Efficacy and safety of propofol target-controlled infusion combined with butorphanol for sedated colonoscopy

Figure 1 Target propofol concentrations in plasma for consecutive patients of each group and the response to the procedures. A: Target propofol concentrations in plasma for consecutive patients in the control group (group C); B: Target propofol concentrations in plasma for consecutive patients in group B1; C: Target propofol concentrations in plasma for consecutive patients in group B2. The target propofol concentrations in plasma for consecutive patients in each group and the response to the procedures were used to calculate the median effective concentration (EC50), which is the concentration required to achieve the half maximal effectiveness of propofol. The resulting EC50 for each group and 95% confidence intervals are presented in Table 2.