Laryngeal Trauma
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Transcript of Laryngeal Trauma
Laryngeal Trauma
Dr Chris Acott
Dr Russell M Davies 1914 - 1991
BMJ July 24 1880 pp 123
“He sat in bed supporting himself with stiffened arms: his head was thrown forwards, and he had the distressed anxiety so characteristic of impending suffocation …. His inspirations were crowing and laboured, and there was a very frequent forced attempt to swallow, attended by extreme pain, … He spoke in a muffled whisper, and confined his answers, when possible, to monosyllables, or substituted signs by head or hand. …”
Sir William MacEwen 1848-1924
Laryngeal trauma
Blunt Penetrating
Laryngeal Trauma: incidence
• Rare – 1/5000 – 1/137,000
» Current Opinion Otolaryngology 2000; 8(6):497-502
– 1/14,000 – 1/42,000» American Association Oral Maxillofacial
Surgeons 2006: 203-214
Laryngeal Trauma: incidence
• Rare – Why? – under reported - paucity of peer reviewed
data - » American Association Oral Maxillofacial
Surgeons 2006: 203-214» Current Opinion Otolaryngology 2000
8(6):497-502
– patients die before reaching hospital – not reported in data
– larynx well protected & flexible• mandible - superiorly; sternocleidomastoids –
laterally; clavicles – inferiorly. » American Association Oral Maxillofacial
Surgeons 2006: 203-214» Current Opinion Otolaryngology 2000
8(6):497-502
Laryngeal Trauma: Diagnosis
• DIAGNOSIS OF SUSPICION – laryngeal trauma NEEDS to be excluded– diagnosis may not be obvious in a patient with
an uncompromised airway– symptoms & signs unrelated to degree of trauma
• this may also be reason for under reporting
• Once diagnosed the extent of injury must be defined before any attempt at intubation– ETT across injured larynx can convert mucosal
laceration to a more complex problem• ETT can cause complete laryngo-tracheal separation
Laryngeal Trauma: Morbidity/mortality
• Mortality– 0-18%
» J Trauma 1990 30(1):87-93
• Delay in diagnosis increases morbidity & mortality– pharyngeal, oesophageal & vessel injury must
be excluded
• Concurrent occult oesophageal injury significantly contributes to morbidity & mortality– evaluation of oesophagus mandatory - NB
before placement N/G tube
Laryngeal trauma:Diagnosis of Suspicion
• HISTORY• Hoarseness - 90%• Tenderness - 90%• Subcutaneous
emphysema - 60%• Anterior neck
contusion - 40%• SOB - 40%
Current Opinion Otolaryngology 2000 8(6):497-502
Laryngeal trauma:Diagnosis of Suspicion
• Inability supine - 30%• Pain - 30%• Tracheal deviation -
20%• Haemoptypsis - 20%• Dysphagia - 10%• Aphonia - 10%
Current Opinion Otolaryngology 2000 8(6):497-502
Associated injuries
• Chest trauma - 40%• Facial #s - 30%• Facial laceration - 30%• Long Bone #s - 30%• Oesophageal laceration - 10%• Head injury - 10%• Pharyngeal trauma/perforation - rare• None - 30%
Current Opinion Otolaryngology 2000 8(6):497-502
Laryngeal trauma:History may give some idea of
injury• Complete L-T separation associated with:
– hyperextension injuries: avulsion of larynx – tearing of fibrous ring between CC & 1st tracheal ring
– strangulation– rarely associated with blunt trauma– ASSOCIATED WITH # CRICOID CARTILAGE
• # Thyroid Cartilage:– neck hyperflexion
• Knife or Gunshot wounds – evaluate the oesophagus
Multiple threats to airway:
• Direct penetration• Distorted tissue
planes• Haematoma• Oedema• Excessive blood &
secretions
Multiple threats to airway: ..2
• IPPV & coughing:– worsen air leaks– s/c emphysema
• Cricoid pressure: – lead to laryngo-
tracheal separation
Multiple threats to airway: ..3
• Cricothyroidotomy: – may compound
injury
• ETT: – mucosal disruption– false passage– laryngo-tracheal
separation
Laryngeal trauma:Airway
Stable Unstable
Airway can become unstable
at anytime
Laryngeal trauma:Airway
Stable Unstable
Inability to tolerate supine position –
URGENT TRACHEOSTOMY
Laryngeal Injuries: ..1
• Vocal cord injury• Arytenoid swelling &
dislocation• Crico-tracheal
separation– usually associated with
death
• Soft tissue contusion• Superficial mucosal
laceration
Laryngeal Injuries: …2
• Thyroid cartilage fracture– most common site
of fracture
• Epiglottic fracture• Mixed injuries• Shattered calcified
thyroid cartilage in elderly
Investigations:
• Plain Xray (may not be helpful due to extensive s/c emphysema)– pneumomediastinum &
pneumothorax– air in tissues– # Cx spine
• CT– cartilage & soft tissue
injury– airway patency
Investigations: .2
• Laryngoscopy– vocal cord paralysis– mucosal & cartilage
separation– haematoma– Laceration– Arytenoid displacement
Fractured Larynx:Management
• Tracheostomy under LA vs GA• Management is NOT A LEARNING
EXPERIENCE• HELIOX • FOB & Cricothyroidotomy may not
be appropriate• Intubation may not be appropriate
– may cause complete separation
WHY HELIOX?
