Vascular trauma

• Vascular trauma means an artery or vein has been torn, cut, punctured or thrombosed by blunt, penetrating or iatrogenic force. It can exsanguinate a patient or ischaemise a limb.
• Examine first for hard signs of vascular injury: active bleeding, an expanding haematoma, absent or diminished pulse, a thrill or bruit. These mean operate now.
• If there are no hard signs, measure an ankle-brachial index after re-alignment. An index below 0.9 needs imaging; above 0.9 with a normal examination is compatible with safe discharge.
• CT angiography is the first-line imaging study when imaging is needed and the patient is stable.
• Temporary adjuncts matter: tourniquets for uncontrolled bleeding, temporary intravascular shunts for damage control or orthopaedic stabilisation, and timely repair before 6 hours of limb ischaemia when feasible.
• The two killers to anticipate at the end of repair are reperfusion injury and compartment syndrome. Measure compartment pressure and fasciotomise when it is above 30 to 35 mmHg.

By the end of this page you should be able to:

1. List the hard and soft signs of vascular injury and say what each implies.
2. Explain how an ankle-brachial index is measured and when it changes management.
3. Choose and interpret first-line imaging for a stable patient.
4. Describe the roles of tourniquets and temporary intravascular shunts.
5. Plan definitive repair and say when a popliteal injury mandates fasciotomy.
6. Recognise and treat reperfusion injury and compartment syndrome.
7. Place these decisions in the context of current AAST–WSES, EAST and ESVS guidance.

• Transection or partial transection produces haemorrhage, often with an expanding haematoma or active bleeding.
• Intimal tear or flap may cause thrombosis and delayed occlusion while the external vessel looks intact.
• Contusion and vasospasm can produce delayed ischaemia without obvious bleeding.
• Pseudoaneurysm and arteriovenous fistula are delayed consequences rather than immediate ones, and may present days to weeks later.

Peripheral injuries of the extremities are among the most commonly injured vessels in both civilian and military trauma, and open surgical repair remains the first-line therapy in most patients.^[1] Vascular trauma also includes injuries to vessels in the neck (carotid, vertebral, jugular), thoracic aorta and great vessels, abdomen, and pelvis, each with its own exposures and control problems. The ESVS vascular trauma guideline covers all of these territories with 105 recommendations, so the diaphragmatic boundary is not the aorta alone; the principles of control, imaging and reperfusion apply throughout.^[4]

Blunt mechanisms are more frequent than penetrating ones in most civilian settings except during conflict or in certain geographic areas, whereas penetrating trauma still dominates peripheral arterial injury in many trauma centres.^[1] Combined arterial and venous injuries, and injuries in proximity to fracture (for example a popliteal artery injury with a tibial fracture), are the high-risk patterns because they combine bleeding, ischaemia and swelling.

1. Local vessel injury. The wall is damaged, bleeding occurs, and thrombus or an intimal flap may occlude the lumen.
2. Loss of distal perfusion. Tissue downstream becomes ischaemic. Muscle tolerates warm ischaemia poorly; nerve dysfunction appears early as paraesthesia, then pain, then paralysis.
3. Swelling. Ischaemia plus venous injury, muscle damage and extravasated fluid raise tissue pressure, and when pressure exceeds perfusion pressure a compartment syndrome develops.
4. Reperfusion injury. When flow is restored after significant ischaemia, oxygen-derived free radicals, calcium overload and the inflammatory response can injure endothelium, muscle and nerves that were still viable a few minutes earlier.

