2. Mechanism
Penetrating Injury
• Focal
• Stab, gunshot, IV drug abuse
• Low/High velocity
Blunt Injury
• Diffuse adjacent to bone,
muscle, nerve, collateral vessel
• Joint displacement, bone
fracture, contusion
3. Patophysiology
• Trauma to a blood vessel (artery or vein) hemorrhage, thrombosis, or
spasm, either alone or
• Hemorrhage occurs when there is a laceration or puncture of all of three
layers.
• If the bleeding is tamponaded by the surrounding tissue (ie, muscle or
fascia), a localized hematoma will form, which may be pulsatile.
• Intimal injury exposes the subendothelial matrix, which is rich in tissue
factor, resulting in activation of the clotting cascade and subsequent
thrombus formation.
• The thrombus may enlarge or propagate and occlude the vessel or
embolize and produce a distal occlusion.
• The injured intima may also form a flap that can prolapse into the arterial
lumen as a result of the forward blood flow dissecting under it
6. Management
Operative
• Operative therapy is required for thrombosis, ischemia (including
ischemic “steal” produced by an enlarging arteriovenous fistulae), and
failure of small pseudoaneurysms to resolve.
11. Pre-Operative Preparation
• Broad-spectrum antibiotics and tetanus toxoid
• Systemic unfractionated heparin should be administered 70 U/kg) as
soon as possible after the diagnosis of ischemia is made.
• 5000 IU UFH/500mL regional injection
• Clear thrombus Fogarty catether
12. Post-Operative Care
• Monitor distal arterial pulses
• Continue IV antibiotics for 24 hours if contamination of wound or if
interposition graft is inserted
• Conseider use of antiplatellet agent for 3 months if vein graft or
synthetic graft is inserted
13. Heparinization
• Unfractioned Heparin
• dilute 25,000 units of heparin to 50mls (25,000 units heparin in 5mls
and 45mls of 0.9% sodium chloride) to produce a concentration of
500 units/ml. Administer via a syringe pump.
• Start the infusion at 2mls/hour (1,000 units/hour)
• Check APTT ratio/APTT (sec) 4 hours after infusion start.
Vessel disruption is the commonest vascular injury and may
be partial or complete. Partial disruptions usually cause active
bleeding if an open wound is close to the disruption. It may present
as an expanding or pulsatile haematoma (Figure 2). Partial
disruptions may not present with ischaemia because a channel
for blood flow can be maintained. False aneurysms may develop
if a partial disruption is unrecognized. Complete disruptions
usually
present with haemorrhage, which decreases as the vessel
goes into spasm and a clot develops (Figure 3).
Intimal injuries are the second commonest type of vascular
injury and may lead to thrombosis of the vessel or the formation
of an intimal flap, progressing to distal ischaemia. Occasionally,
an intimal flap may cause a dissection, which extends with time
and may become apparent later.
Arteriovenous fistula formation occurs if an artery and its adjacent
vein are injured. They are commonly seen after penetrating
trauma and tend to present late.
Arterial spasm is rare and should not be considered as the cause
of limb ischaemia after trauma.
An interposition graft is used if vessel ends cannot be approximated without tension.
A reversed long saphenous vein is of sufficient calibre to replace vessels up to the superficial femoral artery in size. If a vein is not available, prosthetic grafts made out of expanded polytetrafluoroethylene are used because they are resistant to infection.
