Fig. 2.
Probability of analgesia and respiratory depression. (A) Probability of analgesia versus effect-site concentration for P(A(CE) > 0.25) (orange lines) and P(A(CE) > 0.5) (blue lines). (B) Probability of respiratory depression versus effect-site concentration for P(R(CE) > 0.5). (C) Probability of analgesia versus time after a bolus infusion of 50 µg alfentanil for P(A(t) > 0.25) (orange lines) and P(A(t) > 0.5) (blue lines). (D) Probability of respiratory depression versus time after a bolus infusion of 50 μg alfentanil for P(R(t) > 0.5). The broken lines are the 95% CIs.