Physical examination and simple bedside measurement of pulse pressures are the key early tools, and hard signs should take the patient straight to theatre without waiting for imaging.^[1][2]

The incidence of any arterial injury in patients with soft signs ranges from about 3% to 25%, depending on which signs are present, so a normal first examination does not exclude an injury, but the absence of hard signs is excellent evidence against a clinically significant arterial injury.^[2] About 1% to 4% of patients with normal examination findings have a delayed presentation of an undetected injury, which is why compulsive follow-up matters.^[2]

The ankle-brachial index (ABI) is the bedside ratio of the systolic blood pressure in the injured extremity distal to the area of injury over the systolic blood pressure in the brachial artery of the uninjured upper extremity. A Doppler device is used if a pulse is not palpable by hand.^[2]

• An ABI below 0.9 should be combined with an abnormal physical examination and taken as an indication for imaging to rule out vascular injury.^[2]
• An ABI above 0.9 with a normal physical examination is compatible with safe discharge home in the absence of other injuries requiring admission, with clear follow-up instructions.^[2]
• In 90 patients prospectively screened using this approach and discharged with an ABI above 0.9, the overall complication rate was 5.5%, and most complications were soft tissue infections; bleeding, limb loss and ischaemia did not develop in any patient.^[2]
• In older patients with pre-existing peripheral arterial disease the ABI is less reliable. Some centres therefore use a difference of at least 0.1 between the injured and uninjured extremities as an additional indication for imaging.^[2]

CT angiography, using intravenous contrast and multidetector CT, is the imaging study of choice when a stable patient with suspected arterial injury needs imaging. In prospective and retrospective studies of lower extremity penetrating trauma its sensitivity and specificity for clinically significant arterial injury are reported at 100%, and it saves time and cost compared with conventional arteriography.^[2] Levels of evidence in current vascular surgery guidance place CT angiography as the primary diagnostic study when imaging is required for penetrating lower extremity vascular injury.^[2]

Practical points:

• It is readily available, uses intravenous rather than intra-arterial contrast, and is often performed with other trauma CT studies.
• Its limitations include scatter artefact from metallic fragments, difficulty with small tibial or forearm vessels, and the fact that it cannot be therapeutic.
• The injured extremity should be re-aligned or reduced before imaging so that anatomical relation is restored; an occluded artery may reperfuse after reduction of a dislocation.
• Duplex ultrasound may be a useful adjunct in skilled hands for soft signs or proximity injuries, but its role in these patients is not well defined.^[2]

The first approach to bleeding from a vascular injury is direct manual pressure or a pressure dressing. Where direct pressure fails, a tourniquet is a temporary adjunct until definitive repair. Recent military and trauma experience shows that tourniquets, when applied correctly, can be life saving, with low complication rates when ischaemic time is kept as short as possible.^[2] Apply the tourniquet proximal to the bleeding point at the level likely to control both arterial and venous inflow, note the time of application on the casualty, and remove it once definitive care is available.^[2]

Balloon tamponade (for example a Foley catheter in a deep tract) and junctional haemorrhage devices are sometimes used when a tourniquet cannot be placed (neck, groin, axilla); these are local techniques and their use should follow local protocols.

A temporary intravascular shunt (TIVS) is a short tube placed in the injured artery or vein to restore perfusion or drainage while definitive repair is deferred. Its two situations are:

• damage control when the patient's physiology prevents immediate definitive repair;
• combined vascular and orthopaedic injury, where perfusion must be maintained during fracture stabilisation and repair.^[2]

Current evidence supports using the largest available shunt and not using routine anticoagulation, because patients are usually coagulopathic and patency rates are high.^[2]

Open surgical repair remains the first-line therapy in most patients with vascular trauma.^[1] Principles are the same whether the injury is in the neck, thorax, abdomen, pelvis or extremity: obtain proximal and distal control before exploring the haematoma, debride the injured wall, then repair without tension.

