#Repair of Veins.#--The process of repair in veins is the same as that in arteries, but the thrombosed area may become canalised and the circulation through the vessel be re-established. HÆMORRHAGE IN SURGICAL OPERATIONS The management of the hæmorrhage which accompanies an operation includes (a) preventive measures, and (b) the arrest of the bleeding. #Prevention of Hæmorrhage.#--Whenever possible, hæmorrhage should be controlled by _digital compression_ of the main artery supplying the limb rather than by a tourniquet. If efficiently applied compression reduces the immediate loss of blood to a minimum, and the bleeding from small vessels that follows the removal of the tourniquet is avoided. Further, the pressure of a tourniquet has been shown to be a material factor in producing shock. In selecting a point at which to apply digital compression, it is essential that the vessel should be lying over a bone which will furnish the necessary resistance. The common carotid, for example, is pressed backward and medially against the transverse process (carotid tubercle) of the sixth cervical vertebra; the temporal against the temporal process (zygoma) in front of the ear; and the facial against the mandible at the anterior edge of the masseter. In the upper extremity, the subclavian is pressed against the first rib by making pressure downwards and backwards in the hollow above the clavicle; the axillary and brachial by pressing against the shaft of the humerus. In the lower extremity, the femoral is controlled by pressing in a direction backward and slightly upward against the brim of the pelvis, midway between the symphysis pubis and the anterior superior iliac spine. The abdominal aorta may be compressed against the bodies of the lumbar vertebræ opposite the umbilicus, if the spine is arched well forwards over a pillow or sand-bag, or by the method suggested by Macewen, in which the patient's spine is arched forwards by allowing the lower extremities and pelvis to hang over the end of the table, while the assistant, standing on a stool, applies his closed fist over the abdominal aorta and compresses it against the vertebral column. Momburg recommends an elastic cord wound round the body between the iliac crest and the lower border of the ribs, but this procedure has caused serious damage to the intestine.