[Material and structure of drainages].

The long history of surgical drainages stands in contradiction to available and reliable data. As of today, closed systems made of silicone are preferable. Taking possible complications into consideration and the good results of routine operations without drainages, indication for use should be critically evaluated. Interdisciplinary research,however, offers the chance of optimizing material and surface characteristics, biostability, biocompatibility, and flow rates. New drainages with improved performance and reduced side effects may counteract the current tendency to do without.