Options, chosen by size of defect and contamination:

1. Lateral sutures or vein patch angioplasty for a small clean defect.
2. End-to-end anastomosis when the ends can be brought together without tension.
3. Reverse autologous vein graft (usually reversed great saphenous vein) for gaps too long for primary anastomosis.
4. Synthetic graft (for example PTFE) in contaminated fields or when vein is unavailable; PTFE is acceptable in a contaminated wound, although soft tissue coverage should be sought.^[2]
5. Ligation of a dispensable vessel if repair is unsafe (for example single-vessel tibial or small branch) or if the patient's physiology precludes repair. Tibial vessels may be ligated if distal flow is documented.^[2] Iliac and large named arteries should be repaired or shunted rather than ligated in the hypotensive patient because ligation causes limb ischaemia.
6. Embolisation of branch bleeding (profunda femoris, tibial branches, internal iliac branches) is acceptable when the main axis is preserved.^[2]

A popliteal artery injury deserves special respect: always begin the repair with a fasciotomy, because the popliteal space tolerates compartment swelling poorly and post-operative pressure rises quickly.^[3]

Reperfusion injury is the damage that appears when blood flow is restored to ischaemic tissue that has been without adequate perfusion. It is not the ischaemia itself but the restoration that injures endothelium, muscle and nerves through oxygen-derived free radicals, calcium influx, leucocyte activation and microvascular plugging. A classic setting is a suprarenal aortic cross-clamp in a haemorrhaging patient, followed by restoration of distal flow once stability is regained.^[3]

Clinically this means that the limb or abdomen may worsen in the first hours after technically successful repair. Anticipate it, recheck perfusion and compartment pressure, and avoid calling the case finished when the last stitch is tied.

Compartment syndrome is raised pressure within a closed fascial space high enough to impair perfusion. In vascular trauma it follows prolonged shock, arterial occlusion, combined arteriovenous injury, ligation of an artery or vein, crush injury, massive tissue damage or swelling.^[3]

Suspect it when the limb develops pain at rest or on passive stretch, a tense compartment, paraesthesia, or raised pressure on measurement. Treat it early with a fasciotomy that decompresses all compartments of the affected segment. In the lower leg this means a two-incision four-compartment fasciotomy.^[2][3]

Where the abdomen has been opened under high pressure and significant swelling exists, anticipate intra-abdominal hypertension and abdominal compartment syndrome after release of an aortic clamp, and keep the same proactive approach to measurement and decompression.^[3]

Measure compartment pressure before moving a patient with significant vascular injury out of theatre when there has been cross-clamping or prolonged ischaemia. A pressure above 30 to 35 mmHg is a signal to perform four-compartment fasciotomy.^[3] If fasciotomy is not performed, compartment pressure should be monitored closely, with a low threshold to decompress.^[2]

The major vascular trauma and vascular surgery bodies converge on the same sequence of decisions:

• EAST practice management guideline for penetrating lower extremity arterial trauma: hard signs go to the operating room without imaging; soft signs go on to examination and ABIs; an arterial extremity injury should be reperfused in under 6 hours when possible; CT angiography is the primary imaging study when imaging is needed; tourniquets are temporary adjuncts; temporary shunts restore flow in Gustillo IIIC fractures or damage control situations; early four-compartment fasciotomy is applied liberally with prolonged ischaemia.^[2]
• AAST–WSES guidelines on peripheral vascular injuries state that physical examination and simple bedside investigations of pulse pressures are key to early identification; in stable patients with equivocal examination, CT angiography is the mainstay of screening and diagnosis; immediate open surgical repair remains the first-line therapy in most patients; prevention, early detection and treatment of compartment syndrome remain essential.^[1]
• ESVS clinical practice guidelines on vascular trauma issue 105 recommendations covering care across the neck, thoracic aorta and thoracic outlet, abdomen, upper and lower extremities, with dedicated sections on bleeding control and restoration of perfusion and on post-operative considerations. They place vascular trauma care within one multidisciplinary framework.^[4]
• The WSES position paper on vascular emergency surgery emphasises vascular control before exploring any haematoma, short temporary shunting for physiology, and popliteal repair beginning with fasciotomy. It also reminds that absolute primary amputation indications in lower extremity vascular trauma include more than 6 hours of ischaemia and disruption of the posterior tibial nerve.^[3]

