Background: To estimate the number of hospital admittance's avoidable by means of ambulatory surgery, according to surgeons and anaesthetists who currently work with the National Health System (NHS).
Method: By means of a Delphi procedure of 25 surgeons or anaesthetists of the Valencia Health Survey (AServei Valencià de la Salut-SVS), a consensus was reached as to the objective criteria for excluding patients that could be treated outside a hospital and the percentage of certain operations that could be performed under day surgery. These criteria were applied to the Minimum Basic Data Set on hospital discharge within the Autonomous Region of Valencia in order to estimate the figure of hospital admittance and stays avoidable by means of ambulatory surgery in a selection of 29 surgery processes.
Results: 83% of medical personnel responded to the Delphi questionnaires. The median of the surveyed group's estimation on the proportion of cases that could be treated by means of external surgery varied from 40% for abdomen wall hernias or laparoscopic cholecystectomy and 90% for perianal tissue excision, anastomosis for dialysis or ganglionectomy. Application of the results of the Delphi survey would have meant that the SVS could have avoided 12,558 admittances in 1994, 75% of the operations surveyed, which is almost the same figure resulting from applying the medical personnel's opinion of the CMBD.
Conclusions: SVS professionals consider it feasible to perform a much higher number of ambulatory operations than those currently carried out, and that it is likely that the causes for the lack of such operations lie in SNS financing and incentive criteria, rather than medical issues.