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

Comparative Effectiveness of Unilateral Versus Bilateral Pulmonary Collapse in De-airing During Open Left Heart Surgery.

To compare the effectiveness of unilateral pulmonary collapse (right lung) to bilateral pulmonary collapse for cardiac de-airing in open left-sided heart surgery.

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.

Cerebral air emboli will be assessed quantitatively by On-line counting of gaseous microembolic signals (MES) by Trans-cranial Echo-Doppler (TCD) monitoring of the right and left middle cerebral artery. The sum of the gaseous microembolic signals registered from the right and the left middle cerebral artery will be reported.

Cerebral air emboli will be assessed quantitatively by On-line counting of gaseous microembolic signals (MES) by Trans-cranial Echo-Doppler (TCD) monitoring of the right and left middle cerebral artery. The sum of the gaseous microembolic signals registered from the right and the left middle cerebral artery will be reported.

Cerebral air emboli will be assessed quantitatively by On-line counting of gaseous microembolic signals (MES) by Trans-cranial Echo-Doppler (TCD) monitoring of the right and left middle cerebral artery. The sum of the gaseous microembolic signals registered from the right and the left middle cerebral artery will be reported.

Number of Participants With <=Grade I Air Emboli as Assessed by Trans-esophageal Echocardiography (TEE) After Finished De-airing.

The severity of residual air emboli in three anatomic areas; left atrium, left ventricle and the aortic root, is assessed by Trans-esophageal Echocardiography (TEE) and classified in grade 0-3 as follows: Grade 0: no residual air emboli, Grade I: air emboli observed in one of three anatomic areas, Grade II: air emboli observed simultaneously in two of three anatomic areas, Grade III: air emboli observed simultaneously in all three anatomic areas.

Number of Participants With <=Grade I Air Emboli as Assessed by Trans-esophageal Echocardiography (TEE) After Finished De-airing.

The severity of residual air emboli in three anatomic areas; left atrium, left ventricle and the aortic root, is assessed by Trans-esophageal Echocardiography (TEE) and classified in grade 0-3 as follows: Grade 0: no residual air emboli, Grade I: air emboli observed in one of three anatomic areas, Grade II: air emboli observed simultaneously in two of three anatomic areas, Grade III: air emboli observed simultaneously in all three anatomic areas.

Number of Participants With <=Grade I Air Emboli as Assessed by Trans-esophageal Echocardiography (TEE) After Finished De-airing.

The severity of residual air emboli in three anatomic areas; left atrium, left ventricle and the aortic root, is assessed by Trans-esophageal Echocardiography (TEE) and classified in grade 0-3 as follows: Grade 0: no residual air emboli, Grade I: air emboli observed in one of three anatomic areas, Grade II: air emboli observed simultaneously in two of three anatomic areas, Grade III: air emboli observed simultaneously in all three anatomic areas.

Duration in minutes fråm removal of the aortic cross clamp to finished de-airing, an average of 10-15 minutes.

Inclusion Criteria: Aortic valve pathology requiring surgery. Exclusion Criteria: Prior thoracic surgery, Severe chronic obstructive pulmonary disease and/or Emphysema.