Management of Peripheral Vascular Trauma

Introduction

The majority of wartime peripheral vascular trauma are due to explosive mechanisms which result in worse limb salvage rates compared to firearm injuries. Military data suggest that 10% battlefield deaths are secondary to extremity hemorrhage.^[1,2]

The following describes assessment and management of peripheral vascular trauma for emergency scenarios in which a vascular or trauma surgeon is not available and without the availability of endovascular equipment or trained-providers.^[3] With vascular injuries, early recognition and intervention are essential to improve outcomes and functionality, avoid complications, and avert continued hemorrhage, limb loss and mortality.

Initial Assessment

In trauma, assessment of Airway, Breathing, Circulation, Disability, and Exposure (ABCDE) is lifesaving. Intravascular volume repletion is often necessary to avoid shock and for ongoing hemorrhage; whole blood resuscitation is preferred, but any fluid may be lifesaving.

Resuscitation should target a maximum goal systolic blood pressure of 90 mmHg (110 mm Hg if head injury) to avoid further bleeding via clot dislodgement (permissive hypotension).

Pre-screened, type O (or matched) fresh whole blood from a walking donor bank can be used and may be preferred given data from recent experiences in Afghanistan and Iraq.^[4] If no IV pole is available, hand-squeeze or place intravenous bags underneath patients to maintain flow.

Immediate Hemostasis

Significant bleeding is initially best controlled with direct pressure at the bleeding site, wound packing with dry sterile gauze, or tourniquet application (see ‘Stop the Bleed’ videos). Compression should always be applied first. Applying one’s body weight via the knee (if no shrapnel present) to the wound, or just proximal, can control bleeding.

Immediately assess if the limb is salvageable. Application of a tourniquet as distal as possible to prevent blood loss is paramount in maximizing salvageable limb length.

Tourniquets

Analysis of Vietnam War military data found that 7% of combat-related deaths may have been prevented by a tourniquet.^[5] Tourniquets should be used for life-threatening hemorrhage not controlled by direct pressure, packing, or hemostatic agents. Commercially-available tourniquets (e.g. CAT Combat Application Tourniquet) are most effective.

If a commercial tourniquet is not available, improvised tourniquets should consist of three components: a strap, a rod, and a securing mechanism. Straps should be non-stretchable, flexible material 4 to 5 cm wide and at least 50 cm long. Neckties make perfect straps, while most belts are ineffective due to their stiffness. The rod must be rigid and long enough to allow for twisting once knotted to the fabric and strong to endure torque force; metal kitchen utensils such as forks or dinner knives work well. A securing mechanism may be another strip of fabric tied between the strap and rod, duct tape, or a rope to keep the rod from unwinding.

The strap should be placed around the limb and secured with a square knot as distal as possible, approximately 5 cm proximal to the bleed. The rod should then be tied onto the square knot with another square knot prior to twisting the rod sufficiently to stop bleeding. There the rod should be stabilized by the securing mechanism. If bleeding persists, the tourniquet may be occluding veins but not the arteries and should be tightened.

If this is ineffective, a second tourniquet should be placed proximally. Record application time on the tourniquet to document ischemia time. Periodic release of the tourniquets should not be performed. Constriction for >2 hours may result in permanent nerve and muscle injury, and >6 hours will require fasciotomies. Proper tourniquet application is initially very painful. Removal of the tourniquet is discouraged until the patient is in the operating room or a context in which surgical hemostasis is feasible.

Secondary Evaluation

Peripheral vascular injuries are classified as either hemorrhagic or ischemic. Ischemia can result from blunt or penetrating trauma. Blast injuries can cause arterial thrombosis requiring embolectomy and arterial repair with vein patch (detailed below). Reducing a fracture or extremity malalignment with splinting/stabilizing the extremity often improves perfusion. Assess pulses and capillary refill, although this may be abnormal in shock. The first sign of critical ischemia of the limb is sensory loss progressing to loss of muscular activity.