• Damage control operations: ligate, shunt and pack, return later. A temporary shunt in a vessel of a physiologically unstable patient is safer than an exhausted repair.
• Combined vascular and fracture injury: a shunt while orthopaedic stabilisation is performed protects perfusion.
• Low-resource settings: the diagnosis is clinical first. Re-align the limb, feel for pulse, measure an ABI that requires only a Doppler or a blood pressure cuff, and control bleeding by pressure and tourniquet. CT angiography and endovascular therapy are refinements for the stable patient with equivocal findings rather than prerequisites for life- or limb-saving care.
• Follow-up: between 1% and 4% of patients with initially normal examinations present later with undetected injury, so every patient with a potential vascular injury needs instruction and clinic review.^[2]

Blunt carotid and vertebral injury is often silent and is sought after significant blunt neck trauma, seat-belt abrasion, or high-risk mechanisms. CT angiography is the usual screening study in modern trauma systems. Management balances repair, endovascular stenting or antithrombotic therapy against the risk of thrombosis and stroke, and follow-up imaging is needed because lesions can evolve. Penetrating neck injuries with hard signs go to theatre; in the stable patient without hard signs, CT angiography delineates the arterial and venous injuries. Airway control always comes before vascular control if there is expanding haematoma or laryngeal displacement.

Blunt injury to the thoracic aorta (usually at the aortic isthmus) and its branches is high-energy trauma. Diagnosis is by CT angiography, and definitive management in stable patients is increasingly endovascular (TEVAR), with open repair reserved for anatomy or device limitations. Post-repair surveillance imaging is needed for endograft-related complications. Traumatic injuries of the arch vessels and subclavian/axillary vessels combine control problems with brachial plexus and airway considerations.

The abdomen and retroperitoneum hide bleeding in three zones. Contained haematomas from blunt trauma in zones 2 and 3 may be observed or addressed angiographically, while haematomas from penetrating trauma and all zone 1 haematomas usually require exploration. Active haemorrhage demands formal proximal and distal vascular control, correction of gastrointestinal contamination, repair, and (often) damage control before definitive reconstruction. Retroperitoneal vascular injuries are easy to miss on initial laparotomy because bleeding is contained in the retroperitoneum.

Pelvic vascular trauma is often venous and bony in origin. Bleeding is initially controlled by pelvic binder, resuscitation and, where needed, angioembolisation or pre-peritoneal packing. Internal iliac artery injuries and their branches are amenable to embolisation while the main axis is preserved; repair or ligation follows for the common and external iliac axes. Pelvic fracture haemorrhage can consume blood products rapidly and should be anticipated with early massive-transfusion planning.

Veins bleed under low pressure but large ones (inferior vena cava, iliac and femoral) can exsanguinate when the patient is vasoconstricted. Repair by lateral sutures is preferred; ligation of a large vein is a damage control manoeuvre that obliges measurement of compartment pressure and close fluid management in the early post-operative period. Venous injuries often coexist with arterial injuries, and a combined arteriovenous injury is a strong risk factor for compartment syndrome.

The decision between immediate repair, shunt and damage control should be made on the patient, not on the clock alone:

• Repair immediately when the patient is physiologically stable and the injury is anatomically simple.
• Shunt when an orthopaedic or soft tissue repair must precede vascular repair, or when active bleeding must be stopped quickly but a long definitive procedure is unsafe.
• Damage control (temporary control, packing, closure, return for definitive repair later) when the patient is cold, acidotic, coagulopathic or has multiple competing injuries. A shunt placed in a cold, coagulopathic patient with poor runoff may thrombose; ligation of a dispensable vessel is then the better choice.
• After any cross-clamp or prolonged ischaemia, measure compartment pressure and recheck distal pulses before leaving theatre.
• Completion imaging (angiography or duplex) after arterial repair is widely recommended to confirm that no technical defect, intimal flap or distal thrombus remains.

