Penetrating Neck Injury

Overview
Posterior triangle injuries
- only require operative management for bleeding control and wound repairs.
Anterior triangle injuries require careful operative consideration.

Airway
Life threatening injuries are caused by cartilage / trachea rupture, soft-tissue airway compression or active hemorrhage into the tracheobroncial tree due to fistula.
Emergency operation.
Signs of airway injury:
- air escape through skin
- dyspnea, stridor, hoarseness
- subcutaneous emphysema
Patient may lean forward with haemoptysis - let them; do not lie down until ready for rapid sequence.
Cricothyroidotomy usually not needed, but may be if access fails.
Significant hemoptysis portends arterial tracheal fistula.  Inflate ETT. Explore.

External Bleeding
Hard signs of bleeding are expanding / pulsatile haematoma, external haemorrhage, distal ischaemia, perhaps bruit / thrill.
Apply direct pressure with a gloved finger until prepped in OR.
Emergency operation

Urgent operation?
When large hematoma, pulsatile hematoma, continued oozing, cervical crepitus, hoarseness, dyspnea and large wounds with soft tissues severed.

Urgent diagnostic investigations?
Patients without above features will need diagnostic investigations.
These pts may have some bleeding that ceased, hoarseness, bruit, dysphagia, mild neck swelling.
Examine neck and oral cavity, chest and do a CXR.
Combined endoscopy of trachea and esophagus recommended if suspected injury.
Barium swallow is not recommended as is hazardous and fails to identify some injuries.
CT angiogram or color-flow duplex for arterial injuries.

Observe or Explore?
If no hard signs, depends on zone of anterior triangle affected.
Zone 1 = thoracic outlet. From clavicle to cricoid.
- explore if confirmed injury to vessels, trachea or esophagus.
Zone 2 = cricoid to angle of mandible.
- formerly all mandated exploration. now only if evidence of organ injury, hematoma, continued bleeding or suspicion tracheal / oesophageal injury.
Zone 3 = mandible to base of skull.
- explore if angiographic evidence of arterial injury.
 
Exposure
Usually ipsilateral incision along SCM.
Extend through platysma into deeper planes.
Retract trachea and thyrid anteriorly.Neurovascular bundle and esophagus posteriorly.
This exposes the tracheoesophageal groove, can then decide which direction to proceed.
Identify and ligate superficial crossing veins along with omohyoid.
Special points
Could detach mandible posterior to angle and subluxate anteriorly to repair a high zone 3 internal carotid injury.
Zone 1 structures can require a median sternotomy to explsore trachea, innominate artery, L common carotid, subclavian a + v, innominate vein and SVC.
Retraction of the medial head of the clavical facilitates exposure, control and repair of the subclavians.

Specific Injuries

Venous
Small veins like EJV are best ligated.
Internal jugular can be repaired using a running nonabsorbable fine suture like prolene.
Large through and through wounds of IJV = ligate the vein; well tolerated by trauma pts.

Arterial
With proximal control, dissect just above the clavicle and proceed distally.
Digital pressure on the bleeder while getting distal control.
Primary laterial repair using 5-0 prolene.
May need resection for gunshots; if <1cm defect primary anastomosis, else reverse saphenous graft interposition; avoid prosthetics unless no saphenous.
Local heparin proximal and distal witout total body heparinization.
Temporary arterial shunt if bleeding cannot be controlled within 30 minutes.

For zone 2 injuries, branches of external carotid can be safely ligated.
If bifurcation involved, intact external carotid can be anastomosed to internal distal to area of damage
If neurological defecit, probably proceed to repair of carotid anyway; unlikely to convert ischaemic to haemorrhagic stroke.

Esophagus
Free esophagues from trachea anterioraly and prevertebral fascia posteriorly and sling with a penrose.
NG facilitates this.
Repair unilateral stab wounds in two layers:
- incorporate full thickness mucosal and muscular wall in inverted inner layer with absorbable suture.
- second layer with interrupted 4-0 permanent sutures.
If bilateral injury, rotate esophagus to repair other side. Do not miss penetrating injury or esophageal cutaneous fistula results.
Leave a drain beside the esophagus; monitor for amylase as suggestive of leak. Leave NG for feeding post op.
Early operative intervention means low risk of leak.
If fistula develops, NG feed over 3 weeks. 

Pharynx
Blood seen on deep oral exam.
Primary closure with full-thickness inverted bites of tissue using absorbable suture --> hemostasis and closure.

Trachea / Cartilage
Free trachea off tracheo-esophageal groove.
Posterior wall perforations can be repaired with running or interrupted 3-0 absorbable sutures with knots tied outside.
Anterior wall requires sutures around tracheal rings.
Heavy sutures tat can go through cartilage for cartilagenous injuries.
May need tracheostomy.

Thyroid
Haemostasis with simple sutures of diathermy.
May need to resect if injury goes through thyroid into trachea; or to better access trachea for repair.

