INTRODUCTION AND EPIDEMIOLOGY
Trauma to an extremity with associated vascular injury has a 5% rate of mortality, 5% rate of primary limb amputation, and 17% rate of delayed limb amputation.1 Penetrating trauma with early shock from proximal arterial hemorrhage is more likely to lead to mortality. Blunt distal extremity trauma with associated distal vascular injury is more commonly involved in early limb loss and amputations. Risk factors for delayed amputation include major soft tissue injury, compartment syndrome, ischemia of more than 6 hours, and associated fracture.2 Injuries involving the lower extremities are more common than injuries involving the upper extremities. The two most commonly injured blood vessels are the femoral and popliteal vessels.3
Advances in diagnostic imaging4 and surgical management have dramatically reduced the rate of limb loss and disability due to limb ischemia.5 The extent of injury to extremity nerves, bones, and soft tissues now determines if the limb can be surgically salvaged. Identifying and detecting which injuries require surgical evaluation and/or imaging are essential skills for emergency physicians.
Gunshot and knife wounds are the two most common causes of penetrating trauma. Stab wounds have a more predictable pattern of injury, making them more straightforward to manage. Gunshot injuries are more difficult to evaluate due to the extent of tissue damage and wider range of patterns of injury. More sophisticated vascular surgical repair techniques of arterial injuries,6 advances made during military conflicts, improved imaging, and other factors have led to a decreased rate of limb amputations and limb disability associated with penetrating trauma.7
Perform the primary trauma survey, immediate resuscitation, and secondary survey before focusing on injuries to the extremities. Apply direct pressure, pressure dressings, or a tourniquet to any actively bleeding extremity (see Chapter 254, “Trauma in Adults”). Do not get distracted or deviate from the initial trauma management because associated injuries to other areas of the body are common with penetrating injuries. After identifying an injury during the secondary survey, thoroughly evaluate the affected extremity for vascular integrity, nerve function, skeletal injury, and soft tissue injury. The rapid evaluation of extremities for associated arterial injury is critically important for the management of these injuries. Note any hard or soft signs of vascular injury (Table 266-1). Use a Doppler flow device to detect a pulse if distal pulses cannot be palpated.
TABLE 266-1Clinical Manifestations of Extremity Vascular Trauma |Favorite Table|Download (.pdf) TABLE 266-1 Clinical Manifestations of Extremity Vascular Trauma
Absent or diminished distal pulses
Obvious arterial bleeding
Large expanding or pulsatile hematoma
Distal ischemia (pain, pallor, paralysis, paresthesias, coolness)