[Early and long-term results of treatment for infected deep sternotomy wounds]

A retrospective study and follow-up was undertaken to determine the optimal treatment of poststernotomy wound infections. Between January 1990 and April 2000 mediastinitis developed in 62 patients following 7458 heart operations (0.83%). Median age of 50 males and 12 females was 59.1 +/- 9.1 years (27-77). Mediastinal infections occurred within 14.2 +/- 10.9 days (3-90) following cardiac surgery. Most common symptoms and clinical findings were purulent wound drainage or dehiscence (50%), sternal instability (46.7%) and fever (35.5%). Most commonly isolated pathogens were Staphylococcus aureus and coagulase-negative Staphylococci which alone or together with other Gram-positive bacteria caused nearly 70% of all infections. Following the exploration and radical debridement, the wounds in two patients were left to heal by open granulation, 26 patients were initially treated by closed mediastinal suction--or irrigation, and 43 patients were treated with muscle and/or omental flap transposition (34 primarily, 9 following the failure of other methods). Recurrence of infections occurred in 16 patients: 10 from the "closed treatment" group (38.5%) and 6 from the "soft tissue flap" group (14%). Nine patients died during the hospital stay. The mortality rate was 15.4% following the closed method (4/26) and 14.7% following the treatment with flap reconstructions (5/34). There were 6 late deaths, non-related to recurrent infection. Healed wounds were obtained in 96.2% of all patients. About one third of patients noted continuous or intermittent chest pain or discomfort in the closed and the soft tissue flap transposition group. 22.6% of patients claimed sternal instability and 9.7% shoulder weakness--each of them underwent muscle and/or omental flap closure. Abdominal hernias or bulges were present in 4 patients (12.9%) following the use of abdominal flap for wound reconstruction. These results suggest that early debridement and closed method would be successful when employed soon after cardiac surgery. When reexploration is delayed for any reason or obvious extensive involvement of bone or cartilage is present, the wound should be reopened, debrided and treated with muscle and/or omental flaps. Patients in whom closed method fails could probably treated with soft tissue flap transposition soon after the reoperation. Long-term results of closed mediastinal drainage or lavage and flap closure are favourable to open granulation technique regarding wound healing and elimination of infection.