Carbon dioxide embolism during endoscopic saphenous vein harvesting in coronary artery bypass surgery

Objectives: Our objectives were to determine the incidence and severity and the time course of the CO2 embolism during endoscopic saphenous vein harvesting with CO2 insufflation in coronary artery bypass surgery with transesophageal echocardiography monitoring. Methods: Four hundred three consecutive patients scheduled for off-pump coronary artery bypass grafting surgery or femoral-to-popliteal artery bypass grafting surgery were prospectively studied. Multiplane transesophageal echocardiography with a new transgastric view was used to monitor CO2 bubbles in the inferior vena cava and hepatic vein. Results: CO2 embolisms occurred in 17.1% of patients. Minimal, moderate, and massive CO2 embolisms occurred in 13.1%, 3.5%, and 0.5%, respectively. The occurrence of moderate and massive CO2 embolisms was frequently associated with the surgical manipulation of branches of saphenous veins. No significant risk factors were identified in multiple logistic regression analysis. Conclusion: The incidence of significant CO2 embolism during endoscopic saphenous vein harvesting with CO2 insufflation procedures was more than 4%. Continuous transesophageal echocardiographic monitoring of the CO2 bubbles in the inferior vena cava is essential in early detection and can help to prevent the development of significant CO2 embolisms in these patients.