Hard signs of vascular injury are listed in Table 1. They require immediate surgical intervention (except for an arteriovenous fistula).^[3]

Table 1. Hard signs of vascular trauma

Operative Principles for Vascular Trauma

Broad sterile prepping and draping is essential. For the upper extremities this should include from the hand up to the angle of the mandible, across the chest to the contralateral nipple, and down to the umbilicus.^[3]

For lower extremities preparation should extend from the umbilicus down to the feet bilaterally, while covering the genitals, to allow wide access to the injury as well as to the contralateral great saphenous vein (GSV) should an interposition graft or vein patching beneeded. For ongoing hemorrhage, an assistant should hold direct manual pressure over the area of injury while prepping and draping.

The area of injury should be prepped last. In a patient with a ‘cold’ extremity (no pulse, no dopplerable signals), systemic heparinization in the absence of contraindications (intracranial injury, solid organ injury, persistent hemorrhage) should be considered at 80-100 U/kg.^[3]

Artery Exposures

In general, avoid longitudinal, linear incisions over the flexion crease of joint spaces (such as the axillary, brachial, and popliteal fossae). Curvilinear or S-shaped incisions help minimize postoperative contracture.^[3]

If a large, pulsating hematoma is encountered, obtain proximal and distal vascular control through separate longitudinal incisions before connecting the two through the area of injury.^[3] Proximal and distal control should be attained using vascular clamps (Satinsky, DeBakey, Fogarty Hydragrip), bulldog clamps, or silastic vessel loops.

If unable to place a clamp, or there is continued bleeding from the vessel lumen, occlude the vessel with an endoluminal balloon catheter. The following descriptions detail specific exposures.

Upper Extremity Exposures

Axillary Artery: For infraclavicular exposure, place the patient supine with the arm abducted 90° on an armboard. Make a horizontal incision 2 cm below and parallel to the clavicle.^[6] Incise the pectoral fascia and spread the fibers of the pectoralis major to expose the underlying fascia. The axillary sheath lies within adipose tissue deep to this fascia. The axillary vein lies anterior to the artery and should be mobilized and retracted caudally. Mobilize the artery as proximally, taking care to avoid injury to surrounding nerves.

Brachial Artery: Superficial location makes the artery prone to injury, particularly with fracture or dislocation of the humerus. Most injuries are secondary to penetrating trauma with blunt injury often due to humeral dislocation.^[6]  Begin supine with the arm abducted at 90° on an armboard. Avoid hyperextension of the brachial plexus.

The artery lies in the bicipital groove between the axillary and antecubital fossae. Exposure of the artery at the antecubital fossa requires an S-shaped incision starting medially in the upper arm and crossing laterally into the forearm, where the brachial artery often divides into the radial and ulnar artery.

Exposure requires incising the deep fascia at the medial border of the biceps, then opening the brachial sheath. The median nerve is typically more superficial and should be gently retracted anteriorly. The brachial artery runs between two brachial veins laterally and medially with the ulnar nerve posteriorly. To gain control of the artery, ligate crossing vein branches, taking care to avoid injury to nearby nerves.

Lower Extremity Exposures

Femoral Artery: The femoral artery passes under the medial ⅓ of the inguinal ligament before bifurcating into the common femoral artery and profunda femoral artery. Identify the femoral artery via palpation, under ultrasound guidance (the femoral artery runs medial to the femoral nerve and lateral to the femoral vein), or by landmarks if no pulse. Expose the femoral artery via a vertical incision directly over the artery, extending up to the inferior edge of the inguinal ligament.

Dissect through subcutaneous and lymphatic tissue and open the femoral sheath. There are no significant structures between the skin and femoral sheath. Gain control of the common femoral artery. Retract the inguinal ligament cranially for further exposure as necessary. The superficial circumflex iliac vein crosses the artery in this region. Ligate it if/when encountered.

The profunda femoris typically arises 3-5 cm caudal to the inguinal ligament on the posterolateral aspect of the common femoral artery, but often has multiple branches. It is crossed by the lateral femoral circumflex vein which should be ligated to further expose the profunda femoris if needed.

Popliteal Artery: For suprageniculate exposure, in the supine position externally rotate the leg at the hip, slightly flex the knee (30 degrees), and place the leg on a bump (such as OR towels taped together). Incise along the distal third of the medial thigh along the anterior border of the sartorius. Enter the fascia, retract the sartorius posteriorly and the vastus medialis anteriorly to expose the popliteal vessels.

