Neck trauma

NECK

1. NECK AND LARYNGEAL TRAUMA DR PRIYANKA

2. Complex network of neurovasuclar & muscular structures supported by various fascial planes. In the neck multiple vital structures are vulnerable to injury in a small anatomic area and not protected by bone.

3. Neck Injuries Neck trauma mechanisms: blunt penetrating : 5-10% of all trauma cases The types of injuries: airway ( laryngotracheal ), digestive tract ( pharyngoesophageal ), vascular system neurologic system

4. PENETRATING INJURIES Stab injuries –Knife, razor blades, glass, etc •Predictable damage pathway •Stab vs. Projectile Injury •Higher incidence of subclavian laceration •Lower incidence of spinal cord injury •Projectile •Handgun •Rifle •Shotgun

5. Three basic types: low velocity (handguns), high velocity (rifles) and shotguns. Handguns ~ 400ft/lb, Rifles 3000ft/lb, Shotgun energy and impact varies with distance

6. Projectile injury mechanics Kinetic Injury of Missile: more energy = more damage •Velocity: higher velocity = more KE, •Yaw –“tumbling”, deflection of the bullet around the axis of the travel. •More tumble = more transmitted energy, larger damage path •Strong metal jacket allows through and through injury

7. HANDGUNS - Classified by projectile type, speed and calibre. Tumbling bullet : deflection of the bullet around the axis of the travel, causes more injury in a wider path Low velocity bullets(lead shielded) leave a radiographic pathway

8. RIFLE Hunting rifle- soft tip bullets create larger cavity, no exit wound, fragments causing injury far away from primary path. Military rifle- bullets create clean hole, through and through wound without lead track to follow High velocity missiles tears tissues & transmits energy to surrounding tissue. Cavity upto 30 times size of missile created & pulsate 5-10ms creating waves of contraction and expansion of tissues. Hence the finding of punctured viscus without direct penetration- alerts the surgeon to examine trachea and esophagus even when bullet is 2 inches away.

9. Bullet Tip •“Expanding bullet” – hollowpoint , softnose •More energy transmission and more soft tissue injury •Entry/Exit wound, pathway through tissue

10. ZONES IN NECK

11. Roon & Christensen`s Classification Zone 1: superiorly from the sternal notch & clavicles to the cricoid cartilage (injury affects both neck & mediastinal structures) Zone 2: cricoid cartilage to the angle of the mandible Zone 3: angle of the mandible to the

12. ZONES OF NECK - CONTENTS Zone I: includes the vertebral and proximal carotid arteries, major thoracic vessels, superior mediastinum , lungs, esophagus, trachea, thoracic duct, spinal cord

13. Zone II: involve the carotid and vertebral arteries, jugular veins, esophagus, trachea, larynx, and spinal cord Zone III: includes the distal carotid and vertebral arteries, pharynx, and spinal cord

14. ZONE I considerations Dangerous Area, Mortality –12% •Close proximity of vasculature to thorax •Osseous Shield : bony thorax and clavicle •Protects against injury •Surgical Access difficult •Surgical Access •May require sternotomy or thoracotomy •Mandatory exploration is NOT recommended

15. ZONE II considerations Largest and most commonly involved area ~60-75% •No Osseous Shield •Surgical Access “Easy” •Proximal and Distal control of vasculature “easy” • Fascial layers may tamponade •Elective vs Mandatory Exploration

16. ZONE III considerations Dangerous Area •Proximity of vasculature to skull base, high carotid injury Cranial nerve injury at skull base •Surgical Access difficult •Surgical Access • Mandibulotomy •Craniotomy •Mandatory exploration is NOT recommended •Cranial neuropathies may be indicative of injury to nearby vasculature •Frequent examination oral cavity

17. FASCIAL PLANES Platysma : thin muscle covers the entire anterior triangle and the anteroinferior aspect of the posterior triangle; serves as an important planar landmark when evaluating penetrating neck injuries Deep cervical fascia: invest deep structures; important due to the pretracheal deep fascia’s communication to the anterior mediastinum (neck trauma can lead to mediastinitis )

18. SIGNS AND SYMPTOMS AIRWAY : .Respiratory distress • Stridor •Hoarseness • Hemoptysis •Tracheal Deviation •Subcutaneous Emphysema •Sucking Wound

19. VASCULAR: •Hematoma •Persistent Bleeding •Absent Carotid Pulse •Bruit •Thrill • Hypovolemic Shock •Change of Sensorium •Neurologic Deficit

20. NEUROLOGIC • Hemiplegia •Quadriplegia •Coma •Cranial Nerve Deficit •Change of Sensorium •Hoarseness •*Signs of stroke/cerebral ischemia

21. ESOPHAGEAL INJURIES •Subcutaneous Emphysema • Dysphagia • Odynophagia • Hematemesis • Hemoptysis •Tachycardia •Fever •Most commonly missed zone II injury • Significant Delayedmorbidity and mortality

