Changes in jugular bulb oxygen saturation during off-pump coronary artery bypass graft surgery

Background: The effect of haemodynamic derangement during coronary artery anastomosis in off-pump coronary artery bypass surgery on cerebral blood flow has not been elucidated. Jugular bulb oxygen saturation is a useful indicator of cerebral blood flow provided that the cerebral metabolic rate is constant. This study was designed to evaluate the changes in jugular bulb oxygen saturation during off-pump coronary artery bypass surgery. Methods: With IRB approval, 48 patients were included. After anaesthesia, an 18-G catheter was introduced into the jugular bulb. Haemodynamic variables and oxygen profiles from gas analysis of jugular bulb blood and arterial blood were obtained: after sternotomy (baseline); at 5 min after the beginning of the anastomosis of the left anterior descending artery, obtuse marginal artery, and right coronary artery; and after sternal closure. Results: Cardiac index and mixed venous oxygen saturation decreased significantly during anastomosis of all three arteries compared to the baseline value. Although the changes in jugular bulb oxygen saturation during anastomosis were statistically significant compared to its baseline value, jugular bulb oxygen saturation remained within normal limit throughout the study. Conclusions: Jugular bulb oxygen saturation, which represents the global cerebral oxygenation, was well maintained during the anastomosis of all coronary arteries despite significant haemodynamic changes during off-pump coronary artery bypass (OPCAB).