Comparative Effectiveness of Unilateral vs. Bilateral Pulmonary Collapse in Cardiac De-airing

Effective removal of air from the heart before termination of cardiopulmonary bypass (CPB) is vital in open left heart surgery. Bilateral collapse of the lungs during cardiopulmonary bypass decreases the duration of the de-airing procedure, decreases residual air emboli monitored on Trans-esophageal Echocardiography (TEE) and decreases gaseous cerebral microemboli (MES) monitored by Trans-cranial Echo-Doppler (TCD) when compared to expanded lungs during (CPB). Induced pulmonary collapse by opening of the pleura and disconnection of the patient from the ventilator during CPB decreases the amount of air that can enter the pulmonary veins. Not all surgeons wish to induce lung collapse from fraught that it might lead to pulmonary ischemia or infection. It is unknown whether collapse of only the right lung is as effective as collapse of both lungs.