What holds the dacron tube in place after thoracic replacement surgery?

After a thoracic replacement surgery, the dacron tube is sewn in. The surgery involves stitching it to the remaining parts of the bronchi and the heart with sutures. The surgical team can also opt for a procedure known as cardiopulmonary bypass. This involves stitching a tube to the aortic arch, left lower pulmonary artery, and pulmonary artery in order to redirect the blood during surgery. The aorta and main pulmonary artery are cross-clamped before circulation is stopped. The heart then is kept functioning on a heart-lung machine.