[Quality assurance in heart surgery: 8 years experience with a "feedback-control" system in Heidelberg]

An important aspect of quality assurance in cardiac surgery covers the epidemiological analysis of patient data. After an 8 year period of clinical experience with quality assurance, we summarize and evaluate current concepts and actual experiences regarding a special type of database application and organisation ("feedback-control-system") for quality assurance. It had been developed to meet and solve the problems related to the data acquisition process, that are typically present in the clinical routine of quality assurance. In 1988 the "feedback-control-system" was designed and implemented in the Department of Cardiac Surgery at Heidelberg University. Since then it had been continuously improved and adapted to satisfy current needs in cardiac surgery. More than 1500 items are now recorded routinely per patient. At present, detailed information of more than 10,000 patients is available for the specific methods of analysis in the field of quality assurance. The basic concept included 1. the integration of the data acquisition in the daily clinical routine, 2. the evaluation and improvement of collected data material by means of "output-functions", that require previously recorded reliable data (that is automatically computer generated operation reports, letters, statistics, accounting etc.), and 3. to ensure that the medical and non-medical staff members participate in the advantages and the responsibilities of the data-base system for quality assurance. Analyses of perioperative risks and results, early discovery of trends, identification of special subpopulations receiving special types of treatment in cardiac surgery etc. have now become a regularly performed tool in clinical routine. This includes the availability of "problem profiles", "trend analysis", the use of simple concluding statistics as well as the calculation of multivariable models. This internal quality assurance is completed by "multicentric" comparisons with further hospitals already using the same data-base system (external quality assurance). Within 8 years, the feedback-control-system has become a reliable and valuable tool for quality assurance in daily routine. The high acceptance of the database system is related to the advantages it provides for every participant. We conclude that the concept of data evaluation and improvement by means of "output functions" and "integration of data acquisition in clinical routines" has proved to be efficient in everyday practice. The sensitivity and specifity to such a feedback controlled system as a tool for measuring surgical quality, however, still remains a matter requiring further research.