[Monitoring cancellations of surgical procedures: an indicator of organizational performance].

This descriptive and exploratory study aims at investigating the occurrence and causes for the cancellations of scheduled surgeries in the Surgical Center unit of a large school hospital in the interior of the State of São Paulo. Data were collected during three consecutive months in 2004 using institutional documents and forms elaborated by the researchers. In the period of study, 4,870 surgeries were scheduled in the investigated unit, of which 249 were suspended, an average of 5.1%. The main causes for the cancellations concerned the patients (57.8%), such as his/her absence (56.3%) and his/her unfavorable clinical conditions (34.7%); the unit's organization (22.1%), due to the lack of available beds for hospitalization (29.1%) and the occurrence of emergency surgeries (25.5%); and the allocation of human resources (17.7%) or of material resources and equipment (1.6%).