Localized Pulmonary Edema in the Middle and Inferior Lobes of the Right Lung after One-lung Ventilation for Minimally Invasive Mitral Valve Surgery

Fiberoptic bronchoscopy revealed an ectopic tracheal bronchus to the right upper lobe arising 3 cm above the carina. An endobronchial blocker (COOPDECH™, Osaka, Japan) was positioned in the proximal right intermediate bronchus, blocking the middle and inferior lobes. Although the right upper lobe was ventilated, it did not obstruct the surgical field via a right anterior thoracotomy. The patient was ventilated using pressure-control ventilation with inspiratory pressure 20 cm H2O, positive end-expiratory pressure (PEEP) 6 cm H2O, and tidal volume 500 mL at an FIO2 1.0 after collapse of the right middle and lower lobes. The femoral artery was cannulated with a 20-Fr arterial cannula and the femoral vein with a 28-Fr venous cannula positioned into the right atrium with the tip in the superior vena cava to establish CPB. An antegrade cardioplegia cannula was inserted into the ascending aorta with a flexible cross-clamp subsequently applied. The heart was arrested initially by using antegrade cold blood cardioplegia. Myocardial protection was provided using mild systemic hypothermia (341C), and antegrade cold blood cardioplegia was given throughout the procedure at 30-minute intervals.