THE DIFFICULT AIRWAY
MANAGEMENT IN ADULT
CRITICAL CARE
5 MAY 2014
J MATSHE
AIRWAY MANAGEMENT
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Obligatory & Necessary skill for ALLL Critical care
practitioners
FAILURE to maintain airway & provide adequate
oxygenation=↑ patient morbidity & mortality;
psychologically-distressing to attending registrar
ALL Critical Care patients-Initially viewed to have a
potentially difficult airway & REMEMBER have less
physiological reserves VS airway intervention @
elective surgery
DEFINITION
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DIFFICULT AIRWAY: Acc to ASA guidelines
2013=Clinical situation whereby conventionally
trained anaesthetist experiences DIFFICULTY
with either:
MASK VENTILATION or
TRACHEAL INTUBATION or
BOTH ( “CAN’T INTUBATE, CAN’T
VENTILATE”) NB: AVOID AVOID AVOID!!!!!!!
DIFFICULT MASK VENTILATION
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Unassited anaesthetist cannot maintain arterial
oxygen saturation ≥90% by mask ventilation using
100% Oxygen & positive pressure OR
Cannot reverse signs of inadequate ventilation eg.
Absence of chest movement & exhaled CO2 OR
Presence of cyanosis
DIFFICULT LARYNGOSCOPY

Difficulty visualising any portion of vocal cords
using a conventional laryngoscope: Cormack
Lehane 3(epiglottis only)/4(soft palate only)
DIFFICULT ENDO-TRACHEAL
INTUBATION
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› 3 Attempts @ inserting ET tube Or
› 10 minutes to perform using conventional
equipment
OUTLINE
INDICATIONS FOR INTUBATION
 AIRWAY ASSESSMENT & PREDICTING DIFFICULT
AIRWAY:
 PRE-INTUBATION STRATEGY
-Preparation
-Pre-Oxygenation
-Positioning
-Premedication
 PLANS & BACK UP PLANS
 ADJUNCTS
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INDICATIONS FOR INTUBATION
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Inadequate Oxygenation
Inadequate Ventilation
Anticipate development of inadequate
oxygenation/ventilation
Airway protection
PREDISPOSING FACTORS TO
DIFFICULT INTUBATION
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OPERATOR related: Unassisted junior trainee
after-hours with no senior/specialist assistance
DISEASE related: All intubations EMERGENCIES
PATIENT related: EMERGENCY=Shortened
preparation time;Recent previous intubationpredispose airway edema, subgottic inflammation &
even stenosis & Operator Stress due to patient’s
deteriorating condition
AIRWAY ASSESSMENT
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History for airway assessment
Potential Problems
Anaesthesia records
All stages
Previous intubation trauma
All stages
Previous surgery, radio-therapy to head/neck
All stages
Airway disease process
All stages
Systemic disease(rheum arthr, ankylos spondyl) Diff laryngoscopy
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Sleep apnoea
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Previous tracheostomy
Difficult laryngoscopy and intubation
Gastro-oesophageal reflux
Full stomach
Aspiration of gastric contents
Aspiration of gastric contents
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Loss of airway tone & Difficult laryngoscopy
AIRWAY ASSESSMENT
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Exam for A A
Potential Problems
Stridor
All stages
Obesity
Loss of airway tone and difficult laryngoscopy
