Airway Anaesthesia
for Final FRCA
Written Final FRCA Teaching
July 2016
Common questions
Airway emergencies:
• Bleeding tonsil
• Inhaled foreign body
• Croup/epiglottitis
Topical airway stuff:
• Tracheostomy/DAS guidelines
• NAP 4
• BJA Education
ENT:
• Laser airway surgery
• Jet ventilation
• Airway imaging
Maxfacs:
• Intraoral abscesses
• Facial fractures
Equipment:
• Supraglottic airways
• Fibreoptic scope
Quick quiz
Anatomy, nerve supply and
anaesthesia
Discuss intubation options

17 year old female with fractured
mandible requiring ORIF. MO
1cm. Very anxious. Requesting
EMLA for cannulation.

27 year old male with facial
swelling due to intra-oral
abscess requiring I &D in
theatre. MO 1cm.

54 year old male for
microlaryngoscopy for biopsy of
laryngeal lesion. Normal MO.
Previous surgery abandoned
due to failed direct laryngoscopy.
PMH radiotherapy for tonsillar
cancer.
Facial fractures
Intra-oral abscesses
 Maxillary infection
 Wisdom teeth
Airway Management Considerations
Superficial
Reduced nasal patency
Trismus related to pain unless spread
to other spaces
Masticator
Severe trismus
Rupture on manipulation
Floor of mouth
Trismus
Raised floor of mouth (can’t protrude
tongue)
Reduced oro-pharyngeal space
Potential rupture on airway
manipulation
Dysphagia, drooling
Supraglottitis-oedema of laryngeal
structures
Difficult tracheal access
Pharyngeal
Neck stiffness
Reduced oro-pharyngeal space
Rupture
Dysphagia, drooling
Airway distortion/oedema and
stridor
Distant spread (mediastinitis)
Implications of radiotherapy
Site of cancer
Pathology
Problems
Implications
Face & Buccal mucosa
Necrosis
Mucositis
Oral thrush
Orofacial pain
Ulceration
Fistula formation
Difficult mask ventilation
Mucosal bleeding
TMJ
Fibrosis
Trismus
Difficult laryngoscopy
Tongue
Fibrosis
Inflammation
Glossitis
Glossomegaly
Reduced tongue mobility
Difficult laryngoscopy
Dentition
Increased risk caries
Loose teeth
Dental loss
Difficulty mask ventilation
Risk of dental trauma
Floor of mouth
Fibrosis
Reduced mobility
Difficult laryngoscopy
Mandible
Osteonecrosis
Micrognathia
Mandibular recession
Difficult mask ventilation
Difficult laryngoscopyreduction in mandibular
space
Suprahyoid region
Fibrosis
Oedema
Firm/woody neck tissue
Skin tethering
Difficult laryngoscopylimited atlanto-axial
flexion/extension
Lower airway
Epiglottic & glottic
oedema
Snoring
Hoarseness
Cough
Difficult laryngoscopy
Difficult endotracheal
intubation
SAQ One
A 71-year-old patient requires a rigid bronchoscopy for biopsy
and possible resection of an endobronchial tumour.
a) What are the possible indications for rigid bronchoscopy
under GA?
b) What are the options for anaesthesia and ventilation during
bronchoscopy?
c) What are the possible complications of rigid bronchoscopy?
d) What are the indications for bronchoscopy on the intensive
care unit?
Indications for rigid bronchoscopy
Diagnostic
Therapeutic
Massive haemoptysis
Massive haemoptysis
Biopsy tumour
Stent insertion
Tracheal dilation
Removal inhaled FB
Tumour debulking
Options for anaesthesia/ventilation?
• Apnoeic oxygenation
• Spontaneous assisted ventilation
• Controlled ventilation
• Manual jet ventilation
• High frequency jet ventilation
Jet ventilation
• Low frequency vs high frequency
• Jet stream from high pressure source
generates tidal volume
• Passive expiration from lung and chest
wall recoil (NB HFOV)
Manual jet ventilation




