Figure 83-3 Chain of accident evolution in anesthesia. As in Reason's model (see Fig. 83-13 ), underlying latent failures (and the organizational culture) predispose to the triggering of an accident sequence by equipment, the patient, the surgeon, the anesthesiologist, and other personnel. This sequence can be prevented by prophylactic measures such as preoperative evaluation and treatment of patient diseases or pre-use checkout of life support equipment. Once a problem occurs, it may remain self-limited or it may evolve further down the accident chain. Using dynamic decision-making, the anesthetist must detect and correct the problems that do occur at the earliest possible point in the chain of evolution. The interruption of the accident chain is made more difficult when there is tight coupling within the system, when there are multiple interacting problems, or when problems disrupt recovery processes. Efficient use of incident analysis may make it easier in the future to prevent or interrupt problem evolution. (Redrawn with modification from Gaba DM, Fish KJ, Howard SK: Crisis Management in Anesthesiology. New York, Churchill Livingstone, 1994.)