Penetrating neck injuries can involve important structures and require careful assessment and management. The document outlines:
1) A classification system for penetrating neck injuries based on location and depth. Zone I injuries below the cricoid cartilage pose the highest risk to major blood vessels.
2) A primary survey approach following ATLS guidelines is recommended to assess the airway, breathing, circulation, disability and environment. Hard signs of injury to airways or blood vessels require prompt surgical management.
3) Investigation may involve imaging like CT, Doppler ultrasound or angiography to identify injuries requiring surgery versus conservative management for stable patients with no signs of major injury. Early identification of injuries allows for proper treatment to prevent complications.
2. Introduction
Penetrating neck injuries are commonly
seen in South Africa. Although many are
minor injuries of no significance, they may
be deceptive in appearance.
This presentation focuses on a logical
approach to the accurate assessment and
management of penetrating injuries to the
neck, excluding non-penetrating neck
injuries and injuries to the cervical spine.
3. Epidemiologic Features
Firearms are responsible for approximately
44%, stab wounds for approximately 40%,
shotguns for approximately 4%, and other
weapons for approximately 12% of all
penetrating neck injuries in urban trauma
centers in the United States.
Gunshot wounds are significantly more likely
to be associated with large neck hematomas,
hypotension on admission, and vascular or
aerodigestive injuries than knife wounds.
4. Mechanism of penetrating neck
injuries
This type of injury may be the result of
interpersonal violence, for example, stab
or gunshot wounds, or accidents due to
foreign bodies, or iatrogenic incidents
during endoscopy or surgery.
5. Classification of penetrating neck
injuries
A penetrating neck injury is one that has
penetrated platysma.
Probing of the wound with a finger or an
instrument to determine the depth of the
wound is absolutely
contraindicated.
6. Classification of penetrating neck injuries
(cont)
Injuries penetrating the platysma should be
classified as :
Posterior triangle (behind the posterior
border of the sternocleidomastoid muscle)
Anterior triangle (in front of the anterior
border of the sternocleidomastoid muscle)
The anterior triangle is subdivided into Zone
I, Zone II, and Zone III. Zone I is below
a horizontal line at the level of the cricoid
cartilage, Zone III is above the angle of the
mandible, and Zone II lies in between.
11. Posterior triangle
Generally these injuries are less likely to
involve the major structures.
The spinal cord, brachial plexus, and
vertebral arteries may be at risk.
If the injury is very low, the subclavian
vessels or the lung apex could be
involved.
12. Anterior triangle
Zone I
Blood vessels : aortic arch, subclavian, and
innominate (brachiocephalic) vessels
Nerves : brachial plexus, left recurrent
laryngeal nerve, spinal cord, sympathetic
trunks
Respiratory : trachea, apex of the lung
Digestive : oesophagus
Lymphatic : thoracic duct on the left
Thyroid gland.
16. Presentation
Clinical signs of significant injury
Dysphagia – Tracheal and/or esophageal
injury
Hoarseness – Tracheal and/or esophageal
injury (especially recurrent laryngeal
nerve)
Oronasopharyngeal bleeding – Vascular,
tracheal, or esophageal injury
Neurologic deficit – Vascular and/or spinal
cord injury
Hypotension – Nonspecific; may be related
to the neck injury or may indicate trauma
elsewhere
17. Presentation (cont)
hard signs of airway injury
respiratory distress,
Air bubbling through the neck wound,
major hemoptysis
soft signs of airway injury
subcutaneous emphysema
hoarseness
minor hemoptysis.
18. Presentation (cont)
hard signs that strongly indicate vascular injury
severe active bleeding,
large expanding hematoma,
Absent or diminished peripheral pulse,
bruit on auscultation
Unexplained hypotension
Ischemia of distal part (cerebral ischemia)
Soft signs of vascular injury
stable, small to moderate size hematomas,
minor bleeding,
mild hypotension responding well to fluid resuscitation
proximity wounds
19. Presentation (cont)
There are no hard signs diagnostic of
pharyngoesophageal injuries.
Soft signs that require evaluation of the
pharynx and esophagus include
painful swallowing
subcutaneous emphysema
hematemesis.
20. Primary survey
The assessment and management of neck injuries
must follow the ATLS primary survery principles
Airway
Airway compromise may be directly due to injury
or blood; or secondary, e.g. oedema associated
with a haematoma, or vocal cord paralysis
secondary to injury to the recurrent laryngeal
nerve.
If the airway is compromised, oral intubation
should be attempted whenever possible but
facilities to perform an emergency surgical airway
procedure must be present.
If there is an obvious open injury to the airway, it
is better to consider tracheostomy as soon as
possible.
Routine C-spine immolization is not recommended.
21. Primary survey (cont)
Breathing
The apex of the lung may be involved when a neck wound is
present.
Always do a chest X-Ray to check for a haemo- or
pneumothorax.
Circulation
Vascular injuries may present as neurological complications,
e.g. neurological fallout in the distribution of the middle
cerebral artery may be secondary to a carotid artery injury.