RLN
Rare problem. Best left alone if gunshot to area.
If definitely severed, can try primary repair with a fine suture. Outcome unknown.

Thoracic Duct
Lymph in operative fied.
Free duct, isolate, dived and ligate each end carefully.

Neck Trauma

 

· defines as violation of platysma muscle.

If a penetrating neck wound does not violate platysma then the patient can be discharged from ED.

· transcervical gunshot is associated with a high rate of vital organ damage (70%) - only 20% need a therapeutic operation however

· other penetrating trauma carries a 10-15% risk of needing a therapeutic operation

 

Management priority

· Airway control maintaining cervical immobilization.

· Early intubation without use of muscle relaxant

· Fibreoptic intubation using LA

· Cricothyroidotomy if intubation is not possible

· Haemorrahge control with digital pressure or foley catheter through wound

What are the important symptoms in neck trauma

· Airway and breathing compromise –

                        Hoarse voice

                        Stridor

                        Dyspnoea

                        Haemoptysis

                        Subcutaneous emphysema

only 1/3 patients with emphysema have injury to larynx, pharynx or esophagus

· Expanding haematoma, pulsitile neck mass

· Dysphagia or haematemesis

· Neurological deficit: Horner’s syndrome

Blunt

· ­ frequency

· Laryngeal trauma due to direct injury. Symptoms include:

— Pain

— Tenderness

— Anxiety

— Posture

— Horseness

— Emphysems

— Soft voice

· oesophageal trauma associated with damage to other organs

— trachea

— gt vessels

— Cx spine

· Can also cause rupture of thoracic oesophagus or OGJ

Penetrating

Penetrating injury more common on left as most assailants are right-handed

Zones, stability and symptoms

When assessing the patient the management algorithm depends on whether they are           unstable (hypotensive with haemorrhage)

            symptomatic (as defined above) but stable

            asymptomatic

            zone of injury

· Zone 1 sternum notch ® cricoid

· Zone 2 Cricoid ® angle of mandible

· Zone 3 Superior to angle of mandible

· For the haemodynamically unstable patient with uncontrolled haemorrhgae: operative exploration irrespective of zone of injury.


Mx

· Zones 1 injuries

— if stable whether symptomatic or not assess with CT neck (with arterial phase contrast – CTA) and chest and endoscopy (esophagoscopy, bronchoscopy and laryngoscopy) and esophagography using water soluble contrast. When used alone esophagoscopy or esophagography will detect 60% of injuries whilst used together they will detect 90%. These studies are used to find occult esophageal injuries and guide operative approach (thoracotomy may be required).

— Unstable: Explore. For right side a median sternotomy is often required. For left sided injuries a left antero-lateral thoracotomy.

· Zone 2 injuries

—   Symptomatic: Operative exploration.

— Asymptomatic: Universal mandatory exploration of asymptomatic patients produces a high number of negative explorations. These patients may be safely observed as inpatients for 12-24 hours. Transcervical GSW requires CT examination even if asymptomatic.

· »20% of penetrating neck trauma will show vascular injury on angiography

· »10% will have vascular injury requiring repair

· physical examination picks up virtually all of the injuries requiring intervention

· routine studies pick up more injuries but not more that require intervention

· Zone 3 injuries

—   Asymptomatic: observation as inpatient

—   Symptomatic: Angiogram showing both internal and external carotid arteries on both sides. This allows for angio-embolization or stenting of any injuries which are difficult to expose surgically in this zone.

 

 

Emergency care

· 10% of penetrating neck trauma is associated with airway compromise

· 1 attempt at intubation

— without muscle relaxant

— fibre optic if available

— cricothyroidotomy if unsuccessful

· control external bleeding with pressure

· consider foley catheter tamponade if simple pressure is unsuccessful (can put one through the wound into the chest and pull back to compress bleeding subclavian vessels)

· cardiac arrrest with penetrating trauma mandates emergency room thoracotomy

— control bleeding

— x-clamp the aorta

— aspirate r atrium for air

 

Rx

Access

GA. Supine. Arms tucked. Towel between shoulders. Head ring. Head turned to opposite side if C-spine cleared.  Prep chest and neck.

—Trail of safety

· Neck incision along border SCM: curve incision posteriorly 3cm below the angle of mandible to avoid mandibular and cervical branch of facial nerves. Skin. Platsyma. Expose anterior border of SCM.

—   Insert self-retaining retractor.

— SCM retracted laterally

— Omohyoid retracted / divided

· Ligate the common facial veins of the IJ

         · The common facial vein is marker for carotid bifurcation

· Mobilisation of carotid sheath

— Ansa cervicalis can be sacrificed

            Seek and protect (9,10,11,12 cranial nerves)

                        the hypoglossal

                        glossopharyngeal

                        spinal accessory nerves

                        vagus.

— Gain proximal then distal control of carotid in virgin territory before entering a haematoma:

—   Proximal: isolate the CCA using a vascular sling

—   Distal: Haematoma may extend to angle of jaw. Can enter haematoma and insert a Fogarty into the vessels (ICA and ECA) for control.

