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Pathophysiology
Missile damage is related to the velocity
Shotgun causes multiple perforations and can cause embolization
Blunt trauma results from shearing or distraction
Vascular spasm occurs at or distal to the injury due to the unapposed sympathetic constriction, it is not the cause for ischaemia
Soft signs
History of a significant bleed Small non expanding haematoma Associated nerve injury Proximity to a major vessel
Unclear presentation
Thorax injuries- suspect if there is a widened mediastinum, persistent shock, large haemothorax
Intimal injury- the pulses maybe intact but the exposed collagen is very thrombogenic
Mediastinum
Fracture of 1st,2nd ribs, sternum and scapula
Sterno clavicular joint dislocation Trans axial gunshot Widened mediastinum Obliteration of aortic notch, left apical
pleural cap, aorto-pulmonary window Left haemothorax Oesophageal and tracheal deviation to the
right Depression of left main bronchus
Limbs
Multiple fractures Multiple penetrating injuries Shotgun Knee/elbow dislocation Degloving injury Gunshot tract along the long axis of
the vessel
Duplex ultrasound
Combines pulsed doppler and real time B mode ultrasound imaging
Advantages- non invasive, cheap, no radiation and sensitive
Locally used for neck zone II and single peripheral injuries
Angiography
Gold standard imaging and there is a therapeutic option, although it is invasive
Features suggestive of injury- extravasation of contrast, dilatation due to intimal injury, narrowing, occlusion, filling defects and AV fistula
CT angiography
Sensitivity and specificity of 90-100% Advantage is that it is non invasive
and rapid Disadvantages – lack of therapeutic
options, artifacts from foreign bodies, streak artifacts simulating intimal tears and the imaging of the arch not good on CT
Management
All vascular injuries should be repaired as ASAP to avoid delayed bleeding, compressive haematoma and limb compromise
We do not believe in conservative management of minimal arterial injuries because the history is unpredictable, poor patient compliance and too late presentation of complications
Mangled extremity severity score
Skeletal/soft tissue injury Limb ischaemia Shock Age
Score of >7 is accurate for predicting eventual need for amputation
Prophylatic fasciotomy
Prolonged hypotension Extensive soft tissue injury Arterial and venous injury Bone plus vascular injury Delayed vascular repair Inability to assess the patient, e.g.
head/spinal injury
Therapeutic fasciotomy
Increased tissue turgor Extensive deep haematoma in the
presence of ischaemia
FASCIOTOMY BEFORE VASCULAR REPAIR
Principles of vascular repair
Digital or sponge pressure and catheter to control bleeding
Prophylatic antibiotics Access available to the groin for the graft Wide exposure with proximal and distal
control Edges debrided to healthy intima Embolectomy and flushing with heparin
saline Vascular repair before ortho Adequate tissue cover of the vascular
repair
Techniques of repair
Lateral – for wide calibre vessels Patch- to prevent stenosis End to end- single tethering stitch
should hold and < 4mm vessel should have interrupted sutures
Interposition graft- NB similar size with the injured vessel
Ligation- gross contamination and unstable patient
Types of grafts
Vein- no cost and low infection rate Arterial- same advantages as the
vein but the donor site may need to be replaced
Synthetic- ? Higher infection risk, expensive and poor patency across joints
Causes of graft thrombosis
In flow
Anastomosis – intimal injury, adventitia, tension, stenosis, poor graft
Run off