Deep median sternotomy wound infection is a significant source of morbidity and mortality after open cardiac surgery. 
Between January 1994 and May 2001, 600 open-heart procedures using median sternotomy and cardiopulmonary bypass were performed in Mansoura Cardiothoracic Surgery Department. A total of 28 patients (4.6%) with deep sternotomy wound infection were identified. 
Most of these infections were associated with a number of risk factors such as prolonged preoperative hospital stay 
(75% P<0.001), obesity (68% P<0.05), diabetes mellitus (54% P<1.001), prolonged operative time (71% P<0.001), prolonged cardiopulmonary bypass (68%, P<0.05), prolonged ventilation, (75% P<0.05) and reexploration for control of bleeding or tamponade (32% P<0.001). Most of these infections were caused by staphylococcus aurous (46.4%). To study the risk factors for mediastinitis, the patients were divided into 2 groups, group I (Mediastinitis group, 28 patients) and group II (Control group, 28 consecutive mediastinitis free patients). 
For the evaluation of the effective surgical procedure in the mediastinitis group, infected patients were further subdivided into 2 subgroups, subgroup A (open technique) and subgroup B (closed technique). 
In the open technique we open the wound and dress it three times daily for about 2 weeks until the wound becomes clean with healthy granulation tissue then reclosure of the sternum after debridement using Bonecheck technique. In the closed technique we close the sternum using Boneckeck technique after debridement with closed irrigation system using diluted betadine solution. The overall mortality in our mediastinitis group of patients was 25%. It was more in the open technique (44.4%) than in the closed technique (15.8%), (P < 0.001 Hs) We conclude that, careful preoperative preparation, rapid surgical technique with careful haemostasis and strong perioperative antibiotics are required to reduce the incidence of mediastinitis. Early treatment under coverage of strong antibiotics debridement and closed irrigation system with proper reclosure of the sternum by Bonecheck technique improve the sternal stability and reduce the morbidity and mortality than the open technique.