Short neck
Difficult laryngoscopy
↓ mouth opening Difficult laryngoscopy
Receding jaw
Difficult laryngoscopy
Hamster mouth
Difficult laryngoscopy
Buck teeth
Difficult laryngoscopy
Missing upper teeth Difficult laryngoscopy
Respiratory difficulty Difficult laryngoscopy
Neck masses
All stages
Position of larynx/ trachea and availability of cricothryroid membrane
Difficult laryngoscopy and intubation
BAG MASK VENTILATION
BAG MASK VENTILATION
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INTEGRAL component of Airway mx
If done correctly & successfully: Gives time to
prepare for definitive airway mx
Entails 3 Principles: Patent Airway, Good
mask seal & Proper ventilation
IDENTIFYING DIFFICULT BMV
M
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O
A
N
S
Mask seal: Can’t approximate
mask
Obesity:Redundant tissues
impede airflow
Age ›55yrs: Loss of tissue
elasticity
No teeth:Mask doesn’t sit
properly
Stiff lungs/body:↑pressure
needed
OPENING AIRWAY MANOUVERE 1
HEAD TILT CHIN LIFT:
1ST HAND DOWNWARD PRESSURE TOFOREHEAD ; 2ND HAND INDEX &
MIDDLE FINGERS LIFT CHIN
OPENING AIRWAY MANOUVRE 2
JAW THRUST-UNSTABLE CERVICAL SPINE:
PLACE HEELS OF HANDS ON PARIETO-OCCIPAL AREA & GRASP ANGLES
OF MANDIBLE WITH FINGERS & DISPLACE JAW ANTERIORLY
OPENING AIRWAY ADJUNCT 1
OROPHARYNGEAL: GUEDEL-SIZE CORRECTLY; INSERT-CURVE
INVERTED, ROTATE 180˚ AS TIP REACHES POSTERIOR PHARYNX
AVOID IN AWAKE PATIENT
OPENING AIRWAY ADJUNCT 2
NASOPHARYNGEAL AIRWAY
MASK VENTILATION TECHNIQUE 1
1 HAND: ALIGN PATIENT’S EXTERNAL AUDITORY MEATUS WITH
STERNAL NOTCH USING E-C METHOD FOR MASK SEAL & BAG WITH
OTHER HAND
MASK VENTILATION TECHNIQUE 2
2 HANDED: 1 PERSON HOLDS MASK WITH BOTH HANDS USING E-C
METHOD OR APPLY PRESSURE WITH THUMBS & LIFT JAW WITH FINGERS;
2ND PERSON BAGS
ENDOTRACHEAL INTUBATION
THE DIFFICULT INTUBATION
Failure to intubate can result in severe adverse
events such as:
 Airway trauma
 Aspiration
 Hypoxemia/Anoxic brain injury
 Hypotension
 Cardiac arrest & Death
BE PREPARED & HAVE A PLAN
IDENTIFYING THE DIFFICULT
INTUBATION
L
E
M
O
 LOOK
 EVALUATE 3-3-2
 MALLAMPATI
 OBSTRUCTION/OBESITY
 NECK MOBILITY
N
DIFFICULT INTUBATION
ASSESSMENT
“LOOK”
 Externally: Facial
trauma;
Unusual/Distorted
anatomy
 Internally: Foreign
body; Secretions;
Obstructing mass
DIFFICULT INTUBATION ASSESSMENT
EVALUATE: 3-3-2 RULE
Mouth opening
Tip of mentum to hyoid bone Thyromental distance
Access to airway
and obtaining glottic
view
Can tongue be deflected
to accomdate
laryngoscope
Predicts location larynx to
base of the tongue. If larynx high
angles difficult
DIFFICULT INTUBATION
ASSESSMENT
DIFFICULT AIRWAY ASSESSMENT
OBESITY
 Redundant tissues in
upper airway may
obscure glottis
 Positioning imp:
Pillows under
shoulders
OBSTBUCTION
 Epiglottitis, Quisy
DIFFICULT AIRWAY ASSESSMENT
NECK MOBILITY
↓ Cervical spine
mobility: RA,DM,
Cervical immobility
→COMPROMISED
Sniffing position
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PRE-INTUBATION STRATEGY
PREPARATION
PRE-OXYGENATION
POSITIONING
PREMEDICATION
PREPARATION
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ASSESS AIRWAY: Look for signs of possible
difficult bag mask ventilation/intubation OR both
ASSEMBLE EQUIPMENT: Check functional
status
PREPARE MEDICATION
DEVELOP AIRWAY MANAGEMENT PLAN
