The fascia plane of the neck is directly connected to the anatomical plane of the upper mediastinum and the organ space. The structure and plane of the lower mediastinum are also connected to the upper part of the retroperitoneum through the fascia. Infection originating from the space of one area of the upper surgery can directly enter another anatomical area through this anatomical area. In particular, infections originating from the neck are not only due to gravity, but also due to the negative pressure of the chest cavity that spreads downward into the mediastinum. From an anatomical point of view, the above spaces and channels include the retropharyngeal space, the pretracheal space, the retrosternal space, the cervical vascular sheath, and the space around the esophagus. In recent years, the number of cases of median sternotomy for cardiovascular surgery has increased, and the incidence of postoperative mediastinal infection has also increased accordingly.