontal lines represent the mean difference along with one SD and two SDs of this difference. There is a paucity of data points < 45 mmHg mean BP.