Introduction
Vascular Trauma
Basics
Vascular injury has two main consequences haemorrhage and ischaemia. Or, in the words of
an anonymous Czech surgeon, "Bloody vascular Introduction
trauma - it's either bleeding too much or it's not Pathophysiology
Diagnosis
bleeding enough".
Management
References
Unrecognised and uncontrolled haemorrhage can rapidly lead to the demise of
the trauma patient. Unrecognised and untreated ischaemia can lead to limb loss,
stroke, bowel necrosis and multiple organ failure. The aim of this article is to
highlight the fundamentals of vascular trauma and provide an approach to the
diagnosis and management of vascular injury.
Arterial and venous structures are most commonly injured by penetrating
trauma, with a much higher incidence in gunshot wounds than for stab injury.
Blunt trauma also carries a significant vascular injury rate, and iatrogenic
vascular injuries are increasing with radiological and minimal access procedures
becoming more commonplace.
Pathophysiology
Haemorrhage is the prime consequence of
vascular injury. Bleeding may be obvious, with
visible arterial haemorrhage, or it may be
concealed. Classically, concealed arterial
haemorrhage may be in the chest, abdomen
and pelvis. Haemorrhage may also be concealed
in the soft tissues of the buttock and thigh, and
blood from facial fractures may be swallowed
and remain unnoticed.
Vascular Trauma
Basics
Introduction
Pathophysiology
Diagnosis
Management
References
Ischaemia results from an acute interruption of flow of blood to a limb or organ.
Oxygen supply is inadequate to meet demand and anaerobic metabolism takes
over, producing lactic acidosis and activating cellular and humoural inflammatory
pathways. If the arterial supply is not re-established in time, cell death occurs.
Skeletal muscle can be rendered ischaemic for 3-6 hours and still recover
function. Peripheral nerves are more sensitive to ischaemia, and prolonged
neurological deficit may result from relatively short periods of tissue ischaemia.
If arterial supply is restored to ischaemia tissue, the sudden release of
inflammatory mediators, lactic acid, potassium and other intracellular material
into the circulation can cause profound myocardial depression, generalised
vasodilatation and initiate a systemic inflammatory response.
Patterns of Vascular Injury
Laceration, with either complete or incomplete transection of the vessel, is the
most common form of vascular injury. Haemorrhage tends to be more severe in
partially transected vessels, as complete transection results in retraction and
vasoconstriction of the vessel, limiting or even arresting arterial haemorrhage.
Gunshot internal iliac artery.
Blunt trauma injures vessels by crushing, distraction or shearing. This results in
contusion to the vessel, which may extend for some distance along its length. An
intimal flap may be formed which will lead to thrombosis or dissection and
subsequent rupture. Thrombosis may propagate for some distance down the
vessel, or embolise to produce more distal effects.
Arterial haemorrhage may continue within a contained haematoma, leading to a
pulsatile mass of clot - a pseudoaneurysm. Commonly, distal flow is preserved
with false aneurysm formation, and diagnosis may be difficult. These are at risk
of rupture if undiagnosed - and often present late after the initial injury is
forgotten.
Pseudoaneurysm, tibioperoneal trunk.
If there is an injury to an adjacent vein as well as to the artery, an arterio-venous
fistula may form, which may subsequently lead to rupture or cardiovascular
compromise. Arteriovenous fistulae also commonly present some time after the
initial injury.
Spasm as a unique entity is never the result of trauma, and should not be
assumed to be the cause of limb ischaemia. Spasm is spelled C-L-O-T!
Diagnosis
The diagnosis of significant vascular injury rests
almost entirely in the physical examination. An
absence of hard signs of vascular injury virtually
excludes the presence of vascular trauma. In
contrast, the presence of hard signs mandates
immediate action.
Vascular Trauma
Basics
Introduction
Pathophysiology
Diagnosis
Management
References
Hard signs of Vascular Injury






Pulsatile bleeding
Expanding haematoma
Absent distal pulses
Cold, pale limb
Palpable thrill
Audible bruit
The presence of hard signs of vascular injury mandates immediate operative
intervention. Usually the site of injury is obvious, and angiography is
unnecessary. If in doubt, angiography can be performed emergently on the
operating room table. Unnecessary interventions and investigations should be
avoided to minimise the delay to definitive care.
So-called 'soft signs' of vascular injury are peripheral nerve deficit, history of
moderate haemorrhage at scene, a reduced but palpable pulse or an injury in
proximity to a major artery. Investigation or exploration of patients with soft
signs alone is not warranted. Patients should be admitted and observed for 24
hours. Development of hard signs is rare, but mandates treatment as above.
High-velocity weapons, multiple fragment injuries and blunt trauma can make
diagnosis less obvious, and angiography can be used to locate, or exclude, an
injury.
Diagnostic Adjuncts
Pulse Oximetry
A reduction in oximeter readings from one limb, as compared to another is
suggestive of, but neither confirms nor excludes a significant vascular injury. It is
thereful essentially an unhelpful test.
Doppler Ultrasound
The diagnosis of a significant (ie. requiring intervention) vascular injury has been
shown to be related to the presence or absence of a palpable pulse. The presence
of a doppler signal in a pulseless limb only gives a false sense of security and
does not imply a less severe or less urgent injury pattern.
A diminished, but palpable pulse is a soft sign of vascular injury. Similarly, a
reduction in the anle-brachial pressure index (ABPI) in the presence of a palpable
pulse does not indicate the presence of a vascular injury requiring intervention.
Doppler ultrasound is therefore adds little to careful clinical examination.
Duplex Ultrasound
Duplex imaging is a non-invasive examination combining B-mode and Doppler
ultrasound. It requires an experienced operator and is more operator-dependent.
Duplex can detect intimal tears, thrombosis, false aneurysms and arteriovenous
fistulae. Its place in the assessment of vascular injury is as yet not completely
definded, but it has a high sensitivity and may be appropriate for use as a
screening tool.
Angiography
Angiography remains the gold-standard investigation for the further investigation
and delineation of vascular injury. In most traumatic injury settings, angiography
is best performed in the operating room, with the surgeon exposing the vessel
proximal to the injury for control and expediency. Transfer to the radiology suite
should be restricted to haemodynamically stable patients eith proximal or torso
injuries. Angiography may be used to treat certain selected injuries, and where
expertise and technical facilities are available. Proximal control may be possible
with an angioplasty catheter prior to transfer to the operating room.