Describe the DistaE Dissection Techniques of Surgery?

DistaE Dissection (De Bakey Type ZII or Stanford Type B) :  Techniques of Surgery :  The approach is through a left posterolateral thoracotomy with anaesthesia being given through a double lumen endobronchial tube. Left femoral artery and Pein are cannulated for initiation of femoro femoral bypass. Usually the dissection starts beyond left subclavian artery. Proximal control should be just distal to left subclavian artery or between left carotid and subclavian artery. When there is retrograde dissection to the arch, profound hypothermia and circulatory arrest will have to be utilised for repair. Clamps are applied above and below the area of proposed resection. Aorta is opened longitudinally and control of inter costal arterial openings are done as in resection of aneurysm of descending thoracic aorta. Aorta is transacted proximally. If the layers of aorta are separated they are approximated between strips of PTFE felt and resulting cuff is anastomosed to the end of the vascular graft. After anastomosis the proximal clamp is removed, reapplied on the graft and proximal anastomotic site checked for bleeding. Similarly the distal aorta is transacted and if dissections extend beyond, cuff is prepared by suturing the two layers with reinforcement using PTFE felt. Air is removed from the graft and clamps removed and circulation restored. After discontinuing by pass and decannulation, protamine is given to reverse heparin. After haemostasis chest is closed with two drains.