Indications
Physiological principle?
Gas exchange by bulk flow
How to use?
High frequency jet ventilation
Small Vt (1-3 ml/kg) from a high pressure jet at
supra-physiological frequencies 1-10Hz
• Gas exchange: pendelluft/
laminar flow/longitudinal dispersion
• Facilitate surgical access
• Lower mean airway pressure
(useful if gas leak)
Complications
Bronchoscopy related
Anaesthesia related
Airway bleeding
Hypoxaemia
Trauma to vocal cords
Hypercarbia
Laryngospasm
Barotrauma/Pneumothorax
Aspiration
Surgical emphysema
Bronchospasm
Awareness?
Oedema-post op stridor
Gastric distension
Bronchoscopy in ICU
Inspection
Sampling
Therapy
Aspiration
x
x
x
Infection
x
x
x
Lobar
collapse/atelect
asis
x
x
x
Airway
management
x
x
Airway
assessment
x
x
Foreign Body
x
x
Strictures/steno
sis
x
x
Haemoptysis/h
aemorrhage
x
x
SAQ Two
A 54 year old patient with base of tongue cancer
presents for a hemiglossectomy and radial forearm
free flap reconstruction
a) What conditions/procedures require the formation
of a free flap? (2 marks)
b) Which specific factors must the anaesthetist
consider when assessing this patient prior to surgery
(10 marks)
c) List the benefits of a free flap reconstruction (2
marks)
d) What are the causes of flap failure and how may
they be prevented in the perioperative period? (6
marks)
Free Flap Surgery
Conditions requiring free flap
Reconstructive surgery head and
neck cancers
Breast reconstructive surgery
Reconstructive hand surgery
Burns
Trauma
Donor Sites in H&N
Intra-oral defects
• Radial forearm
• Anterolateral thigh
Mandibular reconstruction
• Fibula
• Iliac crest (DCIA)
• Scapula
Pre-operative assessment
Patient:
Smoking
Alcohol
Pre-op BP
Nutrition
Anaesthetic:
Airway-previous radiotherapy, site of lesion
Side of flap (venous/arterial access)
Surgical:
Duration
Positioning
Temperature
DVT prophylaxis
Tracheostomy formation
Benefits of free flap
① Integrity
② Function
③ Aesthetics
• Benefits of taking tissue from a distant site
• Better outcomes if future radiotherapy
needed
• Minimal donor site morbidity
Causes of flap failure
•
Primary ischaemia
• Reperfusion injury
• Secondary ischaemia
Free flap physiology
• Intact arterial and venous system
• Denervated
• No lymphatic drainage
Physiological principles?
• Hagen-Pouiselle
• Laplace
Flap Failure
Arterial occlusion
 Flat
 Pale
 Cool
 Decreased or absent
CRT
 No bleeding on
pinprick
 Loss of arterial
Doppler signal
Venous occlusion
• Oedematous
• Congested (pinkpurple)
• CRT brisk
• Dark bleeding on
pinprick
• Loss of venous
Doppler signal
SBA
You are called to see a patient with tracheostomy .
His saturation dropped from 98% to 86% on 50%
oxygen. What will be your next immediate step?
a.
b.
c.
d.
e.
Call for help
Connect the tracheostomy tube to a circuit
and do manual bagging
Give 100% oxygen
Pass suction catheter through tracheostomy
tube
Remove tracheostomy tube
SBA
70 year old male undergoes radical neck dissection for
malignancy. Patient becomes unstable when tumour is
being dissected from carotid sheath. SBP drops to 60,
HR 110, SpO2 87% and ETCO2 1.9kpa. The most likely
is:
a.
b.
c.
d.
e.
Anaphylaxis
Carotid sinus manipulation
Myocardial ischaemia
Tension pneumothorax
Venous air embolism
SBA
Following a difficult intubation but easy bag and mask
ventilation in an obese lady you cannot hand
ventilate. What will you do first?
a.
b.
c.
d.
e.
Take out ETT
Look at capnograph trace
Look at oxygen saturation
Give nebuliser
Give muscle relaxant
SBA
You are called to see a patient in recovery one hour
following a thyroidectomy operation. He has difficulty
breathing and his O2 saturation has dropped to 89%
from 97% despite a FiO2 of 60%. The front of his neck
appears swollen despite no blood in the suction drain.
What will be your next line of action:
a.
b.
c.
d.
e.
Get the surgeons to re-explore the wound
Open the clips in the front of the neck
Give CPAP using NIV
Nebulised Adrenaline
Urgent USS
MCQ
Complication of percutaneous tracheostomy
are:
a.
Tracheal stenosis
b.
Surgical emphysema
c.
Endobronchial intubation
d.
Hypothyroidism
e.
Trachea-oesophageal fistula
MCQ
With regards to high frequency ventilation:
a. I:E ratio 1:3 is used
b. It is used in management of broncho-
pleural fistula
c. Increases FRC
d. Requires continuous infusion of muscle
relaxants
e. Reduces the risk of barotrauma
What we’ve covered:
Anatomy and nerve supply of the upper
airways
Relevance of intra-oral abscesses & facial #
Implications of head and neck radiotherapy
Bronchoscopy/principles of jet ventilation
Free flap surgery
References
Pathak et al. Ventilation and anaesthetic approaches for rigid
bronchoscopy. Annals American Thoracic Society. 2014, 4:
628-634.
Conclon, C. High frequency jet ventilation. Anaesthesia
Tutorial of the Week 271. 2012.
Evans et al. Jet Ventilation. CEACCP. 2007, 7: 2-5.
Darshane et al. Responsive contingency planning: a novel
system for anticipated difficulty in airway management. BJA
2007, 99(6): 898-905.
Adams J and Charlton P. Anaesthesia for microvascular free
tissue transfer. BJA CEPD 2003,3:33-37.
Nimalan N. Anaesthesia for free flap breast reconstruction.
BJA Education. 2015.
Kabadayi. S Bronchoscpy in critical care. BJA Education 2016.