Figure 1. The propofol and alfentanil infusion rates (A), propofol and alfentanil concentrations (B and C, respectively), time for recovery from anesthesia (D), and percentage decrease required for recovery (E) for an anesthetic regimen that provides 50% probability of response to intraabdominal surgery and the most rapid emergence from anesthesia, based on the interaction models of Vuyk et al. [1]The regimen assumes intubation at time 0, after a 0.7-mg/kg propofol bolus 2.3 min before intubation and a 30-micro gram/kg alfentanil bolus 1.4 min before intubation.