The popliteal artery lies medial to the vein. For infrageniculate exposure, make a longitudinal incision one fingerbreadth posterior to the posterior border of the tibia. Take care to avoid the GSV superficially in this area, which may be marked out prior to incision with ultrasound if available. Incise the crural fascia longitudinally in the same plane as the initial incision proximally. Proximal exposure can be obtained by dividing the pes anserinus – the conjoined tendon of the gracilis, sartorius, and semitendinosus. Retract the medial head of the gastrocnemius posteriorly.

For additional distal exposure divide the tibial attachments of the soleus muscle. The popliteal vein is often paired and overlies the artery. Ligate bridging veins to obtain circumferential control of the popliteal artery. The tibial nerve lies posteromedially and should be avoided.

Repair Techniques

Repair options include ligation, lateral arteriorrhaphy, end-to-end anastomosis, patch repair, or interposition graft. Arteries that can safely be ligated in life-threatening situations: either the radial or ulnar artery (if palmar arch intact), a single tibial artery, internal iliac artery, and the superficial femoral artery if necessary.

Small injuries may be repaired with interrupted 6-0 polypropylene sutures (lateral arteriorrhaphy).

For moderate and large defects, prior to  proximal and distal clamping, administer heparin if available (80-100 U/kg) and the patient has no contraindications (such as intra-abdominal or intracranial bleeding). Pass a Fogarty balloon proximally and distally to remove thrombus prior to repair of the artery. If a Fogarty is not available, tightly wrapping the extremity with an Esmark bandage starting at the fingers/toes and up to the injury works well. Start by debriding the injured artery to healthy arterial wall. Tension-free repair is possible after resection of up to 1–2 cm of vessel, but requires extensive mobilization of the artery proximally and distally. If a moderate defect is present one can perform an end-to-end tension-free anastomosis using 6-0 polypropylene suture in a running fashion. In growing children, one should use interrupted sutures for at least half of the repair to avoid future stenotic complications. If a significant portion of the vascular wall has been injured and primary repair would result in significant narrowing of the vessel lumen, patch angioplasty may be performed (see below for description of contralateral saphenous vein harvest). In the clinically unstable patient, consideration should be taken for ligation, shunting (see below) while the vein is harvested, or prosthetic patch material if available as a last resort.

If a significant defect is present with >2 cm of artery resected, a tension-free anastomosis will not be possible. Interposition grafting will be necessary. Contralateral autogenous vein (e.g. great saphenous vein) is the conduit of choice given lower risk of infection and higher patency compared to prosthetic conduit. However, this requires significant time and should not be attempted in an unstable patient. If available, an assistant may concomitantly harvest the contralateral vein as needed.

If vein is not available, prosthetic such as polytetrafluorethylene (ePTFE) may be used for bypass grafting. This carries a higher incidence of infection and lower patency than vein in below-knee bypasses. The length of a bypass grafts across a joint needs to be measured with the limb in full extension.

To perform a bypass graft anastomosis, use 6-0 polypropylene suture. Description of a vascular anastomosis is detailed in Table 2.

Table 2. Steps in performing a vascular anastomosis

Advanced Techniques

If significant length of artery is resected, a bypass will be needed. Great saphenous vein from the contralateral limb remains the conduit of choice. This is time-consuming and technically challenging intervention. It may be necessary to place a vascular shunt across the area of arterial injury to perfuse the limb and transport to a higher level of care. Descriptions of vascular shunting and vein harvest are detailed below.

Shunting

Shunting may be utilized in ‘damage control’ situations when immediate repair is not feasible. This provides distal perfusion while an extra-anatomic bypass is performed or in the critically unstable patient in hemorrhagic shock in whom definitive repair must be delayed. The major complication of shunting is thrombosis. To mitigate this, care should be taken to select the largest shunt possible.^[3]

The shunt should be 4 cm longer than the space between the two transected ends of the artery to permit 2 cm of the shunt to be inserted proximally and distally. Shunt insertion is detailed in Table 3.