A high-flow intravenous line should be set up. Intravenous
lines should be avoided in the arm on the side of the neck
wound.
Active external bleeding can be controlled by external digital
pressure or by inflating the bulb of a Foley’s catheter that has
been carefully inserted as deep as possible into the wound.
This is an emergency measure that provides temporary
control until surgery can be done.
22. Balloon tamponade for bleeding control from the subclavian vessels. It
can also be used for bleeding control from other zones in the neck.
23. Primary survey (cont)
Disability
Neurological deficit may be secondary to
vascular injury; cranial nerve or spinal
cord damage.
Exposure/ environment
Look for other injuries – consider injury
patterns associated with the mechanism of
injury, or the trajectory.
24. Secondary Survey
History
Establish the mechanism of injury, note voice change, ask about
chest pain, dysphagia, haemoptysis, weakness, paresthaesia, or
numbness in the arms.
Examination
Assess for the presence of :
Local bleeding, pulsation, bruit, absent pulses, expanding
haematoma
Air in soft tissues, distended neck veins
Fluid leaking from the wound (saliva, CSF, lymph)
Cranial nerve deficit, particularly CN VII-XII, Horner’s syndrome
Loss of sensation and power in the upper limbs
Loss of sensation and power in the lower limbs
Pneumo-/ haemothorax, abnormal breathing pattern (e.g.
diaphragmatic breathing)
Blood pressure difference of more than 10 mmHg in the 2 arms
Frequent reassessment of the airway is mandatory to check for
impending obstruction due to oedema
25. Investigative management
The mechanism of injury and clinical
examination should determine the need
and type of specific investigations in the
evaluation of PNI.
Patients with hard signs of major vascular
or laryngotracheal injuries should undergo
an operation without any delay for
definitive investigations.
26. Investigative management (cont)
In the stable patient who has no immediate
indication for surgery, the blood vessels,
respiratory, and digestive systems should be
investigated to rule out injury. This may be done
primarily by surgical exploration, or by utilizing
special investigations which may obviate the need
for surgery.
Zone II injuries are readily exposed and accessed,
and are therefore often surgically explored without
preoperative investigations. The structures in Zone
I or III are more difficult to visualize
intraoperatively and need more preoperative
planning and preparation.
27. Chest and neck radiographs may be helpful in locating foreign bodies.
This patient has retained bullets in zones 1 and 3.
28. Investigative management
(cont)Chest X-ray
This is essential in all patients with neck injuries.
Do not sit patient up; if there is an open wound, it may cause a fatal air
embolism or complicate a cervical spine injury.
Cervical spine X-ray
Look for the presence of fractures, foreign bodies, or air in soft tissues.
CT scan or CT angiography
In the stable patient, a spiral CT scan (if available) with intravenous
contrast will provide information on soft tissue, bony structures, wound
trajectory, and vascular injuries.
Specifically look out for intimal injuries of the carotids.
Oral contrast can be given if required to identify leaks.
Color Flow Doppler (CFD)
Color flow Doppler has been suggested as a reliable alternative to
angiography in the evaluation of PNI.
29. Chest radiograph in a zone 1 penetrating injury shows a widened upper
mediastinum which is suspicious for a thoracic inlet vascular injury.
This patient needs angiographic evaluation.
30. Investigative management (cont)
Angiography
Zone I and Zone III : Consider primary angiography if there is any
indication of a vascular injury, such as a blood pressure difference of more
than 10 mmHg in either arm, widened mediastinum on chest X-ray, bruit,
or haematomas.
Angiography may be done after CT if non-surgical management of vascular
injuries (stenting or embolisation) is anticipated. CT with contrast is usually
done as a first choice investigation, because the broadest spectrum of
information can be obtained.
Endoscopy
Endoscopy may show oesophageal injury.
The sensitivity of either rigid or flexible endoscopy depends on the skill and
experience of the endoscopist.
Gastrografin swallow
The Gastrografin swallow is not sensitive for Zone III injuries, but is
sensitive for lower injuries, in combination with endoscopy if required.
Bronchoscopy/ laryngoscopy
Laryngoscopy may be used diagnostically and therapeutically: blood clots
may be removed.
Bronchoscopy may be indicated in selected cases to diagnose airway
injuries, remove foreign material, or lavage the aireays.
31.
32. Management
Consider early intubaiton or surgical airway.
If all the investigations are normal, the
patient may be observed over-night and
discharged home if there is no deterioration.
A haemothorax should be managed
accordingly.
If the patient is bleeding, or the airway is
compromised, or the investigations are
abnormal, immediate surgical management is
required.
Small pharyngeal and tracheal injuries can be
treated conservatively.
34. Pitfalls
Always adhere to ABCDE for the initial management of
the patient.
Always frequently reassess the airway in order to
recognise airway problems that may develop over
time.
Do a thorough assessment of platysmal penetration.
The wound should never be probed as bleeding is
sure to be precipitated.
Penetrating neck injuries may involve the lung or
mediastinal structures. The chest should always be
assessed.
Vascular injuries may cause neurological
manifestations.