WITH BACK UP PLANS
PREPARATION
S
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T
O
P
Suction
Tools(Laryngoscope)
Oxygen
Position/Plan
M
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A
I
D
Monitors(Bp,Sats,Cap)
Ambu-bag,Airw devic
Iv access
Drugs
INFLUENCE OF LARYNGOSCOPES
Macintosh
-No difference
compared to Miller
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LARYNGOSCOPES
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Miller
LARYNGOSCOPES
McCoy
-Has an angulated tip
-Improves visualisation
with less force; in
neutral position
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LARYNGOSCOPES
Bullard/Airtraq
-Rigid fibre-optic
laryngoscope
-Alignment of axes not
required
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PREOXYGENATION
Establish oxygen reservoir
-Replace nitrogenous room air mixture with 100%
oxygen
 Challenge in ICU
-Head of bed elevation
-NIPPV
 Challenge in Obesity & Critically ill patients
-Desaturate much quicker
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POSITIONING
SUPINE
-Access to airway
obstructed
 SNIFFING
-Head elevated, Neck
extended
-Imaginary horizontal line
from external auditory
meatus to sternal notch
-Access to airway
improved
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PREMEDICATION
ICU pts-require very little or no drugs
L
O
A
D
Lidocaine: Reactive airways & ↑ICP
Opioids: Blunt sympathetic response & ↑BP
Atropine: Bradycardia in kids particularly
Defasciculating agent-↓dose competitive
neuromuscular blockade: ↑ICP
INDUCTION AGENTS
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KETAMINE: Sedation & Analgesia; No
hypotension; Bronchodilatory effect; Respiratory
drive preserved; ↑ICP & BP. Dose: 1-2mg/kg iv
PROPOFOL: Rapid onset; No analgesia;
Hypotension. Dose: 1.5-3mg/kg iv
MIDAZOLAM: Time to effect › 15min ;
Hypotension. Dose: 0.1-0.3mg/kg iv
ETOMIDATE: Rapid onset; No
analgesia/Hypotension. Dose: 0.3mg/kg
MUSCLE RELAXANTS
SUXAMETHONIUM
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Onset 45-60sec; DOA
6-10min.
Dose: 1-1.5mg/kg iv;
C/I-Rhabdomyolysis,
Hyperkalemia, Burns ›
72hrs & Hx Malignant
HT
ROCURONIUM
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Onset 60min; Longer
DOA than Sux.
Dose 0.8 - 1.2mg/kg iv
LARYNGOSCOPY TECHNIQUE
BIMANUAL LARYNGOSCOPY
CRICOID PRESSURE
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Avoid regurgitation of
gastric contents by
occluding upper end
of oesophagus
May worsen glottic
view
BURP: Improve
glottic view by
manipulating thyroid
cartilage
LARYNGOSCOPY
INSERTING ET TUBE
CONFIRM ET TUBE PLACEMENT
AIRWAY ADJUNCTS
BOUGIE
VIDEO LARYNGOSCOPE
LMA
CRICOTHYROID CANNULA
SURGICAL CRICOTHYROIDOTOMY KIT
BOUGIE
VIDEO LARYNGOSCOPY
VIDEO LARYNGOSCOPES
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GLIDESCOPE
VIDEO LARYNGOSCOPES
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C-MAC
LMAs
CLASSIC LMA
INTUBATING LMA/FASTRACK
NEEDLE CRICOTHYROIDOTOMY
SURGICAL
CRICOTHYROIDOTOMY
THE PLAN
AND BACK UP PLANS.....
REFERENCES
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Critical care medicine.2008;36(7):2163-2173
Anaesthesiology.2013;118:Practice guidelines for
manangement of the difficult airway
Critical care and resuscitation.2003;5:43-52
Endotracheal intubation in ICU by Dr D Oxman
2013