1. Less dense – work of breathing less.
2. Decrease amount of subcutaneous emphysema
Helium - Upper airway obstruction
“When it is available an even better effect can be expected from inhalation of 79% Helium with 21% Oxygen”– Wylie Churchill Davidson 1960 pp 382
Reynold’s Number
• < 2000 laminar flow• 2000 -10000 transitional flow• >10000 turbulent flow
Turbulent flow
• Turbulent flow– F ~ P1/2/Lρ1/2
F = flow; P = pressure; ρ = density; L = length.
(Radius important but not expressible as a power of the diameter - as radius decreases
flow decreases also)
Turbulent flow: flow greater with Heliox than air or O2
Density important
Relationship between pressure and flow during turbulent flow
• Even if flow is turbulent there is less work of breathing and greater flow with given pressure change Comparison between Heliox (black)
& air or O2 (yellow)
Heliox
O2
Why Helium?Hylegaard et al
• O2 breathing initial bubble growth– O2 > He solubility in fat
– build up O2 around bubble in tissue
• Helium breathing bubble constantly shrunk
Helium mixtures: Physics /Gas flux
• GAS FLUX = diffusion x solubility coefficient– He>N2 diffusibility (smaller atomic wt)
– He<N2 solubility in fatty tissue, water & blood
– He<O2 solubility in fatty tissue
• therefore:- – N2 or O2 flux into fatty tissue > He flux
HENSE ANY AIR POCKETS WILL SHRINK.
WHY HELIOX?
• HELIOX WILL GAIN PATIENT’S CONFIDENCE AND MAKE BREATHING EASIER
• AND MAY DECREASE THE AMOUNT OF S/C EMPHYSEMA.
Heliox on Anaesthetic Machine
5 Case Histories
Maybe others – but not recognised.• trauma patients on ICU ventilator – laryngeal
oedema when extubated a couple of days later – ‘floppy epiglottis’ on intubation
1. Walker in mountains– hoarse voice in GP’s surgery– GA - laryngoscopy – unable to identify any
structures, unable to intubate (fortunately!!)– obstructed during tracheostomy with retractors
2. Motorcyclist on farmer’s property– intubated at scene
5 Case Histories
3. MVA – car rolled.– hanged by seat belt upside down– complete tracheal/laryngeal separation– partial obstruction with palpation of neck - GA
4. Motorcyclist – MVA – Modbury Hospital– gaseous induction– complete obstruction during tracheostomy –
retractors again
5. And ….
…. patient number 5.
• Able to speak and say “EEEE”
• Air bubbling freely from thyroid holes– covered with wet drape
• CT scan –no # Cricoid!!– found to have one
• No s/c emphysema• No respiratory distress• Able to lie flat
TRACHEOSTOMY
Head extended exposing the neck.
Neck palpated. LA injected.
Horizontal 6 cm incision to anterior borders sternocleidomastoid muscles.
Skin, subcut tissue, platysma to deep fascia.
May not be able to extend the head.Palpation of structures may
press on trachea & cause anxiety.
LA stings – may increase anxiety.
Veins may be enlarged due to inspiratory/expiratory pressures
SURGICAL TRACHEOSTOMY
Self retaining retractor placed,dissection to strap muscles
Strap muscles divided & retracted. Langerbech retractors placed.
Retractor placement important – to much pressure
can obstruct airway.
Thyroid isthmus exposed, clamped , divided and ligated, rotated externally & sutured.
Trachea is exposed
Retractor placement again important – to much pressure
can obstruct airway.
Tracheal incision sited over
2nd & 3rd or 3rd & 4th tracheal rings.
Tracheostomy tube inserted
Placement of tube may cause some distress
Summary:
• Rare – diagnosis of suspicion• Mortality ~20%
– increases if unrecognised
• Concurrent oesophageal injury increases morbidity & mortality– needs to be excluded
• Inability to lie supine – indication immediate tracheostomy
Summary: ..2
• Consider Heliox if available• Avoid coughing – may make s/c
emphysema worse and airway impossible
• Awake tracheostomy vs SV GA?– careful palpation– care with retractors
3rd SIG Airway MeetingLorne March 9-11 2012
“Everything airways including problems outside the OT”
Thank You
Laryngeal Trauma
Dr Chris Acott
Head extended exposing the neck.**
Neck palpated. LA injected.*
Horizontal 6 cm incision.Anterior borders sternocleidomastoid muscles.
Skin, subcut tissue, platysma to deep fascia.
Self retaining retractor placed, dissection to strap muscles.*
Strap muscles divided & retracted.
Langerbech retractors placed.**
Thyroid Isthmus divided.
Trachea is exposed
Sited over 2nd & 3rd or 3rd & 4th tracheal rings