Introduction
The principles of assisting at cardiac and thoracic surgical operations are no different from those of other specialties. Maintenance of a stable, bloodless and well exposed operative field is the primary goal. This is much more easily achieved in cardiac than in thoracic surgical procedures, thanks to the aid of a cardiopulmonary bypass pump, minimal blood in the field, and a still heart. By contrast, in thoracic surgical procedures the assistant and surgeon must contend with mobile lung tissue, a beating heart and a continuously shifting mediastinum due to ventilation on the non–operated lung. As with other surgical specialties, your role as the assistant is crucial in maintaining the ideal environment for the surgeon to complete his or her procedure effectively.
It is important that the patient's investigations are available pre–operatively for the surgeon to review. In particular, if a coronary artery bypass is to be performed, the patient's angiogram results (and preferably, the films themselves) should be available. In thoracic surgery, the patient's chest X–rays and/or thoracic CT scans should be available.
Assisting at cardiac surgery
The median sternotomy
The median sternotomy is by far the commonest incision for heart operations. It involves making a vertical skin incision from just below the sternal notch down to the xiphisternum. Once the skin is incised, only subcutaneous fat remains to be divided before the periosteum of the sternum is reached. The surgeon will score the sternal periosteum from the top of the manubrium down to the xiphisternum and will divide the xiphisternum.