Final answer:
Venting and de-airing the heart during CPB with MIDCAB involves using a cannula for venting and employing de-airing techniques such as carbon dioxide flooding and air aspiration from the heart chambers to prevent air embolism.
Step-by-step explanation:
To vent and de-air the heart during cardiopulmonary bypass (CPB) with Minimally Invasive Direct Coronary Artery Bypass (MIDCAB) surgery, specific steps must be taken to ensure that no air is trapped within the heart that could lead to air embolism when the heart is restarted. It often requires the use of a cannula to vent the left ventricle and the application of de-airing techniques like flooding the surgical field with carbon dioxide and aspirating air from the heart chambers before the aorta is declamped.
This process is crucial for patient safety, as trapped air in the heart can lead to severe complications such as strokes or coronary air embolism. The MIDCAB procedure limits the exposure of the heart, and the de-airing process must be performed with care due to the restricted access.