A 46-year-old man underwent redo bilateral sequential lung transplantation for rapidly progressive bronchiolitis obliterans syndrome that developed 3.5 years after initial transplantation. In the operating room, he was sedated and intubated with a dual lumen endotracheal tube with subsequent single right-lung ventilation and left allograft implantation. His pulmonary arterial pressure became elevated with reperfusion of the newly implanted left lung, which required initiation of cardiopulmonary bypass to facilitate implantation of the right lung. After implantation and reperfusion of the right lung, the patient was weaned from cardiopulmonary bypass. His chest was closed and he was transferred to the thoracic intensive care unit. On arrival to the intensive care unit, the patient was intubated, sedated, and had an oxygen saturation of 92% on a fraction of inspired oxygen of 100%, positive end-expiratory pressure of 10 cm H2O, and 20 parts per million of inhaled nitric oxide. He had a Swan-Ganz catheter in the right internal jugular vein that measured a mean pulmonary arterial pressure of 33 mm Hg and a pulmonary arterial systolic pressure of 63 mm Hg, which remained persistently elevated and prompted further diagnostic evaluation.