Table 3. Shunt insertion

Shunting is not without risk. Care should be taken to avoid ligation of the popliteal, femoral, or common femoral vein in an extremity with arterial shunting. If ligation of one of these major veins is necessary, shunting should be performed in the vein as well using a size-matched #16-24 Fr thoracostomy tube.^[3]

Thrombosis rates for arterial shunting in civilian vascular trauma is approximately 5%.^[7] The role of heparinization in patients with an intravascular shunt remains controversial. Definitive repair will often require vascular conduit or extra-anatomic bypass given the level of tissue injury from debridement and trauma associated with crushing of the vessel while securing the shunt in place.

Great Saphenous Vein Harvest

When an artery patch or bypass is needed, harvest the contralateral great saphenous vein. The diameter at the ankle is smaller than at the groin, while at the level of the knee it is generally the smallest diameter. For an arterial patch repair the distal segments are most appropriate. For below the knee short bypasses, because of size, the distal vein segment may also be appropriate when reversed.

The great saphenous vein merges into the common femoral vein in the groin, which may be identified using ultrasound. Anatomically, the great saphenous vein can be identified proximally 2 fingerbreadths laterally and 2 fingerbreadths inferiorly from the pubic tubercle.

The vein should be exposed along its length for a distance several cms longer than the necessary bypass length or patch required. All branches should be identified and clipped or ligated with 3-0 silk ties. All ties/clips should be placed far enough from the vein to avoid narrowing the lumen.

Once the vein has been harvested, distend the vein by injecting the vein with heparinized saline and nitroglycerine (~1mg/500cc) if available through a non-sharp intravenous catheter to identify any leaks or untied branches to be repaired. Due to vein valves, this injection and the bypass requires the vein to be reversed, so that blood flow will not be precluded by valves.

Under intraluminal pressure, the anterior surface of the vein should be marked to prevent twisting of the vein during tunneling or the performance of the proximal and distal anastomoses.

Venous Injuries

The most commonly injured veins are the femoral (40%), popliteal (25%) and the common femoral (15%). Venous ligation is typically well-tolerated in the extremities. If there is a small venous defect, or an avulsed side branch, one may perform lateral venorrhaphy/repair using 6-0 prolene.

Generally, the walls are friable when injured and do not tolerate repair.  When venous injury is known or suspected, preserving the ipsilateral saphenous or superficial vein is of paramount importance. Keeping the limb elevated above the heart to decrease edema postoperatively is very beneficial.

Fasciotomy and Post-Revascularization

In vascular injury/repair of the lower extremity in a wartime scenario, nearly all patients should undergo prophylactic 4-compartment fasciotomy. Many have associated, though occasionally not identified, venous injury, develop swelling from associated blast/projectile soft tissue injury and cannot be closely followed post-procedurally all which may lead to compartment syndrome that may not be readily identified or be able to be treated.

Following revascularization, assess for return of normal distal pulses or improved Doppler signals. If there is a large soft tissue defect, muscle or soft tissue coverage of the artery is imperative. Superficial wound dressings or a vacuum dressing can be used. Limb elevation above the level of the heart is helpful to decrease swelling.

Non-Salvageable Extremity

In a non-salvageable extremity, amputate to avoid further blood loss, morbidity, and mortality. Compared to firearm injuries, injuries from explosives have higher rates of primary amputation (13% vs 2%), secondary amputation (13% vs 2%), and lower long-term freedom from amputation (67% vs 89%).^[9]

Upper extremity vascular injuries are associated with low risk of amputation (~1%), although this rate significantly increases if the brachial artery is ligated (18-55%). Lower extremity vascular injuries have an amputation rate of 11%. This increases up to 70% with delayed presentation.^[1] The following outlines operative techniques for lower extremity amputations.

Guillotine Amputation

Guillotine amputation of the foot may be used if the wound is dirty or infected in a non-salvageable foot. Place the patient in Trendelenburg position to allow for venous drainage prior to amputation. Cut straight down through tissue to the bone above the malleoli at the ankle. This should be done as the assistant is tightly constricting the leg at the distal calf to avoid blood loss.

Use electric bone saw or Gigli saw for encountered bone. Tie off arteries, veins, and nerves with 2-0 vicryl or silk ties while suture-ligating larger vessels. Once hemostasis has been obtained, pack with dry sterile gauze and wrap. Daily dressing changes are needed or should be performed for saturated dressings. A completion below-knee or above-knee amputation may be performed after several days.

