INJURIES OF ARTERIES
Peripheral vascular injuries may result from penetrating or blunt trauma to the extremities. If not recognized and treated rapidly, injuries to major arteries, veins, and nerves may have disastrous consequences resulting in the loss of life and limb.
A direct injury of a large artery of the limb, e.g., the brachial or femoral artery may produce- contusion or partial or complete rupture of the arterial wall which can cause immediate localized arterial spasm (traumatic segmentary arteriospasm). Arteriospasm is commonly seen in fracture of the limb bone, and occurs when the bone ends or fragments contuse or lacerete an artery.
Contusions of the arteries are usually found in the intima, and are usually associated with tears of the intima and thrombus formation. Arterial contusions are common in crush injuries of the limbs. When an artery is lacerated or punctured, e.g., by a bone fragment or by a bullet, a perivascuiar haematoma may form in the surrounding tissues. The blood at the periphery of the haematoma may coagulate and organize, and if the central portion of the haematoma remains fluid, a direct communication may be maintained between the artery and the haematoma forming a false aneurysm.
This aneurysm may gradually increase in size and rupture resulting in profuse haemorrhage and death. True traumatic aneurysms are rare. It may occur when outer coat of a large artery is injured, e.g., a tangential bullet injury of a vessel. A penetrating wound of a limb, e.g. from a pointed weapon or bullet may pass through an artery and the accompanying vein producing an arteriovenous fistula.
In the rare instance of a patient who undergoes operative treatment for a blunt injury to carotid or vertebral arteries, the operative and postoperative principles for penetrating arterial injuries should be applied
In the upper extremity, the areas of greatest concern include the axilla and the area from the deltopectoral groove distally across the elbow to the proximal forearm. The axilla, medial and anterior upper arm, and antecubital fossa particularly are considered high-risk areas because of the superficial location of the axillary and brachial arteries in these regions.
The adhesive interaction between endothelial P-selectin and leukocyte SLeX may play an important role in endothelial injuries of the coronary artery distal to the thrombotic site.The functional and morphological injuries of the endothelium with adhered leukocytes and the upregulated P-selectin expression on the endothelium of coronary arteries distal to the thrombotic site after developing CFVs.
Muscle damage may be spotty, with areas of viable and nonviable muscle found in the same muscle group. Periosteal muscle damage may occur even though overlying muscle appears to be normal. This injury is usually most severe in the small muscle branches, where blood flow is slower. This damage to small arteries in muscle, combined with mixed muscle viability that is not visible to gross inspection, creates the illusion of "progressive" tissue necrosis.
Musculoskeletal injuries include fractures, joint dislocations, ligament sprains, muscle strains, and tendon injuries. Injuries may be open (in communication with a skin wound) or closed. Some injuries can cause rapid blood loss that is sometimes internal.The greatest threat to a limb is from injuries that impair vascular supply, primarily by direct injury to arteries or occasionally to veins. Closed injuries can cause ischemia by arterial disruption, as can occur in posterior knee dislocations, hip dislocations, and displaced supracondylar humeral fractures.