Pre-operative assessment

Hard signs of vascular injury:
- Pulsatile bleeding
- Expanding haematoma
- Presence of bruit/thrill
- Evidence of ischaemia (six P's)
Soft signs:
- History of significant haemorrhage
- Injury in proximity to a major vessel
- Non-expanding haematoma
- Diminished or asymmetric pulses
- Unexplained hypotension or tachycardia
Investigation
- CTA is best
- Duplex USS
- Segmental pressures

Minor injuries - majority of these can be followed non-operatively, if asymptomatic in a stable patient.

Non-occlusive intimal flaps
Non-flow-limiting stenoses
Small false aneurysms
AV fistulae

Neck injury

See separate topic - penetrating neck injury
Hybrid endovascular techniques are favoured for zones 1 and 3 due to difficulty of exposure, especially for zone 3 ICA or subclavian artery
ICA:
- Grade 1 to 4 injuries are treated with stroke prophylaxis - anticoagulation vs antiplatelets
- Some grade 3 and progressing grade 2 lesions should be stented, especially if a/w neurological events
- Grade 5 lesions in poorly accessible locations are treated with endovascular stents; otherwise open surgery is indicated
Vertebral artery:
- V1 segment is accessible (origin through to transverse foramen of C6)
- V2 or V3 segments are surgically inaccessible, and should be treated either by endovascular stenting or by ligation in V1
Accidental carotid canulation
- Often a/w through and through IJV injuries that are not amenable to percutaneous closure
- Heparinise patients early
- Closure should be performed in OR or hybrid suite
- Balloon can be placed proximal to injury in case proximal control is needed - can use femoral approach
- Catheter then removed and percutaneous closure device deployed/stent deployed/cut down to artery
- Completion angiogram to rule out any extravasation
- Stent may be required (especially for carotid injuries) if evidence of AVF/pseudoaneurysm

Chest:

Major vascular injury generally requires operation
Ascending/transverse aorta and innominate artery left CCA: median sternotomy
Descending aorta and left subclavian: left anterolateral thoracotomy
Aortic - Blunt trauma can cause aortic isthmus injury, although 80% die at scene. Can see patients with contained injuries (intramural haematoma or false aneurysm) in hospital. Decrease risk of rupture by prompt control of HR and BP. Definitive repair can be deferred up to 24 hours to allow resus and stabilisation, unless they also have a head injury requiring higher BP, in which case it should be repaired immediately.
- Thoracic endovascular aortic repair (TEVAR) is preferred for blunt aortic injury - now recommended whenever anatomically possible. Need to land in healthy aorta with at least 20mm of neck proximal and distal to the aortic injury. This can lead to coverage of left subclavian. Patients with absent right vertebral artery or prior left internal mammary artery cardiac bypass should have early revascularisation. If problems with TEVAR occur, it's usually within the first 3 months.
- Most grade 1 injuries heal spontaneously - serial imaging (around day 3), impulse control
- Grade 2: likely safe to observe. Some people group them with grade 1 injury.
- Grade 3: perhaps feasible to manage non-operatively, but this is dangerous, and needs to carefully considered. Most would repair them, but can be delayed while other injuries are managed and the patient is stabilised.
- Grade 4: proceed immediately for repair
Axillosubclavian:
- Open exposure is difficult and time-consuming
- CTA will be very helpful - even if the patient is unstable - try to get the patient through the scanner
- Endovascular has lower morbidity and mortality when feasible - but is often used in more stable patients with less severe injuries. Brachial access is often the quickest way to get across it (can be percutaneous, but in practice a brachial cutdown is often preferred). Covered self-expanding stents or balloon-expandable stents can be used, and 10-20% oversizing is recommended. Note very high risk for stent thrombosis.
Tracheoinnominate artery fistula
- Caused by pressure of tracheostomy cuff against overlying crossing innominate artery
- Presentation
  - Suspect in any patient with new bleeding from tracheostomy, especially if it was placed >3 days ago
  - Quite commonly has herald bleed followed by catastrophic bleed - needs urgent evaluation
  - Bronchoscopy is diagnostic (look for lesion on anterior trachea wall adjacent to pulsation of artery) - CTA rarely gives answer
- Maneuvers:
  - Ready OT
  - Over-inflate tracheostomy balloon
  - If ineffective, try digital compression of innominate against manubrium (Utley maneuver) after placing a finger into pre-tracheal plane, usually through tracheostomy after orotracheal intubation
  - Reasonable to attempt endovascular repair if facilities available, with close post-op follow-up and lifelong antibiotics (stent-graft placement across the lesion via femoral approach, although carotid approach can also be used)