22. Hard Signs Ongoing hemorrhage Large or expanding hematoma Bruit Massive blood loss at scene Hemiparesis or hemiplegia Extensive subcutaneous emphysema Stridor

23. INITIAL MANAGEMENT ABC’s Always be ready for Intubation, C ricothyroidotomy , T racheostomy ( multible intubation attempts might enlarge a pyriform sinus laceration/ tracheal tear may be exacerated by neck extensions) Extension of neck should be avoided until a cervical spine injury is ruled out Direct pressure for bleeding

24. AP and Lateral neck and chest x-rays( chest tube insertion in pneumothorax ) Look for vascular injury(pulse deficit,active bleeding,hypotension , expanding hematoma) in high volume trauma Acute spinal injury- hypotension without tachycardia Look for Cranial Nerve injury, in cases with 12th nerve injury suspect carotid artery injury Horners Syndrome- injury to sympathetic chain or carotid atery

25. DIAGNOSTIC EVALUATION .Angiography •Carotid Ultrasound •CT Angiography •MRI/MRA •Direct laryngoscopy , rigid bronchoscopy , rigid esophagoscopy •Flexible endoscopy • Gastrograffin /Barium swallow

26. CT ANGIOGRAPHY Advantages •Superior image quality •Readily available, quick •Limited interuservariability •Safe •Shows surrounding structures Limitations Poor timing of contrast load Patient movement Metallic artifact Not therapeutic

27. Angiography In zone I and zone III : routinely When b/l neck involved, 4 vessel angiography : b/l carotid and vertebral arteries Zone II injuries : easily accesible , low risk for exploration Angiography : stable pts with persistent hemorrhage / neurologic deficits

28. MANAGEMENT Zone 1 dangerous area- vascular strusture close to neck, osseous shield makes surgical exploration difficult. Right side approached through median sternotomy , left side by left anterior thoracotomy . High fatality rate.

29. Zone 2 –common 60-75% Mandatory or selective exploration depending on signs, symptoms, haemodynamic stability, diagnostic radiographic , endoscopic techniques, angiography Zone 3- protected by skeletal structures and difficult to explore. May need to displace or divide mandible. Injury to cranial nerves exiting skull base indicate injuries To great vessels in their proximity(may necessitate craniotomy for exploration)

30. MANDATORY VS SELECTIVE MANAGEMENT Mandatory immediate surgical exploration Massive bleeding, expanding hematoma, non expanding hematoma with haemodynamic instability, haemomediastinum , hemothorax , hypovolemic shock Selective exploration Hemodynamically stable, non life threatening injuries, Can undergo imaging investigations.

31. SELECTIVE VS MANADATORY NECK EXPLORATION

32. Exploration of Neck general principles GA Airway- nasotracheal / orotracheal intubation; cricothyroidotomy / traecheotomy Position- supine, neck extended, turned to opposite side(if no C spine injury) Exposure-chest & face for zone 1 & 3 injuries Approach- localised injury :horizontal skin crease insicion , subplatysmal flaps; wider exploration: lond incision along anterior border of sternocleidomastoid . Additional exposure:zone 1 divide omohyoid muscle, for bilateral exploration :apron flap; zone 3 –anterior dislocation of mandible.

33. Active bleeding should be controlled with digital pressure until direct vascular control is achieved Wounds should not be probed, cannulated or locally explored these can dislodge clot and lead to uncontrolled hemorrhage or embolism

34. Zone I - SCM incision + sternotomy Zone II - SCM incision Zone III - post-auricular extension with SCM incision + mandibular subluxation Operative Approach

35. Provides exposure of the carotid sheath, pharynx and cervical esophagus Can be lengthened to provide more extensive proximal or distal exposure If bilateral exploration is necessary, separate incisions can be done SCM Incision

36. Neck trauma damages cervical vessels in 25% of cases Penetrating trauma predominates 30% have associated injuries in the neck and thorax Blunt trauma accounts for < 10% of injuries mortality rate = 10 – 30% Cervical Vascular Injuries

37. VASCULAR PENETRATION Zone I : Thoracic surgery low cervical incision : sufficient exposure Zone II : Injuries at skull base may require mandibulotomy for exposure ICA injury : fogarty catheter through PruitT Inahara shunt All veins can be safely ligated , if both ijv ‘s injured : one side repaired.

38. Common carotid/ ICA in zone II : exploration is mandatory If the artery is not pulsating : external carotid branches may be followed retrograde from facial artery at submandibular / superiro thyroid artery Vascular injuries : end to end anastomosis autovenous grafting ligation for irreparable injuries

39. Injuries to the ICA are more problematic Simple injuries with no interruption of flow should be repaired Injuries to CCA or ICA with interrupted flow in the vessel, repair creates a theoretical disadvantage Management

40. Interruption of flow may lead to focal brain ischemia and partial disruption of blood-brain barrier Sudden restoration of blood flow may cause hemorrhage in the area of ischemia and worsen the extent of brain injury Converted an ischemic infarct into a hemorrhagic infarct Disadvantage