Figure 83-2 Schematic diagram of the dynamic adaptation of preoperative plans. The anesthetist begins the anesthetic with an intravenous (IV) induction as planned (top left). On achieving the milestone of successful induction of anesthesia, the blood pressure (BP) is checked before proceeding with laryngoscopy and intubation (center). If the BP is not satisfactory, the next step may be delayed and the plan amended to optimize the BP. If necessary, the case may even be aborted at this stage. Throughout the case, the anesthetist is vigilant for the occurrence of new problems ("police cars"). If a problem is detected, a process of reactive problem-solving takes place, which may result in new adaptations to the plan (in this case, treatment of bronchospasm). (From Gaba DM: Human error in dynamic medical environments. Hillsdale, NJ, Lawrence Erlbaum, 1994, pp 197–224.)