· Venous injury initially controlled with compression above & below

· Oesophagus – insert a large bore NG or boogee.

—   Approach the esophagus by retracting the carotid sheath laterally and enter the plane between it and trachea. Middle thyroid veins and Inferior thyroid artery will be encountered. The RLN may be difficult to identify.

—   Esophagus can also be approached by passing lateral to carotid sheath, retracting the sheath medially and entering the plane between it and the spine. The exposure is limited but the scope for injury of RLN is less.

—   Fill the field with water and ask for air to be blown into NG tube to see bubbles.

— Mobilised from trachea

— Dissect directly on oesophagus to preserve RLN’s

· If vascular & oesophageal / tracheal injury

— Repair vascular

— Repair oesophagus / trachea

— Interpose strap muscle between to ¯ chance of oesophagovascular fistula

 

Specific injuries

Carotid

· 20% of vascular injuries in penetrating neck trauma

· 6% of penetrating neck injuries

· expose with standard SCM incision

· consider diarticulation of the jaw +/- vertical osteotomy for base of skull lesions – these are difficult and a strong retractor under the jaw and divide the posterior belly digastric

· direct repair – a clean injury (stab) may be amenable to direct suture or repair with interposition graft (synthetic or vein) or patch.

—Give heparin 5000U if feasible

—Open the artery remove thrombus with fogarty

Ligation can be used:

o Ligating the common carotid is less likely to lead to stroke as back bleeding via ICA

o Some surgeons ligate the ICA only if the patient already has a profound neurological deficit >4 hours.

o If there is no backflow of the distal ICA

· interposition saphenous vein graft

· transposition for IC injuries (onto External carotid stump)

· if no neurological deficit and the injury is very high then ligation may need to be done; otherwise repair

· in the absence of neurological deficit repair should be undertaken if at all possible

· use a shunt while undertaking repair for all but the most minor injuries

· repair of ‘minor’ injuries is controversial

— intramural bleeding and obstructing intimal defects probably do need repair

· asymptomatic traumatic occlusion may result in late complications

—   high occlusion may be more risky to repair than to leave

If there is uncontrollable back-bleeding from an inaccessible ICA stump then insert a fogarty, put two clips and cut it for damage control.

 

Subclavian Vessels

· 4% of penetrating neck trauma

· 15% MR in hospital

· MR from venous injury much higher than from arterial injury

· Folley balloon tamponade technique

· varying surgical approaches

— supraclavicular curving incision over clavicle, then downward over deltopectoral groove, subperiosteal excision of medial clavicle

— median sternotomy for proximal injury

— L Anterolateral thoracotomy for injury on the L

· repair arteries with end to end anastamosis; may require an interposition graft (ususally synthetic)

· ligate only in the critical situation

Vertebral arteries

· rarely any neurological problem

· angiography and embolisation

· for severe bleeding complex approach medial to carotid sheath; sweeping longus coli off the bone; opening the vertebral foramen and ligating the vessel

· Arrest intra-operative bleeding with bone wax and try angio/embolization later

Parotid

· injuries to the parenchyma can be repaired with an absorbable suture

· sialoceles or fistulas usually respond to aspiration and compression

· persistant fistulas are an internal fistula can be formed over a no 6 feeding tube through the mucosa of the mouth and secured with suture. Saliva usually stops draining after 7 days and the tube can be removed 3 days later

Laryngotracheal

· 85% confined to the neck

· laryngoscopy, bronchoscopy and oesophagoscopy are mandatory for the stable patient with a suspected injury

— air bubbling through the wound

— dyspnoea

— stridor

— haemoptysis

— subcutaneous emphysema

· surgical approach is through a longitudinal or transverse neck incision. Thoracotomy is very seldom required

· small tracheal wounds with good apposition of edges can be observed – advance the ET tube cuff beyond the injury to eliminate the air leak

Can insert a tracheostomy tube through hole as a damage control measure.

· simple repair is all that is required in most cases (absorbable suture)

· tracheostomy is only indicated for extensive injuries - delayed reconstruction may be required in the unstable patient - usually defects of 3cm can be primarily closed

· undisplaced fractures of the larynx can be managed non-operatively

· most of the rest can be repaired primarily

Oesophageal

· uncommon

· often missed

· pain on swallowing, haematemesis and subcutaneous emphysem are predictive of this injury

· contrast swallow and endoscopy for diagnosis

· if diagnosed early primary repair in one or two layers is indicated

· Damage control option is to put a closed suction drain adjacent to the wound, and close esophagus with a purse string around injury to produce a controlled esophageal fistula

· delayed injuries may not be possible to close primarily

— closure over a T-tube (24 Fr)

— exclusion procedures

Thoracic duct

· fistula though a wound with high fat content

· conservative treatment with TPN or low fat diet usually heals it

· open ligation of the duct and other fancy manoeuvers can be done if it persists for >2 weeks