Pulmonary collapse alone provides effective de-airing in cardiac surgery: a prospective randomized study.
OBJECTIVE
We previously described and showed that the method for cardiac de-airing involving: (1) bilateral, induced pulmonary collapse by opening both pleurae and disconnecting the ventilator before cardioplegic arrest and (2) gradual pulmonary perfusion and ventilation after cardioplegic arrest is superior to conventional de-airing methods, including carbon dioxide insufflation of the open mediastinum. This study investigated whether one or both components of this method are responsible for the effective de-airing of the heart.


METHODS
Twenty patients scheduled for open, left heart surgery were randomized to two de-airing techniques: (1) open pleurae, collapsed lungs and conventional pulmonary perfusion and ventilation; and (2) intact pleurae, expanded lungs and gradual pulmonary perfusion and ventilation.


RESULTS
The number of cerebral microemboli measured by transcranial Doppler sonography was lower in patients with open pleurae 9 (6-36) vs 65 (36-210), p = 0.004. Residual intra-cardiac air grade I or higher as monitored by transesophageal echocardiography 4-6 minutes after weaning from cardiopulmonary bypass was seen in few patients with open pleurae 0 (0%) vs 7 (70%), p = 0.002.


CONCLUSIONS
Bilateral, induced pulmonary collapse alone is the key factor for quick and effective de-airing of the heart. Gradual pulmonary perfusion and ventilation, on the other hand, appears to be less important.
Department of Cardiothoracic Surgery, Anesthesia and Intensive Care, Skane University Hospital, Lund University, Lund, Sweden maya.landenhed@med.lu.se.
Maya
M
Landenhed
Department of Cardiothoracic Surgery, Anesthesia and Intensive Care, Skane University Hospital, Lund University, Lund, Sweden.
Doris
D
Cunha-Goncalves
Department of Cardiothoracic Surgery, Anesthesia and Intensive Care, Skane University Hospital, Lund University, Lund, Sweden.
Faleh
F
Al-Rashidi
Department of Cardiothoracic Surgery, Anesthesia and Intensive Care, Skane University Hospital, Lund University, Lund, Sweden.
Leif
L
Pierre
Clinical Research and Competence Center, Skane University Hospital, Lund University, Lund, Sweden.
Peter
P
Höglund
Department of Cardiothoracic Surgery, Anesthesia and Intensive Care, Skane University Hospital, Lund University, Lund, Sweden.
Bansi
B
Koul
D000368:Aged; D000369:Aged, 80 and over; D006348:Cardiac Surgical Procedures / Q000379:methods*; D005260:Female; D006801:Humans; D008168:Lung / Q000098:blood supply / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D001261:Pulmonary Atelectasis; D012121:Respiration, Artificial / Q000379:methods*; D014692:Ventilation-Perfusion Ratio
aortic valve/replacement; cardiopulmonary bypass; surgery/techniques; ultrasound