Higher level guillotine amputation can be done through the knee if the calf is not salvageable. In these instances, the skin should be incised at the level of the tibial tuberosity to provide adequate skin coverage for an eventual “through knee amputation”. The insertion of the patella should be excised from the tibia and the knee capsule and the ligaments are sharply transected. Posteriorly, the popliteal artery, veins and tibial nerve are transected and doubly ligated. The vessels are covered and the wound can be dressed for staged through-knee amputation.

Complications

Postoperative complications associated with vascular repair in a patient presenting with peripheral vascular trauma include compartment syndrome (see section on fasciotomies in separate module), rhabdomyolysis, and reperfusion injury. Care should be taken to monitor closely for these potential complications and treat accordingly. As long as perfusion is adequate, elevation of the limb to a level above the heart is important for decreasing the edema.

Conclusion

Peripheral vascular trauma remains a challenging entity for surgeons operating in war and conflict regions. Expedient management of hemorrhage and prompt revascularization is essential for preservation of life and limb.

Clinical Take-Aways

• In a patient with severe polytrauma to abdomen or chest as well as to an extremity, tourniquet the extremity and address the life-threatening injury elsewhere. If able to repair the peripheral vascular injury afterwards, remember to perform an appropriate fasciotomy.
• If primary repair would narrow the artery a vein patch should be performed.
• If the injury is not amenable to primary repair or patch, a size-matched shunt should be inserted to allow time for addressing additional injuries, resuscitation, triage of other casualties, and/or transferring the patient to a higher level of care.
• When attempting arterial repair using a graft, use reversed vein harvested from an uninjured extremity if possible (preferably a great saphenous vein, but cephalic vein can be considered for short bypasses) or PTFE for larger caliber arteries such as the common femoral artery as needed.
• Ligating veins distal to the axilla in the arm and distal to the profunda-femoral vein confluence in the lower extremities is safe if necessary in damage control situations.
• Concerning concomitant major vascular, bone, and soft tissue injuries, if the extremity is mangled beyond repair, the patient would not tolerate multiple takebacks for extremity reconstruction, or resources do not allow for multiple takebacks then amputation is advised.
• Completely insensate feet or lower extremities do not fare as well as prosthetic limbs. Salvage of insensate lower extremities is not advisable.

Citations

1. Herrera MA, Millán M, Del Valle AM, Betancourt-Cajiao M, Caicedo Y, Caicedo I, et al. Damage control of peripheral vascular trauma – Don’t be afraid of axillary or popliteal fosses. Colomb Med. 2021 Apr 10;52(2):e4074735.
2. Champion HR, Bellamy RF, Roberts CP, Leppaniemi A. A profile of combat injury. J Trauma. 2003 May;54(5 Suppl):S13–9.
3. Feliciano DV. Pitfalls in the management of peripheral vascular injuries. Trauma Surg Acute Care Open. 2017 Aug 28;2(1):e000110.
4. Strandenes G, De Pasquale M, Cap AP, Hervig TA, Kristoffersen EK, Hickey M, et al. Emergency whole-blood use in the field: a simplified protocol for collection and transfusion. Shock. 2014 May;41 Suppl 1:76–83.
5. Bellamy RF, Zajtchuk R, Grande CM. Combat trauma overview. Textbook of military medicine part IV: surgical combat casualty care: anesthesia and peri‐operative care of the combat casualty. 2005;1–42.
6. Wind GG, James Valentine R. Anatomic Exposures in Vascular Surgery. Lippincott Williams & Wilkins; 2013. 608 p.
7. Subramanian A, Vercruysse G, Dente C, Wyrzykowski A, King E, Feliciano DV. A decade’s experience with temporary intravascular shunts at a civilian level I trauma center. J Trauma. 2008 Aug;65(2):316–24; discussion 324–6.
8. Johansen K, Daines M, Howey T, Helfet D, Hansen ST Jr. Objective criteria accurately predict amputation following lower extremity trauma. J Trauma. 1990 May;30(5):568–72; discussion 572–3.
9. Sharrock AE, Tai N, Perkins Z, White JM, Remick KN, Rickard RF, et al. Management and outcome of 597 wartime penetrating lower extremity arterial injuries from an international military cohort. J Vasc Surg. 2019 Jul;70(1):224–32.