Cross-clamping the thoracic aorta

Access to the thoracic aorta is best achieved by incising the parietal pleura overlying the aorta and retracting the lung anteriorly. Blunt dissection is used to develop a space between the esophagus and aorta to permit aortic cross-clamping above the diagphragm without damaging the intercostal vessels. When the aorta is collapsed, as in the hypotensive patient, palpation of the naso- or orogastric tube can aid in differentiating the esophagus from the aorta.