• Early after operation: recheck perfusion and neurology, monitor drainage, and watch for expanding haematoma, compartment syndrome and reperfusion oedema.
• Reperfusion injury: can worsen neuromuscular function after technically good repair; supportive care, elevation, and strict compartment pressure monitoring are the mainstays, with fasciotomy when indicated.
• Infection and dehiscence: especially in contaminated wounds and after synthetic graft placement; soft-tissue coverage should be planned early.
• Delayed pseudoaneurysm and arteriovenous fistula: may present weeks later with a mass, bruit, limb swelling or rupture; duplex ultrasound is the usual first investigation, with CT angiography for planning.
• Amputation level and rehabilitation: for patients who undergo amputation after vascular trauma, early multidisciplinary rehabilitation and prosthetic fitting improve long-term outcomes. Avoid premature amputation in a viable limb; equally, avoid prolonged attempts at salvage when the physiology or soft tissues will not recover, informed by the more than 6 hours of ischaemia and other severe criteria.

Outcome after vascular trauma is driven more by overall injury severity, shock and associated injuries than by the vascular repair alone. Extremity injuries repaired promptly with restoration of flow inside the 6-hour window are associated with the best limb salvage. Popliteal artery injuries, combined arteriovenous injuries, and mangled extremities carry the highest risk of limb loss and of long-term neuropathic pain. Survivors of severe vascular injury may require prolonged physiotherapy, pain management and, in some cases, post-traumatic stress support.

Much vascular trauma is accidental, but some is preventable:

• Restraint use, driver and speed safety measures, and control of penetrating violence reduce the incidence.
• In hospital, careful technique and antithrombotic discipline around invasive lines and procedures prevent iatrogenic injury.
• Early imaging of at-risk patients (for example those with high-mechanism blunt trauma and seat-belt marks) identifies occult intimal injuries before they thrombose or rupture.

• Re-align and splint the injured limb, then look and feel for distal pulses and measure an ABI that requires only a cuff and a Doppler.
• Control bleeding with direct pressure, pressure dressings or tourniquet; note the time of tourniquet application on the patient.
• Avoid unnecessary arteriography where CT angiography is unavailable: the clinical signs and ABI separate the patients who need operation from those who can be observed.
• Repair or shunt the large named arteries; ligate only those whose sacrifice is tolerated.
• Perform a fasciotomy whenever the repair has been preceded by prolonged ischaemia or when the compartment feels tense.
• Refer early when repair exceeds local capability, because reperfusion after a long ischaemic interval is dangerous.
• Send all resected or embolised material and every repaired vessel's histological sample, where possible, and arrange follow-up for delayed pseudoaneurysm.

• Vascular trauma kills by haemorrhage and by limb ischaemia. Control bleeding before chasing the diagnosis.
• Hard signs (active bleeding, expanding haematoma, absent pulse, bruit or thrill) demand operation without imaging.
• Soft signs (non-expanding haematoma, history of bleeding, proximity, neurological deficit) need ABI measurement and either discharge above 0.9 or imaging below 0.9.
• The ankle-brachial index is systolic pressure distal to the injury divided by brachial pressure in the uninjured arm, measured by Doppler when needed.
• CT angiography is the first-line imaging study when a stable patient needs imaging, with reported 100% sensitivity and specificity in prospective and retrospective studies.
• Restore perfusion to an ischaemic limb in under 6 hours whenever feasible. ^[2]
• Tourniquets and temporary intravascular shunts are adjuncts, not definitive treatment.
• Definitive repair should use the simplest repair that will hold; autologous vein graft is preferred for gaps, synthetic grafts (including PTFE) are acceptable in contamination, and ligation is reserved for dispensable vessels.
• Always fasciotomise before starting a popliteal repair.
• Warm ischaemia, cross-clamping and venous ligation demand measurement of compartment pressure; fasciotomise if pressure is above 30 to 35 mmHg.
• Recognise and anticipate reperfusion injury: clinical worsening after a technically good repair means look again.