Abdomen/pelvis

Keep in mind REBOA/thoracotomy for proximal control
Zone-based system is helpful for penetrating trauma (see retroperitoneal haemorrhage section under 'Trauma')
Injuries to aorta, coeliac artery, SMA, or left-sided zone 2 injuries are best explored to medial visceral rotation
SMA - need to repair/bypass/shunt, ligation isn't tolerated
Coeliac - can be ligated
IMA - can be ligated
IVC ligation results in significant morbidity. Use right medial visceral rotation to approach.
Stable patients with localised injuries can often be managed endovascularly.

Limb

Presence of hard signs of vascular injury mandates exploration (except AVF)
Soft signs or AVF should mandate CTA
Hybrid theatre if possible
If the injury results in little or no loss of length, repair primarily in transverse fashion with proline. Patch angioplasty or segmental interposition grafting may be required.
Brachial - explore via medial longitudinal incision positioned in the groove between the biceps and triceps muscle
Isolated radial or ulnar artery injuries can be ligated, but check there is flow in the collateral vessel with USS prior to ligation. If combined radial and ulnar injury, need to repair one of them (mostly the ulnar artery is larger, at least in the proximal forearm).
SFA - expose in a plane in front of the anterior edge of the sartorius muscle. Most injuries require interposition grafting.
SFV - repair if feasible, but can be ligated.
CFV - repair when possible.
If doing major venous ligation, give strong consideration to calf fasciotomy.
Popliteal - need high index of suspicion in hyperextension injury, as pulse examination is often benign. CTA is indicated in traumatic knee dislocation. Bypass grafting is generally required - contralateral vein is generally preferred, but a short interposition graft e.g. PTFE is acceptable. Fasciotomy considered.
Tibial artery - can be sacrificed if remaining vessels are patent. If multiple injured, vein interposition grafting is necessary to the one best supplying the foot.

Principles of open vascular repair:

Consider pre-op angio
Consider pre-emptive fasciotomy
Widely prep, with autologous conduit in mind
Use an incision that can be extended if necessary
Proximal control is KEY - preferably proximal to an anatomic barrier
Distal control is not completely obligatory, and can often be acquired through the haematoma
Explore the vessel by working in the peri-adventitial plane - look for pearly-white arterial wall with vaso-vasorum on it
Define injury early:
- Which vessels are involved?
- How bad is it? Laceration, transection, or both?
- Where are you? Are there other structures or major vessels nearby?
Decide between complex vascular repair and damage control
- Overall patient condition
- Your skills and the environment
Damage control
- Ligation
  - External carotid artery
  - Coeliac axis
  - Internal iliac
  - Most large veins can be ligated with impunity - vein repair is a luxury, not a must
  - Avoid ligating portal vein where possible
- Temporary shunts
  - Use whatever is available
  - Failure is due to:
    - Failed inflow (proximal injury and residual clot)
    - Obstructed outflow (residual clot or migration or shunt)
    - Obstructed shunt (ligation too tight or kinked)
    - Shunt dislodgement (rapidly expanding haematoma)
- Definitive repair
  - End-to-end anastomosis
    - Often very hard to get enough length and you end up doing interposition graft regardless
  - Patch angioplasty
  - Interposition graft
    - Best option in a completely transected artery