Coronary Artery Bypass Surgery - Procedure (simplified)

Procedure (simplified)

1. The patient is brought to the operating room and moved on to the operating table.
2. An anaesthetist places a variety of intravenous lines and injects a painkilling agent (usually fentanyl) followed within minutes by an induction agent (usually propofol) to render the patient unconscious.
3. An endotracheal tube is inserted and secured by the anaesthetist and mechanical ventilation is started. General anaesthesia is maintained by a continuous very slow injection of Propofol.
4. The chest is opened via a median sternotomy and the heart is examined by the surgeon.
5. The bypass grafts are harvested – frequent conduits are the internal thoracic arteries, radial arteries and saphenous veins. When harvesting is done, the patient is given heparin to prevent the blood from clotting.
6. In the case of "off-pump" surgery, the surgeon places devices to stabilize the heart.
7. If the case is "on-pump", the surgeon sutures cannulae into the heart and instructs the perfusionist to start cardiopulmonary bypass (CPB). Once CPB is established, the surgeon places the aortic cross-clamp across the aorta and instructs the perfusionist to deliver cardioplegia (a special potassium-mixture, cooled) to stop the heart and slow its metabolism. Usually the patient's machine-circulated blood is cooled to around 84 °F (29 °C)
8. One end of each graft is sewn on to the coronary arteries beyond the blockages and the other end is attached to the aorta.
9. The heart is restarted; or in "off-pump" surgery, the stabilizing devices are removed. In cases where the aorta is partially occluded by a C-shaped clamp, the heart is restarted and suturing of the grafts to the aorta is done in this partially occluded section of the aorta while the heart is beating.
10. Protamine is given to reverse the effects of heparin.
11. Chest tubes are placed in the mediastinal and pleural space to drain blood from around the heart and lungs.
12. The sternum is wired together and the incisions are sutured closed.
13. The patient is moved to the intensive care unit (ICU) to recover.
14. Nurses in the ICU focus on recovering the patient by monitoring blood pressure, urine output and respiratory status as the patient is monitored for bleeding through the chest tubes. If there is chest tube clogging, complications such as cardiac tamponade, pneumothorax or death can ensue. Thus nurses closely monitor the chest tubes and under take methods to prevent clogging so bleeding can be monitored and complications can be prevented.
15. After awakening and stabilizing in the ICU (approximately one day), the person is transferred to the cardiac surgery ward until ready to go home (approximately four days).