Treatment of the infection in deep sternal wound infections-a single center cohort study.

Background: In the treatment of deep sternal wound infections (DSWIs) using negative pressure wound therapy (NPWT), infection therapy is separated from reconstruction of the thoracic wall. It is difficult to decide when NPWT can end in order to close the wound. Often ideal conditions cannot be achieved. Must or can sterility be waited for and should antibiotics be administered and if so for how long? These questions are discussed here. Methods: A retrospective single center analysis is performed. Patients who developed a DSWI after cardiac surgery between 2014 and 2020 are included. The following parameters are collected: baseline data, number of negative pressure dressing changes, frequency of persistence of infection and antibacterial therapy performed at closure. Either a short-term antibiotic therapy over 5 days or a therapy corresponding to the osteomyelitis treatment over 6 weeks was carried out. Results: In 79 patients, sterility was achieved after 10.2±3.9 (mean ± standard deviation) changes of the negative pressure dressing using NPWT. In 51 patients, NPWT was terminated after 7.4±5.3 changes without achieving sterility. The number of changes varied significantly. If sterility could be achieved, the frequency of infection complications was significantly lower. Long-term antibiotic therapy resulted in significantly fewer infections than short-term therapy. Conclusions: Microbiological sterility should be achieved if possible. This requires more dressing changes, but the complications are rarer. If it is not possible to wait for sterility, long-term antibiotic therapy is required if osteomyelitis occurs.